HomeMy WebLinkAboutNaknek Service Area Wind & Solar Geotechnical Report - Feb 2009 - REF Grant 7013005Naknek Electric Association V3 Energy
DRAFT GEOTECHNICAL REPORT
Naknek Wind Turbines
Naknek, Alaska
February 25, 2009
Prepared By:
Trevor Crosby
Staff Geologist
HMHATTENBURG DILLEY & LINNELL
Engineering ConsuNenis
3335 Arctic Blvd., Ste. 100
Anchorage, AK 99503
Phone: 907.564.2120
Fax: 907.564.2122
TABLE OF CONTENTS
1.0 INTRODUCTION....................................................................... 1
2.0
SITE AND PROJECT DESCRIPTION ...................................... 1
3.0
LOCAL CONDITIONS.............................................................. 2
3.1
REGIONAL GEOLOGY AND SEISMICITY..................................................................2
3.2
TOPOGRAPHY, DRAINAGE AND VEGETATION........................................................2
3.3
CLIMATOLOGY.....................................................................................................3
4.0
FIELD INVESTIGATION...........................................................4
4.1
EXPLORATION.....................................................................................................4
5.0
LABORATORY TESTING........................................................ 4
5.1
LABORATORY TESTING........................................................................................4
5.2
INSTRUMENTATION.............................................................................................. 5
6.0
SUBSURFACE CONDITIONS .................................................. 5
6.1
SOILS................................................................................................................. 5
7.0
PRELIMINARY ENGINEERING ANALYSIS &
RECOMMENDATIONS...................................................................... 6
7.1
PILE ANALYSIS....................................................................................................6
7.2
ADDITIONAL CONSIDERATIONS............................................................................. 7
7.3
ADDITIONAL ANALYSIS......................................................................................... 8
8.0
CLOSURE AND LIMITATIONS ................................................ 8
LIST OF FIGURES
Figure 1 Location Map
Figure 2 Site Map
Figure 3 Allowable Pile Capacity
LIST OF APPENDICIES
Appendix A Figure Al
Figure A2
Figure A4-A7
Unified Soil Classification
Frost Classification
Borelogs
Appendix B Laboratory Test Results
Appendix C Ground Temperature Data
DRAFT GEOTECHNICAL REPORT
NAKNEK WIND TURBINES
NAKNEK, ALASKA
1.0 INTRODUCTION
The purpose of this report is to present the results of our subsurface
explorations, laboratory testing, and geotechnical engineering studies for the
Naknek Electric Association (NEA) wind turbine site in Naknek, Alaska. The
purpose of the field explorations was to define the soil and temperature
conditions for use in the design of the wind generation facility. Geotechnical field
studies were conducted on November 10th through November 17th, 2008. Soil
samples recovered from the field studies were classified in the field and later
returned to our laboratory for testing. Included in this report are descriptions of
the site and project, subsurface explorations and laboratory test procedures, and
interpretation of the subsurface conditions. Engineering studies were conducted
to develop our preliminary design recommendations. It is unknown at the time of
this report what type of wind turbine will be used. Once a selection has been
made and the design loads are known a foundation can be designed.
Preliminary pile capacities are presented in this report to aid in the selection of a
turbine.
2.0 SITE AND PROJECT DESCRIPTION
The proposed wind turbine site is located in Naknek, Alaska. Naknek is located
on the Alaska Peninsula in the Bristol Bay Borough, Alaska. The community lies
at approximately 58' North Latitude and 157' West Longitude. (Sec. 03, TOWS,
R047W, Seward Meridian.) Naknek is located in the Kvichak Recording District.
Naknek is located on the north bank of the Naknek River, close to where the river
runs into the Kvichak Bay arm of the northeastern end of Bristol Bay. It is 297
miles southwest of Anchorage. Naknek is accessible by air and sea, and
connects to King Salmon via a 15.5-mile road. The Tibbetts Airport in Naknek
has a lighted 1,700 foot long by 60 foot wide gravel runway. The State-owned
Naknek Airport is located one mile north of Naknek. it has a 1,950 foot long by 50
foot wide lighted gravel runway and a 2,000 foot float plane landing area. Jet
services are available at King Salmon. A location map is presented in Figure 1.
We understand that Naknek Electric Association currently favors two
approximately 700 kW turbines at or near the current met tower site at Cape
Suwarof. We understand that the final choice of the turbines used depends on
availability, cost, foundation considerations, and other factors. The met tower
site on Cape Suwarof is approximately 400 yards from the nearest road. A site
map is presented in Figure 2.
NAKNEK WIND TURBINES Page 1
Geotechnical Report
3.0 LOCAL CONDITIONS
3.1 Regional Geology and Seismicity
The Alaska Peninsula is a 500-mile long extension of the continental mainland of
Alaska, and the Aleutian Range forms its eastern backbone. Rising more than
7,000 feet above sea level the Aleutian Range marks the convergent margin of
the North American and the Pacific Plates. Recent and ongoing volcanism in the
Aleutians is the result of this subduction. Non -volcanic mountains in the Aleutian
range of the Alaska Peninsula near Naknek are comprised mainly of Jurassic
rocks, presumably formed in a similar tectonic environment in the distant past.
