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SUSITNA HYOOOELECTRIC PROJECT
ENVI RCN-£NT AL Sl1ID I ES
~ES r-IANUAL
SUBTASK 7.11
WILDLIFE ECOL..CGY-
BIG GA'£ Irf>ACT ASSESseiT
AND MITIGATION PLANNING
Tettelltial
I nvitonmenlal
Jpeciali1l1, Inc.
? -------
PLASKA PMR Al1'rlm ITY
SUS ITNA HYmOELECTR I C PROJECT
ENV IRaftENT"Al STIJD I ES
~ES I'WU.IAL
SUBTASK 7.11
WILDUFE . Ecoux;v-
BIG GNo£ I~ACT ASSEsseiT
AND MITIGATION PLANNING
Submitted by
Terrestrial F.nvironmer,tal Specialists , Inc .
to
Acres AIIErican, Inc.
Enviro11IJEntal Stu
Grouo Leader (TES)
July 1980
Copy No . l b __...;; __
ctor (TES)
This procedures manual is a controlled document. Each copy is
numbered and issued i n trust to an individual whose name is
recorded on a distribution log maintained by Terrestrial
Environmental Specialists, Inc., in Phoenix, New York. Amendments
to this document, as they are issued, will be sent to the
authorized holder of each copy. Upon completion of the project
(or by December 31, 1982) all copies of the manual are to be
returned to Terrestrial Environmental Specialists , Inc.
Table of Contents
I.
IMPJI.CT ASSESSMENr
MITIGAT!al PLAN
II. TEX:RNICAL PRX:EI:XJRES •
IMPACI' A.5SE5SMENl'
l!pper Susi tna Basin
oirectimpacts
~s.
Borrow Areas
Transmission Line and Access Roads
Hlll\an Activity
Iooirect ~cts • •
Den site D1sturbance
Alteration of llbose Habitat •
A! teratia) of Carib:>u r-t:>vement Patterns •
Il!pacts on Cotmuni ~ I?ynanics .
llbose-Habi tat Dynamics • . •
Predator-Prey Dynamics
lower Susitna Basin
MITIGA.TIOO PLAN
General ~ch • .
Identificat1on and Classification of ~cts
Analysis of Mitigation Alternatives
Avoidable Impacts •
Unavoidable rmpacts •
Reccmneooations •
III. DATA PIO:EOORES •
IV. QUALIT'! CCNl'roL •
v.
VI. PEPS:NNEL •
1
2
2
5
5
5
6
6
7
7
7
8
8
8
9
9
10
10
10
10
10
11
11
11
13
List of Figures
Figure 1. Potential avenues of i..rrpact en big game soecies in the ~r
Susi tna Bas in.
Figure 2 . Big game i.n'pact assessment .:rd mitigation plan ~paration
schedule.
One of the ncs'C iflt:lortant aspects of the Susi tna Hydroelectric
Studies is the assessment of likely i~cts en big game species that
currently use p:>rticns of the Susitna drainage. Big game anirrals are
very irrp:>rtant to the Alaskan lifestyle and ecoromy. '!hey provide food
for nany state residents, support a consi~rable sport tunting economy,
and are an integral ~nent in the ability of the state to attract
tourists. 'Ihese factors are magnified en this pro~'i!Ct due to the
locatien of the Susitna area between Fairbanks e-nd Anchorage, the
population centers of the st.:lte.
IMPACr ASSESSMENI'
'!he general oojecti ve of this assessment is to predict the nature
and magnitude of inpacts that the prop:>sed Susitna Proj ect may have en
seven big game species. '!he ~ies to be considered are: moose
(Alces alces ), carioou (Rangifer tarandus ), t.ir!t>er wolf (canis ~),
black bear (Ursus cnericanus), brOWri/grizzly bear (Ursus arctos),
wolverine (G.J.lo gulo), and Dall sheep (Ollis dalli ). Each of these
species will be considered in the analysis of the ~tream study area,
which is defined as that p:>rtioo of the Susitna Basin upstream fran the
prop:lsed Devils canycn dam . Downstream fran the Devils canycn dam the
type of inpact will be considerably different. Here , considerations
will focus oo possible ~cts oo rroose wintering areas along the river
to a~ximately the Delta Islands.
