HomeMy WebLinkAboutBradley Lake Hydroelectric Project 1985I
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BRA
086
Alaska Power Authority
LIBRARY COPY
BRADi.d RIVER •. KENAI PENINSULA. AlASKA
BRA
086
o.t.TE ISSUED TO
BL-D-123
BRADLEY LAKE
HYDROELECTRIC PROJECT
TERRESTRIAL IMPACT ASSESSMENT REPORT
Prepared by: ENTRIX, Inc.
Anchorage. Alaska
and
Stone & Webster Engineering Corpon>.tion
800 A Street
Anchorage, Alaska
PROJECT NO. 8221
BRADLEY LAKE HYDROELECTRIC PROJECT
ALASKA POWER AUTHORITY
Section
1.0
1.1
1.2
1.3
1.4
1.5
1.6
2.0
2.1
2.2
2.3
2.4
2.5
2.6
2.7
3.0
3.1
3.2
3.3
3.4
4.0
5.0
4. 1
4.2
4.3
4.4
4.5
4.6
4.7
BL-D-123
TERRESTRIAL IMPACT ASSESSMENT REPORT
TABLE OF CONTENTS
Description
INTRODUCTION
General
Project Description
Background
Objectives
Approach to Impact Analysis
Approach to Mitigation
METHODS
Study Area
Attribute Mapping
Derivation of Species Models
Digitizing
Habitat Use Analysis
Habitat Evaluation Procedures
Mitigation
RESULTS
Introduction
Baseline Conditions
Project Costruction
Project Operation
DISCUSSION
Purpose
Vegetation
Moose
Black Bear
Brown Bear
Mountain Goats
Waterfowl
LITERATURE CITED
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Page No.
1-1
1-1
1-1
1-7
1-10
1-10
1-11
2-1
2-1
2-1
2-3
2-5
2-6
2-7
2-8
3-1
3-1
3-1
3-8
3-17
4-1
4-1
4-1
4-2
4-4
4-4
4-5
4-6
5-1
PROJECT NO. 8221
BRADLEY LAKE HYDROELECTRIC PROJECT
ALASKA POWER AUTHORITY
TERRESTRIAL IMPACT ASSESSMENT REPORT
LIST OF APPENDICES
APPENDIX SUBJECT
A SPECIES MODELS
ii
BL-D-123
PROJECT NO. 8221
BRADLEY LAKE HYDROELECTRIC PROJECT
ALASKA POWER AUTHORITY
TABLE
1
2
TERRESTRIAL IMPACT ASSESSMENT REPORT
LIST OF TABLES
TITLE
HABITAT ATTRIBUTES CONSIDERED FOR EACH INDICATOR SPECIES
DESCRIPTIONS • ACREAGES, PERCENT COVER, AND CODES FOR
VEGETATIONS TYPES FOUND IN THE BRADLEY LAKE HYDROELECTRIC
PROJECT STUDY AREA
3 DENSITY AND SUITABILITY INDICES FOR MOOSE IN THE BRADLEY LAKE
PROJECT STUDY AREA
4 DENSITY AND SUITABILITY INDICES FOR BLACK BEAR IN THE BRADLEY
LAKE PROJECT STUDY AREA
5 DENSITY AND SUITABILITY INDICES FOR MOUNTAIN GOATS IN THE
BRADLEY LAKE PROJECT STUDY AREA
6 DENSITY AND SUITABILITY INDICES FOR TRUMPETER SWANS IN THE
BRADLEY LAKE PROJECT STUDY AREA
7 ACREAGE AND VEGETATION TYPES OCCUPIED BY EACH FACILITY
8 ACREAGE OF VEGETATION TYPES AFFECTED BY FACILITIES
iii
BL-D-123
PROJECT NO. 8221
BRADLEY LAKE HYDROELECTRIC PROJECT
ALASKA POWER AUTHORITY
TABLE
9
TERRESTRIAL IMPACT ASSESSMENT REPORT
LIST OF TABLES (CONT.)
TITLE
SUMMARY OF DIRECT AND INDIRECT LOSSES OF MOOSE HABITAT AND
SUBSEQUENT DISPLACEMENT OF MOOSE DUE TO PROJECT CONSTRUCTION
10 SUMMARY OF DIRECT AND INDIRECT LOSSES OF BLACK BEAR HABITAT
AND SUBSEQUENT DISPLACEMENT OF MOOSE DUE TO PROJECT
CONSTRUCTION
11 SUMMARY OF DIRECT AND INDIRECT LOSSES OF MOUNTAIN GOAT HABITAT
AND SUBSEQUENT DISPLACEMENT OF MOOSE DUE TO PROJECT
CONSTRUCTION
12 SUMMARY OF DIRECT AND INDIRECT LOSSES OF TRUMPETER SWAN
HABITAT AND SUBSEQUENT DISPLACEMENT OF MOOSE DUE TO PROJECT
CONSTRUCTION
13 INFLUENCE OF MITIGATION ON MOOSE
14 INFLUENCE OF MITIGATION ON BLACK BEARS
15 INFLUENCE OF MITIGATION ON MOUNTAIN GOATS
16 INFLUENCE OF MITIGATION ON TRUMPETER SWANS
17 DENSITY OF WATERFOWL AND SHOREBIRDS REPORTED FOR THE STUDY
AREA
iv
BL-D-123
PROJECT NO. 8221
BRADLEY LAKE HYDROELECTRIC PROJECT
ALASKA POWER AUTHORITY
TERRESTRIAL IMPACT ASSESSMENT REPORT
LIST OF TABLES (CONT.)
TABLE TITLE
18 SUMMARY OF DIRECT AND INDIRECT LOSSES OF WATERFOWL AND
SHOREBIRD HABITAT AND SUBSEQUENT DISPLACEMENT OF BIRDS DUE TO
PROJECT CONSTRUCTION.
19 INFLUENCE OF MITIGATION ON WATERFOWL.
20 INFLUENCE OF MITIGATION ON SHOREBIRDS.
v
BL-D-123
PROJECT NO. 8221
BRADLEY LAKE HYDROELECTRIC PROJECT
ALASKA POWER AUTHORITY
TERRESTRIAL IMPACT ASSESSMENT REPORT
LIST OF FIGURES
FIGURE TITLE
1 STUDY AREA MAP
2 VEGETATION MAP
3 MOOSE
4 BLACK BEARS
5 MOUNTAIN GOATS
6 TRUMPETER SWANS
7 GENERAL PROJECT SITE MAP
8 ESTIMATED LOSS OF AVAILABLE MOOSE HABITAT OVER THE LIFE OF
THE PROJECT
9 ESTIMATED DISPLACEMENT OR LOSS MOOSE HABITAT OVER THE LIFE OF
THE PROJECT
10 ESTIMATED LOSS OF AVAILABLE BLACK BEAR HABITAT OVER THE LIFE
OF THE PROJECT
11 ESTIMATED DISPLACEMENT OR LOSS OF BLACK BEAR OVER THE
LIFE OF THE PROJECT
12 ESTIMATED LOSS OF AVAILABLE MOUNTAIN GOAT HABITAT OVER
THE LIFE OF THE PROJECT
13 ESTIMATED DISPLACEMENT OR LOSS OF MOUNTAIN GOATS OVER
THE LIFE OF THE PROJECT
14 ESTIMATED LOSS OF AVAILABLE TRUMPETER SWAN HABITAT OVER
THE LIFE OF THE PROJECT
15 ESTIMATED DISPLACEMENT OR LOSS OF TRUMPETER SWANS OVER
THE LIFE OF THE PROJECT
vi
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1.0 INTRODUCTION
1.1 General
This report presents the results of the
Quantification Study conducted for the Bradley
Project. The study was originally performed for
Terrestrial Impact
Lake Hydroelectric
Stone and Webster
Engineering Corporation in support of the Project licensing effort on
behalf of the Alaska Power Authority, State of Alaska. The original
Terrestrial Impact Assessment Report (TIAR} was issued in February 1985.
This revision updates the February TIAR to include (1) Agency
Consultation requirements presented in the Alaska Power Authority
Responses to Agency Comments on the Terrestrial Impact Assessment
Report, June 1985, (2) the elimination of a dredged access channel for
barge access to the project, and (3) establishment of a brackish marsh
for waterfowl nesting.
The report provides predictions of losses, including direct and
indirect, for habitats and animals resulting from the construction and
operation of the proposed Project. These predicted losses are based on
models of habitat suitability and habitat use by animals that are
present on Project lands. Full implementation of the models allow
accurate prediction of direct and indirect losses, and changes in total
loss, as mitigative measures are applied.
The results from this study will be used by the Alaska Power Authority
and local resource agencies to establish:
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The level of project impacts;
Whether selected mitigation accurately addresses predicted
losses;
Whether further mitigative measures are required.
1.2 Project Description
The Bradley Lake Hydroelectric Project proposed by the Alaska Power
Authority is located on the Kenai Peninsula, about 105 miles south of
Anchorage, and 27 miles northeast of Homer, Alaska. Bradley Lake is
BL-D-123 1-l
located in the Kenai Mountain Range in a glacial U-shaped valley and has
a maximum depth of about 270 feet below the existing lake level of
approximately elevation 1,080.
The proposed development includes raising the existing Bradley Lake
level 100 feet to a normal maximum surface elevation 1,180, by
constructing a dam, spillway and outlet facility at the lake outlet. An
18,820 feet long, 11 feet diameter, concrete lined power tunnel will
connect the reservoir intake works with a two-45 MW unit powerhouse
located just above sea level on the northeast shore of Kachemak Bay.
The proposed powerhouse is located near sea level on the southeastern
shore of Kachemak Bay. The terrain immediately surrounding the
powerhouse site rises from the tidal flats near elevation 10 to
elevation 1,400.
A tailrace channel will be excavated downstream of the powerhouse into
the tidal flats to allow free discharge of generating flows onto the
tidal flats and into Kachemak Bay. The tailrace will be approximately
200 feet long and will be rip-rap lined.
The proposed Middle Fork Diversion is located approximately one mile
north of Bradley Lake in an adjacent drainage at elevation 2,200 on the
Middle Fork stream. The Middle Fork Diversion facilities consist of a
small dam, spillway, and two diversion lines. One line will be provided
for initial construction efforts to bypass natural streamflows and
subsequently to serve as a permanent low level outlet for downstream
releases. The other main diversion line conveys water to Marmot Creek,
a tributary to Bradley Lake. The interbasin diversion facility will be
operational from May through October.
The proposed Nuka River Diversion is located southeast of Bradley Lake
below the Nuka Glacier at about elevation 1,300. The Nuka River
Diversion consists of constructing a small dike across the Upper Nuka
River near the Nuka Pool, excavation of the outlet weir at the Nuka Pool
oulet into the Upper Bradley River, and increasing the width of the
Upper Bradley River Channel immediately downstream of the outlet. The
outlet will be a rock cut with an inlet at about elevation 1,286 and
BL-D-123 l-2
with a minimum channel width of 65 feet. The material excavated from
the outlet will be locally graded in the vicinity of the outlet to
maintain local aesthetic values. The dike and outlet excavation will
divert the Nuka Glacier flow into the Upper Bradley River and into
Bradley Lake.
The proposed transmission of power from the Bradley Lake power plant is
over two parallel, wood pole, 115 kV lines, about 20 miles long. These
lines will tap into a new transmission line scheduled to be built by
Homer Electric Association between Fritz Creek and Soldotna in 1985 -
1986.
The proposed Project requires the development of facilities for access
to and within the Project area during construction. Also, facilities
for housing of personnel and for storage of construction and operational
equipment are provided. Whenever possible, facilities required during
construction will be so located and designed that they may be used as
permanent facilities to serve the long term needs of the Project.
Facilities not needed for long term project use will be removed and the
affected grounds will be rehabilitated.
The proposed construction facilities include the development of staging
areas and camp sites; concrete batch plants; borrow and waste areas;
domestic water supply and sewage disposal and/or treatment plants;
housing for permanent plant operations personnel and construction
manager and engineering support staffs; field laboratory testing,
warehousing, and garaging structures; and the essential services to
these facilities including heating, water, sanitary disposal systems,
and electricity. The key facilities and services to be provided are
described in greater detail in the following paragraphs.
Two staging areas are planned for the Project. A small staging area
approximately 150 feet by 350 feet will be provided as part of the barge
dock development. This area is located at the terminus of the barge
dock and will serve as a temporary laydown area for off-loading
personnel, equipment, and supplies needed for project development.
BL-D-123 l-3
the outlet will be locally graded in the vicinity of the outlet to
maintain local aesthetic values. The dike and outlet excavation will
divert the Nuka Glacier flow into the Upper Bradley River and into
Bradley Lake.
The proposed transmission of power from the Bradley Lake power plant is
over two parallel, wood pole, 115 kV lines, about 20 miles long. These
lines will tap into a new transmission line scheduled to be built by
Homer Electric Association between Fritz Creek and Soldotna in 1985 -
1986.
The proposed Project requires the development of facilities for access
to and w.ithin the Project area during construction. Also, facilities
for housing of personnel and for storage of construction and operational
equipment are provided. Whenever possible, facilities required during
construction will be so located and designed that they may be used as
permanent facilities to serve the long term needs of the Project.
Facilities not needed for long term project use will be removed and the
affected grounds will be rehabilitated.
The proposed construction facilities include the development of staging
areas and camp sites; concrete batch plants; borrow and waste areas;
domestic water supply and sewage disposal and/or treatment plants;
housing for permanent plant operations personnel and construction
manager and engineering support staffs; field laboratory testing,
warehousing, and garaging structures; and the essential services to
these facilities including heating, water, sanitary disposal systems,
and electricity. The key facilities and services to be provided are
described in greater detail in the following paragraphs.
Two staging areas are planned for the Project. A small staging area
approximately 150 feet by 350 feet will be provided as part of the barge
dock development. This area is located at the terminus of the barge
dock and will serve as a temporary laydown area for off-loading
personnel, equipment, and supplies needed for project development.
BL-D-123 1-3
Following Project Construction, this location will become the permanent
staging area.
The second and main staging area for construction needs will be located
near the lower camp area. This area, which is presently sized as 600
feet by 1,000 feet, will be provided as laydown and storage space for
each of the contractors on the Project, and for the construction
manager's needs in storing of equipment and supplies. Temporary
warehousing and garaging facilities, as well as diesel electric power
facilities and fuel supplies also will be located in this area. In
addition, laboratory testing facilities may be located in this area.
The lower camp site will be located adjacent to the active floodplain of
Battle Creek, approximately 1,000 feet southeast of the main staging
area and near the propsed access road serving the upper dam site.
Unvegetated overflow channels are found throughout the east end of the
camp site. The access road and dike will be constructed prior to camp
construction with a 20 feet wide bench between the dike and the creek
bank to minimize impacts on Battle Creek. This embankment will be
armored on the creek and Kachemak Bay side. This site is planned for
development to accommodate about 240 beds. All lower camp site
facilities can be mobilized by landing craft or barge, then skidded in
or driven in by truck.
The proposed upper camp site has been located about 1.2 miles due west
of the dam near the proposed access road. The site has 4. 6 acres of
land at an average of 20 percent slope, with a nearby pond to act as a
water supply. Because of difficult early accessibility to the site, all
mobilization ~ust be by helicopter for site development and early use,
until the access road has been completed. The upper camp site is
planned for up to 210 bed capacity. At project completion, the upper
camp facilities will be removed and the area rehabilitated.
The major borrow areas are the Martin River delta area and the dam site
rock quarry. In addition, a small quarry will be located near the
access road between the lower camp and dam site. Waste areas will be
BL-D-123 1-4
located as close as possible to the work, so as to minimize their impact
and the need for access roads.
The Martin River borrow material consists of clean, well-drained gravel,
although some screening and/or washing may be required for concrete
aggregate. The total estimated quantity of borrow is about 704,000
cubic yards. A dike will be constructe.ci in the ~lartin River delta prior
to site development to avoid causing siltation to the Martin River. The
dike will be located allowing a 50 feet wide bench between the toe of
the embankment and the nearest 4ctive Martin River channel. This buffer
will prevent construction material from falling into the river. The
dike embankment will be armored with rip-rap on the Martin River side in
order to prevent soil erosion. The dike will be designed for a flood
with a recurrence interval of 50 years, based on hydraulic analyses made
during the Project final design. Subsequent to its need, the borrow
site area will be rehabilitated and developed in compliance with the
Project Mitigation Plan.
A small quarry area will be located near the access road between the
lower camp and dam site for rip-rap material. It is anticipated that
over 30,000 cubic yards will be excavated.
The permanent access facilities include the access channel and barge
basin, airstrip, and Project roads. Roads will extend from the:
o Airstrip to powerhouse
o Powerhouse to lower camp (also serving the barge basin and
staging area
o Lower camp to upper camp
o Upper camp to dam (also serving the intake gate shaft,
spillway, and construction diversion tunnel)
BL-D-123 1-5
A temporary road will also be constructed between the lower camp and the
Martin River borrow site. The road between the lower camp and Martin
River borrow site is not depicted on the maps included with the report
since it is not a permanent facility. However, the road was included in
the impact calculations for construction activities. At the conc~usion
of the construction phase of the project, the road will be removed and
the site revegetated. This will eliminate further indirect impacts
during the operation phase and will substantially reduce the direct
impacts as revegetation progresses.
Movements of heavy or bulky equipment, construction material, and parts
to the project can be accomplished economically by waterborne
transportation which will have minimum social and environmental impacts.
