HomeMy WebLinkAboutHaines-Skagway Region Feasibility Study Volume 2 - Appendices 1982HAINES-SKAGWAY REGION
FEASIBILITY STUDY
Volume II -Appendices
R. W BECK AND AsSOCIATES, INC
ENGINEERS AND CONSULTANTS
April 1982
L...---__ ALASIiA 1-•• \VElt AU1.'HOltITY __ ~
VOLUME I -REPORT
SUMMARY
GENERAL OUTLINE OF REPORT
PART A -SELECTION OF GENERATION PLAN
PART B -FEASIBILITY INVESTIGATIONS OF WEST CREEK HYDROELECTRIC PROJECT
PART C -COMMENTS FROM REVIEWING AGENCIES
PART D -SUMMARY OF GENERATION ALTERNATIVES
VOLUME II -APPENDICES
APPENDIX A -PHASE II -FEASIBILITY STUDY INTERIM REPORT
APPENDIX B -GEOTECHNICAL INVESTIGATION
APPENDIX C -ENVIRONMENTAL INVESTIGATIONS
APPENDIX A
PHASE II -FEASIBILITY STUDY INTERIM REPORT
m. BOX 1400
;ITI(A, ALASKA
)9B35
'ILENO.
R. W BECK ANO AsSOCIATES, INC
HH-1559-HG3-AA
3110
Mr. Robert A. Mohn
Director of Engineering
Alaska Power Authority
334 West 5th Avenue
Anchorage, Alaska 99501
Dear Robert:
Subject:
INTRODUCTION
ENGINEERS AND CONSULTANTS
TOWER BUILDING
7TH AVENUE AT OLIVE WAY
SEATILE, WASHINGTON 98101
106-611-5000
Haines-Skagway Region Project
Phase II -Feasibility Study
Interim Report
OCT 1 11982
ALASKA PO\"'-~-;\UTH::!TY
~O. BOX 6616
KETCHIKAN, ALASKA
99901
October 14, 1q81
This letter report updates the April 1981 Addendum to the Recon-
naissance Report on Alternatives for the Haines-Skagway Region (Addendum).
The Addendum concluded that a West Creek storage project serving both communi-
ties was the preferred alternative for meeting the energy needs of the two
communittes. However, there remained a possibHity that the Goat Lake site
might be more economical because at the time the Addendum was prepared, no
site reconnaissance had been conducted of the Goat Lake stte and thus the
resulting estimates of costs and power output were not of a level comparable
to the other sites. To make a comparable evaluation between the West Cree~
and Goat Lake sttes, the Authority authorized a site reconnatssance of the
Goat Lake site, a reevaluation of potential power output and an update of the
cost estimates of the most economical alternatives identified in the Adden-
dum. This work was aimed at determining whether or not the West Creek stte
was in fact the preferred alternative for meeting the energy needs of Hatnes
and Skagway. This letter report presents the results of the studies and our
recommendations based on these studies.
The four alternatives considered were: (1) West Creek with a stor-
age reservoir; (2) Goat Lake with capacity to meet the requirements of both
communities; (3) a non-intertie alternative with Upper Chtlkoot for Haines and
a West Creek diversion project for Skagway; and (4) a non-intertie alternative
Mr. Robert A. Mohn -2-October 14, 1q81
with Upper Chilkoot for Haines and Goat Lake for Skagl-'ay. These appear in
Table 8 of the Addendum. In general the methodologies and assumptions dis-
cussed in the Addendum were used in this update. The major changes occur in a
revision to the Goat Lake Project design concept based on the site reconnais-
sance and an updating of the cost estimates. Revisions to the West Creek
Project layout and cost estimate were also made based on preliminary evalua-
tion of the data currently being gathered. Revised Project Data and Prelimi-
nary Cost Estimates are shown in Tables 1 and 2, respectively.
GOAT LAKE
The Goat Lake site was visited on July 27, 1981 bv senior personnel
of R. W. Beck and Associates, Inc., Converse Ward Davis Dixon, Inc., and
Environaid. '1'he lake was sounded using a lead weight on a 100-foot Jine to
evaluate existing storage. Possible dam sites at the north end of the lake
and at the southwest outlet were inspected. On July 29, 1981 the proposed
powerhouse location near Pitchfork Falls was inspected.
Goat Lake is a small perched lake located at EJ 2915~ east and
south of the Skagway River about seven miles northeast of Skagway. The lake
lies in a geologic lineament which is part of a linear feature extending from
the East Fork of the Skagway River for about 20 miles. This linear feature
runs basically parallel to the Taiya River and the Lynn Canal which are con-
sidered part of a more extensive geologic lineament and fault system. The
lake is fed by a glacier at its south end and a small stream entering from the
east. The glacier covers about 40% of the 4.24-square-mile drainage area con-
tributing runoff to the lake. The glacier terminates near the south end of
the lake in a coarse rubble moraine, consisting of principally large angular
granitic blocks. On the east side of the lake the topography climbs steeply
to peaks of El 5700-6000. On the west side, the lake is bounded by a granitic
ridge extending basically north-south along the axis of the lake. '1'his ridge
is highest toward the north and drops close to or slightly below lake level at
the southern end where the actual elevation of the rock ridge is masked by the
overlying glacial moraine.
The lake has a small visible outlet through a fourto f1ve-foot-wide
notch in the ridge near the south end. Water flows through a small, shallow
pool before spilling down the mountain via Pitchfork Falls to the Skagway
River. The terminal moraine of the glacier extends over the southern edge of
the lake and also down to this pool. At the time of the site reconnaissance,
flow was entering the shallow pool through the moraine, indicating that the
granitic ridge may drop below lake level or that part of the hasin ~unoff may
bypass the lake and run off directly through the moraine. At the time of the
reconnaissance, approximately one-third of the flow in Pitchfork Falls came
through the notch and two-thirds came through the moraine. Based on the field
observations, it was not possi ble to determine whether the f1 ow through the
moraine originates from the glacier, from the lake, or both. Lacking docu-
mented information, it is only possible to speculate as to the source of the
flow from the moraine below the lake outlet and the effect it would have on
flows available for development of a hydro project.
Mr. Robert A. Mohn -3-October 14, 1981
At the north end of the lake there is a 50-foot-wide notch filled
with large granitic blocks and smaller rubble which is estimated to be 20 to
30 feet deep. There is evidence that water flows through this notch at times,
but there was only a small amount of seepage at the time of the reconnaissance.
Soundings taken in the lake showed that the lake is very deep, gen-
erally greater than 100 feet throughout and in excess of 270 feet in the cen-
ter, the limit of the measuring equipment available during reconnaissance.
From Goat Lake the ridge slopes steeply to the Skagway River be-
low. In the upper part the surface is mostly exposed rock with some over-
burden and trees. At about El 1000 the railroad passes along the slope
through a series of rock cuts, fills and bridges. In the section below the
railroad the slope continues steeply to the river. The slope in that section
contains more tree cover, but with some vertical cliffs. The inspection re-
vealed no flat areas of sufficient size for the powerhouse site. In general
the rock exposures appeared competent and suitable for tunneling and general
construction.
Because of the depth of the lake, it was concluded that a project
with storage could be developed without a dam to raise the lake level. The
preliminary conceptual layout includes a Jake tap 60 feet below the existing
lake at El 2855, a 600-foot-long horizontal tunnel, an inclined shaft extend-
ing to a lower near-horizontal tunnel ending at a powerhouse near the Skagway
River. The powerhouse would be built underground because of the steep ter-
rain. Access to the powerhouse would be by road and bridge from the State
Highway across the river. Access to the lake and the upper end of the shaft
would be by helicopter or tramway.
A construction cost estimate was made based on this conceptuaJ lay-
out at July 1981 price levels. Contingencies for the Goat Lake Project were
assumed to be 25% of the Direct Construction Cost. Engineering and Owner Ad-
ministration were estimated to be 15% of the sum of the Direct Construction
Cost and Contingencies. The cost estimates are summarized in Table 2.
Using the same methodology as in the Addendum, average annual in-
flow to Goat Lake was estimated using the Region 10 Water Resources Atlas pre-
pared by Ott Water Engineers, with average monthly distribution simBar to
those observed at the three gages in the area. However, observations during
the reconnaissance indicate that not all the inflow will necessarily be usable
for generation since an indeterminate portion of it may be passing directly
through the moraine at the south end of the lake. In order to assess the
potential impact of reduced available inflows, a sensitivity analysis was per-
formed using two assumed inflow reductions. First, 50% of the runoff was
assumed to be available for generation with the remaining 50% dischargjng
through the moraine. This results in a project which could meet 65% of the
1996 projected annual energy requirements in Haines and Skagway. The second
assumption was that 75% of the flow would be available for generation, with
25% discharging through the moraine. With 75% of the flow, the 1996 annual
energy requirements would just be met by the estimated average annual flow.
Mr. Robert A. Mohn -4-Octoher 14, 1q81
In both cases it should be noted that these estimates are based on estimated
average annual flows without adjustment for the annual variatton which would
be expected. Thus, the actual available energy during any year will depend on
the flows during that year plus carryover storage from previous years.
The hydrology of Goat Lake is an extremely complex problem involv-
ing an ungaged small high elevation lake with a diversion of flow of unknown
size masked by a glacial moraine. The problem is further complicated by the
fact that no gage records exist for similar high elevation basins in the
area. The three stream gages in the Haines-Skagway Region represent consider-
ably larger drainage areas at much lower elevations. Elsewhere in Southeast
Alaska gages on small, high elevation basins have only recently been in-
stalled. Until long-term records are developed, these provide essent5ally no
opportunity for correlations.
In order to reliably evaluate the hydrology at Goat Lake, it would
be necessary to install two gages on the outlet and a single gage on the in-
flowing stream from the east. The two gages at the outlet, one at the notch
outlet of the lake and one at the outlet of the pond, would provide a break-
down as to amount of flow through the notch vs. the amount through the
moraine. The gage on the inflowing stream will provide data on the runoff
from the non-glacial area in the event that the investigations show that none
of the glacial melt enters the lake. A precipitation gage should also be in-
stalled for correlation with gages at tidewater. After several years of rec-
ord, these would allow a more reliable evaluation of the flow entering the
lake, the flow which discharges through the notch and the flow which passes
through the moraine. The validity of this short-term record for estimating
long-term trends and annual variations will depend on the degree of correla-
tion between the Goat Lake record and other records in the region.
Thus, at best the current estimates of hydrolo~y and power output
of Goat Lake must be recognized as being very suspect and potentially unreli-
able. This certainly makes the comparisons with West. Creek, for which good
gaging records do exist, less meaningful.
WEST CREEK
The preliminary layout and construction cost estimate were revised
based on the new topography and site visits made in late July 1981. The proj-
ect concept remained the same with a storage dam with its foundation located
at about the 600-foot contour, a tunnel and shaft combination leading to a
powerhouse south of West Creek, and a tailrace channel returning flow t.o West
Creek. Based on improved topography obtained from recent mapping, the volume
of embankment has increased. rhe powerhouse has been moved further south and
the tailrace channel lengthened to move the downstream end of the tunnel away
from an al1uvial slope and into bedrock. The cost estimate was modifi ed to
include these changes. The cost estimate includes a contingency of 20% which
reflects the availability of higher quality data for West Creek than that cur-
rently available for Goat Lake.
Mr. Robert A. Mohn -5-October 14, 1q81
The hydrology of West Creek was evaluated on a monthly basis using
the 16 years of gaging records. The results of the hydrologic analysis show
that there is sufficient annual flow to meet the 1996 energy requirements and
that the original estimates of storage requirements were conservative.
Further refinements of these estimates will be made to determine the appropri-
ate reservoir sizing and will be included jn the Feasibility Report.
NON-INTERTIE ALTERNATIVES
Both non-intertie alternatives included a project at Upper rhilkoot
Lake which would meet about 75% of the 1996 energy requirements for Haines.
This site was again inspected on July 28, 1981, but no changes in the concep-
tual layout were made. It was noted, however, that a substantial delta ex-
isted in the lake at the mouth of the small stream entering the lake from the
east. This had not been noted previously and it could mean that a project at
the site would experience a problem with sedimentation, but further study
would be necessary before definitive statements can be made. The cost esti-
mates were revised to reflect July 1981 costs.
The non-intertie alternatives included two possible projects for
Skagway, a run-of-river project on West Creek and a storage project at Goat
Lake. The run-of-river project on West Creek is the same as that included in
the Addendum. The cost estimate was updated based on the field studies com-
pleted to date and adjusted to a July 1981 price level. The conceptual layout
of the Goat Lake Project was modified to be similar to the project for Haines
and Skagway, but with a smaller installed capacity suitable to meet only the
requirements of Skagway. The 1996 energy requirements of Skagway would prob-
ably be completely met by this project since even with a 50% reduction in in-
flow there should he sufficient flow to meet the requirements. ~he cost esti-
mate was revised to be consistent with the new layout and at a July 1981 cost
level.
ECONOMIC ANALYSIS
In the same manner as in the Addendum, these four alternatives were
economically evaluated using a present-worth, benefit-cost analysis over a
period starting in 1981 and extending 50 years. Benefits were taken as the
present worth of continued use of diesel generation over the entire analysis
period. Capital and operation and maintenance costs were assumed at a July
1981 base and not escalated. Fossil-fuel costs were escalated at 2.6% per
year through the first 20 years and then held constant. Project costs were
taken as the total cost of meeting annual requirements using a combination of
the hydro project and diesel generation. ~he same escalation assumptions were
applied to costs as to benefits. All costs were discounted at 3% to a present
worth value and summed to give the total cost.
Mr. Robert A. Mohn -6-October 14, 1q81
Table 3 summarizes the results of the economic analysis. For the
Goat Lake alternative, meeting Haines and Skagway requirements, two costs are
given, one for the assumed 50% reduction in flow and one for the assumed 25%
reduction in flow. The revised economic analysis shows that all four alterna-
tives are more economical over a 50-year life than continued use of diesel
generation. The analysis also shows that the West Creek stora~e project is
the most economical alternative except when compared with the Goat Lake Proj-
ect with the assumed 25% reduction in flow, a comparison which as noted previ-
ously must be questioned.
CONCLUSIONS
These studies confirm the conclusions presented in the Addendum -
that development of the West Creek site with storage to meet the needs of both
Haines and Skagway will best provide for the long-term energy needs of the
region. The Goat Lake site appears attractive only if sufficient flow is
available to meet the power needs of both communities. At this Ume there is
not enough information available on Goat Lake or a similar drainage area to
permit a reliable estimate of the quantity of water which might be available.
A data gathering program of at least three years duration would be required
before any realistic determination could be made. This program would not
guarantee that the Goat Lake site would yield sufficient water, but only pro-
vide the basis for a decision regarding future investigation. Conversely, at
the West Creek site sufficient hydrologic base data are available to a~sure a
reliable supply of water is available; also, geotechnical investigations have
proceeded to a stage where it is likely that no insurmountable foundation
problems will be encountered; and environmental investigations have concluded
that the environmental impacts are minor.
Delay in the development of a project will certainly result in a
more expensive project because of inflation. Construction cost increases on
water resources projects has been running at more than 10% per year for the
past several years. Thus, if the recommended hydrologic investigation pro~ram
were implemented at Goat Lake, the Goat Lake Project cost compared with West
Creek would be greater by about 33% than that indicated in Table 2. Further,
if the hydrologic investigations concluded that there is not adequate water
available, or if other investigations revealed unforeseen foundation or con-
struction problems at Goat Lake, Haines and Skagway might be forced back to
development of West Creek, but at a higher cost due to inflation.
Thus, it is our recommendation that the investigations on West
Creek continue with the intention of preparing an FERC License Application as
originally planned. The Goat Lake site should be considered for future devel-
opment when energy and load requirements necessitate another hydro project.
Very truly yours,
R. W. BECK AND ASSOCIATES, INC.
~o,~
Project Manager
TABLE 1
HAINES-SKAGWAY REGION STUDY
INTERIM REPORT
PROJECT DATA
West Creek(l) West Creek(2) Goat Lake (3)
Installed Capacity (kW) ..... . 5,350
Static Head (ft.) ...........• 670
Drainage Area (sq. mi.) ..... . 37.2
Mean Annual Flow (cfs) ......• 288
Dam Height (ft.) 107
Power Tunnel Length (ft.) .... 10,500
Power Shaft Length (ft.) 870
(1) -With 107-foot-high storage dam.
1,500
595
37.2
288
20
14,300
(Pipeline)
5,350
2,150
4.2
28
3,600
2,500
(2) -With diversion dam and pipeline, Skagway energy requirements only.
(3) -Haines and Skagway energy requirements.
(4) -Skagway energy requirements only.
(5) -With 40-foot-high storage dam, Haines energy requirements only.
Goat Lake (4) Upper Chilkoot(5)
2,100 3,600
2,150 2,110
4.2 5
28 32
40
3,600 3,150
2,500 2,450
Preparatory Work .............
Access Roads .................
Darn and Reservoir and Spillway
Power Conduit and Intake .....
Power Plant ..................
Transmission Lines ...........
Total Direct Construction Cost
(July 1981 Level)
Contingenc ies (6) ............
Engineering and Administration
(15 %) ......................
Total Construction Cost ......
(July 1981 Level)
TABLE 2
HAINES-SKAGWAY REGION STUDY
PHASE II INTERIM REPORT
SUMMARY OF PRELIMINARY COST ESTIMATES
West Creek west Creek Goat Lake
( 1) ( 2) ( 3)
$ 1,558,000 $ 550,000 $ 995,000
657,000 642,000 850,000
12,167,000 985,000
10,815,000 3,473,000 11, 358,000
2,461,000 2,195,000 4,275,000
12,292,000 1, 29 3, 000 11,500,000
39,950,000 9,138,000 28,978,000
7,990,000 1,828,000 7,245,000
7,191,000 1, 645, 000 5,433,000
$55,131,000 $12,611,000 $41,656,000
(1) -With 107-foot-high storage dam.
(2) -With diversion dam and pipeline, Skagway energy requirements only.
(3) -Haines and Skagway energy requirements.
(4) -Skagway energy requirements.
(5) -With 40-foot-high storage dam, Haines energy requirements only.
(6) -Contingencies were 20% for West Creek, 25% for Goat Lake and
Upper Chilkoot.
Goat Lake Upper Ch ilkoot
( 4) ( 5)
$ 995,000 $ 696,000
850,000 1,070,000
11,631,000
11,358,000 4,766,000
4,275,000 1, 552, 000
1,712,000 5,361,000
19,190,000 25,076,000
4,798,000 6,269,000
3,598,000 4,702,000
$27,586,000 $36,047,000
TABLE 3
HAINES-SKAGWAY REGION STUDY
PHASE II INTERIM REPORT
SUMMARY OF ECONOMIC ANALYSIS
Present Worth Cost
Al ternati ve Haines Skagway
Base Case $128,957,900 $52,960,000
West Creek (1) (Haines and Skagway)
Goat Lake (2) (Haines and Skagway)
Goat Lake (5) (Skagway) and
Upper Chilkoot(6) (Haines)
West Creek (7) (Skagway) and
Upper Chilkoot (6) (Haines) ...... .
(1) -With 107-foot-high storage darn.
(2) -With 5, 350-kW installed capacity.
(3) -With 50% reduction in inflow.
(4) -With 25% reduction in inflow.
( 5) -With 2,100-kW installed capacity.
(6) -With 40-foot-high storage darn.
(7) -with diversion darn and pipeline.
107,012,000 49,642,000
107,012,000 42,059,000
Combined
$181,917,900
132,422,000
152,559,000
117,899,000
156,654,000
149,071,000
Benef it-Cost
Ratio
1.37
1.19(3)
1.54(4)
1.16
1.22
L,./~SECT IONS 9,10 , II, +5 ANOis ... T;·2.~ 5; R.60E
ExistinCjj PLAN
Existing ground surface
Railroad EI.IOOO±
Powerhouse
_-L-_ '----...,;:.....I::....;.;m.;.;;;od~I;.;.;·fi~ed::..:..:.H.:.;:.S;;..;. t..:,u:..;:nn..;.;:e;.;..1 .::L;...=..:3:.,::O:.,::O:.,::O;.,.' __ ---.:&l T. W. EI. 765 ±
PROF1LE ALONG ct. OF POWER CONDUIT
NOTE
Where rock cover on power conduit is
less than i head, power conduit is to be
concrete lined and where less than i
head, it is to be steel and concrete lined.
1000' 0
I I I I I I I " I I
1000'
I
R. W. BECK and ASSOCIATES
'"""EElS AND CONAIlTANn
S.1m.. Wllhinlton
ALASKA POWER AUTHORITY
ANCHORAGE 1 ALASKA
HAINES -SKAGWAY REGION STUDY
GOAT LAKE HYDROELECTRIC PROJECT
CONCEPTUAL ARRANGEMENT
DATI:
MAR. 1981 .... 12
APPENDIX B
GEOTECHNICAL INVESTIGATION
Converse Consultants
GeotttehnlC41I Engineering
and Applied SClencel
GEOTECHNICAL INVESTIGATION
HAINES-SKAGWAY REGION/FEASIBILITY STUDY
WEST CREEK PROJECT
ALASKA POWER AUTHORITY
ANCHORAGE, ALASKA
Prepared for:
R. W. Beck and Associates
200 Tower Building
Seattle, Wsahington 98101
Converse Project No. 81-5165
July 1982
Converse Conlultanta. Inc.
300 Elliott Avenue West
SUite 150
Seattle. Washington 98119
Telephone 206 285-5200
July 6, 1982
R. W. Beck and Associates
200 Tower Building
Seventh Avenue at Olive Way
Seattle, Washington 98101
Converse Consultants
Geotechnical Englneertng
and Applied Science.
81-5165-01
Attention: Mr. Donald R. Melnick, Partner
Gentl emen:
Pursuant to our agreement dated August 12, 1981, herewith is trans-
mitted our report entitled "Geotechnical Investigation, Haines-Skagway
Region/Feasibility Study, West Creek Project".
The purpose of this investigation was to produce, compile and interpret
geological, geophysical and geotechnical data to be used in detailed
feasibility studies of the proposed West Creek Project.
Mr. William S. Bliton, Principal Engineering Geologist served as pro-
ject geologist for our studies. He was assisted by numerous profes-
sionals in our firm including: Or. Ronald E. Bucknam, Managing Vice
President, Mr. Dean E. Ryden, Principal Engineer; Mr. David A. Yone-
mitsu and Mr. Carl E. Benson, Staff Engineeri ng Geologists. The in-
vestigation was performed under the overall supervision of the under-
signed.
We believe the level of effort applied to this geotechnical investiga-
tion was adequate for this feasibility phase of study. Analysis of
data from this investigation indicates that the West Creek Project is
geotechnically feasible.
The assistance and support received from personnel of R. W. Beck and
Associates, Inc. during this investigation was invaluable. We appreci-
ate the opportunity to serve as your geotechnical consultant on this
project.
Very truly yours,
CONVERSE CONSULTANTS, INC.
titan ~. tJ'lJd?
;el-~
Alan L. OINeill
Vice President
WSB/ALO/dmh
Conyerwe Conaultantl. Inc.
300 Elliott Avenue West
SUite 150
Seattle. Washington 98119
Telephone 206 285·5200
TABLE OF CONTENTS
1. EXECUTIVE SUMMARY
2. I NTRODUCTI ON
2.1 Purpose of Investigation
2.2 Authorization
2.3 Project Description
2.4 Scope of Work
2.5 Field Investigation
2.5.1 Geologic Mapping
2.5.2 Drilling
2.5.3 Seismic Refraction
2.6 Laboratory Testing
2.6.1 Construction Materials
2.6.2 Rock Testing
2.7 Limitations
3. REGIONAL GEOLOGIC SETTING
3.1 Regional Geology
4. FAULTING AND SEISMICITY
4.1 Regional Faults
4.1.1 Queen Charlotte Fault
4.1.2 Fairweather Fault
4.1.3 Denali Fault System
4.1.4 Chatham Strait-Lynn Canal Fault
4.1.5 Chinakof-Baranof Fault
4.1.6 Peril Strait Fault
4.1.7 Other Faults
4.2 Regional Lineaments
4.2.1 Coast Range Megalineament
4.2.2 Glacier Bay Lineament
Converse Consultants, Inc.
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Table of Contents (continued)
4.3 Regional Seismicity
4.4 Project Faults and Lineaments
5. PROJECT GEOLOGY
5.1 Bedrock
5.2 Overburden
5.2.1 Glacial Drift
5.2.2 Terrace Deposits
5.2.3 Glacial Moraines
5.2.4 A 11 uv i urn
5.2.5 Talus Deposits
5.3 Dam Site
5.3.1 Geology
5.4 Spillway
5.4·.1 Left Abutment Spillway
5.4.2 Right Abutment Spillway
5.5 West Creek Diversion
5.5.1 Geo 1 ogy
5.6 Power Tunnel
5.6.1 Geology -Alternatives 1 through 3
5.6.2 Geology -Alernative 4
5.7 Intake
5.7.1 Geology
5.8 Surge Tank
5.8.1 Geology
5.9 Powerhouse
5.9.1 Powerhouse Alternative 1
5.9.2 Powerhouse Alternatives 2-1 and 2-2
5.9.3 Powerhouse Alternative 3
5.10 Reservoir
5.10.1 Geology
Converse Consultants, Inc.
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Table of Contents (continued)
Page No.
6. ENGINEERING CONSIDERATIONS 48
6.1 Dam Foundation 48
6.1.1 Bedrock Propert i es 48
6.1. 2 Foundation Excavation 51
6.1. 3 Foundation Treatment 52
6.1. 4 Foundation Drainage 53
6.2 Spillway 53
6.2.1 Foundation Exca vat ion 54
6.3 Diversion 54
6.3.1 Channel Diversion 54
6.3.2 Cofferdams 55
6.3.3 Diversion Tunnel 55
6.4 Power Tunnel 56
6.4.1 Excavation Characteri st i cs 57
6.4.2 Excavation Stab-j 1 i zation and Support 58
6.4.3 Lining 60
6.4.4 Surface Penstock 60
6.5 Intake 60
6.5.1 Foundation Excavation 61
6.6 Su rge Shaft 61
6.6.1 Excavation Characteri stics 62
6.7 Powerhouse 62
6.7.1 Foundations Excavation 62
6.8 Reservoir 63
6.9 Construction Materials 64
6.9.1 Concrete Aggregate 64
6.9.2 Embankment Materi al s 65
6.10 Seismic Desi gn 66
BIBLIOGRAPHY 67
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Table of contents (continued)
TABLES
4-1 Modified Mercalli Intensity Scale of 1931
6-1 Rock Test Summary
6-2 Summary of Rock Test Data
FIGURES
5-1 Explanation of Upper Hemisphere Polar Joint
5-2 Joi nt Rosette -Dam Site
5-3 Joint Rosette -Power Tunnel Alternative
5-4 Joint Rosette -Powerhouse Alternatives
DRAWINGS
1. Project Location Map
2. Regional Geology
3. P roj ect Geology
4. Project Lineaments
5. Dam Site Geology
6. Dam Site Cross Section
7. Powerhouse Geology
8. Reservoir Geology
9. Reservoir Geology
10. Earthquake Epicenter and Fault Map
APPENDIX A -Drilling Equipment and Procedures
APPENDIX B -Borrow Exploration
APPENDIX C -Rock Testing
APPENDIX D -Construction Materials Testing
APPENDIX E -Seismic Refraction Survey
Plot
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50
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1. EXECUTIVE SUMMARY
The proposed Haines-Skagway Regional Study-West Creek Project is located
in southeastern Alaska approximately seven m"iles northwest of Skagway,
Alaska. The project will consist of a 120-to 150-foot high embankment
dam with a concrete face, or a roller-compacted concrete (gravity) dam.
This phase II study was for the purpose of providing preliminary geo-
technical data for use in detailed feasibility design studies. The
exploratory work included: 12 borings with an aggregate footage of
1,647.3 feet; 5,740 lineal feet of seismic refraction profiling; geo-
logic mapping of the project area; in-situ water testing in eight bor-
ings; bulk sampling of potential borrow sources; laboratory testing of
rock and borrow materials; and a review of available data regarding
seismicity of the area.
Analysis of data from these investigations indicates that the West Creek
Project is feasible from a geotechnical viewpoint.
DAM SITE
o The dam foundations will consist of sound granodiorite.
o Recommended foundation excavation to reach sound rock consists of the
removal of all overburden materials beneath the dam and the upper 5 to
8 feet of bedrock in the toe slab area. For the roller-compacted con-
crete dam, recommended foundation excavation consists of the removal
of all overburden and upper 5 to 8 feet of bedrock beneath the dam.
o Overburden on the proposed abutments is relatively thin, ranging from
zero to approximately 10 feet and averaging approximately 8 feet in
thi cknes s.
o Alluvial deposits in the creek channel are estimated on the order of
20 feet in thickness.
o A highly fractured and/or altered bedrock zone may be present beneath
the creek channel.
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o A single-line grout curtain along with consolidation grouting is rec-
ommended, especially for the roller-compacted concrete dam.
DIVERSION
o Diversion of West Creek can be accomplished by constructing a coffer-
dam and a diversion tunnel, or by diverting water at low flow along
the channel and placing a conduit in the river channel bed over which
the dam will be constructed.
o Geotechnically, it is feasible to construct a diversion tunnel beneath
either abutment, topography and geologic conditions may result in bet-
ter portal conditions and more rock cover over the tunnel in the right
abutment.
SPILLWAY
o A spillway can be excavated across either abutment.
o The major portion of either spillway excavation will be in bedrock.
Excavated slopes in bedrock can be planned at l/3H:IV (horizontal to
vertical ).
POWER TUNNEL
o The tunnel will be driven almost entirely in good quality granodio-
rite; one of the powerhouse alternatives would require a short tunnel
through sand, gravel and boulders.
o Power tunnel alternat; ve 1 will have a downstream portal at approxi-
mately el evat; on 600 feet and w"ill be connected to the powerhouse by a
surface penstock.
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o The power tunnel will cross at least one fault zone and numerous line-
aments anticipated to be zones of highly fractured and/or sheared
rock.
o It is judged the tunnel can be dri ven either by convent ional methods
or by tunnel boring machine.
o It is judged that approximately 50 percent of the tunnel will require
rock stabilization if driven by conventional methods and approximately
25 percent if driven by tunnel boring machine.
SURGE SHAFT
o The surge shaft excavation will be completed in bedrock.
o Several highly fractured, sheared and/or weathered zones will be en-
countered and will require rock stabilization if driven by convention-
al methods. A raised bore may require little or no stabilization.
POWERHOUSE
o Bedrock powerhouse sites are available.
o Excavation slopes in bedrock can be planned at Ij3H:IV while temporary
slopes in overburden can be planned at IH:IV and permanent slopes at
1.5H:IV.
o A powerhouse location underlain by alluvium will require pile support
and a section of soft ground tunnel for the power tunnel.
RESERVOIR
o The major portion of the reservoir perimeter is located in bedrock or
talus. There are no indications of potential landslides.
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o Snow avalanches will occur in the reservoir during the winter, but are
not anticipated to be of the size so as to endanger the project.
o The two glaciers which are present in the upper reaches of the drain-
age are retreating and should not represent a danger.
o Some ice falls and small landslides will probably occur in the talus
deposits. They are anticipated to be limited in size and would not
create waves of a magnitude to endanger the facility.
CONSTRUCTION MATERIALS
o Potential sand and gravel borrow for use as fill and concrete aggre-
gate were identified and sampled.
o No sources of impervious borrow were located in the vicinity of the
project.
o Rock produced from bedrock excavat ions is judged suitable for use in
the embankment fill.
SEISMIC DESIGN
o The project is located in a seismically active region and the seismic
design should consider shaking from a major earthquake during the use-
ful life of the project.
o A faul t, consi dered not acti ve, trends. northwest through the project
area and would be encountered in the power tunnel.
o It is recommended that a peak bedrock acceleration of 0.4g be consid-
ered in design.
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2. INTRODUCTION
2.1 PURPOSE OF INVESTIGATION
The purpose of this investigation was to produce, compile and interpret
geological, geophysical and other geotechnical data to be used for de-
tailed feasibility studies of the Haines-Skagway Regional Study, West
Creek Project.
2.2 AUTHORIZATION
Authorization for the geotechnical feasibility study was provided by
letter from R. W. Beck and Associates, Inc. dated August 12, 1981, in
accordance with Converse Ward Davis Dixon, Inc. (presently Converse Con-
sultants, Inc.) proposal dated June 30, 1981.
2.3 PROJECT DESCRIPTION
The proposed West Creek Hydroelectric Project is located on West Creek,
a tri butary to the Taiya Ri ver, approximately seven mil es northwest of
Skagway, Alaska, as shown on Drawing 1. The proposed project includes
a 120-to 150-foot hi gh embankment dam with a concrete face or a con-
crete gravity dam possibly constructed by the roller-compacted concrete
method. The dam would be located at the upstream portion of a bedrock
constriction on West Creek, approximately 2-1/2 miles upstream of the
poi nt where the creek empti es into the Taiya Ri ver. A surface power-
house is proposed approximately two miles downstream of the dam. The
dam and powerhouse wi 11 be connected by a power tunnel. One of the
schemes combines a short downstream surface penstock with a power tun-
nel. A surge shaft is proposed at a point approximately three-quarters
of the distance to the powerhouse.
Access to the project site will be provided by an extension of West
Creek Road whi ch presently termi nates approxi mately one-half mile from
the dam site. Access to proposed powerhouse areas is generally good.
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2.4 SCOPE OF WORK
The scope of work for the detailed geotechnical feasibility study was
determined in consultation with R. W. Beck and Associates, Inc.
The principal objectives of the study included evaluation of:
1. geological, geophysical, boring and field testing data at the
dam site, power tunnel alignments, and powerhouse locations
to determine preliminary foundation conditions;
2. potential construction borrow sources;
3. geologic hazards in the reservoir area; and
4. general seismic conditions which prevail in the project area.
To fulfill the above objectives, the study entailed:
1. planning and scheduling administrative and field programs and
subcontracting for field support services;
2. compilation and field checking of existing geologic data;
3. performing field investigations as follows:
A. genera 1 ;
1) preliminary geologic mapping of the general project
area between the Taiya River and the upper reaches of
West Creek drainage,
2) examination of aerial photographs to determine faults
and lineaments in the project area,
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B. da17l site;
1) preliminary geologic mapping in the vicinity of the
dam site and spillway areas,
2) geophysical surveys in the area of the dam axis and
spillway,
3) drilling and sampling a total of 779.7 lineal feet in
seven bori ngs,
C. power tunnel;
1) preliminary geologic mapping along the general power
tunnel alignment,
D. su rge shaft;
1) preliminary geologic mapping in the vicinity of the
su rge tank,
2) drilling and sampling a total of 502.2 lineal feet in
boring DH 108,
E. powerhouse;
1) geologic mapping in the vicinity of the powerhouse
alternatives,
2) drilling and sampling a total of 365.4 lineal feet in
four borings at two alternative sites,
3) geophysical surveys in the vicinity of the powerhouse
a lte rnat i ves ,
F. rese rvoi r;
1) geologic mapping of the reserovir area from aerial
photographs, reconnaissance level mapping of poten-
tial borrow areas, and field checking of aerial photo
i nterpretat ion.
4. performing a limited laboratory testing program on potential
construction borrow materials and bedrock cores;
5. preparing all field logs, geologic maps, and cross sections
as necessary; reducing field geophysical data;
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6. performing a geologic and engineering analysis and preparing
a report based on the results of this detailed feasibility
report;
7. preparation and presentation of data for project meetings;
8. consultation with the staff of R. W. Beck and Associ ates,
Inc. and finalization of a geotechnical report.
2.5 FIELD INVESTIGATION
The field investigation included surface geologic mapping, stereographic
aerial photograph interpretation, drilling and in-situ water testing,
and seismic refraction surveys and was supplemented by a review of the
existing geologic data.
2.5.1 Geologic Mapping
Geologic mapping consisted of examination and detailed description of
exposures and correlation of this information with boring data and
aerial photograph interpretation. The data was plotted on topographic
base maps and is shown on Drawings 3 through 7.
2.5.2 Drilling
A total of 12 borings consisting of 1,647.3 lineal feet of drilling was
completed during the investigation. Borings were distributed among pro-
ject features as follows:
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Boring No. Feature Depth of Hole, feet
DH 101 Spi 1 h~ay 100.5
DH 102 Left Dam Abutment 99.8
DH 103 Left Darn Abutment 100.9
DH 104 Left Dam Abutment and
Stream Channel 201.5
DH 105 Right Dam Abutment 100.8
DH 106 Right Dam Abutment 75.2
DH 107 Right Dam Abutment 101.0
DH 108 Surge Tank 502.2
DH 109 Powerhouse A lternat i ve No. 2 141.4
DH 110 Powerhouse A lternat i ve No. 2 98.0
DH 111 Powerhouse Alternative No. 1 50.5
DH 112 Powerhouse Alternative No. 1 75.5
The locations of the above borings are shown on Drawings 3, 5 and 7.
Cont i nuous logs of the core as encountered in the bori ngs were recorded
at the time of drilling and are presented on each boring log in Appendix
A. A complete description of the equipment and procedures used for
drilling is given in Appendix A.
Water pressure tests were completed on borings DH 101 through DH 108.
Water pressure test results are presented along with the boring logs in
Appendix A.
2.5.3 Seismic Refraction
A total of 5,750 lineal feet of seismic refraction profiling was com-
pleted in the project area. The profiling was completed along 12 sepa-
rate lines ranging in length between 275 to 625 feet. The purpose of
the seismic profiling was to determine the depth of various velocity
layers, primarily bedrock, and to aid in assessing the quality of rock.
Seismic lines were distributed among the various project features as
follows:
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Line No. Project Feature Length, feet
SL-1 Powerhouse A lte rnat i ve No. 2 625
SL-2 Powe rhouse Alternative No. 2 525
SL-3 Powerhouse A lte rnat i ve No. 2 550
SL-4 Powerhouse A lte rnat i ve No. 1 500
SL-5 Spillway 275
SL-6 Left Dam Abutment 550
SL-7 Right Da~ Abutment and Intake Area 540
SL-8 Left Dam Abutment 530
SL-9 Right Dam Abutment 280
SL-10 Right Dam Abutment 550
SL-ll Powerhouse A lte rnat i ve No. 3 275
SL-12 Powerhouse A lte rnat i ve No. 1 550
The locations of the lines are shown on Drawings 3, 5 and 7 and the
results of the seismic refraction surveys are shown in Appendix E.
2.6 LABORATORY TESTING
2.6.1 Construction Materials
Several potential borrow areas were identified and sampled during this
study. A limited laboratory testing program was completed to determine
the characteristics of the material for potential use as concrete aggre-
gate and embankment materials. The program included numerous physical
tests and petrologic analyses. The results of these tests are presented
in Appendix D.
2.6.2 Rock Testing
Selected rock core specimens were subjected to a series of laboratory
tests to determine their engineering properties. Tests included deter-
mination of dry unit weight, specific gravity, compressive strength,
modulus of elasticity and Poisson's ratio. In addition, petrographic
ana lyses were conducted for i dent ifi cat i on of the rock type. The re-
sults of the rock testing and petrographic analyses are presented in
Appendix C.
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2.7 LIMITATI ONS
The purpose of this study was to provide geotechnical information to be
utilized in determining the feasibility of the project and to aid in
preliminary design and cost estimates relative to the proposed dam, pow-
erhouse and appurtenant structures. The amount of exploration has been
held to a level commensurate with the stage of feasibility design.
The analyses, conclusions and recommendations contained in this report
are based on site conditions as they existed at the time of these inves-
tigations. Further, it is assumed that the explorations provide data
which are representative of subsurface conditions throughout the site,
i.e., the subsurface conditions everywhere are not significantly differ-
ent from those disclosed by the explorations.
The professional services were performed, findings obtained, and recom-
mendat ions prepared in accordance with generally accepted engi neeri ng
and geologic principles and practices. This warranty is in lieu of all
other warranties, either expressed or implied.
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3. REGIONAL GEOLOGIC SETTING
The West Creek Project is located in southeastern Alaska, as shown in
Drawing 1, and lies within the Coast Range Batholith Complex of the
Pacific Coast Range. The topography of this region is characterized by
glacier-covered, high relief mountains (up to 7,500 feet in elevation),
steep-walled glacially-modified valleys and fiords. The present topog-
raphy is a result of the last major orogeny in late Mesozoic to Tertiary
time, with further modifications by continental glaciation during the
Pliestocene Epoch and by present-day alpine glaciation.
The drainages in the Pacific Coast Range generally flow into many of the
steep fiords and inlets, which are characteristic of southeastern Alas-
ka. These drainages are generally short in length, and were formed by
erosion due to glacial ice and flowing water. Glacial meltwater is
the source for most of the streams, which generally carry substantial
amounts of suspended fine-grained sediments and/or rock flour.
The Coast Range Batholith Complex of the Pacific Coast Range lies within
a region which has been geologically active since the Paleozoic Era.
This region is bounded on the west by the Wrangell-Revillagigedo Meta-
morphi c Belt, and on the east by the Intermontane Belt of the Canadian
Cordillera. The Wrangell-Revillagigedo Belt consists primarily of Tri-
assic to Jurassic Age metamorphic rocks while the Intermontane Belt con-
sists primarily of Triassic through Tertiary sedimentary and volcanic
rocks. The general boundary area between the Wrangell-Revillagigedo
Belt and the Coast Range Bathol ith Complex is characterized by several
fault systems and lineaments (Brew and Morrell 1980, Lathram 1964). The
geologic system of this region is related to interaction of plate tec-
tonics involving collision and subduction of oceanic and continental
plates. (Atwater 1970). This tectonic belt has been active since at
least the late Paleozoic and the last major deformation occurred during
the late Mesozoic and Tertiary with some minor activity continuing into
the Quaternary.
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3.1 REGIONAL GEOLOGY
The portion of the Paclfic Coast Range in the Haines-Skagway area has
had a complex history of sedimentation, deformation, igneous intrusion,
glaciation and erosion. The bedrock which underlies the major portion
of the region consists primarily of granitic crystalline intrusive
rocks, ranging in age from Tertiary to Cretaceous, approximately 40
million to 140 million years before present. These intrusive rocks were
emplaced into the Wrangell-Revillagigedo Metamorphic Belt rocks, ranging
from Pal eozoi c to Mezosoi c in age. The rocks of the Wrangell-Revill a-
gigedo Belt were deposited in the Juneau Synclinorium as marine silt-
stone, shal e, graywacke, 1 imestone, and quartz sandstones, interbedded
with volcanic units (Buddington and Chapin 1929). Since deposition this
sequence of rocks has undergone several cycles of tectonic deformation.
This deformation has produced an intermediate to high-grade metamorphic
suite of schist, quartzite, marble and gneiss with a regional northwest
trend (Lemke, Yehle 1972).
During the early Cretaceous through middle Tertiary, these rocks were
intruded by a large multi-stage batholith known as the Coast Range Plu-
tonic Complex comprised chiefly of diorite, quartz monzonite and grano-
di orite (Brew, Morrell 1980). Along the northwest peri phery of thi s
intrusion a ultramafic body was emplaced during the late Cretaceous time
as a layered mass comprised of dunite proxenite, hornblenite and gabbro
(Brew, Morrell 1980).
Tectonic deformation of the regional rocks has produced two distinct
structural trends, northwest-southeast and northeast-southwest. These
structural trends, in the form of joints and/or shear zones, have pro-
duced strong lineaments which are evident as topographic lows on the
ground su rface and in aeri al photographs. Many di kes of mafi c ori gi n
have been intruded into the regional rocks (Barker 1952). Many of these
dikes have been emplaced along the structural trends described above.
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The present topography of most of this region is largely the result of
continental and alpine glaciation during the Pleistocene Epoch, approx-
imately 13,000 years before present. During the last glacial period, an
average of 5,000 feet of glacial ice covered most of this region (Lemke,
Yehle 1972). The weight of the glacier significantly depressed the
land. Upon retreat of the glaciers, many valleys which had been former-
ly occupied by ice were inundated by the sea. Ongoing isostatic rebound
has resulted in the slow emergence of several areas of land in this
region to above the present sea level. This rebound has caused marine
and beach deposits to be elevated well above sea level in coastal areas
of Haines and Skagway (Lemke, Yhele 1972). Hanging valleys, elongated
and deepened lakes, U-shaped valleys, and deeply scoured embayments,
inlets, and passages reflect the effects of regional glaciation. Lo-
cally, small and large alpine glaciers still occupy many of the steep-
walled valleys and higher mountain sides. Landforms, such as lateral
and terminal moraines, are presently being modified and/or formed.
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4. FAULTING AND SEISMICITY
The study of seismicity of any project area must of necessity begin with
a knowledge of geologic forces affecting the entire region. Earthquakes
occur when masses of rock rupture in response to tectonic stresses with-
in the earth. The force devel opi ng these stresses is associ ated with
the slow movement of large, rigid plates of the earth's crust. As these
lithospheric plates collide, diverge, or grind past each other, the
stresses created are relieved by such geologic processes as faulting
with associated earthquakes, mountain building, and/or volcanism.
4.1 REGIONAL FAULTS
The present seismicity of southeast Alaska and northwest British Colum-
bia appears to be largely controlled by the movement of the Pacific
plate as it abuts the North American plate. In southeast Alaska, geo-
logic processes are controlled by the interaction and deformation of
several faults related to and thought possible to be directly connected
with these plate boundary movements. In southern British Columbia and
the Pacific Northwest, the Pacific and North American plates are sepa-
rated by the small independent Juan de Fuca plate system. In this area
the Juan de Fuca plate is being driven southeastward and thrust beneath
the North American plate. In southeast Alaska and northwestern British
Columbia, the Juan de Fuca plate is not present. The Pacific plate is
being driven northwestward, and abuts the North American plate with an
inferred right lateral movement.
Two major fault systems are present along the west coast of Alaska and
British Columbia. One of the systems is the Denali fault system which
is located inland and roughly parallels the coast. It extends from the
northern portion of southeast Alaska northwestward for 1,600 miles. The
eastern portion of the Denali system includes the Lynn Canal-Chatham
Strait fault, Chilkat River fault, and the Shakwak Valley fault. The
other system is the Queen Charl otte-Fai rweather fault system whi ch is
located offshore and extends from near Vancouver Island northward to
the northern portion of southeast Alaska. The Queen Charlotte fault,
offshore of British Columbia and southeast Alaska, and the Fairweather
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fault, in the northern portion of southeast Alaska, are presently
thought to represent the active boundary between the Pacific and North
American Plates. This zone which includes the Queen Charlotte, Chinakof-
Baranof, Sandspit and Fairweather faults is a vertical to steeply dip-
ping group of right lateral strike-slip transform faults. To the north,
adjoined zones are thrust faults: the Transition fault and the Chugach-
St. Alias fault. These thrust faults mark the zone where the Pacific
Plate is subducted beneath the North American plate. The relationship
of these faults relative to the West Creek Project is shown on Drawing
8. The individual faults are discussed below.
4.1.1 Queen Charlotte Fault
The trace of the active Queen Charlotte fault is marked by a narrow but
highly active zone of seismicity as shown on Drawing 8. Fault plane
solutions for events thought to be centered along the trace show almost
pure str-ike-slip motion (Milne and others 1978). However, analysis of
geophysical data near the Queen Charlotte Islands indicates that the
azimuth of the right lateral strike-slip was N26°W whereas topographic
fault expression was N35°W. This would suggest a minor amount of un-
der thrusting is associated with the fault zone, at least in this area
(Milne and others 1978). The total horizontal offset along the fault is
unknown but is thought to be considerable (Yehle 1978). A recent study
on the adjoining Fairweather fault indicates horizontal movement may
have begun as little as 100,000 years ago (Plafker and others 1978). If
the Queen Charlotte and Fairweather faults are continuous, then there
would be a similar age for commencement of right-lateral movement. A
major problem with this assumption is the relatively minor amount of
horizontal offset, only 5 to 6 kilometers, mapped on the Fairweather
fault as opposed to the much greater offset consi dered on the Queen
Charlotte fault.
4.1.2 Fairweather Fault
The Fairweather fault is generally considered a part of a long zone of
roughly adjoined faults including the northern extension of the Queen
Charlotte fault comprising the boundary between the Pacific and North
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American plates (P1afker and others 1975). The onshore trace of the
Fairweather fault is a northwest-trending depression which can be traced
from Icy Point to the upper Seward Glacier. In the vicinity of Lituya
Bay, between Cross Sound and Yakutat Bay, the depression is nearly one
kilometer in width. Early work suggested that the northern end of the
Fairweather fault continued to the northwest, crossing the St. Elias
Mountains to join the Denali fault zone. Subsequent work indicates that
sufficient offset does not exist along the Denali fault to accommodate
offset known to have occurred along the Fairweather (P1afker and others
1978). Instead, it probably merges with the Chugach-St. E1 i as fault
system between Yakutat Bay and Icy Bay. To the south, the Fai rweather
trends offshore southeast of Lituya Bay where it is thought to join the
Queen Charlotte fault zone.
The onshore length of the Fairweather fault is about 125 miles. Along
most of its length it juxtaposes late Mesozoic flysch, melange and Ceno-
zoic plutons to the southwest against the metamorphic and plutonic rock
to the northeast (P1afker and others 1978). The northeast block has
been uplifted more than 3 miles. Movement along the fault may have
started in the middle Eocene (Yehle 1978).
Presently, the Fairweather fault is a transition fault zone with a dip-
slip component. Radiocarbon dating of Holocene features offset by the
fault indicate a minimum average displacement of 4.8 cm/yr to 5.8 cm/yr
for the last millennium, which corresponds well to the world-wide plate
tectonic data for the Pacific-North American plate boundary of 5.4 cm/
yr. At this high rate of movement the Fairweather would have changed
to a right-lateral fault only 100,000 years ago to accommodate the sug-
gested 5.5 km of right lateral offset (Plafker and others 1978).
Although a number of large events have been attributed to the Fairweath-
er fault, the most recent to be studied in detail as to its surficial
effects was the 7.9 magnitude earthquake of July 10, 1958. Displace-
ments of 6.5 meters lateral and one meter dip-slip (6:1-7:1) were meas-
ured near Cri 11 on Lake southeast of L i tuya Bay (P1 afker and others
1978). The closest approach of the Fai rweather fault to the project
location is approximately 95 miles in the vicinity of Lituya Bay.
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4.1.3 Denali Fault System
The Denali Fault System includes the Denali Fault in western and central
Alaska, the Shakwak Fault in the Yukon, the Chilkat Fault in northern-
most southeast Alaska and its southern continuation, the Chatham Strait-
Lynn Canal Fault (Plafker 1982, Dodds 1982). Although mapped as sepa-
rate segments of the Denali fault system, specific information regarding
the Shakwak and Chilkat Rivers faults is sparse.
The Denali fault system is observed as linear topographic depressions
such as fiords and valleys. Movement along the fault is primarily right
lateral strike slip and some of the faulting probably started before the
Miocene and locally into the Holocene (Yehle 1972). In central Alaska,
faulting includes normal, reverse and thrust components (Brew 1966).
The total length of the Denali fault system including the Chatham Strait
and Lynn Canal faults is 1,300 miles (Plafker 1982). The actual Denali
fault is 870 miles in length. Recent displacement along the Denali
fault system is 3 mm/yr compared to 3 cm/yr during the Holocene (Berg
1972). Displacement in Quaternary deposits are observed along the
McKinley strand. Pleistocene deposits show 5 to 7 km displacement.
Holocene deposits show 200 meters di spl acement. Some vert i ca 1 scarps
are 6 to 15 meters high (Berg 1972).
The Chilkat River fault is interpreted as a continuation of a major
strand of the Chatham Strait fault (Brew and others 1966). The fault
underlies and parallels the Chi-Ikat River Valley and continues north-
westward into Canada where it is assumed to connect with the Shakwak
fault and ultimately with the Denali fault. The fault has a strong
topographic expression and juxtaposing terranes with distinctive geo-
logical and structural styles (MacKevett and others 1974). There are
suggestions that the fault dips steeply and the dominant displacement,
at least during the later stages, was vertical. Information relative
to the time and amount of movement along the fault is sparse. It is
thought faulting is Tertiary in age and may be as young as l"1iocene. A
few large earthquake epicenters have been located near the fault; how-
eve r, a hi gh mi crosei smi city has been documented along the fault near
Ha i nes.
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The closest approach of the Denal i fault system to the project area is
approximately 20 miles near Haines where the Chatham Strait-Lynn Canal
fault joins the Chilkat extension of the Denali.
4.1.4 Chatham Strait-Lynn Canal Fault
The Chatham Strait fault is interpreted as a possible continuation of
the Denal i fault system. Trending N7°W, the fault runs approximately
250 mi les up the Chatham Strait and Lynn Canal to the northern border
of southeast Alaska where it jOins other structures which comprise the
Denali fault zone, a 1,300-mile long plate boundary feature. It has
been suggested that at least 123 mi les of displacement has occurred
along the Chatham Strait-Lynn Canal fault, but its age and present
activity are subject to debate. Recent studies indicate that the fault
has been active since Miocene, while older studies have placed a Ter-
tiary or Cretaceous date for the commencement of activity (Yehle 1977,
Twenhofel and Sainsbury 1958). Recent studies suggest that the only
indication of possible Holocene movement is along the southern end of
Chatham Strait west of Coronation Island. At this point, some defor-
mation and faulted sediments were interpreted from seismic profiles
(Rogers 1976). A seismic monitoring system installed in the general
region in the fall of 1977 has obtained no data to indicate activity
along Chatham Strait (Milne 1980). However, recent seismic hazard
studies completed in the area have included interpretations indicating
the fault as active (Converse Davis Dixon Associates 1978). The clos-
est approach of this fault to the project site is about 20 miles south-
southwest.
4.1.5 Chinakof-Baranof Fault
The Chinakof-Baranof fault is interpreted as a south-southeasterly splay
of the Fai rweather fault system at approximate 1 at itude 58°20 I. Numer-
ous epicenters located along its inferred trace indicates it is present-
ly an active seismic zone. Since it is so closely related to the Fair-
weather fault system and no divergent fault plane solutions were found
on the east side of that fault zone, it is reasonable to assume it is
also a transform fault (Milne and others 1978). The closest approach of
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this fault to the project site is approximately 100 miles to the south-
west in the vicinity of Cross Sound where the Peril Strait, Fairweather
and Chinakof-Baranof fault approximately merge.
4.1.6 Peril Strait Fault
The Peril Strait fault is interpreted as a splay of the Fairweather
fault system (Plafker and others 1967). Trending northwesterly, the
Peril Strait fault joins the Fairweather fault in the vicinity of Cross
Sound. Movement along the fault is right lateral and is interpreted
to be a part of the Pacific-North American plate boundary zone. Dis-
placement along the fault is approximately 11 kilometers since the late
Cretaceous. The closest approach of this fault to the project site is
approximately 100 miles.
4.1.7 Other Faults
The Chaix Hills. Coal Glacier and the Chugah-St. Elias faults are lo-
cated west of the project site on the order of 200 mil es. As shown on
Drawing 10, the area is characterized by a large number of earthquake
epicenters. They have been interpreted as thrust faults associated with
the Fairweather fault system (Plafker 1982). These faults should be
considered to be active.
The Boundry fault is also considered a splay off of the Fairweather
fault. The fault is presently interpreted as ancient. No movement was
noted along the fault as a result of the 1899 earthquake whose epicenter
is near the fault (Plafker 1982). Based on present evidence, this fault
is not considered to be active.
The King Salmon and Nahlin faults are located east of the project in
Canada. The Nahlin fault has been traced almost continuously for a dis-
tance of 250 miles. A minimum vertical displacement of 20,000 feet has
been speculated as taking place since middle Jurassic. The King Salmon
fault trends west-northwesterly, almost parallel and south of the Nahlin
fault. The King Salmon fault is interpreted as an old thrust fault and
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not presently active. An intrusion interpreted as being approximately
140 million years old cross cuts the fault and exhibits no faulting or
shearing (Souther 1972);
The Hubart fault (Art Lewis fault) is located north of Yakutat Bay. The
fault is consi de red an 01 d suture zone. The fault has been annealled by
an intrusive which is interpreted as being 140 million years old (Dodds
1982).
The Gastineau fault trends northwest through Gastineau channel near
Juneau to Berners Bay and into Lynn Canal.
the Lynn Canal and the Gastineau faults.
Most investigators connect
In the Juneau area careful
inspection of Pleistocene sediments has resulted in the conclusion that
no post-Pleistocene movement has taken place in that vicinity (Miller
1972).
4.2 REGIONAL LINEAMENTS
Throughout southeast Alaska there are numerous linear features repre-
sented by aligned topographic features such as valleys, drainage chan-
nels, fiords and straits. A large number of these features are repre-
sented by water courses. A plot of epicenter information and feature
location generally show little or no correlation. The major lineaments
within the region of the project are discussed below.
4.2.1 Coast Range Megalineament
The Coast Range megalineaments orginates approximately 50 miles south of
the West Creek project site at Point Sherman. The megalineament is a
major structural and topographic feature which roughly parallels the
western edge of the Coast Range Batholith Complex. From its junction
with the Chatham Strait-Lynn Canal fault at Point Sherman, it trends in
a southeasterly direction for 370 miles across southeast Alaska to Work
Canal and Chatham Sound-Grenville Canal in British Columbia (Twenhofel
and Sainsbury 1958, Brew and Ford 1978). Although there are areas of
limited lateral and vertical separation along the lineament, it does
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not appear to be a major fault structure but a zone of closely spaced
joints, foliation, compositional layering and small faults which has
been accentuated by fluvial and glacial erosion (Brew and Ford 1978).
This zone varies from a few meters to 6 miles in width, and more than
one major strand of the megal i neament has been recogni zed in several
areas. The most notable occurrence is the bifurcation of the main
strand just north of Endicott Arm. The more northerly splay trends
southeasterly along the arm rejoining the more southerly strand near
Thomas Bay. In 1929 the southern strand was mapped as a thrust fault
(Twenhofel and Sainsbury 1958). More recently a 5-to 15-meter wide
gouge zone has been mapped between quartzite units withi n a garnet-
biotite schist just south of this strand (Brew and Ford 1978). A 6-mile
right-lateral offset has been suggested based on the separation of zones
of equal grades of metamorphism; however, these zones are nearly verti-
cal and poorly controlled in the area. At Burroughs Bay near the north
end of Revillagigedo Island, a 0.5-mile gouge zone coincides with the
entrance of the lineament into Behm Canal. Holocene alluvial deposits
overlyi ng portions of thi s zone s how no evi dence of recent movement
(Berg 1980). South of Rudyard Bay where the lineament comes onshore,
field evidence indicates it is not a fault. Canadian investigations
have classified the southern extension of the lineament into the Work
Canal area of British Columbia as a fault.
As a surficial feature the Coast Range lineament is considered late
Pleistocene. Although no post-Pleistocene evidence exists to indicate
faulting was a major contributor to the formation of the lineament, it
may have occurred (Brew and Ford 1978). There is no strong evidence to
indicate that the lineament is active in areas where it is mapped as a
fault.
Recent interpretations as to the origin of the lineament suggest that
the Coast Range lineament is an upward projection of the deep-seated
boundary between relatively thin predominantly metamorphic crustal rocks
and the thicker, more granitic crust to the east (Brew and Ford 1978).
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4.2.2 Glacier Bay Lineament
The Glacier Bay lineament trends northwesterly from Chatham Strait
through Icy Strait and Glacier Bay. The basis for the lineament is ap-
parently the semi-linear trend of the waterways. Geophysical profiling
completed in the vicinity of the lineament has exhibited no evidence of
faulting or at least surface rupture (Plafker 1982).
4.3 REGIONAL SEISMICITY
Southeast Alaska and the west coast of Canada lie within a seismically
active zone. In the region of the West Creek Project the major earth-
quakes occur to the south and west towards the Pacific Ocean. A region-
al plot of earthquake epicenters, known faults, and lineaments are shown
on Drawing 10. The concentration of earthquake epicenters generally
occur westward from the general location of the Chilkat fault offshore
to the general vicinity of the Fairweather fault system. The Fairweath-
er fault is located offshore approximately 95 miles from the project
site. The Chilkat and Chatham Strait-Lynn Canal faults are located
approximately 20 miles from the project site.
The earthquake epicenters shown on Drawing 10 were obtained from list-
ings by National Geophysics and Solar Terrestrial Data Center of NOAA,
and from the Pacific Geoscience Centre, Earth Physics Branch, Department
of Energy Mines and Resources at Sidney, B.C., Canada. The earthquake
information is for the period starting 1899 and going up through 1978
for the Canadian listing and through 1980 for the NOAA listing.
The earthquake activity is believed to be actually higher than that pre-
sented. It is assumed that many earthquakes were not detected because
of the lack of stations and sparse population. Seismograph stations are
widely spaced. The Sitka, Alaska station has been in operation s'ince
1904. A station was installed at Whitehorse and at Kluane Lake in the
Yukon in 1975 (Lahr 1982).
Within a 100-mile radius of the project site, there have been a total of
approximately 128 seismic events recorded between 1899 and 1980. This
figure does not include 12 additional events which have been interpreted
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as representing duplications. Of the 128 seismic events, 55 were be-
tween magnitudes 2.5 and 3.4, 50 events between 3.5 and 4.4, 23 events
between 4.5 and 5.4, 8 events between 6.5 and 7.4, and one event greater
than 7.5. Within a 20-mile radius of the project site only four seismic
events have been recorded. These four events consist of two between
the magnitudes of 2.5 and 3.4, and one event each in the ranges of 3.5
to 4.4, and 4.5 and 5.4. In addition, a single event with a magnitude
range of 5.5 to 6.4 was recorded just beyond the 20-mile radius. Table
4-1 describes the Modified Mercalli scale.
In recorded history there have been numerous seismic events which have
been felt in the Skagway area (Yehle, Lemke 1972). A brief description
of the major events are listed below:
1899 In September of 1899, five earthquakes were felt in the Skag-
way area. The fi rst occurred on September 4 and was located
near Icy Bay, approximately 240 miles west of the project
site. An estimated intensity of VII has been given at Skag-
way and is reported to have caused severe shak i ng. On Sep-
tember 10, two earthquakes were reported felt causing cracked
chimneys and only two buildings were reported as escaping
damage. The epi centers for these earthquakes have been lo-
cated a short distance west of Yakutat Bay, approximately 170
miles west of the project site. On September 16th, an earth-
quake occurred which apparently resulted in submarine sliding
and damage to a Skagway dock. This was followed by another
quake on September 17th. A Seattle paper reported an earth-
quake occurring on October 4th which resulted in the shift-
ing of several building foundations in Skagway.
1900 On October 9, 1900 on earthquake occurred near Icy Bay and
very near the September 4,1899 epicenter. An assigned in-
tensity of VI to VII was given at Skagway. The earthquake
was located approximately 240 miles west of the project site.
1903 On July 26, 1903, an earthquake with a magnitude of 8.2 oc-
curred with an epi center 1 ocati on approxi mately 200 mi 1 es
west southwest of the project. Information does not indicate
any record that this earthquake was felt in Skagway.
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1909 On May 6, 1909 an earthquake with a magnitude of 7.0 occurred
with an epicenter near the Alaska coast and a short distance
south of Yakutat Bay. The epicenter has been located approx-
imately 148 miles west of the project site. There is no re-
cord that this earthquake was felt in Skagway.
1927 On October 24, 1927 an earthquake of magnitude 7.1 occurred
off the coast of Alaska along the Fairweather fault zone. Its
epicenter is approximately 155 miles south southwest of the
project site and offshore of Baranof Island. There is a
questionable account of this event being felt in the vicinity
of Skagway.
1944 On February 3, 1944 an earthquake of magnitude 6.5 occurred
along the Chilkat fault of the Denali fault system. This
event was located in the Yukon approximately 105 miles north-
west of the project site. There is a questionable account of
this event being felt in Skagway (Yehle 1972).
1958 On July 10, 1958 an earthquake of magnitude 7.9 occurred east
of Lituya Bay approximately 95 miles southwest of the project
site. This is the most recent earthquake to cause damage in
the Skagway area. Shaking was in a north-south direction an
caused some concrete foundations to crack and many landslides
occurred along the valley sides. Two abnormal sea waves
reached Skagway although no damage occurred to the harbor
facilities. However, submarine landslides caused submarine
communication cables to break. This earthquake broke the
surface in the vi ci nity of the epi center and accounted for
21-1/2 feet of right lateral movement and 3-1/2 feet of ver-
tical slip along the Fairweather fault.
1973 On July 1, 1973 an earthquake of magnitude 6.7 occurred off
the coast of Alaska near the north end of Baranof Island ap-
proximately 140 miles southwest of the project site. There
is no account of it being felt in Skagway. The event has
been associated with movement along the Fairweather fault
lone.
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4.4 PROJECT FAULTS AND LINEAMENTS
During this investigation for the West Creek Project and regional geo-
logic studies completed by others in the area, no faults have been
defined which have offset either Pleistocene or Holocene age sediments
(Yehle, Lemke 1972).
There are numerous linear features which have been identified in the
general project area. Many of these areas are reflected in linear
waterways, inlets or river valleys. Some of these lineaments have been
designated as inferred faults. If they are proven to be faults, it is
thought that they would be no older than middle Tertiary and no younger
than the last major Quaternary period of glaciation. No faults have
been observed in Quaternary deposits (Yehle and Lemke 1972). The larger
of the features consist of the inferred Chilkoot Inlet fault, Ferebee
River lineament, Taiya River lineament, Skagway River lineament, and
the Katzeh i n River Delta-Upper Dewey Lake 1 i neamant. These featu res
generally are interpreted to be northern extensions of the Lynn Canal-
Chilkoot Inlet lineaments.
The inferred Chilkoot fault trends northwestward, parallel and beneath
the Chilkoot River Valley. In addition to the linear nature of the
valley, large bedrock landslides have been reported which may suggest
faulting (Yehle 1982). However, recent mapping in the area indicates no
offset in geologic units across the valley. In addition, geophysical
profiling in the Chilkoot and Lutak Inlets have produced no evidence of
faulting (Plafker 1982).
The inferred Ferebee and Taiya River faults are based solely on the
evidence of linearity. No direct evidence is available at this time
which indicates a fault. Like the inferred Chilkoot fault, the geology
is reported to be continuous across the Ferebee and Taiya valleys. In
addition, geophysical profiling in the Taiya and Chilkoot Inlets reveal
no evidence of faulting (Plafker 1982).
The inferred Skagway River fault parallels and lies beneath the Skagway
Valley. As with the other inferred faults, the evidence is indirect and
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is primarily based on the linearity of the valley. North in Canada, the
feature merges with other structures whi ch have been mapped as faults
(Yehle, Lemke 1972).
The Katzehin River Delta-Upper Dewey Lake lineament is represented by a
very promi nent north-trendi ng 1 i neament. The feature can be traced for
approximately 35 miles from the Katzehin River Delta on the Chilkoot
Inlet, northward and parallel with the Taiya Inlet through Upper Dewey
Lake, Goat Lake and northward into Canada. The trend of this feature
approximates the general trend of regional joint sets (Yehle, Lemke
1972) •
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TI'8LE 4-1
r.w I F I ED Mrn:ALLI I NTENS I TY SCALE OF 1931
I. Not felt except by a very few under especially favorable clrcllllStances.
II. Felt only by a few persons at rest, especially on upper floors of buildings. Delicately
suspended objects may swing.
I I I. Felt quite noticeably Indoors, especially on upper floors of buildings, but many people
do not recognize It as an earthquake. Standing rotor cars nay rock sl ightly. Vltratlon
like passing of truck. DJratlon estimated.
IV. During the day felt indoors by many, outdoors by few. At night sane awakened. Dishes,
wlndaols, doors disturbed; walls make creaking sound. Sensation like heavy truck striking
building. Standing notor cars rocked noticeably.
V. Felt by nearly everyone; many awakened. Some dishes, wlndaols, etc., troken; a few In-
stances of cracked plaster; unstable objects overturned. Disturbance of trees, poles,
and other tall objects sometimes noticed. Pendullll\ clocks may stop.
VI. Felt by all; many frightened and run outdoors. Some heavy furniture roved; a few In-
stances of fal len plaster or damaged chimneys. Damage slight.
VII. Everybody runs outdoors. Darrage negligible In wildings of good design and construction;
slight to rncxIerate to well-built ordinary structures; considerable In poorly build or
bad I Y des I gned structures; sane ch I mneys troken. Not I ced I:1t persons dr I v I ng notor cars.
VIII. Damage slight In specially designed structures; considerable In ordinary substantial
buildings with partial collapse; great in poorly built structures. Panel walls throm
out of frame structures. Fall of chlrmeys, factory stacks, coll.rms, roonuments, walls.
Heavy furniture overturned. Sand and mud ejected in small arrounts. Changes In well
water. Disturbed persons driving rotor cars.
IX. Darrage considerable in specially design structures; well designed frame structures throm
out of plumb; great In substantial bUildings, with partial collapse. Buildings shifted
off foundations. Ground cracked conspicuously. Underground pipes troken.
X. Sane well-built wooden structures destroyed; rost masoory and frame structures destrOfed
with foundations; ground badly cracked. ~ils bent. Landslides considerable from river
banks and steep slopes. Sh I fted sand and mud. Water sp lashed (s lopped) over banks.
XI. Few, If any, (masonry) structures renaln standing. Bridges destrOfed. Bread fissures In
ground. Underground pipelines completely out of service. Earth slumps and land sl Ips in
soft ground. Ralls bent greatly.
XII. Il3mage total. Waves seen on ground surfaces. Lines of sight and level distorted. Ob-
jects thrOfin u~ard Into the air.
See (Wood and Newmann 1931) for complete detai Is of this Modified Mercal I I Intensity Scale.
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5. PROJECT GEOLOGY
The West Creek drainage had been investigated by the United States Geo-
logical Survey in 1962 as a potential hydroelectric site. The investi-
gation consisted of a reconnaissance-level geologic examination of a
possible dam site, reservoir area, and the area of appurtenant struc-
tures. The 1962 study identified a dam site which is approximately the
same as to that investigated during this investigation. The results of
the Geological Survey investigation indicate a generally favorable con-
clusion from a geotechnical standpoint for hydroelectric development of
the drainage (Callahan, Wayland 1965).
The West Creek Project would be located in the West Creek drainage near
its confluence with the Taiya River. The West Creek drainage is approx-
imately 10 miles in length and flows easterly into the Taiya River.
Approximately 3 miles downstream of the confluence of West Creek, the
Taiya River empties into Taiya Inlet. Taiya Inlet is a long, narrow
fiord-like extension of Chilkoot Inlet and Lynn Canal. The West Creek
Valley bifurcates in its upper reaches and glaciers occupy each of the
valleys. In the area of the dam site, a bedrock ridge trends diagonally
across the valley generally dividing the drainage into two distinct geo-
morphic areas. Between the upper reaches of the drainage and the bed-
rock ridge, the valley is steep-walled with a valley floor characterized
as being relatively broad, poorly-drained and with very little relief.
This flatter portion of the valley has an elevation change of approxi-
mately 125 feet in a distance of about three miles. The gradient is
somewhat steeper further upstream. Downstream of the dam site, West
Creek is generally located in a bedrock channel with an elevation change
of about 590 feet in approximately 2-1/2 river miles.
The project location is underlain by granodiorite bedrock belonging to
the multi-phase batholith complex of Cretaceous age which intruded
Paleozoic to Mesozoic age metamorphic rock units (Brew, Morrell 1980).
These metamorphic units are now only preserved as roof pendants and thin
layers within the intrusive complex. The last major orogeny, which
began during the early Tertiary time, has caused uplift, folding and
faulting, resulting locally in a complex structural configuration.