Following the preparation of an ~ct assessment, a detailed
mitigatien plan will be prepared. ~ring Phase I (pre-license
application) this plan will consist primarily o f an analysis and
comparison of feasible mitigatioo alternatives . Recommendations will
be made concerning the best app1:0ach to mitioatien including the type
of mitigatien to be undertaken, the land a r ea to be used , and the type
of research to be conducted dur ing Phase II (p:>St-lieense application).
Phase II research will focus upa1 i nformatien needed prior to actual
i.npl ementation of the plan.
II • TEX:HNICAL PRXEOORES
'nle big game irrpact assessment will be based oo data collected by
the Alaska Department of Fish and Game (ADF&G), Acres sul:x:ontractors,
TES subcontractor s, wildlife liter ature, and the exper ience of the
author m other .:onsultants. Details concerning the collection of the
data to be used can be fourd in the specific plans of study and/or
procedures manuals for ADF&G Big Game Studies, Plant Ecology Studies,
Furbearer Ecology Studies , Hydrology, and Design Developnent.
r.:wer Susi tna Basin
In order to determine the ~ct of the Susitna Proj ect oo big
game species in the Upper Susitna Basin (a.t:x:7ve Devils Canyon ), it will
first be necessary to identify the habitat/species relationships that
are operative, predict inpacts oo a::xttX>Oents of the system, and then
predict what changes impacts oo system components will have on the
entire system . Figure 1 was prepared to illustrate the major
o::mp::ments of the system aro the rrost likely pathways of impact that
could occur throughout the system.
The following discussion is based on Figure 1 and is divided into
sections concerning direct impacts, indirect impacts , aro impacts oo
o::mnuni t:y dynamics. The discussion of impacts oo conmuni ty dynamics
surmarizes the flow of direct aro indirect impacts througoout the
components of the habitat/big game community.
Direct Impacts
Direct Lmpacts may originate ~ the following four components of
the project: the impoundments, the torrow areas, the transmissioo line
and access roads, and increased human activity associated with the
constructioo aro operatioo of the facility . "As illustrated in Figure 1 ,
one or rrore of these four aspects of the project may directly i.moact
rroose habitat , den sites , bear f.Op.llations , 'NC>lf f.Op.llatio~c;, Dall sheep
f.Opulations, and caritou rroverrent patterns. This is rot to irrply that
an illustrated impact will necessarily occur, nor does it infer the
extent or ultimate in;>ortance of a specific line of ~ct. Figure
sinply identifies, for consideration, f.X)tential ;>· •• :mues of impact.
Irrpoundmen ts
The creation of ~ large ~undments will result in the
eliminatioo of a presently unlm:lwn quantity of key wintering habitat for
JTOOse. This is especially true in respect to the Watana imp:)undment
which will inundate a large area including a portion of the Wa tana Creek
drainage, an area which has already been identified as a key wintering
area for rroose.
The elimination of moose wintering habitat will ~ly be the
rrost i!T'Ip)rtant big garre impact associated with the project . Figure 1 ,
shows that many components of the system can be affected by changes in
the rroose f.Op.llation . In turn, the factor rrost likely to affect the
JTOOse f.Op.llation is an alteration of habitat . Fortunately this aspect
of the project will be the easiest to quantify aro thus the
identification of direct Unpact oo moose habitat will be quite
reliable.
The determination of impact on moose habitat will be based oo the
following information: 1) the locaticn of key wintering areas for IOCXJSe,
(data supplied by ADF&G); 2) the distribution , acreage , and condition of
key plant corrrnuni ty types (data supplied by Sub task 7 . 12) ; and 3) the
extent of inundation (data supplied by Acres). The vegetation
assessment (Subtask 7 . 12), in conjuncticn with a delineation of the
imp:)undment zone , will enable the determination of h:::>w much moose
habitat will be eliminated. Not all of the habitat outlined by the
vegetation assessment may necessarily be available to ITO')Se, due to
factors such as SI'X)Iol depth. Therefore, aerial survey data from ADF&G,
as well as snow course data from R&M, will be factored in to define ...nat
porticn of each plant community is actually available and used by
JTOOse.