To accommodate the use of sea-going barges to support the project
construction, a barge dock will be required at the project site. Homer,
strategically located at the mouth of Kachemak Bay, is approximately 27
miles from the project site and would serve to refuel and provide
shelter and services to sea-going barges and tugs enroute to and from
the project site. From Homer, Kachemak Bay is characterized by "deep
water" for 15.5 miles, shallow conditions for three miles, and tidal mud
flats for the final 1.5 miles to the project site. To accommodate barge
traffic, a facility located off-shore in the tidal flat area approaching
the project is proposed. Construction of this facility may include
dredging to remove high spots in the barge access area to a depth
sufficient to allow sea-going barge and tug traffic during extended
portions of the tide cycle. Construction will also include barge
docking and off-loading facilities; and a laydown area.
A maximum of 40,000 cubic yards of material is anticipated to be dredged
for the barge docking facility. The dredged material will be
transported and disposed of in the waterfowl nesting area which is
approximately 30 acres in size.
BL-D-123 l-6
The barge docking facility proposed will have a bottom elevation of -7.0
and a top elevation of 18 project datum. It is estimated that
approximatley 100,000 cubic yards of clean fill material will be
required to construct the facility along with an additional 25,000 cubic
yards of rip-rap for slope protection.
The barge dock and staging or laydown area and dock access roads will be
constructed of well compacted, graded, granular borrow material placed
upon the tidal mud flats, north of Sheep Point. These soil pads are to
be built north of the slough oriented east to west at Sheep Point. A
100 feet long, single lane bridge will cross over the slough to connect
the barge basin facilities with the lower camp to powerhouse access
road.
An airstrip will be located adjacent to the powerhouse site to allow
fixed wing access to the project. A parking apron has been located on
the southern one-third of the landing strip. The airstrip will be 2,200
feet long by 50 feet wide, with a 175 feet wide landing area, and with
the centerline grade at elevation 16, project datum. The runway will be
gravel surfaced and will accommodate helicopters and fixed wing
aircraft. Development of the airfield will require about 275,000 cubic
yards of material for fill, surfacing, and slope protection. It is
anticipated that about 156,000 cubic yards of material will come from
the Martin River borrow area and the remaining volume from the
powerhouse and tunnel excavation. Rip-rap material will come from the
small quarry above the lower camp.
1.3 Background
The quantification of terrestrial impacts due to the construction and
operation of the Bradley Lake Hydroelectric Project is required to
develop a mitigation plan. During 1980 and 1981, an interagency study
team, comprised of personnel from Alaska Department of Fish and Game
(ADF&G), U.S. Fish and Wildlife Service (USFWS), and the Corps of
Engineers (COE), quantified Project impacts using the USFWS
BL-D-123 1-7
Habitat Evaluation Procedures (HEP) (Rappoport et al. 1981). Following
the transfer of the Project from the Corps of Engineers to the Alaska
Power Authority, changes were made in the design and location of some
Project features. Due to these changes, the results of the HEP Analysis
were no longer valid and the terrestrial impacts were reanalyzed.. The
terrestrial impacts and associated mitigation measures were described in
the Draft Mitigation Plan, January 1985 and Terrestrial Impact
Assessment Report, February 1985.
During late 1984 and early 1985, an investigation of available
terrestrial impact techniques was completed and reviewed with the
resource agencies for concurrence on the study approach. Four classes
of impact assessment techniques were evaluated by the Alaska Power
Authority and resource agencies.
Ad Hoc. These methodologies provide minimal guidance for impact
assessment beyond suggesting broad areas of possible impacts (e.g.,
impact upon flora and fauna, impacts on lakes, forests), rather
than defining specific parameters to be investigated.
Checklists. These methodologies present a list of environmental
parameters to be investigated for possible impacts; they do not
require establishing direct cause-effect links to Project
activities. They may or may not include guidelines about how
parameter data are to be measured and interpreted.
Matrices. These methodologies incorporate a list of Project
activities with a checklist of potentially impacted environmental
characteristics. The two lists are related in a matrix which
identifies cause-effect relationships between specific activities
and impacts. Matrix methodologies may either specify which actions
impact which environmental characteristics, or may simply list the
range of possible actions and characteristics in an open matrix to
be completed by the analyst.
BL-D-123 1-8
Networks. These methodologies work from a list of Project
activities to establish cause-condition-effect relationships. They
are an attempt to recognize that a series of impacts may be
triggered by a Project action. Their approaches generally define a
set of possible networks and allow the user to identify impa~ts by
selecting and tracing out the appropriate Project actions.
Each of the techniques was evaluated for its ability to quantify
impacts. Important considerations included whether models were
available for Alaskan species, and whether the technique met the intent
of the National Environmental Policy Act (NEPA). Of the four
methodologies, the network analyses were judged to be most suitable by
the resource agencies.
The network assessment techniques quantify impacts through the use of
wildlife species models. The models are comprised of a series of
equations that utilize habitat attributes to predict either habitat
quality or species abundance. Depending upon the design of the model,
changes in habitat attributes can be used to predict future habitat
quality or species abundance.
Six network analyses were evaluated by the Alaska Power Authority and
the resource agencies.
species models were not
Three were judged not to be suitable because
available for Alaska. The fourth network
technique, the Carrying Capaeity Approach, was also deemed unsuitable
since this technique requires that the study area encompass the entire
range of each indicator species. The two techniques that were selected
to quantify the Project terrestrial impacts, the Habitat Evaluation
Procedures and Habitat Use approach were judged to be suitable to
quantify impacts due to the Project.
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1.4 Objectives
The goal of this assessment was to quantify the terrestrial impacts of
the Project for the chosen indicator species. Specific objectives were
to:
o Assess the availability of habitats and the abundance of each
species prior to construction to establish baseline conditions;
o Establish the quantity and type of habitat that will be lost
due to placement of facilities;
o Quantify the decrease in potential use by wildlife of habitats
affected by noise and disturbance;
o Assess the Project impacts to wildlife, other than the
indicator species, through extrapolation of the models; and
o Predict the influence from mitigation on habitat loss
throughout the life of the Project.
1.5 Approach to Impact Analysis
Through consultation with the resource agencies, it was agreed that both
the HEP analysis and Habitat Use analysis would be conducted. Each
methodology requires that impacts be evaluated for indicator species.
An advantage in simultaneously conducting both programs is the resulting
ability to compare predicted losses in terms of habitat units (HEP), as
well as the estimated number of animals being displaced (Habitat Use).
Following additional agency consultation, it was decided that four
indicator species would be evaluated, moose, mountain goat, black bear,
and trumpeter swan. In addition, Project influences on brown bear and
other species of waterfowl were to be evaluated through extrapolation of
results from the black bear and trumpeter swan models, respectively.
BL-D-123 1-10
1.6 Approach to Mitigation
Mitigation planning is required by State and Federal regulations. In
addition, Stace and Federal mitigation policies have been establis~ed to
define the procedures that should be followed during mitigation
planning. Following are the major regulations that require the
consideration and eventual implementation of mitigative efforts.
Protection of Fish and Game (AS 16.05.870)
The Alaska State laws pertaining to the disturbance of streams important
to anadromous fish address the need to mitigate impacts on fish and game·
that may result from such action. The pertinent portion of item (c)
from Section 16.05.870 reads as follows:
If the Commissioner determines to do so, he shall, in the letter of
acknowledgement, require the person or governmental agency to
submit to him full plans and specifications of the proposed
construction or work, complete plans and specifications for the
proper protection of fish and game in connection with the
construction work, or in connection with the use, and the
approximate date the construction, work or use will begin, and
shall require the person or governmental agency to obtain written
approval from him as to the sufficiency of the plans or
specifications before the proposed construction or use is begun.
National Environmental Policy Act
The National Environmental Policy Act (NEPA) (42 USC 4321-4347) was
designed to encourage the consideration of environmental concerns in the
planning of federally controlled projects. Regulations pertaining to
the implementation of NEPA have been issued by the Council on
Environmental Quality (40 CFR 1500-1508; 43 FR 55990; corrected by 44 FR
873 Title 40, Chapter V, Part 1500). Items (e) and (f) under Section
1500.2 (Policy) of these regulations describe the responsibilities of
federal agencies in regard to mitigation.
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Federal agencies shall to the fullest extent possible:
(e) Use the NEPA process to identify and assess the reasonable
alternatives to proposed actions that will avoid or minimize
adverse effects of these actions upon the quality of the human
environment.
(f) Use of practicable means, consistent with the requirements of
the Act and other essential considerations of national policy,
to restore and enhance the quality of the human environment
and avoid or minimize and possible adverse effects of their
actions upon the quality of the human environment.
Federal Energy Regulatory Commission
Federal Energy Regulatory Commission (FERC) regulations also refer
directly to the need for mitigation actions on the part of the
developers of hydroelectric projects (18 CFR Part 4). The following
reference is quoted from Section 4.41 of the Notice of Final Rulemaking
as it appears in the November 13, 1981, issue of the Federal Register
(46 FR 55926-55963) and adopted. Exhibit E of the proposed FERC
regulations should include, among other information,
••• a description of any measures or facilities recommended by State
or federal agencies for the mitigation of impacts on fish,
wildlife, and botanical resources, or for the protection or
enhancement of these resources •.•
The regulations go on to require details concerning mitigation including
a description of measures and facilities, schedule, costs, and funding
sources.
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Environmental Protection Agency
The Environmental Protection Agency Mitigation Policy is established
with the following major authorities:
A. Clean Water Act (33 U.S.C. §1251 et seq.)
1. Section 1251: "The objective of this chapter is to restore and
maintain the chemical, physical and biological integrity of
the Nation's waters. In order to achieve this objective, it
is hereby declared that, consistent with the provisions of
this chapter •••
(1) It is the national goal that the discharge of pollutants
into the navigable waters be eliminated by 1985 ••.• "
B. The §404(b)(1) Guidelines (40 CFR Part 230) developed pursuant to
§1344(b)(l) of the Clean Water Act.
1. 40 CFR §230.1 (c): "Fundamental to these Guidelines is the
precept that dredged or fill material should not be discharged
into the aquatic ecosystem, unless it can be demonstrated that
such a discharge will not have an acceptable adverse impact
either individually or in combination with known and/or
probable impacts of other activities affecting the ecosystems
of concern."
2.
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40 CFR §230.10(a): " . no
material shall be permitted
discharge o:f dredged or fill
if there is a practicable
alternative to the proposed discharge which would have less
adverse impact on the aquatic ecosystem ••• "
1-13
3. 40 CFR §230.10 (b): "No discharge of dredged or fill material
4.
5.
shall be. permitted if it. • causes or contributes. .to
violations of any applicable state water quality standard;
••• violates any applicable toxic effluent standards.
Jeopardizes the continued existence of species list,ed as
endangered or threatened, or results in likelihood of the
destruction or adverse modification of a habitat which is
determined. to be critical habitat.
40 CFR §230.10(c): ". • no discharge of dredged or fill
material shall be permitted which will cause or contribute to
significant degradation of the waters of the United States."
40 CFR §230.10(d): ". • no discharge of dredged or fill
material shall be permitted unless appropriate and practicable
steps have been taken which will minimize potential adverse
impacts of the discharge on the aquatic ecosystem ••• "
C. The National Environmental Policy Act (42 U.S.C. §4321 et seq.)
states, in part, "The Congress authorizes and directs that, to the
fullest extent possible all agencies of the Federal
Government shall • . • Identify and develop methods and procedures
• • • which will ensure that presently unquantified environmental
amenities and values may be given appropriate consideration in
decision-making along with economic and technical considerations
"
D. Environmental Protection Agency Statement of Policy on Protection
of Nation's Wetlands (38 FR 10834; March 10, 1973):
BL-D-123 1-14
"Policy (b) It shall be the Agency's policy to minimize
alterations in the quantity or quality of the natural flow of
water that nourishes wetlands and to protect wetlands from
adverse dredging or filling practices, solid waste management
practices, siltation or the addition of pesticides, salts, or
toxic materials arising, and to prevent violation of
applicable water quality standards from such environmental
insults."
Fish and Wildlife Coordination Act (915 USC 661-667)
Item (a) of Section 662 of the Fish and Wildlife Coordination Act (FWCA)
describes the role of the federal agencies in reviewing federally
licensed water projects:
••• such department or agency first shall consult with the United
States Fish and Wildlife Service, Department of the Interior, and
with the head of the agency exercising administration over the
wildlife resourc~s of the particular State wherein the impoundment,
diversion, or other control facility is to be constructed, with a
view to conservation of wildlife resources by preventing loss of
and damage to such resources as well as providing for the
development and improvement thereof in connection with such
water-resource development. FERC will comply with the consultation
provisions of the FWCA.
The conceptual mitigative measures outlined in this assessment have been
developed in accordance with the sequence of steps defined by 40 CFR
1508.20, pursuant to the National Environmental Policy Act (42 USC 4321
et seq.)
The mitigation planning sequence includes, in priority order of
implementation, the following steps:
o Avoid impacts through changes in design of features or
scheduling to eliminate loss of resources;
o Minimize impacts by limiting the degree or magnitude of the
action or its implementation;
BL-D-123 1-15
o Rectify the impact by repairing, rehabilitating, or restoring
the affected environment;
o Reduce the impact over time through monitoring, maintenance,
and proper training of project personnel; and
o Compensate for impacts by conduc.ting habitat construction
activities that rehabilitate altered habitats.
This sequential strategy for mitigation option analysis and
implementation is shared by both mitigation policies applied to the
Project.
The first type of mitigation measure was Project-specific and emphasized
the avoidance, minimization, rectification, or reduction of adverse
impacts, as ranked by the Fish and Wildlife Mitigation Policy and
coordinating agencies (ADF&G 1982, USFWS 1981). These measures were
implemented to keep adverse impacts to the minimum consistent with
Project requirements. They involved adjusting or adding Project
features during conceptual design and planning so that mitigation became
a built-in component of Project actions. Additional mitigative measures
will be incorporated during the final design phase of the Project and
therefore are not quantified in this report.
Several of the mitigative measures used to offset Project impacts will
include revegetation. The time required for revegetation will depend
upon the type of disturbance at the site, the species that are used, and
the site specific conditions (i.e., depth of organic layer, soil
moisture, nutrients). In general, sites will be reestablished as shrub
communities. In areas where significant disturbance has occurred to the
organic layer and root zones, more than 10 years may be required to
establish a viable shrub community. Less disturbed areas will likely
revegetate to an early seral stage in less than 10 years. The
concept:ual Project designs and the. Mitigation Plan have established a
goal of 10 years to revegetate all disturbed sites.
BL-D-123 1-16
The Alaska Power Authority, in consultation with the resource agencies,
will prepare a revegetation and rehabilitation plan (RRP) for those
areas affected by the project construction activity. In order to attain
the desired timing of vegetation recovery, area specific goals will be
established in the RRP. The area specific goals will be based upon the
desired vegetation and sera! stage as identified in the Terrestrial
Impact Assessment Report and during resource agency consultation. The
RRP will state vegetation species composition and propagation method.
Preliminary revegetation and rehabilitation plans presented in the
Interim Final Mitigation Plan (IFMP) and the Terrestrial Impact
Assessment Report (TIAR) are based upon discussions of preferred species
composition and estimate on the timing of recovery.
Investigations of vegetation recovery rates have been conducted in the
Susitna drainage and on the Kenai National Wildlife Refuge. During the
Susitna project studies, it was estimated that shrub zones provided
optimal browse habitat, seven years after being hydro-axed. Burn
recovery rates on the Kenai Peninsula and in the Susitna drainage were
considerably shorter.
During the Bradley Lake project, it was assumed that most clearing will
be by cutting, not burning. In these areas, it would be conceiveable to
have optimal browse conditions within five to seven years. Revegetation
of pads and roads would progress more slowly. Depending upon the
species selected and the propagation method, 10 to 15 years may elapse
before optimal browse conditions are obtained. For the purposes of this
report, an average recovery period of 10 years was used.
The temporary Martin River access road will be rehabilitated at the end
of Project Construction. Provisions for sand, gravel and concrete
aggregate requirements during project operation will be provided from
the Martin River borrow area and access road removal. The material can
be stockpiled at the lower camp site.
required from the amount stockpiled,
designated lower camp area.
BL-D-123 1-17
Should additional material be
it can be extracted from the
til c
0
::E:-
E-
LJJ
~
0
N
2.0 METHODS
2.1 Study Area
During studies conducted by the Corps of Engineers interagency team
prior to 1982, terrestrial impacts were quantified for an area that
encompassed 54,245 acres. The boundaries of the study area were posi-
tioned so that all direct and indirect influences on habitats from
construction and operation of the Project were included. Due to the
transmission line proposed by the Alaska Power Authority, a portion of
the study area boundary had to be altered. The area considered in this
evaluation encompassed 52,722 acres.
The study area boundary is not coincident with the formal Project
boundary. Instead, the-study area is defined to include all major
impact zones and a half mile wide buffer around the outer edge of these
zones (Figure 1).
2.2 Attribute Mapping
The physical and biological attributes of the study area were mapped by
the Corps of Engineers interagency team in 1980 and 1981. These attri-
butes included vegetation types, snow depth, location of waterbodies,
elevation, and slope. Maps were compiled from information obtained
through ground-level inspection of 87 sample sites during summer 1980
and through the evaluation of existing sources of information (Rappoport
et al. 1981).
Within each sample site, an initial point was selected by walking a
random number of minutes along a random compass heading from a feasible
access area. From this initial point, a 100-foot transect was extended
in a randomly determined direction. The transect length was increased
to 200 feet in the freshwater and saltwater herbaceous sedge-grass
habitats to increase the reliability of the sample data.
