p. 1 r 5. 0 Impingemen t Effect s

20 0 18 0 16 0 H 

### ?14 0 o = 12 0 I Stat e Tota l I Montere y Are a

198 6 198 7 198 8 198 9 199 0 199 1 199 2 199 3 199 4 199 5 199 6 199 7 199 8 Source: CDFGLandings Summaries 1986-1998. Figur e 5-5 . Commercia

l marke t squidlanding s reported fo

r Californi aan

d Montere y area . Landing s of

squi dca n fluctuat e drastically fro myear to year , but , despit e intens e fishin g pressure , hav e no t

exhibite dastead y declin e tha t woul d indicat e overharves t (Star r e t al. , 1998) . Squi dabundanc e an dharves t i s generall y lo w durin g E l Nin o years , suc h a s 1983/198 4 an d 1998/1999 . In recen t

years , marke t

squi d landing s a

t Montere y are aport s hav e range d fro move r 3 0 millio n pound s durin g apeak year i n 199 4 t o aroun d 185,00 0 pound s durin g 199 8 (CDF G Landin g Summary) . Althoug h subjec t t o thes e great

fluctuations , th e marke t

squi d fishery i s frequentl y amon g th e mos t profitabl e fisherie s i

n th e Montere y Bay area . 

## 5. 3 Impingemen t Effect s Norther n anchov y Engraulis mordax was th e mos t

abundan t fis h specie s collecte d fro mboth intake s an dconstitute d6 1 percen t o f al l fishe s impinged . Shine r perc h Cymatogaster

aggregata ranke d secondi n abundanc e at 9 percent , followe d b y topsmel t Atherinops affinis ( 9 percent ) an d Pacifi c herrin g Clupea pallasi ( 4 percent) . Thes e fou r specie s accounte d for

8 3 percen t

o f al l fishe s impinge ddurin g th e entir e study . Norther n anchov y wa s th e mos t abundantl y impinge d fish fro mbot h intakes . The y wer e impinge din highes t

number s durin g th e summe r an d earl y fall month s an d wer e presen t in ver y lo w number s durin g th e winter . Pea k impingement

occurre d in lat e Augus t

an d earl y Septembe r a t bot h intakes : 19,07 7 a

t Unit s 1 throug h 5 an d 90,16 0 a t Unit s 6 an d 7 . Base d o n laborator y growth rates , i t

wa s surmise dtha t

th e northern anchov y impinge d durin g th e summe r an d fall wer e spawne ddurin g th e previou s spring .

E9-053. 9 5-2 0 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P. 2 

# 1 1 1 w 

# 1 I



# e i i 5. 0 Impingemen t Effects



### Shine r perc h was th e secondmos t

abundan t fish collecte da

t Unit s 1 through 5 (26,000 ) and th e fourt h mos t abundan t a t Unit s 6 an

d7 . The y wer e collecte dthroughout

th e yea r but peake d durin g their

spawnin g perio di

n the sprin g an

dsumme r months . Shine

r perch ar e live-bearer s an dthe majorit

y o f shiner s impingedwer

e young-of-the-year . I

t wa s though

t tha t gravi d female s ma y have prematurely release dthei r embryo s whe

n th e cam e int o contac t wit h th e screens . Topsmel t was th e thir

dmos t abundantl y impinge dfis

h a t Unit s 1 through 5 (13,000 ) an d the second mos t

abundan t a t Unit s 6 an

d7 (16,000) ; overall thi s specie s constitute d8. 8 percen t o f al l fishe s collected . They wer e impingedthroughout

the year , wit

h pea k abundanc e fro

mOctobe r throug h December . Larg e school s o f topsmelt , whic

h ma y have bee n associate dwit

h spawnin g activity , wer

e observe di

n the harbor

durin g th e fal

l an dearly winter . Pacific herrin g was th

e fourt h most abundantl y impingedfis

h an dconstitute d4. 3 percen

t o f al l fishe s impinged . They wer e impingedthroughou

t the yea r wit h pea k densitie s fro

mJun e throug h August , wit

h asecond , lowe

r pea k i n Januar y an dFebruary . Thirtee n specie s o

f surfperc h wer e collecte di

n impingemen

t sample s fro

mth e Unit s 1 throug

h 5 intake , an d1 2 specie s fro

mthe Unit s 6 an

d7intake . Shine

r perc h discusse dabov e was th

e mos t commonl y collecte dspecie s a

t bot h intakes . Othe

r specie s include dwhit

e seaperch , an

d barred , black , dwarf

, kelp , pile , rainbow , rubberlip , silver , spotfin , striped , an dwalley e surfperches . Walley e surfperch wer