2
TRANSMISSION
LINE &
ACCESS ROADS
IMPOUNDMENT
BORROW
AREAS
HUMAN
ACTIVITY
DEN SITE
DISTURBANCE
ALTERATION
OF MOOSE
HABITAT
ALTERATION
Of CARIBOU
MOVEMENT
PATTERNS
I
\
I
---
PLANT REMAINING
SUCCESSION -/ MOOSE
TRENDS HABITAT
' \.
' '---~--~//
/
' MOOSE \ .....
--\---, POPULATION
~~ «' \~ II\ ~~1-\11 \
\
~1-__ .__ _ __,
BEAR
POPULATION
-_,
WOLF
POPULATION
I
I
-. .j
I ''
I r ---
,I/
CAR IBOU
POPULATION
FIGURE 1. POTENT IA L AVENUES OF IMPACT ON BIG GAME SPEC IES IN TIE UPPER SuS ITNA BAS IN.
I
I
I
I
--DIRECT
IMPACT
INDIRECT
IMPACT
-l SC AVENGERS : 1 ',
I
-1---'
I _--1
I
I
I
I
I
I
I
I
,I
-;,
WOLVERINE &
RE O FOX
OALL SHEEP
POPULATION
A secorrl type of i.rrpact that could result fran the creatien of the
two inp)urrlnents is the immdation of den sites. This is especially
i.np:>rtant in regard to wolf dens, which are often use:i year after year
and the loss of ...tlich nay result in abancbnment of an established
territory by a pack. Since many wolf dens are created by enlarging
e.xisting red fox dens, i t will be inp:>rtant to also consider the
eliminatien of existin; fox dens, or suitable fox denniJ'l3 areas, which
oould represent future sources of new denning opportunities for wolves.
The i.rrpact of inundatien en wolf dens will be determined by mapping
the location of krown wolf de.ns, as determined by radio telemetry (by
ADF&G), in relatien to the projected inp:>unanent zone. Likewise, maps
of existing red fox dens, as well as sui table areas for denning, will be
mapped to determine the relative loss of potential denning
opportunities.
There is also the possibility of ~cting suitable bear denning
areas. Although bears are not as limited as wolves as to availability
4
of sui table den sites, certain types of areas may be pr-eferred, oc required,
and loss of such areas could cause a subsequent i.rrpact to occur. Since rost
brown/grizzly bears den at altitudes higher than the proposed in'p:>l..lrdnent,
it is unlikely their densities will be affected by this aspect of the
project. Black bears, en the other hand, may use areas within the
i.np:>unctnent zone foc dennil'l3 and therefore are rore likely to be affected.
Data fran radio-rollared bears will be used by ADF&G to establish locations
of dens during the winter of 198Q-81 and 1981-82. 'lbis, in axti>inatien with
literature oo black bear denninq characteristics, vegetation rraps arx3
to{:Ographic maps, will serve as the tool for predictin; i.rrpact en this
inp::lrtant aspect of black bear ecology.
One of the rost controversial questiollS associated with the
Susitna Project concerns the to55ible disruption of migration p3tterns
of the Nelch.\na caril:xx.l herd. The upper reaches of the Watana
.iJrq;x:>uncinet may intersect a route ...tlich is reported to be pt"esently
use:i for rovement to and fran a calving area south of the Susitna
River in the vicinity of Kosina Creek. Several questions I'IIJSt be
answered before a predictioo can be made concerning the impact oo caribou
ITOVements.
The key problem ooncerns difficulties in predicting caribou
behavior. It is anticipated that through aerial surveys and radio
telemetry data, ADF&G will d:>cunent the current novement p3tterns of the
Nelchina herd and suwlement that data with historical information.
fbwever, it will be very difficult to pr-edict future novement p!ltterns.
caril:xx.l behavior is a little understood phen::xneral and ant prediction
will have to be t.ent:>ered with appropriate cpal.ifications.
Followi.n; the determinatien of current migratioo routes, the
critical aspect of the caribou {X'Oblem is the condition of the
irrp:>urdnent at the tine of the year when they rnt!tJ at~ to cross it.