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Glacial action in the West Creek drainage has resulted in the general
scouring of the landform, including the removal or modification of any
pre-glacial soil mantle. In addition, it is probable that near-surface
zones of weak, weathered and/or fractured rock was removed by scour and
plucking. The most obvious effect of the glacial action has been the
overdeepening of the upper West Creek drainage. Based on a projection
of the valley walls, it is anticipated that the thickness of sediments
in the upper valley could be well in excess of 200 feet. After the
retreat of the glacier, the ridge near the dam site formed a barrier
resulting in the formation of a lake. Eventually, the water spilled
over the ridge and subsequently channelized in its present location.
Glacial debris and alluvium slowly filled the lake basin to its present
level. The level of infilling was controlled by the creek channel ele-
vation near the dam site.
5.1 BEDROCK
Bedrock is generally exposed a round the peri meter of the reservoi r,
within the area of the dam site, powerhouse and along the major portion
of the West Creek channel downstream of the dam site.
The predomi nant rock types withi n the project are granit i c crystall i ne
rocks, primarily granodiorite. Previous investigation identified small
exposures of diorite. Diorite was identified by petrologic examination
of core recovered from boring DH 104. Several fine-grained mafic dikes
which intrude the granodiorite have been observed in borings and outcrop
exposu res. They have been obse rved as rang-j ng in si ze from one to fi ve
feet in thickness.
Physically, the granodiorite is light gray, medium-grained, hard,
slightly weathered to unweathered with widely-spaced fractures. Some of
these fractures have been hydrothermally altered and/or weathered pro-
ducing a gray-green or orange color in the granodiorite. The mafic
dikes are of andesite composition, gray green in color, fine-grained,
slightly weathered to unweathered and hard with medium to closely spaced
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fractures. The general trend of these dikes is N5°E to N500E and dip-
ping 60° to 80 0S. The age of these dikes are thought to be Quaternary
(Barker 1952).
Three joints sets have been identified. The primary joint set trends
between N65°E and N800E and dips between 60° and 85° to the south. A
secondary joint set strikes between N300E and N35°E and dips between 60°
and 85° to the south. Another secondary joint set trends between N35°W
and N45°W and dips approximately 80° either side of vertical. In the
powerhouse area, another joint set was identified trending approximately
north-south and di ppi ng between 55° and 70° to the east. The stri kes
and dips of joints are average values and joints other than those noted
are present. In addition to these tectonic joints, it is anticipated
that irregular jOints not associated with the major sets as well as
relief or sheeting joints will be present. These joints generally are
parallel or subparallel the to rock surface and are the result of
exfoliation or stress relief.
Detailed examination of the surface exposures and rock core indicated
fracture spaci ng rangi ng from very wi dely to extremely close-spaced.
Extremely close-spaced fractured rock was generally encountered beneath
areas marked by surface lineaments. These zones are anticipated to vary
in width from a few feet to approximately 100 feet.
5.2 OVERBURDEN
In general, the bedrock is mantled with varying thicknesses of overbur-
den materials. The overburden thickness is generally less on the valley
walls and downstream from the dam site to the powerhouse sites. Thin
deposits, on the order of a few feet, generally mantled most of the area
which is indicated as bedrock on the geologic maps. The thicker over-
burden deposits are located in the proposed reservoir area and along
West Creek approximately midway between the dam and powerhouse sites and
in the Taiya River Valley. These overburden materials include terrace
deposits, glacial moraines, recent alluvium and talus deposits. A very
limited exposure of glacial drift was observed near the dam site.
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5.2.1 Glacial Drift
The oldest exposed overburden unit observed at the project site is
gl aci al dri ft. A small exposure of gl aci al dri ft was observed in the
vicinity of the right dam abutment. It is thought to be a relic of a
!'lore extensive deposit which was subsequently eroded by West Creek.
Glacial drift is very dense, unstratified mixture of silt, sand and
gravel with some cobbles and was deposited directly beneath the glacier.
Overriding by glacial ice resulted in overconsolidation of these sedi-
ments.
5.2.2 Terrace Deposits
Terrace deposits are present in the vicinity of the bend in the river
approximately one-half mile downstream of the dam site and in the vicin-
ity of alternative powerhouse 3. The deposits near the river bend are
poorly exposed and are not anticipated to be of great thickness. The
depos its near a lternat i ve powe rhouse 3 a re most pronounced with moder-
ately well-defined terrace levels at approximate elevations of 300, 200
and 100 feet. These depos its are well exposed in roadcuts of the West
Creek access road. In these exposures, the terrace deposits consist
primarily of dense sand, silty sand and gravel. Based on the projection
of the bedrock surface, these deposits may range upwards of 100 to 150
feet in thickness.
5.2.3 Glacial Moraines
Lateral and end moraine deposits are present in the upper West Creek
drainage and are actively being deposited by glaciers. The deposits
consist of a homogeneous mixture of clay, silt, sand and gravel with
numerous boulders.
An overburden deposit in the vicinity of alternative powerhouse 2 has
been tentatively identified as a morainal deposit. Based on the results
of borings DH 109 and DH 110 and limited surface exposures, the deposit
consists of subangular to subrounded boulders up to three feet in diam-
eter with a matrix of silt, sand and gravel. The deposit forms a bulge
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on the west side of the Taiya Valley at the mouth of West Creek. With
the exception of this deposit, the west wall of the Taiya Valley is
relatively uniform. Based on the results of the drilling and a seismic
refraction study, the deposit ranges upwards of 100 feet in thickness.
A thickness of 117 feet was encountered in boring DH 109. Low compres-
sional wave velocities determined during the seismic refraction study
indicate that the material is relatively loose and probably of low den-
sity. Several well-developed terrace levels were observed at approximate
elevations of 250 feet, 175 feet and 45 feet indicating the deposit has
been modified by flowing water.
5.2.4 Alluvium
Recent alluvium is present in the West Creek drainage upstream of the
proposed dam site and in limited amounts in the existing creek channel.
In addition, there are some small exposures a short distance downstream
from the dam site. The Taiya River Valley is also underlain by recent
alluvium. Exposures of the recent alluvium are limited. However, based
on these exposures, the alluvium consists of bedded deposits of sand,
gravel and cobbles with varying amounts of silt. In the upper West
Creek drainage and upstream of the dam site, it is anticipated that the
coarser sand and gravel which is exposed at the surface will be under-
lain at depth by finer-grained lacustrine deposits. An electrical resis-
tivity survey completed as part of the borrow exploration indicates that
the boundary between the coarse-and fine-grained sediments may be on
the order of 25 feet below the ground surface.
5.2.5 Talus Deposits
Upstream of the dam site and in the proposed reservoir area, the lower
valley sides are mantled with cone-shaped deposits of talus. Talus de-
posits primarily consist of rock fragments ranging from sand size to
several feet in size. There is generally a matrix of loose soil between
the rock fragments. The surface of the deposits is generally steep with
slopes near their natural angle of repose. The source of the rock frag-
ments is the bedrock exposures higher up on the valley sides. The rock
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fragments become detached by the freezing and thawing of water which has
penetrated the fractures of the bedrock. It is anticipated that these
deposits may reach a maximum thickness of several tens of feet.
5.3 DAM SITE
Geologic conditions at the dam site were explored by surficial mapping,
air photo interpretation and six borings, DH 102 through DH 107. In ad-
dition, five seismic refraction traverses, SL-6 through SL-10 were com-
pleted in the damsite area. The location of the explorations and dam
site geology is shown on Drawing 5. The location and orientation of the
borings were selected to explore specific features such as surface line-
aments and conditions beneath the West Creek channel.
5.3.1 Geology
Bedrock is interpreted as being at or very near the ground surface in
the general vicinity of the dam site. Generally, there is a thin mantle
of overburden in the form of talus, alluvium and/or organic debris.
Bedrock outcrops are generally restricted to steeper slopes and the area
immediately adjacent to the West Creek channel. The predominant rock
type at the dam site area is granodiorite. A thin, approximately 4-foot
wide andesite dike was encountered in boring DH 102.
The major structural property of the bedrock is the joi nt sets. Three
joint sets were identified in the area of the dam site and are summar-
ized in a joint rosette on Figure 5-2. The joint rosette is an upper
hemisphere polar joint plot and its derivation is shown on Figure 5-1.
The two primary joint sets strike approximately N700E and N300E and dip
between 70° and 80° toward the south. A less prominent joint set was
a 1 so obse rved. This less prominent joint set strikes approximately
N35°W and dips either side of vertical. The presence of a low angle
joint was occasionally observed. This is not interpreted as a true
tectonic joint, but a parting in the bedrock which is caused by exfolia-
tion and/or stress relief. These joints or fractures are anticipated
to be a near-surface characteristic and to roughly parallel the bedrock
surface.
Converse Consultants, Inc.
The attitudes of joint
planes are represented
by a reference sphere
used to define dips
and strike of joint
planeSln space in
Figure 1. The shaded
edge portion of this
plane is known as the
great circle, which
uniquely defines the
dip and strike of the
joint plane in space.
Since the same infor-
mation is given on
both upper and lower
parts of the sphere,
only one of these need
be used and, in engi-
neering applications,
the upper hemisphere
is used shown in Fi-
gure 2.
In addition to the
great ci rcl e, the i n-
clination and orien-
tation of the joint
pl ane can al so be de-
fi ned by the ~ of
the joint plane. The
pole is the point at
whi ch the surface of
the sphere is pierced
by the radi al 1 i ne
which is normal to the
joint pl ane.
In order to communi-
cate the information
gi ven by the great
circle and the posi-
tion of the joint pole
on the surface of the
upper hemisphere, a
two-dimensional repre-
sentation is obtained
by projecting the in-
formation onto the
hori zonta 1 reference
pl ane known as pol ar
equal-area stereonet
shown in Figure 3.
Great Circle
Figure 1
Figure 2
Figure 3
Reference Sphere
Great Circle
Pole
Projection
of Joint Pole
Vertical
Projection
Line
EXPLANATION OF UPPER HEMISPHERE POLAR JOINT PLOT
Alaska Power Authority
WEST CREEK PROJECT
for ~.W. 8eck and Associates, Inc. ------------------------
Converse Consultants
Project No.
81-5165
Figure No.
5-1
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o
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::J
Q.
~
.2
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2
Q.
Q. «
., ,..
'-'" on o
o
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"-
UPPER HEMISPHERE POLAR PLOT
N
w
S
LEGEND
---1.0 --% of joint poles within contour
Total Population: 499 joint attitudes
JOINT ROSETTE-DAM SITE
Alaska Power Authority
WEST CREEK PROJECT
for K.W. 8eck and Associates, Inc.
~--------------------
Converse Consultants
E
PrOject No.
81-516::i
5-2
-35-
The left abutment area was explored by three borings, DH 102 through DH
104, and by seismic refraction traverses SL-6 and SL-8. Boring DH 104
was inclined beneath the West Creek channel. Bedrock is exposed at the
surface or was encountered at shallow depths. The bedrock is generally
fresh below a depth of 5 feet and contains widely-spaced fractures and
occasional zones of closely-spaced fractures. A gray-green, medium
fractu red, andes i te di ke was encountered between approxi mate dept hs of
40 to 45 feet in boring DH 102.
The right abutment was explored by three borings, DH 105 through DH 107,
and seismic refraction traverses SL-7, SL-9 and SL-10. Similar to the
left abutment, bedrock is exposed at the surface or was encountered at a
shallow depth. The bedrock is generally fresh below 5 feet with widely-
spaced fractures and occasional zones of extremely close fractures with
some being slickensided and infilled with clay. In addition, there are
zones of medium hard rock which have been hydrothermally altered. Bor-
ings DH 105 and DH 107 were oriented to intersect the subsurface exten-
sions of surface lineaments. The lineaments are interpreted as the
surface expression of rock having a lower quality. Boring DH 107 en-
countered zones of very closely fractured and/or sheared rock beneath
the general areas of surface lineaments. Some of the very close frac-
ture zones exhibited slickensided fractures with gouge and clay infill.
Geologic conditions beneath the West Creek channel were explored by bor-
ing DH 104. This boring was located on the left abutment and inclined
beneath the creek channel. An extremely closely fractured and/or shear
zone was encountered between approximately 140 feet and 155 feet along
the drill hole. This zone is located beneath the active creek channel
and along with the linearity of the West Creek channel suggests that the
creek may be structurally controlled.
Based on interpretation of the boring data, the estimated depth to sound
rock below the rock surface measured at right angles to the rock surface
ranges between zero and 5 feet on the right abutment and 5 to 10 feet on
the left abutment. An approximate sound rock line is shown on the dam
site section, Drawing 6.
Converse Consultants, Inc.
-36-
As previously indicated. there is generally a thin mantle of overburden
over the bedrock. Immediately upstream of the dam site. the thickness
of overburden increases. Based on the results of seismic refraction
traverse SL-6. bedrock dips steeply downward in an upstream direction.
The seismic information indicates that the overburden thickness is on
the order of 85 feet near the upstream end of the traverse. Based on
limited exposures. this alluvium is anticipated to consist primarily of
sand and gravel with possibly silt and clay at depth. A relatively
small area of alluvium was mapped downstream of the dam site between an
approximate distance of 500 and 1.400 feet. Alluvium is also present in
the act i ve stream channel. The results of bori ng DH 104 near the dam
site indicate that a deep erosional channel does not exist in that area.
The depth of river alluvium is still to be determined. However. for
use in preliminary estimates. a thickness of 20 feet can be used. The
actual thickness of the alluvium could be considerably more than 20
feet.
5.4 SPILLWAY
Two potential spillway sites have been identified. The initial site is
located in a topographic low on the left abutment. north of the proposed
dam axis. The alternative spillway site is located on a topographic
bench on the right abutment a short distance south of the proposed dam.
5.4.1 Left Abutment Spillway
The left abutment spillway was explored by geologic mapping. boring DH
101. and seismic refraction traverse SL-5. Boring DH 101 was oriented
so as to cross the primary joint set at approximately a right atlgle and
to explore at depth a potential surface lineament.
Bedrock is well exposed along the margins of the topographic low on the
steeper slopes. The bedrock. like elsewhere. consists of a granodio-
rite. slightly weathered and hard with generally widely-spaced frac-
tures. The results of the seismic refraction traverse and boring DH 101
Converse Consultants. Inc.
-37 -
indicate that where overburden exists, it is relatively thin and only
a few feet in thickness. The presence of occasional potholes in the
bedrock su rface suggests that thi s topographi c low was probably a hi gh
level outlet for a proglacial lake prior to the establishment of West
Creek in its present channel.
5.4.2 Right Abutment Spillway
The alternative right abutment spillway site was explored by geologic
mapping, borings DH 105 through DH 107, and by seismic refraction tra-
verses SL-7, SL-9 and SL-10. Borings DH 105 and DH 106 were oriented so
as to cross the primary joint sets and to explore at depth a surface
1 i neament.
Bedrock is exposed only on a few steep slopes. In other areas, bedrock
is mantled with a thin layer of overburden. At the boring locations,
the thickness of overburden ranges from approximately 2 to 10 feet.
Based on the interpretation of the seismic refraction traverses, the
overburden thickness generally ranges between 5 and 10 feet. At the
boring locations, the overburden consisted of a surface layer of forest
duff underlain by medium dense silty sand or sandy silt. Boring DH 107
encountered a hydrothermally altered and extremely to very closely frac-
tured zone between approximately 37 and 41 feet, and between 49 and 58
feet, as measured in the hole. It is thought that these altered and
fractu red rock zones may be the reason for the topographi c 1 i neament
observed at the ground surface.
5.5 WEST CREEK DIVERSION
It appears likely that West Creek could be diverted by either a diver-
s ion tunnel or possi b ly by channel i ng through the dam structure. Topo-
graphically and physically, it appears that a diversion tunnel could be
driven in either abutment. No exploration other than the damsite
borings, seismic refraction surveys and geologic mapping was completed
relative to the diversion structure.
Converse Consultants, Inc.
-38-
5.5.1 Geology
Bedrock is exposed intermittently throughout the general damsite area.
The exception to the thin overburden is upstream of the dam axis on the
left abutment where seismic refraction traverse SL-6 indicates that the
bedrock surface dips steeply downward in an upstream direction with
overburden thickness ranging upwards of 85 feet. On the right abutment,
the results of boring DH 107 and seismic refraction traverse SL-7 indi-
cate that bedrock is covered by a generally thin mantle of overburden,
on the order of 5 to 10 feet thick.
Bedrock in the area of the diversion structure is anticipated to be the
same as that described for the dam site, i.e., granodiorite, slightly
weathered to unweathered, hard, with widely-spaced fractures. Zones of
closely or extremely closely fractured rock are anticipated along with
occasional andesite dikes.
5.6 POWER TUNNEL
Four potential power tunnel alternatives are being considered. Alterna-
tives 1, 2 and 3 are located south of West Creek while alternative 4 is
located north of West Creek. All alternative schemes include a surge
tank or shaft near the powerhouse end of the tunnel. Alternat i ves 1, 2
and 3 consist of the same alignment between the dam site and surge tank.
The variation occurs downstream of the surge tank where the alignment is
governed by the selected powerhouse scheme. Power tunnel alignments 1
and 2 connect to powerhouse sites on the south side of Falls Creek while
power tunnel alignment 3 swings northward crossing beneath West Creek
connecting to a powerhouse site on the north side of West Creek. Power
tunnel alternative 1 is combined with a short downstream surface pen-
stock to the powerhouse. Power tunnel alternative 4 is located north of
West Creek and connects to the powerhouse site on the north side of West
Creek.
At the time of the field investigations, only the alternatives on the
south side of West Creek had been identified. Thus, the field investi-
gation program was directed to these alignments.
Converse Consultants. Inc.
-39-
5.6.1 Geology -Alternatives 1 through 3
Exploration in the vicinity of the proposed power tunnel alignments 1
through 3 consisted of explorations at the dam site and the powerhouse
sites, boring DH 108 at the surge tank, aerial photographic interpreta-
tion, and a reconnaissance-level geologic traverse along the general
al i gnment.
Between the dam site and the surge tank, bedrock is exposed intermit-
tently at the ground surface. In general, the overburden is anticipated
to consist of a surface layer of forest duff underlain by colluvial
soil. Talus deposits were observed in some areas and their thickness is
anticipated to range up to several tens of feet. Based on the informa-
tion presently available, it is judged that the tunnel alignment between
the dam site and surge tank will be entirely within bedrock. The bed-
rock is expected to be granodiorite with numerous dikes crossing the
alignment. Rock quality is anticipated to be highly variable ranging
from wi dely-spaced to extremely closely-spaced fractures. A joi nt ro-
sette summarizing joint attitudes observed along the general alignment
is shown on Figure 5-3. The joint attitudes correspond closely with
those obtained in the vicinity of the dam site and powerhouses. The
primary joint sets strike approximately N300E and N45°W and dip 60° to
85° to the south and 80° to vertical to the north, respectively. A
secondary joi nt set stri kes approximately N65°E and di ps to the south
between 80° and 85°. As previously mentioned, a less prominent joint or
parting in the rock is anticipated to parallel the rock surface as a
relief joint. This joint is a result of exfoliation probably due to
removal of overlying rock rather than tectonic in nature.
The tunnel alignment will cross beneath several lineaments which have
been identified both in aerial photographs and during the geologic field
reconnaissance. In the field, the lineaments appear as a linear topo-
graphic low. Generally, bedrock is exposed on the steeper slopes of the
low, but seldom if ever in the bottom of the low. Most of the linea-
ments are parallel or subparallel to the primary joi nt set and may rep-
resent zones of closer-spaced joi nts and/or sheari ng. The ant i ci pated
lower quality of rock probably has made these areas more susceptible to
Converse Consultants, Inc.
UPPER HEMISPHERE POLAR PLOT
N
W
S
LEGEND
--3.0 % of joint poles within contours
Total Population: 133 joint attitudes
N45W
/80 0 -gooN
E
JOINT ROSETTE-POWER"TUNNEL ALTERNATIVE
Alaska Power Autllority
WEST CREEK PROJECT
for R.w. Beck and Associates, Inc.
Converse Consultants
Protect No.
81 <.i 16:5
Figure No.
5-3
-40-
erosion and ultimately resulted in the surface formation of the linea-
ment. In several areas, andesite dikes were noted as paralleling the
joint sets. It is possible that at least some of the lineaments may
represent zones where dikes or dike swarms are present and differential
weathering and erosion has resulted in the creation of the surface line-
aments. In addition, a lineament identified both on aerial photographs
and in geologic mapping crosses the tunnel alignment at an approximate
right angle approximately 2,000 feet downstream of the dam site. This
lineament or series of parallel lineaments, as viewed in high altitude
aerial photographs, can be traced for approximately 12 miles. At least
one of the lineaments is interpreted as paralleling West Creek in the
area where the course of the creek makes a sharp bend. This correlation
strongly suggests that this port ion of West Creek may be structurally
controlled. Several exposures of hi ghly fractured, sheared and/or al-
tered bedrock were observed along the creek channel in this area. An
extension of this lineament was inspected on the hillside north of West
Creek. At this location, it has a trend of approximately N5°E and dips
approximately 85° to the west. The zone is approximately 100 to 150
feet in width and consists of medium hard to soft, hydrothermally al-
tered granodiorite with extremely close fractures, some of which exhibit
slickensides with infillings of mylonite and clay gouge. Based on pre-
sent information, this feature has been classified as a fault. The pre-
vious investigation by the United States Geological Survey described the
feature as an inferred fault.
As previously indicated, the alternative power tunnel alignments diverge
downstream of the surge shaft. Power tunnel alternative 1 connects to
alternative powerhouse 1 approximately 1,000 feet south of West Creek as
shown on Drawings 3, 4 and 7. Bedrock is exposed intermittently along
this alignment. Overburden is anticipated to be relatively shallow and
consist of a surface mantle of forest duff underlain by either colluvium
and/or talus deposits. This tunnel alignment will be parallel to near
parallel to the primary joint set and to the trend of the lineaments
mentioned above. The downstream portal area of power tunnel alternative
1 was explored by seismic traverse SL-4 and SL-12, and by borings DH 111
and DH 112.
Converse Consultants, Inc.
-41-
Power tunnel alternative 2 connects with powerhouse alternatives 2-1 and
2-2 adjacent to and on the south side of West Creek. Similar geolog-
ic conditions are anticipated along most of the alignment with the ex-
ception of the extreme downstream portion. Geologic mapping, seismic
refraction traverses SL-1 through SL-3 and borings OH 109 and DH llO
confirm the presence of a thick overburden deposit which has been tenta-
t i vely interpreted as a gl aci al mora i ne. These are only very poor ex-
posures of this deposit. Borings DH 109 and DH llO indicate that the
deposit consists of gravel and boulders with a sand and silt matrix.
Low compressional wave velocities determined during the seismic refrac-
tion studies suggest that the material is loose or has a low density.
Borings DH 109 and DH 110 encountered approximately 90 and 120 feet of
overburden overlying bedrock, respectively. The deposit has several
terrace levels which indicates modification by flowing water. Both
borings DH 109 and DH 110 encountered primary andesite rock with minor
amounts of granodiorite. The limited amount of granodiorite may mean
that the borings were drilled along dikes or that a substantial amount
of andesite or a swarm of andesite dikes underlie the area. The tunnel
alignment in this area will be parallel to subparallel to the primary
joi nt set.
Power tunnel alternative 3 trends northeastward from the surge tank lo-
cation, crossi ng beneath the West Creek channel to powerhouse alterna-
tive 3 on the north side of the creek. Exploration along this alignment
consisted of geologic mapping and the completion of a single seismic
refraction traverse, SL-11, in the vicinity of the proposed powerhouse.
Bedrock is ant i ci pated to be at or near the ground su rface in the area
north of West Creek. An alluvial terrace mantles the major portion of
the area on the north side of the creek with the exception of the imme-
di ate a rea of the proposed powerhouse. The overburden, where exposed,
consists primarily of interbedded sand and gravel. The thickness of the
alluvium is not known. However, it is anticipated that bedrock would be
encountered at the proposed tunnel level. Rock is exposed at the ex-
treme downstream end of the alignment and in this exposure, the rock is
slightly weathered and hard with widely spaced joints or fractures.
Converse Consultants, Inc.
-42-
5.6.2 Geology -Alternative 4
Power tunnel alternative 4 was not identified until after the field
portion of the investigation had been completed. Thus, the exploration
for this alignment consists primarily of interpretation of aerial photo-
graphs and geologic mapping relative to the dam site and alternative
powerhouse 3.
Although some talus deposits are present in the area, it is anticipated
that a tunnel along the proposed alignment would probably be located
entirely in bedrock. In addition, it is likely that bedrock conditions
will be similar to those along the southern alignment. The upstream
portion of the alignment will be parallel to the secondary joint set.
5.7 INTAKE
An intake structure will be located upstream of the dam site and on
either the north or south side of West Creek depending upon which of the
power tunnel alignments is selected.
5.7.1 Geology
The proposed intake in the right abutment was explored by geologic map-
ping, boring DH 107, and seismic refraction traverse SL-7. Based on
this information, subsurface conditions are anticipated to consist of a
thin mantle of overburden overlying bedrock. Boring DH 107 and seismic
traverse SL-7 indicate that the overburden may range in thickness be-
tween 5 and 10 feet. There are no exposures of the overburden or bed-
rock at the intake location. Overburden in boring DH 107 consisted of
medium-dense silty sand. Bedrock encountered in the boring consisted of
generally unweathered, hard granodiorite with widely-spaced fractures.
The bori ng di d encounter some sheared and extremely close fractured
zones which have been hydrothermally altered. Geologic mapping indi-
cates the presence of alluvium on the west side of a small stream near
the west end of the intake area.
Converse Consultants, Inc.
-43-
The proposed intake for tunnel alternative 4 is located along the north
side of West Creek and upstream of the dam site approximately 800 feet.
Exploration at the site consisted of geologic mapping. Bedrock is ex-
posed in the vicinity of the back portion of the proposed intake and
consists of a slightly weathered, hard, granodiorite with widely-spaced
fractures. The ground surface in the southwestern portion of the pro-
posed intake area is relatively flat-lying and underlain by alluvium.
The bedrock surface is anticipated to slope steeply downward in a west-
erly direction. The near-surface portion of this alluvium is antici-
pated to consist of sand and gravel possibly underlain by finer-grained
silts and clays.
5.8 SURGE SHAFT
A surge shaft is planned approximately three-quarters of the way along
the tunnel ali gnment and near the powerhouse. Present des i gn i ndi cates
that the shaft will be vertical, approximately six feet in diameter, and
will extend from the tunnel to near the ground surface.
5.8.1 Geology
Exploration of the surge shaft area consisted of geologic mapping and
boring DH 108. As previously indicated, the northern tunnel alignment,
alternative 4, and its surge tank were not identified until after com-
pletion of the field investigation phase.
There are no exposures of bedrock or overburden in the immediate vicin-
ity of the surge tank location. However, the terrain suggests that the
overburden is relatively thin. The closest bedrock outcrop observed is
approxi mate ly 300 feet from the shaft 1 ocat ion. Bori ng DH 108 encoun-
tered approximately 17 feet of overburden consisting of angular cobbles
and boulders with some sand matrix. It is possible that the actual bed-
rock surface is somewhat shallower and portions of that classified as
cobbles and boulders may be highly fractured bedrock. The bedrock en-
countered in the drill hole consisted primarily of unweathered, hard,
granodi ori teo Genera" y, the rock exh i bited wi dely-spaced fractu res
with approximately one-half of the drill core being recovered as intact
Converse Consultants, Inc.
-44-
10-foot sections. However, several zones of mediu~ to closely fractured
and weathered rock were encountered. The major zones were between depths
of 66.5 feet and 79.5 feet, 103.3 feet and 128.0 feet, and 373.0 feet
and 414.0 feet. It is possible that at least some of these more frac-
tured rock zones may reflect the subsurface intersection of lineaments
which have been identified on the surface.
Little information is known about the geology at the surge tank location
on the north side of the West Creek. An interpretation of the aerial
photograph suggests that bedrock is probably at or near the ground
surface.
5.9 POWERHOUSE
Four alternative powerhouse locations have been defined. Alternatives
1, 2-1 and 2-2 are located on the south side of West Creek while alter-
native 3 is located north of West Creek. Powerhouse alternative 1 is
located approximately 1,000 feet south of West Creek and along the west
wall of the Taiya River Valley. Powerhouse alternative 2-1 is located a
short distance south of West Creek and at the confluence of West Creek
and Taiya River Valleys. Powerhouse alternative 2-2 is located in the
same general vicinity and approximately 100 feet further east. Power-
house alternative 3 is located a short distance north of West Creek.
5.9.1 Powerhouse Alternative 1
Exploration at the powerhouse alternative 1 site consisted of geologic
mapping, borings DH 111 and DH 112, and seismic refraction traverses
SL-4 and SL-12.
Bedrock is exposed in the general vicinity of the powerhouse site and
consists of slightly to unweathered, hard granodiorite. Overburden on
the valley wall consists primarily of talus with a thin surface mantle
of forest duff. Bedrock encountered in boring DH 111 was relatively
unweathered while the upper 22 feet of boring DH 112 was more fractured.
The upper portion of seismic refraction traverse SL-12 indicates an
intermediate velocity layer which is interpreted as representing the
Converse Consultants, Inc.
c o
.~
.~
:0
::J a.
CI ,..
'-
'" .,
o
o z
::l
II: o
I.L
UPPER HEMISPHERE POLAR PLOT
N
w +
LEGEND
--1.9---% of joint poles within contour
Total Population: 104 joint attitudes
JOINT ROSETTE-POWERHOUSE ALTERNATIVES
Alaska Power Authority
~EST CREEK PROJECT
for R.W. Beck and Associates, Inc.
Converse Consultants
PrOject No.
31-5165
Figure No.
5-4
-45-
more fractured zone. The Taiya River floodplain lies immediately adja-
cent to the proposed powerhouse location. Based on the results of the
seismic refraction lines, the bedrock surface slopes downward beneath
the Taiya River floodplain at approximately the same slope as on the
valley wall. The floodplain sediments are anticipated to consist pri-
marily of sand, sand and gravel, and interbedded sand and silt.
5.9.2 Powerhouse Alternatives 2-1 and 2-2
Exploration at powerhouse alternatives 2-1 and 2-2 consisted of geologic
mappi ng, bori ngs DH 109 and DH 110, and seismi c refract ion traverses
SL-1 through SL-3.
Powerhouse alternative 2-1 is located in an area of overburden which has
been tentatively classified as a glacial moraine deposit. The deposit
is generally covered by a mantle of forest duff and exposures are poor.
Numerous rounded boulders and cobbles are present on the surface and the
slopes are moderately steep and in most areas very uniform. Borings DH
109 and DH 110 indicate that the deposit is coarse-grained consisting of
cobbles and boulders with a sand and silt matrix with some sand layers.
Compressional velocities obtained from the seismic refraction survey are
low indicating a generally loose nature for the deposit. The boring
results indicate that the deposit reaches a maximum thickness in excess
of 100 feet.
The closest outcrop of bedrock ;s along the southern edge of West Creek
and upslope near the western end of seismic refraction traverse SL-1.
The bedrock exposures consist of a slightly-weathered granodiorite with
moderately close to closely-spaced fractures. Bedrock encountered in
the borings consisted primarily of andesite suggesting the probable
presence of a dike swarm beneath this area.
Powerhouse alternative 2-2 is located a short distance east of alterna-
tive 2-1. It is located beyond the area of explorations and on the
floodplain of West Creek and the Taiya River. The floodplain deposits
are anticipated to consist primarily of sand and gravel. Based on a
Converse Consultants, Inc.
-46-
projection of the subsurface information at the alternative 2-1 site,
the bedrock surface is anticipated to continue to slope downward in an
easterly direction. Thus, it is anticipated that the thickness of over-
burden increases toward the alternative 2-2 site.
5.9.3 Powerhouse Alternative 3
Exploration at powerhouse alternative 3 consisted of geologic mapping
and seismic refraction traverse SL-11.
Bedrock consisting of a slightly-weathered, hard granodiorite with
widely-spaced fractures is exposed in the immediate vicinity of the
powerhouse site. Seismic refraction traverse SL-ll indicates that the
bedrock surface dips downward toward the east beneath the Taiya River
Valley. The overburden in the Taiya River Valley is anticipated to be
similar to that present in the vicinity of the other powerhouse sites.
5.10 RESERVOIR
Construction of the West Creek Project will result in the inundation of
the upper West Creek Valley. A reservoir with maximum normal water sur-
face elevation of 700 feet would create a lake approximately two miles
in 1 engt h.
5.10.1 Geology
Geology in the area of the proposed reservoi r was evaluated by the in-
terpretation of aerial photographs, low level reconnaissance by helicop-
ter, and by field checking.
The proposed West Creek reservoir is located within a glacially modified
drainage basin generally characterized by steep valley walls and a flat
valley floor. During the Pleistocene Epoch, glacial ice scoured and
deepened the basin to an elevation well below the present valley level.
During this period, any pre-glacial soil and incompetent zones of bed-
rock were removed. After the retreat of glacial ice, a proglacial lake
Converse Consultants, Inc.
-47 -
was formed behind a rock ridge near the proposed dam site area. Subse-
quently, the lake water topped the natural dam and began erosion of
water channels through the ridge. Evidence observed within the various
swales along the ridge suggest that in past times the impounded water
flowed through various channels at different lake levels. A thick se-
quence of glacially derived sediments were deposited in the lake and
judged from a projection of the valley walls, a thickness of at least
250 to 300 feet of sediments is likely (Callahan, Wayland 1964). It is
anticipated these sediments will consist of bedded silt, sand, rockflour
and clay interbedded with coarser sands and gravels.
Alluvium exposed in the active stream channel and stream cuts in low
terraces consists primarily of sand, and sand and gravel with some silt.
The interpretation of electrical resistivity soundings completed in the
potential borrow area suggests the coarser-grained surface material may
be on the order of 25 feet in thickness.
Glacial materials presently being deposited by alpine glaciers in the
upper valley area consist primarily of heterogeneous deposits of si It,
sand, gravel, cobbles and boulders.
Bedrock is generally exposed on the steep slopes within the reservoi r
area and is anticipated to consist primarily of granodiorite. Numerous
cone-shaped depos its of talus mark the lower portion of the va 11 ey
walls. These deposits consist primarily of rock fragments ranging in
size from sand up to blocks several feet in size.
Converse Consultants, Inc.
-48-
6. ENGINEERING CONSIDERATIONS
The purpose of this investigation has been to acquire, compile and in-
terpret preliminary data for use in the feasibility design study of the
Haines-Skagway Regional Study, West Creek Project.
The subsurface exploration including number, attitude and depth of bor-
ings, amount of seismic refraction surveys and locations and features to
be investigated were determined in consultation with personnel of R. W.
Beck and Associates, Inc.
Conclusions and recommendations developed from this phase II investiga-
tion are presented in the following paragraphs and specifically related
to proposed structure locations and information provided by R. W. Beck
and Associates, Inc., at the time of investigation. Conclusions and
recommendations presented here in are not considered final or adequate
for final design or construction.
6.1 DAM FOUNDATION
The area of the proposed dam site was explored by six borings, DH 102
through DH 107, and seismic refraction traverses SL-6 through SL-I0. In
addition, geologic mapping was completed in the general vicinity. All
of the explorations completed during this phase II investigation indi-
cate that the granodi ori te bedrock wi 11 provi de an adequate foundat ion
for either an embankment dam or a roller-compacted concrete (gravity)
dam.
6.1.1 Bedrock Properties
Limited laboratory tests have been completed to determine the physical
characteristics of the granodiorite bedrock. The results of the rock
tests are shown on Table 6-1. A summary of the computed strength values
are shown on Table 6-2. Rock testing results are presented in Appendix
C.
Converse Consultants, Inc.
TABLE 6-1
ROCK TEST SUMMARY
Young' s ~u I us
Rock(1) Test (2)
psi x 106
Polssoo's(5) Boring Specimen Depth Density Specific Ultimate
Project Feature No. No. (feet) ~ ~ (pet) Gravity Strength Tangent (3) Secant (4) Ratio
Left Abutment 102 102-1 11.0 -11.5 (I) LC 166.1 2.62 16,210 5.02 4.21 0.24
Left Abutment 102 102-2 ;!l.1 -20.5 (I) DEN 167.4 2.63
Left Abutment 102 102-3 41.0 -41.45 AI'{) DEN 161.4 2.53
Left Abutment 102 PET-l02 41.45-41.5 fW PET
Left Abutment 103 PET-103 7.5 -7.6 (I) PET
Left Abutment 103 103-1 7.6 -6.0 (I) DEN 166.4 2.59
Left Abutment 103 103-2 6.0 -6.4 (I) LC 167.6 2.62 ;!l, 320 (6) 5.60 3.98 0.20
Left Abutment 103 103-3 14.3 -14.7 (I) LC 166.1 2.63 4,699
Left Abutment 104 104-1 21.3 -21.7 (I) LC 167.1 2.62 16,350 5.52 4.30 0.25
Left Abutment 104 104-3 25.3 -25.7 (I) DEN 167.2 2.62
Left Abutment 104 104-4 34.7 -35.1 (I) LC 167.7 2.63 15,920 5.98 5.96 0.12
Left Abutment 104 PET-I04-1 35.5 -35.6 N1J PET
Left Abutment 104 PET-l04-2 140.0 -140.5 NIJ PET
Ri ght Abutment 105 105-1 12.7 -13.1 (I) DEN 166.3 2.61
Ri ght Abutment 105 105-2 ;!l.5 -20.9 (I) LC 167.4 2.62 19,920 7.22 4.98 0.27
Right Abutment 105 105-3 ;!l.9 -21.25 (I) LC 167.1 2.62 12,430 6.14 6.06 0.26
Intake Structure 106 106-1 5.7 -6.0 (I) DEN 165.6 2.61
I ntake Structure 106 106-3 14.35-14.6 (I) LC 167.1 2.62 10,090 2.23 2.56 0.17
Right Abutment 107 107-1 46.6 -48.9 NIJ LC 166.0 2.61 ;!l,600 7.63 6.93 0.22
Ri ght Abutment 107 PET-107 46.9 -49.1 NIJ PET
Surge Tank 100 PET-l 00 373.0 -373.1 NIJ PET
FollO<llng data corrpleted by The Robbins Corrpany
Surge Tank 100 3659 63.0 -64.2 (I) LC 2.67 10,190
Surge Tank 106 3659 63.0 -64.2 LC 2.67 12,730
Surge Tank 100 3660 209.2 -210.0 (I) LC 2.67 6,910
Surge Tank 106 3660 209.2 -210.0 (I) LC 2.67 14,010
Surge Tank 100 3660 209.2 -210.0 00 LC 2.67 6,910
Surge Tank 106 3661 375.0 -376.2 NIJ LC 2.4 8,275
Surge Tank 100 3661 375.0 -376.2 NIJ LC 2.4 8,275
Surge Tank 106 3661 375.0 -376.2 NIJ LC 2.4 7,640
Surge Tank 100 3661 375.0 -376.2 NIJ LC 2.4 6,365
Surge Tank 106 3662 466.5 -487.7 (I) LC 2.66 7,640
Surge Tank 100 3662 486.5 -487.7 (I) LC 2.66 12,730
Surge Tank 108 3662 466.5 -487.7 (I) LC 2.66 12,730
Surge Tank 100 3662 486.5 -467.7 (I) LC 2.66 15,260
(1 )Rock Type: 00 = granodiorite; ArJJ = altered granodiorite; At{) = andesite dike.
(2)Test Type: LC = uniaxial unconfined corrpressloo test; DEN = density and specific gravity tests; PET = petrology;>etrographlc analysis
(3)Tangent t'Jodulus based on rrost linear portion of stress-straln curve at 40 percent of the ultimate axial stress.
(4)Secant ~ulus from zero stress to 40 percent of ultimate axial stress.
(5)Poissoo's Ratio calculated fran tangent pcrtlon of axial and radial stress-straln OJrves.
(6)Ultimate strength 10<1 due to fal lure aloog pre-exlstlng fracture, no Young's ~ulus or Poissoo's Ratio calculated.
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Laboratory tests indicate that the rock has good compressive strength
ranging between 10,090 and 20,800 pounds per square inch (psi) and aver-
aging 16,505 psi. That range/average ignores one uncharacteristic low
value.
As noted in Table 6-2, the average elastic modulus of the core tested
was 4.9 million psi with an average value of 5.2 million psi for samples
from the right abutment and 4.6 million psi for the left abutment. The
rock quality designation (RQD), as noted on the boring logs, was re-
viewed to provide a guide as to the degree of natural jointing and frac-
turing of the rock. See Figure A-I, Appendix A, for the explanation of
rock quality designation. The RQD values ranged between 25 and 100 per-
cent. However, the low values are somewhat deceiving. A total of 70
percent of the core recovered had an RQD value of 90 percent or higher.
Range of Compressive
Strength (psi)
Average Compressive
Strength (psi)
Range of Secant
Modulus (psi)
(elastic modulus)
Average Secant
lV10dulus (psi)
(elastic modulus)
Range RQD
*Standard deviation
TABLE 6-2
SUMMARY OF ROCK TEST DATA
All Data Right Abutment Left Abutment
10,090 10,090 15,920
to to to
20,800 20,800 20,320
16,505 15,810 17,200
*S = 3,834 *S = 5,352 *S = 2,088
2.6 x 10 6 2.6 x 10 6 4.0 x 10 6
to to to
6.9 x 10 6 6.9 x 10 6 6.0 x 10 6
4.9 x 10 6 5.2 x 10 6 4.6 x 10 6
S = 1.4 x 10 6 S = 1.9 x 10 6 S = 0.9 x 10 6
25% -100% 25% -100% 31% -100%
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Additional rock property values include an overall mean average of 167.0
pcf (pounds per cubic foot) for granodiorite and 161.4 pcf for a single
andesite sample. The average specific gravity is 2.62 for granodiorite
and 2.53 for the andesite sample. The average Poisson1s Ratio is 0.22.
6.1.2 Foundation Excavation
Bedrock in the damsite area is exposed on the steeper slopes and gen-
erally along the margins of the creek channel. Based on the explora-
tions completed during this phase, overburden thickness on the abutments
ranges from 0 up to about 10 feet.
In the creek bed, bedrock is overlain by recent alluvium. The thickness
of the alluvium is not known, however, it is estimated to have a maximum
depth on the order of 20 feet.
The bedrock is a sl i ghtly weathered to unweathered, hard granodi ori te
with widely-spaced fractures. The borings encountered rock zones which
were closely to extremely closely fractured with some hydrothermal al-
teration. In addition, zones of fractured rock which exhibited slick-
ens i des and/or alterat i on was encountered in bori ngs incl i ned beneath
surface lineaments. This included boring DH 104 which was inclined be-
neath the West Creek channel. Three joint sets were observed. The pri-
mary joint set strikes N700E and dips between 70° to 80° to the south.
Two secondary joint sets had strikes of N300E and N35°W and dip 70° to
75° to the south and approximately vertical, respectively. In the bor-
ings, sound bedrock was encountered below the bedrock surface between
depths of 0 and 5 feet in the ri ght abutment and 5 to 10 feet in the
left abutment. In the area of the left abutment, there may be numerous
large detached blocks of bedrock which have been formed by intersecting
joint sets and the low angle exfoliation or relief joints which are
approximately parallel to the ground surface.
Foundat ion excavat i on requi rements wi 11 vary dependi ng upon the type of
dam selected. During this investigation, consideration was given to an
embankment dam with a concrete face and a concrete gravi ty dam. In the
case of an embankment dam, foundation excavation should consist of the
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removal of all overburden beneath the dam and excavation of all weath-
ered rock in the toe slab area so that the slab will be founded on sound
rock. The shell portion of the embankment can be founded on the exposed
bedrock su rface after overburden remova 1. Some shapi ng of the bedrock
surface may be required.
In the case of a concrete gravity dam, foundation excavation should con-
sist of the removal of all overburden and bedrock down to the sound rock
level. The required rock excavation to reach sound rock for either type
dam is anticipated to average approximately 5 feet on the right abutment
and approximately 8 feet on the left abutment.
Excavation slopes in overburden should be no steeper than 1.5H:1V for
temporary slopes. Overbu rden slopes wh i ch wi 11 be subsequent ly located
below reservoir level should be cut no steeper than 2 1/2H:1V. Excava-
tion slopes in rock will be primarily controlled by joints and permanent
rock slopes should be no steeper than 1/3H:1V. Steeper slopes could un-
dercut the joint planes and may result in unstable slopes or the re-
quirement for rock bolt reinforcement. Temporary slopes in bedrock can
be cut at 0.lH:1V for heights of 10 feet or less. Blast-ing will be re-
quired for rock excavation and specifications should require controlled
blasting to avoid excessive breakage and loosening of foundation rock.
6.1.3 Foundation Treatment
Water pressure tests completed during the subsurface exploration indi-
cate that seepage through joi nts and fractures can occur. For esti-
mating purposes, curtain grouting should be considered and should be
planned to be a single line with holes on 10-foot centers. The maximum
depth of the grout holes would be 75 feet, using the formula H/2 to re-
duce the depth until a minimum depth of 25 feet is reached. For esti-
mating purposes, a grout take of about 0.5 sacks per lineal foot of hole
can be used.
In the case of an embankment dam with a concrete face, estimates should
include consolidation grouting in the area of the toe slab. The toe
slab will be approximately 12 feet in width and therefore, in addition
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to the curtain grout holes, consolidation grouting would require an
additional single line of consolidation holes. These holes would be
staggered with the curtain grout holes to form a triangular pattern on
10-foot spacing. The consolidation holes should be planned for a 20-
foot depth.
In the case of the roller-compacted concrete (gravity) dam, plans should
include consolidation grouting in the highly fractured and/or sheared
rock areas. For planning purposes assume that 50 percent of the foun-
dation area will require consolidation grouting. A triangular pattern
of 20-foot deep hol es on a 10-foot spaci ng, spl it to 5 or closer where
necessary, shoul d be adequate. For estimating purposes, assume a take
of 0.5 sacks per lineal foot of hole.
Although sound rock was judged to occur within 5 to 10 feet of the top
of rock in the cores, it is likely that differential weathering and/or
erosion has occurred along jOints and shear or altered zones, and may
cause the need for dental excavation. For estimating purposes, in areas
where sound rock is required, for example beneath the toe slab or be-
neath the gravity dam, estimates shoul d assume that 10 percent of the
foundation area may require an additional 5 feet of excavation.
6.1.4 Foundation Drainage
It is recommended that foundation drainage be considered in the case
of the concrete gravity dam. Foundation grouting is anticipated to de-
crease the amount of seepage through rock fractu res. However, some
seepage is expected to pass through or around the grout curtai nand
could cause uplift pressure beneath or at the downstream edge of the
dam. A seepage analysis should be performed to determine if a drainage
system is necessary.
6.2 SPILLWAY
Two potential spillway sites have been identified. The initial site is
located in a topographic low on the left abutment and was explored by
boring DH 101 and seismic refraction traverse SL-5. The alternative
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site is located on a topographic bench in the right abutment and was
explored by borings DH 105 through 107 and by seismic refraction tra-
verses SL-7, SL-9 and SL-10.
6.2.1 Foundation Excavation
Bedrock underlies both of the spillway sites at relatively shallow
depths. At the left abutment spillway site, overburden thicknesses are
anticipated to be relatively thin, on the order of a few feet. At the
right abutment spillway site, overburden thicknesses are anticipated to
range between 5 and 10 feet.
Bedrock condi t ions are ant i ci pated to be very si mil a r to those in the
damsite area. The excavation slopes will be primarily controlled by the
joint system. In the left abutment site, the spillway alignment will
parallel the secondary joint set which strikes approximately N300E and
dips 70° to 75° to the south. This relationship results in the left
wall being the most critical. Based on the present information, rock
slopes should be cut no steeper than 1/3H:1V on the left wall and 1/4H:
IV on the right wall. The same rock slopes are recommended for the
right abutment site where again the left wall will be most critical.
Overburden slopes should be cut no steeper than 1 1/2H:1V. It is recom-
mended that a bench be constructed at the overburden-bedrock boundary.
A bench with a width of 20 feet will allow construction equipment to re-
move sloughing overburden material as necessary.
6.3 DIVERSION
There are two likely schemes for dewatering and diversion of West Creek.
One scheme involves diverting the flows through conduits in the channel
while the other scheme involves a cofferdam with diversion through a
tunnel.
6.3.1 Channel Diversion
The diversion of West Creek through the channel would l-ikely consist
of diverting flows around the channel during the low-flow period and
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placing a conduit(s) in the channel bottom. It is anticipated the flows
are relatively low during the winter months. After construction of the
dam, the conduit(s) would be plugged.
6.3.2 Cofferdams
An upstream cofferdam wi 11 be requi red for di vers i on. No subsurface
exploration was completed in this area. Alluvium in the creek channel
at the dam site is judged to be on the order of 20 feet in thickness.
Depending on the location of an upstream cofferdam, the thickness of
alluvium may be greater. The alluvium, based on surface exposures, will
consist primarily of sand, gravel and cobbles. This material is likely
to be highly permeable.
The cofferdam would most likely be an embankment with an impervious cut-
off. Embankment materials could consist of material from road construc-
tion, tunnel muck or sand and gravel located a short distance upstream
in the proposed reservoi r. A suitable source of fine-grained material
has not been located. Alternatives for an impervious cutoff include a
manufactured membrane, slurry trench, or a sheet pile wall.
6.3.3 Diversion Tunnel
Geologically, it appears that a tunnel could be driven in either abut-
ment. Geologic conditions are not expected to differ appreciably from
one abutment to another. However, based on topography, a tunnel in the
ri ght abutment appears more favorable. The steeper topography on the
right abutment would likely result in better portal conditions, more
cover over the tunnel, and possibly a shorter tunnel.
A tunnel dri ven in the ri ght abutment in the vi ci nity of sei smi c re-
fraction traverse SL-7 is anticipated to be primarily in bedrock. A
tunnel located in the left abutment and along the general alignment of
seismic refraction traverse SL-6 will encounter a substantial amount
of overburden along the upstream approximate 200 feet of the alignment.
Downstream from this point overburden is anticipated to be shallow.
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However, the amount of rock cover over a tunnel is anticipated to be
relatively thin and on the order of one tunnel diameter. A tunnel head-
i ng located 200 to 300 feet further upstream will encounter much less
overburden, have a better portal area, and more rock cover. However,
this location will result in a longer tunnel alignment.
Tunneling conditions in rock are expected to be generally good. The
general tunnel alignment will cross the two secondary joint sets at an
oblique angle and be parallel to subparallel to the primary joint set.
For planning purposes, it should be assumed that rock support will be
required along 20 percent of the tunnel length. This support would
consist of 50 feet of light to medium weight steel sets at each portal.
For estimating purposes the steel sets could be approximately 8" x 6-
1/2" WF 24 pounds per foot sets installed on 5-foot centers. The re-
mainder of the tunnel could be reinforced with bolts. These bolts should
be 10 feet in length on 5-foot centers and installed as necessary. In
areas where rock cover is less than two tunnel diameters, additional
support should be estimated. This support should consist of steel sets,
as noted above, installed on 3-to 4-foot centers. In addition, crown
bars grouted ahead of the tunnel face may be required.
In the portal areas, overburden slopes should be planned no steeper than
1-1/2H:1V and rock slopes at 1/3H:1V. For safety purposes, it would be
prudent to plan rock bolts and mesh pinned to rock above the working
portal entrance.
6.4 POWER TUNNEL
Four potential power tunnel alternatives are presently being considered.
These consist of alternatives 1, 2 and 3 located south of West Creek and
alternative 4 located north of West Creek. The major portion of the
field effort was directed towards the southern alternatives. Alterna-
tives 1, 2 and 3 follow the same alignment between the intake and the
surge tank. Between the surge tank and the powerhouse, the alignment
varies depending upon the powerhouse alternative.
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The selected scheme for alternative alignment 1 consists of a combina-
tion tunnel and surface penstock. The tunnel starting at the intake
structure would be approximately 8,470 feet in length and would daylight
on the west wall of the Taiya River Valley upslope of powerhouse alter-
native 1 at approximate elevation 600 feet. A steel surface penstock
would connect the tunnel to the powerhouse.
Other than boring DH 108 drilled at the surge tank location, no other
subsurface exploration, aside from a reconnaissance level geologic tra-
verse, was completed. Recommendations relative to tunneling have been
developed with consideration of boring DH 108, but are also influenced
by the geologic mapping and inspection of aerial photographs.
The power tunnels are anticipated to be driven almost entirely through
bedrock. The exception is the approximate downstream 200 feet of tunnel
alternative 2 which connects to alternative powerhouse 2-2 and will be
located in overburden. This overburden is anticipated to consist of
relatively loose sand, gravel, cobbles and boulders. Bedrock is antici-
pated to consist primarily of granodiorite with occasional andesite
dikes.
For the most part, the rock is anticipated to be relatively massive with
widely-spaced joints. The tunnel will generally be subparallel to the
joint sets. However, at least a portion of each alignment will be par-
allel or near-parallel to one joint set. The major portion of the tun-
nel alignments will cross a series of strong lineaments which appear to
be parallel to some of the joint sets. For a tunnel driven from the
upstream portal these features woul d be fi rst encountered in the ri ght
wall and arch, and would remain in the tunnel until they pass beyond the
left wall. The tunnel alignments will cross at least one inferred fault
zone at approximately right angles. This fault zone is anticipated to
be on the order of 100 to 150 feet in width.
6.4.1 Excavation Characteristics
It is ant i ci pated that the power tunnel coul d be dri ven either by the
drill and shot method, or by a tunnel boring machine (TBM). The gran-
odiorite bedrock is anticipated to be relatively uniform except in the
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areas of faults and beneath the surface lineations. The strength char-
acteristics of sound rock core obtained to date are summarized in Table
6-2. The lineations could represent the locations where mixed face con-
ditions could exist in the tunnel. In addition, it is anticipated that
the tunnel s woul d encounter numerous andes ite di kes. The presence of
the fractured and/or sheared zones coul d effect i vely reduce the hi gh
progress rate anticipated with a tunnel boring machine. Based on exist-
ing data, there is no evidence of broad zones of soft ground or clay
gouge which would cause squeezing in the tunnel. There is no inter-
granular permeability in the granodiorite. However, groundwater may be
encountered in highly fractured and/or sheared zones or faults.
In the conventional drill and shoot method, the rock would not be ex-
pected to present any drilling problems, and an acceptable fragmentation
ca n be ach i eved. The amou nt of su ppo rt neces sa ry will somewhat depend
on the quality of blasting around the periphery of the tunnel. Because
of less disturbance to the surrounding rock, a tunnel driven by a tunnel
boring machine is anticipated to require much less stabilization and
support.
6.4.2 Excavation Stabilization and Support
As previously indicated, it is anticipated that the major portion of the
alignment will be driven in bedrock. The exception to this is the down-
stream few hundred feet of alternative 2 which connects to powerhouse
alternative 2-2. This portion of the tunnel will be driven in over-
burden materials and will require soft ground excavation techniques. The
overburden portion of the tunnel will require the installation of steel
sets capable of supporting the full overburden load. It is anticipated
that the dri vi ng of spi 1 i ng ahead of the tunnel face wi 11 be requi red to
facilitate the installation of the steel sets. It is recommended that
the steel sets be planned for 2-foot centers. Driving of spiling may be
difficult because of the presence of cobbles and nUr.1erous large boul-
ders. Excavation through the overburden can be expected to be tedious
and progress will be slow.
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The bedrock portion of the tunnels will cross several lineaments. These
lineaments are interpreted to be the surface erosional reflection of
highly fractured and/or sheared rock zones. At least one zone has been
tentatively identified as a fault. In the event of construction by the
drill and shoot method, it is judged that approximately 1,000 feet of
highly fractured, sheared, and/or fault zones will requi re support.
This support would be in the form of light-weight steel sets. For esti-
mating purposes, a 5-inch I-beam weighing 10 pounds per foot and in-
stalled on 5-foot centers woul d be adequate. In addition, planni ng
should include 50 feet of the same size steel supports installed on
4-foot centers at each portal. In the remaining approximate 9,000 feet
of tunnel, it is judged that one-half of this length (4,500) will re-
quire reinforcement in the form of rock bolts installed across the
crown. For an 8-foot diameter tunnel, the bolts should be estimated at
6 feet in length, fully encapsulated, and installed on 3-foot centers
across the crown.
If the tunnel is driven by a tunnel boring machine (TBM), less distur-
bance wi 11 be done to the surroundi ng rock and the requi rement for rock
support and reinforcement is judged to be less than that described above
for the drill and shot method. In lieu of the estimated 1,000 feet of
steel-supported tunnel, it is judged that rock control could be achieved
with bolts and mesh installed on a similar pattern as previously indi-
cated for bolted sections of the tunnel. In addition rock bolts should
be planned for an additional 1,000 feet of tunnel to be installed as re-
quired.
Estimates should include shotcrete for sealing areas where spalling is a
problem. It would also be prudent to have provisions for shotcreting
and seal i ng hi ghly fractured and/or sheared zones to prevent or reduce
erosion and plucking of weaker rock by flowing water which could result
in ultimate collapse in the tunnel.
As previ ous 1y i ndi cated, the tunnel schemes -j ncorporate a surge shaft.
In the area of the intersection of the tunnel and surge shaft, rock
support and rei nforcement shou1 d be provi ded. It is judged that thi s
support shoul d be in the form of 6-foot long fully encapsulated rock
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bolts installed on 3-foot centers and medium weight steel sets installed
for a distance of 30 feet either side of the shaft. For estimating pur-
poses, the sets coul d be about 6-i nch by 6-i nch H-beam, 20 pounds/foot
and installed on 4-foot centers.
6.4.3 Lining
Concrete 1 i ni ngs s houl d be provi ded in the soft ground portion of the
power tunnel for powerhouse alternative 2-2 and in areas where the rock
cover, in feet, is less than 0.5 times the head in feet. In addition,
those sections of the tunnel with steel support will require concrete
lining or shotcrete to protect the supports from the flowing water.
A steel-lined section should be provided at the downstream portal and in
areas where rock cover will be less than 50 feet in thickness.
6.4.4 Surface Penstock
A surface penstock coul d be supported by concrete collars and/or pi ers
founded on bedrock. Bedrock is exposed intermittently at the ground
surface in the general area of the proposed alignment. It is antici-
pated that bedrock wi 11 range between a and 15 feet below the ground
surface and will average approximately 5 feet along the alignment. For
p 1 anni ng pu rposes, an average of 5 feet of cover over bedrock can be
used. For planning purposes, it is judged that 2 feet of excavation
into bedrock will provide adequate support. At points where the pen-
stock changes vertical or horizontal alignment, collars or piers can be
anchored to the underlying bedrock.
6.5 INTAKE
An intake structure will be located a short distance upstream of the
proposed dam site, either north or south of West Creek depending on
which power tunnel alternative is selected. There are two alternative
intake designs, one is a free-standing tower with a connecting bridge
while the other would be constructed against a rock slope.
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6.5.1 Foundation Excavation
The intake tower and br)dge supports, if appropriate, should be founded
on rock. At the northside site, bedrock is anticipated to slope steeply
downward and the flatter portion of the site is anticipated to be
underlain by a thick sequence of overburden sediments. Overburden at
the southside site is anticipated to be relatively shallow and underlain
by bedrock.
Excavation slopes in overburden material which will be below the reser-
voir level should be planned no steeper than 2.SH:1V. In addition, it
would be prudent to allow for riprap or concrete lining along the sub-
merged overburden slopes. Overburden slopes which will be above the
reservoir level should be cut no steeper than 1-1/2H:1V. Excavation
slopes in bedrock will be primarily controlled by joint sets. For the
northside site, the left slope is most critical and should be cut no
steeper than 1/3H:1V. The right side and back slope are less critical
and should be cut no steeper than 1/4H:1V. For the southside site, it
should be planned to cut all rock slopes no steeper than 1/4H:1V. In
areas where steeper rock slopes are required, reinforcement by rock
bolts should be planned. Rock bolts 15 feet in length, fully encapsul-
ated and installed on rectangular 8-foot centers should be a basic
pattern. Intersecting joints may require a locally closer spacing.
Careful drilling and blasting will be essential to achieve satisfactory
slopes in rock.
6.6 SURGE SHAFT
As the present time, a 6-foot diameter surge shaft is planned at a point
approxi mately three-quarters of the di stance alol1g the power tunnel.
The subsurface conditions at the site for alternatives 1, 2 and 3 were
explored by the SOO-foot long boring, OH 108. Based on the drilling
information and interpretation of aerial photographs, rock in the shaft
can genera lly be expected to be of good qual i ty, however, it may pene-
trate several fractured, sheared, and/or weathered zones. Some of these
zones are thought to be reflected as nearby topographic surface 1 inea-
ments.
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6.6.1 Excavation Characteristics
It is anticipated that the surge shaft could either be excavated as a
raise by conventional drill and shoot methods or by drilling methods.
If the shaft is excavated by drill and shoot methods, it is anticipated
that some rock reinforcement will be required in the fractured, sheared,
and/or weathered rock lones. Reinforcement consisting of fully encap-
sulated 5-foot long rock bolts installed on 3-foot centers should be
adequate. In addi t i on, shotcrete and mesh may be requi red in areas
where spalling is a problem. For planning purposes, it should be as-
sumed that 15 percent of the excavation will require rock bolts which
woul d i ncl ude an approximate 50-foot sect i on of the shaft at the area
of intersection with the power tunnel. If the shaft is excavated by
raised bore method, it is anticipated that little or no reinforcement
will be required. However, it would be prudent to plan for rock bolting
of the shaft at the intersection with the power tunnel.
6.7 POWERHOUSE
Four alternative powerhouse sites have been defined and consist of Al-
ternatives 1, 2-1, and 2-2 on the south side of West Creek, and Alter-
native 3 on the north side of West Creek. Alternative 1 is located ap-
proximately 1,000 feet south and along the west wall of the Taiya River.
The other alternatives are located adjacent to West Creek. Foundation
conditions vary greatly between the alternatives. Alternatives 1 and 3
will be founded on bedrock. Alternative 2-1 is anticipated to be found-
ed on bedrock, however, extensive overburden excavations are planned.
Alternative 2-2 is located on the West Creek-Taiya River flood plain and
will likely require support by piles driven to bedrock.
6.7.1 Foundations Excavation
Suitab 1 e bedrock is ant i ci pated at the foundation 1 eve 1 s for a 1 terna-
tives 1, 2-1 and 3. Based on completed explorations, granodiorite is
anticipated at alternative sites 1 and 3 and granodiorite with andesite
Converse Consultants, Inc.
-63-
dikes is anticipated at alternative site 2-1. No subsurface explora-
tions were completed in the immediate area of alternative site 2-2, how-
ever, a moderately thick section of overburden materials is anticipated.
Excavations in bedrock will be controlled primarily by joint sets and
rock quality. Excavation slopes in bedrock should be planned no steep-
er than l/3H:IV. Permanent slopes in overburden should be planned no
steeper than 1-1/2H:IV. Temporary slopes in overburden should be planned
no steeper than IH:IV. If temporary slopes as steep as IH:IV are con-
structed, they w"il 1 requi re very close monitori ng by the contractor in
order to detect signs of potential instability.
Excavations located partially or wholly within overburden soils below
the West Creek-Taiya River flood plain surface may require dewater-
ing.
In the case of alternative site 2-2, a steel penstock-power conduit will
be required between the power tunnel and powerhouse. It is recommended
that the penstock be placed on a concrete slab to minimize differential
settlement. The design should take into account the seismic conditions
of the area.
6.8 RESERVOIR
Geologic conditions in the reservoir area were determined by geologic
mapping, aerial overflights and interpretation of aerial photographs.
The flatter portions of the reservoir are underlain by recent alluvium
with bedrock exposed in the steeper portions of the valley walls. De-
posits of talus are accumulating at the base of most of the steep drain-
ages.
No significant areas of landsliding were identified on the aerial photo-
graphs or vi sua lly du ri ng overfl i ghts. However, because of the steep
valley slopes, some slides are likely. Based on available data, it is
doubtful that the slides would be of the size to endanger the project.
Converse Consultants, Inc.
-64-
Avalanches may occur in the project area and specifically in the reser-
voir area. These are anticipated to occur during winter and spring
months when the reservoir surface may be frozen. It is anticipated that
the presence of the frozen surface will minimize the impact of these
avalanches.
Based on available information, reservoir leakage should not be a prob-
lem as long as the project is properly constructed. The rock ridge on
which the dam site is located will act as a suitable barrier to see-
page.
6.9 CONSTRUCTION MATERIALS
An alluvial terrace deposit within the proposed reservoir area was ex-
plored as a potential source of granular construction material. This
terrace area, as shown on Drawing 8, is approximately 1,600 to 4,000
feet upstream of the dam site on the right river bank. Explorations
consisted of test pit excavations, and observation and sampling of
existing cut banks along the river.
The terrace materi al s were predominantly sand with about 30 to 40 per-
cent gravel and occasional cobbles to a maximum size of 4 to 8 inches.
The deposit was relatively clean and particles were rounded. Overburden
to be removed to expose the surface of the terrace deposits was observed
to range from approximately 1/2 to 1-1/2 feet in thickness.
6.9.1 Concrete Aggregate
Laboratory test results for samples of potential concrete aggregate from
the reservoir area are presented in Appendix D and summarized in Table
D-1. The major components of a.ll the samples tested were granitic rocks
and quartz. The constituents were innocuous and free from coatings of
silt, clay, and precipitated mineral matter. The particles are consid-
ered dense and generally sound as indicated by low absorption, specific
gravity greater than 2, and low losses in the chemical soundness tests.
The losses in the L.A. Abrasion tests were relatively high, ranging be-
tween 32 and 52 percent.
Converse Consultants, Inc.
-65-
Based on these preliminary examinations and test results, aggregate
whi ch can be separated from granul ar soi 1 from the upstream terrace
deposits appears to be satisfactory for use as concrete aggregate in
permanent construction.
6.9.2 Embankment Materials
The same terrace materials explored for concrete aggregate appear to be
suitable granular fill materials for the dam embankment. Particles are
sound, rounded, and well graded. Based on the triaxial compression test
and sieve results on scaled specimens as described in Appendix C, the
foll owi ng soil prope rt i es are recommended for pre 1 i mi nary embankment
design assuming the material is compacted to at least 95 percent of its
maximum dry density as defined by ASTM test designation D 2049:
Dry Unit Weight
Moist Unit Weight
Saturated Unit Weight
Effective Angle of Internal Friction
(for confining pressures less
than 12 ks f)
Effective Cohesion
Coefficient of Permeability
125 pcf
136 pcf
142 pcf
41°
o
0.02 to 10 cm/sec
Based on present construction concepts, it is ant i ci pated that a con-
siderable portion of an embankment dam will be constructed utilizing
shot rock. This shot rock is likely to be obtained from required spill-
way and other excavations. As previously described, the bedrock ex-
posed at the surface and encountered in borings consisted primarily of
a slightly-weathered to unweathered granodiorite.
Generally, the rock exhibits widely-spaced joints or fractures but does
have some zones of very closely to closely-spaced fractures. The rock
is relatively isotropic and is anticipated, with proper blasting techni-
ques, to produce approximately equal dimensional blocks. Based on the
Converse Consultants, Inc.
-66-
information available, it is judged that the rock obtained from the
planned excavations will produce a suitable quality rock for use in the
embankment portion of the dam.
6.10 SEISMIC DESIGN
Preliminary seismic design parameters for the West Creek project have
been developed after a review of available tectonic and seismic informa-
tion. As shown on Drawing 10, the project lies within an area consid-
ered to be moderately seismically active. Within a 100-mile radius of
the project site, 128 seismic events were recorded between 1899 and 1980
with magnitudes ranging up to 8.2. Within a 20-mile radius of the
project site, four seismic events have been recorded with magnitudes
ranging between 2.5 and 5.4.
Because of the distance of prior and existing seismograph stations from
the project area and the resulting poor resolution of data, the seis-
micity in the vicinity of the project is anticipated to be higher than
that presented on Drawing 10.
Numerous lineaments have been identified in the field and in litera-
ture for the project area. The lineaments which were field-inspected
suggested that they are the resu lt of different i a 1 eros i on caused by
varying rock quality. A north-trending lineament which crosses all of
the proposed power tunnels has been identified tentatively as a fault.
No geomorphic features have been observed which would indicate
post-Pleistocene movement.
The ATC-3-06 (NSF 78-8) publication indicates the effective peak accel-
eration in the project area is suggested to be approximately 0.35g with
a 10 percent probability of being exceeded in 50 years. The project is
located in seismic zone 2 in the Uniform Building Code and is classified
as a zone where moderate damage could occur. It is recommended that a
peak bedrock acceleration of 0.4g be considered for preliminary design.
Converse Consultants, Inc.
-67-
BIBLIOGRAPHY
American Society for Testing and Materials, 1979, Standard Test Method
for Elastic Moduli of Rock Core Specimens in Uniaxial Compression
ASTM Committee 0-18 on Soil and Rock for Engineering Purposes.
ATWATER, Tanya, 1970, Implications of plate tectonics for the Cenozoic
tectonic evolution of western North America; Geological Society
of America Bulletin, vol. 81, no. 12, pp. 3513-3536.
BAKER, Fred, 1952, The Coast Range batholith between Haines, Alaska, and
Bennett Lake, British Columbia; California Institute of Technol-
ogy M.S. thesis, 45 p.; available from University Microfilms,
Inc., Ann Arbor, Michigan.
BECK, R.l~., and Associates, 1981, Addendum to reconnaissance report on
alternatives for the Haines-Skagway region.
BEIKMAN, H.M., compiler, 1978, Preliminary geologic map of southeast-
ern Alaska; U.S. Geological Survey Miscellaneous Field Studies,
Map MF-673.
BOSTOCK, H.S., 1952, Geology of Northwest Shakwak Valley, Yukon Terri-
tory; Canada Geol. Survey Mem. 267, 54 p.
BREW, O.A., and Morrell, R.P., 1980, Intrusive rocks and plutonic belts
of southeastern Alaska; U.S. Geological Survey Open-File Report
80-78.
BREW, O.A., and Morrell, R.P., 1978, The Wrangell Terrace ("Wrangellis")
in southeastern Alaska; the Tarr Inlet suture zone with its
northern and southern extentions; U.S. Geological Survey Circular
804-B, pp. BI21-BI23.
BREW, O.A., and Ford, A.B., 1978, Megalignment in southeastern Alaska
marks southwest edge of Coast Range batholithic complex; Canadian
Journal of Earth Sciences, vol. 15, pp. 1762-1763.
BREW, D.A., Carlson, C., and Nutt, C.J., 1975, Apparent pre-middle Ter-
tiary right-lateral offset on Excursion Inlet, Glacier Bay Na-
tional Monument; U.S. Geological Survey Circular 733, 59 p.
BREW, O.A., Ford, A.B., 1976, Coast Range megalineament and Clarence
Strait lineament west edge of Coast Range batholithic complex,
southeastern, Alaska.
BREW, D.A., Loney, R.A., and Muffle, L.J.P., 1966, Tectonic history of
southeastern Alaska, in a symposium on the tectonic history and
mineral deposits of the western Cordillera, Vancouver, B.C.,
1964; Canadian Institute Mining and Metallurgy Spec. vol. 8, pp.
149-170.
Converse Consultants, Inc.
-68-
BUDDINGTON, A.F., and Chapin, Theodore, 1929, Geology and mineral de-
posits of southeastern Alaska; U.S. Geological Survey Bulletin
800, 398 p.
CAllAHAN, J.E., and Wayland, R.G., 1965, Geologic reconnaissance of the
West Creek dam site near Skagway, Alaska; U.S. Geological Survey
Bulletin 121-A, 13 p.
Converse Davis Dixon Associates, 1978, Geologic/seismic investigation,
Green lake Hydroelectric Project, Sitka, Alaska.
Converse Ward Davis Dixon, 1980, Final geotechnical investigation Swan
lake Hydroelectric Project, Ketchikan, Alaska, Vol. 1 and Vol. 2.