BL-D-123 2-1
Five 1.6 x 3.3-foot plots were systematically located at 25-foot in-
tervals along the random transects (nine plots in freshwater and
saltwater herbaceous sedge-grass types). Where a majority of the
transect included more than one vegetation type, the transect was
relocated 90° or 270° to ensure that each sample site was of one.vege-
tation type. The occurrence of vegetation "mosaics", where two or more
vegetation types are closely interspersed, was accounted for in the type
mapping and later data summations.
Site sampling involved the measl!rement of several features of the
vegetation. Within each plot the percent ground cover of herbs and
woody plants less than 1.5 feet was visually estimated. Shrub and tree
canopy intercepts greater than 1. 5 feet in height were measured along
the 100-foot transect to establish percent cover values in the tall
shrub and forest sample sites. Tree-related parameters, such as height,
diameter at breast height (DBH) , and species, were measured by the
point-centered quadrant method (Cottam and Curtis 1956). In measuring
"plotless" parameters (e.g. the interspersion of tall shrubs and vege-
tation less than one foot), the entire area visible throughout the
sample site was considered. Upon completion of plot~ transect, and
plotless measurements, a list was made of all vegetation species at the
site and the aerial cover of each species was estimated by Daubenmire's
cover classes (0-5 percent, 6-25 percent, 26-50 percent, 51-75 percent,
76-100 percent) (Daubenmire 1974).
The final information collected at each sampling location was a site
description. This description included topography, soil drainage,
interspersion, dominant overstory, dominant understory, ground cover,
and litter characteristics, as well as unusual features which might not
be evident from the established habitat parameters. Vegetation types
followed Viereck and Dyrness (1980) and are classified to Level III.
Habitat information that could not be adequately assessed during the
ground surveys was extracted from topographic maps, aerial photographs,
and historical records. The location of waterbodies and stream courses
were initially established from USGS topographic maps and were updated
BL-D-123 2-2
through examination of 1979 aerial photographs. Slope, aspect, and
elevation were also calculated from USGS topographic maps and were
updated, based upon the topographic maps produced by the Alaska Power
Authority. Snow depth was established from U.S. Soil Conservation
Service precipitation records from gauges located at Bradley Lake and
the city of Homer. Data from the Homer gauge was exr;rapclated to
comparable elevations and vegetation types in portions of the adjacent
study area.
Additional habitat information was required for the transmission line
corridor since the Corps of Engineers interagency team had not mapped
the current alignment. Vegetation was mapped from 1979, true color and
recent infrared aerial photography, and was ground verified during
September 1984. Information on slope, aspect, and s~ow depth was
calculated from the same sources used by the Corps of Engineers inter-
agency team to map the remainder of the study area.
2.3 Derivation of Species Models
During the development of the Habitat Evaluation Procedures, the U.S.
Fish & Wildlife Service (USFWS) produced a series of species habitat
models. Each model rates the value of specific habitat attributes
(e.g., snow depth, vegetation types) according to the importance of that
item to the species. The lists of habitat attributes for the USFWS
habitat models are presented in USFWS (1980a) and Rappoport et al.
(1981).
The initial task in preparing the species models for this study involved
a detailed review of the USFWS habitat attribute lists for the four
indicator species. The applicability of each attribute was assessed for
its relevance to the species on a regional basis and for its relevance
to the Bradley Lake study area. In addition, current literature was
reviewed and discussions were held with experts on each species. The
results of this review were that several habitat attributes for each
species model were deleted and new attributes were added. The list of
habitat attributes considered for each model is presented in Table 1.
BL-D-123 2-3
Based upon the lists compiled through the review process, the habitat
attribute maps were revised to reflect the units of measurement and
vegetative classification specifically needed to describe habitat
parameters for the indica tor species. For example, vegetation types
were grouped differently to describe individual food preferences of
moose and black bear.
The next task in deriving the models was to prepare a series of maps
depicting the relative abundance of each indicator species within the
study area. Distribution and abundance information for each species
...
were taken from the reports describing the Corps of Engineers interagen-
cy team studies conducted in 1980 and 1981 (USFWS 1982; Rappoport et al.
1981; Holdermann 1983; Krasnow and Halpin 1981). This information was
supplemented by ob-servations conducted by the Alaska Power Authority
(WCC 1983, 1984).
The actual derivation of the model involved the mathematical comparison
of the habitat attribute values with the relative abundance of each
species. This process was conducted by examining 350 points within the
study area. At each point, the relative species abundance, and habitat
value for each attribute were read from the maps. These values were
then entered in tabular from on standardized data sheets. A step-wise,
discriminant function analysis was then conducted on the values, using
the relative abundance of each species as the dependent variable and the
habitat attribute values as the independent variables. The final output
from this analysis was a regression equation that described how the
habitat attribute variables should be mathematically combined to de-
scribe the relative abundance of the species. The analysis also listed
each habitat attribute and rated the attribute as to whether it made a
significant contribution to the model. the equations and habitat
attributes that were found to be significant for each indicator species
are presented in Appendix A.
BL-D-123 2-4
The final task in deriving the models was to review how well the model
predicts the distribution of animals and birds within the study area. A
Chi-square Goodness of Fit test was initially used to establish whether
the model accurately predicted species distribution and abundance. In
addition, a linear correlation coefficient was calculated between
observed and predicted species distribution. Finally, a visual compari-
son was made to establish whether significant deviation between observed
and predicted distributions could be rationally explained. When the
models failed any one of the three tests, a full reevaluation of the
model was conducted, variables were changed or added, and the model
derivation process was repeated. This testing process was repeated
until the models accurately predicted the distribution and abundance of
each species. The models were then presented to the source agencies to
receive concurrence on the accuracy of the models and the practicality
of using the models to predict Project impacts and influences of mitiga-
tion.
2.4 Digitizing
After the models were finalized, a series of maps were produced that
depicted the modeled density of each indicator species for each habitat
type within the study area. These maps and the vegetation map were
digitized using a Geographic Information System computer program. The
computer then calculated the area of each habitat type, multiplied the
area by the density of animals and produced a map that depicted the
expected number of animals in each section of the study area.
In addition to the species maps, a map depicting Project facilities, and
a map depicting noise produced by construction and operation activities
were produced and digitized.
The digitizing equipment used for this study allowed for a minimum
recognizable distance of 0.0003 map inches or approximately eight inches
on the ground. This level of accuracy allows precise calculation of
areas occupied by facilities.
BL-D-123 2-5
2.5 Habitat Use Analysis
The Habitat Use Analysis assessed impacts by comparing the number of
animals that could potentially occur in an area "with" and "without" the
influences of the Project. A minimum of three points in time were
needed to assess the "with Project" scenario: conditions prior to
construction; conditions during the construction period; and conditions
at the conclusion of the life of the Project. Intermediate points were
added if it was assumed that a significant change in conditions was to
occur in Project features, habitats, or in a mitigative feature. For
the Bradley Lake impact assessment, six points in time were selected:
1. Year 0 -No Project Activities occurring;
2. Year 4 Point of maximum habitat loss or alteration due
to construction of facilities and associated
noise;
3. Year 6 -Conclusion of all indirect influences including
helicopter traffic, heavy road traffic, and
blasting;
4. Year 17 -Mitigative measures reach maximum habitat value;
and
5. Year 50 -Conclusion of the life of the Project.
The predicted impacts were calculated based upon the difference in the
anticipated abundance of animals in the area with and without the
Project. To predict the future abundance of animals in the study area,
it was necessary to predict the future habitat attribute values.
Several assumptions were made in predicting future habitat conditions
including:
BL-D-123 2-6
0
0
0
0
All physical habitat attributes, including slope, aspect,
elevation, snow depth, ice cover, location of waterbodies, and
stream courses will remain unchanged.
Vegetative succession will continue at the same rate over the
next 30 years as it has for the past 30 years.
No natural or man-made disasters will occur, including large
scale forest fires or oil spills.
No additional human development of the study area will occur.
These assumptions were reviewed with the resource agencies and concur-
rence was obtained prior to initiating the impact assessment.
2.6 Habitat Evaluation Procedures
The Habitat Evaluation Procedures can be used to document the quality
and quantity of available habitat for selected wildlife species. HEP
provides information for two general types of wildlife habitat compari-
sons, the relative value of different areas at the same point in time,
and the relative value of the same area at different points in time. By
combining the two comparisons, HEP can quantify the impact of changes to
wildlife habitats. Knowledge of existing and anticipated habitat
characteristics, in conjunction with proposed Project plans, can then be
used to recommend measures for mitigating those impacts.
Baseline conditions and expected changes are described in terms of
Habitat Units (HU's). The number of HU"s is defined as the product of
the Habitat Suitability Index (HSI), i.e. quality, and the total area of
available habitat, i.e. quantity. The theory and methodology behind HSI
values is detailed in USFWS (1980 a, b, c, d).
The basic criteria for the development of HSI values is that they range
from 0 to 1 and that they are proportionately accurate (i.e., that an
HSI of 0.4 is twice as important as an HSI of 0.2). For his study, HSI
BL-D-123 2-7
values were based upon the density of animals that are predicted to
occur in each habitat.
Therefore, for each set of unique habitat characteristics, the species
model estimated the suitability of that area for use by a particular
bird or mammal. The value of that habitat was then multiplied by the
acreage occupied by that habitat to obtain the number of habitat units.
This procedure was repeated for each habitat in the study area. Final-
ly, the habitat units for each vegetation type were summed to indicate
the total number of habitat units for each species in the study area.
These calculations were repeated for the six time intervals used in the
Habitat Use Analysis, for the "with" and "without" Project scenarios.
The difference in habitat units between the "with" and "without" Project
scenarios is then described as the impact of the Project on each spe-
cies.
2.7 Mitigation
During the development of the Project Federal Energy Regulatory Commis-
sion license and subsequent licensing support, specific mitigative
measures were incorporated in the Project plan. These measures includ-
ed:
o Rehabilitation of the Martin River borrow site.
o Rehabilitation of the dredge disposal site.
o Revegetation of the lower camp.
o Revegetation of the upper camp, the road to the Martin River
delta, and the lower quarry site.
o Allowing the transmission line corridor to revegetate to an
early seral stage.
These mitigative measures will be initiated during the construction
phase of the Project and will attain their maximum value to wildlife
during the first 10 years of Project operations. The habitats will then
BL-D-123 2-8
be maintained at or near the optimal stage throughout the life of the
Project. The influence of instituting these measures was quantified for
each indicator species using the models derived for this study.
BL-D-123 2-9
3.0 RESULTS
3.1 Introduction
As stated, the formal impact quantification process, as developed for
the Habitat Evaluation Procedures (HEP) and Habitat Use procedures,
allows for the separation of impacts between short-term and long-term
effects. This provides the Alaska Power Authority and local resource
agencies with the ability to design m~tigative measures that specifical-
ly address each type of impact.
Following a discussion of baseline conditions (Section 3.2), the impact
quantifications are presented in discussions that focus separately on
construction (Section 3.3) and operation (Section 3.4) phases of the
Project. The influences of the mitigative measures included in the
conceptual Project designs are presented in Section 3.4. The impacts of
the Project on brown bear and other species of waterfowl are presented
in Chapter 4.0 since these discussions are based on extrapolation of the
models derived for other species.
3.2 Baseline Conditions
The abundance and distribution of vegetation and wildlife was assessed
by the Corps of Engineers interagency team during 1980 and 1981. This
information was supplemented by data collected by the Alaska Power
Authority in 1983 and 1984. The combined data sets were used to quanti-
fy the baseline conditions.
3.2.1 Vegetation
During the investigation of vegetative communities, 114 plant species
were identified. No species were found that are currently listed or
that are being reviewed for inclusion on the threatened or endangered
plant list. Fifty-six types, both vegetated and unvegetated, were
mapped.
BL-D-123 3-1
The two most common vegetated types were sedge-grass communities and
closed coniferous forest communities, occupying 16.6 and 16.9 percent of
the study area, respectively (Table 2). The least abundant types were
closed deciduous forests (0.2 percent) and mixed deciduous conifer
forests (0.8 percent).
Vegetation diversity varied for different sections of the study area.
Vegetation in the Fox River Valley was principally composed of a mosaic
of woodlands, shrub thickets, and sedge-grass meadows (Figure 2). In
the upper Fox River Valley, conifer forest was the predominant type,
with balsam poplar groves and alder thickets abundant in the middle
portions of the valley, and freshwater and saltwater marshes dominant in
the lower valley.
The forest on the east slope of the Fox River Valley was composed of
closed spruce forest that extended from 150 ft to 1500 ft elevation.
The tree canopy cover was 60-75 percent, and the shrub understory was
alder, rusty menziesia, and devil' s club. The slopes were less than
45°, and the organic layer was moderately well-drained.
A gradually-sloping bench ranging from 1250 ft to 2500 ft elevation
occurred above the spruce zone. Vegetation on this bench consisted of
tall alder on the lower slopes and shrub tundra at the higher ele-
vations.
Vegetation on the north-facing slopes above Bradley Lake was composed of
alder stands that graded into shrub tundra at the higher elevations.
The south-facing slope of Bradley Lake was similar, but the lower
elevations has a low shrub understory. Low willows occurred in the
shrub tundra at higher elevations north of the lake. The vegetation
north and south of the Bradley River Canyon was a mosaic of tall alder,
mesic herbaceous sedge-grass, shrub tundra, and open coniferous forest.
The lower portion of the Kachemak Creek Valley and its tributary (ele-
vation 1100-1300 ft.) contained nine shrub and herbaceous vegetation
types. Vegetation in this area was composed of low willow mixed with
BL-D-123 3-2
mesic, herbaceous sedge-grass. The lower valley was partially divided
by a knoll with mesic, herbaceous sedge-grass/tall alder on the
south-facing slope, and mesic, herbaceous sedge-grass/tall alder/tall
willow on the north-facing slope (elevation 1200-2000 ft.).
The Martin River delta was comprised of a sparsely-vegetated floodplain
with stands of open balsam poplar and mixed, balsam poplar and spruce
trees. Tall willow and alder occur in the understory as shrub thickets.
Forests on the slopes adjacent to the floodplain were primarily
vegetated by closed coniferous forests.
That portion of the transmission line corridor located west of the Fox
River valley was principally vegetated by open and closed coniferous
forests. Shrub habitats, bogs and sedge-grass meadows were also
present.
3.2.2 Moose
During the period October 1983 to June 1984, the seasonal distribution
of moose in the study area was monitored. The data that was collected
on moose movements was presented in the Moose Survey Report prepared by
Woodward-Clyde Consultants (1984). The number of moose observed in the
area ranged from a low of 8 moose on June 7 to a high of 110 moose on
December 13. The total number of moose observed in the area remained
relatively constant between October 12 and November 14, ranging from 11
to 39 moose. Beginning on November 19, the number of moose began
increasing during each survey and reached a high count of 110 moose on
December 13. Through the following two weeks, the number observed
declined to 61 moose. During February and March, the number observed
was within the range that had been observed during October (18 to 25).
On April 25, the number of moose observed increased to 44 animals. On
June 7, the lowest count for the survey period occurred (8 moose).
In general, the total number of moose observed in the study area was
directly related to the number of moose counted in the Fox River valley.
BL-D-123 3-3
It was noted that Clearwater Slough and Sheep Creek were heavily
utilized by moose during the rut, during winter, and in the spring. The
2 density of moose in the Fox River valley averaged 1. 3 moose/mi and
2 ranged from 0.04 to 3.78 moose/mi •
The influx of moose into the Fox River valley between November 14 and
December 13 did not result in a corresponding decrease in the number of
moose observed in other portions of the study area. Bailey et al.
(1976) related the increase of moose in the Fox River valley to movement
of animals from the Caribou and Boxcar Hills areas. Ballard et al.
(1982) noted that moose populations are often comprised of resident and
migratory individuals. Therefore, it is likely that a large proportion
of the moose that occurred in the Fox River valley in late November and
early December were migrants from outside the study area and that the
moose within the area do not comprise a distinct population but instead
are a subgroup of a larger population.
Observations of movements within the study area were also recorded
during the surveys. This information included observations of tracks
and sightings of unique groups or individuals. During the surveys it
was apparent that moose were moving between the Fox River valley and the
Caribou and Boxcar Hills areas. On February 28, tracks were observed
leading from Clearwater Slough, northwest to the Boxcar Hills area. In
addition, tracks and observations of unique groups and individuals
indicated that movement does occur between the Fox River valley and
Kachemak Creek. Observations included the presence of tracks and unique
individuals. Specifically, on November 19, 1984, a bull was observed in
Kachemak Creek valley that was missing the left antler. On November 26,
1984, no bulls were observed in Kachemak Creek valley and a bull missing
the left antler was observed on the bench area above Bradley River.
During the December 3, 1984 survey, no moose were observed on the bench
and bulls were not observed in Kachemak Creek; however, a bull missing
the left antler was observed on the south side of Clearwater Slough.
These observations of animals were supplemented by scattered
observations of tracks between Kachemak Creek and the Fox River valley.
The route that was observed led from the northwest portion of Kachemak
BL-D-123 3-4
flats, along the northern edge of the lake, then across the bench, and
into the Fox River valley. During the survey period, there was no
evidence that moose moved from Kachemak flats to the Nuka River valley.