It is to55ible that the pr-edicted winter dra\od:Ml nay create conditions
such as ice-shelving, nu:3 banks, cr nu:3 banks oovered with extensive
blocks of ice of various thicknesses. Factoring in such variables as
bank to{:Ography and timin:J of migration, it will first be necessary to
determine what types of conditions the caribou will face if they oontinue
to cross the Susitna in the i..Jrpxlrdnent zone. 'lbis informatien will be
provided by Peres and R&M. 'lllen the rore speculative task of predicting
the behavioral re~ of c:aritx:>u to those ronditions nust be dealt
with. Although sare research has beEn done concerni!'l:3 caribou response
to the Trans-Alaska Pipeline, it nay rot apply to the oonditions in this
case.
5
In 5U11"Mr'Y of the c:arioou ~lem, sufficient data will be available
to describe the current s ituation . Data srould be available fran the
engineering and hydrology disciplines to enable a Ff:ediction o f
conditions that caribou face if they are still crossirY:l the Susi tna River
in the 2Dle of the pt'Op:)Sed ~ts. A Ff:ediction o f c:aritx>u
reS(XXlSE! to these conditions will be speculative but will be base::) en all
available literature and scientific opinion .
Borrow Areas
The use of certain ron-~t l.aOO for the acquisition o f
constructiO'I materials (borrow areas ) will result in disturbance and
elimination of s::xne big game habitat. The t:lo() likely in{lacts o f torrow
areas are further' eliminaticn of rocose habitat, and I=OSSible disturbance
of den sites for ...:>lves and bears. The same approach to identifying
these tw:> areas o f ~ct will be followed as previously discussee for
~t-related ~cts.
Transnission Line and Access lh!ds
It is ~ticipated that the nDSt lik,dy iJTpact of the CDOStruction
arx3 operatiO'I of the transmissicn line and access roads will be 0'1 the
disturbance of den sites a-.d alteration of caribou rrovement t:atterns.
In this case, it is rore likely that disturbance of den sites will
result from the fl['esence and use of the transmissicn line and road,
rather than habitat t'E!!TDVal as would OC'Ct1r in the case of the
~ts and to-crow areas. 'llle pr-ocedure to be used in Ff:ed i.cting
~ct in this case will ronsist of first ~riog the locatiO'I of the
line and road in relationship to krown ...:>1 f dens and territories, as
well as areas determined to be suitable fat" bear denning. Scientific
literature and the experience of researchers in simi liar situations
will then be used in o rder to generate a predicticn ooncerni!'l:3 likely
i.rrpacts.
'nle fl['ediction of ~ct 0'1 carioou ncvement is also different
than that discussed in regard to the in'pxudnents. Although the
problem of predicting caribou behavior remains the same, the
transmissicn line and access road represent unnatural structures to the
caritx>u. 'lllerefore, experience gained through research and corrparable
problems alon:J the Trans-Alaska Pipeline may prove of use in this c..1Se .
Aqain, data provided by ADF&G concerning carioou mi<;ration routes and
calviog areas will be mapped in relaticn to the access road arx3
transmission line routes.
Hunan Acti vi tv
Predictiog the inpact o f increased tunan activity 0'1 big game
speci es will probably be the rrost subj ective I=Orticn of the big game
inpact assessment. Although s.Jfficient data will exist to enable
o::mparing areas of various degrees of hl.IT\al'\ activity to key behavioral
and habitat parameters of the big game populations, it will be
difficult to project behavioral resp:>nses with the same degree of
accuracy as with ~ other i.np!cts. HLIT\an activity will include both
constructioo and operatioo activities, including the presence of people
aroun:i ~. construction sites, traffic oo the access roads, and all
air traffic associated with the project.
'lhe i.Jypact analysis will consider the direct i.np!ct of tunan
activities oo den sites, caril:::a.l rmvement patterns, wolf pop..~lations,
bear p:::lplllations, and Dall sheep populations. 'lhis will be
acconplished by mapping loci of hlJnan activity and ranking then in
order of intensity and dlration. 'Ibis will then illustrate the
juxtapositioo of various levels of activity to carib::lu migration
routes, \ooOlf dens, key bear foraging areas, etc. As a result i t will
be possible to determine, oo a relative basis, where and in regard to
which species, the i.np!ct of tunan activity is rrost likely to occur .
As in some other areas of concern, informatioo gathered during the
oonstruction and operation of the Trans-Alaska Pipeline will be
consul ted and may prove useful in predicting behavioral resp:>nses to
this aspect of the project.