COBB, Edward H., 1979, Alaskan papers and abstracts compiled by the Geo-
logical Society of America, 1890-1978, indexed by Quadrangles;
U.S. Geological Survey Open-File 79-1640, 201 p.
COULTER, H.W., Hopkins, D.M., Karlstrom, T.N.V., Pewe, T.l., Wahrhaftig,
Clyde, and Williams, J.R., 1965, Map showing extent of glacia-
tions in Alaska; U.S. Geological Survey Miscellaneous Geological
Investigation, Map 1-415.
DECKER, John, 1980, Geologic Map of western Chichagof Island, south-
eastern Alaska; U.S. Geological Society Open-File Report 80-150,
two plates, scale 1:63,360.
DODDS, J.C., March, 1982, Geological Survey of Canada personal communi-
cations.
GABRIEllE, H., March, 1982, Geological Survey of Canada personal commun-
ications.
GRANTZ, Arthur, 1966, Strike-slip faults in Alaska; U.S. Geological
Survey Open-File Report, 82 p.; also, Stanford University Ph.D.
disseration.
HOEK, E., and Bray, J., 1974, Rock slope engineering; The Institute of
Mining and Metallurgy, london.
HYDMAN, D.W., 1972, Petrology of igenous and metamorphic rocks; McGraw-
Hill Book Company, USA.
JACKSON, E.V., 1976, Generalized geologic map of the Canadian Corell-
era; British Columbia Department of Mines and Petroleum Re-
sources, Map A, scale 1:2,500,000.
JAEGER, J.C., and Cook, N.G.W., 1976, Fundamentals of rock mechanics,
second edition, Chapman and Hall, John Wiley & Sons Inc., New
York.
lAHR, John, March 1982, U.S. Geological Survey, personal communica-
tions.
Converse Consultants. Inc.
-69-
LAHR, John, George Plafker, 1980, Holocene Pacific -North American
plate interaction in southern Alaska; Implications for the
Yakataga Seismic ·Gap Geology, vol. 8, pp. 483-486, October 1980.
LATHRAM, E.H., 1964, Apparent right-lateral separation on Strait fault,
southeastern Alaska: Geological Society of America, vol. 75, no.
3, pp. 249-252.
LEMKE, Richard W., and Lynn A. Yehle, 1972, Regional and other general
factors bearing on evaluation of earthquake and other geologic
hazards to coastal communities of southeastern Alaska; U.S. Geo-
logical Survey Open-File 72-516, 99 p.
LEMKE, R.W., and Yehle, L.A., 1972a, Reconnaissance engineering geolo-
gy of the Haines area, Alaska, with emphasis on evaluation of
earthquake and other geologic hazards; U.S. Geological Survey
Open-File Report, 109 p.
LEMKE, Richard W., and Lynn A. Yehle, 1972, Reconnaissance engineering
geology of the Haines Area, Alaska, with emphasis on evaluation
of earthquake and other geologic hazards; U.S Geological Survey
Open-File Report 72-229, 109 p., 4 plates, scale 1:24,000.
MACKEVETT, E.M., Jr., and Robertson, E. C., 1974, Geology of the B-3 and
B-4 quadrangle southeastern Alaska; U.S. Geological Survey Paper
832, vol. 33.
MACKEVETT, E.M., D. Brew, Hawley, C.C., et al, 1971, Mineral resources
of Glacier Bay National Monument, Alaska; U.S. Geological Survey
Professional Paper 632, p. 123.
MILLER, R.D., 1972, Surficial geology of Juneau urban area and V1Clnl-
ty, Alaska, with emphasis on earthquake and other geologic
hazards; U.S. Geological Survey Open-File Report, 108 p.
MILNE, W.G., Rogers, G.C., Riddihough, G.A., McMechan, G.A., and Hydman,
R.D., 1978, Seismicity of western Canada; Canadian Journal of
Earth Sciences, vol. 15, no. 7, pp. 1170-1193.
MULLER, J.E., 1967, Kluang Lake map -area Youkon territory; Geological
Survey of Canada Memoir 340, pp 93-104.
National Geophysics Solar Terrestrial Data Center NOAA, 1981, Source
listings for earthquake information.
PLAFKER, G., March 1982, U.S. Geological Survey, personal communicat-
ions.
PLAFKER, G., Hudson, F., 1980, Regional implications of Upper Triassic
metavolcanic and metasidimentary rocks on the Chi"lkat Peninsula,
southeastern, Alaska; Canadian Journal of Earth Sciences, June
1980, vol. 17, no. 6, pp.81-689.
Converse Consultants, Inc"
-70-
PLAFKER, George, Travis Hudson, and Meyer Rubin, 1975, Southeastern
Alaska, late holocene offset features along the Fairweather
Fault, U.S. Geological Service Circular 733, pp 57-58.
PLAFKER, George, 1967, Geologic map of the Gulf of Alaska Tertiary Prov-
ince, Alaska; U.S. Geological Survey Miscellaneus. Geol. 1nv. Map
1-484
ROGERS, G.C., 1976, A microearthquake survey in northwest British
Columbia and southeast Alaska; Bulletin of the Seismological
Society of America, vol. 66, no. 5, pp. 1643-1655.
SOUTHER, J.G., 1972, Geology and Mineral Deposits of Tulsequah, Map-
Area British Columbia; Geological Survey of Canada, Memoir 362,
pp. 6-38.
TARR, R.S., Martin, L., 1899, Earthquakes at Yakatat Bay, Alaska in
September, 1899, pp 33-45.
T\~ENHOFEL, \~illiam S., and C. L. Sainsbury, 1958, Fault patterns in
southeastern Alaska; Bulletin of the Geological Society of Ameri-
ca, vol. 69, pp. 1431-1442, 1 plate.
WOOD, H.O., and Neumann, Frank, 1931, Modified Mercalli intensity scale
of 1931; Seismological Society American Bulletin, vol. 21, no. 4,
pp. 277-283.
YEHLE, Lynn A., March 1982, U.S. Geological Survey, personal communica-
tions.
YEHLE, Lynn A. and Richard \~. Lemke, 1972, Reconnaissance engineering
geology of the Skagway area, Alaska with emphasis on evaluation
of earthquake and other geologic hazards; U.S Geological Survey
Open-File Report 72-454, 108 p., 4 plates, scale 1:9600.
Converse Consultants, Inc.
/
I--
I
I
I
I
o
I
5 10
I I
SCALE IN MILES
PROJECT LOCATION MAP
Alaska Power Authority Scale NOTED
HAINES-SKAGW A Y REGION FEASIBILITY STUDY Date JAN 1982
WEST CREEK PROJECT
for R.W. Beck and Associates, Inc. Prepared by BH
-----------------------------------------~ Checked by WSB ... Converse Consultants Geotechnical Engineering ~ and Applied Sciences Approved by ALO
CANAJA
PROJECT
Project No.
81-5165
Drawing No.
1
•
4 2 o 4 8 ------Scale in Miles
•
"-"" "7 ;.'
o
.c,
1,
)
/
\
(.)
'0
N o c:
Q) o
(.)
'0
N g
Q)
~
I
(.)
'0
N o
Q)
~
Generalized
>-Geologic
"-Units ~
~ IQul
j{ ITgl
ITk91
Ij §J -, IKurn I ~f
Of
I
itv1zPzv j
I Pzrn I
I Pzv I
~
~
EXPLANATION
Undivided (Quaternary) Glacial, beach, alluvial and talus, unconsolidated, poorly
sorted, sand, silt, gravel and clay. Reworked and glaciomarine drift.
Intrusives (Tertiary) Primarily quartz diorite with subordinate granodiorite and
quartz monzonite.
Intrusives (Tertiary and Cretaceous) Quartz diorite with SUbordinate granodiorite,
quartz monzonite, tonalite, and some migmatic orthogneiss.
Intrusives (Cretaceous) Quartz diorite with subordinate granodiorite.
Intrusive Ultramafics (Cretaceous) Pyroxenite with gradational contact with
host rocks.
Metamorphic Rocks (Mesozoic and Paleozoic) Metamorphosed volcaries to
schistose greenstone and phyllite.
Metamorphic Rocks (Paleozoic) Hornfels, schist, amphibolite; minor marble and
undivided metamorphic rock.
Volcanic Rocks (Paleozoic) Volcanic to metavolcanic, with minor marble.
Undivided Sedimentary Rocks (Paleozoic) Graywacke, chert,
limestone and conglomerate.
Sedimentary Rocks (Paleozoic) Siltstone, mudstone, limestone
conglomerate, and graywacke.
SYMBOLS
- --? -?-Geologic Contact, approximately located, queried where location inferred
---------Limit of geologic information
Normal fault, dashed where inferred
Bedrock lineament, dotted where inferred
REFERENCE: Geology modified from Beikman, USGS Map MF-673, ~Preliminary GeologiC Map of
Southeastern Alaska", 1978; Mackevett and Robertson, USGS Professional Paper
832, no. 33, 1974; Twenhofel and Sainsbury, "Fault Patterns in Southeastern Alaska",
GSA Vol. 69, 1958; Lemke and Yehle, USGS Open File Reports 72-229 and 72-454;
Topography from USGS 1:250,000 SKAGWAY, AK-CANADA Quadrangle.
REGIONAL GEOLOGY
Alaska Power Authority
HAINES-SKAGWA Y REGION FEASIBILITY STUDY
WEST CREEK PROJECT
for R. W. Beck and Associates, Inc.
Scale NOTED
Date JAN 1982
Prepared by BH
Project No.
81-5165
Drawing No.
(i Converse Consultants Geotechnical Engineering
and Applied Sciences
Checked by
Approved by
WSB 2
ALO
KJi
/ Alternative Power Tunnel 4
--------------~ ------~
KJi / ,
;/ )
/
(
/'
./ Ot 1 -
\ .......... -'\-" ..,/ ,-/ '-_.......... tI
~ Alternative
)'
!
/Spilfway
KJi
EXPLANA TION
Oal ALLUVIAL AND GLACIOFLUVIAL: Holocene
deposits of sand and gravel, and probably
underlain by fine sand and silt.
Ot 1 TERRACE: Pleistocene deposits, primarily
sand and gravel.
am GLACIAL MORAINE: Pleistocene deposits
of unsorted silt, sand and gravel with
sub rounded boulders to 3' diameter.
KJi BEDROCK: Jurassic and Cretaceous age
intrusive rocks, primarily granodiorite.
+
Ot 1 ------..........
KJi
SYMBOLS
-
.!~.
"'''~u
.o~
---7-7 Geologic Contact, approximately located,
queried where location inferred
DH-110 Boring location
... SL-6 -t Seismic traverse location
/H Strike and dip of joint
~ Strike of vertical joint
" ~~olnl Summary <showing major joint sets strike V & dip, in addition numerous minor joints and
s irregular fractures exist)
/
KJi
KJi ---...,/
/ \
J \
/
/
/
./ \ ,. a )
",/ t1 / --...---" Oal
}
/
V PowerhouH
-..... ~ Altern.II"e 3
Oal
Powerhou.e Altflrn.".,e 1
400 o 400 s800 \ SCALE IN FEET
REFERENCE: Topography from Tryck Nyman & Hayes,
Anchorage, Alaska, dated June, 1981.
PROJECT GEOLOGY
Alaska Power Authority
HAINES-SKAGWA Y REGION FEASIBILITY STUDY
WEST CREEK PROJECT
for R. W. Beck and Associates, Inc.
Converse Consultants Geotechnical Engineering
and Applied SCiences
N
\
Scale NOTED Project No.
Date JAN 1982 81-5165
Prepared by JM Drawing No.
Checked by WSB 3 Approved by ALO
. . .
£ AJternpwti"
~l11way
, "
. '
LEGEND
-------_ ......
N
s
Normal fault, dashed where inferred
Bedrock lineament, dotted where inferred
Joint Summary, showing strike (direction from north),
and direction of dip
/
Altemotive Power Tunnel 4 /
,
\
s
.. ' .' .
REFERENCE: Topography from Tryck Nyman & Hayes,
Anchorage, Alaska, dated June, 1981 .
PROJECT LINEAMENTS
Alaska Power Authority
HAINES-SKAGWA Y REGION FEASIBILITY STUDY
WEST CREEK PROJECT
Scale NOTED
for R. W. Beck and Associates, Inc.
------------~-----------------------------------------~ch~e~ck-ed7b~Y---W--SB--(i) Converse Consultants ~~~'Z~~I~!~a~~~:~:::ring Approved by ALO
Date JAN 1982
Prepared by JM
Project No.
81-5165
Drawing No.
4
Oal
KJi
\
\
\
\
\
/
/
I
/
/'
Alternative
Intakes
(typica!)
Oal
'-.... -....... -
Po wet Tunnel
Alt<::rnative 4
KJi --.......... -.......-
Qt
KJi
200 o 200
SCALE IN FEET
KJi
EXPLANATION
ALLUVIUM AND GLACIOFLUVIAL: Holocene deposits
of sand and gravel, and probably underlain by fine
sand and silt.
TERRACE: Holocene deposits of sand and gravel,
located above the present river level.
400
Ot 1
KJi
TERRACE: Pleistocene deposits primarily sand and gravel.
BEDROCK: Jurassic or Cretaceous age intrusive rocks
primarily granodiorite.
, __ -.:.KJi
--.0'----'? ..-------
,.t/ 1\0 97 ~{r
SL-5 . ..
SYMBOLS
Geologic Contact, approximately located, queried
where location inferred
Strike and dip of shear zone
Strike and dip of joint
Strike of vertical joint
Boring loca tion
Seismic traverse location
Normal fault, dashed where inferred
_--.••. Bedrock lineament, dotted where inferred
REFERENCE: Topography from Tryck Nyman & Hayes, Anchorage, Alaska, dated June, 1981.
DAM SITE GEOLOGY
Alaska Power Authority
HAINES-SKAGWA Y REGION FEASIBILITY STUDY
WEST CREEK PROJECT
Scale
Date
NOTED Project No.
JAN 1982 81-5165
for R. W. Beck and Associates, Inc.
. (i) Converse Consultants Geotechnical Engineering
and Applied Sciences
Prepared b YBH1 JM Drawing No.
Checked by WSB 5
Approved by ALO
850
1 LEFT ABUTMENT
750
EXISTING GROUND SURFACE
t---j
W
DH-103
W u.
~
z 650 Q
t-« KJi >
UJ
...J
UJ
NOTE: All borings are projected perpendicular to dam axis.
See Drawing 5 for explanation of geologic symbols.
:-850
RIGHT ABUTMENT
-750
DH-105 Approximate Sound Rock Line
Approximate Top of Bedrock
KJi
KJi
SHEAR ZONE
550
._.~~ __ .. L. 450
50 o 50 100
! !
HORI20NTAL SCALE IN FEET
DAM SITE CROSS SECTION
Alaska Power Authority
HAINES-SKAGWA Y REGION FEASIBILITY STUDY
WEST CREEK PROJECT
for R. W. Beck and Associates, Inc.
. (!) Converse Consultants Geotechnical Engineering
and Applied Sciences
Scale NOTED
JAN 1982
Prepared by JM
Checked by WSB
Approved by ALO
Project No.
81-5165
DraWing No.
6
-
Oal
at,
am
KJi
EX PLANA TION
ALLUVIAL AND GLACIOFLUVIAL:
Holocene deposits of sand and
gravel, and probably underlain
by fine sand and silt.
TERRACE: Pleistocene deposits,
primarily sand and gravel.
GLACIAL MORAINE: Pleistocene
deposits of unsorted silt, sand and
gravel with subrounded boulders
to 3' diameter.
BEDROCK: Jurassic and Cretaceous
age intrusive rocks. primarily granodiorite.
/ Power Tunnel
~--_#_ ......
Alternative :3
Qal
SYMBOLS
--?-'?---. Geologic Contact, approximately located.
queried where location inferred
Strike and dip of joint
, Strike of vertical joint
7-1f Strike and dip of shear zone
DH-110 -$-Boring location
_----tt Seismic traverse location
.. SL-1
---•••• Bedrock lineament, dotted where inferred
KJi
KJi
Qal
200 o 200 400
SCALE IN FEET
REFERENCE: Topography from Tryck Nyman & Hayes, Anchorage. Alaska. dated June, 1981.
POWERHOUSE GEOLOGY
Alaska Power Authority
HAINES-SKAGWA Y REGION FEASIBILITY STUDY
WEST CREEK PROJECT
for R. W. Beck and Associates, Inc.
Scale NOTED
Date JAN 1982
Prepared by JM
Project No.
81-5165
Drawing No.
. ~ Converse Consultants Geotechnical Engineering
and Applied Sciences
Checked by
Approved by
WSB 7
ALO
/--' '-/ (
......... ~ ./ /./" ", KJi / \ /1
',-KJi / / , ........ _ /' \ KJi I
......... ---,-----r--./" ----r----.....; Ota )---/
/ I Ota / '" // "'" // I \ Ota ( ,_ / '<...
/ " '----! \"\. I Oal
) --/ _-......../ --... ~-~
"' ------,-------" ---'-~~ ... -~~ ,--~ CIt.... Oal ---~_./--
Ota
Ota
\
'" ""-~ I ,...... / '-KJi --,.-_ I
I ----/
/ --....... / ---/ "-<:
Oal \
Ota
Ota
'" \ ~ a>
'" Cl
Oal
Oal (\ Oal
I \ ---...----.. ..........
(\ / "-//' \
) \ / '......... /--"""'-. /...--\..
Oal
Oal
'-.. c: °i
co
C
o -Q)
05
.r:. o -co
~
,/ \ (................... /' "\. "> Oal __ ./ KJi ../ ,~/ Ota../------.....
(
,,----KJol ~"'-,-{ /" ......
KJi , , ./ " / KJi --~~----....._ ~ '------........... /' \ / ---
\ r --------' \ / -----.._
\ ) KJi \ ---"'\
" ./ KJi "-.......... .........
400 o 400 800
SCALE IN FEET
NOTE: See Drawing 9 for explanation and symbol so
RESERVOIR GEOLOGY
Alaska Power Authority
HAINES-SKAGWA Y REGION FEASIBILITY STUDY
WEST CREEK PROJECT
for R. W. Beck and Associates. Inc.
~ Converse Consultants Geotechnical Engineering
and Applied Sciences
Scale NOTED
Date JAN 1982
Prepared by BH
Checked by WSB
Approved by ALO
Project No~
81-5165
Drawing No~
8
c: 'i
«I ...
C
o -
Oal
Ota
at
Ota
KJi
Ota
Oal
Alternative Power Tunnel 4
/
~
( ~ Alternative
,/\( Spillway
\
\
Oal Oal \
Proposed /Dam Axis
_rnative
.... Intakes --.....--.... Oal TP-5
KJi ......... ___ ~ R-5 • at .C-2 '" \"
-.............. ~ TP-2 ....... Oal """ TP-3 \ '-.,
....... " TP-4. .R-3 R-2· V--11. C-4 I ) EXPLANA TION KJi " R-4 _ '-) J ' " // '-I " " TP~6 Ot.TP-7 / /" ALLUVIAL AND GLACIOFLUVIAL: Holocene deposits
of sand and gravel, probably underlain by fine sand and silt.
TALUS: Holocene deposits of rock fragments ranging from
sand to boulder size.
TERRACE: Holocene deposits of sand and gravel located above
the present river level.
.................. /-'--/ '-R-6 .... R-7 ..//....-----------~
"" / Oal ......... ___ 1-1-(--,...-Y ~~ I " ..... ---......--------""'"'"'----'" --......""-~ --
KJi /
I
KJi
,
KJi
400
/' ---.'
:/
./ y
Power Tunnel
Alternatives 1,2 and 3
o 400 800
SCALE IN FEET
Otl
KJi
TERRACE: Pleistocene deposits primarily sand and gravel.
BEDROCK: Jurassic or Cretaceous age intrusive rocks
primarily granodiorite, I
/ REFERENCE: Topography from Tryck Nyman & Hayes, Anchorage, Alaska, dated June, 1981.
SYMBOLS
,.....-_ ..... Geologic Contact, approximately located, Queried where location inferred
~11. Test pit and resistivity sounding locations and number
C-l Cut Bank location and number
--_ Normal fault, dashed where inferred
--_ ••• Bedrock lineament, dotted where inferred
RESERVOIR GEOLOGY
Alaska Power Authority
HAINES-SKAGWAY REGION FEASIBILITY STUDY
WEST CREEK PROJECT
for R W. Beck and Associates. Inc.
€i Converse Consultants
....... _-..... _---
Geotechnical Engineering
and Applied Sciences
Scale NOTED Project No.
Date JAN 1982 81-5165
Prepared by BH
Checked by WSB 9
Approved by ALO
o 0
o •
o
• AREA OF APPROXIMATELY
40 EVENTS. RANGING
IN MAGNITUDE FROM
2.5 TO 5.4 Oe
~
N
~
17 0 17
SCALE IN MILES
o
34
o
•
•
•
•
• •
•
•
•
\
\
\ " \ "" \ "
o
\ \ , \
\ \
\ \ , \
\ \
\
\
•
\ I ~I
o
\ .... ,.1..
\ '" \ 1'\
\ 1
\ J
\ 1
\ \
\', \ ,
" , ,
\
\
\
\
\
" \ \ , "...: ,~ '\ "., "\ , " \ , ' ..... \\
, ,
\
\
"
•
•
I
\
'\ ,
" ,
SYMBOLS
EARTHQUAKE EPICENTER MAGNITUDES
• 2.5-3.4
o 3.5-4.4
6, 4.5-5.4
o 5.5-6.4
o 6.5-7.4
o 7.5 and Greater
if May be duplicates
Normal fault, dashed where inferred
~ ............... Thrust fault, dashed where inferred,
sawteeth on upper plate
Bedrock lineament, dotted where inferred
FAULTS
~ CD Queen Charlotte -Fairweather Fault
CD Chilkat Fault
\'\
REFERENCE:
\,
\ ' \ '\
\
\
\
0) Shakwak Fault
CD Chatham Strait Fault
CD Lynn Canal Fault
CD Chinakof-Baranof Fault
CD Chichagof-Sitka Fault (Peterson-Slocum Fault)
CD Peril Strait Fault
0) Boundry Fault
® Hubart Fault (Art Lewis Fault)
® Chaix Hills Fault
® Coal Glacier Fault
® Chugah-St. Elias Fault
® King Salmon Fault
® Nahlin Fault
® Gastineau Fault
Earthquake epicenters and magnitudes modified from:
NOAA August 1981, and Canadian Earth Physics Branch October 1981
computer data sheets.
Faults and lineaments modified from:
Beikman, 'Preliminary Geologic Map of Southeastern Alaskan, USGS
MF-673, 1978; Twennofel and Sainsbury "Fault Patterns in
Southeastern Alaska", GSA Bulletin, Volume 69, 1958; E.V. Jackson,
"Generalized Geologic Map of the Canadian Cordilleran, British Columbia
Department of Mines and Petroleum Resources, 1975. \ '. \ '\
"'" ____ .:;E;.:;A~R!.:T~H.:.:Q;:U:::A::::K~F;;..;;E;;;;P~I C~E:;.:N~T~E:;.:R:.!...!&~F:;:A~U=L.:.T..:;M~A~P~ ___ _
Alaska Power Authority Scale NOTED Project No.
t
HAINES-SKAGWA Y REGION FEASIBILITY STUDY
WEST CREEK PROJECT
for R. W. Beck and Associates, Inc.
~ Converse Consultants Geotechnical Engineering
and Applied Sciences
Date JAN 1982 81-5165
Prepared by JM Drawing No.
Checked by WSB 10
Approved by ALO
APPENDIX A
DRILLING EQUIPMENT AND PROCEDURES
A.1 GENERAL
The phase II geotechnical investigation which included drilling, test
pits, seismic refraction traverses, and resistivity soundings was per-
formed between late summer and early winter of 1981 at the proposed West
Creek dam site and appurtenant areas. Table A-I lists all borings in-
cluding location, feature investigated, and length.
TABLE A-I
SUMMARY OF EXPLORATION
Boring No. Feature Depth of Hole, feet
DH 101 Spillway 100.5
DH 102 Left Dam Abutment 99.8
DH 103 Left Dam Abutment 100.9
DH 104 Left Dam Abutment and
Stream Channel 201.5
DH 105 Right Dam Abutment 100.8
DH 106 Right Dam Abutment 75.2
DH 107 Right Dam Abutment 101.0
DH 108 Su rge Tank 502.2
DH 109 Powerhouse Alternative No. 2 141.4
DH 110 Powerhouse Alternative No. 2 98.0
DH 111 Powerhouse Alternative No. 1 50.5
DH 112 Powerhouse Alternative No. 1 75.5
The locations of the above borings are shown on Drawings 3, 4 and 7.
Converse Consultants, Inc.
A-2
The major portion of the explorations were completed in late summer and
early fall. A total of ten borings, DH 101 through DH 110, were com-
p 1 eted by Wyman Construct ion Company of Ketchi kan, Alaska between Sep-
tember 23 and October 22, 1981. These ten borings represent an aggre-
gate of 1,521.3 lineal feet of drilling. Work days ranged from 8 to 12
hours, seven days a week. To expedite the drilling operations two 12-
hour shifts per day were employed in the latter part of October. Temsco
Helicopters Inc. of Ketchikan, Alaska was contracted to provide helicop-
ter support to move men and equipment. A Bell 204 helcopter was used to
move the drill equipment, and a Hughes 500 D Model Helicopter was used
to transport drill crews and geologist as required. These borings were
drilled utilizing a skid mounted Longyear Model 38 diamond drill utiliz-
i ng dual Bean Royal pumps for water supply system.
A small exploration program was completed in early winter and consisted
primarily of the drilling of two borings, DH 111 and DH 112, at the
alternative 1 powerhouse site. This phase of drilling was completed by
Alaskan Enterprises of Juneau, Alaska, between December 2 and 12, 1981.
A total of 126.0 linear feet was drilled during this period. Due to
col d weather and short daylight hours, work days consisted of 6-to
10-hour shifts, seven days a week. Livingston Helicopter Services of
Juneau, Alaska, was contracted to provide helicopter support to move
drill equipment. An Allouette II helicopter was utilized in moving
drill equipment for boring DH 112. Drilling equipment for this program
consisted of a Hydro Wink portable diamond drill, supported by two Bean
Royal pumps for water supply system.
Soil and overburden materials were continuously logged and classified in
accordance with the Unified Soil Classification System in accordance
with terms presented in Table A-2 and bedrock materials were described
in accordance with terms presented in Table A-3. Location and eleva-
t ions of the bori ngs DH 101 through DH 108 were estab 1 i shed by Tryck,
Nyman & Hayes of Anchorage, Alaska. The locations and elevations for
borings DH 109 through DH 112 were approximated in the field by compass
bearing, tape measure and hand level surveys to known survey points.
Converse Consultants, Inc.
A-3
A.2 SAMPLING
Overburden sampling was restricted to materials recovered by the core
barrel and by wash cuttings in the water return. No attempts were made
to sample overburden materials due to the limited thickness and/or the
coarseness.
Bedrock was sampled by continuous core drilling using a 10-foot long NX
2-15/16-inch 0.0. (1-7/S-inch 1.0.) double barrel, wireline core sampler
in borings OH 101 through OH IDS and OH 110. Boring OH 109 utilized a
10-foot long BX 2-5/S-inch 0.0. (1-7/16-inch 1.0.) double barrel, wire-
line core sampler.
2-15/16-inch 0.0.
sampler.
Borings OH 111 and OH 112 utilized a 5-foot long NX
(1-7/S-inch 1.0.) double barrel, wireline core
Core samples were placed in 5-foot long wooden core boxes, photo-
graphed, and placed in storage at the sewage treatment facility in Skag-
way, Alaska. Core recovery and rock quality designation (RQO) were
determined as illustrated on Figure A-I and are recorded on the boring
logs.
A.3 WATER PRESSURE TESTS AND PROCEDURES
Water pressure tests were performed in borings OH 101 through OH 107 at
the dam site and boring OH lOS at the surge tank location to determine
the approximate permeability of the bedrock. Longyear wireline single
pneumatic packer system was used to test all bori ngs. In addition, a
Longyear wireline dual pneumatic packer system was used to test selected
intervals in boring DH 104.
A calibrated flowmeter and a watch with a second hand was used to moni-
tor the rate of flow per unit time within each interval. Where water
was not readily available, a dual pumping setup was utilized. The gen-
eral test procedures are as follows:
Converse Consultants, Inc.
A-4
1. The flowmeter was calibrated using a five gallon container
marked in I-gallon intervals. Actual flow versus measured
flow was calculated and a correction factor established.
2. The drill hole was flushed after drilling and prior to inser-
tion of the packer pressure testing apparatus.
3. A single pneumatic packer unit consisting of a 4-foot long
rubber section was lowered on a wireline through the drill
rods seating in the core barrel and outside the diamond bit.
The dual pneumat ic packer uni t cons i sted of 15 feet of per-
forated pipe separating the 2-foot long rubber lower pack-
er. A compressed air tank was used to maintain a pressure of
250 to 350 psi within the packer system to keep it fi rmly
seated against the drill hole wall and the core barrel.
4. The depth of the test interval for each test was established
and noted.
5. The height of the rods above the ground was measured to es-
tablish the total static head. Water was then pumped into
the hole. Various pressure increments were used based on
possible future hydrostatic load. Generally, holes were
tested at pressure increments of 15, 30,
psi as indicated on the pressure guage.
sure attained was in boring OH 108 where
sure was used.
45, 60, 75, and 30
Maximum water pres-
150 psi water pres-
6. Water fl ow at each pressu re was monitored using a flowmeter
calibrated to 1/10 of a gallon. Constant flow was estab-
lished at each pressure interval.
7. The packer was deflated and moved up to the next test inter-
val.
The resul ts of the water pressure tests are summa r; zed and presented
immediately following the corresponding drill log.
Converse Consultants. Inc.
TABLE A-2
KEY TO SOIL SYMBOLS AND TERMS
TUMS USED IN THIS REPORT FOR DESCRl8lN' SOILS ACCOROIN' TO THEIR TUTURE OR GIlA .. SIZE
DISTRIBUTIONS ARE '£NERALLY 1M ACCORDANCE WITH THE U~IFlED SOIL CLASSIFICATION SYSTEM.
MAJOR DIVISIONS s'~~~is TVP I CAL NAMES TEllIS ~SCRIBIh6 CIXIDITION, CONSISTENCY AND HARlllESS
'ii 0 .. • ..
'" .. ,.
'" .. ...
0 ...
• .. ......
• 0 ... ..
-"7' .... .... ~ -.. .. ... . .... ... .. ... • ... ..
0 .. -'" -....
" • !'
N g ..
• .. • .. .. • -
i .. • ..
'" .. ,. ... · -...
0 .. · ... · -...
• e ... -.. .. .. -. -.. .. e .. ..
~!. · .. ... .. :r .. ..
• !' ..
8 ..
• c • -
'ii -;:: -Gil 0 .. ... ~~ -. .. • • ..... .. ..... 0 " ... .. .. ,. .. ,. .. .. '" 0 .. liP "' .. c .. -:!!. ,. ... .. " .. .0 .. • 0'" • .. .. -... .
_0 -,. .. .. .. ... ..
!:.~ ... • '" ... c •• •• • .. ---~ ;; ... ... .. .. .... -CI' • -.. ,.--..... • • .. .-.. '" _0 _.
liC " ! ~
;: '" " .. • .. ..
'ii ,..
0 .. SM .. ~~ ...
I .. • • .. -... 0 .. -.. ... ... .. .. ,. • ... • .. 5' ... .. ... -! .. ....
:0 ..
0 ... • ...... .. • :0 · " .. . .. ,. ... ... .. . .. .. .. $II .... ... .. -. •• .. • .... c ... -. ... ... .. • _fI' .. .... :0 -:r _ .. • • .. -.. ~ eo -. -:II I :0 se
;: c : .. ..
~ ilL ...
~ .. ~ -!. ::
eL .. ..
:0 .. : ~ .. • .. ... ': .. Ol ,. ... e.
,.. • IIH
5-... -~
!. ;: .. .. .. CH .. ,. .. .. • .. ~ .. • · ... .. .. .. OK ... .. ,. ...
S .. 0 ! ~ ... Pt .. ... ;: .. :r
:!. .; ...
lI.n-, •• d.d , .... ls, , .... 1.
s.nd .lltur,s, llttl, or no
flus
Poo.ll-, •• ded g ..... 1 s,
, .... I-ulld .Ixtu.es,
llttl. 0' no fl •••
!: W .,~::~!:, , .... I-und·
CI.l" , .... Is,
chl .htuns
, •••• l-und-
lIen-,r.dld undl. ,r ... II,
I ... ds, Iitti. or 110 fl •• s
'oorlf-,'.ded I&Rdl,
, •••• I, IlIIdl, little
or no fin ..
Silt, "ndl, .. nd-Illt
.htu •• 1
Cla", undl, nlld·ch,
.txt ••• s
Inol',.lIlc Illtl .n' ... ,
fin. undl •• ock flou.,
I t1 tf or c lafl' fin. u .. dl •
01' c ."1 Ii ts with 11I,ht
plasUcit,
IlIo.,.nic cl',1 of low to
.. diu. plastlclt,. ,ru.ll,
CII,I. I.nd, cl.,I. Illtl
c")'I. I.u .hl'
O'YIIIIC silts .nd o.,.lIle
II tl cla,l of lOll
plastlclt,
!~o~m!:.:!!~:· ,1::·::::;
0' slit, soils •• hUlc
lilts
Inol',.nlc c1&11
,Iutlcit,. fat
of hl,h
ch,s
Or,.nic ch,s of .. dlull to
hl,h phstlclt,. or,.lIlc
silts
Put nd other hlghl,
or,.nlc soils
COARSE &RAJ.ED SOilS ( •• Jor po.tlon reUlud Oft .0. 20011"'1'
Includ.s (1) cl •• n , ••• els, (2) silt, or cl.,., ,r •• els ••• d 3)
slltl, eI.,el 0' , ... ell, s .. ds. Consist,nc, Is r.ted eccordlft,
to .elatln densit,. as dete •• lned bl labor.to'l tests •
OISC.lethe Te •• ttel.t" • o.n, itZ
Ve., loose 0 to 151
loose 15 to 401
Medlua d •• se 40 to 70S
Gense 10 to 151
Varl d.nll 85 to IDOl
FIIIE &RAIIIED SOILS (aajo. portion pUlh, 110. ZOO sl ... ), IlIch ....
(I) IlIor,anlc aftd o',lIIlc lilts and cl'IS. (2) ,r .. ell" sud, er
silt, CI.,I, .nd (3) cl"'l 111tl. Consilt'"CI Is r.t.d .ccordl.,
to ,hu.ln, stran,tII. " IlIdlcated 1>1 p .... t'o .. t.r '''~I.,s Or b,
dlrlct sh •• r t'lts.
D .. crl!tI~. T.r. ~1I1!r St.lft.th Iklfl
Ver, soft
Soft
Fl ••
StIff
Ve., It Iff
H •••
Dllcrtet he T.ra
Soft
IIod •• atel,
1I •• d
H •• d
V'rl lIa.d
Ie .. t .... 0.21
0.25 to 0.50
0.50 to 1.00
1.00 to 2.00
2.00 to 4.00
4.00 'II~ .. I' ....
Field I~elltiflcttl •• TeU
en •• ,u, " h .... ~ crull •• b, fl.,er,
Frlabl., cu •• "' ....... ,1,
wlU hit ...... will c ..... l.
ra.dl1, u.der 1I,IIt 11._.
bloll'
k .. lf. lel'.tcll 1.u., .ust
tr.u, 11111 IIltht .... fft
"'_r 1110111 Nfol'l •••• th,
Ser.te .... wit .. tRlfe .. It ..
difficult,. dlfflult t. bl'''. lilt .. 1I __ r 111011'
SOl L II)ISTURE
Fro. 1011 to hl,h the .011 .. lItul" II Indicat .. b"
Or,
Dnltnlt loll
Trice
little
So..
Aftd
GRAUl SIZE DISTRIBUTI~
S1t,lItll Milt
1I0ht
V"l ... ilt
M.t
S 12£ PfOIORTIIIIS
P,re ... t br "eltltt
o to 10
10 to 20
20 to 3S
35 to 50
I-Wy-........ ......---:SILT---O·""~--flM:-_-_--4-.;I ..... SNtO_~-~-_-... ·~~--~_--ooj.I ... -~:--a_-.. -Il------ooj-ooj:1
SIll'! SIll _I 2111 1III 140 1111 III 40 20 It • Ii' !I' I' Iii' r r
I .~. --~~~Jn~~T..DII------~-,.r-~Or.I--------~.5.-~I~.O--~----~"~-~ ••• ------~~ .. t.r ..
.. 1,,",eLa Dt ..... IET ... tN MILLIMI:TIUtS
HARDNESS
TABLE A-3
EXPLANATION OF BEDROCK TERMS AND SYMBOLS
SOFT
MODERATELY
HARD
HARD
VERY HARD
-Can be dug by hand and ctushed by fingers
-Friable, can be gouged deeply with knife and
will crumble readily under light hammer blows
-Knife scratch leaves dust trace, will with-
stand a few hammer blows before breaking
-Scratched with knife with difficulty, dif-
ficult to br.eak with hammer blows
THINLY LAMINATED
LAMINATED
-less than 1/10"
-1/10" to 1/2"
STRATIFICATION VERY THINLY BEDDED -1/2" to 211
FRACTURING
WEATHER:[ NG
JOINT ATTITUDE
THINLY BEDDED _211 to 2 feet
THICKLY BEDDED -more than 2 feet
INTENSELY FRACTURED -less than 111 spacing
VERY FRACTURED -1" to 6 11 spacing
MODERATELY FRACTURED -6" to 12" spacing
SLIGHTLY FRACTURED -1211 to 36" spacing
VERY
WEATHERED
MODERATEL Y
WEATHERED
SLIGHTLY
WEATHERED
FRESH
N20W -
•
50N
-Abundant fractures coated with oxides, car-
bonates, sulphates, mud, etc., through
discoloration, rock disintegration, mineral
decomposition
-Some fracture coating, moderate or local-
ized discoloration, little to no affect on
cementation, slight mineral decomposition
-A few stained fractures, slight discoloration,
little to no affect on cementation, no mineral
decomposition
-Unaffected by weathering agents, no appre-
ciable change with depth
Strike (in degrees)
Dip (in degrees)
Vertical Joint
CORE
RECOVERY
10"
2"
2"
3"
4"
5"
3"
4"
6"
4"
2"
5"
50"
Core Recov.
=51)/60 = 33%
~ : ....
~ a :
~ ::.
:.-.
r:8 ..
fQ
" "-1:/ , ... .,
[J , ....
" .
. ~~ •. : [J ".; .. -
BJ ..
Cl , "
" ,
LJ ' "
' .. . . '
,'.
o. "
c~~
;"0
C3
[0J
lU ' , .....
~;.
Core
Run
60"
t1001 FI EO
CORE RECOVERY
(Pieces in excess of 4" in
10"
4"
5 11
4"
6"
5 11
34"
RQO
= 34/60 = 57%
ILLUSTRATION OF CORE RECOVERY & RQD
Alaska Power Authority
wEST CREEK PROJECT
for R.W. 8eck and Associates, Inc.
@ Converse Consu Ita nts ::.f~:~,~~~.~~:~~::"ng
length)
Project No
81-5165
Figure No
A-1
RWB-487B DRILL HOLE LOG Hole No. _ ...... Du.Hl......Il.J.jO""'J __ _
Project Hal nes-Skagway HydroeJ eetri c Project Feature __ S::.jpu..1L·lLJ.uW/JI..Ja:1:y~ ______ Bearing !)I401~
Coordinates -.IN.l..I2-..;8,L,11u5,u2..:4I..12.y;_...JE ... 2...,3.!.!6J...l.&..l8./.l3",5~ _______ Ground Elevation 777 A 60 0 • Angle with Horizontal--lo_Ll._I...-__
Type of Hole __ N_x_W_i_r_e_l_i_n_e_ Total Depth_----:1:....:0 ..... 0_._5 ___ Start_-:....:;;.9.!-/.=.23~/ ..... 8:....:1;;....... __ Finish 9/24/81
Water Level -Depth, Elevation, Date ___ ....:.n....:.o....:.n....:.e~ ___________ Logged By __ ..... C"'--PL..-B~e .... nU.S0l20I.Lnl..1..-__ _
Drilling Co.
Angle Depth
Elevation
&: Size Hole,
Box No.
1-....-
-
-
Wyman Construction Driller Sutch Umghr:l
%
Rec.
RQD
I
Classification and Physical Condition
BEDROCK ( a . 5 -100. 5 )
I Water
; Pressure
Test
Interval
Granodiorite,light gray, speckled blac~,
med. grained, hard, slightly weathered
to 7.5' grades to unweathered below;
very widely fractured, with apparent
dips of 45-600 , planar, v. narrow, in
fillings of pyrite, iron stained with
alteration halos to 0.1' thick.
10-100
......
x o co
N
x o co
-
--
IS--
-
-
-
-
-
--
-
35--
-
-
i-J--
I1n
26.5, fracture, glanar, slightly rough,
v. narrow, at 45 , infilled with
cal cite.
32.1-32.3, fracture, planar, slightly
rough, v. narrow, at 45 , alteration
halo 0.1' thick, clean.
33.8-34.5, zone of alteration around
0.1' wide around fracture, planar,
slightly rough, v. narrow, at 45-500
Converse Consultants
Sheet of :i
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc. )
drilled to NW casing
to 2.4, 3.5" d i a .
hole, drilled with Nx
standard core to 8.5,
3. 0" d i a. ho 1 e .
drilled with Nx Wire-
line core to 100.5,
3.0" dia. hole.
100% water return
throughout drilling.
Note: only natural
fractures are des-
cribed, many fracture~
are drilling induced.
RWB-487B DRILL HOLE LOG Hoi e No. _-.u.Du.I-l-.!.Jl O.J...J.I.--__
Project Haines-Skagway Hydroelectric Project Feature ___ S.l.fp..L1L.' ]L.]J-,;w""a""yf--___ Sheet_~ __ of 3
ARgie Depth
Elevation
& Size Hole,
Box No.
x o co
-
-
45-
-
-
-
-
55 I I
-
60-
-
%
Rec.
RQD
-100
I-r-
x o co
-98
-
65-
-
-
-
75 -
-
-
-
-
-
I 85
-
Classification and Physical Condition
Granodiorite (cont1d)
39.5-39.8, fractures, P6anar, slightly
rough, v. narrow, at 45 , with an alter
ation halo.
41.0, fracture, 8lanar, slightly rough,
v. narrow, at 45 , with an alteration
halo.
74.7, fracture, 8lanar, slightly rough,
v. narrow, at 45 , with a ~" alteration
halo.
76.4, alteratisn halo along rehealed
fracture at 50 .
quartz band at 50 0 , ~" wide.
Converse Consultants
Water
Pressure
Test
Interval
N
+oJ
til
Q)
I-
-..-
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc.)
RWB-487B DRILL HOLE LOG DH 101 Hole No. _______ _
Project Hai nes-Skagway Hydroe' ectri c ProjeCy..eature __ S_P;....'_·l_'_w_a-..::y ____ Sheet __ 3 __ of __ 3 __
I t\A!!e Depth "" Water Remarks
Elevation % :<:'>1) Pressure (Water Loss and Color, Casing
i & Size Hole, Rec. 0.0 Classification and Physical Condition Test Record, Time of Drilling, etc.)
RQD ;::....1 Box No. 0 Interval
\ .... \ ~I
(cant'd) -I I Granadi ar; te -I~,,--\
... \ I \ -",_,
;'\-;,--I~ri~: " ......... ' -• I" , .... I,
90--
0"-./ .... -_,,-,I ',I ."
L.("') -1.1' ~I
'" 1/, 1
X 100 .1_~_,1 ......
i
0 -_ ;'1\"
cc . )C' ;. ,;', ....., :+ -10 1'1".,1_ N In
,_/. ,I <IJ -,-''''' ....., I-
,-I~~' In
95--<IJ , ~'I", l-
I , ..... J
-)1 :-J~
;':' !... \,Q -V~' ,\
X \I,i~
0 " ",,-, cc 100 I "" \ I ~ -'-'-./ 100--100 -:,"\
-Bottom of bonng at depth 100.5
-
-
-
-
-
-
-
-
-
-
-
-
-,
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
I
Converse Consultants
RWB
SD-88
R. W. Beck and Associates
DRILL HOLE WATER TESTING Hole No. DH 101
Project Ha i nes-Skagway Hydroe 1 ectri c Feature ~_--"4''-LL..Ln\,,+-________ Sheet ----L-_~ of _..1.--_
Depth to Water Table __ d_r,,-y __ Height of Swivel above Ground see remarks Size of Hole Nx Wi re 1 i ne, 3.0" di
Test Equipment Wi re 1 i ne Packer Drill Foreman B. Umphreys Inspector CPB
Time Period Depth (Feet) Loss Pressure Date of Test Top of Oep-th Remarks
Begin End (Min.) Packer of Gallons GPM (psi)
Boring
August 15:00 15:05 5 63.0 100.5 3.2 0.64 15 Single pneumatic
24/1981 15:07 15:12 5 4.55 0.91 30 Packer used
15: 14 15:19 5 5.7 1.14 45 Top of Water
Test 15:23 15:28 5 6.95 1.40 60 Swivel at 3.5 ft. above
1 15:30 15:35 5 4.0 0.80 45 ground surface
15:40 15:45 5 2.9 0.58 30
15:47 15:52 5 1.8 0.36 15
Test 16:00 16:05 5 23.0 100.5 4.6 0.92 15 Top of water
2 16:06 16: 11 5 6.3 1.26 30 Swivel at 3.5 ft. above
16: 12 16:17 5 3.5 0.70 15 ground surface
I I
t-
lJ.J
lJ.J
l..L..
z:: o
I-i
t-
<::(
:>
lJ.J
....J
lJ.J
800
780
760
740
720
700
680
Ground Surface
DH-101 Z Overbur _d.-e_n __
BEDROCK: Granodiorite unweathere ,
very widely fractured, alteration
halo·s around some fractures
2
wATER PRESSURE TEST
1 1.40 gpm at 60 ~si
2 1.26 gpm at 30 psi
"""---Total Depth 100.5 1
SUMMARY LOG DH-1 0 1
Alaska Power Authority
WEST CREEK PROJECT
for K.\~. Beck and Associates, Inc .
. ~----
SPILLWAY
Project No.
81-5165
i) Converse Consultants A-1
RWB·487B DRILL HOLE LOG Hole No. DH] 02
Project Haines-Skagway Hydroelectric Project Feature Left abutment North Bearing ____ _
Coordinates _...!.N.:.::2:.::8::..:1::...4:..::6:.::3:..c7-",--..!::E:.!::2:.!::3:.:::6:..=1..:;9-=1~5 _______ Grou nd Elevation 662 . 7 60 0 Angle with Horizontal -.l._l..I._'--__
Type of Hole _N_x_W_,_' r_e=-.l=-.i_n....:e:...-_ Total Depth _--.:9:....:9....:.:....:8=--___ Start 9/27/81 Finish 9/29/81
Water Level Depth, Elevation, Date ___ A_t--.,;:;g_r_o_u_n_d_s_u_rf_a_c_e ______ Logged By ---lC,....../:P~B~e~nI.:i5>s;;O~n>-----
Drilling Co. WYman Construction Driller Butch UmQhrJ!
Angle Depth
Elevation
& Size Hole,
Box No.
%
Rec.
RQD
Classification and Physical Condition
Water
Pressure
Test
Interval
_ Forest Duff, dark brown' wet,soft.
COLLUVIAL SOIL
-(1.0-4.6)
-Gravelly sand, brown, fine to medium,
-~ __ ~ __ ~l~ii~ttlule~~s;~i·lut~·-m~oli~is~t~m~e.~rll~iiw'llm~~rlp~nl~~:p~ __ ~
10-
-_100
_ 1QO
-
BEDROCK
(4.6-10.0)
Granodiorite, gray, speckled black, me(.
grained, med. hard, slightly weathered
megium fractured, with apparent dip of
50 , planar, rough, narrow, infilled
with iron oxide.
~ 15-
10.0-39.4, grades to hard, unweathered
wigely fra8tured, with apparent dips 0
50 -90, planar, rough, v. narrow,
infilled with iron oxide and chlorite.
with alteration halos around some
fractures.
co --
-
-
-
-
30-
-
-100
N -89
-
-
40
N
+oJ
34.4, fracture, planar, slightly rough, ~
infilled with chlorite, ~" alteration I-
halo.
37.9-d8.9, rehealed fractures, at
80-90 , infilled with chlorite.
(continued)
Converse Consultants
Sheet o 3
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc.)
dri 11 ed with NW
casing to 7.5, 3.5 11
dia. hole.
drilled with Nx Wire-
line core without
inner tube to 9.6,
3.0" dia. hole
Many fractures drill-
ing induced from 4.6
-.to 9.6
I~Sample 10.75-11.61
drilled with Nx w;re-
line core to 99.8,
3.0" dia. hole.
(Sample 20.0-21.251
100% water return
throughout drilling.
RWB-487B DRILL HOLE LOG Hole No. _=-:DH:..:.....;1::.,:0:..:2=----__
Project Haines-Skagway Hydroe 1 ectri c Project Feature_--=l-=e...:..f..::t-=.a.::.b.::.u.::;tm:.:.:.e=-:n:.;,.t=--_ Sheet _-=2,--_of _....::::3 __
Angle Depth
Elevation
& Size Hole,
Box No.
-
I-~
-
-
-
50-
-
('V) 55-
x o co
I-I--
<::t"
X o co
-
-
-
60-
-
-
65-
-
-
-
70-
-
-
75-
-
-
-
80 -
-
85
%
Rec.
RQD
Classification and Physical Condition
ANDESITE DI KE
(44.5-99.8)
gray, speckled black, med. grained, un-
weathered; wid31y fra8tured with appar-
ent dips of 45 to 60 ; planar, sl.
rough, v. narrow, infilled with clay
and chlorite, numerous rehealed 6ract-
ures with apparent dips of 45-70 .
o 58.1-58.5, rehealed fracture. at 70 ,
infilled with chlorite.
Converse Consultants
Water
Pressure
Test
Interval
T
i _
!
I
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc.)
~ample 40.75-41.751
RWB-487B DRILL HOLE LOG DH 102 Hole ~o. ______ _
Project Hai nes-Skagway Hydroel ectri c ProjecWeature_~L=-e=-f_t::.-..:.a:-=b:....:u::..;t:....:m...;e:...n:....:t __ Sheet __ 3 __ of __ 3=--_
AAgie Depth
Elevation
& Size Hole,
Box No.
-
-
-
-
90-
-
-
-
-
L..n 95.--
x -0
c::l -
-
100 --
95
100
100
Classification and Physical Condition
Water Pressure Test Interval
~J \..'~ -I" "'~~/~ 'I,,,
Granodiorite (cont'd)
86.4, rehealed fracture at 50 0 , infille~
\\~'\" with chlorite. 0 ,S .... ; ~~ . 87.9, rehea 1 ed fractures at 50 , i nf; 11 pd
~~I~_' with chlorite.
\ 'I' 1 ~~"_\:~ 88.7-89.2, closely fract~red along
F-I/_', incipient weakness at 35 .
\, \/\ -'\'-,,'
;' I _ \
N ," \ " -I _-I ,
~ \ ,-..., J~} ~ ',",,'" 94. 0, fractured, pl anar, smooth, v. ~ ~~~i narrow, at 45 , infilled with chlorite.
.)'''', .... 1 ,/ ::/~'
~f"" ""
I
.......
f/~~\ 97.0, fracture, Blanar, slightly rough.
~F,\' v. narrow. at 45 , clean .
_ ..... i-----+-~..:.I ... /r..:.,!_h 98.2. fracture. planar, sl. rough, v.
narrow, at 45 , clean.
;1 ........
100-
-98.6-99.0, mafic zenolith
-Bottom of boring at depth 99.8
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
I
Converse Consultants
Remarks (Water Loss and Color, Casing Record, Time of Drilling, etc.)
run blocked
RWB
SD-88
R. W. Beck and Associates
DRILL HOLE WATER TESTING Hole No. DH 102
Project Haines-Skagway Hydroelectric Feature Left abutment Sheet --,~ ___ of _1 __
Depth to Water Table @ surface Height of Swivel above Ground see remarks Size of Hole Nx \~;reline 3.0" di
Test Equipment Wi rel j De packer Drill Foreman B Ilmphreys Inspector_----I.C"J:p:.QB~ __ ~_
Time Period Depth (Feet) Loss Pressure Date of Test Top of Depth Remarks
Begin End (Min.) of Gallons GPM (psi)
Packer Boring
August 11:00 11:05 5 63.0 99.8 22.9 4 .. 58 15 Single pneumatic
29/1981 11:06 11:11 5 36.2 7.24 30 Packer used
11: 13 11: 18 5 50.5 0.10 45 Top of water
Test 11:20 11:25 5 63.2 2.64 60( )Swivel at 3.5 ft. above
1 11:26 11:31 5 53.2 0.64 45 ground surface. Ground
11:33 11:38 5 26.5 5.30 30 water level at top of
11:40 11:45 5 water gain +47.0 9.40 15(;; )casing
11:46 11:51 5 water gain +16.3 3.26 O(n
(1) Leakage around pack
er estimated loss 19pm
(2) A positive gpm out-
flow from boring.
Test 12:00 12:05 5 23.0 99.8 26.8 5.36 15 Top of water swivel
2 12:06 12:11 5 39.3 7.86 30 at 3.5 ft. above ground
12:12 12:17 5 13.2 2.64 15 surface
! I ! I !
I-w
W
Lt...
700
680
660
~ 640
620
600
580
560
Ground Surface
Overburden
~RO--?G d" . h 1 I3ED CK: rano lOrlte, s 19 t Y
weathered to unweathered, medium
to widely fractured, unweathered
and widely fractured below 10.0'.
----Andesite. intrusive dike, unweathered,
medium fractured
Granodiorite, widely fractured
~closelY fractured
""----Tota 1 Oepth 99.8'
WATER PRESSURE TEST
1 12.64 9pm at 60 psi
2 7.86 9pm at 30 psi
SUMMARY LOG DH-102
Alaska Power Authority
WEST CREEK PROJECT
for R.W. Beck and Associates, Inc.
Converse Consultants
Project No.
81-5165
A-2
\
-j
t
t
RWB-487B DRILL HOLE LOG Hole No. DH 103
Project Haj nes-Skagway Hydroel ectri c ProjQct Feature Left ab'ltmer:tt Bearing N4QE
Coordinates N2814839. E2362115 Ground Elevation 658 9 Angle with Horizontal_.....:S).\,OJ-° __
Nx Wireline 100 9 9/25/81 9/26/81 Type of Hole ________ Total Depth_-=...::...:....:·~ ___ Start _-'-'-~:""'::"';"--__ Finish
none Water Level -Depth, Elevation, Date ________________ Logged By C P Benson
Drilling Co. Wyman Construction Driller Butch Umphry
Angle Depth %
Elevation Rec.
& Size Hole, RQD Box No.
-
-I-r--100 --0
5-1QQ
40 -100 -20
---
10-
...... -
x 90
0 ---co 78 -
-
15-
-
-:
--2L-
-
I-I-95 -
--80 -25 __
---
---
3a-J100
. 67
N -X
0 -co -
35-
-
-100 --91
-t--I-40
1/,;
-\'-' ; , .... , ~
,~t , ..... ,'/
I ... ,-~;'\
'oJ "'*/ "i' '-1/ , \/,-
!.",,:,I
'"----/~ -~ :",f
" ,'\ I
"".." " ;,I,~,
1--\':" '
":I..;i , ..... " ", \-t'
t~""!,"
'..:'"1~'
1 ...... ,-' .:-,1" ~.! ~ I~ ,,':,
• \ I ", 1"",--\ -,
':;-;;1:
.... ' -, ..... ,/
',' '/~ ,I _ ,/
' .... ' I"
'_'':-1
~f~\,~,
" I ,:'_ ... -" \ / ,~\ 1,/
~,.. /, ..... / 'I' \-
\ "" .... /,; "-
~, /1 /, ... "
... -\ I,
'.! <,I.-", ...... / ,
~ ..... \ '..-/
1'1 -, /,-.... '", ~\ ... ' -1_','
I, ..... ,-",;, ' -. ,-; _,I ,.. I
.......... 1
1/"
I _\ I
-';( I~-/
'I I, \
\ -', ,,-... ..' ~\
...... , \ .... -,. ,\ ,\
I" ..,. ..... , ,
'/\/
-,I ,/ 1,,1
~/~""[
..... '-~I-'l
I ~ \,
\ " I ... / 'I -;,
Classification and Physical Condition
Forest Duff, dark brown; wet, soft.
(2. 0-36.7)
Granodiorite, gray, speckled black,
medium grained, hard, slightly weather
ed to 10.7,grades to unweathered below
widely fractured with zones of medium
to very closeofractures, with apparent
dips of 50-80 , planar, slightly rough
very narrow, infilled with iron oxide
chlorlte and clay; with alteration
halos around rehealed and v. narrow
fractures .
13.4-14.2, very c60se fractures inter-
secting, at 50-70 , planar, slightly
rough, v. narrow, infilled with quartz
and clay,
17.2-17.8, closely fractured at 50 0 ,
planar, smooth, narrow, infilled with
chlorite. 0
17.8-21.1, medium fractured at 60 ,
planar, smooth, v. narrow, infilled
Water
Pressure
Test
Interval
~i~~_~~~~:i~~~SelY fractured at 50 0 _ --r-
90 , planar and curving, slightly rough.
infilled with chlorite and clay; alter-
ation halos throughout.
23.7-a1.O, zone of rehealed fractures
at 80 .
33.9-a6.7, closely fractured, parallel N
at 70 , planar, slightly rough, narrow, ~
slickensided, infilled with clay and ~
chlorite. ~
36.7-100.9, zones rehealed fractures
with alteration halos .
(continued)
Converse Consultants
Sheet 1 of 3
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc.)
drilled with NW Casin~
to 2.5, 3.5 11 dia.
hole.
drilled with Nx Wire-
line core without
inner barrel to 7.3
~ample 7.3-8.5 I
~ample 14.2-15.51
Poor recovery and low
RQD due to mechanical
fractures to 7.3
drilled with Nx Wire-
line core to 100.9,
3.0" dia. hole.
100% water return
throughout drilling.
run blocked.
RWB-487B DRILL HOLE LOG Hole N 0, ----'DI.I<Hi+-,l ... O ..... 3~-
Project Ha; ceS-Skagway Hydrae1 eetri c Project Feature ---l.L...le;:..fl-tl.---<a"",,,,"by.'1~t~m~e~nHot __ Sheet --6r---of ---,3ir--
AJlgle Depth
Elevation
& Size Hole,
Box No.
%
Rec.
RQD
M
X o c:a
X o c:a
-
-100
-98
-100
50-94'
-
-
-
-
55-
-
-
60-
-~OO ---_ 95
-
65 -
-
-
-
-
-
80 -97
-93
-
-
85 -
Classification and Physical Condition
Granodiorite (cont'd)
59.0-§9.5, very closely fractured, at
45-60 , planar, rough, v. narrow, in-
filled with chlorite.
69.0-69.8, mafic zenolith
73.9-74.2, closely fractured at 45 0
along incipient planes of weakness,
planar, rough, v. narrow, clean.
77.2-77.4, closely fractured at 45 0
along incipient planes of weakness,
planar, rough, v. narrow, clean.
Converse Consultants
Water
Pres~'Ure
Test
Interval
I -r--
I:
V1
<:!J
I-
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc,)
run blocked.
RWB-487B DRILL HOLE LOG Hole No. OH 103
Project Haines-Skagway Hydroelectric Project Feature Left abutment Sheet 3 of --------------------3
AAs!e Depth ~ Elevation
& Size Hole,
Box No.
-
-
-
-
90--
-100 ---97 --
L() 95.-
X
0 -co
11O~ 100
94
-
-
-
-
-
-
-
--i ~
1
~
_I
-
-
-
-
-
-
-
-
-
-
-
-
-
-
.S::
.c'Oll Q.o ~..J
0
;~ \ ~ ~
\\~ \ ....
I \ ",
... 'I .... ,I~ ,'_
;\ ',-,
\ ... I \ .... -\ ....... t
I_/, \_ , ... ,
.~\,,/ -\ .... ,.. ",-~ f ... \/~
~\::: \--
\ ..... \ ' _-,1-:,-,
_':'" I ....
\ I I .... -\\' \/ .... 1 _ ...
.... / , ....
~-\,.~!.
,'-I 1.,/--\ ,,"" . f..( _,
':"/'-,
\ -1\
/' -, .... , ... -
I '; , ....
• I
Classification and Physical Condition
Granodiorite (cont1d)
88.2, fracture at 60°, planar, sl.
rough; v. narrow, infilled with
chlorite.
End of boring at depth 100.9
Converse Consultants
i
Water
Pressure
Test
Interval
N
+->
VI
\lJ
I-
+->
VI
\lJ
l-
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc.)
RWB
50·88
R. W. Beck and Associates
DRILL HOLE WATER TESTING Hole No. DH 103
Project Haines-Skagway Hydroelectric Feature Left abutment Sheet of ... -~-.. ~-.. -.. ----''"---_.---"---
Depth to Water Table Height of Swivel above Ground see rema rks Size of Hole Nx Wi re 1 i ne 3.0" d i ---"----
Test Equipment Wi rel i ne packer Drill Foreman B Ilmph reys Inspector __ -IC..+POflB>--__
Time Period Depth (Feet) Loss Pressure I Date of Test Top of Depth Remarks
Begin End ( Min.) Packer of Gallons GPM (psi)
Boring •
August 15:30 15:35 5 63.0 100.9 0.50 0.10 15 Single pneumatic
26/1981 15:36 15:41 5 4.60 0.92 30 Packer used
15:44 15:49 5 8.90 1. 78 45 Top of water swivel
Test 15:50 15:55 5 14.50 2.90 60 3.5 ft. above ground
1 15:56 16: 01 5 2.80 0.56 45 surface
16:02 16:07 5 1.00 0.20 30
16:08 16: 13 5 0.15 0.03 15
Test 16:30 16:35 5 23.0 100.9 1. 70 0.34 15 Top of water swivel
2 16:36 16:41 5 5.00 1.00 30 3.5 ft. above ground
16:46 16:51 5 0.30 0.06 15 surface
I I
I I
j
,
!
! i
1
680
660
640
r-
LLJ
LLJ
LL
Z .......
z
0
620
....... r-co::: :::-
LLJ
...J
LLJ
600
580
560
Ground Surface
Overburden DH-103
GL~E~F;T~A~B~UYT~M;EENNTT~------------~~ __ ~~~~ '1---.:
BEDROCK: Granodiorite, slightly weathered to
unweathered, widely fractured with zones of
closely fractured rock; unweathered below 10.7 1
•
closely fractured
very closely fractured
Tota 1 Depth 100.9' --,
WATER PRESSURE TEST
1 2.9 gpm at 60 psi
2 1.0 gpm at 30 psi
SUMMARY LOG DH-103
Alaska Power Authoity
WEST CREEK PROJECT
for ~.~. Beck and Associates, Inc.
Converse Consultants
PrOject No
81-516S
A-3
RWB-487B DRILL HOLE LOG Hole No. DH 104
Project Hai nes-Skagway Hydroe] eetri c Project Feature Left~A.:..=b:...::u:...::t:m.:..:..::e.:..:.n...::.t _____ Bearing S 1 OF
Coordinates _....:N..:..:2:...:8:.:1:...;4~5~2~5-!-, -=.E2=.3::.;6:...:2:.:1:...:6:...;4:.....-.. ______ Ground Elevation 619.7 45 0 Angle with Horizontal _-=~):.._L..-__
Type of Hole Nx Wi rel i ne Total Depth ---.lii2,yO+l ~. 5d----Start __ 9.:...1_3-,-0 1,-8-,-1~ __ Finish 10 I 0 5/81
none Water Level-Depth, Elevation, Date ________________ Logged By---l.C..-J::P~B'IJ,(ilR.n~sQIJ.<r:l~---
Drilling Co.
Angle Depth
Elevation
& Size Hole,
Box No.
-
-1
....J
_i
5-
-
-
--
10--
-
--
-
30--
-
-
-
-
40 -
Wyman Construction Driller Butch UmDhry
%
Rec.
RQD
Classification and Physical Condition
Water
Pressure
Test
Interval
TALUS
(0.0-13.5)
Angular boulders with little sand and
silt. moist. loose.
occasional rounded gravel.
BEDROCK
(13.5-201.5)
Granodiorite, gray speckled, black,
medium grained, med. hard to hard, sl.
weathered to 28.0, grades to unweather-
ed below, v. widely to extremely, close~
ly fractured with apparent dips of 40-
60°, and 70-90°, planar to curved,
slightly rough, v. narrow to narrow,
infil1ed with iron oxide, clay, ch10rit~
and calcite, alteration halos around
some fractured rock, medium hard in
these altered zones.
13.5-34.90 extremely closely fractured
at 80 -90 , planar, slightly rough.
v. narrow. infil1ed with iron oxide and
clay.
24.9-30.4. widely fractured
30.4-52.5, mediHm to veryoc1osely frac-
tured, at 40-55 and 5-15 ,planar,
slightly rough, v. narrow. infilled
with chlorite, calcite, and clay. °
30.4-34.6, closely fractured at 40
34.6-42.0, medium fractured at 40 0 . T
co
(continued)
Converse Consultants
Sheet of ~
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc.)
drilled with NW cas-
ing to 16.1, 3.5" dia.
hole.
dr.illed with Nx Wire-
line core to 201.5,
3.0" d i a. ho 1 e .
100% water recovery
throughout drilling.
run blocked.
~ample 21.25-22.25!
~ample 24.9-26.61
~ample 34.6-35.71
RWB-487B
DRILL HOLE LOG
Project Haines-Skagway Hydroelectric Project Feature Left Abutment
AJlgle Deplh
Elevation
& Size Hole,
Box No.
-
-
-N
x -
0
i 00 40-
ii-I-_
-
-
Sa-
-
-
-
-
5S-
M
X -0
00 -
-
60--
-
-
-
-i-i-65--
-
-
-
-
70--
-
-
-
-
75--
-
-<:::t
X -
0
00 -
80-
-
-
-
1-1-85 -
100
59
97
S4
100 --
94
100
97
100 --
96
00 --
95
1;!..\;
-I'"
i :::',"
";"',1 , I~
\;;' I). ,.
'-, 1'/':-I , .... ,
.... " I-
" "1 "-
!.. .... '-'" \'~'LI'\
1'1 \' ~~;I,
I' '.::. ... ,J~,
-:.\\~
,\~/ ..... ,..
\ ',,, , .,.,
C:::";,:'
~I':)' . , .... /,~
I~'''''~ I~,\I;-i
......... '\ .• ...'\~ .......
". ,I ...! l'! ,,-,!.
I \ ..... ,.
'~'-/~ \ -, I , ,,\-
~ -1-\ I
\ .. \-
,' ......... -1.,-
\ !..,I'..I
-I j ~ J , ... /
bl-), .... !.. " ... ~I/\-I
., l-;,
" "--:: 1\ /
'1 ..... -1 -, , ...
'\ '--, -,.,\ .....
1_ /'\
' ..... 1, I -/ /. I ,I. , .. , I'
11. (. \
1-'1::; .
..... ' -\. ~ .. -
t ~ '~\ \ . , ,.
-I J~;\/ ... i
..... \ ~; \ J -...... ,:~,~~
(.":",,~_' ,? I,
t .... "\ '" l\~\{""
.....-; '\ ';"' , ...... , ......... \
,I ,_
, ........ '\ , ,,_
'I-\)~~
\"'" -' \ ", " I~'~\'
\ \ ..... _,
_ \ r'"
.... \-\,
..... \, " ':1,,,,,
.... ' ...... 1 ........ 1',
;1 ...... 1...:'"
.... f/ 1/
}/\/ .... \
I ........... I' ( J\I~~
j\::.~1
-( ,I
.... 1-".
-I' 1 "\-d
Classification and Physical Condition
Water
Pressure
Test
Interval
Granodiorite (cont'd)
. ° 42.0-45.6, closely fractured at 40-45 ,
planar, smooth, narrow, infilled with
iron oxide.
45.6-46.7, v. closely fractured at 5-10 P
46.7-51.1, closely fract~red along in-
cipient weakness at 5-10 .
52.S-98.5, grades to v. widely fracture~.
S3.3, fracture at 50°, planar, rough,
tight, infilled with chlorite.
65.7, fracture at 35°, planar, slightly
rough, v. narrow, infilled with chlorit .
72.0, fracture at 60 0 , planar, smooth,
v. narrow.
79.7, fracture at 4So, planar, slightly
rough, v. na rrow, i nfill ed with chloritE.
(continued)
co
Converse Consultants
Hole No. OH 1Q4
Sheet __ 2 ___ of __ S,--_
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc,)
run blocked.
core loss.
RWB-487B DRILL HOLE LOG
~o~ct Haines-Skagway Hydroelectric ProjectFe~ure Left Abutment
AlIgie [)ep til
Elevation
& Size Hole,
Box No.
-
-
90-
-
-
-
-
-
100-
-
-
-
105-
% Rec.
RQD
-100
-100
-
-
110--
-
<.0 -100
x _---~ 115 92
x o co
I
-
-
-
-
-
-
-
-
1130 -
Classification and Physical Condition
Granodiorite (cont'd)
Water Pressure Test Interval
o 98.5-102.0, closely fractured at 60-75 p ~
planar, smooth, v. narrow, infilled with ~
chlorite. ~
102.0-120.7, v. widely fractured.
co
105.5, fracture at 40°, planar, very ~
rough, v. narrow. clean. I~ ~
106.8-108.3, zone of rehealed fractures
with alteration halos, infilled with ~
calcite. .
117.0-118.2, mafic zenolith <.0
~
VI
Q)
~
I-I--
120.8-139.4, medium fractured at 15-55 0
v. narrow to narrow, infilled with
calcite, chlorite, or clean.
123.0, fracture at 40°, planar, slight-
ly rough, infilled wibh chlorite.
124.8. fracture at 45 , planar, slight-
ly rough. narrow. infilled with chloritE 't.n
;~936o:2~i;~a~~r~0~~~~e~: ~~~~~~:e~lean ~
I-
(continued)
Converse Consultants
Hole No. __ D_H_1_0_4 __ _
Sheet __ 3 __ of _....;5::..-_
Remarks (Water Loss and Color, Casing Record, Time of Drilling, etc.)
run blocked.
RWB-487B
DRILL HOLE LOG DH 104 Hole No. _-=-'--~'--__
Project Haines-Skagway Hydroe 1 ectri c Project Feature _--=-Le.=...:....ft..:.......;A...;;b:..u:..t;;.;.m:.:.;.e::.,:n.;..t::..-_ Sheet __ 4,--_ of _-=5,-_
A1:I8!e Depth % Elevation Rec. & Size Hole.
RQD Box No.
-100 -
-98
-
1""-135-
X
0 -a::l
-
-
I-t---100
140---
57 -
-
-
-
145-
100 -
-31
-
-
150
CO
x -100
0 --c:o -63
-
-
155-
-I-t--
-
-100
160---
83 -
-
-
-
165-
-
-
-
-00
170 ---
66 0"1 _
x
0 -c:o ~
-1-175 -ilillL 75
;:!...l
0
~I ; :: ~
I ..... \ I
~I ..... I' Il;~1
, I .... 1 ...... ..... / ..... i" 1 1,//, :::-_ JI'/ ,. /.:: .... \
,),/_.1_\
\ , ........ !..
.... \ 1\ ..... , ........ , "",' ,'. "", I" ;~ ,!.\7 .... '
~"', ~ I~
' .... , I' ' ...
.. \/~f , .... \ 1', !';t ... ,-,/,.