Granites and metamorphics are remnants of the roots of these ancient
volcanoes, and sedimentary rocks, often with plant or sea -life fossils, represent
the material eroded from these volcanoes and mountains and deposited in
lowlands and near -shore oceans. These strata have since been upthrust by the
ongoing convergence of the plates to heights of 4000 feet or more.
The Naknek region is likely underlain by Jurassic aged (approximately 144 to 206
million years old) granite and metamorphic rocks and covered by roughly 2000
feet of glacial sedimentary formations (the Pleistocene Nushagak and Pliocene
Milky River Formations.) Pyroclastic or spatter deposits of volcanic rocks of the
Meshik formation have also been found in a shallow (less than 300 feet deep)
well in the Naknek area. These rocks are approximately 28 to 48 million years
old. Marine terrace deposits and moraines and other glacial deposits from the
last ice age mantle the surface in the vicinity of Cape Suwarof.
Numerous faults have been mapped or are expected to exist in the area. The
Bruin Bay Fault cuts through Katmai National Park to the east of Naknek and can
be mapped for 330 miles from Mt. Susitna to the south shore of Becharof Lake.
Within a 300 mile radius of Naknek, 622 earthquakes above a magnitude 5 have
occurred since 1898, 124 of which were above a magnitude 6, and 17 above a
magnitude 7. The largest of these was a magnitude 8.2 earthquake which
occurred in 1938 approximately 230 miles south-southwest of Naknek. It was
one of the recent great earthquakes associated with the Aleutian subduction
zone; akin to, but smaller than, the 1964 Good Friday earthquake (magnitude
9.2).
3.2 Topography, Drainage and Vegetation
Rivers drain from the highland areas near the Aleutian Range to lakes and
eventually flow into the Naknek River in the moist tundra of the Bristol Bay
lowlands. Cape Suwarof is located in this environment at the mouth of the
Naknek River. This tundra is similar to that found in arctic Alaska due to the
maritime climatic influences at this lower latitude. Bedrock here is covered by
thick deposits of Quaternary glacial sediments. The Naknek River runs into
Kvichak Bay very near the town of Naknek. The region has a history of multiple
glaciations which at their maximum, extended nearly 100 miles west of the
NAKNEK WIND TURBINES Page 2
Geotechnicai Report
Aleutian Range across Kvichak Bay. The hydrologic cycle in the Naknek region
is influenced in part by extensive glaciers and snowfields that supply large
quantities of silty melt water to the headwaters of drainage basins during the
summer months. The region is also underlain by discontinuous or isolated
masses of permafrost.
3.3 Climatology
Naknek is located in a maritime climate, characterized by cool, humid, and windy
weather. Precipitation at the King Salmon airport averages almost 20 inches,
with 45 inches of snowfall annually. Highest amounts of precipitation are
generally in the months of July through October. Average summer temperatures
range from 42°F to 63°F; average winter temperatures range from 29°F to 44°F.
Extremes from -46°F to 88°F have been recorded.
Recent analysis of air temperature data for the King Salmon station shows that
the area is experiencing a warming trend. The following graph from the Alaska
Climate Research Center at the University of Alaska Fairbanks (2007) shows the
increase in the mean annual temperature from 1949 to 2006. In King Salmon the
trend is an increase of 4.3aF (2.4°C) or 0.08 F (.04°C) per year for the 57 year
period, See Figure 2.2.1.
40
38
36
34
32
30
28
26
King Salmon Mean Annual Temperature (OF)
5-year moving average
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Figure 2.2.1 Mean Annual Temperatures for King Salmon from 1949 to 2006, with 5-year
moving average in red and trend line in black.
NAKNEK WIND TURBINES Page 3
Geotechnical Report
4.0 FIELD INVESTIGATION
4.1 Exploration
Four borings, designated Borings B-1 through B-4, were advanced near
prearranged GPS coordinates on November 13 through the 16, 2008. Each
boring was advanced to a depth of 71.5 feet. Borehole locations are presented
on Figure 2. Drilling services were provided by Discovery Drilling of Anchorage,
Alaska using a CME 55 truck mounted drill rig. The borings were drilled with a 3-
1/4-inch inside diameter hollow stem auger. Samples were collected at surface,
2.5 feet, 5 feet, and at 5-foot intervals, thereafter. After about 50 feet in depth
some samples were collected at 10-foot intervals if soils were reasonably
homogenous. The soils were classified according to the Unified Soil
Classification System as presented in Appendix A, Figure Al. Soils were also
classified to their frost susceptibility using the system detailed in Appendix A,
Figure A2. Detailed logs of the borings and lab results are presented in
Appendix A, Figures A3 through A6.
Sampling with the split -spoon was conducted using the Standard Penetration
Test procedure. In the Standard Penetration Test, samples are recovered by
driving a 2-inch O.D. split -spoon sampler into the bottom of the advancing hole
with blows of a 140-lb automatic hammer free -falling 30 inches onto the drill rod.
The number of blows required to advance the sampler the last 12 inches of an
18-inch penetration is termed the Penetration Resistance, which was recorded
for each sample. The values give a measure of the relative density
(compactness) of the soils. The samples were sealed in heavy plastic bags to
maintain moisture content, and transported to HDL's laboratory.