'11le Susitna Project may result in an increased utilization of the
Upper Basin by sp:>rt hunters . '!he extent o f change will deper¥:3 to a
large extent oo \olhether or rot the access road is cpeued to the p.lblic .
'!be big game inpact assessment will consider th.i3 potential chan<;Je and
project ~t effect it will have oo big game pop.1lations. Although
this aspect of the project could have a significant effect, the impact
can be mitigated, if deemed necessary, by alterinq the game regulations.
Indirect llrpacts
Following the determination of direct project i.np!cts oo den
sites, JroOse habitat, caribxl rovement patterns, wolf, bear and sheep
pop.Jlations, the process will be carried ooe step further to determine
indirect inpacts. As illustrated oo Figure 1, there is some overlap
where both direct and indirect inpacts may be operative. 'lbe following
discussioo concerns the prime avenues of indirect in"pact including
inpacts of den site disturbance oo \ooOlf and bear pop..~ lations, impact of
rooose habitat alteraticn en l'lkX)se populations, and impact of alteration
of carilx>u rTOVement patterns oo caribou p:>pulations.
Den Site Disturbance
The distutbance of den sites through either increased human
activity, inundation, or borrort areas, could result in changes in the
pop.Jlation of wolves and bears. Currently used wolf dens and bear
denning areas, particularly tl'x:>se of black bears, will be mapped and
carpared to areas to be inundated and centers of tunan activity.
'!be degree to which wolf and bear pop..~lations may change as a
result of den disturbance will be difficult to determine. It will
depend to a great degree oo the availability of alternative dens or
areas suitable for denning. It is anticipated that sufficient data
will be gathered ':/j ADF&G concerning the physical characteristics of
den sit.es, associated territories, and forag i ng areas to treciict the
relative extent of inpact oo wolf packs and black bears.
6
Alteration of Moose Habitat
'Itle nost in'portant aspect of altering I!'OOse habitat will be the
reduction o f key wintering areas . 'Itlis, in turn, could cause a
decrease in the noose p:JpUlation in nuch of the UJ?Per Susitna Basin.
OJri.ng Phase I it will be p:>ssible to determine tre relative percentage
of noose winter habitat that will be lost. Phase II studies will
include a detailed analysis of browse quantity an:3 quality an:3 will
thus enable a refinement of the net loss of noose winter habitat.
In a general manner, as previously described, it will be p:>ssible
to pt"edict the extent of reduction in the capacity of the habitat to
support IT'OOse p:>pulations in winter. 'lb a~lish this will entail
C'Ort'parinq rot only the area of habitat loss, but aloo its relative use
to var ioLIS subp:>pulations of IT'OOse . Population data will be collected
by ADF&G in the form of aerial surveys and radio telemetry studies .
The mapping an:3 quantification of p:>pulat ion an:3 habitat data will
enable the iden tification of those subpopulations which will be
i.rrpacted, an:3 tre degree of iJ'Il)act. 'Itlis will be expressed as number
of noose that can be supported, as well as the availability of
alternative wintering areas.
Alteration of caribou z.blfenent Patterns
The iJTpact oo IX>Pllations of alterirJ3 JlDV'ement patterns of caribou
will be nore difficult to assess than the ~ of habitat alteration
oo IT'OOse p:>pulations because tre former indirect iJTpact can take tre
form o f either a change in caribou utilization of the UJ?Per Susitna
Basin, or a chan9e in tre total herd size, or a <Dtbination of both.
The assessment of the caribou inpacts will be based oo aerial surveys
an:3 radio telemetry data which will identify current migration routes,
the timing of novements, and habitat needs. These data will be mapped
in corttlarisal to project aspects such as i.np:lunanent bc::x.Jr¥::!aries, access
roads , transmission lines, and centers of tunan activity. A key factor
in determinir¥3 tre extent of iJTpact on caribou populations will be the
description of ice and water oonditions at likely crossing p::>ints. The
ultimate prediction of inp3ct on t:r.e Nelchina herd will have to be
subjective , but will utilize all available data, literature, and
scientific opinion.
~cts on catmunity Dynamics
The big game a::mrunity in the UJ?Per Susitna Basin is a dynamic
system . 3pecies are constantly interacting with habitat corrp:>nents and
other species . As a result, any inpact, either direct ()[' indirect as
illustrated on Figure 1 , may affect sane ()[' all oorrpxlents of tre system .