Based upon these survey results, and the additional survey data obtained
by the Alaska Department of Fish & Game (ADF&G) (Holdermann 1983) and
the Corps of Engineers interagency team (USFWS 1982), it was concluded
that three sections of the study area support resident moose, and two
sections of the area seasonally support migratory moose. The three
resident groups occur in the Fox River valley (18 to 25 moose), Kachemak
Creek flats (4 to 13 moose), and the Nuka River valley (4 to 11 moose).
The migratory moose occur in the Fox River valley and the area adjacent
to Caribou Lake and the Boxcar Hills (at least 70 moose), and in the
bench north of Bradley Lake (0 to 12 moose observed). Within the entire
study area, a maximum of 110 moose were observed.
The model derived for this study predicts the distribution and abundance
of moose within the study area using a combination of physical and
biological attributes (Figure 3). The model predicted that the study
area could support 106.5 moose. Moose distribution, as predicted by the
model accurately estimates the observed distribution of moose. Using
the density of moose to calculate the Habitat Suitability Indices, the
study area consists of 32,264.2 habitat units (Table 3).
3.2.3 Black Bear
Evidence of black bears has been found in most sections of the st:uciy
area. During the Corps of Engineers interagency studies, Rappoport et
al. (1981) considered black bears to be a commonly occurring species.
During summer 1980, the Corps of Engineers interagency team recorded the
cumulative number of black bear sightings in most sections of the study
area. Observations of bear were made in the transmission line corridor
during fall 1984 by the Alaska Power Authority.
BL-D-123 3-5
Through these investigations, a total of 32 black bear sightings were
made. The largest percentage of observations were made along the
transmission line corridor, in the Fox River valley, and along the sedge
flats between the Bradley and Martin Rivers. Based upon this
information as well as additional ADF&G Surveys, it is estimated that
between three and six bears occur along the transmission line corridor,
eight to twelve bears occur between the Fox River valley and the Martin
River, and seven to ten bears are present in the shrub habitats at the
higher elevations.
Bear abundance in the study area can also be approximated from home
2 range sizes. Females with cubs have the smallest home ranges (3.5 mi );
however, home range size usually increases after the cubs become
2 yearlings (10 mi ). Adult males have the largest home ranges, averaging
2 52 mi (Schwartz and Franzman 1980).
The model derived to predict the abundance and distribution of black
bear estimated that 24.0 bears occur in the study area (Figure 4). This
predicted abundance is within the range of bears observed and the number
predicted based upon home range size. Using predicted bear density to
calculate Habitat Suitability Indices, the study area consists of
27,869.7 habitat units (Table 4).
3.2.4 Mountain Goat
Within the study area, mountain goats are widely dispersed during the
summer, but concentrate on a smaller range during winter. Goats
reportedly move to summer range in late May or early June and return to
winter range in late October to early November.
BL-D-123 3-6
Winter surveys conducted by ADF&G within the study area from 1979 to
1982 have shown that mountain goats were concentrated in the vicinity of
the Bradley River, within a 2.5 mile radius of the Bradley Lake outlet
(Holdermann 1983). The largest number of goats observed was 27 in late
March 1980 in the Bradley River Canyon. Of these animals 19 wer;e 1.5
miles from the lake outlet and 1. 5 miles east of the Bradley River,
eight goats were on the west side of the river near the lake outlet.
Goats move from one side of the Bradley River Canyon to the other on a
trail and shallow crossing at the lake outlet (Holdermann 1983).
The summer range of mountain goats in the Bradley Lake area encompasses
the area from Sheep Creek, through the mountains around Bradley Lake to
the Nuka Glacier. During summer surveys conducted by ADF&G from 1979 to
1981, goats occurred in groups ranging from 1 to 17 animals (Holdermann
1983).
The model which predicts mountain goat abundance and distribution
estimated that 36.6 goats occur in the study area (Figure 5). The same
model adjusted to habitat suitability predicted that 5,238.4 habitat
units occur in the study area (Table 5).
3.2.5 Trumpeter Swan
Trumpeter swans are common in the study area during the spring and fall
migrations, and are occasionally present during other seasons, including
winter. During the spring, swans are most frequently observed in the
wetlands adjacent to the Bradley River-Sheep Creek estuary. The number
of swans observed and the timing of their occurrence suggest that their
use of the study area is primarily for feeding during migration.
Nesting has been confirmed on only one occasion on a lake near
Clearwater Slough. During spring most swans have been observed at Goose
Point near the confluence of the Bradley River and Sheep Creek.
Significantly fewer birds have been observed near Fox Farm Creek.
BL-D-123 3-7
During mid-August, swans begin to stage in the Fox River valley. The
density of swans present during this season averaged 2.6 birds/mi2 .
This was similar to the density of swans found during the spring. The
distribution of swans during the fall was also similar to that observed
during the spring migration.
The model derived to predict the density and distribution of swans
estimated that 34.1 swans could occur in the area and that 8, 730.9
habitat units are present in the study area (Figure 6; Table 6).
3.3 Project Construction
The amount of habitat available to wildlife will decrease during the
construction phase of the Bradley Lake Hydroelectric Project. Habitat
availability will be affected directly through the construction of
facilities and indirectly through the effects of noise and disturbance
associated with construction. The effects associated with facility
placement (direct impacts) are quantified separately from the effects of
noise (indirect impacts) due to the extent and duration of the habitat
loss. The facilities considered in this evaluation are depicted in
Figure 7.
Indirect impacts from the project included the effects of noise and
disturbance on the indicator species. Based upon the existing project
design, it is anticipated that three types of activities will produce
noise that could disturb wildlife. These were blasting, aircraft, and
construction vehicles. Blasting will occur at the lower quarry, the
powerhouse, the Middle Fork Diversion, the dam site, the dam site
quarry, and the Nuka River Diversion. Aircraft flights will occur
between the major project facilities, and vehicle noise will occur on
the roads and staging areas.
BL-D-123 3-8
The noise levels for each of these three sources was obtained from the
current literature. Blasting noise was estimated to be 120 to 135 dB at
the source. This estimate was derived from a blasting study conducted
by Woodward-Clyde Consultants (WCC)(1982) on the Kenai National Wildlife
Refuge using 36 pound charges. Aircraft and heavy trucks and equ~pment
noise was estimated to range from 70 to 85 dB (Kerbec 1972).
Noise radiates from the source as waves, whose energy is a function of
distance from the source. Initially the wave front is spherical. When
the sound waves encounter a planar surface, such as the ground or
water-air interface, the wave is reflected so that the wave front is
approximately hemispherical. As the wave continues to expand, its
geometry approaches the configuration of a vertical, planar surface;
however, as the wave expands, its energy is dissipated.
dissipation of sound energy is referred to as attenuation.
This
The sound attenuation rate is a function of many variables, including
frequencies. Other factors that contribute to the dissipation of sound
energy are atmospheric condition, type and density of vegetation, soil
and ground condition, and topography.
Attenuation rates for the Terrestrial Impact Quantification Program were
derived from WCC (1982) and Kerbec (1972). It was estimated that
vehicle noise would attenuate to a noise level of approximately 60 to 65
dB at a distance of 600 ft from the noise source. A noise of 60 to 65
dB is equivalent to the noise of normal speech (Kerbec 1972). Within
200 ft of an aircraft, the noise level was estimated to be 70 to 75 dB
and within 600 ft, the noise would be attenuated to approximately 60 to
65 dB.
The noise from blasting is louder than other noises associated with
construction activities. for this reason, noise levels were estimated
for several distances from the source. The distance and estimated noise
levels are presented below.
BL-D-123 3-9
Distance from Source (ft) dB
0 120-135
BOO 120-135
1400 115-130
2200 105-115
2600 105-115
3300 100-110
4700 100-110
6700 90-95
For each distance interval away from the source, it was necessary to
estimate the decreased use of the areas by the indicator species.
Information on the effects of noise on wildlife were compiled from a
variety of sources. Many of these sources are presented in Chapter 11
of Exhibit E (List of Literature) of the Bradley Lake FERC License
Application. Based upon this information, a number between 0 and 1 was
assigned to each distance interval. In accordance the the HEP guide-
lines, a habitat score of zero implies no value, while a score of 1
indicates the best quality habitat available within the study area.
This number was then multiplied by the number of habitat units and
animals estimated to occur within each distance interval from the noise
source. The resulting numbers represented the estimated number of
habitat units and animals that would occur in the area while the noise
was present. Since no information is available on blasting, aircraft,
or vehicle schedules during the construction period, it was assumed that
these activities would occur throughout the construction phase.
The multipliers for each distance interval are presented below:
BL-D-123 3-10
Noise Type Distance from Source (ft) Multiplier
Blasting 0-800 0
800-1400 0.1
1400-2200 0.2
2200-2600 0.3
2600-3300 0.3
3300-4700 0.4
4700-6700 0.5
Aircraft 0-200 0.3
200-600 0.5
Vehicles 0-600 0.5
3.3.1 Vegetation
During the construction period, the principal effects on vegetation will
be the direct loss of habitat through facility placement. In total,
5,224 acres will be utilized for Project facilities (Table 7); however,
this total includes the 1, 568 acres occupied by Bradley Lake. In
addition, 304.2 acres that will be occupied by facilities are currently
comprised of small lakes and unvegetated mud flats. Therefore, 3,351.8
acres of vegetation will be directly affected by facility construction.
The greatest loss in acreage from a single facility will be due to the
inundation of shrub and sedge habitats by the reservoir. The reservoir
will affect 2,577.4 acres comprised of 12 vegetation types. The
predominant vegetation types that will be affected are low shrub/low
willow habitats (801.5 acres) and mesic herbaceous sedge-grass/tall
alder/tall willow habitats (595.8 acres). This loss will significantly
reduce the amount of these types available within the study area. Low
shrub/low willow habitats will be reduced by 56.4 percent, while mesic
herbaceous sedge-grass communities will be reduced by 43.4 percent. Of
the remaining ten vegetation types that will be affected by the
reservoir, the availability of two types (tall alder /low shrub and
freshwater herbaceous sedge) will be reduced by 20 to 30 percent. All
other types will be reduced by only 0.2 to 15 percent (Table 8).
BL-D-123 3-11
Construction of the transmission line will affect the largest number of
vegetation types. The transmission line corridor will occupy 762.4
acres and will affect 22 vegetation types. The predominant vegetation
that will be affected is closed coniferous forest. In total, 352.4
acres of this type will be cut, representing 4.0 percent of the closed
coniferous forest in the study area.
In general, the quantity of vegetation affected by facilities does not
represent a significant proportion of the amount of most types in the
study area. Of the 45 vegetation types identified in the area, 16 types
will be unaffected by facilities, and 20 types will be decreased by less
than 10 percent. The three vegetation types that will be affected the
most are low shrub/low willow, mesic herbaceous sedge-grass/tall
alder/tall willow, and closed balsam poplar forest, which will decrease
by 57.0, 43.4 and 55.6 percent respectively.
3.3.2 Moose
Moose abundance and distribution will be altered during the construction
phase of the Project. Construction of Project facilities will result in
the direct loss of 2,922.1 habitat units and the likely displacement of
approximately 10 moose. Impacts associated with the development of the
reservoir result in the majority of these losses (Table 9). Inundation
of shrub and sedge habitats at the east end of Bradley Lake will result
in the loss of 2, 224.0 habitat units and the likely displacement of
seven moose. Reservoir losses represent 76.1 percent of the total
reduction in habitat units.
The second most substantial loss will be due to the construction of the
transmission line. This facility eliminates 569.8 habitat units and
results in the displacement of approximately two moose. In combination,
the reservoir and transmission line account for 95.6 percent of the
direct habitat impacts.
BL-D-123 3-12
Indirect impacts due to blasting, aircraft flights, and vehicle noise
will also affect the abundance and distribution of moose. Based upon
the response of moose to noise and disturbance, it was estimated that
4,156.4 habitat units would be unavailable to moose due to blasting.
This equates to a displacement of approximately 14 moose (Table 9).
Aircraft disturbance will result in an additional decrease of 497.8
habitat units, and displace two moose. It is estimated that vehicle
noise will have a negligible effect, decreasing available habitat by
11.9 habitat units.
In combination, direct and indirect influences will result in a decrease
of 7,588.2 habitat units and the displacement of 25 moose. This
represents a 23.5 percent decrease in the habitat units currently
available to moose in the study area. The duration of the indirect
component of this impact is expected to be short, persisting only
through the construction period.
Based upon the results of the Terrestrial Impact Quantification Program,
it is likely that the moose will be lost from the Kachemak Creek valley.
However, at this time, data is insufficient to establish whether the
moose will remain in the lower Kachemak Creek valley and die, or whether
they will attempt to find other suitable range above and adjacent to the
reservoir rim. As indicated in other project documents, the Alaska
Power Authority proposes to monitor the movements of the moose while the
reservoir is filling to establish whether the moose are making an
attempt to leave the lower valley.
3.3.3 Black Bear
Adverse impacts to black bears due to Project construction will be
substantially less than the projected impacts on moose. Construction
activities will result in the direct loss of 1,681.1 habitat units, and
the displacement of two bears. This loss represents 6.0 percent of the
habitat units available to black bear within the study area.
BL-D-123 3-13
As with moose, the largest habitat losses result from construction of
the reservoir and transmission line. The reservoir will inundate 896.1
habitat units and will result in the partial displacement of one bear.
The transmission line will occupy 623.7 habitat units and will also
result in the partial displacement of one bear. In combination,· these
two facilities account for 90.4 percent of the direct black bear habitat
losses (Table 10).
Construction noise and disturbance and associated aircraft traffic will
also affect bear distribution. Noise from blasting will result in the
loss of 3,641.8 habitat units and the displacement of three black bears.
Aircraft disturbance will decrease the number of available habitat units
by an additional 1,074.2 habitat units and will result in the partial
displacement of one bear. Noise produced by vehicles will have a
negligible effect, resulting in the loss of only 167.9 habitat units.
In total, construction activities will result in the loss of 6,565.0
habitat units and the displacement of six bears. This loss represents
23.6 percent of the habitat available to black bears in the study area.
Because the duration of most of these effects is short-term, it is
expected that bears will be temporarily displaced, but not permanently
lost from the local community.
The Terrestrial Impact Quantification Program was designed to establish
the effects of the project on wildlife habitat and use of that habitat.
Mortality of animals due to direct means, such as hunting, road kills,
or destruction of problem animals was not included in the models.
The current project designs include measures to discourage the
attraction of bears to the camps. Putrescible Wastes will be
incinerated and buried. The landfill will be fenced to prevent bears
from entering the area. In addition, an employee education program will
be conducted to familiarize personnel with sensitive environmental
features of the Project area, including wildlife.
BL-D-123 3-14
Specific procedures that deal with problem animals will be developed in
conjunction with the Alaska Department of Fish and Game.
3.3.4 Mountain Goat
The adverse effects of construction are greater for mountain goats than
for the other indicator species. Facility construction will result in
the direct loss of 740.5 habitat units. This represents 14.1 percent of
the habitat units available to mountain goats. Reservoir development
creates the largest habitat loss with 729.1 habitat units eliminated,
and five goats displaced. Losses due to the reservoir represent 98.5
percent of the total number of habitat units directly affected by
facility construction (Table 11).
Additional indirect habitat losses will occur due to the noise
associated with blasting, aircraft, and vehicles. Noise produced by
blasting will reduce the number of available habitat units by 1,063.0
and will result in the displacement of approximately seven goats.
Aircraft and vehicles will have a smaller effect, resulting in the loss
of 116.0 habitat units and the displacement of one goat.
In combination, direct and indirect losses will result in a decrease of
1,919.5 habitat units, and approximately 13 goats being displaced to
adjacent ranges. This represents a loss of approximately 36 percent of
the habitat units available to mountain goats within the study area.
Habitat losses do not account for isolation of goats from alternate
ranges. Since the construction period is relatively short in the
vicinity of the lake outlet, it is assumed that displaced goats will not
be permanently lost from the local goat community.
The Moose Survey Report (WCC 1984) describes general availability of
additional goat winter range about 1.5 miles north of the Project dam
site. Based upon the present baseline data, it is not possible to
establish the population-level effects on mountain goats which may be
associated with the Bradley Lake Project. During construction, it is
anticipated that the goats will be displaced near Project facilities
BL-D-123 3-15
from portions of their summer and winter range into adjacent ranges.
Based upon current information on mountain goat behavior and
distribution, it is anticipated that mountain goats will return to the
area around the Bradley Lake outlet after construction has ended.
As discussed in the Mitigation Plan, a mountain goat monitoring program
will be established during Project construction and operation to verify
the impact analyses presented in Exhibit E of the License Application.
The HEP analyses results would also be verified. The findings of the
monitoring program can be used to more accurately assess the influences
of the Project on goats occurring in the Project area. Monitoring of
mountain goats will be conducted or done under the field supervision of
the Environmental Field Officer (EFO) making periodic observations of
the goats.
3.3.5 Trumpeter Swan
Trumpeter swan abundance and distribution will also be reduced during
Project construction. Direct losses from facility construction total
658.7 habitat units, which represents the displacement of approximately
three swans. The principal cause for this loss is the development of
the reservoir. Currently, emergent vegetation at the east end of
Bradley Lake provides unutilized feeding habitat for swans. During
reservoir filling, emergent vegetation will not be available, thus
resulting in the loss of 603.7 habitat units (Table 12).
Additional direct habitat losses will occur along the sedge-grass flats
adjacent to Kachemak Bay. Construction of the airstrip, dredged
material disposal site, and barge dock will result in the loss of 2.1,
11.0, and 0.9 habitat units, respectively.