At the completion of each boring, a one inch PVC pipe was installed with a cap in
order to monitor the ground temperatures. The boreholes were backfilled with
auger cuttings. Borehole locations were recorded by handheld GPS. The
locations shown in Figure 2 should be considered approximate.
5.0 LABORATORY TESTING
5.1 Laboratory Testing
Selected lab tests were performed on samples recovered from the borings to
verify field classifications and to determine the materials classification, water
content, and frost characteristics of the soils encountered.
A total of 51 water content tests were performed on samples from the borings.
The water content tests were conducted in accordance with procedures
described in ASTM D-2216. The results of the water content tests are presented
on the boring logs in Appendix A, Figures A3 through A6.
NAKNEK WIND TURBINES Page 4
Geotechnical Report
Grain size classification tests consisted of five tests performed with mechanical
sieves. The mechanical sieve tests were conducted according to procedures
described in ASTM D-422. The results of the mechanical sieves are presented
on the boring logs in Figures A3 through A6 and on the grainsize curves in
Appendix B.
Atterberg Limits (liquid and plastic limits) were determined on two soil samples.
Liquid and plastic limits were determined in accordance with test procedures
defined in ASTM D-4318. The results of these tests are summarized on the
boring logs in Appendix A and presented in Appendix B.
Salinity tests were performed on eight samples from the four borings. The
results of the salinity tests are presented in Appendix B, along with the resulting
calculated depression in freezing temperature (AT).
5.2 Instrumentation
Temporary thermistor strings were installed in the four borings. The thermistors
were allowed to equilibrate for at least three hours and data was read using a
fluke multimeter and recorded. An ice bath calibration of the thermistor strings
was used to correct temperature data. Residual calibration errors appear to be
on the order of less than half a degree Fahrenheit. The results are presented in
Appendix C.
6.0 SUBSURFACE CONDITIONS
6.1 Soils
Soils encountered consisted of silty sands and sandy silts with thin ice layers in
some locations. Three of the four borings encountered permafrost generally
below 10 feet to the depth of the borings.
Permafrost was encountered in Borings B-1 through B-3. The soils were
generally frozen below 10 feet; however, ice was encountered at four feet in
Boring B-1. Ice lenses and crystals were easily visible in Borings B-2 and B-3.
Soils were fairly homogeneous in these three borings, consisting mainly of sandy
silt or very silty sand. Fines contents ranged from 46 to 66 percent, with frost
classifications of F3 to F4, or moderately to highly frost susceptible. Gravel, or
possibly larger rock, was present in some samples below 55 feet in Boring B-2
and below 25 feet in Boring B-3. Moisture contents in these borings ranged from
about 10 to 59 percent. High moisture values were found in soils with high
organic content and/or high ice content.
Boring B-4 did not encounter frozen soils, except for a possibly frozen section
less than 5 feet thick at 35 feet in depth. Organic, sandy silt was encountered
from the surface to 25 feet in depth. These soils had moisture contents ranging
from 29 to 59 percent. Underlying these soils were sandy silts and silty sands to
NAKNEK WIND TURBINES Page 5
Geotechnical Report
55 feet below the surface. These silty soils had moisture contents from 14 to 23
percent. One sample from 25 feet was found to have 84 percent fines. This
sample was also noted as behaving plastically in the field. Frost classification of
these soils is F3 to F4, or moderately to highly frost susceptible. Gravel was also
noted in some samples from 30 to 55 feet in depth. From 55 feet to the depth of
the boring very wet, heaving, silty sands were encountered. These sands had
moisture contents ranging from 15 to 22 percent, and a sample from 55 feet had
20 percent fines. Frost classification of these sands is F3, or moderately frost
susceptible.
Temperatures recorded in the borings ranged from 280F to 35°F. The
temperatures in Borings B-1 through B-3 ranged 30.2°F to 31.9°F to the depth of
the borings. Boring B-4 experienced warmer temperatures, with a range 32°F to
34°F. Boring B-4 may have experienced warmer temperatures due to time
constraints and the temperatures may not have equilibrated in the boring,
however evidence of permafrost was not encountered in this boring.
Temperature results are presented in Appendix C. The salinity values for the
pore water ranged from 0.01 to 0.74 parts per thousand (ppt). These values
correspond to freezing point depressions from 0.01 to 0.04°F.
Atterburg plasticity results range from a plasticity index of 5 to 8, which
demonstrates that the silts may behave as a low plasticity clay or clayey silt,
especially those silts at depths of about 20 to 30 feet below the surface.
Atterburg results are presented in Appendix B.
7.0 PRELIMINARY ENGINEERING ANALYSIS &
RECOMMENDATIONS
Design of any structure's foundation must consider the bearing support
capabilities of the support soils as well as the expected settlements and effects of
seasonal frost action. The soils at each site are predominantly sandy silts and
some silty sands. Permafrost is present and discontinuous at the project site.
Temperatures within the frozen soils ranged from about 30.2°F to 31.9°F. Soil
temperatures are shown in Appendix C. Due to the frozen nature of many of the
soils and the anticipated loads of the structure, a pile foundation is recommended
to support the wind generators. The analysis and recommendations are
presented in the following sections.