Therefore, the final i.rrpact analysis will attenpt, by using the pr-e-
viously described direct an:3 indirect iJTpact predictions as tools, to
describe the total chan<Je in the big game oonmmity that will take pla~
7
as a result of the Susit."'la Project. 'Itlis will require a thoro~ consider-
ation of key oormunity relationships. Figure 1 sbJws that the relationship
between IT'OOse populations an:3 IT'005e habitat is critical to tre entire
system. Likewise the predator-prey dynamics involvinq bears, wolves,
IT'OOSe, and caribou are of pararoount i..rttX>rtance. '!be followirJ3 is a general
description of l1:Jw these factors will be analyzed. A detailed discussion
is oot included at this time since many specifics of tre approach will
require 9:me baseline data before techniques can be selected .
8
lb:>se-Habi tat Dynamics
Any alteration of ncose habitat will result in s:me level of impact
on the Susitna rroose p:>p.llation. This , in turn, wi ll alter the
interrelationship bebleen the noose popu lation and the remaining
available habitat . As stated previously, sufficient data will be
gathered fran the vegetation analysis and rrcx:>se p:>pulation studies to
determine the ano.mt of winter habitat ret011ed an:3 the anount remaining .
It can be assuned that additional browsing rressure will then be ~li ed
by the ll'OOSe on the re!llai.nin; habitat. It will therefore be necessary t:>
det:ermine row 111Jdl browsing pressure the remaining habitat can 9.lpf!Ort.
This will be done usinj data on the rroose p:>p.llation , the general anount
o f habitat resraining, the plant successional trends that are operative ,
and the current corxHtion of browse in the remaini~ area.
Predato r-Prey Dynamics
The f i nal analysis, based upoo ~1 [receding considerations , will
assess the p:>ssible alteration of predator-prey dynamics in the tJF:per
Susitna Basin. !he key rredator-prey relationship is between noose and
~lves, with carirou and 1o10lves beinj a 5eCOOOary relationship. Bear
predation on m:x:>se calves will also be considered in the analysis.
As illustrated in Figure 1, the relationship betweEn rrost predator
and ;rey species is a ~ relationship. '!his is especially true ir
regard to 1o10lves ~ on rroose, caribou, an:3 sheep. 'nle abundance c ·f
all <r any of these prey species will affect the l"l.JJt)er o f 1o10lves that
the area can support. Likewise the nl..lnber o f 1o10lves in an area can,
under certain circunstances, affect the density of 01e or all o f t!"lese
prey species. 'therefore, a:trf chanqe in either 1o10lf nlltbers or prey
nt.l!t)ers as a result o f the {X'Oject can result in a shift in JX'edaticn
pressure and subsequent changes in the nuroers of o ther species. By
using data concerning direct and indirect inpicts as previously
discussed, especially ~cts on rroose, an analysis will be conducted tc
determine p:>SSible ramifications to the big game pt:'edator-prey system.
Lower Susi tna Basin
!he big game in"pact assessment concerning the area d::>wnstream from
the Devils Canyoo dam to the Delta Islands will be directed at
determining what effect an alteration of flow regimes will have :n
rroose habitat and subsequently on rroose [X){:Ulations that winter along
the lower Susitna. The major avenue o f irrpact that could occur in t.'1e
downstream area is a change of rroose habitat resulting fran tx:>th annual
and lonq-term chanqes in the flow regime o f the river. Data fran a
variety of studies will be required to assess the ~cts on rroose.
I t is currently felt that noose nove into the riparian zooe along
the lower Susitna durinj the winter and feed on browse species on
islands and the flood plain imnediately adjacent to the ri vt"r. 'Ib
determine the extent of USQ by rroose, ADF&G will conduct aerial surveys
during the winter ncnths and also nonitor radio-collared noose year
round. '!his will enable the identification o f key wintering areas
along the nver, as well as determine the extent o f p:>SS ible inpact on
JroOSe for a a::.:\siderable distance on tx:>th sides o f the river.