Indirect impacts due to blasting, aircraft flights, and vehicle noise
will also affect the abundance and distribution of swans. Based upon
the response of swans to noise and disturbance, it was estimated that
during construction 627.0 habitat units would be unavailable to swans
due to blasting. This equates to a displacement of approximately two
BL-D-123 3-16
swans. The use of aircraft within the study area will decrease the
number of available habitat units by 30.8, which will result in the
partial displacement of one swan.
will have a negligible effect,
habitat units by 3.8.
It is estimated that vehicle noise
decreasing the number of available
In combination, the direct and indirect influences will result in a
decrease of 1,320.3 habitat units and the displacement of five swans.
This represents a 15.1 percent decrease in the habitat units currently
available to swans in the study area.
3.4 Project Operation
During Project operation, impacts resulting from Project construction on
vegetation and wildlife will be reduced. At the completion of
construction, several temporary facilities, including most of the lower
camp, the upper camp, and the road between the lower camp and the Martin
River delta will be removed and the sites revegetated. Revegetation
will also be conducted at the lower quarry site, the Middle Fork
diversion, and the Nuka River diversion. In addition, the dredged
material disposal area and the Martin River borrow site will be
rehabilitated, and the area under the transmission line right-of-way
will be allowed to naturally revegetate to an early seral stage and then
maintained in that state. All other facilities will remain in place
through the life of the Project.
In accordance with the mitigation policies of the USFWS and ADF&G,
mitigation measures have been incorporated into the Project design.
These measures and the influences that they have on the indicator
species are described in this section. In some cases, additional
mitigation may be required; some measures have been discussed in the
Bradley Lake Hydroelectric Project Draft Mitigation Plan (APA 1985).
These options have not been formalized.
BL-D-123 3-17
3.4.1 Vegetation
Project construction will result in a total of 3,352 acres of vegetation
lost through the placement of facilities and the creation of the
reservoir. However, at the end of the construction phase of the
Project, 1,000 acres of vegetative communities will be replaced through
site rehabilitation.
The lower camp facilities will occupy approximately 43 acres during the
three year construction period. At the end of construction, 29 acres of
this site will be revegetated. The objective of the revegetation
program at the lower camp will be to produce an area that provides
habitat for moose and bear, and is comprised of birch, balsam poplar,
and willow with an understory of fruiting shrubs, grasses, and forbes.
Optimally, the overstory would have a canopy coverage of approximately
50 percent, with the understory having a canopy coverage of
approximately 75 percent. Once this composition was achieved, the
understory would be maintained at a height of five feet or less.
The revegetation program for the lower quarry site (currently closed
coniferous forest and shrubs) would have the same objective as the plan
designed for the lower camp. This program will replace 7.6 acres of
vegetation and also provide moose and bear habitat.
Revegetation will also occur at the upper camp, Middle Fork diversion,
and the Nuka River diversion. However, the objective at these sites
will be to allow them to naturally return to their current vegetation
types. This portion of the program will replace 9.2 acres of
vegetation. The road between the lower camp and the Martin River delta
will also be allowed to return its current vegetation type, replacing
2.4 acres of habitat.
The Martin River borrow site and the dredged material disposal site will
be rehabilitated according to the conceptual plans outlined in the
Interim Final Mitigation Plan. The Martin River site will become a
series of three ponds, each with islands, a littoral zone, and emergent
BL-D-123 3-18
vegetation. The dredged material disposal site will be rehabilitated to
accommodate waterfowl. It will consist of a shallow pond with islands
and emergent vegetation. These two areas will replace 127.7 acres of
habitat.
The largest revegetation effort will occur in the transmission line
corridor. All areas that currently support conifer or deciduous forest
will be revegetated under the same objectives used for the lower camp,
i.e., provide moose and bear habitat. Currently, forest stands occupy
578.0 acres along the right-of-way. An additional 181.6 acres that
currently supports shrub and grass habitats will be revegetated with a
higher proportion of fruiting shrubs and grasses, and will be generally
maintained at a height of less than ten feet. The remaining 2.2 acres
of the transmission line includes unvegetated ponds and streams. No
revegetation program is planned for these areas.
It is anticipated that all revegetation efforts will reach their desired
objective within the first ten years of Project operation. This is
viewed as an appropriate period of time since the objective of the
revegetation efforts are to produce habitats representative of an early
seral stage.
3.4.2 Moose
The influence on moose during Project operation will be significantly
less than during construction. At the peak of the construction period,
7, 588 habitat units, representing 23.5 percent of the moose habitat,
will be unavailable. Following construction, indirect impacts will be
substantially reduced. No blasting will occur and vehicle and aircraft
traffic will not be at a level that would preclude the use of habitats
by moose. Therefore, at the beginning of operations and prior to
habitat rehabilitation, 29,342 habitat units will be available within
the Project study area to support approximately 96 moose. This
represents a reduction of 2,922 habitat units and a displacement of ten
moose from original conditions.
BL-D-123 3-19
Through the revegetation program planned to begin at the start of
operations, 998.7 habitat units, capable of supporting three moose, will
be replaced (Table 13). Revegetation of the lower camp site will
replace 29.6 habitat units, resulting in a new loss from original
conditions of 4.6 habitat units. The lower quarry site and the
transmission line corridor will be revegetated to produce a net gain of
387.1 habitat units. The upper camp, Middle Fork diversion, and Nuka
River diversion will all provide the same number of habitat units
following revegetation as they did prior to construction.
Due to the time required for revegetated sites to reach their optimal
habitat vaiue, the total increases in habitat units are not expected to
occur until ten years after operations begin. After the revegetation
efforts are complete, there will remain a net loss of 1, 923.4 habitat
units (Figure 8) and the displacement of approximately six moose (Figure
9). Without further mitigation, this deficit would be expected to
remain for the life of the Project, since succession of unaffected
vegetation types would not produce a gain or loss in the amount of
habitat units available to moose.
3.4.3 Black Bear
Prior to Project construction, 27,869 habitat units supporting 24 black
bear are available within the study area. During the construction
period, it is anticipated that 6,564.9 habitat units will be made
unavailable to black bears due to direct and indirect Project
influences. At the conclusion of the construction phase, indirect
impacts will become negligible, leaving a loss of 1,681.1 habitat units
and the displacement of one bear due to direct habitat disturbance.
This will result in 26,189 habitat units, capable of supporting 23 black
bears, available within the study area prior to mitigation.
Through the revegetation of the temporary facility sites and maintaining
shrub habitats in the transmission line corridor, 643.1 black bear
habitat units will be replaced (Table 14). Revegetation of the lower
quarry site as a shrub habitat rather than a spruce forest will produce
BL-D-123 3-20
a gain of 0.5 habitat units. The upper camp, Middle Fork diversion, and
Nuka River diversion will be allowed to revegetate to the same type that
existed prior to construction, which will collectively replace 6. 2
habitat units. Although the transmission line will be revegetated to
include fruiting shrubs, the available habitat units will be reduced
from current conditions by 16.4 habitat units.
As described earlier, it is expected that the shrub habitats will attain
their optimal value within ten years after the start of operations.
Without further mitigation, 1,038 habitat units for black bear would be
lost (Figure 10) and one bear would be partially displaced (Figure 11).
The magnitude of this loss is expected to decrease over the life of the
Project. As the shrub habitats that are not affected by the Project
continue through succession, the total number of habitat units in the
study area will decline from 27,870 prior to construction to 27,350 at
the conclusion of the life of the Project. This reduces the average
annual habitat loss for black bear to 778 habitat units, or the partial
displacement of one bear.
3.4.4 Mountain Goats
Prior to the start of construction, 5, 238 habitat units supporting 37
mountain goats are available within the study area. At the peak of the
construction period, the number of available habitat units will be
reduced to 3,319 due to direct and indirect influences. After
construction, the indirect influences will be negligible, since no
blasting will occur and helicopter and vehicle traffic will be
substantially reduced. The elimination of indirect impacts will
increase the number of available habitat units to 4,498. Therefore,
prior to mitigation, there will be a loss of 740.5 habitat units (Table
15; Figure 12), capable of supporting five goats (Figure 13). Of this
total, 729.1 habitat units will be lost due to the creation of the
reservoir. Therefore a relatively small proportion of the total habitat
units lost will be available for revegetation ( 11.4 habitat units).
Facility sites that will be revegetated are the Nuka diversion, Middle
BL-D-123 3-21
Fork diversion, and upper camp. Following revegetation of these sites,
they will provide the same number of habitat units that they provided
prior to construction.
The principal loss of habitat will be due to the creation of the
reservoir (729.1 habitat units). Since only small areas at the Nuka
River diversion, Middle Fork diversion and upper camp are planned for
revegetation, a relatively small proportion of the lost habitat will be
replaced.
3.4.5 Trumpeter Swan
Prior to Project construction, 8,731 habitat units supporting 34 swans
are available within the study area. The influences of Project
operation on trumpeter swans will be substantially less than during
construction. Direct and indirect influences during construction will
result in the loss of 1,320 habitat units, representing 15.1 percent of
the swan habitat available in the study area. As with other indicator
species, following construction, indirect impacts will be negligible.
At the beginning of operations, 8,604 habitat units will be available to
support approximately 33 swans. This is a reduction of 127 habitat
units and the displacement of one swan from original site conditions.
Through the rehabilitation programs planned for the Martin River borrow
pit and the dredged material disposal site, as well as the revegetation
efforts at other facility sites, 175.1 habitat units capable of
supporting one swan will be replaced. The principal mitigative action
is the rehabilitation of the borrow pit and disposal site. After the
revegetation efforts at these sites are complete, the Martin River
borrow pit will provide 42.6 habitat units and the dredged material
disposal site will replace 90.5 habitat units (Table 16). The
revegetation of other Project facilities will provide 42.0 habitat
units. It is anticipated that these habitats will attain their optimal
value within ten years of the start of operations. These efforts will
completely replace the lost habitat value for trumpeter swans (Figures
14 and 15).
BL-D-123 3-22
The trumpeter swan model used three independent variables to predict the
presence of swan habitat in the study area. The three variables were:
Shoreline Development Index; presence of open water; and presence of
emergent vegetation. These variables accounted for 89 percent of the
observed variation in swan distribution within the study area. · Other
variables that were tested in the modeling process and that were deleted
are: proximity to human activity, size of adjacent waterbodies,
altitude, presence of terrestrial vegetation, and water depth. Although
these variables have been found to be important aspects of swan habitat
in other areas, they did not improve the accuracy of the model for the
Bradley Lake area.
When the model was applied to the entire study area, the model predicted
that swan habitat was present in areas where swans have not been ob-
served. These areas included the Martin River delta, the high altitude
lakes above the Bradley River, and Bradley Lake. A visual assessment of
the habitat attributes of these areas confirmed the models predictions
that they are of low habitat quality.
During the impact assessment phase of the program, direct and indirect
impacts were quantified for all areas in which swan habitat was
predicted. Therefore, a loss of habitat units and birds was projected
for Bradley Lake, the upper camp, and a segment of the road between the
lower camp and dam site. This loss was included in the total project
impacts even though swans do not occur in these areas.
A realistic view of the total project impacts would be to eliminate
impact and mitigation values for the upper camp, reservoir, and Bradley
Lake since swans do not occur in these areas. If this was done, the net
result after mitigation is a gain of 120.1 habitat units over current
conditions. This mitigation includes rehabilitation of the Martin River
borrow site according to existing designs. If the completed pit varies
considerably from the conceptual design and it is not used by swans, the
net result after mitigation would be a gain of 77.5 habitat units.
There£ ore, whether the unutilized habitats are included or excluded,
there is a small gain in total habitat units for swans after mitigation.
BL-D-123 3-23
The current design of the Martin River borrow pit would allow it to
serve as shorebird, waterfowl, and swan habitat. The final pit
configuration will include a littoral zone with organic debris and
irregular shoreline. These shallow water zones should provide feeding
habitat for ducks and shorebirds. The lower pit will be close 'to the
high tide line which may entice waterfowl and shorebirds to use the
rehabilitated pits. If ducks and geese are present it is possible that
swans will also use the area.
In reviewing the accuracy of the model's prediction of available swan
habitat at the Martin River borrow pit, it was judged that the model's
prediction of 42.6 habitat units being available following site reha-
bilitation was probably realistic. The presence of these ponds with
shallow-water littoral zones and emergent vegetation near the Battle
Creek tidal wetland should provide suitable feeding and cover habitat
for migrating birds. The physical location of these ponds in the
braided floodplain of the Martin River, or the abrupt change between
floodplain, marine, tidal flat, and lacustrine habitats should not
preclude swans from using the newly created habitats. Also, since the
road to the borrow site will be removed following the construction
period it was not felt that project disturbance related to human activ-
ities or air traffic during the operation phase would substantially
disturb any birds that were utilizing the ponds.
BL-D-123 3-24
z
0
Vi
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til a
4.0 DISCUSSION
4.1 Purpose
The terrestrial impact quantification study was conducted to evaluate
the direct and indirect influences of the Project on four indicator
species. The results of this study were also used to evaluate the
impacts of the Project on other species with similar habitat
requirements and to evaluate the effects of proposed mitigative
measures.
4.2 Vegetation
The direct influences of the Project on vegetation become most important
when they are described as impacts to wildlife habitat. The most
significant losses of vegetation are the elimination of 57 percent of
the low shrub/low willow habitats and 43 percent of the mesic herbaceous
sedge-grass/tall alder/tall willow habitats that exist within the study
area. The majority of these losses will occur during the creation of
the reservoir. These vegetation types provide habitat for moose, black
bear, brown bear, mountain goats, wolverine, beaver, and a variety of
small birds and mammals.
Although the loss of 56 percent of the closed balsam poplar forest may
appear to be significant, only two stands of this type exist within the
study area, and in combination total 67.1 acres. One of these stands is
located along the Fox River, and the second stand is located adjacent to
Battle Creek where the lower camp facilities will be sited. This
vegetation type is relatively unimportant for most species of wildlife,
although moose, bear, and bald eagles are occasionally observed using
this habitat.
In general, a relatively small proportion of the vegetation types will
be significantly affected. While 16 types will be unaffected by the
Project, 19 types will have less than ten percent of their total area
affected. Six vegetation types will be moderately affected through the
BL-D-123 4-1
elimination of between 10 and 20 percent of their total acreage within
the study area, and four vegetation types will have more than 20 percent
of their acreage affected.
The influences of indirect impacts resulting from Project constru~tion,
including dust deposition, altered drainage patterns, and erosion have
not been quantified. These impacts should be negligible since measures
will be instituted to minimize these effects. Descriptions of methods
to minimize indirect impacts are outlined in the Alaska Power
Authority's Best Management Practices manuals.
4.3 Moose
During the construction and operation of the Project, moose will be
adversely affected. The noise and disturbance associated with
construction will likely result in 4,666 habitat units being unavailable
to moose. In addition, 2,922 habitat units will be lost due to facility
placement and the creation of the reservoir. The total of 7,588 habitat
units that will not be available to moose during construction represents
23.5 percent of the moose habitat within the study area.
At the start of operations, the impact to moose will be less
substantial, with only 2, 922 habitat units being unavailable. This
impact will be further reduced by the mitigative measures provided for
in the conceptual designs of the Project. Without further mitigation,
it is estimated that 1,923 habitat units will be unavailable to moose.
This loss represents 6.0 percent of the available moose habitat.
The loss of six percent of available moose habitat is a relatively small
proportion of the total amount of habitat within the study area.
However, 76 percent of this loss will occur at the east end of Bradley
Lake due to inundation by the reservoir. This portion of the study area
seasonally supports between 4 and 13 moose. Due to the extent of the
habitat loss, it is anticipated that these moose will be displaced from
BL-D-123 4-2
Kachemak Creek for the life of the Project. Limited use of the area may
be made by migratory moose; however, the majority of the animals will
likely be displaced to adjacent ranges.
Based upon the habitat quality in the Fox River valley and in the .Boxcar
Hills area, sufficient range most likely exists to support the displaced
animals. Because movement of moose has been documented between the Fox
River valley and Kachemak Creek, it is reasonable to assume that the
displaced animals will move to the Fox River valley.
Additional mitigation of direct and indirect influences of the Project
will be based on habitat with consideration given to the number of
animals affected. For habitats in the Bradley Lake study area, 303
habitat units are required to support one moose. Therefore, the
unmitigated loss of 1,923 habitat units equated to a displacement of 6.3
moose.
The results of the Terrestrial Impact Quantification Program predicted
that the moose will not be present in Kachemak Creek valley after the
reservoir was full. A monitoring program has been proposed in the
Mitigation Plan. The objective of this program will be to observe the
moose in Kachemak Creek valley to establish whether the moose, if
present, are attempting to leave the valley as the reservoir fills.
It is likely that moose will be displaced rather than lost. The concept
of self preservation, and the time required for the reservoir to fill
(over two months), and the land available above Elevation .1180 would
favor displacement.
BL-D-123 4-3
4.4 Black Bear
The influences on bears from Project construction and operation are
expected to be relatively minor. During the construction period, 1,681
habitat units will be lost due to direct impacts, and 4, 884 h.abitat
units will be made unavailable to bears due to noise and disturbance.
The total reduction in habitat units (6 ,565) during the construction
period represents 23.6 percent of the black bear habitat within the
study area.
At the conclusion of the construction phase, the impact will be reduced
to a loss of 1,681 habitat units. Revegetation and other mitigative
measures will reduce the average annual loss to 778 habitat units
through the life of the Project. This decrease in habitat units
represents 2.8 percent of the black bear habitat within the study area.