I I" ,'" , 1 ...... ~
'I" .... ........... ';
\ I' .... I"'~
. ,; ........ , ..... ...... \"" . . \ .... '/
,-\ "" " I ':. \",,-
,-( '" iV~.
--i· .... ./~/"!"
:/~/< \ , ,
'1 \-:..!.. ,~~-! .... I"~. ,,,. \::;
.... , .... 1
• ........ 1,.....
;\ (, .
........ 'I -, '" \, ,,1-1 -.... " I~:' /,~
'1-:.,.. ,-",.(
.I ,:::
,'';-, .......... '
.... ' .-.-" I, ... I,""'" .1 ... -, ~~ '.,::~
.... ';,''''' '1 __
\ ...... , .I
'1-\ ';/~\ 1':; / ,'*" -, \-,\
\ "" I .... "" ..... , ..... t;
I,,';
;/1 / .... '
I:::.!-,I,
i' \ .....
''1 -I #,:::./\ ..... "
f.l ..... ,' -, \ ,\ \! .... , ,
''''':'/~ \I_~\l.: , ,
\' '/'
,';'1) ~
I \.1 ... ,
1\"';" -~ , -, !.~I~
~ I I"" ),-:1
.... , ........ .... , \ -; ',-~
,-.!, \'1
... "\' \~ -" ~/' \--~'~ \ I
'\ -I /-
,-/' ..... \ I
, -; I .:
Classification and Physical Condition
Granodiorite (cont/d)
129.9-134.8, alteration halos on re-
healed fractures at 8g o .
132.6, fracture at 55 , planar, slight
ly rough, v. narrow, clean.
139.2-145.2, shear zone, medium hard
to hard, veryoclosely to closely fract-
ured at 60-90 , planar to curved,
slightly rough, narrow, infilled with
clay gouge, chlorite, and calcite;
pervasive alteration of rock. a
139.9-140.2, soft clay gougeoat 40 .
145.2-155.2, fractures at 20 , closely
to v. closely fractured, planar, sl.
rough. v. narrow. infilled with iron
oxide.
Water
Pressure
Test
Interval
-F-
o::t
.f-l
Remarks
(Water Loss and Color. Casing
Record. Time of Drilling, etc.)
~ample 142.0-142.5[
~co run blocked.
I--
.f-l
VI
<lJ
I--
run blocked.
155.2-173.6, medium fractured with run blocked.
zones of close to extremel~ close
fractures at 45-65 and 75 , planar
s 1. rough to smooth, v. narrow, i nfi 11-:"") -,..--
ed with chlorite, calcite and clay,
occasional alteration halos around ~
fractures. ~
167.0-168.8. closely fractured.
N
.f-l
VI
~I
172.5-173.6, extremely closely fracture<-,..L..iL---1
infilled with clay.
(continued)
Converse Consultants
J
RW8-4878 DRILL HOLE LOG
Project Ha i nes-Skagway Hydroe 1 ectri c Projecteature Le ft Abutment
Angle Depth
Elevation
& Size Hole, Box No.
-
% Rec.
RQD
-100 ---
180-97
-
-
I-I-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
i
l
Classification and Physical Condi ~ion
Granodiorite (cont'd)
173.6 0186.1, medium to widely fracturec
at 65 , planar, smooth to slightly
rough, v. narrow, slickensided, in-
filled with chlorite and calcite.
177.0, fracture slickensided at 70 0 .
Water Pressure Test Interval
.-
184.80186.0, medium fractured at
10-90 , planar, smooth, v. narrow, ~
slickensided, some infilled with ca6cit~. ~
186.0-201.5, widely fractured at 65 , ~
planar, slightly rough, v. narrow, in-f-
filled with chlorite and calcite.
Alteration halos ~" thick.
End of boring at depth 201.5
Converse Consultants
Hole No. DH 104
Sheet _--"'=-__ of _--,,5<--_
Remarks (Water Loss and Color. Casing Record, Time of Drilling, e~c.)
core loss.
run blocked.
RWB
SD-88
R. W. Beck and Associates
DRILL HOLE WATER TESTING Hole No. DH 104
Project Haines-Skagway Hydroelectric Feature Left Abutment Sheet_=--___ of --""-__
Depth to Water Table _ ..... O ..... r-!l-'j ___ Height of Swivel above Ground see remark.s---Size of Hole Nx Wi re 1 i ne 3.0" di c
Test Equipment see remarks Drill Foreman ---8..-1 lmph reys Inspector !JAY & CPS
Time Period Depth (Feet) Loss Pressure
Date of Test Depth Remarks Top of (psi) Begin End (Min.) of Gallons GPM Packer Boring
Sept. 15:30 15:35 5 183.0 201.5 0 0 15 Single pneumatic
04/1981 15:36 15:41 5 3.8 0.76 30( )packer used
15:45 15:50 5 0 0 45 Top of water swivel
Test 15:55 16:00 5 0 0 60 4.1 ft. above ground
1 16:03 16:08 5 0 0 75 surface
16: 10 16:15 5 0 0 60 (1) Leakage observed
16:16 16:21 5 0 0 30 around packer
Upper Lower
Packer Packer
Test 17:30 17:35 5 158.0 173.0 2.30 0.46 (2)15 ; Dual pneumatic packer
2 17:40 17:45 5 0 0 30 system used for Test 2
17:46 17:51 5 0.40 0.08 45 through Test 7
17:55 18:00 5 0.05 0.01 60 water swivel 5.4 above
18:05 18: 10 5 0.20 0.04 75 ground surface
18: 11 18: 16 5 0 0 60 (2) Leakage observed
18:21 18:26 5 0 0 30 around packer
Test 18:45 18:50 5 153.0 168.0 0 0 15 Top of water swivel
3 18:52 18:57 5 0 0 30 3.0 above ground surfac
18:59 19:04 5 0.70 0.14 45
19:08 19: 13 5 0.50 0.10 60
19:20 19:25 5 1.20 0.24 75
19:26 19:31 5 0.90 0.18 60
19:32 19:37 5 0 0 30
Test 20:00 20:05 5 138.0 153.0 0 0 15 i Top of water swi vel
4 20:06 20:11 5 0 0 30 9.0 above ground surfaCE
20: 15 20:21 5 0 I 0 45
I 20:26 20:31 5 0 0 60
20:33 20:38 5 0 0 75
20:39 20:44 5 0 0 60
20:45 20:50 5 0 i 0
i
RWB
SD-88
R. W. Beck and Associates
DRILL HOLE WATER TESTING
Project Ha i nes-Skagway Hydroe 1 ectri c Feature Left Abutment Sheet of 2
Depth to Water Table Dry Height of Swivel above Ground see rema rks Size of Hole Nx Wi re 1 i ne 3.0 lid i a
Test Equipment see remarks Drill Foreman S. Umphreys Inspector DAY & CPS
Time Period Depth (Feet) Loss
I Pressure Remarks Date of Test Upper Lower (psi) Begin End (Min.) Packer Packer Gallons GPM
Sept. 20:50 20:55 5 123.0 138.0 0 0 15 Top of water swivel
04/1981 21:00 21 :05 5 0 0 30 3.0 ft. above ground
Test 21:06 21: 11 5 0 0 45 surface
5 21:12 21:17 5 0 0 60
Test 21:22 21:27 5 108.0 123.0 0 0 45 Top of water swivel
6 21:45 21:50 5 0 0 15 8.3 ft. above ground
21:51 21:56 5 0 0 30 surface
21:57 22:02 5 1. 70 0.34 45
22:03 22:08 5 0 0 30
Test 24:30 24:35 5 91.5 106.5 0.20 0.04 15 Top of water swivel
7 24:40 24:45 5 1.10 0.22 30 4.5 ft. above ground
24:46 24:51 5 7.50 1.50 45 surface
24:52 24:57 5 3.50 0.70 30
Top of Depth
of
Packer Boring
Test 15:00 15:05 5 33.0 201.5 25.40 5.08 15 Single pneumatic
8 15:08 15:13 5 34.70 6.94 30 packer used. Top of
15:15 15:20 5 42.70 8.54 45 water swivel 4.1 ft.
15:25 15:30 5 0.10 0.02 30 above ground surface
I
I
I
DH-104
l
600
580
560
I-540
LLJ
LLJ
Ll-
:z:
<:)
~ 520 c::c >-
LLJ
.....I
LLJ
500
480
460
Ground Surface DAM AXIS
TALUS: Angular boulders with sand/silt matrix
Medium fractured,
unweathered below 28 1
West Creek
fractured
widely fractured
/
~EDROCK: Granodiorite, slightly
weathered, widely fractured to
zones of extremely close
fractures. Unweathered below
28.0 I.
closely fractured
8 /Widel Y fractured
WATER PRESSURE TEST
1
2
3
4
5
6
7
8
.76 gpm at 30 psi
.08 gpm at 45 psi
.24 gpm at 75 psi
0.0 gpm at 75 psi
0.0 gpm at 60 psi
.34 gpm at 45 psi
1.5 gpm at 4!:i psi Total Depth 201.5 1
8.54 gpm at 45 psi
SUMMARY LOG DH-104
Alaska Power Authority
WEST CREtK PROJECT
for R.W. deck and Associates, Inc.
Project No.
81-5165
Drawing No.
Converse Consultants A-4
RWB·487B DRILL HOLE LOG Hole No. _-"D:,wHi......&1",O>L5 ~ __
Project Ha i nes-5kagway Hydroe 1 ectri c Project Feature Ri ght abutment Bearing _5_1_0_E __
Coordinates N2814210. E2362140 695 9 cnO Ground Elevation. Angle with Horizontal _--l!2.1.l._.l...-__
Type of Hole __ Nx_lv_i_r_e_l_i_n_e __ Total Depth_---=1:..:0:...:0:...:.-=8~ __ Start_-=1..::.0.:.../0.::...8~/--=8:..:1:.....-__ Finish 10/09/81
Water Level -Depth, Elevation, Date ____ no_n_e ___________ Logged By-..:.C:,:P...:B:....,:&:.....=D.:...:A..;..y ____ _
Drilling Co. Wyman Construction Driller Butch llmphr,;l
Angle Depth
Elevation
& Size Hole, Box No.
-
-
--
5-
--,
-
-
-......
-
-
-I--
%
Rec.
RQD
N 35 -86
~4s x o co
-
Classification and Physical Condition
Forest Duff nrlrk hrnwn wpt c:nft
COLLUVIAL SOIL
(1.0-8.9)
Silt, brown, little fine sand, moist,
med. dense.
BEDROCK
(9.8-100.8)
Water Pressure Test Interval
Granodiorite, light gray, speckled
black, medium grained, med.hard to hard,
slightly weathered to 10.9 grades to
unweathered below; medium fractured
with zones closely to v. closely fract
ured with apparent dips of 20-80 0 •
planar, smooth to rough, narrow, in-
filled with iron oxide. clay, and cal-
cite, with zones of alteration.
26.4-40.3, hydrothermally altered to
gray green, closel~ to v. closely
fractured at 20-70 , with zones of re-
healed fractures, planar, sl. rough,
v. narrow, infilled with chlorite,
calcite and clay.
31.0-33.8, shear zone, very closely
fractured, wits clay seam at 33.0 1
,
8' wide, at 80 .
35.4-38.0, zone of closed fractures
with alteration halos ~"wide, infilled
with ca 1 cite
1_.--
N
+-l
Vl
Q)
I-
Sheet of 1
Remarks (Water Loss and Color, Casing Record, Time of Drilling, etc.)
dri 11 ed wi th Nw
Casing to 9.8, 3.5"
dia. hole.
drilled with Nx Wire-
line core to 100.8,
3.0" dia. hole.
Intermittant water
loss up to 50%
throughout boring
~samp1e 12.5-13.3]
Run blocked.
<2amp1e 20.41-21.25 I
Intermittant water
loss 26.4 to 40.3
run blocked.
Core loss 33.8-34.2
RWB-4878
DRILL HOLE LOG Hole No. _...I.D.u;HJ..-,]LJO .... 5;J.-__ _
Project Ha i nes-Skagway Hydroel ectri c Project Feature _--=.R.:..;i:...;g2.:.h.:...:t:.......:a:..:b:..:u:...:t~m:..:.:e::..:n..:...t=--_ Sheet _-=-__ of __ 3=--_
AAa!e Depth % .Si Water Remarks
Elevation .c"" Pressure (Water Loss and Color, Casing
& Size Hole, Rec. 0.0 Classification and Physical Condition Test Record, Time of Drilling, etc.) RQD ;:!....l Box No. 0 Interval
I _I::::
Granodiorite (cont'd) -(,\ '-
-\1/ ;-,"", 40.3-100.8. grades to v. widely fract--"/,'; ured. with 8ccasional medium fractured 100 .. "", .; I -,,'!\; " zones at 25 , planar, rough, v. narrow
83 ,_" clean, along planes of incipient weak--"i ,';;:'
45-.. , ness. ",I I,
'/ ..... l
~I--• II'~ I~ l-.":,,,--........ 1' ,
100 .. " ..... , -'. .... ). \ , ..... ..,."
-100 ~ , ..... t "' ..... ~::/i/r
50-:"'" .(, run blocked. -', --, " ..... ' .... ', ., \-". -100 ~ .... ;;~\ -" , ---~_\-:, .:"", I.....,
I 100 /1-.....
I -. \ _1/
,/\" I
55-.. ./,1,,,, ,'" 'I. , -"I~'..~""\ .... , ..... -
\" "--... -_1, ......
,/ I .... ---\1\ --,
-\ ','!. ,.
100 ./-, " -::'-" / M 60---~""'\.I' ~ 100 /\-:.1 ... X -/,"""" 0 -\ ..... ' co ...... ",
N ,---· , -, -f; \; ...., -....... '-\ VI 1-'1-QJ -... 1-\ ... I-,"'f-
I-t-65-':' ... ' I !", I .....
-'( ..... ' ~, 66.9-67.8, rehealed fractures at 80 0 ... \~'.:""
1-\ I with alteration halo kit to ~II thick. lUU -.... -..... ' .... \ \ 4 -72 :.:\,;~ .....
"'-..... \' \ I -., ..... ',.,.. " · , .... ,"-
70--1'-" blocked. , .... -"' ,-\ run .... -\ ~ -~OO \' ~/'~
---~'\'I ~
100 ..... /-,
-\ ,"'. -I ...... , .... ;;
/~:-( -I' -~ .......... ,
75 -', .... ; ! ,-, ,-I
.... -/" -,1 ..... 1 .... i .. \ -... ~ i ~ ,,' '"
""" -.' -I" ~/\'.,~' x -)J~' .... 1 0 ''''I -co ~~'...I~ -00 I .... '~ I' 80 ---" --, ....... I ;, 96 -~""'I
+.:I -!",-\ !. ~~ VI .. /,"'" / Q) -, ..... 1,( ( I-'...., \,~ --' .......... , "
I-t---""I/~-
I" \ .;
(continued) --RCi " .........
• t - \ I
Converse Consultants
RWB-487B DRILL HOLE LOG Hole No. _-=D..:.,:H-=.1.:.0.:.5 __ _
Project Hai nes-Skagway Hydroel ectri c PrOjectFeature_....:R..;,.',:..;· g::c:h..;,.t:......:a:,:b:.;u:.;t=m.:.,::e:.;n..;,.t=-_ Sheet __ 3,,--_of _--:::..3 __
AIIs!e Depth % .':1 Water Remarks Elevation -5,bl: Pressure ~Vater Loss and Color. Casing
& Size Hole. Rec. ;:.,3 Classification and Physical Condition Test ecord, Time of Drilling, etc.) Box No. RQD I.:) Interval
... .I \ ...
I' I ..... Granodiorite (cont'd) -_ I'tO' , \ ... -, 8l.8-~4.2, closely to medium fractured -"\1 --'\ I'I". at 25 , planar, smooth to slightly -~~\ ~\ .. rough, narrow, clean . 100 \-\;' ...... --" -'''''';' \ ~ 90-98 ,-, -Vl , '\_ \' aJ \ 1'_ I.,., I--\'-\~ ,
I --, .... --,I..! -,
..... 1\ .
-\ I -~,
"\/-~ -1-' i-:'/~';
I.C') 95-\ -}-.... . /' -, x ·-7 t": 0 -co \1' "'" I ~;::,~ N
ilooi
-,-.,\. 97.0-97.3, fractures at 25 0 along ~ .... I.,. "'7 ~ Vl 1'1 -incipient weakness. aJ 100 1'--\ 1 .. I'" \ I
100
~\; ....
_I" I' .... , \-
-End of boring at depth 100.8
-
-
-
-
-
-
--
-
-
-
-
-
-
-
-
-
--
-
-
-
-
-
-
-
I
-
i -
I i
Converse Consultants
RWB
SD-88
R. W. Beck and Associates
DRILL HOLE WATER TESTING
Project Hai nes-Skagway Hydroelectri c Feature Ri t abutment
Depth to Water Table Dry Height of Swivel above Ground see remarks
Hole No. DH .-&1."...05"'--__
Sheet 1 of 1 -=----_.-
Size of Hole Nx Wireline 3.0"di
Test Equipment _-'WL.Ji..l.r ..... e~l..LJj nWe"'-l"P""a ..... c.wke ..... r'--___ Drill Foreman -.a.... Umphreys Inspector_---'C ....... p..l.Bl--___ _
Time Period Depth (Feet) Loss Pressure Date of Test Top of Depth Remarks
Begin End (Min.) Packer of Gallons GPM (psi)
BorlnCl
Sept. 13:05 13:10 5 53.0 100.8 0 0 15 Single pneumatic
09/1981 13: 11 13:16 5 0 0 30 packer used. Top of
Test 13: 17 13:22 5 0 0 45 wa ter swi ve 1 3.4 ft.
1 13:25 13:30 5 0 0 15 above ground surface
Test 14:00 14:05 5 23.0 100.8 1.40 0.28 15 Top of water swivel
2 14:06 14: 11 5 2.70 0.54 30 3.4 ft. above ground
14: 15 14:20 5 0.10 0.02 15 surface
i !
I ! i i
I-w w u...
z ......
z a ......
l-
e:(
:::> w
700
680
660
cd 640
620
600
Ground Surface
Overburden
RIGHT ABUTMENT
unweathered below 10.9'.
BEDROCK: Granodiorite, slightly weathered to
unweathered, very widely fractured zones
medium to very closely fractured
shear zones(31.8 -33.0 and 39.4 -40.3)
hydrothermally altered Granodiorite, closely to
very closely fractured
unaltered Granodiorite, very widely
fractured
,,----Total Depth 100.8'
WATER PRESSURE TEST
1 0.0 gpm at 45 psi
2 .54 gpm at 30 psi
SUMMARY LOG DH-105
Alaska Power Authority
WEST CREEK PROJECT
Project No,
81-5165
for R.~. Beck and Associates, Inc. ----------------------~----------------------~~~------
Converse Consultants A-5
\.
RWB-487B· DRILL HOLE LOG Hole No. _...JD.JJH::I.-,lI.J.O.u;6)...-__
Project _H_a_i_n_e_s_-_S_k_a.::.gw---.:aY::.-H....;Y:,..d_r_o_e_l_e_c_t_r_i_c_P_r...:.o..::::j...:.e...:.c...:.t_ Featu re __ I _n _ta_k_e_S_t_r_u_c_t_u_r_e ___ Bearing ____ _
Coordinates_-.!.!N.:2~8~1.::!4.:2~1.::!.S_._.!:E.:2.::!.3~6~1.i!.9.!-7.i!.9 _______ Ground Elevation 723 4 Angle with Horizontal_....:9z.l.0LO_~
Type of Hole ...;...._N_x_W_i _r_e_l_i n_e __ Total Depth __ .:..7,::.S.:.. :.2 ____ Start _--,1~O~/..!O~6:.L/...::8~1:..-__ Finish _~1uOu../..l.oO!.L7.J.../.l.l8 ... 1 __
Water Level Depth, Elevation, Date ____ n_o_n_e ____________ Logged By_::.D_A:....:.....:..Yo:::.:...:.ne=.;m::..:..:..i .::.t::.S.::.U __ _
DrilhngCo. Wyman Construction Driller Butch Ilmphr~
Angle Depth %
Elevation Rec.
& Size Hole, RQD Box No.
-x: o
CO
x: o co
-
15-
-
-
-
-
-
35-
Classification and Physical Condition
Forest Duff, dark brown, wet, soft.
BEDROCK
(2.6-7S.2)
Granodiorite, light gray, speckled
black, medium grained, with occ. mafic
zenoliths, hard, unwea~hered; very
widely fractured at 80 to horizontal,
planar, med. rough, narrow, slight
iron oxide staining to 9.0
21.2-22.2, fracture at 80 0 .
23.3-24.0, fracture at 80 0 slightly
weathered.
27.4-27.6. fracture at 90 0 .
Water Pressure Test Interval
-
!
(continued) I
Converse Consultants
Sheet of 2
Remarks I (Water Loss and Color, Casing Record, Time of Drilling, etc.) ,
dri 11 ed wi th NW
casing to 4.0, 3.5"
di a. hole.
4am Pl e 5.3-6.33 I
100% water return
( i ntermittant)
drilled with Nx Wire-
line core to 75.2.
3.0" dia. hole.
<2amPle 14.16-15.11
run blocked.
RWB-487B
DRILL HOLE LOG Hole No. __ D_H_l_O_6 __ _
Project Haines-Skagway Hydroelectric ProjectFeature Intake Structure Sheet 2 of 2 -------------------------------~~--
All g!e Dep th Water Remarks Elevation Pressure (Water Loss and Color, Casing
& Size Hole, Classification and Physical Condition Test Record, Time of Drilling, etc.) Box No. Interval
" "I
Granodiorite (cont'd)
.. -,I _
) .... '11 ',-,\:, ,
. ,I ~l
......... 1 .... ' '-! ..... ! {I
"I \/
45 100 / ,1-\
!,-.... ~/:
100 _ i ..... -... '
"" ":, f"
jJ ~J ----
.... ~J ~I\
').':::":
"'" "~' /
20°. r,.!. I:": ~ 49.0, fracture at ... \.". .... 50 1-\ {\ .......... , ......
100 ';.' (,!,.. --,,)/_' I M 99 ... 1\"" , .... ,\
X • I~ \. .. 0 .... I,. co "". "
" "" I
55
!, ~\/'
\',..,1 ""
I"" "I' ,-" ....
.... ' \-; -, , -,
''''''',' "I ..... , .... ,,::-1:
:; \ ..... '-,
60
,/,,_\ -.... -'~..!I
100 -I .... , ,,~ \
100 ,'':'1''
('/1" ~ample '-I' ,
63.1-64.2 -\-
\ .... I "
..... ' ...... 1 ......
65 .... J,-
.... ,-/ ...., ,," \ II) ( -I"~ QJ -J, ..... f-::" ,
100
70 100 run blocked. o::r
x
0
CQ
175
End of boring at depth 75.2
Converse Consultants
RWB
50-88
R. W. Beck and Associates
DRILL HOLE WATER TESTING Hole No. DH 106 ------
Project Haines-Skagway Hydroelectric Feature Intake Structu_r_e ___ sheet_-=--___ of --=-__
Depth to Water Table Dry Height of Swivel above Ground see remarks Size of Hole Nx Wi re 1 i ne 3. Oil di c
Test Equipment Wi re 1 i ne packer Drill Foreman B. Umphreys Inspector CPS
Time Period Depth (Feet) Loss Pressure I
Date of Test Top of Depth Remarks i
Begin End (Min.) Packer of I Gallons GPM (psi)
Boring
Sept. 10:55 11:00 5 11.2 75.2 0 0 15 Single pneumatic packer
07/1981 11:00 11:05 5 22.5 4.50 30 use. Top of water
Test 11:05 11: 10 5 3.7 0.74 15 swivel 2.0 ft. above
1 ground surface
I I
i : I I I i i i :
i
l.
C
I-
LLJ
LLJ
lJ..
z: .......
.......
I-
«:(
:>
LLJ
--1
LLJ
740
720
700
680
660
640
Ground Surface
DH-106
Overburden
INTAKE STRUCTURE
BEDROCK: Granodiorite, unweathered,
very widely fractured
1
---Total Depth 75.2'
WATER PRESSURE TEST
1 4.5 gpm at 30 psi
S'UMMARY LOG DH-106
Alaska Power Authority
WEST CREEK PROJECT
for R.~. Beck As Inc
Project No,
81-5165
Converse Consultants A-6
,
RWB-487B DRILL HOLE LOG Hole No. _...L.Du::HL...l1.LDI..L7 __ _
Project Haines-Skagway Hydroelectric Project Feature Right abutment Bearing _S_6_2_E __
Coordinates _---'N..lJ2i=..lS"'1""'3"""9,(,:4I.,,5'----"Eo..Io2 .... 31.,l,6u1 .... 9:.loCO!..o<5~ _____ Ground Elevation 715 . 2 70° Angle with Horizontal_-,_L!._.l...-__
Type of Hole Nx Wireline. Total Depth 101.0 Start 10/07/S1 Finish lO/OS/Sl
Water Level Depth. Elevation, Date _____ ..:..n:..:o..:..n:..::e:....-_________ Logged By _......:C;...P...::B_&_DA_Y ____ _
Drilling Co. Wyman Construction Butch Umphry 1 Driller Sheet of 3
Elevation Rec.
& Size Hole, RQD Box No.
Classification and Physical Condition
Water
Pressure
Test
Interval
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc.)
Angle Depth % EI
~-----+_---r ------~CO~L~L7.U~V~IA~L~SO~I~L---------~----~-d-rl-.1-l-e-d-w-i-th--N-W--~
(O.O-S.l) . t 6 a 3 S"
x o c:c
N
X o c:c
-Sand, brown, fine to medium grained, caslng 0 . , .
_ trace silt occ. cobble to 6" size; dia. hole.
_ moist, medium dense.
-
-
lS-
-
-
-
2S-
BEDROCK
(5.0-101.0)
Granodiorite, light gray, speckled bla<k,
medium grained, hard, unweathered; widEly
to medium fractured,zones of very ClOSE
fractures and shear zones, with apparert
dips of 20-90°, planar, sl. rough,
narrow, ;nfilled with chlorite, calcitE
and clay gouge in shear zones, alter-
ation halos J.;;_~II thick around rehealed
and very narrow fractures.
23.2, fractures at 40°, infilled with
chlorite.
I-r--
36.6-40.7. shear zone. hydrothermally
altered gray green. med. hard. extrem8-
ly to very closely fractured at 80-90 ,
planar, s1. rough, narrow, infilled wiih
rl:::.
(continued)
Converse Consultants
N
+-'
V'I
(])
I-
drilled with Nx Wire-
line core to 101.0,
3.0 11 dia. hole.
100% water return
throughout boring.
run blocked.
RWB-487B DRILL HOLE LOG DH 107 Hole No. __ ...;....--=:....::..-__
Project Hai nes-Skagway Hydroel ectri c Project Feature __ R_i....:g=-h_t_a_b_u_t_m_e_n_t __ Sheet __ 2 __ of _-=-3 __
APgle Depth
Elevation
& Size Hole,
Box No.
% 1: "-<) Pressure (Water Loss and Color, Casing 1!J Water Remarks
____ RHQecD· ~o _~_~C71_a_ss7if~ic_a_ti,o_n_a_n~d7p~h~Y_Si_Ca_l_C_o_n_d_it_io_n ___ ~~T_e_sTt-4_R_ec_o_r_d,_T_i_m_e_o_f_D_r_il_li_ng_,_e_tc_._}4 , Interval
_ r-;~I'~_ Granodiorite (cont'd)
M
X o
a:l
1-----11'\"-1 39.0-40.7, extremely close fractures, ,,\~:fl'\ -",'1..\/ ~_~II soft, clay gouge.
"'1-40.7-49.0, medium fractured at 40-60 0 , '::/~ ~\\ '" -
_ 100 /1'/'/ planar, s1. rough, v. narrow, infi11ed
~~;0~ with calcite and iron oxide, a1teratior
,""_I;~ halos ~" thi ck around fractures. 45-97
-
-
\ ' .... " ' .... " -\ .... 1 \, .... .;" ....
\ ,\"
-+---j,..~/~/;
":\-/~' -
50-100
_ 48
-
-
-
I /'':t'
-'~\, 1,1' ....
/\/,-
':::1;-':
/ ..... \ ,
1" ... \
,-",' I -, .... "" .f ,.!., '\
-1-..' '" / 55·--"',-"/' 1----1, .... , \.
-", ....
100 ....... , ...
',\..-I -/-/',
O I-~,,\,
49.0-58.2, shear zone, hydrothermally
altered gray green, medium hard, med.
weathered, very closely t8 extremely
close fractures at 70-90 , en echelon,
planar, smooth, v. narrow, sl ickensidec,
infi11ed with chlorite, calcite and
clay, minor iron staining.
-,\-", ~---I\I ........ :,
'-I--... ,/, .....
1-1 ..... 1 '
58.2-61.2, long fracture at 70-90 0 ,
stepped, smooth, v. narrow, infi11ed 60-'~' ... ~ ... I, I 94 -,_1/
---'\//""
80 -..:-1/ ....
-, \\" ':.\'
/ .... ' ,
with calcite and clay. •
N
.+oJ
II)
Q)
I-
~.!\-~ ,,"-\ .. -,'~ ,
\_ t ....
-
-
61.2-76.0, widely fractured withozones
of very close fractures at 50-70 ,
with wideJy spaced rehea1ed fractures
with alteration halos ~-2" thick. T
65-1\-1 I r-..... I .... -J
I)~/~'
f" "\ ,-'\ .....
I -........
-
-\-~ I -" -1----4-, ' \-.... , ,\
-
<::r 70-:
x o
a:l
-
_100
-76
-
75-
-
, ,-
\ -, , ••• :' .... 1
1;/",1
{<'I ,
I~\~/
i/I .... /I
-'",/ ~I:~I -,..' -, \ .... ,
\~\';f
~ (::.\/
I I ....
.,: ... " '/
T \'-~ --II ..... i----iJ ........ / \. -, ...... , ..... ,
\ _'I, " .....
-I' ... ,-
80-~ ~~:~
Ll'"l 100 " -/ \1 -r--\f\~ x o
a:l
85
-
-
-
..... -.,," 1""",
I '/ I
,;\ -1,,-
......... 1'
\ 1\ J ..!
\-; I'
\.'~,::
70.5-71.0, very closely fractured.
(("!'Inti nlll3ri)
Converse Consultants
.....
.+oJ
II)
Q)
I-
I
Core loss 0.6 1
run blocked,
76.0-101.4, all fract
ures mechanical.
RWB-487B DRILL HOLE LOG DH 107 Hole No. _______ _
ProJ·ect Haines-Skagway Hydroelectric Project Feature Right abutment Sheet 3 of 3 ----"'---'--'--"--'-:....-:....:..;..-=--------:....-------=---
AlIg!e Depth .~ Water Remarks
Elevation % ..cOl) Pressure (Water Loss and Color, Casing
& Size Hole, Rec. 0.0 Classification and Physical Condi tion Test Record, Time of Drilling, etc.) i':o-l Box No. RQD 0 Interval
\ ,\ :1
-1;_':.': Granodiorite (cont'd) \.1' I'" -_\_,
/, " J
100 -" -' -, .... , .... -\, -,. --1 - \ \" t.n -100 \/ ' ..... -
x 90-
-,,\,-::
~ample 0 \ ,-.....
90.5-91.7 1 co r}\·,:,; -"", -. ,-" -.... , .... ';\
.......... ",
--:.'~' .... \ \ "-" -( N --\ -\ \-,' ...... +oJ
~95-I ,-I \ til --" +oJQ) '!..'-, till-
\0 -.I' \ /}-, Q)
\' -I-
"I -' X ,,'" \ 0 ~:-_v co -100 ,',\ ..... I __ J
--" , -, 'I
100 -... 100-I .... " :::: '-, '" -r--.... -',
End of bori ng at depth 101.0 -
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Converse Consultants
RWB
SD-88
R. W. Beck and Associates
DRILL HOLE WATER TESTING Hole No. DH 107 ------
Project Haines-Skagway Hydroelectric Feature Right abutment Sheet of _"'--_
Depth to Water Table Dry Height of Swivel above Ground see remarks Size of Hole Nx Wi rel i ne 3. O"di c
Test Equipment Wi rel ; De packer Drill Foreman M. Mckel vey Inspector __ ~DIJjA~YI----___ _
Time Period Depth (Feet) Loss Pressure Date of Test Top of Depth Remarks
of Gallons GPM (psi) Begin End (Min.) Packer Boring
Sept. 06:15 06:20 5 63.0 101.0 a a 15 Single pneumatic packer
08/1981 06:21 06:26 5 a 0 30 used. Top of water
Test 06:28 06:33 5 27.3 5.46 45 swivel 3.0 ft. above
1 06:34 06:39 5 gauge unning backwar ~s 30 ground surface
Test 06:50 06:55 5 26.0 101.0 0 0 15 Top of water swivel
2 06:56 07:01 5 26.9 5.38 30 7.0 ft. above ground
07:02 07:07 5 29.7 5.94 45 surface
07: 10 07:15 5 35.1 7.02 60
07:20 07:25 5 gauge unning backwar ~s 30
I
i I I I i I
I-w
W
LL
z: ........
z: o ........
720
700
680
~ 660
::> w
---l
W
640
620
DH-107
RIGHT \
ABUTMENT
Ground Surface
BEDROCK: Granodiorite~ unweathered, widely
fractured with zones of very closely fractured
rock
shear zone, hydrothermally altered Granodiorite
very closely fractured
Granodiorite,
very widely fractured
;c----Total Depth 101.0 1
WATER PRESSURE TEST
1 5.46 gpm at 45 psi
2 7.02 gpm at 60 psi
SUMMARY LOG DH-107
Alaska Power Authority
WEST CREEK P~OJECT
Project No.
81-5165
for R.W. Beck and Associates, Inc.
Drawing No.
Converse Consultants A-7
•
RWB·487B DRILL HOLE LOG Hole No. _..!.D.u::HL-J].J.OLC8 ____ _
Project Haines-Skagway Hydroel ectri c Project Feature __ S_u_r_g:,..e_t_a_n_k ______ Bearing_..:::-__ _
Coordinates __ -"N~2~3::::.!6::::.!S::!.:9~S~O::W,I__...!:E:..!:2:..\,S.!.J1...,,3!.!:2...:J4:..l<0~ _____ Grou nd Elevation 10] 0 . 0 Angle wi th Horizontal _;zJ.L. __ _
Type of Hole __ Nx_W_,_' r_e_l_i_n...;.e __ Total Depth_---=5:.:0:.:2:.:.:..:2::....-__ Start 1O/11/S1 Finish 10114/S1
Water Level -Depth, Elevation, Date ____ n_o_n_e ___________ Logged By_---JDoIJA~YL...l&L._lC.u;P..J.BL._ ___ _
Drilling Co.
Angle Depth
Elevation
& Size Hole, Box No.
I-r-
x o
CXl
N
--
-
-
S-
--
--
10-
-
-
--
lS-
-
25 -----
-
x 3S-
o
CXl -
-
-
Wyman Construction Driller BlJtch llmphrdl
%
u A \:110 Rec. f'j RQD 0
Classification and Physical Condition
TALUS
(0.0-17.2)
Cobbles and Boulders, angUlar, little
sand; moist, medium dense.
BEDROCK
(17.2-S02.2)
Granodiorite, light gray, speckled
Water Pressure Test Interval
b1ack, medium grained, hard, s1ightly
weathered to 29.6, grades to unweatherE~
below; v. wide1y fractured with zones
of megium to v. close fractures at
30-S0 from horizontal, planar, smooth.
to slightly rough, Y. narrow, infilled
with chlorite, clay, calcite, K-feldspar,
and iron oxide. Alteration halos around
rehealed and Y. narrow fractures to
6" thick.
29.6, fracture at SOO, ~_~" alteration
halo, planar, smooth, v. narrow, clean.
(continued)
Converse Consultants
Sheet of 12
Remarks (Water Loss and Color, Casing Record, Time of Drilling, etc.)
dri 11 ed with NW
Casing to 16.0 ,
4.S" dia. hole.
drilled with Nx Wire-
line core to S02.2,
3.0" dia. hole.
100% water return
throughout drilling.
RWB-487B
DRILL HOLE LOG DH 108 Hole No. _---=_--=-::.....;;.. __ _
Project Ha i nes-Ska 9way Hydroe 1 ectri c Project Feature __ S_u_r....;,9=-e_t_a_n_k ____ Sheet _.-:;2::..-_ of 12
A.IIgle Depth
Elevation
& Size Hole,
Box No.
N
>< o cc
I-I-
-
-
45-
-
-
-
-
-
55-
%
Rec.
RQD
-100
-72
65-
-
-
70 _100
-49
-
-
85
Classification and Physical Condition
Granodiorite (cont'd)
48.3, fracture at 80°, planar, 51.
rough, v. narrow, clean.
60.9-61.8, zone of rehealed fractures,
infilled with chlorite.
66.5-79.5, medium fractu6ed with closel.
fractured zones at 70-80 , planar, 51.
rough, v. narrow, clean to infilled
with K-feldspar and clay.
70.5, fracture at 40°.
72.0-72.2, closely fractured at 40-70°.
75.5-76.0, series of rehealed fracture.
° 77.8, fracture at 80 , infilled with
oxidized clay.
79.5-103.3, widely fractured.
Converse Consultants
Water
Pressure
Test
Interval
I-r
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc.)
run blocked.
run blocked.
run blocked.
ten foot length of in-
tact core. ..
RWB-487B DRILL HOLE LOG Hole No. _....:D....:H--.:1:.,:0..:8 __ _
Project Haines-Skagway Hydroelectric ProjeclFeature Surge tank Sheet __ 3 ___ of _...::.;;2::..-_
AIIs!e Oep th % .S! Water Remarks
Elevation ~1;>j) Pressure (Water Loss and Color. Casing
& Size Hole, Rec. 0.0 Classification and Physical Condition Test Record, Time of Drilling. etc.) RQD E...l Box No. v Interval
1 .... "-I ~"I Granodiorite (cont'd) -i-' '\ ....... _,_;'\ I
-"JI,I ~
1-~ --', I~\: -~ \ /:...,~ .,
--' .... '-'1 , \ '\
90-1j"'_vl!... ~n ... :""
100 ... \ /\ -I I"" ':,,' (I, -100 'I'" ,I .. I I
\ ~ /, ..• \'" --1 .... '-
'/\ ,-.:::" 93 0 3-95.0, long irregular fracture at -,-I .... \ .... '
95-
It 1,-;:'\ 70 , partially closed.
'" I Ii I", ~I -'-....
I .... " I lJ") ". _,I -,,~ ~-, x
0 -v;~.u
c::l 1\ ....
-" ...... , .... I -,,-
lOa-\ -'\ N .... !.. \ .........
" .... 1/ ..... -.... I, .... , 103.3-128.0, yellow brown, medium hard V')
/, ..... -OJ / ,,' / -, .... '/ to soft, slightly to medium weathered; f-
.I" .... -~/ '/ c18sely spaced rehealed fractures at -,-,.., with calcite, granodiorit -100 ; , .... / 60 , infilled ~.
1-105 ---f-~'! hydrothenna lly altered. 1-99 _'/'1 ' , ...... J-:." .......... '" ,,--..... , "
'/ -1 ... /'
-.... '-I ,"',..(,
-" \ .... \-
' .... "1 I /,-/ ---:. \; ~I I
r ... \-.. I
110-1-.... I -",' ..... \ " '1_\ .... -, .... 1' I
'\ .--,:::'
-/--, """', .... /
-I, .... ' . ..1
I "\ .... /\-..... -90 -I' .... \1" -" .... /
115_ --/, /-,
64 / ..... "1.;:...
',I,:' 115.2-116.4, rock is soft. 1.2' core loss. -;,:,
.... -1 -1/ ,-\
..... -", \, -, 1/'/ .......... , ..... / \ -'''1..:'1;''-
1..0 120 . I/\!,..-I ....
x -" I' .....
0 -/ ";1'1
c::l 100 r-;\ ( ..:,
I-:'~/ -74 ~""'~~l -~ I /.; ..... \ \ f--\ .... /, ,. -1-/ \ .... \
125_ ,-.. -
\" I .' f-, ... !'I ~ I .. .',
I-f--I / I __
\'; ,,,
' ---~., ,,\
00 \ .... \-1 -,I .... \' --(-_'_1
90 ""1-
13O --1 .... 1 (continued)
..... ~\';,
Converse Consultants '
RWB-487B
DRILL HOLE LOG Hole No. _..;.D_H--=.10..;.8 __ _
Project Haines-Skagway Hydroe 1 ectri c Project Feature_---.:S--=u:..:..r-"'g--=e---.:t..;.a..;.n..;.k ___ Sheet_4--=. __ of __ 12 __
ARgie Depth
Elevation
& Size Hole, Box No.
,....
x o co
-
-
-
-
-
-100 -
-100
-t--
145-
co
x o
-
-
-
-_100
_ 100
-
co 155-
-
-
-
I-I--
-
165-
0'1
x o co
175
-
-
-
-:
Classification and Physical Condition
Granodiorite (cont1d)
128.0-502.2, v. widely fractured, occ.
closely fractured zones, widely spaced
altered zones, occasional mafic
zenoliths
136.7-137.0, altered zone.
138.0-139.2, altered zone.
140.0-140.2, mafic zenolith
164.8-165.1, fracture at 50 0 , iron
stained alteration halo ~" thick.
Converse Consultants
Water
Pressure
Test
Interval
I
I
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc.)
run blocked.
ten foot length of
intact core.
ten foot length of
intact core.
RWB-487B DRILL HOLE LOG Hole No. __ .:::::O.:..:H--=.l ~08::::-_
Project Hai nes-Skagway Hydroel ectri c ProjectFeature_--.:S::.:U::.:r:..90Le=--t.::.;a::.n:.:.;.;.k ___ Sheet---:5~ __ of _--..1!:..!::.-_
Allgle Depth
Elevation
& Size Hole, Box No.
-
-
-
--il-
x o co
...... ......
x
-
185--
-
-
-
-
-
195-
-
-
-
-
205-
-
-
210-
-
g215-
-
-
-
i
Classification and Physical Condition
Granodiorite {cont'd}
Water Pressure Test Interval
191.6, fracture at 65°, planar, med.
rough, v. narrow, infilled with chlorite.
195.2-196.1, closely fractured at 40-50 P,
planar, rough, v. narrow, infilled with
iron oxide, chlorite, zone of rehealed
fractures with same dip.
200.8-201.7, closely fractured at 45 0 ,
planar, smooth, v. narrow, infilled
with chlorite with iron stained fractur:s,
planar, rough, narrow.
(continued)
Converse Consultants
Remarks (Water Loss and Color, Casing Record, Time of Drilling, etc.)
ten foot length of
intact core.
~ample 209.2-210.41
ten foot length of
intact core.
RWB-487B
DRILL HOLE LOG Hole No. __ D_H_1O_8 __ _
Project Haines-Skagway Hydroe 1 ectri c Proj eC'Feature _--.:.S:.,.:U---,,:...::-...::..:....;..;..;.;; ___ Sheet _-=6=--_ of 12
ARgIe Depth
Elevation
& Size Hole,
Box No.
x o
ct:l
-
-
-
-
-
-
-
-
-
% Rec.
RQD
-100
245--
M 82 ..... -
x o co
-
-
-100 ---
lOa -
-
255-
-
--t-
-
Classification and Physical Condition
Granodiorite (cont'd)
241.4-241.7, rehealed fracture at 85°,
infilled with calcite.
245.1-245.6, altered zone.
245.6-247.7, mafic zenolith
263.1-265.5, closely fracsured, long
continuous fracture at 80 , planar, sl.
rough, narrow, slickensided and iron
stained, altered throughout.
(continued)
Converse Consultants
Water
Pressure
Test
Interval
-:--
.....
V1
Q)
I-
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc. )
ten foot length of
intact core.
ten foot length of
intact core.
ROD low due to sing6e
long fracture at 85 .
ten foot length of
intact core.
RWB-487B DRILL HOLE LOG Hole N o. ----lD.J.IH=+--dl~Ou;S~-
Project Haines-Skagway Hydroelectric ProjecFeature Surge tank Sheet 7 of 12
------~----------------------
AJlgle Depth
Elevation
& Size Hole,
Box No.
-
-
%
Rec.
RQD
_ 100
-87
::; -
X 275-o
c:Q -
-
-'
-I--
-
_100
-100
-285_
310
Classification and Physical Condition
Granodiorite (cont'd)
266.7-267.7. medium hard rock.
268.4-270.4. closely frac~ured. long
continuous fracture at 80 • planar.
sl. rough, slickensided, infilled with
chlorite.
(continued)
Converse Consultants
Water
Pressure
Test
Interval
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc.)
ten foot.length of
intact core.
-[(Sample 293.1-294.31
ten toot 1 engtfl oT
; ntact core.
+'"
VI
<1J
~
I
ten foot length of
intact core.
RWB-487B
DRILL HOLE LOG Hole No. __ D_H_l ...... 0_8 __
Project Hai nes-Skagway Hydroel ectri c Projec1Feature ___ S_u_r..;:g:...e_t_a_n_k ___ Sheet _...;:8 __ of __ 1_2 __
AJlgle Depth
Elevation
& Size Hole,
Box No.
%
Rec.
RQD
-
-1
100 ---_ 100
315-
-
-t-t--
-
320-
-00 _,_1_
-.J 100
-
325-
-
-
-
-
-
-
-
335 -100
-100 t--
co .....
x g
-
-
Classification and Physical Condition
Granodiorite (cont'd)
316.1, fracture at 40° along incipient
weakness.
316.6, fracture at 40° along incipient
weakness.
323.6, fracture at 60°, planar, rough,
v. narrow, clean, alteration halo
evident.
(continued)
Converse Consultants
Water Pressure Test Interval
I
I
Remarks
(Water Loss and Color, Casing Record, Time of Drilling, etc. )
ten foot length of
intact core.
Approx. ten foot leng h
of intact core.
ten foot length of
intact core.
,..
RWB-487B DRILL HOLE LOG Hole N o. _.::.D~H--=-10.::..8=--__
Project Haines-Skagway Hydroelectric ProjectFeature_..:::S:.:u:..:.r..2gc::e~t:.::a..:..:n..:..:k ____ Sheet_..::.9~_of 12
AJlgle Depth
Elevation
& Size Hole,
Box No.
.: % ..c 1:>1) Rec. ~o
RQD O...l
i-r--_
-
-
-
360-
-100 ---100 -
-
0'1 365-......
x -0 co -
-
-
370-
-
-
-_100
"';h75-100
-
-
-
-
380-
-
-100
0 -65 N
x -0 co 385-
-
-
-
-100
-98
-......
N 395-
x o co
400
-
-
-
-
Classification and Physical Condition
Granodiorite (cont'd)
Water Pressure Test Interval
373.0-414.0, zones hydrothermally alter-
ered, yellow brown, medium hard, med.
weathered; medium to v. c60sely fract-
ured, long fracture at 80 ; planar,
sl. rough, narrow, slickensided, iron
stained.
378.2-387.0, very closely fractured along
one fracture, medium hard, medium
weathered.
393.6-399.8, altered zone.
Converse Consultants
Remarks (Water Loss and Color, Casing Record, Time of Drilling, etc. )
~ample 375.0-376.3 I
RWB-487B DRILL HOLE LOG Hole N o. _....:::D~H---=.1~08~ __
Project Ha i nes-Skagway Hydroe 1 ectri c Proj eCt'eature __ --=S:...:u:..:r~g~e=__t::..:a:..:n..:..:k~ __ Sheet _1=..:0~_ of 12
All g1e Dep tit
Elevation
& Size Hole,
Box No.
......
N
X o co
-
-
405-
-
-
-
-
%
Rec.
RQD
I-I---
-100
-86
415-
-
-
-
-
425_
-
-
-
I-!--100
(V)
N
X o co
---_ 100
-
435-
-
-
-
-
_100
-100
-
445
Classification and Physical Condi tion
Water Pressure Test Interval
Granodiorite (cont'd)
404.4-408.0, medium weathered, megium
hard along long fracture at 80-85 ,
planar, 51. rough, narrow, iron
stained.
o 409.5, fracture at 80 , planar, rough,
v. narrow, alteration halo 6" thick.
411.0-411.5, medium weathered, medium
~~~~5~0~~~cture at 80 0 , curved, 51.
rough, v. narrow, infilled with calcite.
414.0-502.2, v. widely fractured, with
v. widely spaced altered zones and
rehealed fractures.
433.0 6440.8, zone of rehealed fractures
at 75 , infilled with calcite, slight
alteration halo ~" thick.
(continued)
N
~
<Il
(lJ
I-
......
~
<Il
(lJ
I-
I
Converse Consultants
Remarks (Water Loss and Color, Casing Record, Time of Drilling, etc.)
ten foot length of
intact core.
ten foot length of
intact core.
....
RWB-487B DRILL HOLE LOG Hole No. _~D;,,;.H~l 0;;,.;8::...-__
Project Hai nes-Skagway Hydroel ectri c Project feature __ S...::u_r-=g~e---=t...:..a ___ n ___ k ___ Sheet ---=1=-=-__ of 12
AJlgle Depth
Elevation
& Size Hole,
Box No.
%
Rec.
RQD
x o
CO
-
-
-
-
455-
-
-
-
-
-
-100
465-100
-
-
-
-
-
-
-
475 -100
-100 -
-
-
-
i100 485---
_ 100
-
490
Classification and Physical Condition
452.7-453.0, rehealed fracture at 75 0
infilled with calcite.
481.2-481.6, fracture at 85 0 , planar,
51. rough, v. narrow, infilled with
calcite, alteration halo 1-Ya" thick
around fracture.
Converse Consultants
Water
Pressure
Test
Interval
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc. )
ten foot length of
intact core.
ten foot length of
intact core.
ten foot length of
intact core.
~ample 486.3-487.7 I
RWB-487B
DRILL HOLE LOG Hole No.-..J..D~H~lJJOl;i.S-__
Project _H_a_i_n_e_s_-_S_k_a....:9=--w_a....:y_H....:y_d_r_O_e_l_e_c_t_r_'_· C __ P_=---e_ctFeature ___ S_u--.:=--_t_a_n_k ___ Sheet _1_2 __ of __ 1 __ 2 __
AAs!e De£th % .:: Water Remarks
Elevation Rec.
..c~ Pressure (Water Loss and Color. Casing
& Size Hole, 0..0 Classification and Physical Condi tion Test Record, Time of Drilling, etc.) RQD ;:...l Box No. 0 Interval
...... , \
Granodiorite (cont'd) I -\ 1--
/ -/\ \
t:/~ ~') -.... \.," '\. .....
_\ -I ....
+-> --.... \'\.
\ \ '-.. VI
..! I~-' <V -~I /I} I-
495-100 ... \/ ' / ,,,,
-,-/ ...... 1
-,I,.,. \ / \ N
\.0 68 ~~.,-, ~ +-> N -or ,-" ~I VI
X ~_'/ ... <V
0 -, \~! .... ;\ I-
co 1'''/'; 1500-= 100
-/ .... -
, .... \', \I
1,;---'\.".. .... 1-1 \
-100 v \ ;\::;1
\~/~-I
-End of bor; ng at depth 502.2
-
-
-
-
-
-
-..
-
--
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Converse Consultants
..
RWB
SD·88
R. W. Beck and Associates
DRILL HOLE WATER TESTING Hole No. DH 108
Project Haines-Skagwway Hydroelectric Feature Tank Sheet 1 of ------~-----------------~~-
Depth to Water Table Dry Height of Swivel above Ground see remarks Size of Hole Nx Wi re 1 i ne 3.0 11 di a.
Test Equipment Wi re 1 i ne packer Drill Foreman ~Umphre'ys Inspector __ ..J.O.u:.Au.V __ _
Time Period Depth (Feet) Loss Pressure Date of Test Top of Depth Remarks
Begin End (Min.) Packer of Gallons GPM (psi)
Borln«
Sept. 11:00 11:05 5 249.0 502.2 12.40 2.48 25 Single pneumatic packer
14/1981 11:06 11:11 5 24.90 4.98 50 used. Top of water
Test 11: 13 11:18 5 46.10 9.22 100 swivel 4.0 ft. above
1 11:20 11:25 5 65.40 13.08 150 ground surface
11:30 11:35 5 +15.00 3.00 50( )
(1) Positive gpm outflo
from boring
Test 12:45 12:50 5 50.0 502.2 7.40 1.48 25 Top of water sw; vel
2 12:55 13:00 5 23.00 4.60 50 3.0 ft. above ground
13:01 13:06 5 55.00 11.00 100 surface
13:08 13:13 5 91.00 18.20 150
13:15 13:20 5 gauge running backwar ds 50
I
I
I
!
I I i I ! I I
..,.
1000
940
880
820
f-w
W
LL
z ,......
,...... 760
f-« :> w
-l w
700
640
580
520
Overburden SURGE TAN K
--7 Ground Surface
BEDROCK: Granodiorite, slightly weath-
ered to unweathered, medium to very
-,----'OI~ idely fractured with occ. zones of
WATER PRESSURE TEST
1 13.08 gpm at 150 psi
2 18.2 gpm at 150 psi
2
1
hydrothermal alteration, unweathered
e 1 ow 17.21.
-----zone of hydrothermal alteration
medium hard, medium weathered
medium fractured
very widely fractured
zone of hydrothermal alteration
medium hard. medium weathered,
medium to closely fractured
widely fractured
--Total Depth 502.21
SUMMARY LOG DH-108
Alaska Power Authority
WEST CREEK PROJECT
for R.W. Beck ana Associates, Inc.
Project No.
81-5165
-------------------Drawing No.
Converse Consultants A-8
•
..
.
"
RWB-487B DRILL HOLE LOG Hole No. __ --I.!jDHI..L-1.1..l0.t.;.9l.-_
Haines-Skagway Hydroelectric Project Powerhouse Project _____ ....:...---=._~ _______ _=____ __ Feature ____________ Bearing ____ _
App N2814100 E2371 d60 + 170 0 90° Coordinates _-...:...:.r:....r:.:..:.r..:::.o:..:.;x:...:._..:...:..::.:::=...:....:::.::!.:::..l..? _=::..:...:....:..;. ~ __ Ground Elevation -• Angle with Horizontal __ ...>Oi_'-"'_-=----_
Type of Hole---:ii:iJe;l.la~r~Q~IlIk1i,.J;r~k .. a--Total Depth_--=1:....;4..:::.1...;, . ..;.,4 ___ Start 10/21/81 Finish 10/22/81
C P Benson Water Level -Depth, Elevation, Date ___ -..L.InJ"lo~n~e ___________ Logged By_-=----_______ _
Drilling Co.
Angle Depth
Elevation
& Size Hole,
Box No.
-
--
-
5-
-
-
-
~ I
10-
-
-
--
15-
-
-
-
-
20-
-
-
-
-
25~
--
-
-
30-
-
-
-
-
35-
-
-
-
40 I
Wvman Construction Driller Butch lJmlJhr~
% '"' :.c llll Rec. 0..0
RQD ;:...J
0
Water
Pressure
Classification and Physical Condition Test
GLACIAL MORAINE DEPOSITS
(0. 0-117.5)
Cobbles & Boulders to 1011 dia. trace
sand.
------------_.-
Sand, gray.
------------_.-
Gravel and Cobbles, trace silt.
-------_.-
(continued)
Interval
Converse Consultants
Sheet of
Remarks
(Water Loss and Color, Casing
Record. Time of Drilling. etc.)
dri 11 ed wi th HW
Casing to 20.5, 4.5 11
dia. hole.
drilled with NW Casin
to 70.0, 3.5" dia. ho e.
RWB-487B DRILL HOLE LOG Hole No. __ D_H_1_0_9 __ _
Project Ha i nes-Skagway Hydroe 1 ectri c Proj eC1F'eature __ ---.:....P.::.o.:..:.w.::.e.:....r:..:.ho=..u:::.:s::..:e=---__ Sheet _-=2,--_ of _....!.4 __
AR8.!e Depth % .2 Water Remarks
Elevation ..c:"" Pressure (Water Loss and Color, Casing
& Size Hole, Rec. 0..0 Classification and Physical Condition Test Record, Time of Drilling, etc.) ~...l Box No. RQD U Interval
rJb"] ac1 at 1'10 r a 1 n e oe~6S1 ts r cont 'Cry '---Gravel & Cobbles to 6" dia., little -sand, medium to coarse, with 1 ens of
-sand.
-
45-
-
-
-
-
50-
------------------Sand and Gravel, trace sil t. ---------
-
-
55-
Gravel -& Cobbles to 8" di a. , little sar d.
-
-
-
60-
, -
-
-
-
65-
-
-
-
-
70------------------Boulders to 14" di a. , trace brown drilled with NO Wire--silty sand. line rods to 97.5, -3.0" dia. hole.
-
-
75-
-
-
-
-
80-
-
-
-
-(continued) 81)
Converse Consultants
"
RWB-487B DRILL HOLE LOG DH 109 Hole No. ___________ _
Project Hai nes-Skagway Hydroe 1 ectri c Project Feature Powerhouse Sheet 3 of 4
A.Aa!e Depth
Elevation
& Size Hole,
Box No.
......
x o co
-
-
-
-
90-
-
-
-
-
95-
-
-
-
-
100-
-
-
-
-
105-
-
-
-
-
110_
-
-
-
-
115_
-.
120--
liO
%
Rec.
RQD
.S:!
.="" Q.o ~,.J
0
-------------------------------
Classification and Physical Condition
Glacial Moraine Deposits (cont1d)
" Boulders to 3 1 dia., trace gray silty
sand.
91.0-94.0, Boulder.
(117.2-141.4)
Andesite Dike
BEDROCK
Water
Pressure
Test
Interval
gray green, fine grained, hard, un-
weath~reg; medium to closely fractured,
at 40-60 from horizontal, planar, med .
to slightly rough, v. narrow, infilled
with calcite, some fractures ir8n stain
ed, rehealed fractures at 40-60 throug~
out, infilled with calcite.
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc.)
drilled with BQ Wire-
line core to 141.4,
2.4" di a. ho 1 e.
Converse Consultants
RWB-487B
DRILL HOLE LOG Hole No. __ D_H_1"",,0_9 __ _
Project Hai nes-Skagway Hydroel ectri c ProjeciFeature _-.:....P..:::o..:..:w..::.e.:..,.r.:..:,h.::,o.::,u.::.s.::,e ___ Sheet ---....:4-.:.... __ of _.....:4 __
AJlg!e Depth .:: Water Remarks Elevation % ..c':.ll Pressure (Water Loss and Color, Casing Rec. 0.0 Classification and Physical Condi tion Test Record, Time of Drilling, etc.) & Size Hole, " , Box No. RQD ........ In terval 0
I~ r-""~"' ... v.,
100/9 ~: "" .) I.. Andesite Dike (cont'd) -y',. .. : : .,
-' , . 134.0-141. 4, medium fractured. ,. I.. .. .., ... y . ' -(' I.. ... v..,
...... J, I.. ,.
') ... .>\.--v ,. v ...
60°,
... ,... 1..,... 134.3, fracture at planar, rough, 135-('.., > v ..,
'" I.. f" '7
00/ '('" ,,""'1 v. narrow, iron stainod. -~,'7\.-"
134.7, fracture 92 .. r 7 ... at 40 , planar, rough, < ... ,.. ~
N -J, '7 ., &. v . narrow, iron stai nOd. .. ~ '" .. .. ",,,, .. x :: ~~ ~: 135.7, fracture at 60 , planar, medium 0 -co
",,') "" ... ~ ... rough, v. narrow, iron stained.
14°-=
... < ) '"
.., '" < ...
",')'" .-
> "'" < ,.
: ~ ; >
-t.nd of Donng at depth 141.4
* RQD values not valid due to undersize -core -
145-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Converse Consultants
t--w
180
160
140
120
t: 100
......
t--
~ >
~ 80
w
60
40
20
DH-109
ALTERNATIVE 2
POWERHOUSE
7--
Overburden:
Glacial Moraine deposits,
cobbles and boulders 4"-10"
with minor sand matrix, gray
--7
BEDROCK: Andesite, unweathered, closely
fractured
Total Depth 141.41
WATER PRESSURE TEST
No testing completed
SUMMARY LOG DH-109
Alaska Power Authority
WEST CREEK PROJECT
for R.W. Beck and Associates, Inc.
Project No.
81-5165
Converse Consultants A-9
RWB·487B DRILL HOLE LOG Hole No. __ D_H_1_1_0 __ _
Project Hai nes-Skagway Hydroel ectri c Project Feature ___ P_o_w_e_r_h...:o_u_s_e _____ Bearing ____ _
Coordinates---'N~2~8~1:!:.:4!.:3~3~0~,I__ _ _.!:E.!:2~3:L7....1.1.l.l.6.>11.3loL8 _____ Ground Elevation 4].3 Angle with Horizontal __ 90 0 _
Type of HOle_:.,Se:.,e;;....:r...:e:.;,:m.;,;:a;,;.r..:,;k,;:.s __ Total Depth_-.....:9::,;;8::,;.;,..:0=----___ Start 10/16/81 Finish 10117/81
Water Level-Depth, Elevation, Date ___ .-:..n_o_n_e ___________ Logged By_--..:C::......:.P-=:B~e.:.:.n.:::.so~n~ __ _
Drilling Co.
Angle Depth
Elevation
& Size Hole, Box No.
-
-
-
-
5-
--
-
-
10-
--
-
-
15-
--
-
-
20-
-
---
25--
--
-
-
3°1
35-
-
-
--
40
Wyman Construction Driller Riltch Ilmphry
%
Rec.
RQD
Classification and Physical Condition
TO.0-72.7) GLACIAL MORAINE DEPOSITS
Gravel, Cobbles, & Boulders, with traCE
sand, boul ders to 18".
Sand & Gravel, fine to coarse, trace
cobbles, to 6".
Converse Consultants
I Water Pressure
i Test . Interval
Sheet 1 of :3
Remarks
(Water Loss and Color, Casing Record, Time of Drilling, etc.)
dri 11 ed with HW
Casing to 25.0, 4.5" ~ia
hole.
drilled with NW Casing
to 75.0, 3.5" dia.
hole.
RWB·487B
. DRILL HOLE LOG Hole No. _D_H_l_l_O __ _
Project Haines-Skagway Hydroelectric Project Feature __ Pc...;o;;;..:w.;:.::e:..:.r..;.;h"'-o.::.u.=..se::o.-___ Sheet_..:::2 __ of 3
APl!!e Depth
Elevation
& Size Hole,
Box ~o.
-
-
--
45-
-
-
-
-
50-
-
-
-
-
55-
-
-
-
-
60-
-
-
-
-
65-
-
-
-
-
70-
-
x 80-
o co -
% .:=
.c~
Rec. 0.0
RQD i::..J
"
53 i::: ~4 ~
') ... ~ ..;..>
.,j >'\ "
I" ~ L,). <
" ~" t"
-"'''':>''''''-1 1----1,., (.'1-
-100
-80
v " ,) "',
.J:'" .....
,., (. j., ')
-"? V A '"
'-" or ,. ,.
~ .. <. .oJ
Classification and Physical Condition
Glacial Moraine Deposits (cont'd)
Sarld&GraveT,fewcobbles to ~ --
SiTIySand &Gravei,fine to COarse--
gravel, fine grained sand.
Sand, gray, fine grained.
BEDROCK
(72.7-98.0)
72.7-94.5, Andesite Dike
gray green, fine grained, hard, un-
Water
Pressure
Test
Interval
weathereg; medium to very closely fract red
at 35-75 from horizontal, planar, sl.
rough, v. narrow, infilled with iron
oxide; occasional lenses of granodiorit~.
72.6-76.2. very closely fractured.
76.2-77.2, granodiorite lense.
77.2-79.9, medium fractured.
(continued)
Converse Consultants
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc. )
drilled with Nx Wire-
line core to 98.0,
3.0" dia. hole
run blocked.
RWB-487B DRILL HOLE LOG Hole No. DH 110
Project Hai nes-Skagway Hydroe 1 ectri c ProjeciFeature _-,-,Po",-,wc:.:e::..:r-!..h:.;::o,-",uc.=.s.=.e ___ Sheet _-'='-__ of _-",3 __
ARgie Depth
Elevation
& Size Hole,
Box No.
.~
% ..c". Rec. ~o
RQD O..J Classification and Physical Condition
" <J>",.""..,..J-:
-• L L A Andes ite Di ke (cont I d)
-100 ':L:>~';, 81.0-82.7, granodiorite lense.
~::::: 82.8-88.0, very closely fractured.
-88 "..::::" 88.0-92.2. medium fractured at 60 0 , -
90-
-
v~ .. :» planar, smooth, v. narrow, with iron
.::: .. oxide infilling.
,.. "'Ii ~ ....
., ".I" f' .I
f"'f'.Io L. ...
_ """.,l>,.
N i OO /O ~{:;>; 92.2-94.5, closely fractured.
x ,,<1., ____________ _
g _ r'!.--,,~I 94.5-98.0, Granodiorite
Water Pressure Test Interval
J 95 I~~; light gray, medium grained, hard, un-
_100 ~.:~ weathsred; closely to v. closely fractured
-52 I' I~\. at 75 , pl anar, rough, v. narrow, iron
../ ' -I c:; t(l i npd
-End of boring at depth 98.0
100-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Converse Consultants
Remarks
(Water Loss and Color, Casing Record, Time of Drilling, etc.)
run blocked.
"
80
Ground Surface
60
DH-110
40 ALTERNATIVE 2
POWERHOUSE
~ 20
LU u...
Z ......
z o .......
I-
~ 0
LU
.....J
LU
-20
-40
-60
WATER PRESSURE TEST
No testing completed
Granodiorite
Granodiorite
Overburden:
Glacial Moraine deposits,
Gravel, cobbles and boulders
with sand matrix. Boulders
to 18", average size 6"-8".
BEDROCK: Andesite, unweathered,
very closely to medium fract-
ured with zones of Granodiorite
very closely fractured
--Total Depth 98.0·
SUMMARY LOG DH-11 0
Alaska Power Authority
WEST CREEK PROJECT
for R.W. Beck and Associates, Inc.
Project No.
81-5165
----------------------...... ~~ ....... ~~ ........ --... ~---... -------~~~-----
(!) Converse Consultants A-10
)I~N
RWB·487B DRILL HOLE LOG Hole No. DH 1 1 ]
Project _H_a_i_n_e_s_-_S_k_a...:9:...w_a-=y_H-=y_d_r_o_e_'_e_c_t_r_'_· c __ Pr_o_J.:;..· e_c_t_ Feature __ P_O_w_e....,rrh_o_u_s_e ______ Bearing ____ _
± 35.0 90 0 Coordinates Approx. N2813400, E2813560 Ground Elevation ____ Angle with Horizontal_of..: __ I01....-__
Type of Hole ___ N __ x ____ W_i _r.:.e..;.l..;.i .;.;,n.:;.e __ Total Depth_---=;.5..;;.0...;.. • ..;;..5 ____ Start _---'1~2::.1./~0::..:3::..1./...::8~1::...__ Finish 12/05/81
none D A Yonemitsu Water Level -Depth, Elevation, Date _________________ Logged By_=--.:..:-....:....:::..:..:..::::..:.:...:....::..:::~ __ _
Drilling Co. Alaskan Enterpn ses Driller Woody HlJnt
Angle Dqlth %
Elevation Rec.
& Size Hole, RQD Box No.
I-I-
N
X o co
-I I
30 -100 -_ 90
-
-100
35--_ 90
-
Classification and Physical Condition
COLLUVIAL SOIL
grained, I
a 29.0, fracture at 80 , planar, smooth,
v. narrow, clean.
Converse Consultants
Water
Pressure
Test
Interval
Sheet of 2
Remarks
(Water Loss and Color, Casing
Record, Time of Drilling, etc.)
drill ed with Nw
Casing to 2.0, 3.5 11
dia. hole.
drilled with Nx Wire-
line core to 50.5,
3 • 0 II d i a. ho 1 e •
run blocked.
RWB-487B DRILL HOLE LOG Hole No. _-=D:.:.H:....:;l..:.l..:.l __ _
Project Hai nes-Skagway Hydroe 1 ectri c PrOjeCtFeature __ :...:PO:::.w:..::e~r:..:.hc~~):::.u:::.Se~ ___ Sheet ---!2=--__ of 2
AIIs!e Depth % ::: Water Remarks
Elevation .&:"'" Pressure (Water Loss and Color, Casing
& Size Hole, Rec. 0.0 Classification and Physical Condition Test Record, Time of Drilling, etc.) RQD E...;j Box No. v Interval
",,, i~
Granodiorite (cont/d) -", ,I "
'--... 100 .... ,' , -,; _ ..... 1
I~ ~-.. .' -100 / ..... / .... .. 1 ...... _'
/\ ..... , -..... , .... ,
45-
-,,-, -,
100 !.. \ / .......
" :-.. 1/ ----I,';J'
-100 '(I'/~
1'/\/
M .... \ .... I -~,; ,-;., x 100 \-..... 1-0 -' .... , .... :::. co -L 50-100 -,,;!,
, 'I'" ,/ .
-End of boring at depth 50.5
-
-
-
55-
-
-
--
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Converse Consultants
60 Ground Surface
40
DH-111
I
Overburden ~
I-
l.J..J
l.J..J
1.1...
20 ALTERNATIVE 1
POWERHOUSE
BEDROCK: Granodiorite, unweathered,
very widely fractured
Z
t-i
z o ......
I-
0::::(
>
l.J..J
...J
l.J..J 0
-20
--Total Depth 50.5 1
WATER PRESSURE TEST
No testing completed
SUMMARY LOG DH-111
Alaska Power Authority
WEST CREEK PROJECT
for R.~. Seck and Associates, Inc.
~ Converse Consultants
Project No.
81-5165
A-11
RWB-487B DRILL HOLE LOG Hole No. __ DIoLHU-.J..l J..l,-? __ _
Hai nes-Skagway Hydroe 1 ectri c Project Feature Powerhouse Bearing S85E Project _____ ..........::.........:......--= ________ '--__
Coordinates Approx. 2813430, E2371400 Ground Elevation _~_11~PAngle with Horizontal 65 0
Type of Hole Nx Wi re 1 i ne Total Depth 75.5 Start-...,;1;;;.;;2;.:../...::..0,,-,9/,-,8;..;;1;..... __ Finish 12/10/81
none D A Yonemi tsu Water Level Depth. Elevation, Date _________________ Logged By __________ _
Drilling Co. Alaskan Enterprises Driller Wood!£ Hunt
Angle Depth % Elevation Rec.
& Size Hole, RQD
Box No.
x o
CQ
-
-00
10-= 88
-
-00
15-~
-
Classification and Physical Condition
BEDROCK
(0.0-75.5)
Granodiorite, light gray, speckled
black, medlum grained, medium hard to
hard, slightly weathered to 22.0 1
Water Pressure Test Interval
grades to unweathered and hard, below
very closely fractured with zones of
extremely close fractures at 20.0 grad~s
to medium to widely fractured with
apparent dips of 40-80 , planar, sl.
rough, v. narrow, iron stained to clea •
13.0-17.0,extremely close fractures.
18.0-19.5, extremely close fractures.
22.0-57'8' unweathered, medium fractur d
at 40-80 , planar, sl. rough, v.
narrow, cl ean.
(continued)
Converse Consultants
Sheet of ?
Remarks (Water Loss and Color, Casing Record, Time of Drilling, etc.)
drilled with Nx Wire
line core to 75.5,
3 . 0" d i a. ho 1 e .
100% water return
throughout drilling.
run blocked.