7.1 Pile Analysis
Pile foundations for the wind generation towers are required to adequately
support the loads for the wind towers in the permafrost soils. The pile analysis
involved hand calculations and the use of computer models to determine pile
capacity for the permafrost conditions. Boring B-4 did not encounter permafrost.
The pile analysis was conducted using both thawed and frozen soils. The frozen
NAKNEK WIND TURBINES Page 6
Geotechnical Report
condition for the soils encountered was found to give the conservative result in
the analysis.
Axial Capacity
Three pile sizes were evaluated in the initial design process; 24, 30, and 36-inch
diameter. The piles were analyzed without helices. The addition of helices to the
piles will increase the allowable axial load. Axial capacities were determined for
a driven condition and are presented in Figure 3.
The allowable capacity includes a factor of safety of 3.0 due to the warm
permafrost conditions. Capacities were based on an allowable settlement or
creep rate of 1.5 inches in 30 years. Capacity analysis considered both creep
rate of the pile in permafrost and the adfreeze bond strength of the pile -
permafrost bond. The governing condition was the adfreeze bond strength of the
pile -permafrost bond.
The uplift capacity of the piles is roughly equal to the axial capacity of piles in
permafrost. This is due to the adfreeze bond between the soil and pile interface,
which reacts the same in both directions. The pile analysis completed in this
report should be reviewed when the final uplift loads are known for the piles.
The calculations to determine the capacities assumed that the active layer is 5
feet thick. The depth of permafrost was considered to be at 12 feet for the
design. The current depth to permafrost is generally 10 feet, the additional 2 feet
accounts for some deepening of the permafrost due to construction, added heat
from the pile, and long-term climate trends.
Lateral Capacity
The lateral capacity of a pile is
permafrost, stiffness of the pile,
foundation. Once a foundation is
determined.
7.2 Additional Considerations
dependent upon the soils, creep rates of the
and how fixed the head of the pile is to the
known, the lateral capacity of the pile can be
Frost Heave Forces
To minimize the frost heave forces on the piles it is recommended that a smooth
durable coating be applied. The coating should be applied to the pile embedded
in the top 5 feet of the ground plus 6 inches above final grade. We recommend
HB Fuller IF-1074 fusion bonded epoxy over 3 mils thickness (minimum) of arc -
or flame -sprayed aluminum applied per AWS C2.2 over a sandblasted near -white
metal surface to SSPC-10 standards or similar. This will limit the adhesion of the
adfreeze bond between the steel pile and the soil and reduce the uplift forces
generated by the frost action.
NAKNEK WIND TURBINES Page 7
Geotechnical Report
Pile Groups
Piles should not be installed with less than three times the pile diameter between
them in order to avoid a reduction in individual pile capacity. Piles spaced
greater than three times the pile diameter apart will behave as individual piles.
Thermosyphons
Depending upon the foundation thermosyphons may be needed to assist in
maintaining the present soil temperatures at the site through the life of the facility.
7.3 Additional Analysis
Additional analysis and review of our recommendations should be completed
when the final loading scenario is known for the foundation. Loading conditions
for wind turbines may exceed the loading conditions used for the analysis
contained in this report. Additional axial and uplift capacities, beyond those
shown in Figure 3 may be obtained with helical piers, larger diameter piles, steel
piles filled with concrete, or other types of pile configurations. In addition, the
arrangement of the piles in the foundation will change the loading that a pile will
have to support. Such analysis and capacities will need to be determined once
the final loading scenario and foundation is determined.
The actual allowable load for the individual piles should be verified in the field
from a load test performed in accordance with ASTM D-5780 "Standard Test
Method for Individual Piles in Permafrost Under Static Axial Compressive Load".
The test pile should be loaded to the ultimate capacity of the pile. The pile load
test should be conducted on a pile that was installed in an area that has
permafrost.
8.0 CLOSURE AND LIMITATIONS
The analysis, conclusions, and recommendations contained in this report are
based on site conditions as they exist in the borings and further assume that the
exploratory borings are representative of the subsurface conditions throughout
the site, that is, that the subsurface conditions everywhere are not significantly
different from those disclosed in the borings. If during construction, subsurface
conditions different from those encountered, advise us at once so we can review
these conditions and reconsider our recommendations when necessary.
If substantial time has elapsed between submission of this report and the start of
work at the site, or if conditions have changed because of natural causes or
construction operations at or adjacent to the site, we recommend that this report
be reviewed to determine the applicability of the conclusions and
recommendations considering the time lapse or changed conditions.
NAKNEK WIND TURBINES Page 8
Geotechnical Report
Unanticipated soil conditions are commonly encountered and cannot be fully
determined by merely reviewing old borings. Such unexpected conditions
frequently require additional expenditure to attain a properly constructed project.
Therefore, some contingency fund is recommended to accommodate such
potential extra costs.
Prepared by:
Hattenburg Dilley and Linnell, LLC
Trevor W. Crosby
Staff Geologist
NAKNEK WIND TURBINES
Geotechnical Report
Reviewed By:
Hattenburg Dilley and Linnell, LLC
Lorie M. Dilley, P.E.