Due to the low density of black bears within the study area, this
unmitigated loss of habitat will have a negligible effect on the local
black bear population. Based upon the habitat quality in the study
area, approximately 1,161 habitat units are required to support one
black bear. Therefore, the unmitigated loss of 778 habitat units
equates to the partial displacement of 0.67 black bears. This effect
will most likely be noted as a shift in the boundaries of black bear
territories and not the total displacement of one animal.
4.5 Brown Bear
On a regional basis, black bears and brown bears have notable
dissimilarities in their habitat requirements. Brown bears are often
associated with high altitude shrub habitats during the spring and
summer and are also known to den in high altitude areas. During the
seasons when anadromous fish are present, brown bears will often feed on
migrating fish, or fish carcasses along streams. Black bears are more
often associated with woodlands and lower elevation shrub habitats.
They may also forage on anadromous fish and other carrion.
BL-D-123 4-4
Within the Bradley Lake area, the use of habitats by the two species is
more similar. Both species make use of high altitude shrub habitats and
low elevation woodland habitats. No denning has been documented within
the study area by either species. Typically, anadromous fish carcasses
are not present along streams occurring within the Project area,since
the tide removes them before they can be consumed by the bears.
Due to the similarity between the two species with respect to habitat
use in the study area, and the similarity of their responses to noise,
including aircraft, vehicles, and blasting, the quantified black bear
impacts can be extrapolated to brown bears. Based upon the number of
brown bears observed in the study area and estimates from the Kenai
Peninsula on home range size, it is estimated that less than five brown
bears reside in the study area. Using this density, the influences of
the Project on brown bears can be extrapolated from the black bear
analysis by dividing the available and affected number of affected
animals by four. This equates to a loss of 778 habitat units and the
partial displacement of 0.2 brown bears. Similar to the black bears,
this effect will most likely be noted as a shift in the boundaries of
territories and not the displacement of an animal.
4.6 Mountain Goats
Although mountain goats are limited to the higher elevation sites within
the Project area, they will likely be affected by habitat loss and by
noise and disturbance. During the construction period, 740.5 habitat
units will be lost due to facility placement and the creation of the
reservoir. In addition, 1,179.0 habitat units will be unavailable to
goats due to noise and disturbance. The total reduction of 1,919.5
habitat units during this period represents a loss of 36.6 percent of
the available goat habitat.
BL-D-123 4-5
Towards the end of the construction phase of the Project, the loss will
be reduced to 740.5 habitat units. Mitigative efforts will further
reduce this loss to 738.1 habitat units through the life of the Project.
This unmitigated loss will likely result in the displacement of five
goats.
The effect of displacing goats from their range cannot be predicted
based upon the existing goat survey data. However, because the
facilities (including the dam) will not constitute physical barriers to
the goats, it is assumed that goats will have access to alternate ranges
as well as historic winter range along the Bradley River.
4.7 Waterfowl
Ducks, geese, and swans will be impacted adversely by construction
activities; however, impacts associated with habitat losses will be
fully offset during the operation phase of the Project. The principal
waterfowl of concern in the Project area are the migratory birds that
stage and nest in the lower Fox River valley. Nesting success is only
moderate in the upper and middle portions of the Fox River valley and is
poor in the lower valley because spring tides destroy the nests. The
proposed Project will not have a significant impact on waterfowl
nesting. However, the Project will remove a comparatively small area
(approximately 1,320 habitat units) of lightly to moderately used
intertidal sedge-grass waterfowl staging and feeding habitat on the Fox
River flats and upper Kachemak Bay. This loss represents 15.1 percent
of the waterfowl habitat within the study area. Impacts from the Sheep
Point disposal areas and the barge dock on waterfowl will be mitigated
by rehabilitating the disposal area to create waterfowl nesting habitat.
This effort, combined with the rehabilitation of the Martin River borrow
site, will replace all waterfowl habitat.
BL-D-l23 4-6
The waterfowl model derived for this study predicted the occurrence of
trumpeter swans within the project area. High densities of migrating
2 swans (1.8 to 2.5 birds/mi ) were predicted to occur near ponds and
along the tidal flats in Kachemak Bay. These predicted occurrences
paralleled the observations made by the Corps of Engineers Interagency
Study Team. The observed distribution of shorebirds and other waterfowl
was similar, with birds generally distributed along upper bay tidal
flats,
higher.
however, densities for
Krasnow and Halpin
the latter groups were considerably
(1981) reported that shorebirds and
waterfowl were most abundant between Swift Creek and the Bradley River
with most birds being associated with ponds or the tide line.
In general, the swan model can be used to estimate the distribution of
all waterfowl and shorebirds. However at a species specific level
considerable variation exists in both distribution and density. While
dabbling ducks, sandpipers, and phalaropes have a distribution that
conforms well to the swan model, sea ducks and upland shorebirds have a
distribution that is not accurately predicted by the model. Since most
af the shorebirds, dabbling ducks, and gees~ are associated with water
(ponds or the tide line) and few diving ducks or sea ducks are presented
in these location, the swan model only approximates the general dis-
tribution of shorebirds, geese, and dabbling ducks.
To extrapolate the swan model to other species of shorebirds and
waterfowl, a multiplier is applied to the model. The multiplier adjusts
the density of birds to conform to observed densities for the bird group
being evaluated. Currently, the model is based on a bird density of 2.6
2 swans/mi • Table 17 presents the density of waterfowl and shorebirds
that were observed by Krasnow and Halpin (1981).
After adjusting the model to conform to the higher densities for
shorebirds and other waterfowl, summaries of direct and indirect losses
(Table 18) and the influences of mitigation (Tables 19 and 20) are
presented. The net result after mitigation would be an increase in the
number of birds. The model predicts that after mitigation there will be
BL-D-123 4-7
an increase in available habitat, capable of supporting an additional 16
to 22 waterfowl. Shorebird habitat would also increase, providing
habitat for an additional 630 birds during the spring migration.
During the operation phase of the project, disturbance will be
substantially reduced. Blasting will not occur, aircraft flights will
be infrequent and vehicles use of the roads will be substantially less
than during construction.
During the times that aircraft are landing or taking off from the
airstrip, waterfowl will likely be disturbed, particularly during spring
and fall migrations and early winter when birds are abundant in Kachemak
Bay. However, the type of aircraft and frequency of use have not been
established. ·The presence of vehicles on the road between the lower
camp and the airstrip may also result in disturbance to birds on the
adjacent tidal flats during high tides when more birds are closer to
these facilities.
BL-D-123 4-8
5.0 LITERATURE CITED
ALASKA DEPARTMENT OF FISH & GAME. 1982. Statement of Policy on
mitigation of fish and game habitat disruptions.
BAILEY, T. N., A. W. FRANZMAN, P. D. ARNESON, J. L. DAVIS, AND R. E.
LERUSCHE. 1976. Kenai Peninsula moose population identity study,
Alaska Dept. of Fish and Game. Final Report. P-r Proj. W-17-2,
W-17-3, W-17-4, W-17-5, W-17-6, W-17-7. Job No. 1.7R.
BALLARD, W. G., C. L. GARDNER, J. H. WESTLUND, AND J. R. DAU. 1982.
Moose upstream. Susitna Hydroelectric Project, Phase 1, Final
Report, Alaska Department of Fish and Game.
COTTAM, G. AND J. T. CURTIS. 1956. The use of distance measures in
phytosociological sampling. Ecology 37:451-460.
DAUBENMIRE, R. 1974. Plants and environment: a textbook of plant
autecology. Harper and Row, New York.
HOLDERMANN, D. A. 1983. An assessment of the impact of the Bradley
Lake Hydroelectric Project on selected wildlife populations.
Unpublished Report, Alaska Department of Fish and Game, Homer,
Alaska.
KRANSNOW, L. D. AND M. A. HALPIN. 1981. Potential impacts of the
Bradley Lake Hydroelectric Project on birds: a preconstruction
study, National Fisheries Research Center, Marine Bird Section,
U.S. Fish and Wildlife Service, Anchorage.
RAPPOPORT, A., L. SHEA, AND L. HALPIN. 1981. Application of the U.S.
Fish and Wildlife Service's Habitat Evaluation Procedures to the
proposed Bradley Lake Project, Alaska. USFWS Western Alaska
Ecological Services, Anchorage, Alaska.
BL-D-123 5-l
SCHWARTZ, C. C. AND A. W. FRANZMANN. 1980. Population ecology of the
Kenai Peninsula black bear. Alaska Department of Fish and Game.
Fed. Aid. Wildlife Restor. Project Progress Report. Project
W-17-11.
U.S. FISH AND WILDLIFE SERVICE. 1980a. Terrestrial habitat evaluation
criteria handbook -Alaska. Division of Ecological Services,
USFWS, Anchorage, Alaska.
U.S. FISH AND WILDLIFE SERVICE. 1980b. Habitat Evaluation Procedures.
ESM 102. Division of Ecological Services, USFWS, Department of the
Interior, Washington, D. C.
U.S. FISH AND WILDLIFE SERVICE. 1980c.
Evaluation Procedures, Chapter 1,
Washington, D. C.
Implementation of Habitat
General. 100 ESM 1, USFWS,
U.S. FISH AND WILDLIFE SERVICE. 1980d. Habitat as a basis for
environmental assessment. 101 ESM, USFWS, Washington, D. C.
U.S. FISH AND WILDLIFE SERVICE. 1981. U.S. Fish and Wildlife Service
Mitigation Policy, Part III, Federal Register, Vol. 46 (15).
U.S. FISH AND WILDLIFE SERVICE. 1982. Appendix B: Bradley Lake
Hydroelectric Project, Homer, Alaska. Final Coordination Report.
USFWS Western Alaska Ecological Services, Anchorage, Alaska. In:
U.S. Army Corps of Engineers. 1982. Bradley Lake Hydroelectric
Project, Alaska. Final Environmental Impact Statement. Alaska
District, U.S. Army Corps of Engineers.
VIERECK, L. A. AND C. T. DYRNESS. 1980. A preliminary classification
system for vegetation of Alaska. Pacific Northwest Forest and
Range Experiment Station, USDA Forest Service.
BL-D-123 5-2
WOODWARD-CLYDE CONSULTANTS. 1983. Bradley River instream flow studies.
In: Stone and Webster Engineering Corporation, 1983. Bradley Lake
Hydroelectric Power Project Feasib:tli ty Study, Vol. 3. Prepared
for the Alaska Power Authority.
WOODWARD-CLYDE CONSULTANTS. 1984. Moose survey report. Prepared for
Stone and Webster ET.lgineering Corporation and the Alaska Power
Authority.
BL-D-123 S-3
Table 1. Habitat attributes considered for each indicator species. 1
Terrestrial or aquatic habitat
Percent cover by alder
Percent cover by browse species
Percent cover by forbes
Percent cover by Salix spp.
Percent cover by ~us spp.
Percent cover by Betula spp.
Percent cover by shrubs and trees
Percent cover by intermediate
height browse species
Percent cover by conifer species
Percent cover by Calamagrostis spp.
Percent cover by Athyrium spp.
Percent cover by low evergreen spp.
Percent cover by gramminoids
Percent cover by small fruiting
shrubs
Percent cover by tall fruiting
shrubs
Mean browse height
Distance to cover
Terrain type
Snow depth
Distance to escape habitat
Elevation
Presence of open water in winter
Presence of emergent vegetation
Shoreline Index of lakes
Diversity of fall forage
Distance to shrub habitats
Hunter access
Distance to anadromous fish
Aspect
Diversity of spring food
Den site availability
1 + used in final model
Moose
+
0
+
0
0
0
0
+
0
+
+
+
+
0
Black
Bear
+
+
+
+
+
0
+
0
0
0
0
0 considered but not used in final model
not considered
BL-D-123
SPECIES
Mountain TrUmpeter
Goat Swan
+
0
0
+
0
+
~
+
0
0
+
+
+
Table 2. Descriptions, acreages, percent cover, and codes for vegetation
types found in the Bradley Lake hydroelectric project area, 1980
(after Rappoport et al. 1981)
Code Description Acres Percent Cover
Subtotal Total Subtota'l Total
CONIFEROUS FORESTS
10 Closed coniferous forest 8913.9 16.9
Open coniferous forest 6234.7 11.8
20 open coniferous forest 1628.9 3.1
22 open coniferous forest/tall
alder 1970.5 3.7
23 open coniferous forest/tall
alder/low willow/mesic herbaceous
sedge grass 427.6 0.8
25 open coniferous forest/low alder 119.9 0.2
26 open coniferous forest/bog 651.1 1.2
27 open coniferous forest/low willow 935.3 1.8
28 open coniferous low shrub/low
willow 486.8 0.9
39 open coniferous forest/tall
grass on flats 14.6 0.03
DECIDUOUS FORESTS
Closed deciduous forest 82.8 0.16
41 closed paper birch forest 15.7 0.03
42 closed balsam poplar forest 67.1 0.13
Open deciduous forest 922.6 1.7
51 open balsam poplar forest 300.2 0.6
52 open balsam poplar forest/
tall willow-131.5 0.3
53 open deciduous/tall grass -flats 3.8 0.01
55 open balsam poplar forest/
tall alder 35.0 0.07
66 open balsam poplar forest/
fresh water herbaceous sedge grass 72.2 0.1
67 open balsam poplar forest/tall
grass on flats 22.0 0.04
64 open paper birch forest 12.9 0.02
62 open birch forest/tall alder 332.8 0.6
65 open birch forest/tall grass
on flats 12.2 0.02
BL-D-123
Table 2. continued
Code Description Acres Percent Cover
Subtotal Total Subtotal Total
MIXED FORESTS 434.7 0.8
71 Mixed spruce-balsam poplar forest,
closed and open 340.4 0.6
72 -Mixed spruce-birch forest, closed
and open 94.3 0.2
TALL GRASS TYPES 1377.7 2.6
81 tall grass on slopes 25.7 0.05
84 tall grass on flats 716.7 1.4
85 tall grass on flats/tall alder 184.6 0.3
88 tall grass on flats/tall alder/
fresh water herbaceous sedge grass 428.0 0.8
86 tall lyme grass 22.7 0.04
SHRUB TYPES
Shrub tundra 5145.7 9.8
90 shrub tundra 2847.2 5.4
92 shrub tundra/tall alder/
low willow 1420.1 2.7
94 shrub tundra/low shrub 878.4 1.7
Tall alder 7769.2 14.7
101 tall alder 7116.5 13.5
102 tall alder/low willow 23.8 0.04
103 tall alder/fresh water herbaceous
sedge grass 220.8 0.4
104 tall alder/low shrub 395.9 0.7
105 Tall willow -no pure type 12.2 0.02
Low shrub 3247.1 6.2
110 low shrub 233.4 0.4
111 low alder 9.2 0.02
112 low willow 1421.8 2.7
113 low shrub bog 1582.7 3.0
BL-D-123
Table 2. continued
Code
121
122
123
124
125
126
131
132
141
151
142
152
143
153
170
180
190
Total
Description
SEDGE-GRASS TYPES
mesic herbaceous sedge grass
mesic herbaceous sedge grass/
tall alder
mesic herbaceous sedge grass/
tall alder/tall willow
mesic herbaceous sedge grass/
tall alder/low willow
fresh water herbaceous sedge grass
saltwater herbaceous sedge grass
UNVEGETATED AREAS
Water bodies
pond
lake
tidal river or stream
tidal river or stream/floodplain
low gradient perennial river
or stream
low gradient perennial river
or stream/floodplain
high gradient perennial river
or stream
high gradient perennial river
or stream/floodplain
Bare ground/disturbed
bare rock
snow field, glacier
culturally influenced land
BL-D-123
Acres
Subtotal Total
155.0
1483.9
1372.8
731.2
1152.4
3847.3
9596.9
109.2
1785.4
3248.9
3626.9
346.5
301.4
53.0
44.6
254.5
1.1
188.2
65.2
8742.6
9851.4
52722.4
Percent Cover
Subtotal Total
0.3
2.8
2.6
1.4
2.2
7.3
18.2
0.4
3.4
6.2
6.9
0.7
0.6
0.1
0.08
0.5
o.o
0.4
0.1
16.6
18.7
Table 3. Density and suitability indices for moose in the Bradley Lake study
Total
area.
Modeled
Density
(moose/mi 2 )
0
1.28
1.34
1.41
1.47
1.54
1.60
1.66
1. 73
1.86
1.92
1.98
2.11
BL-D-123
Acreage
9174.1
5568.9
3555.4
4711.0
7586.1
1501.3
9615.4
1638.0
623.9
2550.7
4474.0
237.7
1485.3
52721.8
Number
of
Moose
0
11.14
7.47
10.36
17.45
3.60
24.04
4.26
1.68
7.40
13.42
0.74
4.90
106.46
HSI Acreage
0 9174.1
0.606 5568.9
0.636 3555.4
0.667 4711.0
0.697 7586.1
0.727 1501.3
0.758 9615.4
0.788 1638.0
0.818 623.9
0.879 2550.7
0.909 4474.0
0.939 237.7
1.000 1485.3
52721.8
Habitat
Units
0
3374.76
2261.21
3142.22
5287.54
1091.47
7288.47
1290.78
510.35
2242.03
4066.88
223.18
1485.26
32264.15
Table 4. Density and suitability indices for black bear in the Bradley Lake
study area.