RWB-481B DRILL HOLE LOG Hole No, __ D_H_I_I_2 __
Project Haines-Skagway Hydroelectric ProjeC'Feature Powerhouse Sheet __ 2 __ of __ 2 __
AR!!!e Depth % ,S: Water Remarks
Elevation .::"" Pressure (Water Loss and Color, Casing
& Size Hole, Rec. Coo Classification and Physical Condition Test Record, Time of DriHing, etc. ) '" , Box No. RQD '"-Interval \.:)
---: t--
\"'_ 1-
, :;;-t l ..... \ Granodiorite (cont1d) .... ,~
\ -.... ' \ \',,'
100
,,, ,\ -.... , I I I .... , \ > --,~ ~-" -100 "-;t ...,.. 'If ..... ,
45-" ,'\ .... , -
/t .... I" -V ",1,,,
,f,,~\I, '/,,, " 47.0-48.0, long fracture at 80 0 , planar, 100 .... " 1;,",. -, ........ , -slightly rough, v. narrow, clean. -98 " v:..., \, I, '_' -.... ,,-
50-\. ',,', " -,' ,;,
~ ~:f ~ I~ .... , -,
M I':' x '...-1\
0 -100 ",,,
co I ;"1-I --1:::1 ~ -90 ~ /",
55-,~~;\
-\~ t ~~ \-~ ~t: .',. ' ..... \ 57.5-59.5, dark gray, medium hard, med. ,"" 1_"', " -100 I' ,-weathared; very closely fractured at ........ '1.,..,' --.... ' ..... ,1. slightly rough, -40-60 , planar, narrow, I-I-54 : '-.... \ , I", i nfi 11 ed with clay and sand. 60-1\'", '\
". ........ 1" I 59.5-75.5, unwea~hered, v. hard, widely -/".,/'-, -/ \' fractured, at 40 , planar, slightly I ' •• ./ _~I-rough, v . narrow, clean. '" .... ,' -100 ...... 1, ......... , .... _/
... \ .... I ---I' 98 ..... " ........
,...~ \. -I 00_ , '1:::--; ~-I:'----/ '..! \' 1\ ,!. .... \'"';
100 .... 1 .... '/:,. \
-,~\; I
.... ", " -100 ~\""'.,,::.1
70_ ,,-I" .... " .... \ .... \' , \ l
'Id" ., .... ,I"
I " • x -1'_' ....
0 -I," co ' .... I'
175-=
100
,:, ... ,.: I
:/~" '" \ I --\' , .... ,' ..... "''''-100 -, "' .... " \.-.... ,'" \ ....
-tno or Don ng at aeptn 75:-5
-
-
-
80-
-
-
-
-85
Converse Consultants
140
Overburden
120
Ground Surface
/'
100 ~
80
60
40
---/'
,/' /' ALTERNATIVE 1
./ /' POWERHOUSE
BEDROCK: Granodiorite, slightly weathered
to unweathered: medium to widely fractured
with occasional zones of extremely close
fractures, unweathered below 22.0'.
Total Depth 75.5'
WATER PRESSURE TEST
No testing completed
SUMMARY LOG DH-112
Alaska PO\lJer Authority
WEST CREEK PROJECT
for R.W. Beck and Associates. Inc.
Converse Consultants
widely fractured
zone medium weath-
ered, closely
ractured
Project No.
81-5165
Drawing No.
A-12
APPENDIX B
BORROW EXPLORATION
B.1 GENERAL
A borrow exp 1 orat i on program was condu cted as part of the subsu rface
exploration program. The program consisted of the interpretation of
aerial photographs and reconnaissance field checking. In potential
borrow areas subsequent work consisted of geologic mapping, excavating
and sampling of test pits, and electrical resistivity soundings. The
i naccess i bil ity of the si te prevented the use of power-operated equi p-
menta
The primary portion of the field work was completed between August 28
and September 8, 1981, with helicopter support provided by Temsco Heli-
copters, Inc. of Ketchikan, Alaska.
The purpose of the exploration investigation was to define the type and
distribution of potential construction materials for use in construction
of the West Creek Hydroelectric Project.
The 1 ocati on and ground su rface el evati ons of test pits, cut banks and
resistivity survey locations were approximated in the field by compass
bearing, tape measurements, and topographic maps. The locations of the
explorations are shown on Drawing 8.
B.2 TEST PITS
A total of seven test pits, TP-1 through TP-7, were hand-excavated be-
tween September 4 and 8, 1981. In addition, four natural cut banks,
CB-1 through CB-4, which are located adjacent to West Creek, were exam-
i ned.
Test pits and cut banks were visually logged by our field representa-
tive; logs of the explorations are included in Appendix B. Representa-
tive bulk samples were obtained from all excavations except for test pit
Converse Consultants, Inc.
B-2
TP-7, where a shallow water table made sampling impossible. Bulk samples
from test pits and cut bank locations were transported to our office in
Seattle, Washington for subsequent laboratory testing. The test results
are presented in Appendix D.
B.3 ELECTRICAL RESISTIVITY SOUNDINGS
An electrical resistivity survey was completed as part of the borrow
exploration program. The purpose of the survey was to obtain general
information regarding the subsurface soil below the depth of the test
pit excavations.
Electrical resistivity is based on the variation of the conductance or
resistance resulting from passing an electrical current through the
subsurface soils. Electricity is conducted electrolytically by the
interstitial fluids. The resistance or conductance of a soil or rock
unit is largely controlled by its porosity, water content and water
quality. Thus, a granular material, such as sand and gravel, will
generally exhibit much higher resistivity than a fine-grained material,
such as silt and clay.
A total of seven electrical resistivity soundings, RS-1 through RS-7,
were completed in the potential borrow site in conjuction with test pit
explorations. The sounding stations are located immediately adjacent to
the test pit. These surveys were completed on September 2 and 3, 198!.
The results of the survey are summarized in profile on Drawing B-1. The
individual resistivity sounding curves are presented on Drawings B-2
through B-8.
B.3.1 Personnel, Equipment and Field Procedures
The resistivity field crew consisted of two staff geologists under the
supervision of a prinCipal geologist/geophysicist. The prinCipal geo-
logist/geophysicist supervised the field operations and the interpreta-
tion of the resistivity sounding survey. The instrument utilized for
this survey consisted of a Bison model 2350 resistivity meter.
Converse Consultants, Inc.
B-3
The Schlumberger electrode array was employed for this study. This
array consists of four electrodes, two inner potential electrodes which
are maintained at a constant spacing and two outer current electrodes
which are moved outward at equal intervals as the survey progresses.
At each electrode spacing, an electrical current is introduced into the
ground through the two outer current electrodes and the potential volt-
age drop due to electrical resistance of the earth materials is measured
between the inner electrodes. The apparent resistivity values obtained
from the field are plotted on double logarithmic paper. These plots are
compared with a set of master curves which results in determination of
apparent resistivity values for each layer and an interpreted thickness
fo reach 1 ayer.
Based on the interpretation of the resistivity values, the profile be-
neath the potential borrow area consists of three resistivity layers. A
surface resistivity layer with values ranging between 1,000 ohms per
foot and 4,900 ohms per foot is interpreted as representing the general
topsoil unit. The intermediate resistivity layer with values ranging
between 40,000 ohms per foot and 190,000 ohms per foot is interpreted
as representing a granular soil unit, probably sand and gravel. The
deepest resistivity layer with values ranging between zero ohms per foot
and 18,000 ohms per foot is interpreted as representing either a fine-
grained silt and/or clay unit or a water-saturated granular unit. In
general, resistivity soundings RS-5, RS-6 and RS-7 indicate relatively
lower values than soundings RS-1 through RS-4. This comparison appears
to be borne out by the test pit logs with a greater amount of fi ne-
grained material being encountered in test pits TP-5 through TP-7.
Converse Consultants, Inc.
RWB 403 -1/2
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
Faoturo Aggregate Borrow Projact Haines-Skagway Hydroelectric Project Holo HQ, TP-1
ArlO D .. i\jnotion Reservo1 r S1 t:e Coordinot .. ,.,.,~28I5a3a, E2359500 Ground Elov.tion 605±2 Dopt" To Ground Wot., Loval none
Motllod of 1.o'V"IOft fiaoa aug Approal ... to Di",o",lon. of Hoi, see remarks Dot .. of lac ... tloll 9Z~-2Z5 Holo Lo"Od By DAY
CLASIII'ICATION SIZE AND TYPE WEIGHT
SYMIOL DEPTH OF CLASSIFICATION AND DESCRIPTION OF MATERIAL MAX.
( .. liT) SIZE ~"-It" -It" LETTER ,RAPHIC SAMPLE TAKEN + ," 6",5"
0.0-0.6 FOREST DUFF: Wet; organi cs; 5°1 10 roots with ~" -OL volcanic ash layer; soft; dark brown. -
-
-TERRACE DEPOS ITS
1-0.6-2.6 SAND AND GRAVEL: Moist; 30% to 45% sand, wel
-graded, fine to coarse; 45% to 55% gravel, well grad-
-ed fine to coarse; 5% to 10% silt; occ. cobbles to
4" di a.; many clasts iron stained and cemented, dense -GW red brown. -
2-
-
-
-~ ...............
2.6-3.5 SAND: Moist; 90% to 95% sand, well graded, -fine to coarse, 5-10% silt; with 1 ens of coarse
SW 3-sand; medium dense; yellow brown. --/3. 4.4 GRAVEL: ~1oist; 68-70% gravel, well graded, "'" -Bag (2) fine to coarse; 28% sand, well graded, fi ne to -Sl coarse; 2% cobbles up to 4" max; less than 5% silt;
GW 4-medium dense; yellow brown
-/4.4-7,0 '" c----SAI~D ---SW
5 -(continued)
"'MARKS!
Test Pit Dimension: 8'L x 6'W x 7'D
RWB-403 2/2
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
Feotur..:.. __ A--=g:...;:g:-r_e-"g __ a_t_e_B_o_r_r_o_w ___ Proj.cu.t -.:..;.H::.;.a __ i :..;..n e:::..s __ -_S:....:k:....:a~g:!...w __ a..:f.y_H_"_y_d_r...:.o...:.e_l __ e:::..c __ t_r _i c ___ P_r_o.....:J::...· e:....:c __ t________ Hoi. No ...... __ T_P -_l_(_C_o_n_t_) __ _
Ar.a O •• llInotlon . .!..-_________ Coordino,.!.., ________________ Ground EI.voti0w." ____ D.pth To Ground Woter L.v.:..:.,.1 ___ _
Matllod of lIteovotlo" Approlilllota Dillla",lon, 0' Hola Dot .. 0' IIO."otloll Hola Loggad 8y ______ _
CLASII'ICATION
SYM.OL
LfTT!1'I IRAPHIC
SW
~-.. ---
ItIMARKS:
DEPTH
(,.UT)
;}
-
-
-
-
6 ----
~-7
-
-
--
---------
-
SIZE AND TYPE
OF
SAMPLE TAKEN
Bag (2)
S2
CL.ASSIFICATION AND DESCItIPTION OF MATERIAL
SAND: (contld)
Moist; 60-65% sand, well graded, fine to coarse;
15-20% gravel, gap graded, medium to fine; 10%-15%
silt; with occ. 21 lens of gravelly sand; medium
dense; gray brown.
Total Depth 7.0 1
Walls standing vertical
No groundwater encountered / Ground Surface
0 .. <IN"";,,,,,,,,,,,,,,'"'''''''' ,"' .. ","',"', "",r", .~Ash Layer 1--------------~OL
2-GW
--. -------3-SW -------
GW
5 . ...-. -----... ~ .,...-..-
, .. ----""",""-........ --__ SW
6-GP -) <.S:2. ~
---.,..."...
7-_--
8~--------------------------
GRAPHIC LOG OF WEST WALL
MAX.
SIZI
WEIGHT
RWB-403 1/2
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
Feature Aggregate Borrow Project Haines-Ska~ay Hydroelectric Project Hoi. Not....._T_P_-_2 ______ _
ArlO DniGnotlon Reservo; r site Coordinata. ~E 2358950 Sround flayotlop 665 :2 Dapth To Sround Woter Layel none
Metllod of Illoovotlo" hand dug ApprOllllllot. Dillllll.lon. of Hoi. see remarks Dote. 0' lacovotloll 9/4-9/5 Hoi. Loggod By DAY
CLUIIPlCATION
SYMIOL
L!:TTER ./tAPHIC
OL
ML
~-
SM
GW
DEPTH
(I'UT)
-
-
-
-
r
-
-
-
-
2-
-
-
--
3-
--
-
4-
--
-
5-
SIZE AND TYPE
OF
SAMPLE TAKEN
~ ........
Bag (2)
Sl
CLASSIFICATION AND DESCRIPTION OF MATERIAL
0.0-0.9 FOREST DUFF: Wet; organics; 5% roots with
~II layer of volcanic ash; soft; dark brown
~ TERRACE DEPOSITS ~
0.9-1.2 SILT: Wet; 80% silt; 20% fine sand ; medium
dense; brown.
1.2-4.5 SILTY SAND: Moist; 60%-65% sand,gap graded,
fine to medium ;40%-45% silt, with occasional lens
of fine to coarse sand; dens~ brown.
1---=-~----r/4.5-6.8 GRAVEL: Moist; 75%-85% gravel, well graded, "-Bag (2)
Sl fine to coarse; 20% sand well graded, fine to coarse;
5% cobbles up to 8" max; medium dense; gray brown.
RIMARKS: (contlnued)
Test Pit Dimension: 8~'L x 5~'W x 7'0
MAX.
SIZI
WEIGHT
RW8-403 2/2
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
I'.otur,~. __ A--.:9:::..:9::...r_e....::9~a_t_e_B_o_r_r_o_w ___ Proj.cu..t _H_a_i _ne_s_-_S_k_a....:9::...w_a...:::y_H..:.y_d_r_o_e_l_e_c_t_r_i c_P_r_o....;J::..· e_c_t _______ _ TP-2 (Cont) Hoi. NOIU.' _________ _
Area D .. llInatlon~ _________ Coordinot.~. ________________ Ground EI.v.tlo....," _____ D.l>tI' To Ground Wat.r L.v.:.:,I ___ _
Ibtllod of Ilo • .,.tlo" AI>P,Oll1ll8te Dillltneione of Halt Dot.. of IIClvetlon Holt LotlOld 8y
CLASllflCATION
SYMBOL
LHTl!:1I ellAPHIC
GW
DI!PTH
(fElT)
---
I
-
-
---
----
-.....;
---
-
SIZE AND TYPE
01'
SAMPLE: TAKEN
CLASSII'ICATION AND DESCIIIPTION 01' MATERIAL
GRAVEL (Continued)
Total Depth 6.8 1
Walls standing vertical
o _ No grou~ater -:ncountered ..LGrO~nd Surface
II""",,,,,, • .,,IIU """~'"I"';;II','11I , ...... sh Layer
1 ------'ML--~OL
-----1"'--'-"--'.---
? I --~
\ Approximate Bench Cut 3 .. __________ ---I
............ " SM
"-4 -
'\
"-
5 _
GW
6 .. "'-"""'--......
7 -~----~--~~--~------~---------------------------------IIIIIIAIIIKS:
GRAPHIC LOG OF SOUTH WALL
...... _-------------------------------------------_ ... _ .. _.
MAli.
Sill + 6"
WEIGHT
RW8·403 .. 1/?
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
Feotur. Aggregate Borrow Project Haines-Skagway Hydroel ectri c Project
Area 0 .. 19nolloll Reservo, r s 1 te CoordiRGt" ~ N2815800 E2358400 Ground EI.vation 655 £2
TP-3 Hoi. No ...... _____ --::::-::::-:::-:::--_
D.pt" To Grollnd Water Le.e;,;..1 _n.;...;;o.;...;;n..;;.e __
Hoi. l.olled By DAY "etllod of Ilcavetioll hand dug Approll",at. Dllllo"elo"o of Hola see rema rks Oat .. of 11I •• v.tlO" ]/4-9/5
CLASII'ICATION
SYMBOL DIPTH
t--......,r----I (FliT)
LHTIA '''APHIC
-OL -
-
-
SW 1-
----2_
--
-
-
3
GW -
-
-4_
--
-
5-
ItIMAItU:
Size; AND TYPE
OF
SAMPLE TAKEN
Bag (2)
Sl
0.0-0.6
wi th ~II
CLASSIFICATION AND DESC"IPTION OF MATERIAL
FOREST DUFF: Wet, organics; 5% roots;
volcanic ash layer; soft; dark brown.
TERRACE DEPOSITS
0.6-1.7 SAND: Moist; 85%-95% sand; well graded, fine
to coarse; 5-10% silt; medium dense; red brown.
V11.7-1.9 SILTY SAND: Moist; 50-65% sand; poorly grad~
pd finp arainpd' 35%-50% silt· medium dense' brown
1.9-6.4 SANDY GRAVEL: Moist; 60-65% gravel, well
graded, fine to coarse; 30-35% sand, well graded, finE
to coarse; 5% silt; 5% cobbles up to 8 11 maximum,
with some gravel iron stained; medium dense; gray
brown.
(continued)
Test Pit Dimension: 9~'L x 6'W x 6~'D
MAX.
SIZI
WEIGHT
+ s"
RW8-403 2/2
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
F.a'ur..:.._--LA ..... g~g~r'-'e .... g~a .... t...,e .......... B...,o"-'rl-r.....,O ..... W"--__ Praj.ct Haj nes-Skagway Hydroel ectri c Project Hoi. No. TP-3 (Cant)
Ar.o O .. lgllo'lolI"--_________ Coordillat":.. ________________ Groulld EI'yatio""" _____ D.pt" To Ground Water Leye . .;.I ___ _
M,tlld af l.oen,lolI Appra.hllGt' Di"""llon, of Holt Dot.. of 1.00.otI01l Hoi' L.aggt. By
CLASII'ICATION
SYMIOL
LITTfIt IItAPHIC
GW
.. IMARKS:
DIPTH
('IET)
:>
-
-
-
-
6-
-
-
-
7-
-
-
-
-
----
-
--
---
SIZE AND TYPE
OF
SAMPL.! TAKEN
CL.ASSIFICATION AND DESCItIPTION OF MATERIAL.
SANDY GRAVEL (Continued)
Total Depth 6.4 1
Walls standing vertical
No groundwater encountered
MAlt
SIZI
WEIGHT
RW8-403 1/2
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
Flotm Aggregate Borrow Projler Ha i nes-Skagway Hydroel ectri c Project
Aru O .. lgllotloll Reservo, r S1 te Coordi"otu ,;..;. N28160tJU 1:.2357900 GrOUlld £llvotio" 665 ±2
'''tllo' of Ilon.tloli hand dug Approallllotl OillllllSIoIIs 0' Holt see remarks D.t,. 0' Ilo ••• tlol\ 9/8
HOi' No. TP-4
Deptll To Groulld Watlr Llve;.;..1 _n_o_n_e __
Holt Lout. Bl DA Y
CLASIII'ICATION SIl( AND TYPE
SYMaOL D!PTH
1----~-__1 (I'IIT)
LETT!fI eflAPHIC SAMPLE TAKEN
01'
-
-
OL -
-
1--
SW ---
2-
-
GW -
--
3 -Bag (2) -Sl
-
-
4-
----
!=;
fIIMAflKS:
CLASSIFICATION AND OESCfllPTION OF MATERIAL
FOREST DUFF
0.0-0.7 SILTY SAND: Wet; 60% sand, poorly graded,
30-35% silt; 5% roots; soft; dark brown.
~ TERRACE DEPOSITS \
0.7-1.6 SAND: Moist; 85%-95% sand, well graded, fine
to coarse; 5%-15% silt; medium dense; red brown.
1.6-6.0 GRAVEL: Moist; 70-75% gravel well graded, fine
to coarse; 15-20% sand, well graded fine to coarse,
5% or less cobbles up to 8" maximum; less than 5%
silt; medium dense; gray brown.
(continued)
Test Pit Dimension: 8~'L x 6'W x 6'0
MAX.
Sill + e"
WEIGHT
e". I" 3", It" -It-
RW8-403 2/2
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
F.olur. aggregate Barrow .... oj.ct Haines-Skagway Hydroelectric project Hal. No, TP-4 (Cont)
Area 0.'19notlon"--__________ Coordlnol.,::.. _________________ (hound 11 .... '10""" _____ D'p'h To Ground Wot.r L..v.;.:,.I ___ _
Method of laoo .. ,loII Approallllate Dilll'''llonl of Hoi. Dot.. of IIO .. otlon Hoi. lOII.d BJ
CL.ASSIFICATION
SYMBOL.
L.!TTIUt .RAPHIC
GW
ItEMARKI:
DEPTH
(FIETl
5 -
-
-
-
6
-
-
-
--
-
-
--
-
-----
--
-
-
SIZE AND TYPE
OF
SAMPL.E TAKEN
,
CLASSIFICATION AN~ DESCRIPTION OF MATERIAL.
GRAVEL (cont1d)
Total Depth 6.0 1
Walls standing vertical
No groundwater encountered
•
MAX.
IIZI
WEIGHT
~----------------------------------------------------------------------------------------------------------~
RW8-403 ", 1/2
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
Hole N~-.....;5=---~ ____ _ future Aggregate Borrow Project Haines-Skagway Hydroelectric Project
Area Oe'llInatIO~V' c: ; to Coordl "" J:"?'{t;Annn Ground EI .... tlon ~~S +2
MMllod of IKCI."ItIOl'~ ApproKllllate Ol",enelon, of Hoi rna rkS Datil of EKOaYatloll
Depth To around Water Le.el 4, 3
Holl LOIIII' By DA Y
CLASllflCATION
SYMIOL
LETTEIt IItAPHIC
OL/sr~
St~
SW
SW
SM
ItIMARKS:
DEPTH
("IIT)
-
-
-
-
1-
-
-
-
-
2-
-
-
-
-
SIZE AND TYPE
OF
SAMPLE TAKEN
Bag (2)
SI
CLASSIFICATION AND OESCItIPTION OF MATERIAL
FOREST DUFF
0.0-1.1 SILTY SAND: Wet; 40-60% sand, poorly graded,
fine to medium; 25-30% silt; 15-20% organics; soft;
dark brown.
I t.KKALt. Utl-'U:::'ll:::'
1.1-1.6 SILTY SAND: Moist; 60-70% sand, well graded,
fine to coarse; 30-40% silt;med. dense; red brown
vl.6-2.1 SAND: Moist; 90-95% sand, well graded, fine---
to coars~%-10% silt; medium dense; brown
1fiT-3:1 Sand: Moist; 85%-95% sand, well graded, fine\
to coarse; 5-10% gravel, poorly sorted, fine to
medium; less than 5% silt; medium dense; gray.
3-,~ ----I
-Bag (2) 3.1-4.3 SILTY SAND: Wet; 65% sand, poorly graded, finE
to medium; 35% silt; occasional lens of coarse sand;
medium dense; gray -S2
--
4-
-~-~~-;----------------------------.--; -Bag (2)
-
-
r::
S3
4.3-6.0 SILT: Wet; 80-85% silt; J5-20% sand, poorly
graded, Tlne to medium; medium dense; gray
(continued)
Test Pit Dimension: 8~IL x 6~'W x 6 1 D
MAX.
SIZI + S-
WEI6HT
RWB-403
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
F.~ur,~.~~A_g_g_r_e~g_a_t_e~B_o_r_r_o_w~~_pr~.cat~_Ha_l_'n_e_s_-_S_k_a~g~w_a~y~H~y_d_r_o_e_l_ec_t_r_l_'c~P_r_o~j~e_c_t~~~~~~~ Hoi. N~TP-5 (Cont)
2/2
Are.. Onlgnotlon,"--_________ Coordinat.!.., _______________ ~ Ground EI.votio""'p'--____ D.pth To Ground Wat.r L.v •. ..;.I ___ ~
.. ,tllod 0' Ilo."tlo" Approal.at, Oillleneione 0' Holt Oat.. ot lacovotlon 14010 Loggod 8~
CLASSIFICATION
SYM'OL
Lf:TT(R .RAPHIC
RIMARKS:
O(PTH
(FUT)
5 -
-
-
-
6
-
-
--
-
-
-
---
---------
-;
SIZE AND TYPe:
OF
SAMPLE TAKEN
o -
CLASSIFICATION AND DUCRIPTION OF MATERIAL
SILT (cont'd)
Total Depth 6.0'
Walls standing vertical
Groundwater encountered
Ground Surface~
OLjML
at depth 4.5' during excavaticn
......,., .-r-___ -.-. ,......
1 --" --....... .",.... SM ____ .---------
_-----::iW __ ---
2 -_-----...-SW
4_---
ML
5
GRAPHIC LOG OF EAST WALL
MAX.
SIZI: + 6"
WE1GKT
~--------------------------------------------------~-------------------------------------------------~
RW8-403 1/2
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
Flaturl Aggregate Borrow Projlct Haines-Skagway Hydroelectric Project Hall NQ. TP-6
Aria D .. lgnatlon 8.eser:~Qjr: SHe Coordinal .. 8pprQ~ I ~ 281~~50. E 2359800 Ground Elevotlon ± 6 4 2 Dlpth To Ground Water LlVl1 5 9 1
M.thod of IICO.,.tloll band dllg Appro.llllot. Dilll.nlloni of Holt see remarks Dot.1 of 11 • ..,otloll 9,LZ Hoi. Logg.d Bl D~Y
CLASIII'ICATION SIZE AND TYPE WEIGHT
SYMIOL DEPTH OF CLASSIFICATION AND DESC"IPTION OF MATERIAL MAX.
(!'IIT) SIZE 3"-It" -It" LITTE" '''APHIC SAMPLE TAKEN + ," e"-3 11
-FOREST DUFF
-0.0-1.0 SANDY SILT: Wet; 40-60% sand, poorly graded,
SMjOL fine grai ned; 45-50% silt; 5-10% roots; soft ; dark -
-
1-TERRACE DEPOSITS -1.0-1.9 SILT: Very moist; 85-95% silt; 5-15% organics -medium dense; red brown ML -
-
2-1. 9-2.7 SANDY SILT: Very moist; 55-65% silt; 35-45%
-sand, poorly graded, fi ne; medium dense; gray
-S~1 -
-2.7-3.9 SAND: Moist; 95-100% sand, poorly graded,
3-fine to medium; 5% or less silt ; occasional lens of
-fine sand and silt ; medium dense; brown
-Bag (2 )
SP S1 -
-
4-85-95% silt; 5-10% sand, -3.9-4.9 SILT: Moist; poorly
graded; less than 5% gravel; medium dense; gray -
ML -Bag (2 )
-S2 (Conti nuedJ
5
"IMA"KS:
Test Pit Dimension: 8 1 L x 4 1 W x 6~'D
HWtS-~u,:) 2/2
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
F.o.ur.:.. __ A_g:.-g:.-r_e_g:.-a_t_e_B_o_r_r_o_w ____ prOj ..... ct_H_a_i_n_e_s_-_S_k_a_g_w_a_y_H_y_d_r_o_e_l_e_c_t_r_i_c_P_r_o_j_e_c_t ________ Hoi. NOIII.. __ T_, _P_' _6 ____ _
Area O .. llIna'lon"--_________ Coordinot.~. ________________ Ground EI.votio"'-n _____ D.p'" To Ground Wot.r L.v •. ..;..I ___ _
M.tlloll of Iloon,lon Approallllo" Oi •• nolona of Hoi. Oote, of IIO ••• tloll Hoi. Logg.d 8y
CLASIIPlCATION
SYM.OL
LfTTER IRAPHIC
sw
RIMARKS:
DEPTH
(fElT)
5 -
-
-
-
6-
-
-
---
-
-
----
-
-
-----
-
SIZ! AND TYPE
OF
SAMPLE TAKEN
CLASSIFICATION AND DESCRIPTION OF MATERIAL
4,9-6,5 SAND: Moist to wet; 90-95% sand, well graded,
fine to coarse; 5-10% silt; medium dense; brown to
5,5 ft; gray 5,5-6.5 1
,
Total Depth 6.5 1
Walls standing vertical
Groundwater encountered at depth 5,9 1 during excavati(n
•
MAX.
SIZI + SOl
WEIGHT
RWB-403 1/1
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
F.otur. Aggregate Borrow Proj.ct Haines-Skagway Hydroelectric Project Hoi. No. TP-7
Area O •• lgnatlan ReservQir Site Coordinat •• Approx. N 2814200,1 E 2360000 Ground EI ••• tio!l!,n!,...;6::;...4,;...:0:...,.,..,.,.,-_O.Pt"TOGrOundWDterL ••• :.:..,1....:2::...:.:.,:9~' __
MetIIolIo'laonotIOl'.!::!and d!,!g Approa .... t. Di .. tntlonto'Holt see remarKS Dot .. 0' loo"otlo" 917-918 H.I. LOII.d By DAY
CLASSII'ICATION SYMIOL
LI!TTUI .fIIAPHIC
ML/OL
SM
GW
fIIIMAI'IKI:
OIPTH (1'1iTl
-
-
-
-
1-
----
2-
-
-
-
-
3-
-
--
-
4---
-
-
SIZE AND TYPE
OF
SAMPLE TAKEN
CLASSIFICATION AND OESCfIIlPTION OF MATERIAL
FOREST DUFF/BOG
0.0-1.9 SILT: Wet; 80-85% silt; 5-10% sand, poorly
graded, ne grained; 5% roots and branches; soft;
dark brown
TERRACE DEPOSITS
1.9-2.5 SILTY SAND: Wet; 60-70% sand, poorly graded,
~fine to medium; 30-40% silt; medium dense; dark brow~
2.5-3.5 GRAVELLY SAND: Moist; 60-70% sand, well grade(,
fine to coarse; 30-40% gravel; iron stained and
cemented; very dense; red brown
Total Depth 3.5 1
Walls standing vertical
Groundwater encountered at depth 2.9 1 during excavati(n
Test Pit Dimension: 8 1 L x 5~IW x 3~ID
MAl(.
SIZI + ,"
WEIGHT
RW8-403
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
feature Aggregate Borrow Project Haines-Skagway Hydroelectric Project Hoi. NQ. Cut Bank 1
Area Designation Reservoir site Coordinate. N2816000~ E2359l00 Ground EI'VO:~ Depth To Ground Wattr Leve'
Metllcd of IloeCIVo,loft none Approlho'" Di"'.lIIlon. cf Hoi, :ee rema rK:s Doto. of I:Io.tvot10 Holt LoUt. 8y DAY
CLASI'I'ICATION SIl[ AND TYPE WEIGHT
SYMaOL DEPTH Of CLASSIFICATION AND DESCIUPTION 01' MATERIAL MAX.
(FUT) SIZE + S-6".3" 3". It" _ I'r N
LI!TTEIt '''APHIC SAMPLE TAKEN
TERRACE DEPOSITS -0.0-1.0 SILTY SAND: Wet; 60-70% sand, fine grained
SM -30-35% s i1 t· 5% oraan; CS· mpd dpnsP' arav
-1.0-3.5 SANDY GRAVEL: Mo;st; 55-60% gravel, \AJe 11
-graded, fine to coarse; 30-35% sand, well graded, fin
2-to coarse; 5% or less silt; medium dense; gray.
Bag (2) -Sl GW -
-
-Total Depth 3.5'
4-
-
-/ __ ~ uPPEr:<-""'-""'!<',:Af P.
'¥" -( f;;/C:.:(
-
-"'KO""'\"' '::'\)'P'" "/-/ \~
-
-f ~ -? ri :/
-f.J ,'1 -~ \J
---:; u-r 'I?MiK 'C'\<El~\ --
-
"IMUKS: Sampling and logging were completed on existing creek bank.
All slopewash was removed; locations of sample and contacts
are relative to top of lower terrace.
nng-"9V~ • 1/2
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
Flaturl Aggregate Borrow Projlct Hai nes-Skagway Hydroel ectri c Project
Aria O .. llInatlon ReSerV01 r Sl te Coordina! .. ~ N2815500 E2359400 Graund Ellvation 638 £2
Nltllad af laeOYltla" none Approahllate Oillllnilonl af Holl see remarks Dot .. of laOlyotlOft 9/8781
Hall Na ...... __ C_u_t _B_a_n_k_2 ___ _
Olpth To Ground Water Llvl;:,.1 ___ _
CLASII .. ICATION
SYMBOL OIPTH
(FliT)
LETT!1t IItAPHIC
-
-
9·1 -
-
2-
-
-
-
-
4-
-
-
--
6 ---
-
S----
-
In
ItINAItKS:
SIZE AND TYPE
OF
SAMPLE TAKEN
Bag (2 )
Sl
CLASSIFICATION AND OESCItIPTION OF MATERIAL
TERRACE DEPOSITS
0.0-3.0 SILTY SAND: Moist; 60-65% sand, poorly graded
fine to medium; 30-40% silt; 5% or less organics;
with ~II layer of volcanic ash; medium dense; gray
brown.
3.0-4.8~: M01St; 85-95% sand, poorly graded, f1ne
to medium;-5% silt; occasional lens of gravelly sand;
medium dense; brown.
4.8-12.5 SANDY GRAVEL: Moist; 60-65% gravel well
graded, fine to coarse; 30-40% sand, well graded, finE
to coarse; 5% or less silt; occasional cobble
8" maximum; medium dense; gray brown.
(continued)
MAX.
SIZI
Hale LOOllld By DAY
WEIGHT
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
... o,ur..;.. __ A....:g=...;:g:...r_e...;:g:...a_t_e_B_o_r_r_o_w ___ Prol.c ..... t __ H_a_i_n_e_s -_S_k_a....;g::..w_a...:::Y_H...:::Y_d_r_o_e_l_e_c_t_r_i _c_P_ro....;.J=-· e_c_t _______ Hoi. Ho .... _C_u_t_B_a_n_k_2 ___ _
Aru 0 •• 19nollon:.:..-_________ Coordinot.s:.. ________________ Ground EI ••• tiOw.Il _____ D.ptll To Ground Wat.r L ••• :..;.I ___ _
MotllOd of 11I00.,ot101i Approllilloto Di",o"olo"o of Hoi. Dot.. of ':a •• ".tlo" Hoi. Loggld B~
CLASII'ICATION SIZE AHD TYPE
CLASSIFICATION AND DESCIUPTION Of MATERIAL SYMIOL DEPTH OF
<"UT)
LETTER .RAPHIC SAMPLE TAKEN
SANDY GRAVEL (Continued) 10 -
-
-
-
12-
-
-Total Depth 12.5 1
-
-
-
-, "~1.~ \--~: r: "'--
--{!ii(' I ~
-12.5 /W, ~--
--
-
-
-
-
-
--
REMARKS: Sampling and logging were completed on existing creek bank.
All slopewash was removed; locations of samples and contacts
are relative to top of terrace.
IIIAX.
SIZI + 8~
WEIGHT
~--------~,~.----------------------------------------~~----------------------------------------------~
" R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
f.ature Aggregate Borrow Project Haines-Skagway Hydroelectric Project Hole MQ. Cut Bank 3
Area D .. ionation ReSerVOlr s1te Coordinat .. ,... N28I~550 E2359650 Ground Elevation Depth To Ground Wat.r Level
M.,IIo4I of laaevetloll nQne Approallllote Ollllel\llon. of Holt see remarKs Dote. of lalltv.tlOI! 9Z8Z81 Hole Lotted 8): DA Y
CLAS'II'ICATIOM SIZE AMO TYPE WEIGHT
SYMBOL OEPTH OF CLASSIFICATIOM ANO OESCItIPTIOM OF MATERIAL MAX.
(I'IIT) SIZI 3"~ It" -It" LETTEIt IItAPHIC SAMPLE TAKEM + ." .", ;s"
0.0-0.6 FOREST DUFF: Moist; 100% organics; with 1 II '2 -volcanic ash laver' soft· dark hrown -0.6-8.0 SAND AND GRAVEL: Moist; 50-55% gravel, well
-graded, fine to coarse; 45-50% sand, well graded fine
-to coarse; less than 5% silt; occasional cobbl e to
2-8" max; medium dense; gray brown.
-
-
--
'f
-Bag(2) ~ ,D? (A::: 'Te'l<'VAUE"
-Sl I/'~' -S' '~/ GRCen)>lv $\)1"'.1"",(""
-L _\1 __
6-~
-CU1 BANK sKeTc..t4 -
-
-
Total Deoth 8 0 1
(j --
--
1()
ItIMAItKS: Sampllng and logg1ng were completed on eXlstlng creek bank.
All slopewash was removed; locations of samples and contacts
are relative to top of terrace.
RWB-403
R. W. Beck and Associates
LOG OF TEST PIT OR AUGER HOLE
Flaturl Aggregate Borrow Projlct Hai nes-Skagway Hydroel ectri c Project
Aria O .. lgnotlon reSerVOl r s 1 te Coord!".".. '"" N2814200, E2360300 Ground Ellvatioll 630 ±2
Hall No ..... __ C_u_t_B __ a_n_k _4-=----__ _
M.thod o'"lacl.ltlo" -Appro.l.at. Dim.nslons of Hoi. see remarks Oat •• of II0lviti01l 9/8781
CLASB'P'ICATION
SYMBOL
L!TTE" ."APliIC
GW
SW
D[PTH
(fliT)
-
-
-
-
2-
-
-
-
-
4-
-
-
--
6-
---
8-
-
SIZ! AND TYPE
Of
SAMPLE TAKEN
Bag (2)
Sl
= Bag (2)
~ __ ~ __ ~JO S2
CLASSifiCATION AND DESC"IPTION Of MATERIAL
TERRACE DEPOSITS
0.0-2.5 SANDY SILT: Moist; 60-65% silt; 30-35% sand,
poorly graded, fine grained; 5% or less organics; wit
~" volcanic ash layer; medium dense;gray
1~2.5-6.4 GRAVEL: Moist; 65-70% gravel, well graded '\
fine to coarse; 25-35% sand well graded, fine to
coarse; 5% or less silt; medium dense; red brown
to brown.
6.4-10.0 SAND: ~'oist; 85-95% sand, well qraded, fine\
to coarse; 5% or less gravel, fine grained; 5% or
less silt; medium dense; gray.
f .
10' ~X,-,,---~
Total depth 10.0 1 CUT SANK ?KETU~
fIIIMAfIIKS: Sampling and logging were completed on existing reek bank.
All slopewash was removed, exact locations of samples and contacts
are relative to top of terrace.
MAX.
SIZ[
Otpt" To Ground Wattr Ltvt:.;..' ___ _
Hole Loggtd By DAY
WEIGHT
+ s"
•
Z660l
Q TP-1
r-I ---~650 Ot-\MSIFl--------
UJ 4600 _-
~ 640
ex:
0..
'-
190,000 OHMS/FT
TP-2
I
3,700 OHMS/FT --------
74,000 OHMS 1FT
TP-3
I
TP-4 TP-5 I 1,430 OHMS/FT I 3,200 OHMS/Fr
-------4,9000HMS/FT __ ------------
2.100 OHMS/FT
58,000 OHMS 1FT
94,000 OHMS 1FT
0.. ---------------------------------------------------< o OHMS/FT 18.000 OHMS/FT
630
Z o
r-< >
650
~ 640
UJ
UJ r-<
::E
x 630
o ex:
0..
0.. <
620
TP-6
I ~1.500 OHMS/FT TP-7 ~
I
1,000 OHMS/FT --L_--=:-::::;:; - -55,000 OHMS/FT ~ ----
40,000 OHMS 1FT
-----------1,000 OHMS/FT
o OHMS/FT
Thil5 drawing il5 reduced to 6 of original
----o OHMS/FT o OHMS/FT
EARTH RESISTIVITY SOUNDING PROFILES
Alaska Power Authority
HAINES-SKAGWA Y REGION -FEASIBILITY STUDY
WEST CREEK PROJECT
for R.W. Beck and Associates, Inc.
@ ConverseWardDavlsDlxon Gooteohnlc., Con.ull.no
Scale NOTED
Date FEB 1982
Prepared by BH
CPB
WSB
Project No.
81-5165
Drawing No.
B-1
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RESISTIVITY SOUNDING 1
aska Power
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(i Converse Consultants
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RESISTIVITY SOUNDING 2
Alaska Power Authority
CREEK PROJECT
for R W. Beck and Associates, Inc.
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Alaska Power Authority
wEST CREEK PROJECT
for R.W. Beck and Associates, Inc .
Converse Consultants
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Alaska Power Authority
WEST CREEK PROJECT
for R.W. Beck and Associates, Inc.
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PrOject No.
81-5165
Drawing No.
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Alaska Power Authority
WEST CREEK PROJECT
for R.W. Beck and Associates, Inc.
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Alaska Power Authori
WEST CREEK PROJ
for R.W. Beck and Associates, Inc.
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aska Power Authority
T CREEK PROJECT
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Drawing No_
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APPENDIX C
ROCK TEST! NG
C.1 GENERAL
A laboratory testing program was performed on selected rock core samples
obtained during the phase II geotechnical investigation of the West
Creek Hydroelectric Project. The purposes of this testing program were
twofold: to identify the rock types and to establish the engineering
properties of the principal rock. Tests to determine engineering prop-
erties consisted of density! specific gravity and uniaxial unconfined
compression. Petrographic analyses on selected rock core samples were
conducted for i dent ifi cat ion purposes; procedures and results are pre-
sented in this Appendix.
C.2 ENGINEERING PROPERTIES
Engineering properties were determined for selected rock core samples
obtained from borings at the dam site. A total of 15 specimens were
selected for tests from bori ngs DH 102 through DH 107. Each specimen
was prepared by cutting and surface grinding so that the specimen ends
were flat to within a O.004-inch tolerance. All specimens were weighed
and measured to determine unit density and specific gravity by ASTM C-97
Method.
Nine specimens were selected for uniaxial unconfined compression tests.
Foil grid resistance strain gauges were cemented to each specimen to
measure radial and axial strain during loading. Axial loading of speci-
mens was continued until ultimate failure occurred with continuous moni-
toring of axial and radial strain measurements. Testing and data reduc-
tion for strength! Young's Modulus (tangent and secant) and Poisson's
Ratio! were conducted in accordance with ASTM 31484-79. The rock tests
were conducted at the University of Washington Civil Engineering struc-
tural testing laboratory in Seattle, Washington on January 18, 1982.
Converse Consultants. Inc.
C-2
The equipment utilized for the tests included a Baldwin 350,000-pound
load frame, a BLH Model 1200 B digital strain indicator, and a BLH Model
1225 switching and balancing unit.
The results of the individual test are shown on Drawing Nos. C-l through
C-9; a summary of the test results are presented in Table C-l.
In addition, 13 specimens from boring DH 108 were tested for unconfined
strength and specific gravity by the Robbins Company of Kent, Washing-
ton. The results are summarized on Table C-l.
The uniaxial compressive strength tests which were completed by Converse
Consultants indicate higher ultimate strengths than uniaxial compressive
strength tests completed by the Robbins Company. Visual inspection of
rock specimens tested by the Robbins Company indicated good failures
planes developed. The specimens whi ch the Robbi n Company tested were
taken from NX wireline core (1.88 inch diameter) and were recored to a
one-inch diameter. Specimens were cut to a 2 to 1 height to diameter
ratio and the ends were surface-ground flat. A Riehle 200,000 pound
load frame was utilized to produce axial load to failure.
It is of our opi ni on the lower compressi ve strengths i ndi cated by the
Robbins tests are due to the following:
1. The smaller diameter of the rock core specimen (ASTM Method
D3148-79 states a diameter of not less than NX wireline core
size should be used).
2. The grain··size of the rock type, (ASTM Method D3148-79 indi-
cates that it is desirable that the diameter of rock compres-
sions be at least ten times the diameter of the largest min-
eral grain.)
The values given by the Robbins Company should be considered to be very
conservative for ultimate strengths.
Converse Consultants, Inc.
C-3
C.2 PETROGRAPHY
Petrographic analyses were performed on selected rock core samples ob-
ta i ned from bori ngs number DH 103, DH 104, DH 107 and DH 108. Petro-
graphic descriptions of the thin sections examined are enclosed as Draw-
ings C-10 through C-1S.
The specific objectives of the petrographic analyses were as follows:
1. To verify and supplement field identification of lithologies
and rock affinities.
2. To provide additional data on the mineralogical and micro-
structural characteristics of selected rock samples recovered
from drill cores.
Thin sections were prepared by Pacific Petrographic Thin Section Labora-
tory, Spokane. Washington. Rock samples were slabbed, trimmed and the
resulting rock chip was mounted on standard 27 by 46 mm glass slides.
The mounted rock chip was then ground to a uniform thickness of 0.03 mm.
polished and covered with a thin cover glass. The thin sections were
routinely stained with sodium cobaltnitrate to aid in the identifica-
tion of potash feldspar.
A petrographic polarizing microscope was utilized to examine the petro-
graphi c sect ions. The petrographi c mi croscope is essent i ally a common
compound microscope modified for observation of the optical properties
of non-opaque anisotropic minerals. It includes a rotating stage, an
upper polarizer (commonly known as the analyzer) and a lower polarizer.
Other accessories include an Amici-Bertrand lens, a condenser, and
several varieties of compensating plates used in making optical deter-
minations.
Systemat i c petrographic descri pt ions attached to thi s appendi x i ncl ude
rock name, approximate percentage of nineral constituents (visual-
ly estimated), texture, grain size, structural features and a brief
Converse Consultants, Inc.
C-4
descri pt ion or character; zat ion of the rock. Spec; al i zed petrographi c
nomenclature is used to describe various features useful in distinguish-
ing rock types. Detailed treatment of this subject may be obtained from
any of numerous reference texts (W;lliams~ et al. 1954).
Con'~erse Consultants, Inc.
TABLE C-1
ROCK TEST SUMMARY
Young' s I\bd~ I us
Rock(\) Test (2)
psi x 10
Pol SS01' s (5) Boring Sps::imen Depth DensIty Sps::lflc Ultlmrte Secant (4) Project Feeture tb. tb. (feet) .!le!. .!le!. (pef) Gravity Strength Tan!!!!t(3) Ratio
Left Abutrrent 102 102-1 11.0 -11.5 GJ LC 166.1 2.62 16,210 5.02 4.21 0.24
left Abutment 102 102-2 tD.l -20.5 GJ DEN 167.4 2.63
Left Abutrrent 102 102-3 41.0 -41.45 AID DEN 161.4 2.53
left Abutment 102 PET-l02 41.45-41.5 AID PET
Left Abutrrent 103 PET-103 7.5 -7.6 GJ PET
left Abutment 103 103-1 7.6 -8.0 GJ DEN 166.4 2.59
Left Abutrrent 103 103-2 8.0 -8.4 GJ LC 167.6 2.62 20,320(6) 5.80 3.98 0.20
left Abutment 103 103-3 14.3 -14.7 GJ LC Hi8.1 2.63 4,899
Left Abutrrent 104 104-1 21.3 -21.7 GJ LC 167.1 2.62 16,350 5.52 4.30 0.25
leftAbutment 104 104-3 25.3 -25.7 W DEN 167.2 2.62
Left Abutrrent 104 104-4 34.7 -35.1 GJ LC 167.7 2.63 15,920 5.98 5.98 0.12
Left Abutrrent 104 PET-l04-1 35.5 -35.6 KD PET
Left Abutrrent 104 PET-l04-2 140.0 -140.5 fGJ PET
Right Abutment 105 105-1 12.7 -13.1 GJ DEN 166.3 2.61
Right Abutrrent 105 105-2 20.5 -20.9 GJ LC 167.4 2.62 19,920 7.22 4.98 0.27
Right Abutment 105 105-3 20.9 -21.25 W LC 167.1 2.62 12,430 6.14 6.06 0.28
Intake Structure 106 106-1 5.7 -6.0 GJ DEN 165.8 2.61
Intake Structure 106 106-3 14.35-14.6 W LC 167.1 2.62 10,000 2.23 2.56 0.17
Rl ght Abutrrent 107 107-1 48.6 -48.9 AGJ LC 166.0 2.61 20,800 7.83 6.93 0.22
Right Abutment 107 PET-l07 48.9 -49.1 KD PET
Surge Tank Ire PET-Ire 373.0 -373.1 fGJ PET
Fol 101/1 ng data coop I erred by The Robb 1 ns Corrpany
Surge Tank Ire 3659 63.0 -64.2 GJ LC 2.67 10,190
Surge Tank 108 3659 63.0 -64.2 LC 2.67 12,730
Surge Tank Ire 3660 209.2 -210.0 GJ LC 2.67 8,910
Surge Tank 108 3660 209.2 -210.0 GJ LC 2.67 14,010
Surge Tank 108 3660 209.2 -210.0 GJ LC 2.67 8,910
Surge Tank 108 3661 375.0 -376.2 KD LC 2.4 8,275
Surge Tank Ire 3661 375.0 -376.2 fGJ LC 2.4 8,275
Surge Tank 108 3661 375.0 -376.2 KD LC 2.4 7,640
Surge Tank Ire 3661' 375.0 -376.2 fGJ LC 2.4 6,365
Surge Tank 108 3662 486.5 -487.7 W LC 2.68 7,640
Surge Tank Ire 3662 486.5 -487.7 GJ LC 2.68 12,730
Surge Tank 108 3662 486.5 -487.7 GJ LC 2.68 12,730
Surge Tank 108 3662 486.5 -487.7 GJ LC 2.68 15,280
(1)Rock Type: GO = granodiorIte; AGJ = altered granodiorite; AID = andesite dike.
(2)Test Type: LC = uniaxial unconfined coopressla'l test; DEN = density and specific gravity tests; PET = petrology-perrrographic analysis
(3)Tangent I\bdulus based on rrost Iinecr portion of stress-straln curve Irt 40 percent of the ultlmrte axial stress.
(4)Secant Modulus from zero stress to 40 percent of ultimate axial stress.
(5)PolsS01'S Ratio calculated fran tangent portion of axial and radial stress-straln curves.
(6)Ultlmate strength 1011 due to failure along pre-exlstlng fracture, no Young's Modulus or Poisson's Rlrtlo calculated.
RADIAL STRAIN
· .-· «0 · Q.
· tI)
tI) w a:
I-
tI)
W
(!)
8 < a: w > 6 <
4
1000
STRESS
AXIAL STRAIN -1000 -1500 -2000 -2500 -3000
SAMPLE DESCRIPTION
AVERAGE AVERAGE AIR DRY UNIT
.' ; : DIAIiETERUN •• LENGTH UN.. WT. (p.c.f.)
1. 88 4.43 166.1
TEST RESULTS
... i ULTIIiATE YOUNG'S IIODULUS,
---+ .. .J--,----"..~ i COIIPRESSIVE ,,-:::-:-~P~._ •• _I.-.-X_1;;..;O;;..e __ ~
r I STREHGTH(p.s.Ur TANGENT SECANT
16 210 5.02 4.21
-500 -1000 -1500
-3500
SPECIFIC
GRAVITY
2.62
POISSON'S
RATIO
0.24
AVERAGE STRAIN, Inches/inch X 10-6
REIIARKS: Parti a 1 upper and lower end conI)
developed. Conjugate shear planes at 70 .
Minor lateral tensile splits observed.
Sample No. 102-1
ROCK CORE UNCONFINED COMPRESSION TEST
Alaska Power Authority
WEST CREEK PROJECT
for R.W. Beck and Associates, Inc.
Converse Consultants
Project No.
81-5165
C-1
18
16
· .-· 14 co · Co ..
rJ) 12 rJ)
W a:
I-10 rJ)
W
" 8 <C a:
W
> 6 <C
4
STRESS -STRAIN CURVES
I .
I
AVERAGE
. DIAMETER UN.)
1.88.
AVERAGE AIR DRY UNIT
LENGTH (IN.) WT. (p.c.f.,
4.47 167.6
TEST RESULTS
SPECIFIC
GRAVITY
2.62
2
ULTIMATE YOUNG'S MODULUS,
-~~~-+-+~~~"---'-1--~+';"~' '-!-·-h-~,-.. +-l--l-;-f-i-f--=:~~~f~+·-;·----+.I'·+··i-+-1f--·""""c~-lI COMPRESSIVE p ••• I. X 1 0 8 POISSON'S
RATIO
a 1000 500
Sample No. 103-2
t STRENGTHfp.s.Q TANGENT SECANT
20,320 5.80 3.98 0.20
-500 -1000 -1500
A VERAGE STRAIN, Inches/inch X 10-6
REMARKS: Upper endocone eve ope. ~ onJuga e
shear planes at 75. Lateral tensile splits
observed.
ROCK CORE UNCONFINED COMPRESSION TEST
Alaska Power Authority
WEST CREEK PRUJECT
for R.W. Beck and Associates, Inc.
Converse ConsL!ltants .
Project No~
8 5165
Drawing No.
C-2
· .-· (I) · a. ..
(J)
(J) w a::
t-
(J)
W
Cl « a:: w > «
200
Sample No. 10 3-3
STRESS -STRAIN CURVES
AXIAL STRAIN -400 -500 -600 -700 -800 -900 -1000 -1100 -1200 -1300 -1400 -1500
AVERAGE
DIAMETER (IN.
1.88
I l ,
SAMPLE DESCRIPTION
AVERAGE AIR DRY UNIT
LENGTH (IN.) WT. (p.c.t.,
4.40 168.1
TEST RESULTS
YOUNG'S MODULUS.
p.8.1. X 10.
TANGENT SECANT
* *
SPECIFIC
GRAVITY
2.63
POISSON'S
RATIO
*
100 0 -100 -200 -300 -400 -500 -600
A VERAGE STRAIN, Inches/inch X 10-6
REMARKS: Low ultimate streng~h controlled by
closed calcite fracture at 65. Radial gauge
sheared at 900 psi.
*Youngs Modulus and Poisson1s Ratio not calculated due to nature of curve.
ROCK CORE UNCONFINED COMPRESSION TEST
Alaska Power Authority
WEST CREEK PROJECT
for R.W. Beck and Associates, Inc.
Converse Consultants
Project No.
81-5165
Drawing No.
C-3
STRESS -STRAIN CURVES
-1500 -2000 -2500 -3000 -3500 AXIAL STRAIN -1000
20~~~--~~~--~~~~~~~~~-r~~----~--~--~---T--~--------~--~--------
16
· · rn · Q. -en 12 en
W a: .... 10 en
w
C!J 8 « ---
a: w > 6 . -. «
4
2
1800 500
Sample No. 104 -1
SAMPLE DESCRIPTION
AVERAGE AVERAGE AIR DRY UNIT SPECIFIC
. .: DIAMETERCIN.' LENGTH (IN.) .T. (p.e.f.) GRAYITY
1.88 4.66 167.1
TEST RESULTS
UL T.MATE YOUNG'S MODULUS,
~I-~---:-"-'+'-----+----+~~-+----~' ---+-,.~-., ... -.".. ".~.-~-+--.~;.~ i COMPRESSIVE t--__ p;...._ •. _I ..... X_1.;;.08 __ ---1 POISSON'S
RATIO
•• 1 STRENG11I ....... TANGENT SECANT . . j~---~--~~~~-+~~~~~------~
t 16 350 5. 52 4. 30 0.25
-500 -1000 -1500
AVERAGE STRAIN, Inches/inch X 10-6
REMARKS: Upper end cone and partla ower en 0
cone developed. Conjugate shear planes at 85
Lateral tensile splits observed.
ROCK CORE UNCONFINED COMPRESSION fEST
Alaska Power Authority
WEST CREEK PROJECT
for R.W. Beck and Associates, Inc.
Converse Consultants
Project No.
81-5165
Drawing No
C-4
· .-· • · Q. .. en en w a:
t-en
w
C!J « a: w
> «
14
12
1
-------------------s~T~R~ES--S----S-TRAIN·~C~U=R~V=E~S------------------------------~
RADIAL STRAIN AXIAL STRAIN -800 -1000 -1200 -1400 -1600 -1800 -2000 -2200 -2400 -2600 -2800 -3000
AVERAGE
,. DIAMETER UN.)
.88
. ;
---~ .
SAMPLE DESCRIPTION
AVERAGE AIR DRV UNIT
LENGTH UN.) WT. (p.e.f.'
4.47 167.7
TEST RESULTS
SPECIFIC
GRAVITV
2.63
; .. j ~ ~UL~T=I~M~A~T~E~'--=VO~U~N~G~'S~M~O~D~U~L~U7S-,--r-P-O-I-S-S-O-N-'S~
-++-"--~ .. -' I COMPRESSIVE p ••. '. X 10 •
. ...• ~ STRENGTH(p.s..Q~T~A~N~G:-:::E:-N~T--'r--~S~E~C-A-N-T--f RATIO
15,920 5.98 5.98 0.12
800 600 400 200 0 -200 -400 -600 -800 -1000 -1200 REMARKS: Failure along vertical partially
altered fracture. Partial upper and lower end
cone developed. Minor lateral splits observed. A VERAGE STRAIN, Inches/inch X 10-6
*Radial strain gauge failure
Sample No. _1_04_-_4 __
ROCK CORE UNCONFINED COMPRESSION TEST
Alaska Power Authority
WEST CREEK PROJECT
Project No.
81-5165
for R.W. Beck and Associates, Inc.
Converse Consultants
Drawing No.
C-5
· .-· fI) · a. .. en en w a:
I-en
w
<!J « a: w > «
2
500
STRESS -STRAIN CURVES
-1500
-500 -1000 -1500
-2000
AVERAGE
DIAMETER ( IN.)
1.88'
2500 -3000
SAMPLE DESCRIPTION
AVERAGE AIR DRY UNIT
LENGTH (IN.' WT. (p.e.f.'
4.32 167.4
TEST RESULTS
UL Till ATE YOUNG"S IIODULUS.
COIIPRESSIVE p.s.l. X 10.
STRENGTH(p.s.Q TANGENT SECANT
19 920 7.22 4.98
-3500
SPECIFIC
GRAVITY
2.62
POISSON'S
RATIO
0.27
AVERAGE STRAIN, Inches/inch X 10-6
REIIARKS: Parti a 1 upper and lower end cOBe
developed. Conjugate shear planes at 80 .
Lateral tensile splits observed.
Sample No. _1_0_5_-2 __
ROCK CORE UNCONFINED COMPRESSION TEST--
Alaska Power Authority
WEST CREEK PROJECT
Project No.
81-5165
for RoW. Beck and Associates, Inc.
----------------------~----------------------------------~~~-----~ Converse Consultants C-6
20
18
16
· .-· (I) 14 · Q.
· f/) 12 f/)
W a:
t-lD f/)
w
e" 8 <C a:
W > 6 <C
4
2
0
STRESS -STRA N CURVES
AXIAL STRAIN -800 -1000 -1200 -1400 -1600 -1800 -2000 -2200 -2400 -2600 -2800 -3000
, . ' ,
~, ,
H--J-+Hr-;--r-t--r-t-r-t-t-+-----+H-tT-t--r----:--tr:-H-j--t-r-M-+-;-n--t~~~~--:--+ :+--t-~-+--~~-----+-j~~~~~~.~
, AVERAGE
; i DIAMETER UN.
1.88
I
I
SAMPLE DESCRIPTION
AVERAGE AIR DRY UNIT
LENGTH (IN.) WT. (p.e.f.'
4.29 167.1
TEST RESULTS
SPECIFIC
GRAVITY
2.62
': . : ULTIMATE YOUNG'S MODULUS.
1--'--.-... ~+..Ll·+·+·-t .. "~_·~_-' .-~--i.-; .. ~__I__' ...... ,--_ .... f.-... ,.-, .. d._<L.j_'___+_-+__'__'_______,__j.-..... +--, -i-.L. "-7-'-+~ --;--. COMPRESSIVE t----=p;.;;.. S,;;.;.:.:.:'.;..,;X;.:....,:1;..;:o;,..6 __ --I
," ; 'I STRENGTH(p.sJ) TANGENT SECANT
POISSON'S
RATIO
.. +1 12 430 6.14 6.06 0.28
600 400 200 0 -200 -400 -600 -800 -1000 -1200 REMARKS: Partial upper and lower end cone
AVERAGE STRAIN, Inches/inch X 10-6 developed. Conjugate shear planes at 75°.
Lateral tensile splits observed.
NOTE: Readings above 7200 psi not recorded due to failure of foil strain gauge.
--------~~------~--~--~~~---------------ROCK CORE UNCONFINED COMPRESSION TEST 105-3 Samp~No. ______ __ Alaska Power Authority
WEST CREEK PROJECT
Project No,
81-5165
for R.W. Beck and Associates, Inc.
Drawing No.
Converse Consultants C-7
RADIAL STRAIN
10
9
8
.-. co 7 .
Q.
t/) 6 t/) w a:
l-S t/)
W
CJ 4 « a: w > ? « ..;
2
1
0
1000 500
STRESS -STRAIN CURVES
AXIAL STRAIN -1000 -1500 -2000
AYERAGE
DIAMETER(IN.)
1.88
2500 -3000
AYERAGE AIR DRY UNIT
LENGTH (IN.) WT. (p.e.f.'
4.28 167.1
TEST RESULTS
ULTIMATE YOUNG'S MODULUS.
I COMPRESSIVE t--...;.P......; •• ......;.I...;., ...... X;.....;..10.:...8 __ --I ; '. ' ! STRENGTH(p..s.Q TANGENT SECANT
10 090 2.23 2.56
-500 ~1000 -1500
-3500
SPECIFIC
GRAYITY
2.61
POISSON'S
RATIO
0.17
AVERAGE STRAIN, Inches/inch X 10-6
REMARKS: Partial upper and lower end cone
developed. Conjugate shear planes at 65 0
Lateral tensile splits observed.
Sample No. 106-3
*Radial strain gauge failure
ROCK CORE UNCONFINED COMPRESSiON TEST
Alaska Power Authority
WEST CREEK PROJECT
for R.W. Beck and Associates, Inc.
Converse Consultants
Project No.
81-5165
Drawing No.
C-8
'--------------------s-T-R-E-s-s----s--TRAlN~C~U7.R~V7.E=S~------------------~~------~
20
18
16
· .-· 14 ., · Q.
· CIJ 12 i
CIJ w a:
I-10 CIJ
W
Cl 8 ..:(
a: w
> 6 ..:(
4
• t
AVERAGE
,", DIAMETER UN.)
1. 88
SAMPLE DESCRIPTION
AVERAGE AIR DRY UNIT
LENGTH (IN.) WT. (p.c.'.)
4.36 166.0
TEST RESULTS
ULTIMATE YOUNG'S MODULUS.
COMPRESSIVE p ••• '. X 10.
; '; ! STRENGTH(p.s,Q TANGENT SECANT
SPECIFIC
GRAVITY
POISSON'S
RATIO
. : : ,I " I 20,800 7.83 6.93 0.22 O~~~~~--~~~~~--~~~~~~~~~~~~~~~~~~~~~~~~~--~~~ 200 0 -200 -400 -600 -800 -1000 -1200 REMARKS: Sampl e parti ally a tere atera y. 600 400
Sample No. 10 7 -1
AVERAGE STRAIN, Inches/inch X 10-6 Upper end cose developed. Conjugate shear
planes at 70. Lateral tensile splits observed.
ROCK CORE UNCONFINED COMPRESSION TEST
Alaska Power Autnori1:.Y
WEST CREEK P~OJECT
for K.W. 8eck and Associates, Inc.
Converse Consultants
Project No.
81-5165
Drawing No.
C-g
PETROGRAPHIC REPORT
SHEET_1_ OF_1
Project Name: Haines-Skagway Hydroelectric Project J Job
I
No.: 81-5165-16
Date Sampled: Analysis By: S.M. Testa Date: March 1, 1982
Sample No.: Pet-DH 102 Source: Boring 102 at a depth of 41.5 feet.
Location: Left Abutment
Megascopic Classification: ANDESITE BASALT
PETROGRAPHIC ANALYSIS:
ROCK NAME: ANDESITE BASALT
MINERAL CONSTITUENTS:
Primary Minerals Secondary Minerals
Feldspar Ca 1 cite m
Plagioclase 85 Seri cite tr
Potash Fe'l dspar 10 Chlorite tr
Quartz tr
Opaque Minerals tr
DESCRIPTION:
Massive microcrystal 1 ine rock characterized by holocrystalline intersertal
texture. Plagioclase forms a network of randomly ori ented 1 aths and has an
anorthite content of about An44, that fa 11 i ng with; n the range of andesine.
Interstices are fill ed with a combination of potassium feldspar and opaque
minerals, and secondary minerals which include calcite and chlorite. Opaque
minerals occur as randomly dispersed equant grai ns and include in part pyrite.
Sericitization and chloritization is nominal. A thin irregular veinlet apparent
on a port ion of the section is fi 11 ed chi efly with calcite and subordi nate
chlorite, potash feldspar and plagioclase.
note: m = minor constituent less than 5.0 percent in total volume. --tr = trace constituent 1 ess than 1. 0 percent in total volume.
® Converse Consultants Geotechnical Engineering
and Applied Sciences
C-10
PETROGRAPHIC REPORT
SHEET_l_ OF_l_
Project Name: Haines-Skagway Hydroelectric Project Job No.: 81-5165-16
Date Sampled: Analysis By: S.M. Testa Date: March 1, 1982
Sample No.: Pet-DH 103 Source: Boring 103 at a deQth of 7.6 feet.
Location: Left Abutment
Megascopic Classification: GRANODIORITE
PETROGRAPHIC ANALYSIS:
ROCK NAME: GRANODI OR ITE
MINERAL CONSTITUENTS:
Feldspar Opaque Mi nera 1 s m
Plagioclase 40 Apatite tr
Potash Feldspar 15 Chlorite tr
Quartz 20 Sericite tr
Biot ite 15
Hornblende m
DESCRIPTION:
Massive, fresh, coarse grained rock characterized by holocrystalline, hypidio-
morphic-granular texture. Feldspar and quartz are roughly of equal dimension.
Plagioclase occurs as euhedra 1 to subhedral crystals. Lath-like plagioclase
typically exhibits combined Albite-Carlsbad twinning and has an anorthite content
of about An40, that falling within the compositional range of andesine. Potash
fel dspar is predominately orthocl ase, completely anhedral and i nterst it i a 1 to
plagioclase. Quartz is anhedral, commonly exhibits strained wandering extinction
and also occurs as a myrmekit;c intergrowth; that being characterized by finger-
like bodies of quartz enclosed in plagioclase. Sericitization of the feldspars
is nominal. Bi ot ite forms independent fl akes with ragged edges. Both bi ot ite
and hornblende commonly show partial alteration to chlorite.
note: m = minor constituent less than 5.0 percent in total volume. --tr = trace constituent less than 1.0 percent in total volume.
@ Converse Consultants Geolechnical Engineering
and Applied Sciences
C-11
PETROGRAPHIC REPORT
SHEET_l_0F_l
Project Name: Haines-Skagway Hydroelectric Project Job No.: 81-5165-16
Date Sampled: Analysis By: S.M. Testa Date: March 12 1982
Sample No.: Pet-DH 104-1 Source: Boring 104 at a de~th of 35.6 feet.
Location: Left Abutment
Megascopic Classification: ALTERED DIORITE
PETROGRAPHIC ANALYSIS:
ROCK NAME: ALTERED DIORITE
MINERAL CONSTITUENTS:
Feldspar Opaque Mi nera 1 s tr
Plagioclase 45 Apatite tr
Quartz 20 Sericite 20
Biotite tr Ca 1 cite 10
Hornblende tr Chlorite tr
DESCRIPTION:
Massive, moderately altered, coarse grained rock characterized by holocrystal-
1 i ne, hypidiomorphic-granular texture. Plagioclase and quartz are roughly of
equal dimension. Plagioclase occurs as euhedral to subhedral crystals. Due to
considerable alteration of plagioclase to sericite, anorthite content was inde-
terminable. Quartz commonly exhibits strained wandering extinction. Both bi 0-
tite and hornblende are partially altered to chlorite. A thin irregular calcite-
filled fracture 2.0 mm in width transects the section.
note: m = minor constituent less than 5.0 percent in total volume. --tr = trace constituent less than 1.0 percent in total volume.
@ Converse Consultants Geotechnical Engineering
and Applied SCiences
C-12
PETROGRAPHIC REPORT
SHEET_l OF_l
Project Name: Haines-Skagway Hldroelectric Project Job No.: 81-5165-16
Date Sampled: Analysis By: S.M. Testa Date: March 1~ 1982
Sample No.: Pet-DH 104-2 Source: Bori ng 104 at a deQth of 140.5 feet.
Location: Left Abutment
Megascopic Classification: ALTERED DIORITE
PETROGRAPHIC ANALYSIS:
ROCK NAME: ALTERED DIORITE
MINERAL CONSTITUENTS:
Feldspar Bi ot ite tr
Plagioclase 45 Sericite 20
Quartz 20 Calcite 10
Opaque Minerals tr Chlori te m
Zi rcon tr
Apatite tr
DESCRIPTION:
Massive, moderately altered, coarse grained rock characteri zed by holocrystal-
1 i ne, hypi diomorphic-granul ar texture. Plagioclase and quartz are roughly of
equal dimension. Plagioclase occurs as euhedral to subhedral crystals. Due to
considerable alteration of plagioclase to sericite, aMrthite content was inde-terminable. Quartz is anhedral and exhibits strained wandering extinction.
note: m = minor constituent less than 5.0 percent in total volume. --tr = trace constituent 1 ess than 1.0 percent in total volume.
@ Converse Consultants Geotechnical Engineering
and Applied Sciences
C-13
PETROGRAPHIC 'REPORT
SHEET_l_ OF_l_
Project Name: Haines-Skagway Hydroelectric Project Job No.: 81-5165-16
Date Sampled: Analysis By: S.M. Testa Date: March 1, 1982
Sample No.: Pet-DH 107 Source: Bor; ng 107 at a deEth of 49.1 feet.
Location: Ri ght Abutment
Megascopic Classification: ALTERED GRANODIORITE
PETROGRAPHIC ANALYSIS:
ROCK NAME: ALTERED GRANODIORITE
MINERAL CONSTITUENTS:
Feldspar Opaque Mi nera 1 s tr
PlagioclasE~ 45 Chlorite m
Potash Feldspar 15 Sericite tr
Quartz 25
Biot ite 7
Hornblende m
Apatite tr
DESCRI PTION:
Massive, slightly altered, coarse grained rock characterized by holocrystalline,
hypidiomorphic-granular texture. Feldspar and quartz are roughly of equal dimen-
sion. Feldspar occurs as euhedral to subhedral crystals. Lath-like plagioclase
typically exhibits combined Albite-Carlsbad twinning and has an anorthite content
of about An40, that falling within the compositional range of andesine. Potash
feldspar is predominately orthoclase, completely anhedral and interstitial to
plagioclase. Quartz commonly exhibits undulose extinction. Sericiti zat ion of
the fel dspars is nominal. Biotite forms independent fl akes with ragged edges.
Both biotite and hornblende show partial alteration to chlorite.
note: m = minor constituent 1 ess than 5.0 percent in total vol ume.
tr = trace constituent less than 1.0 percent in total volume.
® Converse Consultants Geotechnical Engineering
and Applied Sciences
C-14
PETROGRAPHIC REPORT
SHEET_1_ OF_1_
Project Name: Haines-Skagway Hydroelectric Project Job No.: 81-5165-16
Date Sampled: Analysis By: S.M. Testa Date: March 1, 1982
Sample No.: Pet-OH 108 Source: Bori n9 108 at a de~th of 373.1 feet.
Location: Surge Tank
Megascopic Classification: ALTERED GRANODIORITE
PETROGRAPHIC ANALYSIS:
ROCK NAME: ALTERED GRANODIORITE
MINERAL CONSTITUENTS:
Feldspar Opaque Minerals m
Plagioclase 50 Sericite m
Potash Feldspar 15 Chlorite tr
Quartz 20
Bi otite 7
Hornb 1 ende tr
DESCRIPTION:
Massive, slightly altered, coarse grained rock characterized by holocrystalline,
hypidiomorphic-granular texture. Feldspar and quartz are roughly of equal dimen-
sion. Feldspar occurs as euhedral to subhedral crystals. Lath-like plagioclase
typically exhibits combined Albite-Carlsbad twinning and has an anorthite content
of about An42, that falling within the compositional range of andesine. Potash
feldspar is predominately ort hoc 1 ase, completely anhedral and i nterst it i a 1 to
plagioclase. Quartz commonly exhibits strained wandering extinction. Sericitiza-
tion of the feldspars is nominal. Biotite shows partial alteration to chlorite.
note: m = minor constituent 1 ess than 5.0 percent in total volume. --tr = trace constituent 1 ess than 1.0 percent in total volume.