Principal Geotechnical Engineer
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APPENDIX A
Figure Al Unified Soil Classification
Figure A2 Frost Classification
Figure A3-A6 Borelogs
UNIFIED SOIL CLASSIFICATION SYSTEM
Criteria for Assigning Group Symbols and Names
Soil Classification
Generalized
Group Descilptions
GRAVELS
GLEAN GRAVELS
GW
well -graded Gravels
GP
Poorly -graded Gravels
COARSE -GRAINED
50% or more of
coarse fraction
Less than 5% fines
GRAVELS with fines
More than 12% fines
GM
Gravel & Silt Mixtures
SOILS
More than 50%
retained on
retained on
No. 4 sieve
GC
Gravel & Clay Mixtures
No. 200 sieve
SANDS
CLEAN SANDS
SW
well -graded Sands
S p
Poorly Graded Sands
More than 50% of
Less than 5% fines
coarse fraction
passes
SANDS with FINES
SM
Sand & Silt Mixtures
No. 4 sieve
More than 12% fines
SC
Sand &Clay Mixtures
FINE-GRAINED
SOILS
50 % or more
passes the
SILTS AND CLAYS
Liquid limit
50% a or less
INORGANIC
ML
Non -plastic & Low
Plasticity Silts
CL
Low-plasficily Clays
ORGANIC
OL
Non -plastic and Law
Plastid Organic Clays
Non -plastic and Low
Plasticity Organic Silts
No, 200 sieve
CH
High -plasticity Clays
SILTS AND CLAYS
INORGANIC
MH
High plasticity Silts
Liquid limit
greater than 50%
ORGANIC
OH
High plasticity
Organic Clays
High Plasticity
Organic Silts
HIGHLY ORGANIC
SOILS
Primarily organic matter, dark in color,
and organic odor
PT
Peat
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GROUP
KIND OF SOIL
P200
TYPICAL SOILS
NFS
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0 to 6
SW, SP
GW, GP
F1
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fi to 10
GM, GW-GM, GP -GM
SW, SP, SM, SW-SM, SP-SM
Gravelly Soils
10-20
GM, GW-GM, GP -GM
F2
Sands
6-15
SW, SP, SM, SW-SM, SP-SM
F3
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Over 20
GM, GC
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SM, Sc
fine silty sands
CL, CH
Clays PI > 12
CL, CH
F4
All Silts
ML, MH
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SM
Clays, PI < 12
CL, CL-ML
Varved clays and other
CL and ML
fine-grained, banded
CL, ML, and SM;
sediments
CL, CH, and ML;
CL, CH, ML, and SM
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i HATTENBURG DILLEY 8r LINNELL LOG OF TEST HOLE
Engineering Consultants
PROJECT NUMBER :08-107
PROJECT : NEA WIND TURBINES
Station 1 Location: NAKNEK, AK Equipment —Type: CME 55
Offset: Drilling Method: Hollow -Stem Auger
Elevation: Field Crew: DISCOVERY DRILLING
m
LL
n
0
P
10
15
20
25
30
35
n
u
L
7
J
40
Sample Data
m
T C
m U
CU : 0
W Z m (n
Ground Water Data
c y
Q C
Depth in (ft.)
b v
N
a
Time
3
c
C
Dale
11113108
f-7 (AN
2
.o
Symbol
HOLE # B-1
Total Depth: 71.50 feet
Date: 1111312008 - 1111312008
Geologist: T. CROSBY, HDL Engin
SUBSURFACE MATERIAL
.
Organic SILT brown, moist to wet. Surface -snow covered, hummocky terrain
sandy SILT moist to wet, brown to gray 0.50
2
SPT
L
4
4
g
S-1 Moisture=58.8%
I.i1l)
sandy SILT brown to gray, frozen.
4
SPT
Ln
16 38
54
S-2 Moisture=28.9%0
16
SPT
1
199
36
S-3 Moisture=29.4%
SPTLn
9
13
15
28
-
S-4 Moisture=27.9%
SPT
20
50
SM
silty SAND(SM) frozen. 0.00
„
S-5 P200=46.0%, Sa=52.9%, Gr=1.1%, Moisture=21.5%
SPT
D
38
ML
sandy, clayey SILT(ML) brown to gray, frozen. 5.00
26
64
S-6 Moisturc=19.2%
19
SPT
J,
24
43
S-7 (CL-ML), Moisture=14.9%, PI=5, LL= 19
38
SPT
44
30
74
,'
S-8 Moisture=16.2%
� ❑ CME Auto Hammer ® Cathead Rape Method ® 1401b� hammer with 30 in. drop ❑ 340lb, hammer with 30 in. drop Sheet Nurnher 1 of
L
Figure A3
HMHATTENBURG DILLEY & LINNELL LOG OF TEST HOLE
Engineering Consultants
PROJECT NUMBER :08-107
PROJECT : NEA WIND TUR81NES
Station 1 Location: NAKNEK, AK Equipment_Type: CME 55
Offset: Drilling Method: Hollow -Stem Auger
Elevation: Field Crew DISCOVERY DRILLING
m
a1
LL
a
a
40
45
50
55
60
05
v
70
Sample Data
aL
T C
~ o
d N
E E E
co z m rn
Ground Water Data
o Depth in (it.)
co C
co a n Time
0 N m
�= c Date 111131oe
() 'I O
o Symbol
HOLE # B-1
Total Depth: 71.50 feet
Date: 1111312008 - 1111312008
Geologist: T. CROSBY, HDL Enginee
z D U LL rn SUBSURFACE MATERIAL
SPT
°
50
sandy, clayey SII_,T(ML) brown to gray, frozen.