Total
Modeled
Density
(bear/mi 2 )
0
0.05
0.10
0.16
0.22
0.23
0.28
0.33
0.34
0.36
0.38
0.42
0.44
0.48
0.54
0.55
BL-D-123
Acreage
8464.9
2718.5
511.2
5035.6
1565.9
836.6
3465.8
582.5
1666.7
744.1
8311.5
1443.5
10703.8
3654.6
1372.5
1644.0
52721.8
Number
of HSI
Bear
0 0
0.22 0.093
0.08 0.163
1.22 0.282
0.54 0.395
0.30 0.419
1. 52 0.512
0.30 0.581
0.86 0.605
0.42 0.651
4.98 0.698
0.96 0.767
7.28 0.791
2.74 0.870
1.16 0.977
1.42 1.000
24.00
Acreage
8464.9
2718.5
511.2
5035.6
1565.9
836.6
3465.8
582.5
1666.7
744.1
8311.5
1443.5
10703.8
3654.6
1372.5
1644.0
52721.8
Habitat
Units
0
252.82
83.33
1419.06
618.52
350.52
1774.51
338.43
1008.37
484.40
5801.43
1107. 16
8466.68
3179.42
1340.97
1644.04
27869.66
Table 5. Density and suitability indices for mountain goats in the Bradley Lake
study area.
Total
Modeled
Density
(goats/mi2 )
0
0.64
1.28
3.84
4.48
BL-D-123
Acreage
37654.7
544.1
13054.7
289.9
1178.4
52721.8
Number
of
Goats
0
0.54
26.11
1. 74
8.25
36.64
HSI
0
0.143
0.286
0.857
1.000
Acreage
37654.7
544.1
13054.7
289.9
1178.4
52721.8
Habitat
Units
0
77.81
3733.64
248.48
1178.44
5238.36
Table 6. Density and suitability indices for trumpeter swans in the Bradley
Lake study area.
Total
Modeled
Density
(swans/mi2 )
0
0.32
0.64
0.70
0.96
1.28
1.47
1.66
1.79
2.04
2.37
2.50
BL-D-123
Acreage
33190.8
5490.8
3486.3
619.5
2035.5
204.8
790.8
1807.5
521.6
2844.0
785.6
945.1
52721.8
Number
of
Swans
0
2.75
3.49
0.68
3.05
0.41
1.82
4.70
1.46
9.10
2.91
3.69
34.05
HSI Acreage
0 33190.8
0.128 5490.5
0.256 3486.3
0.282 619.5
0.385 2035.5
0.513 204.8
0.590 790.8
0.667 1807.5
o. 718 521.6
0.821 2844.0
0.949 785.6
1.000 945.1
52721.8
Habitat
Units
0
702.78
892.48
174.69
783.67
105.07
466.56
1205.57
374.47
2334.92
745.56
945.09
8730.86
Table 7. Acreage occupied by each facility.
Facility Code Facility Name Acreage
1 Lower camp staging area 19.3
2 Lower camp solid waste disposal area 5.3
3 Lower camp organic stockpile 3.9
4 Lower camp buildings 14.9
.5 Upper camp 5.8
6 Lower quarry site 7.6
7 Powerhouse 5.0
8 Airstrip 8.9
9 Martin River borrow site 86.2
10 Barge Dock 3.8
14 Waste area at dam 5.0
15 Upper quarry site at dam 4.6
16 Dam 8.6
17 Middle Fork diversion 2.0
18 Reservoir 2577.4
19 Bradley Lake 1568.0
20 Nuka River diversion 0.4
21 Sheep Point dredged material disposal area 34.7
23 Transmission Line 761.8
25 Roads 46.2
TOTAL 5169.4
BL-D-123
Table 8. Acreage of vegetation types affected by facilities.
Vegetation Code Acres Available Acres Occupied Percent Facilities
in Study Area by facilities Occupied Involved
10 8913.9 402.8 4.5 3,4,6,7,8,
9,21,21,25
20 1628.9 57.6 3.5 23
22 1970.5 8.5 0.4 23, 25
23 427.6 14.7 3.4 5, 23, 25
25 119.9 0 0
26 651.1 13.7 2.1 23
27 935.3 62.9 6.7 23
28 486.8 41.8 8.6 23
39 14.6 0 0
41 15.7 0.3 1.9 25
42 67.1 37.3 55.6 1,2,3,4,25
51 300.2 0 0
52 131.5 0 0
53 3.8 0 0
55 35.0 0.1 0.3 25
62 332.8 18.7 5.6
64 12.9 0 0
65 12.2 0 0
66 72.2 0 0
67 22.0 0 0
71 340.4 26.0 7.6 23
72 94.3 0.8 0.8 25
81 25.7 0 0
84 716.7 21.2 3.0 23
85 184.6 0 0
86 22.7 2.5 11.0 1' 2, 25
88 428.0 0 0
90 2847.2 4.7 0.2 16.18,25
92 1420.1 1.2 0. 1 17
94 878.4 0 0
101 7116.5 343.2 4.8 9,14,15,16
17,18,23,25
102 23.8 0 0
103 220.8 7.0 3.2 23
104 395.9 77.6 19.6 18
105 12.2 1.8 14.8 23
110 233.4 0 0
111 9.2 0 0
BL-D-123
Table 8. (continued)
Vegetation Code
112
113
121
122
123
124
125
126
131
132
141
142
143
151
152
153
170
180
190
TOTAL
BL-D-123
Acres Available
in Study Area
1421.8
1582.7
155.0
1483.9
1372.8
731.2
1152.4
3847.3
190.2
1785.4
3248.9
346.5
53.0
3626.9
301.4
44.6
1.1
188.2
65.2
52722.4
Acres Occupied
by facilities
810.7
79.9
15.5
211.2
595.8
90.2
343.4
61.2
5.0
1568.8
27.1
84.1
2.5
87.0
97.5
0
0
0.2
0
5224.5
Percent
Occupied
57.0
5.0
10.0
14.2
43.4
12.3
29.8
1.6
2.6
87.9
0.8
24.3
4.7
2.4
32.3
0
0
0.1
0
9.9
Facilities
Involved
18,19,20,23
6,23,25
23
16. 18
18
18, 25
18. 23
7, 8, 21,
23, 25
18, 23
5, 19, 25
10,23
18, 23
15, 16, 18
9,10,21,25
4,18,23,25
20
Table 9. Summary of direct and indirect losses of habitat and subsequent
displacement of moose during the construction period.
Direct Loss
Facility
Lower camp staging area
Lower ca~p solid waste disposal area
Lower camp organic stockpile
Lower camp buildings
Upper camp
Lower quarry site
Powerhouse
Airstrip
Martin River borrow site
Barge Dock
Waste area at dam
Upper quarry site at dam
Dam
Middle Fork diversion
Reservoir
Bradley Lake
Nuka River diversion
Sheep Point dredged material disposal area
Transmission Line
Roads
Total Direct Loss
Indirect Loss
Blasting
Aircraft noise
Vehicle noise
Total Indirect Loss
TOTAL LOSS
BL-D-123
Number of Habitat Number of
Units Lost Animals Displaced
16.8 0.06
3.2 0.01
2.4 0.01
11.8 0.04
3.7 0.01
4.6 0.02
3.7 0.01
6.5 0.02
10.8 0.04
0 0
3.8 0.01
3.5 0.01
6.5 0.02
1.4 0
2224.0 7.34
0 0
0.4 0
20.4 0.07
569.8 1.88
28.8 0.09
2922.1 9.64
4156.4 13.71
497.8 1.64
11.9 0.04
4666.1 25.03
7588.2 25.03
Table 10. Summary of direct and indirect losses of black bear habitat and
subsequent displacement of bear during the construction period.
Facility
Direct Loss
Lower camp staging area
Lower camp solid waste disposal area
Lower camp organic stockpile
Lower camp buildings
Upper camp
Lower quarry site
Powerhouse
Airstrip
Martin River borrow site
Barge Dock
Waste area at dam
Upper quarry site at dam
Dam
Middle Fork diversion
Reservoir
Bradley Lake
Nuka River diversion
Sheep Point dredged material disposal area
Transmission Line
Roads
Total Direct Loss
Indirect Loss
Blasting
Aircraft noise
Vehicle noise
Total Indirect Loss
TOTAL LOSS
BL-D-123
Number of Habitat Number of
Units Lost Animals D~splaced
14.8
4.1
3.0
11.4
5.1
5.3
3.1
5.7
34.6
0
3.9
3.7
6.8
1.0
896.1
0
0.1
26.0
623.7
32.7
1681.1
3641.8
1074.2
167.9
4883.9
6565.0
0.04
0
0
0
0
0
0
0
0.04
0
0
0
0
0
0.78
0
0
0.02
0.54
0.02
1. 44
3.14
0.92
0.14
4.20
5.64
Table 11. Summary of direct and indirect losses of mountain goat habitat
and subsequent displacement of goats during the construction period.
Facility
Direct Loss
Lower camp staging area
Lower camp solid waste disposal area
Lower camp organic stockpile
Lower camp buildings
Upper camp
Lower quarry site
Powerhouse
Airstrip
Martin River borrow site
Barge Dock
Waste area at dam
Upper quarry site at dam
Dam
Middle Fork diversion
Reservoir
Bradley Lake
Nuka River diversion
Sheep Point dredged material disposal area
Transmission Line
Roads
Total Direct Loss
Indirect Loss
Blasting
Aircraft noise
Vehicle noise
Total Indirect Loss
TOTAL LOSS
BL-D-123
Number of Habitat
Units Lost
0
0
0
0
1.7
0
0
0
0
0
1.4
1.3
2.5
0.6
729.1
0
0.1
0
0
3.8
740.5
1063.0
113.9
2.1
1179.0
1919.5
Number of
Animals Displaced
0
0
0
0
0.01
0
0
0
0
0
0.01
0.01
0.02
0
5.10
0
0
0
0
0.03
5.18
7.43
0.80
0.02
8.25
13.43
Table 12. Summary of direct and indirect losses of trumpeter swan habitat
and subsequent displacement of swans during the construction period.
Facility
Direct Loss
Lower camp staging area
Lower camp solid waste disposal area
Lower camp organic stockpile
Lower camp buildings
Upper camp
Lower quarry site
Powerhouse
Airstrip
Martin River borrow site
Barge Dock
Waste area at dam
Upper quarry site at dam
Dam
Middle Fork diversion
Reservoir
Bradley Lake
Nuka River diversion
Sheep Point dredged material disposal area
Transmission Line
Roads
Total Direct Loss
Indireet Loss
Blasting
Aircraft noise
Vehicle noise
Total Indirect Loss
TOTAL LOSS
BL-D-123
Number of Habitat Number of
Units Lost Animals D~splaced
0
0
0
0
2.3
0
1.3
2.1
0
0.9
0
0
0
0
0
603.7
0
8.9
35.9
3.5
658.7
627.0
30.8
3.8
661.6
1320.3
0
0
0
0
0.01
0
0.01
0.01
0
0.01
0
0
0
0
0
2.35
0
0.04
0.14
0.01
2.58
2.45
0.12
0.03
2.60
5.18
Table 13. Influence of mitigation on moose.
Facility Habitat Units Number of Animals
Direct Loss Mitigation Direct Loss Mitigation
Lower camp staging area 16.8 20.0 0.06 0.06
Lower camp solid waste disposal area 3.2 5.5 0.01 0.02
Lower camp organic stockpile 2.4 4.1 0.01 0.01
Lower camp buildings 11.8 0 0.04 0
Upper camp 3.7 3.7 0.01 0.01
Lower quarry site 4.6 7.9 0.02 0.03
Powerhouse 3.7 0 0.01 0
Airstrip 6.5 0 0.02 0
Martin River borrow site 10.8 0 0.04 0
Barge Dock 0 0 0 0
Waste area at dam 3.8 0 0.01 0
Upper quarry site at dam 3.5 0 0.01 0
Dam 6.5 0 0.02 0
Middle Fork diversion 1.4 1.4 0 0
Reservoir 2224.0 0 7.34 0
Bradley Lake 0 0 0 0
Nuka River diversion 0.4 0.4 0 0
Sheep Point dredged material
disposal area 20.4 0 0.07 0
Transmission Line 569.8 953.6 3.16
Roads 28.8 2.1 1.88 0.01
Total 2922.1 998.7 0.09 3.30
Net Loss 1923.4 6.34
BL-D-123
Table 14. Influence of mitigation on black bears
Facility Habitat Units Number of Animals
Direct Loss Mitigation Direct Loss Mitigation
Lower camp staging area 14.8 14.6 0.04 0.02
Lower camp solid waste disposal 4.1 4.0 0 0
Lower camp organic stockpile 3.0 3.0 0 0
Lower camp buildings 11.4 0 0 0
Upper camp 5. 1 5.1 0 0
Lower quarry site 5.3 5.8 0 0
Powerhouse 3.1 0 0 0
Airstrip 5.7 0 0 0
Martin River borrow site 34.6 0 0.04 0
Barge Dock 0 0 0 0
Waste area at dam 3.9 0 0 0
Upper quarry site at dam 3.7 0 0 0
Dam 6.8 0 0 0
Middle Fork diversion 1.0 1.0 0 0
Reservoir 896.1 0 0.78 0
Bradley Lake 0 0 0 0
Nuka River diversion 0.1 0.1 0 0
Sheep Point dredged material 26.0 0 0.02 0
disposal area
Transmission Line 623.7 607.3 0.54 0.48
Roads 32.7 2.4 0.02 0
Total 1681.1 643.1 1.44 0.50
Net Loss 1038 0.94
BL-D-123
Table 15. Influence of mitigation on mountain goats.
Facility Habitat Units Number of Animals
Direct Loss Mitigation Direct Loss Mitigation
Lower camp staging area 0 0 0 0
Lower camp solid waste disposa 0 0 0 0
Lower camp organic stockpile 0 0 0 0
Lower camp buildings 0 0 0 0
Upper camp 1.7 1.7 0.01 0.01
Lower quarry site 0 0 0 0
Powerhouse 0 0 0 0
Airstrip 0 0 0 0
Martin River borrow site 0 0 0 0
Barge Dock 0 0 0 0
Waste area at dam 1.4 0 0.01 0
Upper quarry site at dam 1.3 0 0.01 0
Dam 2.5 0 0.02 0
Middle Fork diversion 0.6 0.6 0 0
Reservoir 729.1 0 5.10 0
Bradley Lake 0 0 0 0
Nuka River diversion 0.1 0.1 0 0
Sheep Point dredged material 0 0 0 0
disposal area
Transmission Line 0 0 0 0
Roads 3.8 0 0.03 0
Total 740.5 2.4 5.18 0.01
Net Loss 738.1 5.17
BL-D-123
Table 16. Influence of mitigation on trumpeter swans.
Facility Habitat Units Number of Birds
Direct Loss Mitigation Direct Loss Mit~gation
Lower camp staging area 0 0 0 0
Lower camp solid waste disposa 0 0 0 0
Lower camp organic stockpile 0 0 0 0
Lower camp buildings 0 0 0 0
Upper camp 2.3 2.3 0.01 0.01
Lower quarry site 0 0 0 0
Powerhouse 1.3 0 0.01 0
Airstrip 2.1 0 0.01 0
Martin River borrow site 0 42.6 0 0.16
Barge Dock 0.9 0.3 0.01 0
Waste area at dam 0 0 0 0
Upper quarry site at dam 0 0 0 0
Dam 0 0 0 0
Middle Fork diversion 0 0 0 0
Reservoir 0 330.7 0 1.29
Bradley Lake 603.7 201.2 2.35 0.78
Nuka River diversion 0 0 0 0
Sheep Point dredged material 8.9 90.5 0.04 0.35
disposal area
Transmission Line 35.9 35.9 0.14 0.14
Roads 3.5 3.5 0.01 0.01
Total 658.7 707.0 2.58 2.74
Net Gain 48.3 0.16
BL-D-123
Table 17 Density of waterfowl and shorebirds reported for the study
area (adapted from Krasnow and Halpin 1981).
Swans
Geese
Dabbling Ducks
Diving Ducks
Total Waterfowl
Total Shorebirds
BL-D-132
Spring
2.6
15.5
212.4
36.3
266.8
10207.2
2 Density (birds/mi )
Fall
2.6
82.9
146.8
96.2
328.5
32.0
Table 18 Summary of direct and indirect losses of waterfowl and
shorebird habitat and subsequent displacement of birds
due to Project construction.
Number Number of Birds Dis2laced
of Habitat Waterfowl Shorebirds
Facility Units Lost Spring Fall Spring Fall
Direct Loss
Lower camp staging
area 0 0 0 0 0
Lower camp solid waste
disposal area 0 0 0 0 0
Lower camp organic
stockpile 0 0 0 0 0
Lower camp buildings 0 0 0 0 0
Upper camp 2.3 1.0 1.3 39.3 0.1
Lower quarry site 0 0 0 0 0
Powerhouse 1.3 1.0 1.3 39.3 0.1
Airstrip 2.1 1.0 1.3 39.3 0.1
Martin R. borrow site 0 0 0 0 0
Barge Dock 0.9 1.0 1.3 39.3 0.1
Waste area at dam 0 0 0 0 0
Upper quarry site at dam 0 0 0 0 0
Dam 0 0 0 0 0
Middle Ford diversion 0 0 0 0 0
Reservoir 0 0 0 0 0
Bradley Lake 603.7 235.0 296.1 9226.1 28.9
Nuka River diversion 0 0 0 0 0
BL-D-132
Table 18, Continued
Number Number of Birds Diselaced
of Habitat Waterfowl Shorebirds
Facility Units Lost Spring Fall Spring Fall
Sheep Point dredged
material disposal area 8.9 4.0 5.0 157.0 0.5
Transmission Line 35.9 14.0 17.6 549.6 1.7
Roads 3.5 1.0 1.3 39.3 0.1
Total Direct Loss 658.7 258.0 325.2 10129.2 31.6
Indirect Loss
Blasting 627.0 245.0 308.7 9618.7 30.2
Aircraft Noise 30.8 12.0 15.1 471.1 1.5
Vehicle Noise 3.8 3.0 3.8 117.8 0.4
Total Indirect Loss 661.6 260.0 327.6 10207.6 32.1
Total Loss 1320.3 518.0 652.8 20336.6 63.7
BL-D-132
Table 19 Influence of Mitigation on waterfowl.