9
Both ADF&G and TES subcontractors will assess the general status
of rroose trowse along the river during Phase I • A more detailed browse
study, incltxling data en quantity, quality, availability, and
utilization will be performed during Phase II . The Phase I data will
enable a general assessnent of the quality of rooose habitat and, in
ront>ination with rroose ;opulation data, allow fbr the identification of
critical wintering areas.
'lb utilize this information in a pt"edicti ve fashion, Phase I
stooies to be c:oOOucted by TES subcontractors will attempt to gain an
understarding of plant succession trerds along the river. Since it is
likely that the key factor affecting the successicn process is periodic
flooding, the validity of the entire i..npact assessment will depend oo
predicting changes in the hydrology of the lower Susitna. A descritr
tion of likely changes in river hydrology cn:l resulting changes in
river rroqtx:>logy will be provided by R&M. By l.ll'lderstarding both annual
and long-term hydrologic parameters it will be IDSSible to generate a
predicticn of hoi the riparian areas and thus plant succession trends
may be altered by the Susitna Project. 'Illese factors directly
influence rooose EXJp.llations over a very large area alon; the lower
Susi tna Valley.
MITIGATICN PLAN
General Appr"oach
The mitigation plan will be based on the inpact assessment as
previously described. An att.e!\'q?t will be made to develop a mitigation
plan taking into ronsideration rot ally species-specific inpacts oot
aloo the i..Jrpacts oo corrmmi.ty relationships .
'lb assure that all mitigation alternatives ace mroughly
considered and developed, a mitigatioo team will be created . 'Ille
following TES personnel or subcontractors will ~se the ~oa:king
core of the mitigatioo team. Mr. Edward T. F.ee:3 (TES), Wildlife
Ecology Group Leader, will function as team roordinator. Mr. Reed
will work closely with Mr. Jose,;:t~ M. McMullen (TES), Plant Ecology
Group Leac"er, Mr. William Collins, Plant Ecology In~tigator
(University of Alaska), and the big gane expert wtD \nil perform the
i..npact assessment. In addition, it is suggested that at least ooe
representative fran the following organizations serve oo the mitigation
team: Alaska Power Authority, Acres ltnerican, Inc., Alaska Department
of Fish and Game, United States Fish ard Wildlife Service, United
States Bureau of Land Management, and Cook Inlet Region Inoorporated.
pt)st of the pl~ and developnent work associated with this
task will be performed by the rore rnestbers of the team. Prio r to the
<XlmTlerlC."emnt of actual planning, inp.Jt will be solicited fran other
team rnestbers in order to a::xrpile specific roncerns, opinions,
suggestions, and philosophies. It is anticipated that a series of
progress meetings will be held througoout the mitigation planning
process in order to brief tean lt'lelltlers oo the status of the effort and
to pr:esent q:p:>rtuni ties for discussion and group decision rraking
concerning key issues and problems.
10
Identification and Classification of ImpaCts
'Ihe first step in the pr:eparation of a miti gation plan will be a
thorough review of the inpact analysis. OJring t:J1 is review, impacts
will be grouped into two catc;pries: irrpacts that may be avoided or
minimized by alteration of project design and operation, and
unavoidable ~cts. In each case information identifying the nature
of the i.Jrpact, species, and land area involved will be analyzed. Then
a list of feasible mitigation alternatives will be developed and
analyzed.
Analysis of Mitigation Alternatives
Avoidable Impacts
Detailed consideration will be given to means of avoiding ~cts.
Depending on the nature of the inpact, a variety of actions can be
recomnended. Aspects of the Susitna Project that will be considered
include, but are not limited to: extent of the impoundment zone,
alteration of <Dwnstream flow regimes, location of access roads ard
transmissioo line, and timing of certain co;1Struction and operation
activities. The analysis of such alternatives will require input fran
Acres engineers .
Unavoidable rmpacts
This portion of the effort will consider mitigation alternatives
that could be irrplemented to compensate for unavoidable impacts on big
game poPJlations. Again the irrpact assessment will provide rrost of the
data necessary to accomplish this analysis. 'll1e ultimate goal of this
effort wi ll be to develop a big game management program that will
either allow for the maintenance of existing poPJlations or the
enhancenent of other p::>{:Ulations tn the extent necessary to offset
project-related l osses.