S-6 Moisture=19.2% (cont.)
.
S-9 Moisture=24.2%
50
SPT
SO
S-10 Moisture=20.2%
5p
SPT
v�
S-11 Moisture=22.8%
ri
45
SPT
50
.
S-12 Moisture=15.8%
�,
47
SPT
�
50
S-13 Moisture=14.9%
BOH
Notes:
71.5
1" pvc placed in hole.
CME Auto Hammer ® Cathead Rope Method ® 144 lb. hammer with 30 in, drop ❑ 340 lb. hammer with 30 in drop
Sheet Number 2 of
Figure A3
HMtHATTENBURGDILLEY&LINNELL LOG OF TEST HOLE
Engineering Consultants
PROJECT NUMBER :08-107
PROJECT : NEA WIND TURBINES
Station / Location: NAKNI=K, AK Equipment_Type: CME 55
Offset: Drilling Method: Hollow -Stem Auger
Elevation: Field Crew: DISCOVERY DRILLING
N
m
u_
L
n
m
O
0
5
10
15
1 20
1 25
30
35
40
❑ CME Auto Hammer ® Cathead Rope Method ® 140 lb_ hammer with 30 in. drop 340 1b. hammer with 30 in.
Sample Data
m
a
T C
H �
a -0 C3
E E E
W Z m U)
Ground Water Data
CO u Depth in ft)
C •-
v N C Time
3 U y N Date 11/14/08
rn Symbol
HOLE # B-2
Total Depth: 71.50 feet
Date: 1111412008 - 11/14/2008
Geologist: T CROSBY, HDL EI
z — v LL rn SUBSURFACE MATERIAL
Surface - snow covered, hummocky topography - frozen boggy tundra. 000
sandy SILT brown, moist to wet, medium dense. Organics present 0.50
5
5P"r
U
4
3
7
S-1 Moisture=23.5%
4
SPT
6
14
20
S-2 Moisture=24.1%
SPT.
21
30
ML
sandy SILT (ML) brown to gray, frozen. 0.00
34
64
S-3 Moisture=24.I%
SPT
14
22
20
42
S-4 Moisture=35.3%
SPT
13
14
Visible ice crystals and 1" ice lenses in sampler. 20.00
�,
14
28
S-5 Moisture=52.3%
SPT
°
19
Ice crystals present 25.00
Ls
20
39
S-6 Moisture=26.9%
16
SPT
s
21
33
54
S-7 Moisture=21.1%
°0
20
Ice crystals present 35.00
SPT
Ln
25
45
S-8 Moisture=21.4%
Sheet Number 1 of
Figure A4
HMHATTENBURG DiLLEY & LINNELL LOG OF TEST HOLE
.Engineering Consultants
PROJECT NUMBER :08-107
PROJECT : NEA WIND TURBINES
Station / Location: NAKNEK, AK Equipment —Type: CME 55
Offset: Drilling Method: Hollow -Stem Auger
Elevation: Field Crew: DISCOVERY DRILLING
N
a
m
40
45
50
55
60
T 165
70
5
3
rr
J
3
Sample Data
v
7CL+ C
0
d U T
Q a o.
(n Z Into
Ground Water Data
eO N v Depth in (R.)
c
O Time
r� N
7 Cn U 0 Hate 11114108
= M L o Symbol
HOLE # B-2
Total Depth: 71.50 feet
Date: 1111412008 - 1111412008
Geologist: T. CROSBY, HDL Engineerint
SUBSURFACE MATERIAL
SPT
50
28
.°
sandy SILT(ML) brown to gray, frozen. 40.00,
24
52
S-3 Moisture=24.1 % (cont.)
7" ice lense present
,•
S-9 Moisture=29.3%
0
28
45.00
SPT
34
75
S-10 P200=66.0%, Sa=34.0°/u, Gr=0.0%, Moisture=21.6%
32
55.00
Fractured rock in sample gravel or boulder.
SPT
35
71
S-I I Moisture=13.4%
N
50
SPT
50
S-12 Moisture=16.5%
�.
30
Fractured rock in sample - gravel or boulder. 70.00
SPT
50
S-13 Moisture=14.6%
130H
Notes: 1.50
71.5
1" pvc placed in hole.