Number of Birds
Habitat Units SEring Fall
Direct Miti-Direct Miti-Direct Miti-
Facility Loss gat ion Loss gat ion Loss ga.tion
Lower camp
staging area 0 0 0 0 0 0
Lower camp
solid waste
disposal 0 0 0 0 0 0
Lower camp
organic
stockpile 0 0 0 0 0 0
Lower camp
buildings 0 0 0 0 0 0
Upper camp 2.3 2.3 1.0 1.0 1.3 1.3
Lower quarry
site 0 0 0 0 0 0
Powerhouse 1.3 0 1.0 0 1.3 1.3
Airstrip 2.1 0 1.0 0 1.3 0
Martin River
borrow site 0 42.6 0 16.0 0 20.2
Barge Dock 0.9 0.3 1.0 0.1 1.3 0.1
Waste area
at dam 0 0 0 0 0 0
Upper quarry
site at dam 0 0 0 0 0 0
Dam 0 0 0 0 0 0
Middle Fork
Diversion 0 0 0 0 0 0
Reservoir 0 330.7 o· 129.0 0 162.5
BL-D-132
Table 19, Continued
Number of Birds
Habitat Units
Direct Miti-
Spring Fall
Direct Mi ti-=-D~i r_e_c_t--~M:-:-1-:--t~i:----
Facility Loss gat ion Loss gat ion Loss gat ion
Bradley Lake 603.7 201.2 235.0 78.0 296.1 98.3
Nuka Glacier
Diversion 0 0 0 0 0 0
Sheep Point
dredged mater-
ial disposal
area 8.9 90.5 4.0 35.0 5.0 44.2
Transmission
Line 35.9 35.9 14.0 14.0 17.6 17.6
Roads 3.5 3.5 1.0 1.0 1.3 1.3
Total 658.7 707.0 258.0 274.1 325.2 346.8
Net Gain 48.3 16.1 21.6
BL-D-132
Table 20 Influence of Mitigation on shorebirds.
Number of Birds
Habitat Units S2ring Fall
Direct Miti-Direct Miti-Direct Miti-
Facility Loss gat ion Loss gat ion Loss ga.tion
Lower camp
staging. area 0 0 0 0 0 0
Lower camp
solid waste
disposal 0 0 0 0 0 0
Lower camp
organic
stockpile 0 0 0 0 0 0
Lower camp
buildings 0 0 0 0 0 0
Upper camp 2.3 2.3 39.3 39.3 0.1 0.1
Lower quarry
site 0 0 0 0 0 0
Powerhouse 1.3 0 39.3 0 0.1 0
Airstrip 2.1 0 39.3 0 0. 1 0
Martin River
borrow site 0 42.6 0 628.2 0 2.0
Barge Dock 0.9 0.3 39.3 2.0 0.1 0.1
Waste area
at dam 0 0 0 0 0 0
Upper quarry
site at dam 0 0 0 0 0 0
Dam 0 0 0 0 0 0
Middle Fork
Diversion 0 0 0 0 0 0
Reservoir 0 330.7 0 5064.9 0 15.9
BL-D-132
Table 20, continued
Number of Birds
Habitat Units
Direct Miti-
Spring ~---F_a_l_l~~~---
Direct Miti-Direct Miti-
Facility Loss gat ion Loss gat ion Loss
Bradley Lake 603.7 201.2 9226.1 3062.3 28.9 9.6
Nuka Glacier
Diversion 0 0 0 0 0 0
Sheep Point
dredged mater-
ial disposal
area 8.9 90.5 157.0 1374.0 0.5 4.3
Transmission
Line 35.9 35.9 549.6 549.6 1.7 1.7
Roads 3.5 3.5 39.3 39.3 0.1 0.1
Total 658.7 707.0 10129.2 10759.6 31.6 33.8
Net Gain 48.3 630.4 2.2
BL-D-132
U)
o-l
I:LI
:><: ~
H 0 --<
!@ )::
I:LI U)
p.. I:LI ~
ea H u
I:LI
p..
U)
MOOSE
DENSITY 1
[[3.6991 + (0.0203X 1) + (-0.3705X2 ) + (0.0096X 3) + (-0.1233X4 )
+ (-0.0076X5) + (0.000451X6 )]X7 ] * 125]
VARIABLES
x 1 percent canopy cover by conifers. measured in Daubenmire cover
classes.
x2 terrain type. measured as undaulating (X 2 = 1) or flat (X 2 = 2)
x3 percent browse measured as the combined Daubenmire cover class for
Betula paperifera, Populus balsamifera, and Salix Spp.
x4 browe height. measured in feet.
percent canopy coverage by shrubs and trees.
Daubenmire cover classes.
x6 distance to cover. measured in yards.
terrestrial versus aquatic. terrestrial 1, aquatic
SIGNIFICANCE OF VARIABLES
PARTIAL F VALUES DF 13/336
F 27.20 p 0.01
F 12.56 p 0.01
F 6.16 p 0.01
BL-D-132 A - 2
measured in
0
x4 F = 16.96 p 0.01
x5 F 4.43 p 0.01
x6 F = 16.03 p 0.01
MULTIPLE REGRESSION COEFFICIENT
R = 57.73 DF = 336 p 0.01
ANALYSIS OF VARIANCE
SOURCE
REGRESSION
RESIDUAL
TOTAL
BL-D-132
DF
13
336
349
ss
43.37
86.75
130.13
MS
3.33
0.26
A - 3
F
12.90
p
0.01
BLACK BEAR
DENSITY [[2.92 + (0.0203X 1) + (0.012SX 2) + (-0.0025SX3 ) + (0.0134X4 )
+ (-0.0009X5))]X7 ]/5000
VARIABLES
X1 percent cover by Equisetum, gramminoids, forbes, and ferns.
measured in Daubenmire cover class means.
x2 percent cover by small fruiting shrubs. measured in Daubenmire
cover class means.
x3 distance to cover (areas with trees greater than eight inches DBH).
measured in yards.
x4 percent cover by tall fruiting shrubs. measured in Daubenmire
cover class means.
x5 distance to tall shrubs. measured in yards.
terrestrial versus aquatic. terrestrial 1, aquatic = 0.
SIGNIFICANCE OF VARIABLES
PARTIAL F VALUES DF = 10/339
x1 F 35.36 p 0.01
x2 F 8.90 p 0.01
x3 F 164.79 p 0.01
x4 F 12.14 p 0.01
BL-D-132 A-4
x5 F = 26.98 p 0.01
x6 F 7.95 p 0.01
MULTIPLE REGRESSION COEFFICIENT
R = 85.26 DF = 339 p 0.01
ANALYSIS OF VARIANCE
SOURCE
REGRESSION
RESIDUAL
TOTAL
BL-D-132
DF
10
339
349
ss
434.88
163.32
598.20
MS
43.49
0.48
A - 5
F
90.27
p
0.01
MOUNTAIN GOAT
DENSITY
VARIABLES
snow distribution. wind swept areas (XI
=I), and all other areas (XI= 0).
x2 elevation. measured in feet.
2), collection areas (X 1
x3 percent cover by low evergreen plants. measured in Daubenmire
cover class means.
terrestrial versus aquatic. terrestrial 1, aquatic 0
SIGNIFICANCE OF VARIABLES
PARTIAL F VALUES DF = 8/34I
XI F = 202.94 p O.OI
x2 F = 23.3I p O.OI
x3 F = 13.53 p O.OI
MULTIPLE REGRESSION
R = 70.06 DF 34I p 0.01
BL-D-132 A - 6
ANALYSIS OF VARIANCE
SOURCE
REGRESSION
RESIDUAL
TOTAL
BL-D-132
DF
8
341
349
ss
21.86
22.68
44.54
A - 7
MS
2.73
0.07
F
41.05
p
0.01
TRUMPETER SWAN
DENSITY= [(1.0974X1) + (0.2869X 2 ) + (-0.554X3 )]/1000
VARIABLES
shoreline development indes. = shoreline length/the
circumference of a circle with the same area as the lake.
x2 presence of open water (absence of ice). no water (X 2 =0)
waterice-covered for more than two weeks of the year (x2 = 1)
water ice-free all year (X 2 = 2)
x 3 presence of emergent vegetation. note present (x3 = 0)
present (X 3 = 1)
SIGNIFICANCE OF VARIABLES
PARTIAL F VALUES DF = 4/345
x1 F = 1113.47 p 0.01
x2 F 19.78 p 0.01
x3 F = 135. 11 p 0.01
MULTIPLE REGRESSION COEFICIENT
R 94.54 DF = 345 p 0.01
BL-D-132 A-8
ANALYSIS OF VARIANCE
SOURCE
REGRESSION
RESIDUAL
TOTAL
BL-D-132
DF
4
345
349
ss
422.67
50.25
472.91
A-9
MS
105.67
0.15
F
725.5
p
0.01
BRADLEY LAKE
STUDY AREA
0 1 -----2
SCALE IN MILES
DINGLE STADT
GLACIER
3
/ ''"'' .· STUDY AREA MAP
\\' '·~··.. FIGURE 1 ~~·" -===~-==---
.. --
'. ,;/
OVERSIZED MAP
NOT 'MICROFILMED
MAP LOCATED IN
ORIGINAL· REPORT
VEGETATION MAP
FIGURE 2 I
! -,
\} '-. ...
BRADLEY LAKE
STUDY AREA
, w .. K/"..
/'.~ ACif t..
(\
: \ \ \
\,
\
\
LEGEND
Density and habitat suitability-
animals J)er square mile/
habitat suitability index
0 2 3.
lii;;;;;i§i5;~~5iii-~
SCALE IN MILES
OINGLESTAOT
GLACIER
KACHEMAK GLAC!ER /
MOOSE
FIGURE 3
0.44/0.79
(\
l \
': \
\
/ NUKA .~
-'Gt.AC\fk;"'
!
LEGEND
Density and habitat suitability-
animals per square mile/
habitat suitability index
,--· ·.,
I
SOALE IN MILES
DINGlfSTAOT
'GlACIER
•
•.t.t:Hf MM. GLACIER
BLACK BEARS
FIGURE 4
I /'; ...
\ \
\"'
BRADLEY LAKE
STUDY AREA
'NUKA /,.
/ ..;: AC'~ ~.'
LEGEND
Density and habitat suitability-
animals per square mile/
habitat suitability index
0 1 ..........._, I
8C~.LE IN MILES
DINGLE STADT
GLIICIER
" . ··._·.
','
. ).·
I
I
MOUNTAIN GOATS
FIGURE 5
BRADLEY LAKE
STUDY AREA
a I
LEGEND
Density and habitat suitability-
birds per square mile/
habitat suitability index
',_ '
~--'
0
W'"'w4MiiiJ
I
SCALE IN MILES
' .... -··
OINGLESTADT
GLACIER
a
KACHEMAK GLAS!ff.' 1
TRUMPETER
SWANS
FIGURE 6
t
I~ HOME! I EI.ECTliiC
I
ASSOCIATION FNTZ a'&K _
IIOl.DOTKA TRAHIIMIS8ION LH;;
I
;'
;
,\
! \ ~,
\ ~ ·--
NUKA RIVER
DIVERSION
0 1
....-....--
2
SCALE IN MILES
·,
('-~ ~-_... i . ·~-~·
'~~ -·~,
'
DINGLfSTAOT
GLACIER
3
NU!-C.t. ------------------------------------------------~~·v·='·":'[R~:--_}~~--------~-PROJECTMAP FIGURE 7 ___ __J
35000
•••ooo i.
= t:
' % HOO
28000
•• 10 ao .40
T .... (YEARS)
-WITHOUT II'IIOaCT
---WITH ltltO ... CT
--MITIGATED L088
'//////, NET L088 OF HA81T~T UNITS
NOTE: L0-8 OU. TO INDIRECT IMPACTS WIU. H III'YIMND 111111 PINAL Dalila.
REMAIIMG L088U DUE TO DIRECT ... ACT8 W&L -atlM,_ 'htROU8ft
~ IIIITIGA,_ IIIUIUM8.
ESTIMATED LOSS OF AVAILABLE MOOSE HABtT AT OVER THE LIFE
OF THE PROJECT.
FIGURE 8
________________ .....
tO 1'0 ao 40
TIME (YEARS)
-WITHOUT .. O .. OT
---WITH NO.aGT
--...,....T.D L088 OR Dlefi'LACEMENT
'IIIII/ •T L_.., AIIIMALI
10
~ .. .........
~-·· ... Mi ..
eo
NOTE: LoeMI-~I!IDIRBOT .. ACT8 wa.L 8E MITteATED DURIIIe FINAL DE .....
ReMA-1101 .. DUE 10 -OT _.ACT8 WILL -MITKIATB) THROUGH
OFF-SITE .rtlM1'10M MilA .....
ESTIMA TEO OISPLACEMENT OR LOSS OF MOOSE OVER THE LIFE OF
THE PROJECT.
FIGURE 9
i ...
4(
t: • I
30000
-W1THOU1' MO.NECT
---WITH NOaCT
--..... ATED L088
1////11 .-T &.ef8 OF tMefTAT UIIIT8
ltOTE:
-tnlll I
ESTIMAJiQ~LOSS OF AVAILABLE BLACK BEAR HABITAT OVER
THE Llt=E OF THE PROJECT.
FIGURE 10
'
J
• .... ..:
:I z c
lA.
0
a: • II
0 ao 40
TIME (YEARS)
WITHOUT PRO ... CT
WITH PWO.MCT
lllfT .. ATD L088 OR DJattLACEMENT
1////// ... T LMe Otr ANIMAL8
50 eo
ESTIMATED DISPLACEMENT OR LOSS OF BLACK BEARS OVER
THE LIFE OF THE PROJECT.
FIGURE 11
' ;
' J
. '
80001-------~----~~-----------------------------
o 10 ao 80 •o eo
TIME (YEARS)
--WITHOUT PlltO.mCT
---WITH PROMCT
--MITIGAT.D L088
1////// MT LOM OF HABITAT UNITS
NOTE: L~ M Tt) ...,IRECT ... ACT8 -.a. 111! .. 118ATED DUll .. PINAL DE81M.
REllA ..... Utel. DU. TO OIRIICT ~T8 W1.L BE MITIUT8D THROUGH
<WF-811W wt't8ATION MeA ... S.
ESTIMATED LOSS OF AVA.ILABLE MOUNTAIN GOAT HABITAT OVER
THE LIFE OF THE PROJECT.
FIGURE 12
• ·~ c
:1 z <
-~
I
I
2.
ORLOea ..
'TOIIID._,
... ACJa,
20~------~------~------~------~------~----~
0 10 20 ao 40 10 eo
TIME (YEARS)
-WITHOUT PMMCT
---WITH PRO.IeOT
--MITteAftD LM8 OR DI8PLACEMENT
'IIIII! -T LMe .. A ... AL8
NOTE: LOa•e DUI N _,IRECT _.ACTS .._L 8E lllfTHIAT.D DU-8 'INAL OE8 ....
AEIIM··· ...... DUa TO etitKT IIIPACft-.&.-M11'18AftD THROUGH
OFF-alTa .fJSA'hON MIIA .... a.
ESTIMATED DISPLACEMENT OR LOSS OF MOUNTAIN GOATS OVER
THE LIFE OF THE PROJECT.
FIGURE 13
• !: z :::. ... c
!:
ID c z
•
7
DI8PI..ACIDeiT OR L088 ·oue TO DMCT IMPA~T8
7000,1-------~------~----~~----~------~------~
0 10 n ao 40 10 10
TIME (YEARS).
-WITHOUT PRO.IECT
---WITH PRO..tECT
--MITIGATED LOSS
111111/ N•T LO .. OF HABITAT UNITS
NOTE: LO-S OtM TO INDIRECT tMPACT8 W&L aE IIITICIATED DUWIHCI FINAL DE .....
......... L088&8 D .. lO DNCT ~T8 waL BE MITIUTED THROUGH
OFF-Sm .-nctATION .. Aa~Rea.
ESTIMA TEO LOSS OF AVAILABLE TRUMPETER SWAN HABITAT OVER
THE LIFE OF THE PROJECT.
FIGURE 14
I • ..
0 • i
38
------------------
.18.~,-------T------~------~------,-------~----~ •• 10
WITHOUT NOoii!CT
WITH PRO.IeCT
20 ,30 40
TIME (YEARS)
IIHT .. ATU LO .. OR DISPLACEMENT
'IIIII/, _,. L ... OP HID8
so eo
NOTE: a.oeaaa DUa TO INDIRECT IMPACT8 WtU. H MITIGATED DURING FINAL H ......
---...... OW TO D ... CT ~ WILL BE MITIGATED THROUGH
OPF-atn 1i11111'1GATION .. AeuRE8.
ESTIMATED DISPLACEMENT OR LOSS OF TRUMPETER SWANS OVER
THE LIFE OF THE PROJECT.
FIGURE 15
\