@ Converse Consultants Geotechnical Engineering
and Applied Sciences
C-15
APPENDIX D
CONSTRUCTION MATERIALS TESTING
0.1 GENERAL
A limited laboratory testing program was completed on samples of poten-
tial construction materials (fine and coarse concrete aggregate and
gravel embankment fill).
A potential concrete aggregate and embankment borrow site was identified
within the reservoir site near the vicinity of the proposed dam site on
West Creek. An elevated alluvium terrace was explored by the excavation
of seven test pits and the observation of four existing cut banks, as
shown on Drawing 8.
Test pits were logged by our field representative; logs of these test
pits are included in Appendix B. Eighteen bulk samples were obtained
of representative materials that were considered to have potential use
in construction. Approximately 1,500 pounds of these materials were
shipped to the Seattle office laboratory of Converse Consultants.
Laboratory testing on aggregate and embankment materi a 1 s i ncl uded 16
grain size analyses, which were the basis for selecting representative
samples to be subjected to other aggregate quality tests. Grain size
distribution curves are shown on Drawings No. 0-7 through 0-46.
Tabulated below are the type of aggregate quality tests and the numbers
of each performed. All tests were performed in accordance with ASTM
standard test designations.
Converse Consultants, Inc.
.Itpe of Test
Specific Gravity
Absorpti on
Sodium Sulfate Soundness
L.A. Abrasion
Bu 1 k Dry Dens ity
Maximum Dry Density
Potential Rectivity
Petrologic Examination
0-2
ASTM Test
Designation
C127/128
C127/128
C88
C131
C29
02049
C289
C295
Number of
Tests Performed
5
5
5
6
5
5
5
5
Aggregate qua'lity test results are summar:ized on Table 0-1 and individ-
ual reports by Northwest Laboratories are included as pages 0-9 through
0-18. A descr'iption of the petrologic examinations and results are
presented in Section 0.2 of this appendix.
Five consolidated, drained triaxial compression tests were completed on
selected samp'les to determine preliminary strength properties for poten-
tial embankment soils. The results of these tests are shown on Drawings
0-1 through 0-5. The bulk samples as returned from the field were too
coarse for our triaxial test apparatus. Therefore, in accordance with
the methods suggested by Marachi, et a1. (1971) and Lowe (1964), test
specimens were fabricated such that the maximum particle diameter was
one-sixth of the sample diameter (maximum particle size about 0.4
inches) and the gradation
that of the bulk sample.
ings 0-47 through 0-51.
cent of the max i mum dry
tents of 8 to 9 percent.
curve for the test specimen was parallel to
These gradation curves are enclosed as Draw-
All test specimens were remo1 ded to 95 per-
de ns i ty as def i ned by ASTM 2049 at wate r con-
0.2 PETROLOGIC EXAMINATION OF FINE AGGREGATE
Five samples of fine aggregate proposed for use in Portland-cement con-
crete were examined by stereoscopic methods. The samples are identified
as test pits TP-I (SA-2), TP-2 (SA-2), TP-3 (SA-~), and TP-5 (SA-I), and
cut bank CB-2 (SA-I).
Converse Consultants, Inc.
D-3
The five samples were examined in accordance with ASTM C 295, Standard
Recommended Practice for Petrographic Examination of Aggregate for Con-
crete. Seven si ze fract ions of the sand were separated by si evi ng and
each fraction examined and analyzed in accordance with ASTM C 295. The
natural sand was separated into size fractions as follows: Retained on
U.S. Sieve No. 200, No. 100, No. 50, No. 30, No. 16, No.8 and No.4. No
quantitative analyses of the fraction passing the No. 200 sieve was at-
tempted.
The various constituents were classified with regard to their suita-
bility as fine aggregate ingredients for Portland cement. Physical
condition is defined as either satisfactory, fair or poor; chemical
stability in concrete is designated by either innocuous or deleterious.
Satisfactory particles are classified as hard to firm and relatively
free from fractures, capillary absorption is very small or absent, and
the surface texture is relatively rough. Particles classified as fair
exhibit one or two of the following qualities: firm to friable,
moderately fractured, capillary absorption small to moderate, surface
relatively smooth and impermeable and very low compressibility.
Particles classified as poor exhibit one or more of the following
qualities: friable to pulverulent, slake when wetted or dried, highly
fractured, deeply weathered, capillary absorption high and marked volume
change with wetting and drying. Innocuous part icles are those which
will not dissolve or react chemically to a significant extent with
constituents of the hydrating Portland cement, atmosphere or water under
ordinary conditions. Particles which are known to either react
chemically under conditions ordinarily prevailing in Portland-cement
concrete or mortar in such a matter as to produce s i gnifi cant vol ume
change, interfere with the normal course of hydration of Portland
cement, or supply substances that mi ght produce harmful effects upon
mortar or concrete are classified as deleterious.
D.2.1 Description
Test Pit TP-1, Sample SA-2
The sample consisted of 6.0 kg. of fine, dry sand. The sand is rather
simple in lithologic composition consisting predominately of subrounded
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0-4
to round, fine to medium-grained granitic rocks and sub-angular to an-
gular quartz, with minor schist, andesite, amphibole, mica, feldspar,
epidote and opaque minerals. Percentage of individual constituents in
each size fraction have been tabulated and are presented on Table 1.
Only minor proportions of the sample are retained on the U.S. No.4
sieve, consisting primarily of subrounded to round, fine to medium-
grained granitic rocks with minor basalt, notably andesite. The sand
retained in the No.8 to 200 fractions consist primarily of granitic
rocks and quartz with minor amphibole. Particles of granitic rocks
progressively decrease in abundance with a decrease in grain size, being
absent in fract ions smaller than the No. 16 sieve. On the other hand,
quartz makes up only 11.0 percent of the No.8 fraction, but remains es-
sentially constant in amounts between 73.0 to 88.3 percent in the No. 16
to 200 fractions. These particles are innocuous and free from coatings
of precipitated mineral matter, silt or clay.
Particles that are moderately weathered, porous or internally fractured
are classified as only fair in physical quality or constituents of ag-
gregate for concrete. Such particles constitute 2.0 to 9.7 percent of
seven fractions, averaging 5.8 percent. Particles that are deeply
weathered or soft, such as the micas, are classified as poor in phys-
ical quality as constituents of aggregate for concrete. Particles so
classified constitute nil to 3.9 percent of the various fractions exam-
ined, or an average of 1.8 percent. Such particles are present in the
No. 16 to 200 fractions, being most abundant (3.9 percent) in the No.
200 fraction.
The sample includes a small proportion of andesite. Intermediate to
acidic volcanic rocks, such as andesite, are similar in composition to
rock types known elsewhere to be potentially subject to a deleterious
degree of the alkali-silica reaction if used in concrete in combination
with Portland cement of high alkali content. However, such particles
constitute nil to 13.3 percent of the seven size fractions examined, or
an average of 2.2 percent, and are present in significant proportions in
only the fraction retained on the No.4 sieve, which is negligible in
amount.
Converse Consultants. Inc.
Const i tuents
Granite
Weathered Granite
Andesite
Schi st
Quartz
Weathered Quartz
Deeply Weathered Quartz
Amphibole
t~ica
Feldspar
Epidote
Opaque Minerals
TABLE 1
PETROGRAPHIC ANALYSIS OF FINE AGGREGATE
TEST PIT TP-1, SAMPLE SA-2
Amount as Number of Particles (percent)l Retained on
No. 42 No. 8 No. 16 No. 30 No. 50
80.0 85.3 13.7
6.7 0.7 1.0
13.3 1.7 0.3 0.3
0.3
11.0 73.0 77 .4 83.4
1.3 6.7 9.0 2.7
0.7 0.7
4.3 11.0 12.7
0.3 1.0 0.6
0.3
0.3 0.3
Sieve Fractions Shown Below
No. 100 No. 200
88.3 80.0
4.0 5.0
0.8 1.6
5.3 9.7
1.3 2.3
0.7
0.3 0.7
1Based on examination and identification of a minimum of 300 particles in each of the size fractions shown unless
otherw; se noted.
2Based on examination and identification of 15 particles.
The various constituents are classified as follows with regard to their suitability as ingredients of fine aggre-
gate for Portland-cement concrete:
Satisfactory: granite, andesite, schist, quartz, amphibole, feldspar, epidote, and opaques.
Fair: weathered types.
Poor: deeply weathered quartz and micas.
0-5
Test Pit TP-2, Sample SA-2
The sample consisted of 8.6 kg of fine, dry sand. The sand is generally
lithologically similar to sample TP-l (SA-2) consisting of subrounded to
round, fine to medium-grained granitic rocks predominating in the No.4
and 8 fractions, and subangular to angular quartz predominating in the
No. 16 to 200 fractions. Minor constituents include schist, andesite,
amphibole, mica, feldspar, epidote and opaque minerals. Percentages of
individual constituents in each size fraction have been tabulated and
are presented on Table 2.
Granitic rocks in the No.4 and 8 fractions constitute 95.7 and 87.0
percent of the fractions, respectively. Minor andesite and quartz
average 4.0 and 2.0 percent, respectively, in the two size fractions.
Quartz is relatively constant in abundance in the No. 16 through 200
fraction ranging from 82.7 to 89.3 percent, averaging 86.7 percent in
the five fractions examined. These particles are innocuous and free
from coatings of precipitated mineral matter, silt or clay.
Particles classified as only fair in physical quality constitute 2.3 to
4.4 percent of the seven size fractions examined, averaging 3.1 percent.
Particles that are deeply weathered or soft are classified as poor in
quality and constitute nil to 2.4 percent of the seven fractions exam-
ined, or an average of 0.8 percent.
Andesite, similar to rock types elsewhere known to be potentially sub-
j ect to a 1 ka 1 i -5 i 1 i ca react i on in concrete if combi ned wi th a hi gh-
alkali Portland cement constitute 0.3 to 6.0 percent in the No.4 to 30
fractions, averaging 2.2 percent. The No.8 fraction contains the high-
est abundance of andesite, constituting 6.0 percent of the fraction.
Test Pit TP-3, Sample SA-1
The sample consisted of 8.3 kg of fine, dry sand. Lithogically similar
to TP-1 (SA-2) and TP-2 (SA-2), the sand consists predominantly of sub-
rounded to round, fine to medium-grained granitic rocks and subangular
to angular quartz, with minor andesite, amphibole, mica, feldspar and
opaque minerals. Percentages of individual constituents in each size
fraction have been tabulated and are presented on Table 3.
Converse Consultants, Inc.
TABLE 2
PETROGRAPHIC ANALYSIS OF FINE AGGREGATE
TEST PIT TP-2, SAMPLE SA-2
Amount as Number of Particles (percent)l Retained on Sieve Fractions Shown Below
Const i tuents No. 4 No. 8 No. 16 No. 30 No. 50 No. 100 No. 200
Granite 94.7 87.0 0.3 3.7 1.0
Weathered Granite 3.0 3.0 0.3
Andesite 2.0 6.0 0.3 0.3
Schist 0.3
Quartz 4.0 89.0 86.7 85.6 89.3 82.6
Weathered Quartz 4.0 2.3 2.7 2.3 4.3
Deeply Weathered Quartz 0.7 0.3 0.7
Amphibole 5.4 6.7 7.7 5.7 10.0
Mica 0.7 1.7 1.7
Feldspar 0.3 1.7 0.7 0.7
Epidote 0.3
Opaque Minerals 0.3
IBased on examination and identification of a minimum of 300 particles in each of the size fractions shown.
The various constituents are classified as follows with regard to their suitability as ingredients of fine aggre-
gate for Portland-cement concrete:
Satisfactory: granite, andesite, schist, quartz, amphibole, feldspar, epidote, and opaques.
Fair: weathered types.
Poor: deeply weathered quartz and micas.
Constituents
Granite
Weathered Granite
Andesite
Quartz
Weathered Quartz
Deeply Weathered Quartz
Amphibole
Mica
Feldspar
Opaque Mi nera 1 s
TABLE 3
PETROGRAPHIC ANALYSIS OF FINE AGGREGATE
TEST PIT TP-3, SAMPLE SA-1
Amount as Number of Particles (percent)l Retained on
No. 4 No.8 No. 16 No. 30 No. 50
95.7 89.3 0.7
2.3 2.7
2.0 4.3 0.3
3.7 85.7 85.3 89.8
2.7 3.7 3.3
0.3 0.3
11.0 8.0 4.0
0.3 0.7 2.0
0.3 0.3
1.0 0.3
Sieve Fractions Shown Below
No. 100 No. 200
83.4 85.0
3.3 3.7
0.7
8.0 7.3
4.0 3.0
0.3 0.7
0.3 0.3
1Based on examination and identification of a minimum of 300 particles in each of the size fractions shown.
The various constituents are classified as follows with regard to their suitability as ingredients of fine aggre-
gate for Portland-cement concrete:
Satisfactory: granite, andesite, quartz, amphibole, feldspar, and opaques.
Fair: weathered types.
Poor: deeply weathered quartz and micas.
D-6
Rounded to subrounded granitic rocks predomi nate in the No. 4 and 8
fractions in amounts of 95.7 and 89.3 percent, respectively, and ande-
site occurs in amounts of 2.0 and 4.3 percent, respectively. The sand
retained in the No. 16 to No. 200 fractions consisted predominantly of
quartz which is relatively constant in abundance ranging from 83.4 to
89.8 percent, averaging 85.8 percent. These particles are innocuous and
free from coatings of precipitated mineral matter, silt or clay.
Particles classified as only fair in physical quality constitute 2.3 to
3.7 percent of the seven fractions examined, averaging 3.1 percent.
Particles classified as poor in quality constitute 0.3 to 4.7 percent,
averaging 2.3 percent, in the No. 16 to 200 fraction, and are absent in
the No.4 and 8 fractions. The greater abundance of these constituents
are in the No. 100 and 200 fractions, 4.7 and 3.0 percent, respective-
ly.
Andesite, similar to rock types elsewhere known to be potentially sub-
ject to a 1 ka 1 i -s i 1 i ca reaction in concrete if combi ned with a hi gh-
alkali Portland cement, constitute 0.3 to 4.3 percent in the No.4 to 16
fraction, averaging 2.2 percent. The No.8 fraction contains the high-
est abundance of andesite, constituting 4.3 percent of the fraction.
Test Pit TP-5, Sample SA-1
The sample consisted of 7.2 kg of fine, dry sand, lithologically similar
to the previously described samples. The sand consisted predominantly
of subrounded to round, fine to medium-grained granitic rocks and sub-
angular to angular quartz, with minor andesite, amphibole, mica and
opaque minerals. Percentage of individual constituents in each size
fraction examined have been tabulated and are presented on Table 4.
Rounded to subrounded granitic rocks predomi nate in the No. 4 and 8
fractions in amounts of 93.0 and 85.3 percent, respectively, with nil in
the No. 16 to 200 fract ions. Sand retai ned in the No. 16 to 200 frac-
tions consisted predominantly of subangular to angular quartz which is
relatively constant in abundance ranging from 84.7 to 89.1 percent,
averaging 87.2 percent. These particles are innocuous and free from
coatings of precipitated mineral matter, silt or clay.
Converse Consultants, Inc.
Constituents
Grani te
Weathered Granite
Andesite
Quartz
Weathered Quartz
Oeeply Weathered Quartz
Amphibole
Mica
Opaque Minerals
TABLE 4
PETROGRAPHIC ANALYSIS OF FINE AGGREGATE
TEST PIT TP-5, SAMPLE SA-1
Amount as Number of Particles (percent)l Retained on
No. 4 No. 8 No. 16 No. 30 No. 50
93.0 85.3
5.7 3.7
1.3 8.0
3.0 85.3 84.7 89.1
5.7 5.3 3.3
1.0
7.3 7.0 3.0
0.7 3.0 4.3
0.3
Sieve Fractions Shown Below
No. 100 No. 200
89.0 88.1
4.0 2.3
0.7
3.7 7.3
2.6 2.3
1Based on examination and identification of a minimum of 300 particles in each of the size fractions shown.
The various constituents are classified as follows with regard to their suitability as ingredients of fine aggre-
gate for Portland-cement concrete:
Satisfactory: granite, andesite, quartz, amphibole, and opaques.
Fair: weathered types.
Poor: deeply weathered quartz and micas.
0-7
Particles classified as only fair in physical quality constitute 2.3 to
5.7 percent of the seven fractions examined, averaging 4.2 percent.
Particles classified as poor in quality constitute 1.7 to 4.3 percent of
the No. 16 to 200 fractions, averaging 2.9 percent. The greater abun-
dance of these constituents are in the No. 50 fractions, being comprised
predominantly of mica.
Andesite, similar to rock types elsewhere known to be potentially sub-
ject to alkali-silica reaction in concrete if combined with high-alkali
Portland cement, constitute 1.3 and 8.0 percent of the No.4 and 8 frac-
tions, respectively.
Cut Bank CB-2, Sample SA-1
The sample consisted of 8.0 kg of fine, dry sand. Lithogically similar
to the previously described samples, the sand consisted predominantly
of subrounded to round, fine to medium-grained granitic rocks and sub-
angular to angular quartz, with minor andesite, amphibole, mica and
opaque minerals. Percentages of individual constituents in each size
fraction examined have been tabulated and are presented on Table 5.
Rounded to subrounded granit ic rocks predomi nate in the No. 4 and 8
fractions in amounts of 92.7 and 88.0 percent, respectively, with nil in
the No. 16 to 200 fractions. Sand retained in the No. 16 to 200 frac-
tions consisted predominantly of sub-angular to angular quartz which is
relatively constant in abundance ranging from 83.0 to 89.1 percent,
averagi ng 87.1 percent. These part ic les are innocuous and free from
coatings of precipitated mineral matter, silt or clay.
Particles classified as only fa-ir in physical quality constitute 1.7
to 4.6 percent of the seven fract ions exami ned, averagi ng 6.1 percent.
Particles classified as poor in quality constitute 0.3 to 5.3 percent of
the No. 16 to 200 fract ions, averag; ng 3.7 percent. The greater abun-
dance of these const ituents are in the No. 30 to 200 fract ions bei ng
comprised predom-inately of mica.
Andesite, similar to rock types elsewhere known to be potentially sub-
ject to alkali-silica reaction in concrete if combined with high-alkali
Portland cement, constitute 1.7, 3.0 and 0.7 percent of the No.4, 8 and
16 fractions, respectively.
Converse Consultants, Inc_
Constituents
Granite
Weathered Grani te
Andesite
Quartz
Weathered Quartz
Deeply Weathered Quartz
Amphibole
t1ica
Opaque Minerals
TABLE 5
PETROGRAPHIC ANALYSIS OF FINE AGGREGATE
CUT BANK CB-2, SAMPLE SA-1
Amount as Number of Particles (percent)l Retained on
No. 4 No. 8 No. 16 No. 30 No. 50
92.7 88.0
4.3 1.7
1.7 3.0 0.7
1.0 7.3 88.0 83.0 88.7
0.3 4.3 4.0 3.0
0.7
6.7 8.7 3.7
0.3 3.6 4.3
0.3
Sieve Fractions Shown Below
No. 100 No. 200
89.1 86.7
2.3 2.7
0.3
4.3 5 .. 0
4.0 5.3
0.3
lSased on examination and identification of a minimum of 300 particles in each of the size fractions shown.
The various constituents are classified as follows with regard to their suitability as ingredients of fine aggre-
gate for Portland-cement concrete:
Satisfactory: granite, andesite, quartz, amphibole, and opaques.
Fair: weathered types.
Poor: deeply weathered quartz and micas.
0-8
D.2.2 Conclusions
The five natural sand samples examined are satisfactory for use as fine
aggregate in Portland-cement concrete for permanent construction. All
five samples are similar in lithologic composition consisting primarily
of granitic rocks and quartz, with minor andesite, amphibole, mica and
opaque minerals, and trace amounts of schist, feldspar and epidote.
Rounded to subrounded granit i crocks predomi nate in the No. 4 and 8
fract ions rangi ng from 80.0 to 95.7 percent, averagi ng 89.1 percent in
the five samples examined. Angular to subangular quartz predominates in
the No. 16 to 200 fractions ranging from 73.0 to 89.8 percent, averag-
ing 85.8 percent in the five samples examined. These constituents are
innocuous and free from coatings of precipitated mineral matter, silt or
clay.
Particles classified as fair for fine aggregate in Portland-cement
concrete consist of weathered types which in the five samples examined
range in abundance from 3.1 to 5.8 percent, averaging 3.9 percent.
Particles classified as poor range from 0.8 to 2.6 percent, averaging
1.7 percent, in the five samples examined.
The samples included small amounts of andesite which is classified as
deleterious and potentially subject to the alkali-silica reaction in
concrete. Alkali-silica reactivity occurs as concrete is setting and
hardening. Hydration of the cement takes place and alkalies are releas-
ed which in turn react with all silicates and silica-minerals. In the
five samples examined, andesite constitutes from 1.3 to 13.3 percent,
averaging 4.4 percent in the No.4 and 8 fractions. The greater prepon-
derance of andesite occurs in the No.4 fraction in sample TP-l (SA-2),
and in the No.8 fraction of sample TP-5 (SA-I) at 13.3 and 8.0 percent,
respectively. It should be noted that significant proportions of ande-
site occur in only the fraction retained on the No. 4 sieve in sample ,
TP-I (SA-2), which is negligible in amount. Considering all seven frac-
tions examined, andesite constitutes only 0.8 to 2.2 percent, averaging
1. 3 percent.
Converse Consultants, Inc.
0-9
NORTHWEST LABORATORIES
of Seattle, Incorporated
Technical Services for: Industry, Commerce, Legal Profession & Insurance Industry
1530 FIRST AVENUE SOUTH • SEATTLE, WASHINGTON 98134 • Telephone: (206) 622-0680
Report to: Converse Consultants Date: March 2, 1982
Report on: Aggregate Lab. No. E 24424-1
I DENT! FI CAT! ON :
Pit Run Aggregate samples submitted
Haines-Skagway Hydro (#81-5165-16)
Sample TP-1, S-2 (52.4 1bs.)
LOS ANGELES ABRASION TEST -ASTM C131
Coarse Aggregate;
Grading Insufficient Sample
to conduct tests.
Wear After 500 Revolutions, %
SOUNDNESS TEST -ASTM C88
Coarse Aggregate:
Original Weight of Test % Passing Finer
Grading Fracti on Before Sieve After Test
Pass i ng Retai ned % Test, gms Actual % Loss
pll '2 3/4 11 47 1 ,520 0.66
3/4 11 3/8 11 33 1 ,010 0.84
3/8 11 #4 17 300 1. 00
#4 3 1. 00
Totals 100 2,830
Major loss due to crumbling and flaking -no splitting occurred
Fine Aggregate:
#100 3.7
#50 #100 8.5
#30 #50 18. 1 100 5.0
#16 #30 18.4 100 2.0
#8 #16 22.3 100 9.0
#4 #8 24.7 100 4.0
3/8 11 #4 4.3 4.0
Totals 100. a 400
Weighted Aggregate
Corrected Percent
Loss
0.31
0.28
0.17
0.03
0.79
0.91
0.36
2.01
0.99
0.17
4.44
0-10
NORTHWEST LABORATORIES
of Seattle, Incorporated
Converse Consultants
E 24424-1
Page 2
POTENTIAL REACTIVITY OF AGGREGATE: ASTM C289
Sample
Reduction of Alkalinity, Rc*
Dissolved Silica, Sc*
*Mi 11 i 11101 es per 1 iter
Coarse
108
11
Fi ne
115
10
Reference Figure 2 ASTM C 289, the Aggregates fall well within the
area considered innocuous.
NORTHWEST LABORATORIES
lb
D-11
NORTHWEST L.ABORATORIES
of Seattle, incorporated
Technical Services for: Industrv, Commerce, Legal Profession & Insurance Industrv
1530 FIRST AVENUE SOUTH • SEATTLE, WASHINGTON 98134 • Telephone: (206) 622-0680
Report to: Converse Consultants
Report on: Aggregate
!DENT! FICATION:
Pit Run Aggregate samples submitted
Haines-Skagway Hydro (#81-5165-16)
Sample TP-2, S-2 (8l.5 lbs.)
LOS ANGELES ABRASION TEST -ASTM C131
Coarse Aggregate;
Grading
Wear After 500 Revolutions, %
SOUNDNESS TEST -ASTM C88
Coarse Aggregate:
A
51. 7
Original Weight of Test
Gradi ng Fraction Before
Passing Retained 01 to Tes t, gms
1~" 3/4" 47 1 ,514
3/4 11 3/8" 33 1 ,000
3/8" #4 17 300
#4 3
Totals 100 2,814
t~ajor loss due to crumbling and flaking
Fi ne Aggregate:
#100 3.7
#50 #100 8.5
#30 #50 18. 1 100
#16 #30 18.4 100
#8 #16 22.3 100
#4 #8 24.7 100
3/8" #4 4.3
Totals 100.0 400
Nature of Solution -Saturated Sodium Sulfate
Date: March 2, 1982
Lab. No. E 24424-2
% Passing Finer Weighted Aggregate
Sieve After Test Corrected Percent
Actual % Loss ' Loss
0.93 0.44
0.80 0.26
0.67 0.11
0.67 0.02
0.83
3.0 0.54
4.0 0.74
4.0 0.89
2.0 0.49
2.0 0.09
2.75
CONFIDENTIAL REYORT PUBL.ICATIOf'.l RIG""ITS RESERVED PENDING WRITTEN AUTHORIZATION
D-12
NORT'HWEST LABORATORIES
of Seattle, Incorporated
Converse Consultants
E 24424-2
Page 2
POTENTIAL REACTIVITY OF AGGREGATE: ASTM C289
Sample
Reduction of Alkalinity, Rc*
Dissolved Silica, Sc*
*Millimoles per liter
Coarse
138
11
Fine
155
9
Reference Figure 2 ASTM C 289, the Aggregates fall well within the
area considered innocuous.
NORTHWEST LABORATORIES
~~
ALBERT O. WAH TO
lb
0-13
NORTHWEST LABORATORIES
of Seattle, incorporated
Technical Services for: Industry, Commerce, Legal Profession & Insurance Industrv
1530 FIRST AVENUE SOUTH • SEATTLE, WASHINGTON 98134 • Telephone: (206) 622·0680
Report to: Converse Consultants
Report on: Aggregate
I DENTI FI CATION:
Pit Run Aggregate samples submitted
Haines-Skagway Hydro (#81-5165-16)
Sample TP-3, S-l (87.25 1 bs.)
LOS ANGELES ABRASION TEST -ASTM C131
Coarse Aggregate;
Gradi ng A
Wear After 500 Revolutions, % 45.5
SOUNDNESS TEST -ASTM C88
Coarse Aggregate:
Original Weight of Test
Gradi ng Fraction Before
Pass i ng Retained Test, gms
pn '2 3/4" 47 1 ,520
3/4 11 3/811 33 1 ,010
3/811 #4 17 300
#4 3
Totals 100 2,830
l'I1ajor loss due to crumbling and flaking
Fine Aggregate:
#100 3.7
#50 #100 8.5
#30 #50 18. 1 100
#16 #30 18.4 100
#8 #16 22.3 100
#4 #8 24.7 100
3/811 #4 4.3
Totals 100.0 400
Nature of Solution -Saturated Sodium Sulfate
CONFIDENTIAL REPORT " PUBLICATION R:GJ--q 5
Date:
Lab. No.
March 2, 1982
E 24424-3
% Passing Finer
Sieve After Test
Actual % Loss
1. 32
0.99
0.67
0.67
5.0
4.0
6.0
4.0
4.0
Weighted Aggregate
Corrected Percent
Loss
0.62
0.33
0.11
0.02
1.08
0.91
0.74
1.34
0.99
0.17
4.15
D-14
NOR1'HWEST LABORATORIES
of Seattle. Incorporated
Converse Consultants
E 24424-3
Page 2
POTENTIAL REACTIVITY OF AGGREGATE: ASTM C289
Sample
Reduction of Alkalinity, Rc*
Dissolved Silica, Sc*
*Millimoles per liter
Coarse
83
9
Fine
118
9
Reference Figure 2 ASTM C 289, the Aggregates fall well within the
area considered innocuous.
NORTHWEST LABORATORIES
ALBERT O. WAHTO
lb
COHflOIlN'fUd .. R~~"T • rUBUCATIOH '''CMT. lIIti':st:"YI:O ,.eHOJNG WlilllTTI[H AUTHORIZATION.
0-15
NORTHWEST LABORATORIES
of Seattle, Incorporated
Technical Services for: Industry, Commerce, Legal Profession & Insurance Industry
1530 FIRST AVENUE SOUTH • SEATTLE, WASHINGTON 98134 • Telephone: (206) 622-0680
Report to: Converse Consultants Date: March 2, 1982
Report on: Aggregate Lab. No. E 24424-4
I DENT! FI CAT! ON:
Pit Run Aggregate samples submitted
Haines-Skagway Hydro (#81-5165-16)
TP-5, S-l (46.8 1bs.)
LOS ANGELES ABRASION TEST -ASTM C131
Coarse Aggregate;
Grading Insufficient Sample
to Conduct Test
Wear After 500 Revolutions, %
SOUNDNESS TEST -ASTM C88
Coarse Aggregate:
Ori gina 1 Wei ght of Tes t % Pass i ng Fi ner
Grading Fraction Before Sieve After Test
Passing Retained % Tes t, gms Actual % Loss
pit -'2 3/4" 47 1 ,520 1. 15
3/4" 3/8" 33 1 ,015 0.99
3/8" #4 17 300 1.33
#4 3 1. 33
Totals 100 2,835
Major loss due to crumbling and flaking
Fine Aggregate:
#100 3.7
#50 #100 8.5
#30 #50 18. 1 100 8.0
#16 #30 18.4 100 5.0
#8 #16 22.3 100 5.5
#4 #8 24.7 100 5.0
3/8" #4 4.3 5.0
Total s 100.0 400
Nature of Solution -Saturated Sodium Sulfate
CONt:"IOENTIAL . PUBLICATION R!GHTS RESERVED PEN;::)!NG WRITTEN AUTHORIZATION
Weighted Aggregate
Corrected Percent
Loss
0.54
0.33
0.26
0.04
1.17
1.45
0.92
1. 23
1. 24
0.22
5.06
0-16
NORI'HWEST LABORATORIES
of Seattle. Incorporated
Converse Consultants
E 24424-4
Page 2
POTENTIAL REP.CTIVITY OF AGGREGATE: ASTM C289
Sample Coarse
Reduction of Alkalinity, Rc* 75 100
Dissolved Silica, Sc* 9 6
*Millimoles per liter
Reference Figure 2 ASTM C 289, the Aggregates fall well within the
area considered innocuous.
NORTHWEST LABORATORIES
lb
0-17
NORTHWEST LABORATORIES
of Seattle, Incorporated
Technical Services for: Industry, Commerce, Legal Profession & Insurance Industry
1530 FIRST AVENUE SOUTH • SEATTLE, WASHINGTON 98134 • Telephone: (206) 622-0680
Report to: Converse Consultants
Report on: Aggregate
I DENTI FI CATION:
Pit Run Aggregate samples submitted
Haines-Skagway Hydro (#81-5165-16)
CB-2, S-1 (70. 1 1 bs . )
LOS ANGELES ABRASION TEST -ASTM C131
Coarse Aggregate;
Grading
Wear After 500 Revolutions, %
SOUNDNESS TEST -ASTM C88
Coarse Aggregate:
A
48.4
Original Wei ght of Test
Grading Fraction Before
Pass-ing Retained % Tes t, gms
pll '2 3/4 11 47 1 ,538
3/4 11 3/8 11 33 1 ,015
3/811 #4 17 300
#4 4
Totals 100 2,853
Major loss due to crumbling and flaking
Fine Aggregate:
#100 3.7
#50 #100 8.5
#30 #50 18. 1 100
#16 #30 18.4 100
#8 #16 22.3 100
#4 #8 24.7 100
3/8 11 #4 4.3
Totals 100.0 400
Nature of Solution -Saturated Sodium Sulfate
Date: March 2, 1982
Lab. No. E 24424-5
% Pass i ng Fi ner Weighted Aggregate
Sieve After Test Corrected Percent
Actual % Loss Loss
1. 17 0.55
1. 48 0.48
2.00 0.34
2.00 0.06
1.43
10.0 1. 81
6.0 1. 10
8.0 1. 78
6.0 1.48
6.0 0.26
6.43
CONFIDENTIAL REPORT PUBLICATION RIGHTS RtSERVLO PtNOING WRITTEN AUTHORIZATION
0-18
NOR~rHWEST LABORATORIES
of Seattle. Incorporated
Converse Consultants
E 24424-5
Page 2
POTENTIAL REACTIVITY OF AGGREGATE: ASTM C289
Sample
Reduction of Alkalinity, Rc*
Dissolved Silica, Sc*
*Millimoles per liter
Coarse
90
9
Fine
140
9
Reference Figure 2 ASTM C 289, the Aggregates fall well within the
area considered innocuous.
NORTHWEST LABORATORIES
~~
ALBERT O. WAHTO
lb
ASTM DESIGNATION D 422 C 295
Sample Location Soil Type Gradation Petrograph i c
and Number (USCS) Analysis
Sample 1 SW X ~-4.5_' _ -_.-f---f----TP-l Sample 2
5.0-6.0' SW-SM X X
Sample 1 SM X 3.0-3.5'
TP-2 1----_.--------1------
Sample 2 GP X X 4.5-5.0'
TP-3 Sample 1 GW X X 3.0-3.5'
TP-4 Sample 1 GW X 3.0-3.5'
Sample 1 SW X X 2.5' 1---._--------I-----.-
TP-5 Sample 2 SM X 3.5'
1----.----I-----f-----
Sample 3 ML X 4.5'
Sample 1 SP X 27-35'
TP-6 ~-'.---1---1---
Sample 2 ML X 3.9-4.9'
Cut Sample 1 GW X Bank 2.0-3.0'
1
Cut Sample 1 Bank GW X X
2 5.0-6.0'
Cut Sample 1 Bank SW X
3 4.0-5.0'
Cut Sample 1 GW X Bank ~0-6.0~ -------4 ----
Sample 2 SP X 8.2-10.0'
Table 0-1
LABORATORY TEST SUMMARY
Potential Concrete Aggregate
C 127 C 128 C 88
Bulk Absoll'tion Specific Gravity Absorption Sodium Sui fete
Sped fi c Gravity (%) (Sat. Surface Dry) (%) Soundness
(Sat. Surface Dry) Coarse Grain Fine Grain Fine Grain (% I 55)
Coarse Grain coarse fme
---_.--.--f--------f-----'------
2.63 1.6 2.49 4.8 0.8 4.4
-------------1------I----
2.66 0.7 2.64 2.0 0.8 2.7
2.59 2.3 2.60 1.8 1.1 4.1
2.66 0.6 2.61 1.4 1.2 5.1
r------.-r-----1----------I------
1-------1------1------------I------
f-------1---f--------1----_.-1--I---
2.66 0.7 2.64 0.9 1.4 6.4
1-------t------1-------1-------I--
C 131 C 29 D 2049 C 289
L.A. Abrasion Dry Bulk Maximum Potential Reactivity Triaxial
500 Revs Density Dry (millimol es/1iter) Test
(% loss) (oc..f) Density dissolved reduction in
loose compact (pcf) Silica Alkalinitv
coarse finE coarse line
-----------------r---1----
105 110 127 11 10 108 115 X
1------I---_.-f-----1----1--1-----1-----
51.7 129 140 135 11 9 138 155 X
45.5 117 123 131 9 9 83 118 X
40.6
113 115 128 9 6 75 100 X -----I----1----------t--1----1----1----
1------1----_.-1--t--I----1-----
1-------I---I----t----1---1--f----1----
32.7
48.4 121 133 135 9 9 90 140 X
31.6
f-------I----1---'----;----1----
Converse Consultants
5 10 15
<_I I .. --·"t
• • r • •
50
ti:' 40 on
~
f/)
f/)
w a: 30 t-..,
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AXIAL STRAIN (II»)
-*
~ j:' INITIAL FINAL (1 )TEST VALUES AT FAILURE
INITIAL ;.iO -..J il. w u.. BACK 0 _z ..J ~ APPL VOLUME EFF EFF III xI-~ a. :x: DRY WAT DRY WAT DEV DESCRIPTION :::!: ::!U) f/) :::l: I-DENS CONT LAT /STRESS r-HANGE LAT VERT. PRESS
>-a::w W <r. a. DENS CONT
STRESS USED U) 1-1-U) W (%) (PCF) (%) PRESS flV PRESS ~ Cl (PCF) ( KSF) (KSF) (KSF) (2) (KSF) (KSF) :
• 1 1 2 5-6' 120.6 9 14.4 25.0 +0.1 5.8 30.8 8.6 SP
• 1 2 120.6 9 14.4 33.8 +0.4 8.6 42.4 5.8
A 1 2 120.6 9 14.4 43.9 +0.8 11.5 55.4 2.9
NOTES: (0 FAILURE DEFINED BY MAXIMUM DEVIATOR STRESS
(2) VOLUME INCREASE IS POSITIVE; VOLUME DECREASE IS NEGATIVE.
(3) Samples remolded to 95% of maximum dry density (ASTM D2049).
CONSOLIDATED DRAINED TRIAXIAL COMPRESSION TESTS
A1aska Power Authori t'y
WEST CREEK PROJECT
for R. W. Beck and Associates, Inc.
~ Converse Consultants
Project No.
81-5165
Drawing No.
D-1
5 10 15
50
G: 40
II)
~
VJ
VJ
W a: 30 I-~
b VJ I
a: ....
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l-i=' INITIAL FINAL (1 )TEST VALUES AT FAILURE INITIAL
...J ;:id a. W L.l.. BACK 0 _Z ...J ~ APPL VOLUME EFF EFF IX) x ..... l-n. J: DRY WAT DRY WAT DEV DESCRIPTION ::e ::fC/) VJ :::E ..... DENS CONT DENS CONT LAT ~TRESS ~HANGE LAT VERT. PRESS >-D::W W «. n.
STRESS: USED C/) .......... C/) W (pcn (%) (PCFj (%) PRESS ( KSF) I( flV PRESS I-0
(KSF) • (KSF) (KSF) 2) (KSF)
• 2 2 4.5-5 133.0 8 14.4 32.7 -0.7 5.8 38.5 8.6 GP
.. 2 2 2 133.0 8 14.4 43.1 -0.5 8.6 51.7 5.8
• 2 2 133.0 8 14.4 55.2 +0.1 11.5 66.7 2.9
NOTES: (1) FAILURE DEFINED BY MAXIMUM DEVIATOR STRESS
(2) VOLUME INCREASE IS POSITIVE; VOLUME DECREASE IS NEGATIVE.
(3) Samples remolded to 95% of maximum dry density (ASTM D2049),
CONSOLIDATED DRAINED TRIAXIAL COMPRESSION TESTS
A1 aska Power Authori ty
WEST CREEK PROJECT
fo~ R.W. Beck and Associates, Inc.
@ Converse Consultants
Project No.
Orawing No.
D-2
5 10 15
I: Y
50
t·· . :':
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u:: 40
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0
> -4.0
. . .
AXIAL STRAIN (CJ(,)
a: c
W
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30 40
NORMAL STRESS (KSF)
.... ;.:; INITIAL FINAL (OTEST VALUES AT FAILURE
....J •
....J <t 0 1:1. lLJ iJ.-0 _z ....J ~ APPL VOLUME aJ xI-.... 0. :::c DRY WAT DRY WAT DEV EFF EFF
::E ~U) CI) :E I-LAT ~TRESS ~HANGE LAT VERT ,... O::lLJ W <t. 0. DENS CONT DENS CONT
U) 1-1-U) lLJ (PCF) (%) (PCF) (%l PRESS ( KSF) t:,v PRESS STRESS .... 0
(KSF) (2) (KSF) (KSF)
• 3 3 , 3-3~ 125 8 14.4 27.7 -0.5 5.8 33.5
... 3 1 125 8 14.4 38.7 -0.3 8.6 47.3
• 3 1 125 8 .4 46.3 0.0 11.5 57.8
= NOTES: (1) FAILURE DEFINED BY MAXIMUM DEVIATOR STRESS
(2) VOLUME INCREASE IS POSITIVE; VOLUME DECREASE IS NEGATIVE.
(3) Samples remolded to 95% of maximum dry density (ASTM D2049)
INITIAL
! BACK
' PRESS
. USED
(KSF)
8.6
5.8
2.9
DESCRIPTION
GW
CONSOLIDATED DRAINED TRIAXIAL COMPRESSION TESTS
2
AI as:tn Power Authori ty
WEST CREEK PROJECT
for R.W. Beck and A.ssocir]tes. Inc .
@ Converse Consultants
Project No.
81-51(,5
Drawing No.
D-3
5 10 15
, ;
50
G:' 40
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I-INITIAL FINAL (OTEST VALUES AT FAILURE INITIAL ...J • -~ ...J <[0 0.. w to.. ! BACK 0 _z ...J -APPl VOLUME EFF EFF ttl xI-a. :r: DRY WAT DRY WAT DEV I-~ I PRESS ::e ~If) tI) I-DENS CONT DENS CONT lAT ~TRESS ~HANGE lAT VERT >-o::w W
<[. a. . USED If) 1-1-If) W (PCF) (%) (PCF) (%) PRESS ( KSF) t,V PRESS STRESS l-e (KSF) ; (KSF) (KSF) (2) (KSF)
... 4 5 1 2.5 121.6 9 14.4 26.5 -0.8 5.8 32.3 8.6
• 5 1 121.6 9 14.4 40.0 -0.7 8.6 48.6 5.8
• 5 1 121.6 9 14.4 46.6 -0.3 11.5 2.9
NOTES: (1) FAILURE DEFINED BY MAXIMUM DEVIATOR STRESS
(2) VOLUME INCREASE IS POSITIVEi VOLUME DECREASE IS NEGATIVE.
(3) Samples remolded to 95% of maximum dry density (ASTM D2049),
DESCRIPTION
SW
CONSOUDATED DRAINED TRIAXIAL COMPRESSION TESTS
Alaska Power Authority
WEST CREEK PROJECT
for R.W. Beck and Associates, Inc.
~ Converse Consultants
Project No.
81-5165
Drawing No.
0-4
&
50
40 tL
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(2)
(3)
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5-6
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INITIAL
DRY WAT
DENS CONT
(PCF) (%)
127.9 8
127.9 8
127. S 8
M
NORMAL
FINAL (1 )TEST VALUES AT FAILURE
DRY WAT APPL DEV VOLUME EFF EFF
DENS CONT LAT STRESS /CHANGE LAT VERT
(PCF) (%) PRESS ( KSF) 6V PRESS STRESS
(KSF) (2) (KSF) (KSF)
14.4 31.5 -0.6 5.8 37.3
14.4 42.9 0.1 8.t 51.5
14.4 47.0 0.3 1 1.5 58.5
FAILURE DEFINED BY MAXIMUM DEVIATOR STRESS
VOLUME INCREASE IS POSITIVE; VOLUME DECREASE IS NEGATIVE.
Sampl es remolded to 95% of maximum dry density (ASTM D2049)
crt
INITIAL
BACK
' PRESS DESCRIPTION
USED
(KSF)
8.6 GW
5.8
2.9
CONSOLIDATED DRAINED TRIAXIAL COMPRESSION TESTS
AI aska Power Authori ty
WEST CREEK PROJECT
for R. W. Beck and Associates, Inc.
@ Converse Consultants
ProJ',cl No,
81-51f,5
Drawing No,
0-5
-..c;
CI
'il :.
>.
~
~
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r:: --r::
Q)
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100
90
80
70
60
50
40
30
20
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r-
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7
7
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./
Specific Grovity,+#4_ • .!4_
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#
I
I
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/
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/
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Remarks: ______________________ _
I
/
SIEVE ANALYSIS
Screen Size
(D o:::t
# rt) rt)
I
I
7
7
7
7
/
/
/
7
/
/
1/
/
/
/
/ /
/'
./ /
/' /
II
7
/
/
/
/
/
7
Location Borrow Area
Pit No. Test Pit 1
Elev. or De pth'4
Ft., From 3. To 4.5
--IN : : -rt) CD e
//
//
//
/ /
/ / 10
/
/
I 20
I -30 ..c;
CI
'ii)
)I
40 >.
~
~
Q,) en
~
50 0
0
(,) -r::
60 Q)
(,)
~
Q,) a.
70
80
90
100
Pr~ectHaine-Skagway Hydroelectric
Work order ____ ---:=-=::--_~..,..".....,....."
Drown ~ Checked DER Date 3/5/82
Sample No. --:;.1 _____ --=--__ _
DRAWING NO. 0-6
50
40
10
o
FINE AGGREGATE GRADATION
Size or openin~ in inches
en C\I U") ...... rt) en ...... 0 ~ V S 0 0 0
0 0 0 0 0
~ V \
V l------
V
Pan No. 100 No. 50 No. 30
Screen size
No. IS No.8
1.0
!!!
0
No.4
Screen
size
No.4
NO.8
No. 16
No. 30
No. 50
No. 100
Pon
Fineness modulus
Percent sand clean separation): 30
(Scre.n sizes are based on square OPenin~s)
Project Haines kagway Hydroelectric
Work Order _________ _
Borrow Area Location
Pit No. Test Pit 1, Sampl e 1
Elev. or Depth ft., From ~ to 4.5
Drown BH Checked ~ Oate 3/8/82
DRAWING NO. D-7
"0
!
-0 .... • ...
.... c:: .,
u ... • Q..
50
40
30
20 ~
10
o
No.4
COARSE AGGREGATE GRADATION
----'
]. in.
S
/ \
], In.
4
Screen size
31n. 61n.
Screen % Retained
size Individual Cumulative
6 In. 0 0
3 In. 0 0
1112 in 20 20
3/4 in. 42 62
3/8 in. 21 83
No.4 17 100
Pan
Percent coarse aggregate = 70
(Screen sizes are baled on squart openings)
ProjectHajoes-Skagway Hydroelectric
Work Order ________ _
Location Borrow Area
Pit No. __ T..;;.,e..;..s t.:..-..-P_i _t .....:1:..:.,_Sa_m~p_l_e _1_
Elev. or Depth ft, From...3.....5-to _~
Drawn BH Checked ..QE.£L Date 3/5/82
DRAWING NO. D-8
-.s::.
CI . iii
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100
90
80
70
60
50
40
30
20 /'
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10
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#
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/ /
/ /
I /
/
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7
7
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7
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Specific Grallity,':4_, ~4_
(D
#
/
'/
/
/ /
/ /
I
/
/
/
/
Remarks: __________________ _
SIEVE ANALYSIS
Screen Size
Q) v
# ~t ,.., ,..,
/ -/ ~
/ ./
7 /' / [7 ....
./
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/ /'
/
/ /'
/ /' /
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Pit No. Test Pit 1
Elell. or DePlh~
Ft., From . To 6.0
--IN -
./
/
/
= : ,.., CD
0
10 ----
20
30 :c
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40 ~
.0 ....
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VI ....
50 c
0
(.) -c:
60 CI)
(.)
....
CD a.. 70
80
90
100
Project Haine-Skagway Hydroelectric
Work order ------rTr.,..,....-----...-..,.......,.,,...,.
Drawn_ I1H_ Checked DER Date 3/5/82
Sample NO. _..:.2 _____ ~ __ _
DRAWING NO. 0-9
!
'0 -
~
8
d
FINE AGGREGATE GRADATION
....
o
d
Size or opening in inches
~ o
d
....
~ o
50 ~-------T--------~--------r-------~--------~--------'
40~-------+--------~--------~------~--------~------~
30~--------~--------+---------~--------~--------~------~
i20~~ ~ ~-----Ij-----~------~
10 ~------~--------~--------~--------~------~~------~
o ~ ________ L-________ ~ ________ ~ ________ ~ ________ ~ ______ __
Pan No. K>O No. 50 No,30
Screen size
No. 16 NO.8 No.4
Screen % Retained
size Individual Cumulative
No.4 a 0
NO.8 10 10
No. 16 17 27
No. 30 17 44
No. 50 17 61
No. 100 16 77
Pan 23 100
Fineness modulus
I Percent sand (clean separation): 85
I (Screen sizes are based on square openings)
Project Ha i nes-Skagway Hydroe 1 ectri c
Work Order ___________ _
Location Borrow Area
Pit No. Test Pit 1, Sample 2
Elev. or Depth ft., From~ to _6_, 0 __ _
Drawn BH Checked ~ Date 3/8/82
DRAWING NO. D-10
... c::
~
COARSE AGGREGATE GRADATION
OOr-~----.--------r-------'--------'-----~
... : 20r-------~r---~--~r_------~~------~~------~
10
0 ~
No.4 3 in. ],In.
S 4
,lin 2 . 3in. 61n.
Screen size
Screen % Retained
size Individual Cumulative
6 in. 0 0
3 In. 0 0
, 112 in. 0 0
3/4 in. 9 +--fa 3/8 in. 31
No.4 60 100
Pon
Percent coarse aggregate = 15
(Screen sizes ore based on squort openings)
Project Haines-Skagway Hydroelectric
Work Order _______________ _
Location Borrow Area
Pit No. Test Pit L Sample 2
E lev. or Depth ft., From..2....&..-to 6. 0
Drown BH Checked .QI.!L Dote .lL!d82
DRAWING NO. 0-11
-.s::. .,.
°as :.
~
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"-4)
c: --c:
4)
(.) -4)
0..
100
90
80
70
60
50
40
30
20
10
o
o o
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#
I
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7
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Specific Gravity ,+4_. -4_
CD
#
Remarks: __________ _
SIEVE ANALYSIS
Screen Size
Q') 'it
# ~ to to
I
J
I r
I
I
Location Borrow Area
Pit No. Test Pit 2
Elevo or Depth,
--IN -
Ft., From 3 a To ____ 3...;5~-
: = It) CD
0
10
20
30 .l: .,.
0«;
:.
40 ~
oJ:)
"-4)
",
"-50 c
0
(.) -c: 60 G,)
(.)
"-4)
0.. 70
80
90
100
Pr~ect Haines-Skagway Hydroelectri
Work order _________ _
DrawnB.I:I.....-Checked...D.£.R... Date 3/5/82
Sample Noo __ 1L--____ ~ __ _
DRAWING NO. 0-12
FINE AGGREGATE GRADATION
Size or opening in inches
fB ,... (\J <n ,... rt) It) 0 -~ ~ ~ ~ 0 0 0
0 0 0 0 0 0
50
Screen % Retained
size Individual I Cumulative
40 No.4 0 0
NO.8 0 0
No. IS 1 1
No. 30 2 3
No. 50 5 8
30 No. 100 23 31
\ Pan 69 100 '! Finenesl modulus
'0 -r Percent sand (clean seporation)= 100 ! -\ I (Screen sizes are based on square openings) c
~ 20 ....
l.
Project Haines-Skagway Hydroel ectric
10 \ Work Order
Locotion BQrt::~:u~ 8rea ~ Pit No. Test Pit 22 SamQle 1
Elev. or Depth ft., From~ to 3.5
0
Pan No. 100 No. 50 No. 30 No. IS No.8 No.4 Drawn BH Checked I2E..lL-Dote .J.JlU82
Screen size
DRAWING NO. 0-13
-.s::
CI 'Q) • >.
.&:J
~
CD c: .... -c:
CD u ..
CD
Q..
100
90
80
70
60
50
40
30
20
10
0
o o
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o o
#
/'
~
/'
/'
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10
#
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Specific Gravity ,+4_, -4_
Remarks:
I
7
L
.---
I
7
I
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r"
I
SIEVE ANALYSIS
Screen Size
CD ..,.
# 1
7
I
I
I
.,/
....-' .---
CD
'" ro
7
/ ....
7
I
ro
/
I
7
/
/
/
/
7
........ /
/
/
7
./
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;/
Location Borrow Area
Pit No. Test Pit 2
Elev. or De~t~,
Ft.,From . To 5.0
--IN = = -ro to
0
" 1/
II
II 10
II
I
I 20
I
I
I
I
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30 .E
at
'CD •
I 40 >.
.&:J
/ I
/
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~
I 50 a
0
I u
I -c:
Ii 60 CD u
~
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/ Q..
/ 70
80
90
100
Pr~ect Haines-Skagway Hydroelectri
Work orde r ___ ---"-=-= _______ ..,,.-
Drawn ~ Checked DER Date 3/5/82
Sample N.o. _---'-2~ ___ ----: ___ _
DRAWING NO. D-14
FINE AGGREGATE GRADATION
Siz. or opening in inches
en C\I 10 ,... It) en ,...
10 0 'It S 0 0 ~ 0 ~
d c;j d c;j 0 c;j
50
40~------~---------+---------r--------;---------+-------~
30 ~--------~--------~------~~--------~--------r-------~
~ c:
'0 -f
C / ....
8 20 ~--------+---------~~~/~----r---------+---------~--------~ ~IO /v
~~V
o L-________ ~ ________ ~ ________ ~ ________ ~ ________ ~~ ______ __e
Pan No. JOO No. 50 No. 30
Screen size
No. 16 No.8 No.4
Screen
size
% Retained
Individual Cumulative
No.4 0 0
NO.8 22 22
No. 16 22 44
No. 30 24 68
No. 50 19 87
No. 100 7 94
Pan 6 100
Fineness modulus
I Percent sand (clean separation)= 20
l (Screen sizes are based on square openings)
P . tHaines-Skagway Hydroelectric
rOJ'c
Work Order __________________ _
Location Borrow Area
Pit No. __ T--,e....;;s....;;t--,-P..:....i t..::........:2:......,'---"-S..:;,;am""'p .... l;....;;e;........;;;2 __
Elev. or Depth ft., From~ to 5.0
Drawn .§_H_ Checked ~ Dat. 3/8/82
DRAWING NO. D-15
! ·0 -.,
t--c:
'" (.)
t-.,
a..
50
40
30
20
10 /
o
No.4
COARSE AGGREGATE GRADATION
V
/
3 in.
S
/
din 4 .
Screen size
\
31n. 61n.
Screen % Retained
size Individual Cumulative
6 in. a a
3 In. 26 26
11/2 in 26 52
3/4 in. 27 79
3/8 in. 14 93
No.4 7 100
Pan
Percent coarse aggregate = ~n
(Screen sizes are based on square openings)
ProjectHa i nes-Skagway Hydroe 1 ectri c
Work Order ________ _
Location Borrow Area
Pit No. Test Pit 2. Samp] e 2
Elev. or Depth ft., From.iL.L to 5. 0
Drawn BH Checked JlE.!L Date J.l.ffJL82
Lob. Sample No. -=2 ______ _
DRAWING NO. 0-16
-.r:.
0 'Ii • >.
.0
"-Q)
c: --c:
Q)
(.) ..
Q)
Q..
o o
C\I
#
100
90
80
70
60
50
40
30
20
10
0
o o
#
-/ -
./
o
I{)
#
-4
/
/
/
/'
1* ~
/
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/
/
/'
/
.....
Specific Gravity ,+4_, -4 __
c.D
#
7
/
/
/
/
7
7
/
Remarks: ___________________ _
7
I
7
I
7
/
SIEVE ANALYSIS
Screen Size
Q) '>:t
# ~I! rt)
/
I
/
/
/
/
/
I
/
/
/
/
/
1/
/
/ T
/ /
/
/
/
/
/' 7
/' 7
I
/
/
/
/
/
/
Location Borrow Area
Pit No. Test Pit 3
Elev. or Depth,
If)
/
V
7
Ft.,From 30 To 3 5
--IC\I = = -rt) c.D
A 0
//
//
/
/
/ 10
/ /
/ /
/ 20
-
/
/
30 .r:.
0
'iii :.
40 >.
.0
"-Q)
en
"-50 0
0
(.) -c:
60 Q)
(.)
"-Q)
Q..
70
80
.
90
100
Pr~ectHaines-Skagway Hydroelectric
Work order ___ ---;:::-;:::-";--_~,..",...,,....,..,..
Drawn ~ Checked DER Date 3/5/82
Sample No. __ ]L...-___ ~ __ _
DRAWING NO. 0-1 7
50
40
30
"i
.~ o
f -c:
~ 20 ...
.f
10
o
en
It)
0
0
d
/
Pan No. 100
FINE AGGREGATE GRADATION
S iZI or openinO in inches
C\I ,... rt'I en ,...
~ 'lit ~ 0 0
d d d 0
v ~
,/ V
No. 50
/
No. 30
Screen size
1\
No. 16 No.8
It)
~
0
Screen % Retained
size Individual I Cumulative
No.4 0 0
No.8 24 24
No. 16 L~ 5L
No. 30 22 14
No. 50 16 90
No. 100 5 9!J
Pan !J 100
Fineness modulus
Percent sand clean separation = 43
(Screen sizes are based on square openings)
Project Ha i nes -Skagway Hyd roe 1 ect ri c
Work Order _________ _
Location Borrow Area
Pit No. __ T~e"",,,s:....l<t;......:...P ...... i t",---"3,-,,~S,,,",a m.!!lD:<.J1 ..... e .......... 1 _
Elev. or Depth ft., Froml..:.Q.... to 3.5
No.4 Drawn BH Checked ~ Date 3/8/82
DRAWING NO. D-18
~
~
"0 -..
~ -c: ..
0
~ ..
11.
COARSE AGGREGATE GRADATION
50
40
30
/ ~ ~ \ 20
10
o
No.4 3 in.
S
~in.
4
Ilin.
2
Screen size
3in. 61n.
Screen 0/0 Retained
size Individual Cumulative
6 in. a a
3 In. a a
I 1/2 in. 26 26
3/4 in. 23 iN
'3/8 in. 28 77
No.4 ~j 100
Pan
Percent coarse aggregate = 57
(Screen sizes are based on squart openings)
Project Ha i nes-Skagway Hydroel ectri c
Work Order ________ _
Location Borrow Area
Pit No. __ T.;..:e::...::sc..:::t---,-P 1.:....:· t::........:::.3 ...... , .....::S~a~m~p l~e"---O!:.l
Elev. or Depth ft., Fro~ to 3.5
Drawn BH Checked ~ Oat, 'ii..5.L82
DRAWING NO. D-1 9
-.£:
at 'as •
""" ..Q ...
Q)
c: --c:
CD u ...
CD a.
100
90
80
70
60
50
40
30
20
10
0
o o
N
#
--
o o
:#
~
./'
/
o
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#
l/
./
/
~
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#
II
/
/
/
/
./' ---
# '" Specific Gravity ,+4_. -4_
CD
#
I
I
/
I
/
--;.;;'
C7
./'
/
Remarks: __________ _
/
../
SIEVE ANALYSIS
Screen Size
a> v
# ~ rt') rt>
I
I
I
I
/
/
/
7
/
/ /
/ /
/'
./'
/
./' / ,,-7
/
/
/
/
/
/
/
V
Location Borrow Area
Pit No. Test Pit 4
Elev. or Depth,
Ft.,From 3.0 To 3.5
--IN : : -rt> <D
/ 0
;7
//
/7
//
// 10
/
1/
I I 20
I I
30 1:
at
I
II
'iii •
/ 40 """ ..Q
/ ...
Q)
rn ...
50 0
0
I u
I -c: 60 CD u ...
Q) a. 70
80
-
90
100
Pr~ectHaines-Skagway Hydroelectric
Work order ___ --::::-::-=: ___ .,...---, ___
Drawn...!ilL-Checked DER Dote 3/5/82
Sample No. _....Jl"-____ ..:..-__ _
DRAWING NO. 0-20
FINE AGGREGATE GRADATION
Size or opening in inches
fR I'-N (J') I'-~ 1.0 0 N .". (J') CD 0 0 0 0 Q
0 0 0 0 0 0
50
40 ~--------~--------~---------~---------1----------+_-------~
30 ~------~---------+---------r--------;---------+-------~
-
o L-________ L-________ L-______ ~L ________ ~~ ______ ~ ________ ~
Pan No. 100 No. 50 No. 30
Screen size
No. IS NO.8 No.4
Screen 0/0 Retoined
size Individual Cumulative
No.4 a a
No. s 24 24
No. IS 27 51
No. 30 24 75
No. 50 13 88
No. 100 7 95
Pan 5 100
Fineness modulus
r Percent sand (clean separot ion)= 25
I {Screen sizes are based on square openings)
Project Haines-Skagway Hydroelectric
Work Order _________________ _
Location Borrow Area
Pit No. Test Pit 4, Sample 1
Elev. or Depth ft, From~ to 3.5
Drawn ~ Checked ~ Date 3/8/82
DRAWING NO. 0-21
"C
! ·0 -iii ... -c
:'J ...
iii
0..
COARSE AGGREGATE GRADATION
50
40
30
20
V
~
10
o
No.4 3 in 8 .
V
/
~in.
4
/
Screen size
1\
\
.\
31n. 61n.
Screen % Retained
size Indhlldual Cumulative
6 In. 0 0
3 In. 17 17
I 1/2 in. 33 50
3/4 In. 22 72
3/8 in. 18 90
No. 4 10 100
Pan
Percent coarse aggregate = 75
(Screen sizes are based on square openings)
Project Haines-Skagway Hydroelectric
Work Order ________ _
Location Borrow Area
Pit No. Test Pit f. .• SamD] e 1
Elev. or Depth ft., From ~ to 3. 5
Drawn BH Checked ..QI!L Date 3/5/82
DRAWING NO. 0-22
l:
01 'a:; :.
>.
..Q
~
CD
.5 --c
CI)
(,) -CD a..
100
90
80
70
60
50
40
30
20
10
o
o o
C\I
#
o o
#
7
I
//
rT7 v
/.-'1
//
//
o
10
#
I
I
/
I
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/ /
7
/
/
I
/
I
/
/
o
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#
I
/
S 'f' G .. • peci IC ravity,+4_,-4_
Remarks:
CD
#
/
/
/
/
/
/ /
/ /
/
I
/
/
/
/
SIEVE ANALYSIS
Screen Size
Q) ~ = -# ~ r() r()
7
/ /'
/ ./"
;;-/
/
/ / I
/ /
7 /
/'
/'
./
/ I
!I
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I
Locati on _.,...:B:....:o:....,r_r.,;;,o~w..,....A;....r;...;e:...:a=--_
Pit No. __ T_e_s_t_P_it_5 __ _
Elev. or Depth I
Ft. t From 2 5 To ___ _
IC\I = -ro CD
0
10
20
30 l:
01
'Ci :.
40 >.
..Q
~
CD
",
~
50 g
(,) -c 60 CI)
(,)
~
CD a.. 70
80
90
.
100
Pr~ectHaines-Skagway Hydroelectric
Work order ___ --:::-:=-;:: __ ---,~,....,..",.
Drawn ~ Checked DER Date 3/5/82
Sampl e N.o, _....-..!1'--___ ~ __ _
DRAWING NO. 0-23
m o o
d
FINE AGGREGATE GRADATION
.....
o
d
Size or openinQ in inches
50 ~-------,--------~--------~--------.---------~------~
40~-------+---------r--------r--------+--------~------~
10 ~-------+--------~--------~-------+--------~~----~
OL-------~--------~---------L--------~--------~------~
Pan No. 100 No. 50 No. 30
Screen size
No. IS No.8 No.4
Screen % Retained
size Individual Cumulative
No.4 a a
No.8 11 11
No. 16 13 24
No. 30 19 43
No. 50 26 69
No. 100 19 88
Pan 12 100
Fineness modulus
I Percent sand (clean separation)= 80
I (Screen sizes are based on square OPenings)
Projlct Haj nes-Skagway Hydroe 1 ectri c
Work Order ________ _
Location Borrow Area
Pit No. _-..:T .... e_s ..... t.....,P ...... i ..... t ......... 5 .......... S"'a=m~D..L..:l e ......... lo.-
Ellv. or Depth ft., From~ to ___ _
Drawn BH Checked ~ Dati 3/8/82
DRAWING NO. D-24
-..c:
0
'is :.
>.
~
~ co
,5 .... -c co
0 -co a..
100
90
80
70
60
50
o o
'" #
40
30
20
10
o
I
I
I
o o
#
I
7
I
/
7
o
10
#
I ./" v-
I
#. ~
/'
o
f'I')
#
Specific Gravity ,+4_, -4_
Remarks:
#
SIEVE ANALYSIS
Screen Size
Q) ~
~ # It>
E
Location Borrow Area
Pit No, Test Pit 5
: IN
It> --
Elev, or Depth:1
Ft., From 3. ~ To ___ _
= :
It> CD
0
10
20
30 l: at 'cp :.
40 >.
~
~ co en
~
50 0
0
0
+-c
60 co
0
~ co a..
70
80
90
100
Pr~ect Haines-Skagway Hydroelectric
Work order _________ _
Drawn lliL--Checked...D..ER. Date 3/5/82
Sample N.o, --~2~--~---
DRAWING NO. D-25
70 FINE AGGREGATE GRADATION
Size or opening in ind1es
~ ,.... C\I en ,.... rc') 10 8 -fj .-~ !! 0 0
0 0 0 d 0 d
50
Screen '-0 Retained
size Individual Cumulative
40 No.4 0 0
No. 8 0 U
No. 16 u u
No. 30 1 1
No. 50 b I
30 No. 100 z.:! .:IU
"i \ Pan 70
c: Fineness modulul ·s -l! L Percent sand (clean separation)= 100 I
1: r\ I (Screen sizes are based on square openings) I
~ 20
~
8.
Project Ha i nes-Skagway Hydroe 1 ectri c
10 \ Work Order
Location Borrow Area ~ Pit No. Test Pit 5 ~ Sample 2
Elev. or Depth ft., From~ to 0
Pan No. 00 No. 50 No. 30 No. 16 No.8 No.4 Drawn BH Checked ~ Oote 3/8/82
Screen size
DRAWING NO. D-26
-..c
01 'il :.
:>. ..a ...
cal c:: --c::
Q)
(.)
~
Q) a..
0 0 0 0 0 (\.I 0
# 10 If')
100 # # #
......-'
~
90 -----~
80
70
60
50
40
30
20
10
SIEVE
Screen
CD v
# ~
U>
# --
ANALYSIS
Size
/
/
/
/
/
(X) ......
If')
I
I
I
I
-v = ...... -1(\.1 If') -= :
0
I
10
r
I
20
t
30 -01
'Qi I
:.
40 :>. ..a ...
cal
I/) ...
50 g
(.) -c::
60 Q)
(.) ...
cal a..
70
I
80
90
0 ~--~----~--~----~---L----4---~----~--~~---L----L----JIOO
S T "-4 peci Ie Gravity ,+4_, - _
Remarks:
Location Borrow Area
Pit No, rest Pit 5
Elev, or Depth,
Ft., From 4.5 To ___ _
Pr~eet Haines-Skagway Hydroelectri
Work order _________ _
Drawn -ID:L Checked DER Date 3/5/82
Sample No, _3"--____ ~ __ _
DRAWING NO. 0-27
, 90
m
8
0
50
\
\ 40
\
\
\
\
10
o
Pan No. 100
FINE AGGREGATE GRADATION
Size or opening in
..... --q
0
No. 50
N
rt)
~
0
No. 30
Screen size
inches
~
0
0
No. IS
.....
S
0
No.8
&0
!!
0
Screen % Retained
size Individual Cumulative
No.4 a a
No.8 a a
No. IS 1 1
No. 30 3 4
No. 50 3 7
No. 100 3 10
.... Pan 90 100
Fineness modulus
Percent sand (clean separat ion): 99. 6
(Screen sizes art based on square openings)
Project Ha; nes -Skagway Hydroe 1 ec t ri c
Work Order ________ _
Location Borrow Area
Pit No. __ ...!.T-=e~s t~P...!.i....!<.t_5~'2......::::S:.l:!.a!.!.!.mpt::...l!..l;e~3
Elev. or Depth ft., From~ to __ _
No.4 Drawn BH Checked ..QI!L Dote .2.i..Y82
DRAWING NO. 0-28
.... .c at 'as
)I:
>-.Q
....
Go) .: .....
1:
Go)
0 ...
Go)
0...
o o
C\I
#
100
90
80
70
60
50
40
30
20
10
o
./
./
./
o o
#
I
II
!
I
o
It)
#
f
I
{
1'-~
I
I
o
~
#
/
17
I
!
Specific Gravity ,+4_, -4_
#
/
/
/
/
Remarks: ____________________ __
SIEVE ANALYSIS
Screen Size
IX) v r-#
i-
I
f'C')
-v .....
f'C')
Location Borrow Area
Pit No. Test pit 6
Elev. or Dep.th...,
Ft., From 2. I To 3. 5
= IN --
-"-t-"
I
= -rt) CD
0
10
20
30 1: at
'iD
)I:
40 >-.Q
....
Go)
en ....
50 Q
0
0 .... c: 60 Go)
0
....
(I) a.. 70
80
I
90
100
Pr~ectHaines-Skagway Hydroelectric
Work Qrder ------,.n-n--...,..,...,. .................
Drawn I:S_H __ Checked OER Date 375782
Sompl e N.o. __ 1=--_____ ..:..-___ _
DRAWING NO. 0-29
l
'6 -f -c:
FINE AGGREGATE GRADATION
~ g
d
.....
o
d
Size or opening in inches
~ o o
50 .-------_T--------~--------r_------_T--------~------_.
40~-------+--------~--------~-------+--------~------~ V
/ 30~----~~~--------~~~----~--------~------~~------~
~ 20 ~~~----r---------~----~--r---------~------~~------~ ~ \
10~----~-----+----~·~~----~----~----~
OL-----~ ___ _L ___ ~ ____ ~==== __ ~----~
PCI1 No. k)() No. 50 No. 30 No. 16 No.8 No.4
Screen size
Serlin 0/0 Retained
size Individual I Cumulative
No.4 a a
No. 8 a a
No. 16 1 1
No. 30 13 14
No. 50 40 54
No. 100 36 90
Pon 10 100
Fineness modulus
I Percent sand (clean seporation):: 100
I (Scre.n sizes are based on square openi ngs )
Project Haines-Skagway Hydroelectric
Work Order _______________ _
Location Borrow Area
Pit No. Test Pit 6, Sampl e 1
Elev. or Depth ft., From~ to 3.5
Drown BH Checked ..Qf!L Date 3/8/82
DRAWING NO. 0-30
-.s::::
at
'is • >-.0 ...
CD ,S --c:
CD u -Q) c..
100
90
80
70
60
50
40
30
20
10
o
o o
N
#
./'
/'
;7
o o
#
o
10
# #
Specif ic Gravity )*4_, .!4 4_
Remarks:
#
SIEVE ANALYSIS
Screen Size
CD 'I;f'
~~ =If: ro
Location Borrow Area
Pit No. Test pit 6
: IN -ro -
i
Elev. or Depth J
Ft., From 3.9 To _4",,-,....,5,,-' __
= -ro CD .' 0
10
20
30 1: at 'Q) •
40 >-.0 ...
CD en ...
50 0
0 u -c: 60 Q) u ...
CD c.. 70
80
90
100
Pr~ectHaines-Skagway Hydroelectric
Work order _________ _
Drawn.li.t!..-Checked DER Date 3/5/82
Sample N.o. _...::2=--____ ..:.-__ _
DRAWING NO. D-3 1
"I ·0 -f -c:
~ 97
fB
8
d
FINE AGGREGATE GRADATION
,....
o
d
Size or opening in inches
(J) • o
d
,....
$ o
50 ~-;------~--------r---------~--------~------~~------~
40~--~---1--------~--------~--------4---------+-------~
30 ~----~--~--------~--------~--------r_------~r_------~
~ 20 r_-----+--~--------~--------r_--------r_------~r_------~
'-8.