CME Auto Hammer ® Cathead Rope Method ® 140 lb. hammer with 30 in, drop ❑ 340 lb. hammer with 30 in. drop
Sheet Number 2 of
Figure A4
HMH_ATTE_NBURG DILLEY & LINNELL LOG OF TEST HOLE
Engineering Consultants
PROJECT NUMBER :08-107
PROJECT: NEA WIND TURBINES
Station I Location: NAKNEK, AK Equipment —Type: CME 55
Offset: Drilling Method: Hollow -Stem Auger
Elevation: Field Crew: DISCOVERY DRILLING
5•
10-
I5-
20
25
30
35
40
❑ CME Auto Hammer ® Cathead Rope Method ® 140 Eb. hammer with 30 in. drop ❑ 340 Ih. hammer with 30 in. drop
Sample Data
au
C c
m U as
m � o m
;la Z m f!1
Ground Water Data
o ay v Depth in (ft)
c —
O aL Time
c Date 11115/09
() N N
U) � o o Symbol
HOLE # B-3
Total Depth: 71.50 feet
Date: 1111512008 - 1111512008
Geologist: T. CROSBY, HDL Enginee
z — LL - SUBSURFACE MATERIAL
' ' ^
brown, Surface- snow covered, boggy, hummocky topography
Organic, Sandy SILTbrown, moist to wet, loose to medium dense, 1" slush/ice at top. 0,50
3
SPT
4
3
7
S-1 Moisture=319%
SPT
ev
t„
4
18
25
S-2 Moisture=27.4%
SPT
91
sandy SILT brown to gray, trace of rounded gravel, frozen - some visible ice crystals, 0.00
2
2�
S-3 Moisture=18.7%
SPT
13
15
S-4 Moisture=35.3%
SPT
l a
CL
sandy CLAY (CL) gray, frozen - ice crystals and about 1" lenses present 0.00
J
12
23
S-5 Moisture=26.3%, PI=8, LL= 24
SPT
50
ML
5.00
gravelly, sandy SILT(ML) gray to brown, frozen. 25.50
S-6 Moisture=19.5%
possible cobble or boulder.
'
50
Ice crystals present; possible cobble or boulder. 30.00
SPT
s
S-7 Moisture=14.0%
23
SPT
�,
47
49
95
S-8 Moisture=21.4%
Sheet Number 1 of 2
Figure A5
v HATTENBURG DILLEY & LINNELL LOG OF TEST HOLE
Engineering Consultants
PROJECT NUMBER :08-107
PROJECT : NEA WIND TURBINES
Station / Location: NAKNEK, AK Equipment Type: CME 55
Offset: Drilling Method: Hollow -Stem Auger
Elevation: Field Crew: DISCOVERY DRILLING
m
L
d
N
d
40
45
50
55
60
65
70
Sample Data
m
Q
7C
N N U
co j O N
U} Z in U]
Ground Water Data
y
U
Depth in (ft.)
U
C
o
N
n
Time
N
:3
e
tti
Date
11115108
Zj
V
o
0
Symbol
HOLE # B-3
Total Depth: 71.50 feet
Date: 1111512008 - 11/15/2008
Geologist: T. CROSBY, HDL Engineerin
r" SUBSURFACE MATERIAL
SPT
54'T
SPT
0
rl�
33
34
35
35
50
3
50
67
85
gravelly, sandy SILT(ML) gray to brown, frozen. 1
S-6 Moisture=19.5%0 (cont.)
1" ice lense present
S-9 Moisture=15.6%
S-10 P200=46.6%, Sa=40.2%, Gr-13.2%, Moisture-11.4%a
sandy SILTgray, Frozen - no visible ice, I1'O0
S-I I Moisture=13.2%
SPT
N
50
60.00
possible cobble or boulder.
rn
S-12 Moisture=9.8%
47
SPT
50
S43 Moisture=16.7%
BOH
1.50
Notes:
1 ' pvc placed in hole.
CME Auto Hammer ® Cathead Rope Method ® 140 lb. hammer with 30 in. drop ❑ 340 Ib. hammer with 30 in. drop
Sheet Number 2 of 2
Figure A5
HMHA17ENBURG DILLEY & LINNELL LOG OF TEST HOLE
Engineering Consultants
PROJECT NUMBER :08-107
PROJECT : NEA WIND TURBINES
Station / Location: NAKNEK, AK Equipment Type: CME 55
Offset: Drilling Method: Hollow -Stem Auger
Elevation: Field Crew: DISCOVERY DRILLING
Sample Data Ground Water Data
_
o
Depth in (ft,)
�
o
o
cmi N
--
Time
a
U
Q.
>
y
>
N
m
U,
Dafe
11I1fi108
a
Q
E
M
E
Z
3
70
E
cu
u
O)
`�
>
U w N
m O
G
Symbol
Total Depth: 71.50 feet
Date: 11/16/2006 - 1111612008
Geologist: T. CROSBY, HDL Ei
u� z U cL rn 0 SUBSURFACE MATERIAL
5
10
15
20
25
1 30
1 35
brown. Surface, snow covered, hummocky terrain 0.00
Organic, Sandy SILTmoist to wet, loose to medium dense, brown to gray 0.50
3
SPT
;
3
5
g
S-1 Moisture=59.1%
SPT
5
5
9
S-2 Moisture=57.2%
4
SPT
6
7
13
S-3 Moisture=28.7%
7
SPT
u
I ]
12
23
S-4 Moisture=52.3%
4
sp-l-
s
s
1 ;
S-5 Moisture=34.5%
SPT
7
ML
5.00
sandy, clayey SILT(ML) grayish brown, moist to wet, medium dense
J,
8
16
S-6 P200=84.2%, Sa=15.81/o, Gr=0.0%, Moisture=22.6%
SPT
'�
I
:a ' •.