'Ihe analysis will consist of three major p,:1rts: management q:>tions
that can be irrplemented, availability of suitable land areas and the
legal feasibility of executing management q:>tions, and final! y, the
pt:ojected cost of implementing the mitigation plan.
One cpestion to be answered is whether or rot there is sufficient
land of a suitable nature available within the ~r Susitna Basin to
manage for increased big game populations. If rot, it Wl.~
necessary to identify alternative areas where poPJlations can be
enhanced through management pr:acti1::es. This will require an
investigatioo of both present habitat coroitions, garre FOPJlations,
land ownership,·and associated regulations governing the use of sur.h
land.
Reccmnendations
The end ~uct of the Phase I mitigation planning will be a
recomnended plan of mitigation . This will probably be a general
11
plan outlinir¥J the rost pran:isi.n:J 1'1'1ana9ement o ptions, the best larrl
area to be used, and an estimate o f mitigation oosts. It is tnlikely,
due to the loog-term studies beil'¥3 conducted by ADF&G, that sufficient
data will be available prior to license application to develop a plan
that can be executed. !be rea:mnende:'i plan will require refinement as
additional data are received. 'ntis is especially true c:onceming
detailed moose habitat data, which is a Phase II effort . Included i n
the Phase I effort will als:> be recomneudations identifying additional
research that will have to be conducted in order to fine tune the
mitigation plan to the ~int where the maxi.nun benefit will be realized
fran its inplementation.
III. DATA PRX:mJRES
'!here will not be ant data collected directly by invest igators
working oo the big game i.nplct assessment and mitigat.ion plan. All
data used in this assessment will be provided by ADF&G I Acres I Acres
subcontractors , and TES sulx:ontractors.
TES will depend oo q.Jality oontrol procedures inplemented by the
collectors of data to be ~ in the big game assessnent. 'nle actual
organization o f data required to produce an ~ assessment will be
ba.s63 to a great de9ree oo the profess1onal opinioo ard philosophy of
the ilrpact investigators. To assure that the i.nt*:t assessment is
thorough ard has adequately addressed all issues and incorporated all
feasible oontingencies, several experts outside of the rxoject team
will be contacted an:! asked to review and comnent oo the impact
assessment and mitigation plan . 'ntis will allow for the review o f all
practical aspects of the situatioo and will avoid the ~ssible problem
of c:onfining the assessment entirely to the expertise and ~inion o f
o ne oc bo indi •riduals.
v. SCHmJLE
!be big game intlact assessment and mitigatioo planniJ'¥3 will be a
continual pt"'CeSS througoout Phase I • Since many aspects of the
analysis are dependent oo receipt of data fran other sources, there
will be an uneven distribution of time spent oo these efforts. Sane
field time will be expended to gain an in-depth familiarity with many
aspects of the species and habitat <D~Tp:l'lents. 'ntis will be necessary
to place data into perspective with all project <XlrllX>nents. Figure 2
is a schedule of activ ities as currently envisioned.
Literature Review
Field Reconnaissance
Coordination Meeting
Impact Assessme nt &
MitiqaLion Plan Prep.
Report Preparation
Report Due to TES
1980 1981 198 2
-=J-:F::-:-cM:-:-A--::M-:-::J:-J A S 0 N D J F M A M J J A S 0 N D JF M A MJ
X X X X X X X X X
X X X X X
X X X
X X X X X X
X X X X
X X
Figure 2. Big game impact assessment and mitigation plan preparation
schedule .
13
VI. PERS:HlEL
The following key persoonel will be involved in the preparation o f
the ilrpact assessment an:3 mitigatioo plan. Additional external review
experts will be CDnSulted at a later date.
Edward T. Reed -Wildlife Ea:>logy Group Leader, TES; several
years experience in assessing proj ect ~
oo wildlife pop.Llations and ccxm:Hnatioo o f
study efforts.
Josept M. McMullen -Plant Ecology Group Leader, TES; several
years experience in vegetation analysis Cl'ld
ronmmi cy successioo process.
William Co llins -
Irtp!ct Expert -
Plant Ecology Investigator, University of
Alaska Agricultural Experiment Station;
thorough familiarity with big game habitat
analysis procedures.
'lb be selected by Septe!Tt:ler 1 , 1980;
extensive experience with big game species
and habitat in subarctic regions .