10 1------++-\ -f----I-----+-------+-------i
oL-----~======~====~~==~L_----~----~
Pan No. 00 No. 50 No. 30
Screen lize
No. 16 No.8 No.4
Screen % Retained
size Individual Cumulative
No.4 a a
No.8 a a
No. 16 a a
No. 30 1 1
No. 50 1 (
No. 100 1 3
Pon 97 100
Fineness modulus
Percent sond (clean separation):::
(Screen sizes are based on square OPenings)
Project Ha i nes-Skagway Hydroel ectri c
Work Order _______________ _
Location Borrow Area
Pit No. Test Pit 6, Sample 2
Elev. or Depth ft., From..l.:2.... to 4.9
Drawn BH Checked ~ Date 3/8/82
DRAWING NO. 0-32
-.c.
at 'CD
)I
>.
-'l
"-CD c:: --c::
4P
() ...
4P a.
100
90
80
70
60
50
o o
N
#
40
30
20
10
0
./
./
o o
:1:1:
II
---'
/
./'
7
/
o
LO
#
I
~
7
7
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I
/
/
o
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#
./
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,
Specific Gravity ,+4_, -4_
/
/
/
/
/
/
/
..--' --
Remarks: ______________________ _
/
/
SIEVE ANALYSIS
Screen Size
Q) o:t
# ~~ .." rc')
/
/
I
7
7
7
-;
/
I
7
/
-'
7
/
1/
/"
./
V
../"
./'
/
/
/
/
/
, /
/
/
It'
Location Borrow Area
Pit No. Cut Bank 1
I
/
/
Elev. or Depth 0
Ft., From 2. To 3.0
--IN : : -.." CD
0
A
/I
1/ 10
I
I
20
-30 .c.
Ct 'CD
7 )I
I I
I 40 >.
-'l
I "-
I CD en
"-
1 50 a
0
() -c::
60 4)
()
"-CD a.
70
80
90
100
Pr~ect Haines-Skagway Hydroelectri
Work orde r _____ -:=-=,--__ -..".~...,."....,.
Drawn ~ Checked DER Date 3/5/82
Sample N,o. -..Il'---____ ~ __ _
DRAWING NO. D-33
50
40
30
i c:
'6 -f -c:
~ 20 ...
!.
10
o
FINE AGGREGATE GRADATION
Size or opening in
~ f'-t\J
rt) 0 t\J 0 0 0
0 0 0
/ \
V
l7
Pan No. 100 No. 50
\
No. 30
Screen size
inches
(1) ,....
V (1)
0 Q
0 0
V 1\
No. IS No.8
It)
(I)
0
No.4
Screen % Retained
size Individual I Cumulative
No.4 a a
No. 8 18 18
No. 16 13 ::n
No. 30 12 43
No. 50 2~ /l
No. 100 18 89
Pan 11 IOU
Fineness modulus
Percent sand clean separation:: 28
(Screen sizes ore based on square openin s)
P . t Haines-Skagway Hydroelectric rOJlc
Work Order _________ _
Location
Borrow Area
Pit No. __ C_u_t_Ba_n_k_l_, _S_a_m..;..p_, e_l_
Elev. or Depth ft., From~ to 3. a
Drawn BH Checked Date 3/8/82
DRAWING NO. D-34
-,;J
~
0 -If ... -c:
If
" ...
If
Il..
COARSE AGGREGATE GRADATION
50
40
30
20
V V
10
o
No.4 3 in.
S
II
/
~in.
4
/ 1\
Illn.
2
Screen slzt
\
3in. 6in.
Screen 0/0 Retained
size Individual Cumulative
6 In. 0 0
3 In. 0 0
11/2 in 46 46
3/4 in. 27 73
3/8 in. 16 89
No.4 11 100
Pan
Percent coarse aggregate = 72
(Screen sizes are based on .qua .... openings)
Project Ha i nes-Skagway Hydroe 1 ectri c
Work Order ________ _
Location Borrow Area
Pit No. Cut Bank 1, Sample 1
Elev. or Depth ft., From LL to 3.0
Drawn ~~_ Checked ~ Datt 3/5/82
DRAWING NO. D-35
-.c
0-'iii :. ,..
..Q
"-II)
c --c
II)
<J ...
II) a..
100
90
80
70
60
50
40
30
20
10
0
o o
C\I
#
..-
o o
#
~
/'
/"
---
o
10
#
7
I
7
/"
./'
I
/
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#
I
/
./
1* *4 Specific Gravity ,+4_, -4_
Remarks:
#
/
/
I
I
I
/
./
./
/'
./
/'
/
SIEVE ANALYSIS
Screen Size
CD v
# ~
I
/
/
I
/
/
I
/
/'
/'
./
./
v
ro
7
/
/'
ro
/
/
7
./ /
/
/
7
7
II
/
/
/
/
Location Borrow Area
Pit No, Cut BanK L
Elev, or Depth
: IN --
/
/
/
/
/
/ /
/ I
I
I
/
f
. Ft., From To ___ _
: :
It) <0
/I {)
//
//
/
/ / 10
/ /
/ /
/
/ 20
/
/
I 30 1:
CIt
'iii :.
40
,..
..Q
"-II)
(I)
"-50 CJ
0
<J -c
60 II)
<J
"-II)
Q..
70
80
90
100
Pr~ect Haines-Skagway Hydroelectri
Work order _________ _
Drown ~ CheckedDER Date 3/5/82
Sample N.o, _-..c.1 ____ --:.-__ _
DRAWING NO. D-36
~
'0 -lP
fR o o o
FINE AGGREGATE GRADATION
I"-
o o
Size or opening in inches
~ o
I"-
Q') q o
50 ~--------__ --------~--------r---------~--------~-------,
40~------~---------+---------r--------~--------+-------~
30~--------~--------~--------~--------~--------~------~
; ~'-
8 20 ~--------~------~~--------~--------r---------r~r-------~
l
10~------~V~------+-------~-------+--------~--4-~
V
O~--------~--------~--------L---------L---------~------__
Pan No. 100 No. 50 No. 30
Screen aize
No. 16 No.8 No.4
Screen % Retained
size Individual Cumulative
No.4 0 0
NO.8 22 22
No. 16 22 44
No. 30 24 68
No. 50 21 89
No. 100 8 97
Pan 3 100
Fineness modulus
I Percent sand (clean separation)= 36
I (Screen sizes are based on square openi ngs )
Project Haj nes-Skagway Hydroel ectri c
Work Order _______________ __
Location Borrow Area
Pit No. Cilt Bank 2. Sample 1
Elev. or Oepth ft., From~ to 6.0
Orawn BH Checked ~ Oate 3/8/82
DRAWING NO. D-37
"'0
~
'0 -.,
~ -c: .,
0
~ .,
Q..
COARSE AGGREGATE GRADATION
50
40
30
20
~ /
10
o
No.4 3 in.
S
/ ~
~in.
4
Screen size
~
~
\
31n. 61n.
Screen 0/0 Retained
size Individual Cumulative
6 In. 0 0
3 In. 18 18
I 1/2 in 23 41
3/4 in. 27 68
3/8 in. IH H6
No. 4 14 IDO
Pan
Percent coarse aggregate = 64
(Screen sizes are based on .quare openings)
Project Ha i nes-Skagway Hydroel ectri c
Work Order ________ _
Location Borrow Area
P it No. _--.:C;:..:::u:....::;t.....;B~a::..:..n:..:.!k_2:...l...., ....:=S~a m~p~l~e---=-1
Elev. or Depth ft., From~to 6.0
Drawn BH Checked ..QI£L. Date .J.L]j82
DRAWING NO. D-38
-.c.
0»
'is :.
>-.Q ...
CD
,5 --c
CD
() -CD
Q..
o o
N
#
100
90
80
70
60
50
40
30
20
10
=
0
~
o o
#
./
/'
..,----
./
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II)
#
--
I
/
/
/
It-~
/
/
o
rt)
#
/ [I
/
Specif ic Gravity t + 4_ t -4_
I
7
I
7
I
I
I
/
/
/
/
/
/
Remarks: __________ _
SIEVE ANALYSIS
Screen Size
Q) q---IN :; :;
# ~ rt> rt> -rt> (/)
// 0
.//
/ //
/ ./ /
/ / 10
/ / /
/
/
I 20
/
/
7 L
/
30 l: at
'CD :.
/
./ 40 >-.Q
/ I
./
...
CD tn
/'
./
...
50 0
0
/ [7 ()
L -c
60 CD
()
/
...
CD
Q..
7 70
I
I
80
/
/
/ 90
/
/ ...
/
100
Location Borrow Area
Pit No, Cut Bank 3
Pr~ect Haines-Skagway Hydroelectri
Work order _________ _
Elev. or Depth ...
Ft., From 4.u To 5.0
Drown -.6.l::L CheckedIlER... Date 3/5/82
Sample No. _~l,--____ ~ __ _
DRAWING NO. D-39
FINE AGGREGATE GRADATION
Size or opening in inches
m l"-N en I"-rO 10 0 N ~ en m 0 0 0 0 q
0 0 0 d 0 d
50
40~------~--------+--------+--------+-------~------~
30~------~--------+--------+--------+-------~------~
'i
to I-------l---~/_I__~______+_~~_t_____;
l ~
10~------~~------~------~-------+--------+~--~--~
l_----,V
o L-______ ~~ ______ ~ ________ _L ________ ~ ________ ~ ______ ___
Pan No. 100 No. 50 No. 30 No. 16 No. 8 No.4
Screen lize
Screen % Retained
size Individual Cumulative
No.4 n n
No. 8 16 16
No. 16 22 38
No. 30 28 66
No. 50 20 86
No. 100 7 93
Pan 7 100
Fineness modulus
I Percent sand (clean separation): 53
I (Screen sizes are based on square openinQs)
Project Ha i nes-Skagway Hydroe 1 ectri c
Work Order _________ _
Location Borrow Area
Pit No. __ C.:..;u:.;...:t:.........=B.=.an:.:.:k~3....!.---:...Sa:;.:.m;.,!;p....;.1..:;.e_l::....-
Elev. or Depth ft., From~ to 5. a
Drawn BH Checked ....!2E1L Dotelf.]L82
DRAWING NO. D-40
-,;J
~ '0 -• ... -c .,
u ... • Cl.
50
40
30
20 /
10
o
No.4
COARSE AGGREGATE GRADATION
/
/
3 in 8 .
/ \
~in.
4
Screen size
\
\
31n. 6 In.
Screen % Retained
size Individual Cumulative
6 In. a I 0
3 In. a a
1112 in a a
3/4 in. 18 18
3/8 in. 38 56
No. 4 27 83
Pan 17 100
Percent coorse oggregote = 117
(Screen sizes are based on .quart openings)
ProjectHa i nes-Skagway Hydroe 1 ectri c
Work Order ________ _
Location Borrow Area
Pit No. Cyt Bank 3, Sample 1
Elev. or Depth ft., From~ to 5.0
Drawn BH Checked QIL Date ...JJ.JJ.J82
Lab. Sample No. _______ _
DRAWING NO. D-4 1
-.s::.
01
'is
~
>. ..a
....
CD c:: --c::
Q) u ...
Q) a..
100
90
80
70
60
50
40
30
20
10
0
o o
N
#
r-'
.-/
/'
o o
#
----'
I
7
7
.-/
I
I
I
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It)
#
7
7
7
/
/
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/
/
I
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It)
#
/
/
Specif ic Gravity )*4_ • .!I4_
U)
#
/'
/'
/'
/'
/'
.......
----
Remarks: ______________________ _
/'
SIEVE ANALYSIS
Screen Size
(I) v --IN = :
# It) It) -It) U)
/ 0
/ /l
/ /1
/ /
/ /
/ / I 10
1/ I
/'
20
I
I I
I
30 1:
t7t
'ji
~
40 >. ..a
I ....
Q)
7
/
/ :tf 7
/
/ I
In ....
50 0
0 u -c::
/' 60 Q)
u
/' ....
/' Q)
L a..
----7 70
----7
I
/ 80
il
/'
/' 90
/'
/
/
100
pr~ectHaines-Skagway Hydroelectric
Work order _____________ _
Location Borrow Area
Pit No. Cut Bank 4
Drawn ~ Checked DER Date 3/5/82
Sampl e N.o. __ =-1 _____ ..:..-__ _
Elev., or DeJ)thd Ft., From 5. To 6.0
DRAWING NO. D-42
· . ---
0'1
If)
0
0
d
50
40
30
10
o
Pan No. 100
FINE AGGREGATE GRADATION
Size or
I"-
0
d
/ 1\
No. 50
opening in inches
N
rt')
N
0
d
No 30
Screen size
0'1
V
0
0
No. IS
I"-
0'1
Q
0
~ ~
No.8
10 m
0
I Screen % Retoined
I size Individual Cumulative
No. 4 0 0
No. S 14 14
No. IS 9 23
No. 30 10 33
No. 50 37 70
No. 100 20 90
Pan 10 100
Fineness modulus
Percent sand (clean separation;: 32
(Screen sizes are based on square openings)
Project Haines-Skagway Hydroelectric
Work Order _________ _
Location Borrow Area
Pit No. _--,-C u_t_B_a_n _k _4--.:,,--,-Sa_m-,-p_l_e_1 _
Elev. or Depth ft., From ~ to 6.0
No.4 Drawn BH Checked ~ Date ...3.L.B.L82
DRAWING NO. D-43
"0
~ '0 -., ... -c .,
0 ... .,
a.
50
40
30
20 V
10
o
No.4
COARSE AGGREGATE GRADATION
II
/
:3 in.
S
/ 1\
~in.
4
\
Screen size
1\
3in. 61n.
Screen % Retained
size Individual Cumulative
6 In. 0 0
3 In. 0 0
11/2 in. 22 22
3/4 in. 44 66
3/8 in. 21 87
No. 4 13 100
Pan
Percent coarse aggregate = 68
(Screen sizes are based on .quart openings)
P . tHaines-Skagway Hydroel ectric rOJec
Work Order ________ _
Location Borrow Area
Pit No. __ C_u_t_Ba_n_k_4..;...' _S_a_m.:,...p ,_e_1
Ellv. or Depth ft., From i.:.Q.... to 6.0
Drawn BH Checked ~ Date ..1/.!iI82
DRAWING NO. 0-44
-.s:::.
0 '. J:
>. .c
'-.,
c: -1: .,
u ... .,
Q.
100
90
80
70
60
50
o o
(\j
#
40
30
20
10
o o
#
II
ill
I
/'
L
L/
.£/
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I
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'I
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1.0
#
II
II
II
II
71
77
/,
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o
fI')
#
II
/I
Specific Gravity,+4_,-4_
CD
#
/
L4'
A
/.
II
1/
1/
Remarks: ______________________ _
SIEVE ANALYSIS
Screen Size
CX) q-
# f't') fI')
/' ---" ./
/' ..--./
/' /' /' ..... ./ /'
I ./
/
//
//
//
#
I
I
I
I
J
I
I
Location Borrow Area
Pit No. Cut Bank 4
Elev. or Depth I
Ft., From 8.2 To 10.0
= = -f't') CD
0
10
20
30 .:E
0 'v
J:
40 >. .c ... .,
en ...
50 0
0 u -c:
60 .,
u ... .,
Q.
70
80
90
100
Project Ha i nes-Skagway Hydroe 1 ectri c
Work order ____________ _
Drawn ~ Checked DER Date 3/5/82
Sample No, _...:;2:....-____ '--__ _
DRAWING NO. 0-45
50
40
30
~ c
'0 -4> ...
'E
~ 20 ... .,
CL
10
o
V
Pan
FINE AGGREGATE GRADATION
Size or opening in inches
(J'I C\I 10 I'-ro (J'I
0 t\I v
0 0 0 0
0 0 b 0
/ ~ ~
No. 100 No, 50
'\
No, 30
Screen size
~
.
No,16
I'-10 (J'I CX) 0
0 0
Screen % Retained
size Individual Cumulative
No.4 () n
NO.8 8 8
No. 16 13 21
No. 30 15 36
No. 50 27 63
No. 100 24 87
Pan 13 100
Fineness modulus
Percent sand (clean separation); 96
(Screen sizes are based on square openings)
Project Ha i nes-Skagway Hyd roe 1 ect ri c
~ ~
Work Order _________ _
Location Bo rrow A rea
Pit No. _----.:C~u:..:::t--!::::B a~n.!.!:k:........!..4.L' -,S~a~m~p..!..:l e,=---!:2=--
E lev. or Depth ft., From ~ to 10. a
No,8 No.4 Drawn BH Checked ~ Date 3/8/82
DRAWING NO. 0-46
.......-. CLAV-.......... rlll----SILT ----II .... IIOt~----F-1 N-E __ -_--II-.... ::I ... ;~_S_A~~DIUM _~~~ COAR:;I:=FINE
W
N
fj)
W > 30 w
fj)
(j
Z -o z
o 60 (L
fj)
W
0:: cr o u
-f-
cr: w
Z
L...
I-
Z 20
'-'.J
U
0::
W
(L
SIEVE SIZE -NUMBER :3 " 200 100 50 30 16 8 4 1l
lOO.O
TP-1, S-2 PARTICLE DIAMETER IN MILLIMETERS
GRAIN-SIZE DISTRIBUTION CHART Triaxial Test Spec;menl ............................................................................ _
HAINES-SKAGWAY REGIONAL HYDROELECTRIC PROJECT Project No
Skagvlay, Alaska
for R.W. Beck and Associates, Inc.
l3ulk Sample 81-5165
'-'-_.. ------
~ ConverseWard DavIs Dixon Geotechnical Consultants
Drawing No
0-47
..oIIIl-CLAY -· ...... rll----SILT ----I ....... t----F-' N-E-----... -.... :::I ... :~_S_A~~D'UM ---1-1 ..... COAR=I:= FIN E
W
N
If)
uJ
> 30
Ll1 -
If)
(j
Z
0
Z
0 60 tl
If)
W
0::
0::
0
(j
Z
<t 40
I
I-
0::
W
Z
lL
I-
Z 20
uJ
(j
0::
liJ
tl
TP-2, S-2
Triaxial Test Specimen
---Bulk Sampl e
3 ..
200 100 50 30 16 8 4 18
PARTICLE DIAMETER IN MILLIMETERS
GRAIN-SIZE DISTRIBUTION CHART
HAINES-SKAGWAY REGIONAL HYDROELECTRIC PROJECT
Skagway, Alaska
for R.W. Beck and Associates, Inc.
i) ConverseWard DavIs Dixon Geotechnical Consultants
50.0 100.0
Project No.
81-5165
Drawing No.
D-48
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HAINES-SKAGt~AY REGIONAL HYDROELECTRIC PROJECT ProjeclNo ---Bulk Sample Skagway, Al aska 8 5165
for R.W. Beck and Associates, Inc.
~ ConverseWardDavlsDlxon Geotechnical Consultants D-49
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HAINES-SKAGWAY RElJIONAL HYDROELECTRIC PROJECT Project No
Bulk Sample Skagway, Alaska 31-5165
for R.W. Beck and Associates, Inc.
Drawing No. (i) ConverseWard DaVIS Dixon Geotechnical Consultants 0-50
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Bulk Sample HAIN -SKAGWAY REGIONAL HYDROELECTRIC PROJECT
Skagway, Alaska
PrOject No.
81 5165
for R.W. Beck and Associates, Inc.
~ ConverseWard DaVIS Dixon Geotechnical Consultants 0-51
APPENDIX E
SEISMIC REFRACTION SURVEY
E.l GENERAL
A sei smi c refract i on survey was conducted as part of the subsu rface
exploration program. A total of 5,740 lineal feet along 12 separate
lines, SL-l through SL-12, was completed in preliminary Phase II Study.
The major portion of the seismic refraction field work was completed be-
tween August 22 and September 14, 1981. An additional seismic refraction
traverse, line SL-12 was completed December 1, 1981.
Seismic refraction lines SL-1 through SL-3 were completed in the area of
powerhouse alternative 2. Seismic refraction lines SL-4 and SL-12 were
completed in the area of powerhouse alternative 1, while SL-l1 was com-
pleted in the area of powerhouse alternative 3. Seismic refraction
lines SL-6 through SL-10 were completed in the area of the proposed dam
site and SL-5 was located in a proposed spillway area. The locations of
the various seismic refraction lines are shown on Drawings 3, 5 and 7.
The results of the survey are presented on Drawings E-1 through E-3.
The purpose of the seismic refraction survey was to determine the depth
to various velocity layers, particularly bedrock.
E.1.1 Personnel and Equipment
The geophysical field crew consisted of a principal geologist/geophysi-
cist and two staff geologists along with an engineer furnished by R. W.
Beck and Associates, Inc. The principal geologist/geophysicist super-
vised and assisted in all phases of the field operations and performed
interpretation of the geophysical data.
Converse Consultants, Inc.
2
The seismic recelvlng and recording equipment consisted of electromag-
netic, induction type Mark Products, Model L-IO, 8-hertz geophones
spaced at intervals along the multiconductor geophone cable. This cable
was coupled to a 24-channel SIE model RS44A amplifier and a SIE model
R-6B recording occillograph. This system has a separate recordi ng
camera which produced permanent photographic records.
The location and ground surface elevations along the seismic lines were
determined by Tryck, Nyman & Hayes of Anchorage, Alaska.
E.1.2 Field Procedures
Seismic energy was produced by the detonation of small two-component ex-
plosive charges. Charges were generally located at the ends and mid-
points on the line. In the areas where bedrock was interpreted as being
relatively deep, additional shot points were located beyond the ends of
each line in order to detect and/or extend the deeper refracting layers.
Exp10sive charges varied in weight from one-third to two pounds and were
buried in shallow, hand-dug holes ranging in depth from two to four
feet. The explosives were detonated using special seismic electrical
blasting caps. A suitable length of shooting wire was utilized to
afford safety to the man detonating the charge. The energy released by
the explosives was detected by vertically oriented geophones fitted with
a spike for coupling with underlying soil.
E.1.3 Discussion of Results and Interpretation
Compressional wave velocities and the depth to the various subsurface
velocity layers under the sites were evaluated by plotting the first ar-
rival times of the seismic energy with respect to the distance between
the explosive charge and the various geophones. Interpretive profiles
of the subsu rface velocity 1 aye rs for each sei smi c 1 i ne are shown on
Drawings E-1 through E-3. The ground surface shown on the seismic pro-
files is based on elevations furnished by Tryck, Nyman & Hayes of An-
chorage, Alaska.
Converse Consultants, Inc.
3
In general, the seismic interpretation indicates two or three subsurface
velocity layers. The upper velocity layer ranges between 500 feet per
second and 1,200 feet per second and is interpreted as representing the
near su rface loose soil 1 ayer and forest duff. The i ntermedi ate vel oc-
ity layer, where present, ranges in velocity between 1,700 feet per sec-
ond and 6,600 feet per second. This velocity layer is interpreted as
representing unconsolidated overburden materials. The third and/or
deepest velocity layer ranges in velocity from 6,250 feet per second to
16,600 feet per second and is interpreted as representing bedrock.
Seismic lines SL-l through SL-3 were located in the area of alternative
powerhouses 1-2 and 2-2. The individual lines ranged in length from 525
to 625 lineal feet and totaled 1,700 lineal feet. The resulting seismic
profiles are characterized by three to four velocity layers. The upper
1 ayer is characteri zed by a velocity of 500 feet per second and ranges
in thickness from approximately five feet to ten feet. This upper velo-
city layer is interpreted as representing the near-surface loose soil
layer and forest duff materials. The intermediate layer is character-
ized by velocities ranging from 1700 feet per second to 1,900 feet per
second. The intermediate velocity layer ranges in thickness from a few
feet upwards of 100 feet. This unit is interpreted to be unconsolidated
and relatively loose unconsolidated overburden soils. An additional
intermediate layer is interpreted near the lower portion of seismic
refraction lines, SL-l, SL-2 and SL-4. The velocities of this layer
range from 3,000 feet per second to 4,550 feet per second. This velo-
city layer is interpreted as representing unconsolidated overburden
material, however, denser and/or with higher moisture content. The
deepest velocity layer at the site is represented by velocities ranging
between 9,500 feet per second and 12,000 feet per second and is inter-
preted as representing bedrock.
Seismic refraction lines SL-4 and SL-12 were completed in the general
area of alternative powerhouse 1. The resulting profiles indicate a two
to four velocity layers. A surface velocity layer is presented along
the entire length of the lines and is represented by velocities ranging
between 500 feet per second and 1,000 feet per second. This velocity
Converse Consultants, Inc.
E-4
layer is interpreted as representing the near surface loose soil and
forest duff layer and is a few feet in thickness. Along the entire
length of seismic refraction line SL-4 and the downhill portion of
SL-12, an intermediate velocity layer is present. This layer generally
ranges in velocity between 3,000 feet per second and 3,300 feet per
second and is interpreted as representing a somewhat denser material
and/or a higher moisture content. At the downhill end of seismic re-
fraction line SL-12, an underlying velocity layer of 5,500 feet per
second is indicated. This layer thickens toward the Taiya River and is
interpreted as presenting denser and possibly water saturated sediments.
The deepest velocity layer along the two seismic lines ranges in veloc-
ity from 9,785 feet per second to 11,000 and is interpreted as repre-
senting bedrock. At the uphill end of seismic line SL-12, an inter-
mediate velocity layer of 6,250 feet per second correlates in boring DH
112 with more weathered and fractured rock.
Seismic refraction line SL-5 was located at the left abutment alterna-
tive spillway location. The seismic line was 275 lineal feet in length.
The resulting profile is presented on Figure E-1. The subsurface seis-
mic profile at the proposed spillway location consists of two velocity
layers. The upper layer is characterized by a velocity of 1,000 feet
per second and ranges in thickness from approximately three to seven
feet. This velocity layer ;s interpreted to represent the near surface
loose soil layer and forest duff materials. The underlying velocity lay-
er ranges from 13,350 feet per second to 16,600 feet per second and is
interpreted to represent bedrock. The difference in bedrock velocities
may represent a change in rock quality, such as the degree of fractur-
ing or joint spacing.
The general area of the proposed dam site was explored by seismic lines
SL-6 through SL-10. The individual lines ranged in length between 275
and 550 lineal feet and totaled 2,440 lineal feet. The resulting pro-
fil es of these sei smic 1 i nes are shown on Drawings E-2 and E-3. The
upper velocity layer is represented by velocities ranging between 1000
feet per second and 1200 feet per second and is interpreted as repre-
senting the near surface loose soil layer and forest duff materials.
The thickness of the upper velocity layer ranges from less than one foot
Converse Consultants, Inc.
E-5
to a maximum on the order of 15 feet. In general, immediately below the
surface velocity layer is a higher velocity layer interpreted as bed-
rock. This lower velocity layer is represented by velocities ranging
from 11,765 feet per second to 16,600 feet per second. An intermediate
layer with a vel oci ty of 4550 feet per second was detected beneath the
upstream portion of seismic refraction line SL-6. This layer is inter-
preted as representing moderately dense overburden.
Seismic line SL-11 was located in the vicinity of alternative powerhouse
3. The resulting profile is shown on figure E-3 and indicates three
subsurface velocity layers. The upper velocity layer, ranging between
500 to 1000 feet per second is interpreted to represent the near surface
loose soil and forest duff material and is only a few feet thick. An in-
termediate layer of 6600 feet per second, is interpreted to represent
unconsolidated alluvial materials which is probably relatively dense and
water saturated. This layer ranges in thickness from zero up to approx-
imately 95 feet. The deepest velocity layer, represented at 16,600 feet
per second, is interpreted to represent bedrock.
Converse Consultants, Inc.
300 300
500 FT/SEC
250
Intersection SL-3
200 200
150 150
14000 FT ISEC
100
50
12000 FT ISEC
o o
-5°ir------------------------------------------------------------------------~-50
SL-1
Intersection SL-1
Ground Surface
t:>t+.-109
200
.... rsTm SL-2 _-------:-=~~--_ ....... -----
200
1~
I-
W
W ...
~
~ 100
150
1900 FT/S~~,........._---
--...-' ---100
1700 FT/SEC
l-e > w
..J
W
50
~-------........... -
,r/// --------10900 FT/SEC 50
o~----------------------------------------------------------------~o
SL-3
50 o 50 100
HORIZONTAL SCALE IN FEET
NOTE: See Drawing 3 for location of seismic lines.
.... w
W
LI.
~
z
Q .... e > w
..J
W
200
150
100
50
o
Intersection SL-3
1700 FT/SEC
,r//
i='!:_::-::_:::"""_--_=~:;;...""/ ____ --_______ -~ ~
~ ----------9500 FT/SEC
3000 FT/SEC
_/
//--
200
150
100
50
o
-50~------------------------------------------------------------~-~
200
150
100
50
o
-50
Ground Surface
SL-2
1000 FT ISEC /_f",,,/r
:;.; --;...0" _-~?--/ 2000 FT ISEC
'i'/
'l /'l
// 500 FT/SEC :;.; /
r---~~------------~_~// ------------",'"
3300 FT ISEC ,,//'"
",.----------",/
10975 FT ISEC
",
" 11000 FT/SEC
200
150
100
50
-50
-100-'--------------------------------____________________________ -1--100
SL-4
SEISMIC REFRACTION PROFILES SL-1, SL-2, SL-3, & SL-4
Alaska Power Authority
HAINES-SKAGWA Y REGION FEASIBILITY STUDY
WEST CREEK PROJECT
for R. W. Beck and Associates. Inc.
Converse Consultants a.otechnlcal Engineering
and Applied Sciences
Scale NOTED Project No.
JAN 1982 81-5165
Prepared by BH Drawing No.
WSB E-1
ALO
West
850
!Ai Ground Surface
~ 800
~ t=-::=---__
z o
i=
~ 750 13350 FT ISEC w
oJ w
East
DH-101 850
800
750
700 -'-----------------------~700
North
750
I-700
w w ....
~
~ 650
i=
<C > W
oJ
W
000
SL-5
South
750
Ground Surface
700
12900 FT ISEC
650
600
550~------------------------------------------------------------L550
SL-7
50 o 50 100
! !
NOTE: See Drawing 3 for location of seismic lines. HORIZONTAL SCALE IN FEET
I-
W
W ....
;!;
z
0
i=
<C > w
oJ w
I-
W
W ....
;!;
z
0
i=
<C > w
oJ w
West
700
650
600
550
Ground Surface 1000 FT/SEC
----------;----
4550 FT/SEC
7-7-7---//
,/
./
/
/
/
15100 FT/SEC
D~102 East
700
\
\ --------
650
··600
500
~-----_________________________________________________ ~500
North
800
750
700
650
600
550
500
SL-6
Intersection SL-6
DH-:-103 -7 01+-104
--..;:, ____ ~ (PROJECTED 20~' DOWNSTREAM)
12100-14700 FT/SEC
""-....:
-...:-.;::
........ -....... _::::::"'1["----West Creek
South
1800
l750
700
-850
800
550
500
450 ~---------------------------------------------------------------------------~450
SL-8
SEISMIC REFRACTION PROFILES SL-5, SL-6, SL-7, & SL-8
Alaska Power Authority
HAINES-SKAGWA Y REGION FEASIBILITY STUDY
WEST CREEK PROJECT
for R. W. Beck and Associates. Inc. ----------------------------------------------------------
Converse Consultants Geotechnical Engineering
and Applied SCiences
Scale NOTED
Date JAN 1982
Prepared by BH
Checked by WSB
Approved by ALO
Project No.
81-5165
Drawing No.
E-2
North South
DH-
1
106
750 750
Ground Surface
>-
III
III
LL 700
~
z o
>= <C: > 650
III
...J
III
1200 FT/SEC
700
16600 FT/SEC
850
600~--------------------------------L800
>-
III
III
LL
~
Z o
>=
50
o
~ -50
III
...J
III
SL-9
Ground Surface
500 FT/SEC
------------
6600 FT/SEC
....-
/
1000 FT/SEC
50
",,;-........ -'"
/---16600 FT ISEC -50
/
-1oo-'----------------------"-~-----------'--100
SL-11
50 o 50 100
HORIZONTAL SCALE IN FEET
NOTE: See Drawing 3 for location of seismic lines.
>-
III
III
BOO
750
LL 700
~
z
Q
>-
<C:
~ 850
...J
III
800
West
Creek
BOO
DH-105
(PROJECTED 20' DOWNSTREAM)
\
( ound Surface 750
700
16100 FT/SEC
850
800
550~----------------------------------------------------------------------~550
>-
III
III
LL
~
z
Q
>-
<C:
>
III
...J
III
200
150
100
50
o
-50
SL-10
DH-111
(PROJECTED)
I~-----------~~------~~~ = = 3g0"Ff"/SEC = -=--= =-'/
700 FT/SEC
/
Ground Surface
DH-112
(PROJECTED)
,.,-,., --.-. --.
5500 FT ISEC / / 10800 FT/SEC
",/
.,,/' ., ,/' .
200
150
100
50
o
-50
-100-'----------~~~·-------------------------------------------------------L-l00
SL-12
SEISMIC REFRACTION PROFILES SL-9, SL-10, SL-11 & SL-12
Alaska Power Authority
HAINES-SKAGWAY REGION FEASIBILITY STUDY
WEST CREEK PROJECT
for R. W. Beck and Associates. Inc.
Converse Consultants Geotechnical Engineering
and AppHed Sciences
Scale NOTED
Date JAN 1982
Prepared by BH
Checked by WSB
Approved by ALO
Project No"
81-5165
Drawing No"
E-3
APPENDIX C
ENVIRONMENTAL INVESTIGATIONS
DANIEL M. BISHOP
ENVIRONMENTAL INVESTIGATION
~nvironaid
12175 Mendenhall Loop ROqd
JUNEAU. ALASKA 99801
907 789.9305
OF THE WEST CREEK HYDROELECTRIC PROJECT
J>repared for:
R.W. Beck & Associates
December 15, 1981
AUTHORSHIP AND ACKNOWLEDGEMENTS
The wildlife section of this report was completed under the direction of
O. Charles Walmo. Dr. Walmo presently resides in Boxeman Montana, after
retiring from Federal service as a research biologist. His varied and
extensive biological experience includes four years of wildlife work in
Southeast Alaska for the U.S. Forest Service. This work involved studies
of Sitka blacktail deer, and mountain goat habitats. Dr. Wallmo recently
edited the encyclopedic volume, Mule and Black~tailed Deer Distribution
and Habitats.
Steve Jacoby, who provided vegetative mapping information for the West
Creek watershed, is a forester, graduated from Auburn University, with
five years forestry experience in Southeastern Alaska. This experience
includes growth and yield work for the U.S. Forest Service, forest inven-
tory studies for Sealaska Timber Corporation, and forest-habitat invest-
igations for the Alaska Department of Fish and Game.
Archaeological-historical work was carried out by Tim Moore under the
direction of Professors Lyle Hubbard and Wallace Olson of the University
of Alaska, Juneau.
Tim Moore is an archaeological graduate from California State University.
His experience includes archaeological digs in California as well as environ-
mentally related archaeological investigations. Tim is a four year resident
of Southeast Alaska.
Lyle Hubbard, who anticipates receiving his PhD in physical anthropology
in June, 1982, brings 15 years of varied Alaskan experience. He has partic-
ipated in archaeological projects in both the Pacific Northwest and Southeast
Alaska. Lyle's varied biologic training and experience provides an addition-
al basis on which to evaluate this archaeological setting.
Wal Olson is a leading Alaskan authority on the ethnology of native
Alaskans, particularly the Tlingit culture. In this role he provided
AUTHORSHIP and ACKNOWLEDGEMENTS continued:
guidance and information dealing with the native settlement at or near
Dyea.
Fisheries work was conducted under the joint guidance of Alexander Milner
and Dan Bishop. Consultation and field data were received from Steve
Elliot and Mark Schwann of the Alaska Department of Fish and Game, Sport-
fish Division, Juneau; Joe Wallmo and Dave Clabough of Skagway provided
valuable field assistance.
Alex Milner, M.Sc. University of London, conducted dissertational studies
of streams in Glacier Bay National Monument to determine patterns of colon-
ization and succession in streams following glacial recession. He antici-
pates receiving his doctorate in hydro-biology in Spring, 1982 from the
University of London.
Dan Bishop, Project Leader and Coordinator of West Creek investigations,
has extensive experience with the bio-hydrology of coastal Alaskan streams.
Dan worked 11 years as a research scientist and a hydrologist for the U.S.
Forest Service in Southeast Alaska before beginning land-water resource
consultant work in 1973. He has extensive experience dealing with salmon
habitat, salmon hatchery siting, water quality control and land planning
efforts.
WILDLIFE SURVEY
PURPOSE
METHODOLGY
HABITAT TYPES
Conifer Forest
Riparian Shrub
Sedge Marsh
Upland Shrub •
Tundra .
Barren Rock
Glaciers
WILDLIFE SPECIES
Mountain Goat
Moose
TABLE OF CONTENTS
Sitka Black-tailed Deer
Black Bear
Brown Bear
Wolverine .
Wolf
Coyote •
Other Furbearers
Small Mammals
Waterfowl •
Grouse .
Eagles .
General Avifauna
USE OF WILDLIFE RESOURCES
POTENTIAL IMPACTS ON WILDLIFE
Mountain Goat
Moose and Deer
Black Bear
Brown Bear
Coyote •
Wolverine .
Waterfowl
Grouse •
Eagles •
General Avifauna
MITIGATION POTENTIAL .
REFERENCES
ARCHAEOLOGICAL-HISTORICAL RESOURCES SURVEY
PURPOSE
BACKGROUND INFORMATION
The Historical Setting
Geology
Flora
. .
1
1
3
4
8
9
9
9
9
9
10
10
10
11
11
12
12
13
13
13
13
14
14
14
14
19
19
19
20
20
21
21
21
21
22
22
22
22
24
25
25
25
27
28
METHODOLOGY .
ARCHAEOLOGICAL AND HISTORICAL RESOURCES
Proposed Dam and Reservoir Site
Power Corridor
Powerhouse Site •
Transmission Line Corridor
Powerhouse Site to Taiya River
Taiya River to Long Bay
Long Bay to Skagway .
Alternate Transmission Line Corridors .
POTENTIAL FOR IMPACT AND MITIGATION RECOMMENDATIONS
West Creek Drainage
Taiya River Valley •
East Ridge to Skagway •
Alternate Corridors
REFERENCES
FISHERIES INVESTIGATION
PURPOSE
Scope of Report .
METHODOLOGY .
RESULTS OF FISHERIES INVESTIGATION
West Creek and Tributaries
Above Upper Gorge
West Creek and Tributaries in
Middle Basin
Lower Gorge of West Creek
West Creek Between Lower Gorge
and Taiya River Confluence
Shorelines of Lower West Creek
and Taiya River
Eulachon Spawning Habitat,
Lower West Creek Vicinity .
POTENTIAL IMPACTS ON FISHERIES
PROTECTION, MITIGATION AND ENHANCEMENT .
APPENDIX A-I
B-1
B-2
B-3
C-l
SELECTED PHOTOGRAPHS OF WILDLIFE SURVEY AREA
CUL TURAL SURVEY INTERVIEW DATA
MARINE SHELL DEPOSIT
SINGLE STEEL WIRE LINE
MEMORANDUM FROM S. ELLIOTT RE. DOLLY VARDEN
POPULATIONS IN WEST CREEK
29
34
34
36
37
43
43
52
59
61
62
63
63
65
65
66
67
67
68
70
70
71
71
73
73
73
76
77
Figure 1.
Figure 2.
Figure 3.
Figure 4.
Figure 5.
Figure 6.
Figure 7.
Figure 8.
Figure 9.
Figure 10.
Figure 11.
Figure 12.
Figure 13.
Figure 14.
Figure 15.
Figure 16.
Figure 17.
Figure 18.
Figure 19.
LIST OF FIGURES
Generalized habitat types within the West Creek
watershed derived from Figure 2. The approximate
area of the proposed reservoir is outlined with dots
Vegetation type map for West Creek drainage.
The riparian zone at West Creek from the dam site
(right) to the head of the main stream. Small dots
north of stream channel represent shallow ponds in
marsh habitat. Cross-hatching represents the
approximate area of the proposed reservoir.
North end of Lynn Canal
Proposed West Creek hydroelectric project
development area
Cultural resources survey area .
Taiya River Valley
7A -Powerhouse to Main Road
7B&C -Main Road to the Taiya River
Looking south at powerhouse site
South from powerhouse area showing
transmission line corridor
Junction of transmission line corridor
and main road
Looking north toward the house
shown in Figure 10
Mathews' cabin
West Creek road looking northeast,
Dyea lies to left
Gold rush era building SIO
West Creek road from Taiya River Bridge
towards Dyea Junction
Chilkoot Trail
Tree alignment at #13
Building remains at #15
Cabin, McDermott's.
5
6
15
31
35
38
39
40, 41
42
42
45
45
46
47
47
48
49
50
50
51
Figure 20.
Figure 21.
Figure 22.
Figure 23.
Figure 24.
Figure 25.
Figure 26.
Figure 27.
Figure 28.
Figure 29.
Figure 30.
Figure 31.
Figure 32.
Figure 33.
Figure 34.
Figure 35.
Looking southeast across cleared
land at McDermott's
Taiya River Bridge. Chilkoot Trail
trailhead on right
View south from Taiya River Bridge
View north toward Taiya River Bridge from 8.3 mile.
"Army building"
Marine shell deposit •
Marine shell deposit .
Green glass insulator on line from
Long Bay to Skagway
Skyline trail -Skagway area
Cabin at Skyline Trail trailhead •
Location of tributaries examined for
fishery habitat
Rapids below dam site
Cataract areas below dam site .
Cataract areas below dam site .
Series of falls and rapids in West Creek
lower gorge directly upstream from Taiya
River valley
Tributary which enters West Creek below bridge
51
53
53
54
55
56
56
58
60
61
69
72
72
72
74
74
LIST OF TABLES
Table 1. List of bird species expected to migrate through, breed
in or reside entirely in the West Creek drainage survey
area
Table 2. Location and description of historical and contemporary
site, between West Creek and Skagway
16
32
WILDLIFE SURVEY
FOR WEST CREEK HYDROELECTRIC PROJECT
PURPOSE
Assessment of wildlife resources and habitats in the West Creek drainage
system was conducted to identify potential impacts to wildlife resulting
from the West Creek Hydroelectric Project development and to recommend
mitigation. Specific objectives of the field program included:
1) Establish present patterns and potentials of wildlife uses in
the West Creek watershed, with primary emphasis on goat, moose,
and bear populations in the area of the proposed reservoir.
2) Describe and map the associated flora and relevant terrain
features which define wildlife habitat and influence use patterns.
3) Consider and evaluate possible impacts on wildlife of the pro-
posed hydroelectric development options.
4) Recommend appropriate mitigation measures.
METHODOLOGY
The survey of wildlife resources and habitats conducted in the West Creek
drainage system between 23 July and 27 August 1981, included (a) on-the-
ground examination of much of the vegetated portion of the impoundment
area and watershed above and below the proposed development site to
define the major habitat types present, (b) helicopter reconnaisance,
telescopic examination of the landscape, and the use of aerial photographs
to extrapolate the recognized habitat types to areas not examined on the
ground, (c) observation of animals and sign to estimate their distribution
and relative abundance within the watershed, and Cd) interviews of indi-
-1-
viduals for additional knowledge of wildlife in the West Creek area.
Wildlife surveys and vegetation assessments were conducted by Dr. O.
Charles Wallmo and Mr. Steve Jacoby, respectively.
By foot travel, thorough coverage was obtained of:
1) Most of the area within the watershed east of the longitude of
the dam site,
2) Most of the valley bottom from the dam site to the origin of the
main stream of West Creek,
3) Lower slopes of the northeasterly side of the valley from the
dam site through Sec. 1, T27S, R59E,
4) The elevation range of 2500-4500 feet in Sees. 5, 6, 8, and 9 of
T27S, R59E,
5) The elevation range of 3000-4000 feet in Sees. 19, 20, 29, 30,
and 31 of T27S, R59E and Sec. 31 of T28S, R59E, and
6) Sees. 28, 33, and 34 of T26S, R59E.
Mountainsides on the southwesterly side of the valley, including the west
side of the major, glacial tributary creek (i.e., Sees. 13, 24, 25, and 26
of T27S, R59E), were not covered afoot but were subjected to intensive
binocular and telescope surveillance on several days. All of the watershed
area, except 3-4 mi2 of ice cap on the northwest end, was reconnoitered by
helicopter, landing at numerous locations in the alpine and in forest
openings to define surrounding vegetation types and look for wildlife sign.
Individuals contacted for wildlife information included:
Lynn Bennett -L.A.B. Flying Service, Juneau.
Experience: aerial game counting for Alaska Department of Fish
and Game.
Dave Clabaugh -Ranger, Klondike Gold Rush National Historic Park.
General experience along Taiya River.
Lucinda Hites Clabaugh -Dyea resident.
Casual hiker lower West Creek, conservation activist.
-2-
Don Corwin -Skagway carpenter, outdoorsman.
Report of grizzly bear upper West Creek.
Bruce Edmonton -Ranger, Klondike Gold Rush National Historic Park.
General experience along Taiya River.
Skip Elliott -Skagway city manager.
Extensive hiking and camping in West Creek.
Steve Hites -White Pass R.R. employee; area historian.
Ray Hosford -resident of lower West Creek.
Rocky Lane -area resident, West Creek hunter.
Jack Lentfer -Supervisor, Game Division, Southeast Region, Alaska
Department of Fish and Game, Juneau.
John Matthews -Alaska Department of Fish and Game, Southeast Region,
inter-agency liaison officer, Juneau.
Roy Nelson -area resident, trail crew leader for Klondike Park,
West Creek hunter.
Doug Sandvig -Skagway carpenter, outdoorsman, professional wildlife
biologist.
Marvin Taylor -Skagway Councilman, courtesy introduction only.
Gerald Watson -Supervisor of Chilkoot Trail maintenance for Klondike
Park.
Dave Zimmerman -area game biologist, Alaska Department of Fish and
Game, Juneau.
HABITAT TYPES
For simplicity and uniformity, major vegetation types were considered as
general wildlife habitat types. A generalized distribution of major vegeta-
tion types is presented; detailed analysis of understory plant associations
was considered to be beyond the scope of this project. For purposes of
discussing wildlife distribution, the vegetation/habitat types identified
within the West Creek drainage are referred to as follows:
-3-
Conifer forest
Riparian shrub
Sedge marsh
Upland shrub
Tundra
Barren rock
Glaciers
For mapping of wildlife habitat types, the distribution was simplified by
combining all conifer types and bottomland types (Figure 1). Vegetation
classifications are differentiated, however, on Figure 2.
Conifer Forest
The Sitka spruce (Picea sitchensis) -Western hemlock (Tsuga heterophylla)
forest type is found generally throughout the West Creek system, representing
the only vegetative type of any significant commercial value within the
confines of the study area. Within the upper three miles of West Creek,
conifer forest is found on the steep slopes rising from the basin floor,
typically extending in bands and patches up to 2000 feet on slopes ranging
from 60 per cent to nearly vertical.
Within the lower four miles of West Creek, the spruce-hemlock forest is the
major vegetative cover on the basin floor and extends throughout all eleva-
tion zones up to 2000 feet. Old growth (+150 yrs.) as well as even-aged
young growth exist within the stand. Continual disturbances, due to the
steep terrain allowing for wind and avalanche activity, promote new stand
development.
Logging in the mid-1960's removed approximately 180 acres of spruce and hem-
lock timber growing on the north side of West Creek, approximately one and
one-quarter miles westward along West Creek from Dyea. Due to the surface
disturbance by the "cat logging" that was done within the cutting unit,
alder is competing heavily with the spruce and hemlock regeneration at this
time.
-4-
WOODLAND, SHRUB,
& MARSH
UPlAND SHRUB
ONE
\
"
MILE
Figure 1.
CONIFER FOREST TUNDRA &/or ROCK
GLACIER
, , ....... _/,
Generalized habitat types within the
l-lest Creek watershed derived from
Figure 2. The approximate area of the
proposed reservoir is outlined with dots
at elevations about 712 feet.
-5-
o
--".,.
/' -
/
",' -, I
./ "
,.
/--""
f~i,.~~~~~~~~~_PROPOSED . t"""O";;~;~\1~<AM ""
'~; \
\
\
\
\
)
/
/
Figure 2. Vegetation type map for the West Creek
drainage.
-6-
seA l E
o In lri~
~~~~~iiiiiiiiiiiiiiiiiiiiiiiiii3
legend
ALDER
l .... ~ : ........................... "'-'~ ",-,-=...:..;..Jl WILL OW
( -_. -SEDGE MARSH
\'\~:-'-.. ,----.. :.. ~ ...... ,. . ' -. -" .....
-'''"-,,... , ...
-. --.
SPRUCE / HEMLOCK
~ SPRUCE
COllONWOOD
Associate tree species within the spruce-hemlock forest include mountain
hemlock (Tsuga mertensiana), Western paper birch (Betula papyrifera) and
black cottonwood (Populus trichocarpa). Mountain hemlock is sparsely
distributed below 1200 feet, but combines with Sitka spruce to make up
the overall forest canopy in higher elevation zones. Paper birch occurs
on the Taiya River floodplain and on the low, drier east and west-facing
slopes of the drainage. Black cottonwood is typically mixed with Sitka
spruce along the glacial outwash areas and branch channels of West Creek
proper, constituting a riparian woodland habitat.
Distinct from the typical spruce-hemlock association, an approximately 55
acre stand of eighty year old Sitka spruce occurs within the impoundment
area at the confluence of West Creek and a large glacial tributary. The
dense stand is confined to a poorly-drained elevated bench, slightly above
the local elevation of West Creek. Due to the poor drainage character-
istics, the site productivity is relatively poor and the timber is small.
Common understory plants associated with the spruce-hemlock and spruce
forests throughout the West Creek area include:
Devil's club (Oplopanax horridus)
Stink currant (Ribes bracteosum)
Thimbleberry (Rubus parviflorus)
Salmonberry (Rubus spectabilis)
Blueberry (Vaccinium spp.)
High-bush cranberry (Viburnum edule)
Red-berry elder (Sambucus racemosa var. arborescens)
Located on the southeast-facing slope above the Taiya River is a relatively
small band of lodgepole pine (Pinus contorta). Pine is generally found
between 800-1300 feet elevation, but can occur in most elevation ranges in
the Skagway area. Associated species include birch, mountain hemlock,
spruce, alder and occasional cottonwood. Soils are considerably drier and
granitic outcroppings are common.
-7-
Riparian Shrub
Dense stands of alder, alder and willow, and willow (grading in this
order from better-drained to wettest sites) occur along West Creek and in
the floodplain.
The alder vegetation type, including Sitka and red alder (Alnus sinuata and
A. rubra), comprises a significant component of the vegetative cover within
the upper third of the West Creek drainage. This includes the area ranging
from the glacier terminus at the head of the West Creek eastward along the
creek floodplain for approximately three miles, where the conifer forest
begins to dominate.
The alder within this described route of glacial retreat occurs in thickets,
creating a very dense overstory shrub canopy. Willow (Salix spp.) is a
common associate shrub species in wetter soils, and black cottonwood and
Sitka spruce are commonly found where soils are more mature.
Beneath the alder canopy there is often a well-developed fern and grass
layer, as well as an association of herb and shrub species. The most common
woody plants associated with this vegetation type include:
Devil's club
Rusty menziesia (Menziesia ferruginea)
Stink currant
Thimbleberry
Salmonberry
Willow
Red-berry elder
Sweet gale (Myrica gale)
High-bush cranberry
Willow shrub thickets occur within the more poorly drained areas found on
the north side of West Creek beginning approximately one and one-half miles
down stream from the glacier and extending in patches about two miles east-
ward. Due to the nature of the occurrence of willow in relation to patterns
of drainage, willows converge with the alder type in better-drained soils
and with the sedge marsh type in the wettest areas.
-8-
Sedge Marsh
Sedge marsh vegetation occurs in proximity to riparian shrub sites where
drainage is poorest. Although the vegetation is somewhat variable, the most
common association includes sedges, rushes and grasses. Thick mats of
sphagnum mosses also occur.
Upland Shrub
Alder and/or willow occur on slide slopes and mountainsides up to 2500 feet
elevation generally, and to 3000 feet in some tributary drainages. Above
2000 feet willow is predominant, and in some areas, mostly at higher eleva-
tions, blueberry predominates.
Tundra
The transition from forest or upland shrub to alpine tundra occurs generally
between 2500 and 3000 feet. In this ecotone, stunted mountain hemlock,
subalpine fir and, occasionally, Sitka spruce occur in small clumps inter-
spersed in dwarf shrub/herb communities. Above 3000 feet dwarf shrub/herb
communities (e.g., Vaccinium, Salix, Lupinus, Ant ennaria, Ranuncu1us,
Potenti11a, Heuchera, Geum, Si1ene, etc.) give way to predominantly heather
communities (Cassiope, Phy110doce, Empetrum, Cerastium, etc.). Alpine
tundra is discontinuous above 4000 feet and essentially absent above 4500
feet.
Barren Rock
Most of the terrain above 4500 feet and slide areas below the glaciers are
largely barren of vegetation. Extensive sandy-gravelly areas of decomposed
granite occur on both sides of the valley above 3000 feet. The barrenness
of this zone is due primarily to disturbance (slides and soil instability)
and/or the long period of snow cover. Drift-snow fields and avalanche run-
out snow fields are common.
Glaciers
There are about 12-13 mi 2 of glacier within the West Creek watershed. At
higher elevations it is difficult to distinguish glacier and current snow
fields.
-9-
WILDLIFE SPECIES
Mountain Goat (Oreamnos americanus)
Mountain goat sign was encountered in all of the terrain covered above
timber line on both sides of the valley. On the basis of density of sign
(tracks and feces) the most heavily used areas appear to be Sees. 5 and 6,
T27S, R59E, in the range of 2500-4000 feet elevation on the southwest-
facing, northeast side of West Creek and in Sees. 13, 24, and 25, T27S, R58E
in the range of 2500-3500 feet on the south-and east-facing, west side of
"Glacier Creek" (the larger glacial tributary entering West Creek in Sec.
13, T27S, R59E). In the latter general area, 7 nannies, 6 kids, and one
yearling were observed on 7 August and 3 nannies, 3 kids, and one unidenti-
fied adult on 8 August. Adult males were observed in Sec. 36, T27S, R58E
and Sec. 27, T26S, R58E. An area resident (Skip Elliott) reported having
seen "lots of goats" in Sees. 35 and 36, T26S, R58E.
In our survey, goat tracks and fecal droppings were most abundant in a steep
area of sandy-gravelly decomposed granite in the range of 3000-4000 feet
elevation on the east side of Sec. 6, T27S, R59E. In the valley bottom
below this area, on the northeast side of West Creek, goat hair was found in
a willow thicket. During winter and early spring, goats in this region
commonly descend to steep, cliffy forested areas to forage and occasionally
descend to the valley bottoms. Valley bottoms cannot be considered essen-
tial habitat, however, though forested mountainsides often are.
A small number of area residents hunt mountain goats in the West Creek
drainage. Two (Tim Hendrickson and Roy Nelson) report bagging a goat in
1973 in Sec. 8, T27S, R59E. Two others (Rocky Lane and Thor Hendrickson)
have hunted in the Mt. Yeatman area within the West Creek watershed and the
Face Mountain area south of West Creek.
Moose (Alces alces)
Our observations, confirmed by the experience of local residents, indicate
that there are no moose in West Creek. However, the valley bottom, from the
-10-
proposed dam site upstream to the head of West Creek proper, contain perhaps
2 mi2 of marginally suitable moose habitat.
Sitka Black-tailed Deer (Odocoileus hemionus sitkensis)
West Creek is about 60 miles north of the northern limit of distribution of
Sitka black-tailed deer as defined by Alaska Department of Fish and Game.
There still are occasional reports, however, of black-tails in the Skagway-
Dyea area. In August 1981, one was seen (by Roy Nelson) at the Dyea (Taiya
River) bridge south of West Creek and deer tracks "headed north" were
reported to have been seen two days later (by Tim Hendrickson and Roy Nelson)
at Finnegan's Point and Canyon City north of West Creek.
Periodically excessively deep snow limits the northward extension of deer
range in southeast Alaska. There is no deer population in West Creek
currently and any deer that might colonize there would not persist long.
Black Bear (Ursus americanus)
Sign of black bears, consisting of fecal deposits, tracks, recently-used
trails, and evidence of foraging on vegetation was encountered generally in
all forested areas and throughout the riparian shrub and marsh zones from
the mouth of West Creek to the terminus of the glaciers at the valley head.
2 The occurrence of fresh sign over an area of about 5 mi and a linear
distance of 6 miles indicates that several black bears inhabit the West
Creek drainage.
An area resident (Skip Elliott) considers the vicinity of the upper end of
the clearcut and the proposed dam site to be most heavily used. This con-
forms with our observations in that general area on both the north and south
sides of the creek. We found equivalent densities of sign, however, in the
vicinity of the cabin midway up the creek and below the terminus of the
smaller valley glacier.
The local resident mentioned above reported having seen bears in the vicinity
of the cabin and the upper end of the clearcut. Other residents reported
-11-
bears seen in the clearcut and in the vicinity of the proposed powerhouse
site.
One area resident (Rocky Lane) reported killing a male in the fall of 1980
in Sec. 11, RS8E, T27S. Another resident (Thor Hendrickson) was reported to
have killed a black bear "near Mt. Yeatman" in fall of 1980.
We saw no bears during the wildlife survey. Tracks of a sow and cub were
found near the terminus of the smaller valley glacier. Contents of all
scats seen throughout the drainage area indicate that succulent vegetation
and berries were predominant foods of black bears at this season.
Brown (grizzly) Bear (Ursus arctos)
Fresh tracks of a large brown bear were seen on S August at 3200 feet eleva-
tion just north of the center of Sec. 8, T27S, RS9E, in the alpine tundra
type. A scat of brown bear, also in the alpine tundra type, was found at
about 3500 feet elevation in the northwest quarter of Sec. 29, T27S, RS9E.
Contents of the scat were principally crowberry leaves and fruit.
An area resident (Don Corwin) reported that an acquaintance (Sherell Stead)
saw a brown bear in 1979 near the terminus of the larger valley glacier at
the head of West Creek (ca in Sec. 35, T26S, R58E).Another area resident
(Roy Nelson) reports having seen brown bear tracks leaving West Creek near
the Taiya Slough every fall for the past 12 years. Joe Wallmo, a party to
this investigation, saw brown bear tracks in 1978 on the north side of West
Creek in the S.W. quarter of Sec. 7, T27S, R59E. Another area resident
(Skip Elliott) observed and measured tracks in upper West Creek that fit the
size of brown bear.
The sign seen by us indicates that at least one or two brown bears currently
include portions of West Creek within their home range.
Wolverine (Culo gulo)
An area resident (Skip Elliott) reported having seen three wolverines in
winter in the upper end of the valley.
-12-
Wolf ''';;;'';:=;;:''' lupus)
No evidence of wolves was found by us, nor did we obtain any reports of
wolves or wolf sign from others.
Coyote (Canis latrans)
We found feces of coyote in the clearcut and in the alpine tundra at about
4000 feet elevation in Sec. 30, T27S, R59E. A coyote was seen on 1 August
by Steve Jacoby, a party to this investigation, in the lower portion of the
clearcut. National Park Service personnel report seeing coyotes occasion-
ally along the Taiya River above and below West Creek. They are reported
(by Skip Elliott) to be less abundant now than in the winter of 1979-1980
following a high population of snowshoe hares. R. S. Fleming observed a
coyote 4 October, 1981, in Taiya valley at edge of trees at south end of
valley.
Other Furbearers
Feces of river otter (Lutra canadensis) were observed in the valley bottom
about halfway between the dam site and the head of the river. Marten
(Martes americana) have been reported near the cabin. Neither observations
nor sign of least weasels (Mus tela rixosa) and mink (Mustela vison) were
obtained, but it can be assumed that they occur in West Creek. No evidence
was found of beaver (Castor canadensis) within the West Creek watershed.
Small Mannnals
Sign and/or observations of deer mice (Peromyscus sp.), least shrews
(Microsorex sp.), porcupines (Erethizon sp.), and red squirrels (Sciurus
hudsonicus) indicate that they are widely and abundantly distributed
throughout the forested areas. No evidence of lagomorphs was found within
the West Creek valley, but varying hares (snowshoe rabbits) and sign were
seen in the Taiya valley bottom below West Creek. Evidence of voles
(Miyrotus and/or Clethrionomys) was noted in bottomland shrub and marsh
habitats.
-13-
Waterfowl
No ducks, geese, or swans were observed in the West Creek drainage. Open
water suitable for use by waterfowl is restricted to about 20 small ponds
with a combined area of less than 5 acres in scattered, small areas of sedge
marsh or willow/sedge marsh (Figure 3). For the most part, the unforested
areas of the valley bottom is dominated by dense alder, alder/willow or
willow thickets of low value for waterfowl. West Creek itself generally
flows too swiftly for use by waterfowl. R. S. Fleming observed widgeon
take flight from small pool in area above dam site, 3 October, 1981.
Grouse
Sightings and sign of blue grouse (Dendragapus obscurus) indicate that they
are generally distributed throughout the forested portions of the West Creek
valley and are more common in upland forests and along tree line than in the
valley bottom. Ptarmigan (Lagopus spp.) sign was found in varying density
in all portions of the alpine and alpine/forest ecotone that were covered
afoot. Rock ptarmigan (1. mutus) were observed in Secs. 8 and 30, T27S,
R59E, and a nest and a hen with 4 young were seen in the latter locality.
Eagles
Neither bald (Ha1iaeetus 1eucocepha1us) nor golden (Aguila chrysaetos)
eagles were seen within the West Creek valley. Several searches were made
to locate an eagle nest reported (by Skip Elliott) to be a short distance
south of the proposed dam site. It was not found. Bald eagles are common,
of course, along the Taiya River and Inlet but nesting is uncommon as far
inland as the area to be affected by the project.
General Avifauna
The kinds of birds to be expected within an area as large and diverse as
West Creek are too numerous to verify as to their presence, abundance, or
absence from a survey such as this. To cover the possibilities of species
whose populations might or might not be influenced by the proposed project,
Table 1 lists species that could be expected to migrate through, breed in,
or reside entirely within the area based on their occurrence in similar
-14-
I
f-'
V1
I
" "
.. ~ ..
... ..
"E'E'RvUIQ.. ELl:'V.
A.,-CA,.. ? /2. Po
" ... .. _ .. -.....
. --, .. ..
'" .. # ..... '" ..
'O(JU'
I
, .. :... ,*" - -..... , .. _.'" , ... .
"
-,
SC.Al.E.
21.10D· ...JOO 00' .. 00'/
• 1 • ,
Figure 3. The riparian zone at West Creek from the
dam site (right) to the head of the main
stream. Small dots north of stream
channel represent shallow ponds in marsh
habitat. Cross-hatching represents the
approximate area of the proposed reservoir.
--"\
habitats in the region. The list also indicates species recorded in the
Taiya valley in spring and sunnner of 1981 by Bruce Edmonton, U.S. National
Park Service, those observed by us in West Creek, and those whose popula-
tions might be significantly influenced, positively (+) or negatively (-)
by the project. The latter notation is basically speculative and would
require more study to be reliable.
Table 1 List of bird species expected to migrate through, breed in, or
reside entirely in the West Creek drainage survey area.
Observed in Potential
Taiya West Project
Valley Creek Influence
Whistling Swan x +
Canada goose +
Mallard x +
Pintail x +
Widgeon x +
Shoveler x +
Blue-winged Teal x +
Green-winged Teal x +
Cornmon Goldeneye x +
Bufflehead x +
Connnon Merganser x +
Goshawk
Sharp-shinned Hawk
Marsh Hawk x
Rough-legged Hawk
Red-tailed Hawk
Bald Eagle
Kestrel x
Blue Grouse x x
Spruce Grouse x
Rock Ptarmigan x x
Great Blue Heron +
-16-
Table 1 Continued.
Semipalmated Plover
Spotted Sandpiper
Greater Yellowlegs
Lesser Yellowlegs
Least Sandpiper
Common Snipe
Great Horned Owl
Short-eared Owl
Rufous Hummingbird
Gulls
Belted Kingfisher
Yellow-shafted Flicker
Yellow-bellied Sapsucker
Hairy Woodpecker
Downy Woodpecker
Northern Three-toed Woodpecker
Olive-sided Flycatcher
Say's Phoebe
Cliff Swallow
Violet-green Swallow
Tree Swallow
Steller's Jay
Gray Jay
American Magpie
Common Raven
Black-capped Chickadee
Chestnut-backed Chickadee
Dipper
Brown Creeper
Winter Wren
Robin
Varied Thrush
Observed in
Taiya
Valley
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
-17-
West
Creek
x
x
x
x
x
x
x
x
x
x
x
x
x
Potential
Project
Influence
+
+
+
+
+
+
+
+
+
Table 1 Continued.
Townsend's Solitaire
Hermit Thrush
Swainson's Thrush
Mountain Bluebird
Golden-crowned Kinglet
Ruby-crowned Kinglet
Water Pipit
Bohemian Waxwing
Orange-crowned Warbler
Yellow Warbler
Myrtle Warbler
Townsend's Warbler
Blackpoll Warbler
Wilson's Warbler
Northern Waterthrush
American Redstart
Western Tanager
Pine Grosbeak
Gray-crowned Rosy Finch
Redpoll
Pine Siskin
Crossbill
Savannah Sparrow
Slate-colored Junco
Oregon Junco
Tree Sparrow
Chipping Sparrow
White-crowned Sparrow
Golden-crowned Sparrow
Fox Sparrow
Lincoln's Sparrow
Song Sparrow
Snow Bunting
Observed in
Taiya
Valley
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
-18-
West
Creek
x
x
?
?
x
x
x
x
x
x
x
x
x
x
x
Potential
Project
Influence
USE OF WILDLIFE RESOURCES
Though West Creek is one of the more accessible drainages to the Skagway-
Dyea population, by virtue of the road entering the valley on the north side
and a trail to Lost Lake fringing the lower watershed boundary on the south,
it apparently is little used for hunting or wildlife observation. In
general, the valley walls are too steep and the valley bottom vegetation too
dense for the valley to be an inviting recreational area. One resident, to
our knowledge, commonly hikes into the upper valley. Except for his camp-
site, the only sign of hikers, hunters, or campers encountered beyond the
upper end of the clearcut or on the Lost Lake trail was of horse tracks,
noted on 10 September, upstream from the dam site on the unimproved trail on
the north side of West Creek. The identity and destination of the riders
are unknown.
Reports were obtained of 4 individuals who have hunted in the West Creek
drainage. Upper reaches of the logging road were littered with shotgun
shell casings and beverage cans used as targets. It was reported that some
individuals formerly drove into the clearcut in hope of shooting black
bears. The same area probably is hunted for blue grouse. The clearcut also
was reported to be a favorite area for berry picking. Only one resident
expressed concern over the potential of the project to adversely affect
wilderness or aesthetic values. Difficulty of travel is the primary reason
for low use of the area for hunting and wildlife observation. Additional
roads or improved trails could be expected to increase such use materially.
POTENTIAL IMPACTS ON WILDLIFE IN WEST CREEK DRAINAGE
Mountain Goats
Construction activities and their results (water storage and draw-down
in the reservoir, water diversion, and hydroelectric generation) as pro-
jected, would not, in themselves, have a direct influence of any measurable
magnitude on mountain goat habitat or population. However, this area is of
concern to Alaska Department of Fish and Game (personal communication with
Dave Zimmerman, area game biologist) because they believe that their reduc-
tion in goat hunting permits to the east may result in increased hunting
pressure in the West Creek vicinity. Any project-related activities that
influence hunter access to West Creek and surrounding goat habitat will be
-19-
of interest to ADF&G. The West Creek goat population can, however, sustain
a larger harvest than it apparently has experienced in recent years.
Moose and Deer
Moose and deer do not occur in West Creek and are of inconsequential future
concern. The valley itself would support too few moose to be of signifi-
cance as a huntable population either with or without the planned project.
While the reservoir, as planned, would usurp perhaps 1/4 of the present
potential moose habitat, it would significantly increase the extent of
desirable marsh and shallow-wa'ter habitat.
Should deer become established in West Creek as a consequence of invasion
over extended periods of years with mild winters, a population could not be
expected to persist regardless of future developments.
Black Bear
Activities associated with construction of the dam, power tunnel, and
powerhouse should be expected to influence the distribution of black bears
on both sides of the creek from the dam site downstream. On the south
side, activity might force bears to move southward to higher elevations,
westward into the large glacial tributary stream, or up the West Creek
valley. On the north side, bears might move northward out of the watershed
or up the West Creek valley.
These would be temporary movements followed by general readjustment of home
ranges after construction was completed. The eventual reservoir would
preempt about 400 acres of currently occupied bear habitat. The distribu-
tion of fresh sign suggests that several bears occupy virtually all of the
valley floor 'and forested slopes and that they have, therefore, fully
partitioned the habitat among the population. Individuals normally remain
within a definable home range, but home ranges commonly overlap. It can be
assumed that the distribution and overlap of these ranges are the result of
mutual adjustments by the bear to share the available resources without
excessively infringing upon each other. Loss of habitat to the reservoir
would necessarily require a readjustment of home ranges and, if the remain-
ing habitat were fully occupied, perhaps the eviction of one or more bears
from the watershed.
-20-
Optimum black bear habitat within the West Creek watershed probably en-
2 compasses about 10 mi The maximum surface area of the proposed reservoir
would be about 0.6-0.8 mi 2 . An area of less than 8 mi 2 studied by Lindzey
and Meslow (1977) had a population of 23 black bears with widely overlapping
home ranges. In West Creek, readjustment of home ranges would be a more
likely outcome than loss of bears from the resident population.
Brown Bear
One or two brown bears reside partially and/or temporarily within the West
Creek watershed. Its, or their, sign does not suggest that activities
associated with project construction would be disruptive. If the bears are
attracted to anadramous fish runs along the Taiya River, it is most likely
that routes alternative to those affected by the project would be selected.
Coyotes
Coyotes are so ecologically ubiquitous and adaptable that they should not be
influenced by the project. In any event, the area of the proposed reservoir
seems to be little used by coyotes.
Wolverine
This species has been observed only in upper West Creek and the project
should not be expected to affect them.
Waterfowl
Establishment of the storage reservoir in West Creek would result in the
loss of about half (less than 3 acres) of the miniscule amount of open
still-water habitat in the valley. In contrast, at a water surface level of
712 feet, the reservoir shore line would be approximately 5 miles in length.
Based on an estimated average gradient of 1%, this would add some 60 acres
of shoreline water less than 2 feet deep in addition to 300-400 acres of
deeper water. Draw-down and refill rates and timing would influence
habitat quality, but it is apparent that much more waterfowl habitat would
be created than destroyed.
-21-
Grouse
Of perhaps 8 mi2 of blue grouse habitat about 1/2 mi 2 of poorer quality
habitat would be inundated by the proposed reservoir. Assuming that the
small number of birds there would move elsewhere and cause some readjustment
among ranges in the peripheral population, any reduction in the overall
population probably would not be measurable.
Ptarmigan would not be affected by the project.
Eagles
Further effort should be applied to determining positively whether or not
active bald eagle nests exist where they may be influenced by hydroelectric
construction activities, installation, and operations. (See Mitigation
Potential.)
General Avifauna
The character of potential influences is indicated in Table 1. Of those
species that might be negatively inf1uenced~ none are rare or endangered.
Only a small fraction o~ the populations that may be observed during migra-
tions remains to breed in West Creek. Still, a certain amount of bottomland
habitat would be irretrievably 10st--perhaps 4/5 of the bottomland fore~t,
1/10 of the bottomland brush and woodland, and 1/4 of the marsh habitat.
This loss could be expected to result in a reduction of the populations of
some species, but not in the elimination of any.
That influence would be balanced, however, by the addition or creation of
habitat for other species, resulting in a more diverse avifauna overall.