gravelly, silty SANDbrown, moist to wet, dense 0.00
'
20
39
D.:
S-7 Moisture=15.2%
SPT
iG
xsandy
SI.LTgray, appears frozen.
g
34
S-8 Moisture=19.5%
i 40
c
CME Auto Hammer
Cathead Rape Method ® 140lb_ hammer with 30 in. drop ❑ 340 lb, hammer with 30 in drop
Sheet Number 9 of
Figure A6
i HA17ENBURG DILLEY 8 LINNELL LOG OF TEST HOLE
Engineering Consultants
PROJECT NUMBER :08-107
PROJECT : NEA WIND TURBINES
Station / Location: NAKNEK, AK Equipment —Type: CME 55
Offset: Drilling Method: Hollow -Stem Auger
Elevation: Field Crew: DISCOVERY DRILLING
Q1
r
d
N
Gl
40
45
50
55
60
65
u
70
Sample Data
m
7� _
r O
a� 0 U °L
CL
E E 3
rn Z m U)
Ground Water Data
0 y �y Depth in (ft.)
c
a Time
y N c
:3 �= c Date 11116108
M V co N
m o — Symbol
Vf _ 2 p
Z �
HOLE # B-4
Total Depth: 71.50 feet
Date: 1111612008 - 1111612008
Geologist: T CROSBY, HDL Engineerin;
U u- - SUBSURFACE MATERIAL
SPT
°
1
sandy SILT gray, wet, medium dense
19
29
S-9 Moisture=15.3%
o
15
iQ. ..:
5.00
gravelly, silty SANDgray, wet, dense
SPT
19
2
41
: '.p.:
S-10 Moisture=14.2%
4
SM
silty SAND(SM} gray, wet, soupy and heaving back into auger. 5.00
SPT
50
V.
S-I I P200=20.3%, Sa=75.4 a, Gr4.31/%, Moisture=21.6%
N
34
SPT
7
50
33
g3
:. •'.
S-12 Moisture=15.0%
Bott
Notes: 11.50
71.5
i" pvc placed in hole.
CMF Auto Hammer ® Cathead Rope Method ® 140 Ib. hammer with 30 in. drop ❑ 340 Ib. hammer with 30 in.
Sheet Number 2 of
Figure AB
APPENDIX B
Laboratory Results
ME
m
m
m
COBBLES
GRAVEL
SAND
SILT OR CLAY
coarse fine
coarse medium
fine
r H_A_ TTENBURG DILLEY & LINNELL
Engineering Consultants
Job: Naknek Wind Job No. 08-107
Lab Tech: Date:
Salinity Content Sample Location:: Naknek, Ak Boring No. nla
Sample Description: Sample No. nla
Boring:
B-1
B-1
B-2
B-2
Sample:
S-2
S-11
S-5
S-9
Sample Depth:
5'
50'
10,
40'
Tare:
29.49
29.67
1
29.39
28.79
Wet + Tare:
55.74
98.14
70.44
112.4
Added Water +Tare:
94.4
152.72
145.74
161.45
D + Tare:
50.21
86.34
54.13
90.56
Measured Na m :
93
32
32
32
Water Added:
38.66
54.58
75.3
49.05
% Moisture:
26.6892
20.8223
65.9256
35.357
Natural Water:
5.53
11.8
1
1
1 16.31
1 21.84
Salinity (ppt):
0.74
0.18
0.18
0.10
1
AT
0.04
0.01
0.01
0.01
Boring:
B-3
B-3
B-4
B-4
Sample:
S-4
S-13
S-7
S-10
Sample De the
15'
70'
30'
45'
Tare:
29.4
29.68
28.77
29.37
Wet + Tare:
66.51
52.54
48.66
63.63
Added Water +Tare:
119.2
122.24
121.15
121.4
D + Tare:
58.53
49.16
45.05
58.55
Measured Na m :
32
32
32
32
Water Added:
52.69
69.7
72.49
57.77
% Moisture:
27.3944
17.3511
22.1744
17.4092
Natural Water:
7.98
3.38
1
1 3.61
5.08
Salinity t :
0.24
0.69
0.67
0.40
ATI
0.01 1
0.04
0.04
0.02
Tk*- reference temperature for sea salt (57 C)
60
CL CFI
50
P
L
A
40
S
T
I
C
T 30
Y
I
N 20
D
E
X
10
m
CL-ML ML MH
0
0 20 40 60 80 100
LIQUID LIMIT
Specimen Identification
ILL
PL
PI
Fines
Classification
•
B-1 30.0
19
14
5
Low -plasticity Clay (CL-ML)
m
B-3 20.0
24
16
8
Low -plasticity Clay
r HATTENBURG DILLEY & LINNELL
L Engineering Consultants
ATTERBERG LIMITS' RESULTS
NAKNEK ELECTRIC ASSOCIATION
NEA WIND TURBINES
NAKNEK, ALASKA 08-107
APPENDIX C
Ground Temperature Data
m
0o
Q
NO
L
o L
.E E
Q? '
o
~ z
mT
p
CL
E
0
Y
41
C
Y
m
Z
LL
us
M
v
M
M
M
Q
M
Im
N
N
cN v
�I
m m m
Y\ A
i
C O N MQ Cl qT � fo �
(11) aoe}ang punojE) moles y}dap