MITIGATION POTENTIAL
This evaluation addresses the project alternative with a storage dam to meet
Haines-p1us-Skagway energy requirements. Within that alternative there is
little latitude for modifications that would significantly alter the effect
on wildlife habitat. A lower dam (95 versus 107 feet; maximum water surface
elevation 700 versus 712 feet) that would accommodate only Haines' require-
-22-
ments would reduce the reservoir area to a degree that would be inconsequen-
tial in terms of wildlife influences. There does not appear to be a feasible
alternative dam site.
We do not believe, however, that the project as proposed would have measur-
able detrimental effects on the populations of any species now present in
West Creek. It would create new habitat for several species of waterfowl
and other limnetic birds. Accordingly, the timing of drawdowns and pefil-
lings of the reservoir may become of concern to Alaska Department of Fish
and Game and u.s. Fish and Wildlife Service, depending upon species that
became established.
If the bald eagle nest reported near the dam site is verified as an active
nest, the U.S. Fish and Wildlife Service must be notified. and appropriate
action be taken to assure compliance with legal requirements for its
protection.
In the vicinity of the proposed dam site, there is a narrow valley-bottom
corridor that will be influenced by the access road on the north s1de of the
stream, possibly affecting the travel routes of wide-ranging mammals. By
keeping the final route of this road as close to the stream as possible
where the road leaves the clearcut and turns southerly toward the dam site,
that effect can be minimized. In addition, attention should be given to
keeping any ancillary structures out of that corridor area. Length, width,
and depth of the proposed reservoir should be expected to have a negligible.
if any, effect on the movement of wide-ranging mammals.
-23-
REFERENCES
Lindzey and Nes1ow, 1977. Home Range and Habitat Use by Black Bears in
Southwestern Washington, Journal of Wildlife Management, 41:413-425.
-24-
ARCHAEOLOGICAL-HISTORICAL RESOURCE SURVEY
FOR WEST CREEK HYDROELECTRIC PROJECT
PURPOSE
An archaeological-historical survey was conducted to locate and describe
culturally significant resources within the proposed area of development
for the West Creek Hydroelectric Project. Specific objectives for the
survey included:
1) Identify potential sites of cultural significance through
research of ethnographic literature, review of pertinent .
registers and interviews with local residents.
2) Describe and map cultural resources identified during a
reconnaissance of the study area.
3) Identify areas which merit special consideration during
project design, construction and operation, and suggest
mitigation measures.
4) Document areas of recent pertinent disturbance including
roads and residence activities.
BACKGROUND INFORMATION
The Historical Setting
There are two phases of cultural development in the Dyea!Skagway area which
are the source for most of the cultural resources documented during this
survey. These two deve19pment phases include the pre-contact use of the
area by the Chilkat Tlingits and the post-contact development boom which
accompanied the gold rush stampede in the late l8g0's.
-25-
The northern end of Lynn Canal was included in the territory of the Chilkat
Tlingits. The Chilkat name is used collectively to include Tlingits from
the Klukwan and Chilkoot (Haines) territories. The Chilkat territory,
including the drainages of the Chilkat, Klehini, Chilkoot, Taiya and Skagway
Rivers, was rich in resources and included major strategic trade routes to
interior Alaska (Goldschmidt and Haas, 1946:38). Prior to Tlingit occupancy
of the area, Athapaskans from the interior had followed these routes to the
coast and established settlements (Oberg, 1973:56).
The trading economy was important to the power and resource base of the
Chilkat. Trade items transported to the interior included eulachon oil,!/
cedar bark baskets, shell ornaments and other marine resources. Trade
material coming to the coast included copper, hides, fur, thongs and sinew
(Oberg, 1973:108).
The Taiya Inlet area (Taiya and Skagway Rivers) seems to lack the abundance
and diversity of resources and favorable weather of the more populated
Chilkat River drainage. Nevertheless, small Chilkat villages or seasonal
camps were established at Dyea (on the Taiya River) and Skagway (Goldschmidt
and Haas, 1946), and the Taiya River trade route via Chilkoot Pass was
actively used.
The pre-contact ethnographic literature focuses on Dyea, leaving the extent
of activity in Skagway somewhat in question. Dyea is reported by some as a
seasonal camp or village, although others indicate it had permanent status
(Goldschmidt and Haas, 1946:50; Sealaska Corporation, 1975:578). Although
Dyea may have had year-round residents, its role as a major Tlingit popula-
tion center is in question.
During the fur trading period the Chilkats retained control over interior
trade routes. However, by the late 1800's a growing interest in gold
strikes in interior Canada brought competition for the use of Chilkat routes
and new forms of development to traditional Chilkat village and camp sites.
l/Eulachon (Thaleichthys pacificus) is an oily smelt which spawns in many
mainland rivers of the northwest coast. See also section on fishery
evaluations.
-26-
A trading post was established at Dyea in 1884 to service the increasing
number of prospectors traveling to the gold fields along the Fortymile
River, and later to Circle City. Activity in Dyea and on the Chilkoot
Trail gained momentum, and greatly increased following the news of the
Klondike discovery in 1896 (Spude, 1980:23).
Dyea quickly developed into a major staging area for large numbers of stam-
peders. Buildings and tents sprang up in Dyea almost overnight and the
shallow tide flats south of town became the site for unloading mountains
of supplies.
The original Chilkoot Trail headed north along the west side of Taiya River
and the heavily used lower sections became a wagon road. Tents, cabins and
shelters were erected along the trail for several miles out of town
(Carley, 1981).
Deep water docking facilities in Dyea were initially lacking and freight
was loaded onto lighters which were grounded with the falling tide. Two
wharves were eventually constructed in Dyea. The first, Dyea Klondike
Transportation (DKT) Company wharf, was located southwest of town on the
west side of Taiya Inlet and was connected to Dyea by a wagon road and toll
bridge. The Dyea Wharf (or Long Wharf) extended directly into deep water,
but was completed after the main gold rush activity had subsided and was
little used (Spude, 1980).
Activity in Dyea and on the Chilkoot Trail declined by the end of 1898.
Many Dyea buildings fell into ruins, while others were moved to growing
communities in southeast Alaska or were dismantled for lumber. Several
homesteads in the area remained occupied and a small Tlingit population
resided in the area into the 1930's (Spude, 1980).
Geology
Taiya Inlet occupies a secondary fault zone branch from the primary Lynn
Canal-Chilkat Fault. The area is predominantly a plutonic intrusive for-
mation, chiefly quartz diorite and granodiorite, which formed during the
Jurrasic and Cretaceous periods (Yehle and Lemke, 1972).
-27-
Glacial activity throughout the area is evidenced by smooth, rounded bedrock
outcrops and topographic features such as lateral and terminal moraines.
Several large glaciers can be seen in the mountains surrounding the Inlet.
Land rebound, characteristic of areas of glacial retreat, is an ongoing
process in the area. At Skagway, a marine shell deposit now located at
9.6 m above mean sea level was dated by the Carbon 14 technique at 2,880:
250 years old (Yehle and Lemke, 1972).
Forest soils on slopes above the Taiya valley floor commonly have 15 to
30 cm of organic material over shallow, coarse-textured mineral soils
which may be derived from colluvial material, from glacial deposits (as
was the mouth of West Creek), or from weathering in place of the local
granitic bedrock materials. Soils in the Taiya River valley bottom are
built from alluvial materials which are predominantly silts, sands, and
gravels. A characteristic profile is a thin ( 15 cm) surface of organic
material overlying sand and silt of variable thickness intermixed with, or
overlying, layers or lenses of coarse gravel materials. Many locations
show soils disturbed by recent activities including land clearing, road
building, or logging. These disturbed areas usually have very thin sur-
face layers of organic material including moss and litter, overturned
stumps and debris (over roadways), and logging debris.
The general vegetation classification for the project area is coastal
spruce-hemlock forest. The forests in the dam, reservoir and power corridor
sites are dominated by Sitka spruce (Picea sitchensis) and Western hemlock
(Tsuga heterophylla). Common shrubs in forest openings and edges include
rusty menziesia (Menziesia ferruginea), blueberries (Vaccinium ~), and
currants (Ribes ~). Forest openings with wetter soils contain devil's
club (Oplopanax horridus), red alder (Alnus rubr~), Sitka alder (!. sinuata),
willows Salix ~), and other miscellaneous herbs and shrubs.
In the flood plans and valley floors of the area the most common trees and
shrubs are the black cottonwood (Populus trichocarpa), Sitka spruce, red
and Sitka alder, willow, high-bush cranberry (Viburnum edule) and a variety
of other herbs and shrubs.
-28-
Lodgepole pine (Pinus contorta) and western paper birch (Betula papyrifera)
are common on the dry rocky ridges between the Taiya River valley and
Skagway (Viereck and Little, 1972).
A more detailed vegetational survey of the West Creek drainage is described
in the Wildlife Survey report, also in this volume, and a vegetation map is
presented (Figure 2).
METHODOLOGY
Assessment of archaeological and historical resources was conducted in the
West Creek drainage on 20-28 August, 9-12 September, 29-30 October, and 6-7
November, 1981. This work included: (a) on-the-ground examination of much
of the proposed development site to locate cultural resources and contem-
porary activities in the project vicinity, (b) helicopter reconnaissance of
some difficult access areas, and (c) surveys of ethnographic literature and
registers and interviews with local residents (Appendix B-1) for additional
knowledge of cultural resources. Surveys were conducted by Mr. Tim Moore,
with technical assistance from Mssrs. Lyle Hubbard and Wally Olson, and
field assistance from Mr. Nathan Bishop.
Pre-field research was greatly assisted by information contributed by
Mr. Robert Loescher of Sealaska Corporation and the Klondike Gold Rush
National Historic Park staff. Local informants contacted for cultural-
historical information included:
Rick Burroughs -Long Bay area resident.
Dave Clabaugh -Ranger, Klondike Gold Rush National Historic Park.
Skip Elliott -Skagway city manager, Dyea area resident.
Fred Hosford -Skagway resident.
Alf Kalvick -Dyea area resident.
John and Lorna McDermott -Dyea area residents.
Bob Rapuzzi -Skagway resident.
Elizabeth Selmer -Skagway resident.
-29-
Areas of intended survey coverage were defined based on the layout of
proposed hydroelectric developments (Figure 4) and the degree of cultural
significance referenced by literature sources and local informants. Signi-
ficant cultural resources were defined as identifiable artifacts or features
which provide evidence of previous activity in the survey area. Areas of
known high sensitivity and moderate or high archaeological potential were
surveyed using transects to assure proper coverage. In the valley the
transects were kept as wide as vegetation would allow while maintaining
visual contact between two party members. On steep slopes, the transects
were wider and voice contact was maintained.
Survey areas were modified in-process due to inclement weather, inacces-
sible topography, heavy vegetation, as well as to facilitate coordination
of field efforts with those of other project teams.
Generally, coverage was obtained of:
1) The proposed dam and reservoir site (about 500 acres),
located approximately two miles upstream from the conflu-
ence of West Creek and Taiya River,
2) The east and west ends of the power corridor,
3) The powerhouse site,
4) Most of the transmission line route, which follows the
Skagway!Dyea road south along the east side of the Taiya
River to Long Bay, and then southeast to Skagway, and
5) An alternate transmission line route along the west side
of the Taiya River valley.
An additional alternate transmission route which directly traverses the
mountains to Haines was considered, but an on-the-ground survey was not
conducted in this area.
-30-
Figure 4. North end of
Lynn Canal.
Legend
® Town
_ Stream/River
Glacier
1" .. 2. 75 mi (4.4 kill)
o
~C.R I.. E..
PRoPOSEd
PRojf'c:t
AREA
-" (
-31-
I
I , t
I I , ~
" ~ _ ..
Table 2 Location and description of historical and contemporary sites
between West Creek and Skagway.
No. Name
Loca-
tion
1. Hosford's residence T.27S.,
R.59E.,
Sec. 15
2. Powerhouse site Sec. 15
3. Wagon Wheel Ranch Sec. 15
4. Sec. 15
5. Kalvick's residence T.27S.,
R.59E.,
Sec. 22
6. Mathews' cabin Sec. 22
7. Sec. 22
8. Triangle Sec. 22
9. "North Dyea"
10. Taiya River Bridge
11. Chilkoot Trail
crossing
12. Earth ramp & pit
13. Tree fence
14. Dugouts
15. Large clearing
16. McDermo.tt' s cabin
17. Slough
18. New Chilkoot
Trailhead
19. Army buildings
20. NFS Ranger Station
Sec. 22
Sec. 22
Sec. 22
Sec. 22
Sec. 22
Sec. 22
Sec. 22
Sec. 22
T.27S. ,
R.59E.,
Sec. 27
Sec. 27
Eleva-
tion Description
20' Residence & out-buildings
20' Two sheds & refuse
20' Log house & shed
Date
Contemporary
1950's
Unknown
Log house under construction Contemporary
New cement foundation
20' Residence and out-building
20' Log cabin
Surface artifacts & pits
20' Wagon parts
Late 1970's
1920's
Unknown
Unknown
20' Structures, pits & artifacts 1890's
30' Steel bridge
20' Trail crosses main road
20' Ramp partly across a slough
20' Spruce planted for fence
post and house site
Garden
20' 3 rectangular "cellars"
Lumber and debris
Two gardens
20' Log cabin
House under construction
20' Chilkoot Trail becomes vague
in Taiya River bottom/slough
15'
10' Army building from Skagway
10' Camp ground and trialhead
parking
-32-
1940's
Unknown
1890's
Contemporary
1890's
Unknown
Contemporary
1898
1940's
Contemporary
Table 2 (Continued)
Loca-E1eva-
No. Name tion tion Descri]2tion Date
21. Marine shell deposit Sec. 27 15' Small deposit of shells Unknown
22. Cabin Sec. 27 75' Residence at 8.0 mi. Contemporary
23. Trailer T.27S., 100' Residence at 7.2 mi. Contemporary
R.S9E.,
Sec. 34
24. Telephone/telegraph T.27S. , 75'-Single steel wire 1890's
line R.S9E., 200'
Sec. 34&35
25. Two cabins T. 28S. , 100' Residence at 6.3 mi. Contemporary
R.59E. ,
Sec. 3
26. Long Bay T. 27S. , 15' Log Cabin 1940's
R.S9E. ,
Sec. 35
Two houses Contemporary
27. Beach house Sec. 35 5' Residence Contemporary
Unknown
28. Skyline Trailhead T. 28S., 300' Shed and trailhead Unknown
R.59E.,
Sec. n
29. Cabin Sec. 11 250' Residence Contemporary
30. Bridge Sec. 11 20' Foot bridge footing Unknown
31. Pet cemetary Sec. n 30' Contemporary
-33-
Limitations in survey coverage are specified in the sections which. describe
survey results for each area. No testing or excavation was done during the
course of the survey, as required in the field archaeolo& permit. However,
cut banks and disturbed areas were examined for evidence of artifacts dis-
tributed beneath the surface. The areas observed provided a low yield of
artifacts, and no conclusive pattern of artifact distribution at depth was
noted.
Items of cultural significance noted during the survey are generally
described in the order in which they would be encountered moving from
northwest (dam and reservoir site) to southeast (Skagway terminus of the
transmission line) within the proposed development corridor. A numbering
system for points of interest mentioned in the text is shown in Table 2,
and is used on accompanying maps.
ARCHAEOLOGICAL AND HISTORICAL RESOURCES
Proposed Dam and Reservoir Site
Rugged glacial topography and poorly developed access routes made surveys
in the dam and reservoir site (Figure 5) difficult. Access to the north
side of West Creek was provided by a logging road which terminated in a
clearcut landing approximately 1,000 m below the dam site. Access to the
dam and reservoir was achieved by a trail which paralleled West Creek and
by cross-country (unimproved access) travel. Blazes and minor trail im-
provements appeared to be nearly the same age as the logging activity, and
probably provide hunting access.
The dam site and spillway area north of West Creek, and the location where
test core drilling will take place, were surveyed. No evidence of historic
trails or other cultural features were noted during visual reconnaissance
of these areas.
Cultural resources were not observed along the north side of West Creek or
at the reservoir site. No mining activity was noted between the reservoir
and the dam site.
-34-
Project and survey area
,~ .2M':
:>
-35-
Figure 5. Proposed West Creek
hydroelectric project
development area.
Access to the south side of West Creek was provided by helicopter. No
resources of archaeological-historical significance were noted at the
proposed dam and reservoir site. An aerial reconnaissance was made of the
proposed dam and reservoir sites, and of the West Creek drainage below the
development area.
Conversations with local residents provided two additional possibilities
for areas of cultural significance in the dam/reservoir area. Mr. Bob
Rapuzzi, a resident of Skagway, suggested a trail may have existed along
the south shore of West Creek and traversed the mountains to the Chilkat
River area (Klukwan). Although it is possible to traverse the route, the
rugged topography makes it an unlikely route for frequent travel. No
evidence of the trail was noted during a cross-country survey conducted
along the proposed route. However, vegetation could easily have oblit-
erated the historic trail.
Mr. Skip Elliott, a resident of Dyea, has collected information on the
historical activities of the greater Dyea area and has hiked extensively in
the West Creek drainage. Historical records Mr. Elliott obtained from
Skagway City Hall indicated the presence of mining claims in upper West
Creek valley. Mr. Elliott felt that most, if not all, of the claims were
outside the area to be developed. He has made several trips into the upper
valley looking for the claims, without success. It is not known if any of
the,claims were actually worked. With the vegetation cover in the area,
small claims with limited activity would be very difficult to locate.
During the reconnaisance of the reservoir area, this survey crew found no
indication of mining activity.
Power Corridor
Due to the lack of proposed surface disturbance along most of the power
corridor route and difficult access through dense forest cover, only the
corridor ends (west end at the dam site and east end at the powerhouse)
were surveyed. The approximate area of the proposed access road for the
power shaft above the power house was also exami.ned.
The western end of the corridor, located immediately upvalley from the dam,
was surveyed concurrent with the dam/reservoir survey. No cultural material
was observed in this area.
-36-
The eastern end of the corridor was surveyed concurrent with the power-
house site survey. This end of the corridor, including the power shaft and
access road(s), is in steep terrain covered with glacial moraine material.
At the time of the survey the proposed location for the access road was not
known. Therefore, a general reconnaissance was conducted on the hillside
south of the powerhouse site and at the power shaft location. The only
evidence of activity noted in the area was a steep unimproved trail to Lost
Lake (Figure 6) and recent survey stakes and flagging along the National
Historical Park boundary. No mention of the Lost Lake trail was found
during research, so it is not known how long the route has been used. No
other cultural material was noted in the area.
Powerhouse Site
The powerhouse site now proposed is located west of the valley floor, on
land which is administered by the National Park Service (#2). An alter-
nate site is located near the West Creek canyon in an area with large
morrain deposits and bedrock outcrops. The valley floor at the mouth of
the canyon is private property.
Several contemporary houses, numerous out-buildings, garden plots, and
assorted refuse were noted on either side of West Creek in the vicinity of
the alternate powerhouse site. Most, if not all, of the material scattered
around these residences appears to be within private property boundaries
(Figure 7A). The tail race from the proposed powerhouse will go through
this area near the base of the hill.
The proposed powerhouse site is situated 300 m south of West Creek at the
base of the hill (Figure 8). The valley floor in this area is coarse
aleuvial material mixed with some fines. Humus and moss covers the area
at a depth averaging 20 em or less. Unimproved roads meander through the
area along the base of the hill and east to the main road (Figures 8 & 9).
The roads appear to have been made by light grading or repeated driving.
Road widths vary from 8 m for a single track to 35 m at junctions and in
areas of logging activity.
-37-
Figure 6. Survey area.
Legend
• House
Road
- --Trail
-"-" Stream
o
~ xrs Ranger Station
lit == .5 mi (.8 kIn)
.!> l'1i I. 0 1'11.
I
N
-38-
I
1
'$\(,,(l..liUe. I
'T(:l,,''-I
I
I
I
I
I
78
7C
Fig.7 orientation
~
:ff:+
Figure 7A. Taiya River Valley
Legend A
Road
Chilkoot Trail
-"-J( Fence
IE Building ..L'1. & Garden
p Pits
.a Dispersed Logging
.t.. Photo Positioning
1" ?nn t (fiOm)
21)0 f'+ +'0" Fr
~======±I======~I
(,00", 120M
SCAL.E
N
7A
78
7C
Figure 7B. River
Valley
Legend
see 7A
ZOD ~+ 'leo +1-~t======~IC=======~1 o 60"", 1;1.0""'
S('AL..E:.
-L
fic..·11 . ,,, ..
II
II
II
II
II
II
II
II
II
f, II
tI Ol{ </& o :IF 15 If
yll
fi<..o'\'O II
\l
cllOp
~ 'l
#1+ II
" o II P"
1/
'/
II
II : <yv,'? # 13
.~ []
p /1
7A
7B
7C
7ig.7 orientation
o
p(,O
) fie.-1/ .A 11 1/
, . . . 1/
; ~'? .::tt:.l'3 / / :~ 0 II
• P Ii
1/
/I
1/
//
1/
1/
//
1/
1/
II
II
,,, 1/
I \ 1/ , ~
\ Fi"'i'.L 1. ....... ,/*12..
t:"\ 'I
"
1/
II
1/
II
II
1/
II
//
1/
1/
'/
"
;t11
-41-
/
/
/
/
/
" ;'
/
/
/
" N
Figure 7e. Taiya River
Valley
Legend
See 7A
I
/
/
200 f1" ¥OO~';
c=======~I======~! o ""'1'1'1 110M
seAL ..
The powerhouse location contains two small sheds with a large assortment
of contemporary debris; an approximate age of 30 years was confirmed by
Fred Hosford. The debris around the sheds includes appliances, stoves,
bed spring, building material, piling, steel pipe, and a two-hole out-
house. A long cleared strip goes up the hill from the sheds about 150 m.
A large tree at the uphill terminus and a wire on the ground indicate it
was a long wire antenna route.
Figure 8. Looking south at powerhouse site.
Figure 9. Southeast from powerhouse area showing
transmission line corridor.
-42-
The south side of West Creek upstream from the canyon mouth was surveyed
with several transects parallel to the creek where topography permitted.
The area was checked for indications of trails. Small game trails were
noted. No cultural material was observed.
The north side of West Creek was surveyed in a similar manner. Just west
of the log bridge which crosses West Creek, a road forks to the south into
an area known as Wagon Wheel Ranch (#3). There is a small well-maintained
log house, a log out-building,a large log home under construction, numerous
plots of flowers, and several large garden plots. In the flats toward the
canyon mouth there is an accumulation of aluminum irrigation pipe which had
apparently been part of a gravity flow system for garden water. There is
evidence of wood cutting activities in the area.
No items of archaeological or historical significance were noted at the
proposed powerhouse site.
Transmission Line Corridor
The proposed 9 km long transmission line corridor extends from the power-
house site southeast across the Taiya valley, along the east side of the
Taiya River into Long Bay, and then south to Skagway. The following de-
scription of the survey route is generally presented in a north to south
progression. However, the Chilkoot Trail survey is described from the
point where the trail crosses the Skagway-Dyea road northward to the Kinney
Bridge area (which is outside the transmission corridor to the north.)
Powerhouse Site To Taiya River
This section of the transmission line corridor (Figure 5) lies within the
Taiya valley and is included within the boundaries of the Klondike Gold
Rush National Historic Park. However, the corridor may cross private
inholdings within park boundaries.
Numerous cultural artifacts, which were generally related to the gold rush
era, were documented along this section of the line. Briefly, these
included the Chilkoot Trail route, debris and structures along the trail
-43-
and the remnants of the northern portion of the community of Dyea. The
presence of the native village of Dyea was not identified by this survey
team and its existence and former location is known only through literature
research. Evidence of the pre-gold rush native village was probably
overlain by, and incorporated into, site developments which followed.
The short section of transmission corridor between the powerhouse and the
Skagway-Dyea road contains numerous contemporary cultural resources. The
area is criss-crossed with roads and tracks which lead to house sites,
small abandoned sheds, barb wire fencing, and a new concrete house founda-
tion (#4). Associated material noted in this area included abandoned wood
stoves, large kitchen appliances, 55-gallon drums, batteries, motor vehicle
parts, building supplies, and food and beverage containers.
This area has been selectively tractor logged as evidenced by tracks,
stumps, and irregular piles of dirt, rock, and wood. Because of the rapid
growth of vegetation it is difficult to determine the full extent of the
area logged. However, scattered evidence of logging (primarily west of
the main road) extends south to near the Dyea junction (#8).
The transmission line corridor continues east to an intersection with the
main road and then follows it south (Figure 10, 11, and 7B). In the section
between the house foundation (#4) and the main road the soil changes from
the shallow rocky aleuvium in the west to a deeper deposit of silt and
sand. At the Kalvick residence (#5) the well point hit gravel at 5 m.
Gardens and other disturbed lands here and to the west are primarily soil
with very little surface gravel. The Kalvick's have built a house, several
out-buildings, and a fenced yard and garden plot.
The main road which runs from Skagway to West Creek was constructed during
the late 1940's. The road corridor was opened by pushing the vegetation
cover and top soil to either side. The all-weather road bed consists of
river gravel that was hauled in. The road bed averages 8 m in width with
-44-
a graded apron on either side. The width of the aprons along the roadside
varies greatly from 4 m to over 20 m. There is some disturbance beyond
the apron where the excess construction material was deposited.
Figure 10. Junction of transmission line
corridor at main road.
Figure 11. Looking north toward the house
shown in Figure 10.
-45-
The first historical material found near the transmission line corridor was
at the Mathews Cabin (#6, Figure 7C). The walls of the cabin are intact but
the roof has fallen in. According to Spude (1980), this was the residence
of Mr. William Mathews, a Tlingit and long-time resident who homesteaded
here in the 1920's (Figure 12). At this point the total width of the road's
right-of-way is quite narrow when compared with other sections along the
road. Some scattered artifacts and pits were noted around and behind the
cabin. The area of activity extends 40 m to the northwest to the edge of a
slough and southward along the slough to the Dyea Road (#7). It is diffi-
cult to determine origins of the ma"terial but most (particularly away from
the cabin) is probably from the gold rush era. Material noted included
enamel pots and pans, rusty cans, sheet metal and scraps of iron.
Figure 12. Mathews' Cabin.
-46-
The tri~ngle formed by the three roads has been disturbed by road building,
but does contain partial remains of a heavy wagon (wheel, axle, and heavy
metal straps) and assorted material typical of that scattered along the
trail (#8, Figure 13).
Figure 13. West Creek
road looking northwest.
Dyea lies to left.
South of the road gold rush era structures, pits, and artifacts occur more
frequently (#9). This area has been well documented in a previous investi-
gation by Carley (1981), and numbers indicated on Figure 7C are designations
assigned by Carley. The structure shown in Figure 14 is about 15 m south
of the road.
-47-
Figure 14. Gold rush
era building 510.
The main road corridor between the Dyea junction and Taiya River Bridge
(#10) is generally wide (up to 45 m), but narrows to 15 m near the Chi1koot
Trail crossing (#11) and the bridge (Figure 15). The soil in the area is
predominantly silt, but with lenses of gravel.
Figure 15. West Creek road from Taiya River Bridge
towards Dyea Junction.
The Chi1koot trail runs south-north between the modern road and the Taiya
River" (Figure 16). The trail crosses the Skagway-Dyea road 175 m northwest
of the Taiya River Bridge and continues north for 700 m before ending at
the edge of a large slough (#17). It should be noted that the historic
trail at this point was actually a wagon road which continued north of the
slough approximately 500 m before crossing the Taiya River on the Kinney
Bridge. Spude (1981) noted that the trail route can be easily distinguished
up to the Kinney Bridge by remains of building foundations and tin cans.
Following the Chi1koot Trail north from the road junction the first
feature noted is a contemporary earthen ramp partly spanning a slough (#12).
It appears that the material for the ramp came f-com a disturbed area across
the trail.
-48-
---4 _ We='ST" c..~e\,-
# -----*-. ~. ----. -:::::::;;..-~
o
Figure 16. Chilkoot Trail.
Legend •
)::( ...
1" 1100'
House
Road
Trail
Stream
Bridge
POB 1303 datum
(330 m)
SCRLE.
I
/
I
f
\
\
I
I
I
/
/
/
/
/
I
/
I
I
I
I
MoPeR/v
I Crl\L-I<.OOI
\
I TRA.\L-
I
I
I
I
I
A large clearing 150 m north of t~e road junction contains 2 rectangular
pits and 2 rows of spruce trees (#13, Figure 17). The trees were used as
"fence posts" and their size indicates this site is from the gold rush
era. Tree alignments in the downtown Dyea area were used for comparison.
A small contemporary fallow garden plot is located to the west.
Figure 17. Tree
alignment at #13.
There are three rectangular pits further to the north (#14), adjacent to
a clearing that contains remnants of wooden structures and recently culti-
vated garden plots (#15, Figure 18). The site appears to be from the gold
rush era, but it has been disturbed and altered by recent activities.
Recent artifacts were scattered about; however, some pieces of tin, stove
pipe, galvanized roofing, and metal rods are in a similar state of decay
as the gold rush material observed in the Dyea area.
Figure 18. Building
remains at 1115.
The next major feature up the trail is the log cabin at McDermott's farm
(#16) which dates from 1897-98 and is still occupied. The cabin shows
common log construction problems, including lack of foundation, sagging
2 .
and deterioration of some logs (Figure 19). A 175 m area around the
cabin has been recently cleared and fenced (Figure 20) to accommodate
several large garden areas and farm animals. The trail reaches the slough
150 m north of the cabin. A large pile of soil and trees has been pushed
to the north edge of the property near where the trail disappears at the
edge of the slough. The soil is predominantly fine river deposits, silt,
and sand.
-51-
Figure 19. 1898
Cabin, McDermott's.
Figure 20. Looking
southeast across
cleared land at
McDermott's.
Tin and light metal artifacts are scattered along the trail the entire dis-
tance from the Skagway-Dyea road to the slough. The composting vegetation
tends to mask the smaller materials such as heavier metal pieces, glass and
ceramic fragments, nails, and other construction materials. No attempt was
made to catalog all the artifacts scattered along either side of the trail,
nor was any digging done. This section of the trail was surveyed using
transects of 10 m spacing parallel to the trail. Dense vegetation pre-
vented complete coverage in several areas.
The survey area was extended south of the Skagway-Dyea road and out of the
defined transmission corridor in order to attempt to identify the native
village site of Dyea and to estimate its proximity to the proposed hydro-
electric development. A survey conducted for Sealaska Corporation (1975),
by Whilsey and Ham, Inc., Seattle, had designated a Point of Beginning
(POB) or main datum for native village site no. 1303 based on information
obtained from two informants, though no artifacts were located. The datum
is on the northern boundary of the site and is located 700 m south of the
Taiya River bridge.
Carley (1981) located two additional structures (designated as "Indian
Houses" on the 1918 Pullen Homestead map) which are 425 m north of site
1303 datum. The remains of these structures appear to be more recent than
the gold rush era. It is not known if the structures were located on
sites which pre-date contact with white men or if the natives had moved
northwards because of increased gold rush activities. Available infor-
mation indicates that, while the exact location of the native village site
is not known, it probably lies south of the proposed transmission line
corridor.
Taiya River to Long Bay (Nahku Bay)
This section of the transmission line corridor traverses the east side of
the Taiya River flood plain and crosses a steep rocky ridge of exposed
bedrock into Long Bay.
-52-
The trailhead for the Chi1koot Trail currently used by hikers is located at
the southeast end of the Taiya River Bridge (#18, Figure 21). The new
trailhead was placed on the south side of the bridge because there is no
longer any bridges across the Taiya River on the original trail.
Figure 21. Taiya
River Bridge. Chi1koot
Trail trailhead on
right.
The main road south of the bridge was constructed by the same manner
described in the previous section (Figures 22 & 23).
-53-
Figure 22. View south
from Taiya River Bridge.
Figure 23. View north toward Bridge
from 8.3 mile.
The survey was conducted by walking transects south from the Taiya River
Bridge. Both sides of the Skagway-Dyea road have been scarred and inundated
by flood waters from the river. Sloughs and swamps on either side of the
road dictated some modification of transect routes.
A group of wooden structures was noted in a clearing 50 m east of the main
road at mile 8.4. The two houses and several out-buildings, now in various
stages of disrepair (#19), were constructed in the late 1940's. The
southern-most house appears to be occupied at least periodically, but no
residents were seen during the survey (Figure 24). The northernmost
building, which is deteriorating, appears to have been constructed from
pre-fabricated material. Bolts with large washers were used to fasten
panels together. The main construction materials are 2 X 4" lumber and
composition board.
-54-
Figure 24. "Army" building.
Discarded debris in the vicinity included a pile of well used lead-acid
batteries, various sizes and type of electrical wire (some had the insula-
tion burnt off as part of a salvage operation), mesh wire, pieces of
furniture, miscellaneous automotive parts, pieces of a fishing net with
floats, a Chevrolet pick-up truck and miscellaneous food and beverage con-
tainers. A small freshwater spring was noted at the base of the ridge
25 m east of the houses.
A National Park Service ranger station, campground and trail-head parking
are located on the west side of the Skagway-Dyea road at mile 8.3 (#20).
The ranger station consists of three temporary plywood buildings, a gravel
parking lot and a road winding through the willows to a location where
tables, toilets and fire areas are provided. The entire area is located on
the Taiya River flood plain.
-55-
A small marine shell deposit was discovered 50 m south of the 8.0 mile post
on a small rock bench 3 m above the road (#21, Figures 25 and 26). A
careful visual examination of the exposed portion of the deposit failed to
identify any indication of cultural material. However, no digging was done
at the site so only a small portion of the deposit could be seen. The
deposit is more completely described in Appendix B-2.
-56-
Figure 25. Marine
shell deposit.
Figure 26. Marine
shell deposit.
A small occupied house, outbuilding and animal corral are located 75 m
east of the 8.0 mile post (#22).
South of the 8.0 mile post the road traverses the edge of Taiya Inlet on a
bench blasted out of the hillside. Two widely spaced north-south transects
were surveyed in a basin area approximately 300 m above the road. The main
reason for covering the area was to investigate a mine (prospect) shown on
the topographic map (Skagway B-1 Quadrangle, T27S. R59E. Sec. 35). The
prospect was not located. but it is most likely outside of the proposed
development corridor.
An occupied trailer is located just east of the Skagway-Dyea road at
7.2 mile (#23).
At mile 6.6, a single steel" wire telegraph/telephone line was discovered
(Figure 14). The line is broken and ends 25 m uphill (east) from the
roadway. The line angles towards the ridge top on a bearing of S38°E (UTM
N6593300M/E480450, T27S, R59E, Sec. 34). At the top of the ridge (UTM
N6593250M/E480650M, Sec. 34) the line's bearing changes to S45 0 E for
approximately 100 m down into the Long Bay drainage where its route was
lost (Appendix B-3). This line may have connected Skagway and Chilkoot
Pass with Dyea, as described in an 1898 newspaper item in the Dyea Trail
entitled, "Sunset Telephone Company--communications with Skagway and all
points on the Dyea Trail" (Spude, 1980:37).
An attempt was made to find additional intact sections of line. but road
building and other activities along the route has damaged the line. Three
short pieces (less than 10 m) of wire and one white ceramic insulator were
found just above the road between 8.0 and 6.6 mile. Three short isolated
pieces were found in the 5.5 mile area west of Long Bay and a short piece
of similar wire was found north of Dyea running parallel to the Chilkoot
Trail. No additional sections of intact line were found. A NPS ranger
familiar with the upper sections of the Chilkoot Trail indicated that long
lengths of wire are still visible; however. the insulators are gone. at
least on the sections of line on or near the trail.
-57-
Figure 27. Green glass insulator on line
from Long Bay to Skagway.
Two small occupied cabins or sheds overlooking the Taiya Inlet at 6.3 mile
are visible from the road. Access is by a short driveway to the west of
the road (1125).
Three houses were observed at the head of Long Bay at 5.1 mile (#26). A
log cabin and conventional house are located to the north of and within
10 m of the road. Rick Burroughs, who lives at the cabin, thought it was
built in the 1940's. An unoccupied "A" frame house is 75 m to the north
of the road and about 50 m northwest of the large house.
There are numerous out-buildings (woodsheds, old root celler, garage, power
plant, and storage sheds) associated with this group of houses. The area
between the road and the beach is densely covered with vegetation. There
is a small pit 20 m south of the log cabin. It contained a-small amount of
recent trash, mostly food and beverage containers. No other features were
associated with it and its age probably corresponds with that of the log
cabin. This strip of land also has a recently constructed mesh wire pen
for small animals (goats) and a small fenced garden plot-.
-58-
There is an occupied house on the beach at Long Bay below the road at 5.3
mile. Access is by trail from the road (#27).
Long Bay to Skagway
The section of the transmission line corridor between Long Bay and Skagway
traverses a steep rocky ridge on the north end before the ridge flattens
out near its southern terminus at the Skagway River. Surveys were not
conducted in the northernmost area as steep topography made the presence of
cultural resources unlikely and foot travel was dangerous. Transects
paralleling the Skagway-Dyea road were used to survey the corridor from 4.5
mile south to the Skagway River.
The surveyed area contained only contemporary cultural resources. Informa-
tion gained from literature and local informants indicates there was very
little, if any, gold rush activity in this area.
The Skyline Trail begins just north of the Skagway-Dyea road (#28, Figure 28).
This ridge trail provides hiker access to the alpine region of AB mountain.
The trail forms the eastern boundary for a four-acre parcel of patented
property belonging to Elizabeth Selmer of Skagway. The property lies west
of the trail and includes an outhouse and remains of a burnt cabin 50 m
northwest of the trail head. All of the material in this area is recent.
A small shed at the Skyline Trail head (20 m northeast of road, Figure 29)
was placed there by a person trying to patent that area (#28). An addi-
tional occupied cabin was noted 200 m north of the Skyline Trail (#29).
Background information on the status and activity of the Skyline Trail
area was provided by Elizabeth Selmer.
Southwest of the Skyline Trail (Figure 28), a road provides access to a
rifle range, a small cove north of Yakutania Point (road is blocked to
vehicular traffic) and to the Skagway River northeast of Yakutania Point.
A well-traveled trail leads from the rifle range to the remains of a sus-
pension foot bridge (#30) on the Skagway River. The trail passes two
large pieces of cable (4.5 cm diameter) which are anchored in a rock face.
-59-
Figure 28. Skyline Trail -
Skagway area
Legend
• Shed
-Road
Trail
F( Bridge
+ Cemetary
1" :: 50 m
o SOM 100M
S,C.ALE..
COile.
/
/"
/
/
/
/S~'-'\LlNE
./ /" ,,zP\\L
;'
/:#=-~e
-60-
Figure 29. Cabin
at Skyline Trail
trailhead.
Remnants of a wooden boardwalk were noted. Wooden timbers bolted together
to form a bridge frame were visible on a small willow covered island in
the Skagway River (Figure 28). The bridge was for foot traffic only and
was removed when the main highway bridge was constructed upstream from
Skagway.
2 A small pet cemetary (10 m) (#31) with 13 graves is located 15 m above the
bridge-cables. MOst of the graves are enclosed by a water pipe frame that
stands 20 em off the ground and is painted silver. MOst graves had metal
name markers, one was wood, one wood cross, one marble marker (was broken
and unreadable) and two were unmarked. Two grave markers provided the
dates of 1958 and 1980. The 1958 marker has a round brass Skagway dog tag
tacked on the marker.
Alternate Transmission Line Corridors
Two alternate transmission line corridors are under consideration by R.W.
Beck and Associates, Inc.; one from the powerhouse along the west side of
the Taiya River valley and the second from the powerhouse site Over the
mountains to the west, directly into Haines.
-61-
The alternate corridor along the west side of the Taiya valley did not
receive as complete a survey as the primary route on the east side of the
Taiya River. However, the area from the powerhouse site to the tide
flats was surveyed by foot-travel along roads and trails.
Moving south from the powerhouse, the first mile of corridor contained
several occupied and abandoned residences. Most of the material appears to
be recent (1940-50's), however, it is possible that some of the buildings
may be older.
From the southern end of Section 22 to a point several miles south of the
Dyea townsite there is evidence of gold rush activity, particularly in the
area adjacent to and south of the townsite. Remnants of the DKT dock, the
toll bridge and wagon are still visible, according to Spude (1980:177).
The survey team did not cover any of the DKT area. There are also several
residences and garden plots in this section of the corridor. Four resi-
dences were noted in the valley and one was reported on the hillside. Due
to the area's close proximity to Dyea, it is qui.te possible that some, if
not all, of these dwellings date from the 1898 period. The entire lower
mountain slope through this area was logged heavily in the early part of
the century.
The second alternate route (traversing the mountains to Haines) was not
surveyed due to the difficulty of access in rugged terrain. The area has a
very low potential for cultural resources.
POTENTIAL FOR IMPACT AND MITIGATION RECOMMENDATIONS
This evaluation addresses the potential for project impacts and mitigation
for the defined survey areas. Future rerouting of hydroelectric project
development into areas outside of the surveyed corridor would require
additional surveys prior to ground disturbance.
-62-
West Creek Drainage
The survey did not reveal any cultural resources within the dam site or
reservoir. The possibility of mining claims along the periphery of the
reservoir area does not warrant any further investigation at this time.
However, during any vegetation clearing activities which accompany con-
struction, surpervisory personnel should be on the alert for signs of
small mining operations. If cultural remains are located, further surveys
should be made to determine their extent. The remainder of the dam site
and reservoir area should not require further investigation or mitigation
efforts.
No resources of cultural significance were identified within the areas of
the power corridor which were surveyed. These areas included the west end
near the dam site, the east end near the powerhouse site, and the approxi-
mate location of the powershaft access road. For non-surveyed areas along
the power corridor, it is recommended that an archaeologist should investi-
gate if there are future plans for ground disturbance in this area. Crews
should notify a designated person whenever cultural materials are discovered
that were not noted on the original survey.
Taiya River Valley
No significant cultural resources were observed at the power house site near
the confluence of West Creek and the Taiya River. However, additional
archaeological investigation is recommended if the site is relocated during
subsequent planning and/or if surface disturbance activities occur outside
the surveyed area during construction of access roads, staging areas, and
other ground disturbing activities.
The primary transmission line corridor across the Taiya valley will cross
the Chilkoot Trail and areas of gold rush activity. Placement and design
of the transmission line in this sensitive area, and as it transects the
valley, will require consultation with and approval from state and federal
regulatory agencies. Additional information will be required before final
impact assessment and mitigation measures can be completed. Necessary
design information would include, at least, the exact route to be traversed,
-63-
type of line (buried, elevated, or a combination) and projected maintenance
and right-of-way requirements for each line section. Additional archaeolo-
gical investigation is recommended for the exact location at which the
line will bisect the Chilkoot Trail.
Aligning the transmission line along the existing Skagway-Dyea road would
result in the least cultural impact. In many cases the disturbance caused
by road construction appears to have been extensive. However, the use of
all or part of the road corridor would not eliminate additional planning
of mitigation measures prior to route approval.
An elevated tran~mission line would minimize the impact on cultural remains
in sensitive areas. However, the visual impact of the elevated line must
also be considered.
Sections of the corridor in the Taiya valley will cross private parcels of
land, some of which have had considerable land alteration. It is possible
that cultural resources may have already been disturbed in these areas.
Parts of the private property, especially around areas of disturbance,
were not surveyed.
Four additional areas within the eastern Taiya River valley which warrant
consideration include (a) the modern Chilkoot Trail and Trailhead, (2) the
group of structures east of the Skagway-Dyea road at mile 8.4, (3) the NPS
ranger station at 8.3 mile, and (4) the marine shell deposit at mile 8.0.
The avoidance of these areas during routing will eliminate the need for
further investigation and mitigation. It is reeommended that a more inten-
sive investigation be conducted at the mile 8.4 houses and the 8.0 shell
deposit should it be necessary to route in the immediate vicinity of these
features.
East Ridge to Skagway
In the Taiya River to Long Bay section of the development corridor, the
only significant cultural resource located was the steel wire line over the
ridge. Impact on this site can be eliminated by avoidance of the area. If
this is not feasible, the line should be marked and act~vity in the imme-
diate area designed to avoid the trees supporting the line.
-64-
In the Long Bay to Skagway section there are two areas of sensitivity which
should be avoided to eliminate disturbance. These include the shed and
trail head area for the Skyline trail and the pet cemetary and suspension
bridge remains near the Skagway River. While neither might be classified
as significant resources, their avoidance would eliminate possible problems.
Alternate Corridors
It is recommended that the alternate route along the west side of Taiya
River valley receive a more thorough archaeological-historical survey if
this is selected as the preferred route. The close proximity of this route
to historic Dyea, passage through NPS administered lands, and high visi-
bility suggest this route may be more sensitive and difficult to mitigate
than the east Taiya valley route emphasized in this survey.
The high mountain corridor to Haines would also require an intensive survey
and mitigation program if it was selected as a preferred transmission
route. Higher elevation areas may be sufficiently surveyed by helicopter,
with on-ground survey limited to less difficult access areas where there is
greater potential for cultural remains.
-65-
REFERENCES
Car1ey~ C.D., 1981. Assessment of Cultural Resources in Klondike Gold Rush
National Historical Park. Reconnaissance Report 40. Office of Public
Archaeology, University of Washington, Seattle.
Goldschmidt, W.R. and T.H. Haas, 1946. Possessory Rights of the Natives of
Southeast Alaska. Report to the Commissioner of Indian Affairs.
Mimeographed.
Krause, A., 1885. Die T1ingit Indianer. Trans. by Erna Gunther, The
T1ingit Indians. University of Washington Press, Seattle. 1956.
Oberg, I., 1973. The Social Economy of the T1ingit Indians. University of
Washington Press, Seattle.
Sea1aska Corporation, 1975. Native Cemetary and Historic Sites of South-
eastern Alaska.
Spude, R.L., 1980. Chi1koot Trail. Anthropology and Historic Preservation,
Cooperative Park Studies Unit, University of Alaska, Fairbanks.
Swanton, J.R., 1980. Social Conditions. Beliefs. and Linguistic Relation-
ship of the T1ingit Indians. Bureau of American Ethnology, 26th
Annual Report. Washington, D.C.
Viereck, L.A. and E.L. Little, Jr., 1972. Alaska Trees and Shrubs. U.S.
Forest Service, U.S.D.A., Agriculture Handbook No. 410. Washington, D.C.
Yehle, L.A. and R.W. Lemke, 1972. Reconnaissance Engineering Geology of
the Skagway Area, Alaska. U.S. Department of Interior, Geological
Survey, Open file report.
-66-
FISHERIES INVESTIGATIONS
FOR WEST CREEK HYDROELECTRIC PROJECT
PURPOSE
The principal objectives of this work were to:
1) Determine the extent of anadromous salmonid use of
West Creek and its tributaries and to evaluate the
existence of rearing fish populations.
2) Determine fish use of West Creek above the lower gorge.
3) Collect available information on Eulachon (Thaliechthys
pacificus) runs at or near the mouth of West Creek ..
4) Collect available information on salmonids in the
Taiya River channel within one-half mile below the
confluence of West Creek.
5) Describe the stream channel habitat and substrate
conditions in West Creek (a) between the lower gorge
and the confluence with the Taiya River and, (b) in
upper reaches of West Creek used by salmonids,
particularly Dolly Varden (Salvelinus malma).
Scope of Report
This report presents results which address the objectives outlined above.
The limited nature of fishery impacts resulting from the West Creek hydro-
electric project is discussed herein, and measures to protect, mitigate or
enhance fishery values are examined.
-67-
METHODOLOGY
A reconnaissance by Mssrs. Dan Bishop and Alex Milner was made on 16 and
17 July, 1981. From this investigation, four small tributary streams
entering West Creek above the lowest gorge were identified and designated
(Figure 30) for minnow trapping. This work was designed to determine if
anadromous or landlocked fish specie(s) were present above the lower
gorge.
Two-foot, galvanized wire minnow traps baited with boraxed salmon eggs
were fished for two hour periods in three tributaries, while the fourth
tributary (across West Creek and immediately above the dam site) was
fished for only 40 minutes because of helicopter scheduling. Ten traps
were deployed by S. Elliot (ADF&G), M. Schwann (ADF&G), and Joe Wallmo,
party to this investigation, in each of the two tributary channels of the
middle basin (within the c1earcut) on 27 August. Twelve traps were used
in the tributary entering West Creek one mile above the dam site and eight
traps were used in the small stream entering from the south immediately
upstream of the dam site on 11 September by D. Bishop and J. Wa11mo.
Periodic examinations were made of the clearwater tributary entering West
Creek immediately downstream of the West Creek Bridge. Counts were made
of Dolly Varden seen in a pool of this tributary.
During the entire survey period the flows of both the Taiya River and West
Creek were high and waters were turbid, restricting visibility from the
stream banks.
Individuals contacted as part of the fishery investigation included:
Dave Canti11ion -Regional Biologist, Commercial Fisheries Division,
ADF&G.
Discussed potentials and problems of a hatchery on West Creek.
-68-
Figure 30. Location of tributaries examined
for fishery habitats.
INU:RVAt 10011
Dave Clabaugh -Ranger, Klondike Gold Rush National Historic Park.
Discussed runs of Dolly Varden into West Creek and Eulachon
into Taiya River and lower West Creek.
Skip Elliot -Skagway City Manager.
Discussed distribution of fish populations in West Creek
drainage.
Steve Elliott -Biologist, Sport Fish Division, ADF&G.
Conversations regarding his observations made 27 August
while minnow trapping in West Creek, and on age and condi-
tion of Dolly Varden samples taken from a small tributary
in the clearcut.
Bob Hackett -Dyea resident.
Brief conversation regarding fish populations native to
tributaries entering below West Creek bridge.
David T. Hoopes -Biologist, R.W. Beck & Associates, Inc.
Observations on fish habitat, stream conditions, fish
observations during reconnaissance 8-25-8l.
Alf Kalvick -Longtime Dyea resident.
Conversations regarding Dolly Varden and Eu1achon runs.
RESULTS OF FISHERIES INVESTIGATION
West Creek and Tributaries Above Upper Gorge
Reports by residents of Skagway and Dyea indicated that few if any fish
resided or spawned in upper gorge waters near the proposed dam site. No
fish were observed during examinations of these waters by members of this
study team or by D. T. Hoopes during his reconnaissance on 25 August, 1981.
No fish were captured during minnow trapping in two tributaries entering
this portion of the West Creek drainage (see Figure 30). Both of these
tributaries had sections and stream edges with ample area of gentle stream
velocities and with fine gravel bed material suitable for spawning.
No attempts were made to trap fish in the fast turbid waters of West Creek
above the dam site. If fish reside in this upper basin, they are most
likely to be found in clearwater tributaries.
-70-
The gorge below the proposed dam site contains a series of cataracts and
chutes with sustained high velocity conditions (see Figures 31, 32 and
33). Upstream migration of sa1monids is likely to be greatly limited or
prevented, at least for the period of high flows from May to November.
West Creek and Tributaries in Middle Basin
Several local people reported fish in two small mountain drainages entering
West Creek as it passes through the up-river portion of the c1earcut.
Trapping on 27 August by S. Elliott, M. Schwann1 / and J. Wa11mo supported
these reports as did observations by D. Bishop and n. T. Hoopes. Dolly
Varden were present at very low density levels (some of the lowest in
Southeast Alaska) and representative samples of fish were aged at 3 years.
Elliott believes this population is probably resident (land-locked).
These two small streams join into a lower section with gentler gradient
before entering West Creek. There is ample good quality spawning gravel
in the lowest portion of these tributaries. Iron staining in the gravels
indicate that this lower part of the tributary receives flow from upwelling
groundwaters.
West Creek flows at high velocity without relief in this middle basin be-
tween the upper and lower gorges. The streambed is dominated by boulders
and cobbles. There is little, if any, rearing or spawning habitat in this
channel.
Lower Gorge of West Creek
This extended section of rapids and falls is bordered and confined by
steep slopes or rock walls. The flow, as seen from the adjacent northerly
slopes, provides absolutely no access for fish traveling up the stream
bottom. No slow flowing water areas were seen (see Figure 34). Blockage
to fish migration upstream may be more a function of sustained high
velocities than a result of a particular falls or rapids .
. Elliott and M. Schwann are ADF&G fisheries biologists with the
Sportfish Division, Juneau.
-71-
Figures 32 and 33.
Figure 31 .. Rapids be] Ow'
JC!J'lsi te.
Cataract areas below darnsite. Drop in lowest cataract
shown in Figure 34 is 1. 2 to 1. 8n.
-72-
West Creek Between Lower Gorge and Taiya River Confluence
The single tributary joining West Creek in this section enters the main
stream immediately below the West Creek Bridge. This tributary is fed by
a mountain stream, by local areas of upwelling spring flow, and by flood-
waters during high flows of the Taiya River (Figure 35). There is no
evidence that any significant fraction of this tributary's flow derives
from surface or groundwaters of West Creek.
This tributary supports anadramous Dolly Varden. Adult fish were ob-
served congregating in a pond on the stream which is probably spring fed •
. Two counts were made of fish in the pond: 60 and 48 Dolly Varden were
counted, respectively.
This tributary stream may also support a few fall chum (Oncorhynchus keta) ,
and coho (~kisutch) salmon, although local residents have not seen them
in this stream" and none were seen during this investigation.
Shorelines of Lower West Creek and Taiya River
Turbidity of water generally prevented any meaningful observations along
the shorelines of lower West Creek and the Taiya River within one-half
mile downstream of the confluence. However, when the stream was visited
on 30 October, 1981, water clarity had begun to improve. An examination
of the shoreline near the mouth of West Creek showed no spawning salmon,
though a chum salmon carcass from up the Taiya River was caught in log debris
on the river below the West Creek confluence. West Creek, near its con-
fluence with the Taiya River, was neither minnow trapped nor seined for
possible resident population.
West Creek below the lower gorge is shown on Map 1, and prominent streambed
and streamside conditions are indicated.
Eulachon Spawning Habitat in Lower West Creek Vicinity
The Eulachon runs of the lower Taiya River also extend into the West Creek
confluence during some springs. The possible impact of regulation and
alteration of West Creek's stream flows upon Eulachon spawning is very
-73-
-74-
'cries of falls ~nd
'cl?Lds in iJest Creek
lower gorge directly
upstream from Taiya
River valley"
Figure 35. Tributary which
enters West Creek
below bridge.
Dolly Varden foun~
in pools.
difficult to assess. It is conceivable that timing or location of Eulachon
spawning may be altered during some springs by the influence of changed
temperature and volumes of West Creek waters. This possibility cannot be
evaluated at this time, due to both the minimal information available on
West Creek's Eulachon run, and the present lack of stream temperature
information. A summary of Eulachon life history is provided so that some
insight might be developed concerning the possible role of Taiya River
flow conditions in influencing Eulachon spawning runs.
Eulachon (Thaleichthys pacificus) are Pacific smelt which spend two to
three years in marine environments, then migrate to rivers and streams of
the Pacific Coast from northern California to northern southeast Alaska.
These silvery fish range in length from 125 to 200 mm at 2-3 years of age.
They are exceedingly rich in oil and have been traditionally rendered for
cooking oil by coastal and near-coastal Native peoples of the Northwest
and Alaska.
Spawning of Eulachon in Lynn Canal-Taiya Inlet streams occurs in early
May, and is evidently of shorter duration than in more southerly streams
(i.e. southern British Columbia). Great numbers of fish, probably domi-
nated by two-year olds, enter the sandy mouths of rivers to spawn.
Fertilized eggs evidently settle upon the sandy bottom and become indi-
vidually attached to sand grains through an external membrane. Newly
hatched larvae are weak swimmers and probably migrate with currents back
into the estuary.
Eulachon streams in southeast Alaska are exclusively mainland rivers, with
significant contributions by glacial meltwaters and high sediment loads.
The early May spawning period to which Taiya River Eulachon are adapted
would provide conditions with increasing volumes of meltwaters and suspended
sediment load, and with water temperatures which are likely to fluctuate
diurnally, but remain at relatively low levels. As yet, no information
has been found which discusses or identifies the ecological requirements
of spawning Eulachon.
-75-
POTENTIAL IMPACTS ON FISHERIES
The construction of a dam and a reservoir in upper West Creek will destroy
no fishery values in that part of the watershed as none have been found to
exist. The proposed impoundment will inundate the lower portions of both
upper drainage tributaries which were fished with minnow traps during this
study. It is possible that some potential spawning and rearing habitat
may remain in one or both of these clearwater tributaries above the limit
of reservoir water, athough this has not been verified with accurate
engineering data determining the reservoir limits. Such potential habitat
would be useful if stocking the reservoir with fish was attempted.
The reservoir waters are likely to be considerably less turbid than present
stream waters, with only colloidal sized particles remaining in suspension
near the lower end of the impoundment. Stream velocities will, of course,
be radically reduced in the reservoir area.
The portion of West Creek between the dam and the powerhouse may be
subject to highly variable flow conditions ranging from very low flows
(likely in winter), to sizeable or large releases at other times of the
year. No fish are known to reside in or migrate through the mainstream of
West Creek above the lower gorge. However the two small tributaries of
the middle drainage which contain fish in their lower section may be
affected. Impact could result from partial loss of tributary channel
flows to groundwater because valley sediments are no longer saturated.
Occasional resident Dolly Varden from the two above mentioned tributaries
probably drift into the mainstream and are swept out of West Creek by high
flows. Greatly reduced flows will allow fish caught in the mainstream to
find pools and eddys in which to reside, at least temporarily.
The lower gorge of West Creek presently contains no fish habitat. Develop-
ment of a hydroelectric facility could result in pools in portions of the
gorge. These pools may be attractive to fishermen, seeking Dolly Varden
which may colonize these waters.
-76-
West Creek below the lower gorge and the proposed power house site contains
no identified salmonid habitat, although the stream does provide an access
route of several hundred yards by which anadromous Dolly Varden and pos-
sibly a few chum salmon reach the mouth of the tributary stream (see
Figure 37). There is no reason why this migration route need be disturbed
as a result of powerhouse installation and routing of tail race water back
into the stream channel. Stadia traverse information on the lower stream
section has been provided to assist with evaluation and facility design.
The possible impact of West Creek flow regulation upon Eulachon spawning
in the Taiya River has not been analyzed. A meaningful body of informa-
tion is simply not available. Most importantly, the spawning preferences
or requirements of Eulachon have not been determined, and no agency or
group interest in such work fundamental to habitat protection or management
has not been identified.
PROTECTION, MITIGATION AND ENHANCEMENT
The limited number of Dolly Varden present in the middle basin of West
Creek are probably resident and stunted in growth. No protective measures
are recommended for this population as it will probably survive habitat
alterations.
It is possible that some pools in the de-watered channel would become
habitat for resident fish. Fishermen using such pools should be protected
from sudden releases of water from the dam.
The natural alluvial channel below the powerhouse and lower gorge on West
Creek should be maintained so that fish migrating upstream from the Taiya
River have access to the small tributary entering West Creek below the
bridge from the north. It appears unlikely that such a requirement would
necessitate additional mitigation beyond returning tail race water into
the West Creek channel. This will be better established after a map and
profile of the stream section is completed.
-77-
The proposed West Creek project would provide a potential for a salmon
hatchery water supply. The possibility of establishing a hatchery at the
head of Taiya Inlet was discussed several years ago both by the Northern
Southeast Aquaculture Association and by the Alaska Department of Fish and
Game. The water taken from the lower depths of the reservoir water supply
o would be cold (4-6 C), poorly buffered (low conductivity, alkalinity, and
hardness), and milky. These conditions, and the apparent infertile
nature of the Taiya Inlet entry, could limit the usefulness of the site
for a hatchery. The objectives and operation of such a hatchery must also
address the species and timing of the returning run. For example, a
sizeable hatchery run of late chum salmon would create serious diffi-
culties in ADF&G management of the fall Lynn Canal fishery. On the other
hand, an earlier run of salmon, possibly harvested in Taiya Inlet, might
be compatible with harvest management strategy. The species composition
and run timing which would be feasible and desirable for a West Creek
hatchery must be determined before a decision is made to design and install
a tap off the penstock or other hatchery water supply possibilities.
Finally, there is the possibility that the tail race and lower West Creek
flow route(s) could be designed so that salmon running into the Taiya River
would be attracted to the channel for spawning. The concept of such a
design would be to utilize a regulated (or partially regulated) flow
derived from all or part of the tail race water to develop a salmon
spawning channel. While this concept has been used in British Columbia
projects, there has been no indication to date of support by the Alaska
Department of Fish and Game or the Northern Southeast Regional Aquaculture
Association for such efforts. Nevertheless, a significant potential may
exist.
-78-
APPENDIX A-I: SELECTED PHOTOGRAPHS OF WILDLIFE SURVEY AREA AND
HABITAT
B.
A. North wall ot west creek valley. Goat slgn
most abundant above timber between arrows. ~~--------------------7~
Steep timbered slopes used as
winter goat habitat.
c. At right, brushy timber-alpine
ecotone at X on Photo A.
D. West wall of "Glacier Creek" valley.
~observed to most abundant from arrow
• '!.
Goat use
to arrow •
E. North wall of West creekl
F. Looking south up "Glacier Creek" valley,
saddle above Burro Creek at center.
APPENDIX B-1: INTERVIEW DATA
1) Burroughs, Rick -Long Bay area resident.
The survey team spoke with Mr. Burroughs at his log cabin on the
northwest shore of Long Bay, where he has resided for seven years. He
represents part of the recent growth of Taiya valley population; pre-
viously, Mr. Mathews and Mr. Patterson were the only permanent residents.
Mr. Burroughs called our attention to a small debris-filled hole
across the Skagway-Dyea road from his cabin.
2) Clabough, David -Ranger. Klond"ike Gold Rush National Historic Park.
The survey team talked with Mr. Clabough on several occasions during
the survey period, and on one occasion we patrolled the Dyea area with
him. We visited the old Dyea cemetary and discussed the ~ount ~nd
rate of erosion that has been taking place in the vicinity of the
cemetary and the native village site that is reported to be in the
area. He was also able to provide general information on the gold
rush era houses/cabins that are still occupied in the area, and on the
location of visible remains of DKT Company activity southwest of Dyea.
3) Elliott, Skip -Dyea area resident. Skagway city manager.
We met with Mr. Elliott in his office at the Skagway City Hall and
discussed a map he had located in old city record books that indicated
there were mining claims in upper West Creek valley. He felt that
most would be well above the proposed project area. Mr. Elliott had
made several unsuccessful attempts at trying to locate the claims.
When asked about a possible historic native trail route from West
Creek basin into the Haines area, he said a traverse would be possible,
but the route would be very difficult. Mr. Elliott's familiarity with
the West Creek drainage was a great asset in evaluating the potential
for cultural sites in the area. In addition to the possible mining
claims in West Creek, Mr. Elliott noted that the entire ridge south
and east of Skagway was covered with mining claims, even though there
is no gold there.
4) Hosford, Fred -Skagway resident.
Mr. Hosford's father logged in the Taiya River valley from the 1940's
into the 1960's and the family owns property at West Creek near the
powerhouse and tail race. The sheds and debris in the powerhouse
area date from the 1950's. Mr. Hosford remembers the larger shed
being occupied by an elderly man in the late 1950's, early 1960's.
The evidence of logging in the powerhouse site and transmission
corridor was done by the Hosford family in 1965.
5) Ka1vick, Alf -Dyea area resident.
The Kalvick's live on the main road near the junction with the road
to the powerhouse. They have built their home, outbuilding and other
improvements in four years. Their property backs up to the McDermott
property to the east. Mr. Kalvick was able to provide information on
gravel depth from information he gained while putting in his well.
He also provided information on the construction methods of the main
road. Over the course of the survey several visits were made to the
Ka1vick's and stories of the area were enjoyed around the fire or at
least out of the rain.
6) McDermott, John and Lorna -Dyea area residents.
The McDermotts live in an 1898 log cabin along the Chilkoot Trail.
The cabin has been modified and some major repair work has ~een done.
The area around the cabin has been cleared and fenced for gardens and
animals. The cabin has been occupied only periodically over the
years, but appears to be well-maintained. The McDermotts confirmed
the location of the historic Kinney Bridge to the north of the cabin
on the east side of the Taiya River.
7) Rapuzzi, Bob -Skagway resident.
Mr. Rapuzzi described an historic native trail that ascended the south
side of West Creek and traversed the mountains to the Chi1koot and
Chilkat drainages (Haines area). He did not know how frequently the
route had been used, but indicated there were some rugged sections.
Mr. Rapuzzi was not familiar with possible past military activity on
the north side of the Skagway River, but indicated activity in that
area was sparse in the 1890's. Development of the north side of the
river occurred in later years, primarily after the construction of the
Skagway-Dyea road. At one time, there was a cable which crossed the
Skagway River near the 3.0 milepost. Mr. Rapuzzi indicated that the
rock quarries along the southern edge of Yakutania Point were used to
obtain fill material for the Skagway tide flats.
8) Selmer, Elizabeth -Skagway resident.
Contact was originally made with Ms. Selmer to obtain information
about her 4-acre property west of the Skyline Trail. Ms. Selmer
originally improved her property to receive a patent, but her cabin
burned some years ago. She indicated the shed located near the Skyline
Trail was also constructed by an individual seeking to patent the
area. Ms. Selmer recalled that the cables evident near the Skagway
River were originally part of a suspension foot bridge. She thought
the bridge was removed when the present Skagw~y airport was expanded.
The only sign of military activity Mrs. Selmer recalled was a large
antenna on Yakutania Point. She commented that the military was
primarily interested in the White Pass and Yukon Railroad on the south
side of the Skagway River.
APPENDIX B-2: MARINE SHELL DEPOSIT
This small marine shell deposit does not appear to contain cultural
material, however, only the exposed surface was investigated. The road has
cut into the deposit and it continues to erode. It is suggested that this
deposit receive additional attention before any project activity in the
area.
The shell deposit is located 50 m south of the 8.0 milepost along the
Skagway-Dyea road. The deposit is located on the top of a 3 m high rock ,
face which was formed during road construction. An unknown amount of shell
material was lost during construction.
The deposit is composed mostly of mussel shells, with a few gastropods
(.5 cm to 6.5 cm dia.), limpets, fish verterbrae and small bones. The
visible stratigraphy of the deposit appears to divide it into three rela-
tive distinct layers. The top layer is mixed with forest humus with small
roots and averages 40 to 60 cm in depth. The middle layer is densely
packed mussel shell and is from 10 to 40 em in depth. The bottom layer has
a variety of shell material (mostly mussel), sand, old humus, and small
piece~ of charcoal. This layer is from 5 to 30 em in depth.
The width of the exposed deposit is approximately 5 m, but all three layers
do not extend the entire width. While the surface of the site is under a
dense moss and humus cover, its approximate size is estimated to be 3 to
4 m2 . The deposit is about 3 m above the road bed which is 2 m above the
river level. It should be noted that these measurements are not referenced
to the mean tide level.
While this deposit is within the transmission line corridor, the small size
and close proximity to the road make it easy to avoid. If there will be
any disturbance to the area, further investigation should be considered.
APPENDIX B-3: SINGLE STEEL WIRE LINE
The following table describes remnants of the steel wire line located on the
ridge east of the Taiya River valley. The type of insulator, tree species
used for supporting pole and condition of the wire at the pole/insulator.
Insulator No.1 is located 10 m above the Skagway-Dyea Road at 6.6 mile. The
line between No.1 and No.8 leads from the road to the ridge top at a
bearing of S38oE. Between No.9 and No. 11, the line drops down into the
Long Bay drainage at S450 E. The remnant line ends just beyond No. 11.
Insulator No. Insulator TY:2e SU:2:2ortins Tree Line Condition
1 green glass Sitka spruce Broken on downhill
side.
2 green glass lodgepole pine Hanging on wooden
insulator support.
3 white ceramic lodgepole pine (dead) Line is up.
4 white ceramic not on tree Wire down but unbroken.
5 green glass lodgepole pine Broken and down.
6 green glass lodgepole pine Line is up, though
a tree is lying
across line.
7 green glass lodgepole pine Line is up.
8 white ceramic lodgepole pine Line down and broken.
9 white ceramic lodgepole pine Line i~ up.
10 white ceramic lodgepole pine Wire is on insulator,
but is broken.
11 green glass not on tree Insulator hanging free.
Note: Long spans noted between Nos. 2-3 and 5-6 indicate insulators
may be missing between these points.
I I T
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I t
I I
,--J_ -L_ --. ..l
W~\T€ CeAAI'''1.IC
tN"5>uL..A~
White Ceramic: No. identifiable markings
r------,
I ,
I I
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Green Glass: Raised letters near bottom "w. BROOKFIELD NEW YORK"
T
1
APPENDIX C-l: MEMORANDUM FROM S. ELLIOTT RE DOLLY VARDEN POPULATIONS,
WEST CREEK
MEMORANDUM
TO l"1ark Schwan
Assistant Area Biologist
Sport Fish Division
Juneau, Alaska
FROM Steve E I I i ot
Fishery Biologist
Sport FIsh DIvisIon
J un ea u , A I as ka
State of Alaska
DATE September 30, 1981
FILE NO:
TELEPHONE NO 465-4270
SUBJECT West Creek Do I I Y Varden Samp I es
I performed age analysis using the otol ith method on "rearing" char
captured in two tributarIes of West Creek (8/18/8[/) to determine the
compositIon of resident (non-anadromous) char.· Pigmentation was also
used as a criterion to separate resident from anadromous forms.
Age-length composItion of Dolly Varden from both tributaries (see attached)
fell intc the range normally found in anadromous populations (Ell iott,
1974). Body coloration was also typical of anadromous populations and
did not Indicate the dark pigmentation common to resident forms during
the fal I.
Catch rates (catch/trap/min.) were significantly dIfferent in the two
streams. This reflects a difference in fish density and habitat; the
upper stream representing margInal habitat with low fish density per
-linear distance as compared to more diverse, stabi Ie habItat with higher
fish densIty in the lower stream.
In summary, I would characterize the two streams as fol lows:
Lower Trl butary
12-001 A( Rev.1 0/79)
Sprlngfed with stabi Ie habitat features; supports a moderate
density of juvenile anadromous char.
No coho were captured, even though traps were set in habitat where
they would most I ikely be found.
The stream has pools which may remain Ice free during the winter
and may harbor overwintering char of catchable size. These fIsh
are most I ikely to be Taiya or West Creek spawners that overwinter
in deep pools and outmigrate in the spring.
Mark Schwan -2-September 30, 1981
Upper Tributary
No coho were found In the stream.
Very marginal habItat supportIng a smal I number of char. Streams of
thIs type typically support populations of nonanadromous char at
low densities and growth rates. The stream has an InsIgnificant
contribution to annual production of char by West Creek. Development
In thIs area, even eradIcation of stocks In this tributary, would
not affect the strength of West Creek -Taiya stocks.
cc: Dan Bishop
enclosures
.. ~
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
Age 0
WT F.L.
-0-
x
S.E.
S.D.
N=
CPUE = .027
S.D. = .042
Age
WT
2.7
1.9
3.4
2.8
2.0
3.4
1.9
2.0
1.9
2.3
2.9
2.9
1.9
2.3
2.45
.14
.55
14
SPRING FED STREAM
I Age II Age III
F.L. WT WT F.L.
62 9.2 97 -0-
54 11.8 100
66 11.4 105
62 5.4 80
57 7.1 86
68
58
54
57
-61
63
65
58
60
60.3 8.98 93.6
1.14 1.22 4.6
4.2 2.74 10.3
14 5 5
Age 0
WT F.L.
-0-
x
S.D.
S.E.
N
CPEU = .006
S.D. = .007
UPPER TRIBUTARY TO WEST CREEK
Age I Age II
WT F.L. WT
4.0 72 6.5 86
1.8 55 9.5 102
3.5 70 11.0
1.8 57
2.7 63.5 9.0 96.3
1.14 8.7 2.2 8.9
.57 4.3 1.3 5.1
4 4 3 3
Age III
WT F.L.
18.4 121
13.2 109
17.2 115
162 115
2.7 6.0
1.5 3.46
3 3