e collecte dthroughout

th e year , wit

h pea k number s impinge di

n Jun e an d July . Mos t

wer e impinge d i

n the summe

r an dwer e juveniles . Whit

e seaperch wer

e impinge d als o throughou

t th e yea r wit h peak s i n abundanc e betwee

n Ma y an dJul y andwer

e mainly juveniles . Rockfishe s wer

e represente di

n impingemen

t collection s by atota

l o f 1 4 species . Th e mos t abundan t wer e olive , blue , gras s an

dbrow n rockfish an

dbocaccio . Thes e fiv

e specie s accounte d fo r 8 9 percen t o f al l rockfishe s impinge da

t Unit s 1 throug

h 5 an d8 4 percent

a t Unit s 6 an

d 7 . The percentag e o

f bocaccio , the singl e mos t

abundan t rockfish impinged , a

t Unit s 1 through 5 (5 9 percent) was nearly th e sam e a t Unit s 6 an

d7 (5 3 percent) . Bocacci o wa s impinge d throughout

the year , wit

h th e greates t

abundanc e i

n Ma y throug h September . O n the basi s o

f th e length s o

f impingedbocaccio , i

t was determine dtha

t virtuall y al

l wer e young-of-the-year . Figur

e 5- 6 show s th e mea

n lengt h o f bocacci o collecte di

n impingemen

t sample s a t the Mos s Landin g Powe

r Plan t fo r Unit s 1 throug

h 5 an dUnit s 6 an

d7 intake s (PG&E , 1983) . Th e datashow tha t mea n lengt h ofth e bocacci o measure dwa s les s tha n 18 0 mm , the maximu

mlengt h o f th e young-of-the-yea

r bocacci o (Star

r et al. , 1998) . A par

t o f th e tota l numbe r o f bocacci o i

n th e sampl e wa s measured . The numbe r o f bocacci o measure d durin g eac h mont h i s liste dabov e eac

h o f the figur e bars . Figur

e 5-7 aan d5-7b show th e numbe

r measured vs . tota

l numbe r o f bocacci o collecte di

n th e impingemen

t samples . E9-053. 9 5-2 1 MLP P 316(b ) Resource Assessmen t 4-28-200 0P. 3 p 5. 0 Impingemen t Effects



### Olive/yellowtai l rockfish constitute d1 4 percen t o f th e rockfish collecte dfro

mUnit s 1 through 5 intak e an d1 6 percen

t a t Unit s 6 an

d7 . The y wer e collecte dthroughout

th e yea r wit h pea k abundanc e i

n June an dJuly . Blu e rockfish comprise d6 percen t o f rockfis h collecte da

t Unit s 1 through 5 an

d4 percen t a t Unit s 6 an

d7 . Th e averag e lengt

h fo r the Unit s 1 through 5 was 7 0 m m(2. 8 in. ) an

d6 7 m m(2. 6 in. ) a

t Unit s 6 an

d7 . A s wit

h th e olive/yellowtai l virtually all blu e rockfish impingedwer

e juveniles . Impingemen

t survey s wer

e take n a t th e coolin g wate

r intake s fo r Unit s 1 through 5 an

dUnit s 6 an d7 fro mJanuar y 197 9 to Marc

h 1980 . 25 0 Numbe rof Measurement s Show n Abov e Bar s Unit s 1-5/Units6 , 7 Maximu m Lengt h of Young-of-the-Yea r Bocacci o 18 0 m m 18/6 0 9/1 1

11/1 2 .1/1
. J

Feb-7 9 Mar-7 9 Apr-7 9 May-7 9 Jun-7 9 Jul-7 9 Aug-7 9 Sep-7 9 Oct-7 9 Nov-7 9 Dec-7 9 Jan-8 0 Feb-8 0 Mar-8 0 

### Figur e 5-6 . Mea n lengt h o f bocacci o collecte di n impingemen

t samples a t th e Mos s Landin

g Powe r Plan t fo r Unit s 1 throug h 5 an dUnit s 6 an d7 intakes (PG&E

, 1983) . Figur e 5- 8 show s th e mea

n monthl y concentration s (#/l,00 0 m3 

### ) fo r th e fou r mos t abundantly impinge dfishes : norther

n anchovy , shine

r perch , topsmelt , andPacifi c herring . Th e mea n

E9-053. 9 5-2 2 MLP P 316(b ) Resource Assessmen t 4-28-200 0P. 4

5. 0 Impingemen t Effects
100 0

10 0

o E

Feb-7 9 Mar-7 9 Apr-7 9 May-7 9 Jun-7 9 Jul-7 9 Aug-7 9 Sep-7 9 Oct-7 9 Nov-7 9 Dec-7 9 Jan-8 0 Feb-8 0 Mar-8 0 Figur e 5-7a . Numbe r

measure d vs . tota l numbe r of bocacci o collecte d i

n impingemen t

sample s a

t th e Mos s Landin g Powe r

Plan t Unit s 1 throug h 5 intake s (PG&E , 1983) . 1000 0

100 0

1 100 N o Lengt h Dat a fo rMar-7 9 D Tota l Numbe ri n Sampl e • Numbe rMeasure d

Feb-7 9 Mar-7 9 Apr-7 9 May-7 9 Jun-7 9 Jul-7 9 Aug-7 9 Sep-7 9 Oct-7 9 Nov-7 9 Dec-7 9 Jan-8 0 Feb-8 0 Mar-8 0 Figur e 5-7b . Numbe r

measure d vs . tota l numbe r o f bocacci o collecte d in impingemen t sample s at

th e Mos s Landin g Powe r

Plan t Unit s 6 an d 7 intake s (PG&E , 1983) .

E9-053. 9 5-2 3 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P. 5

5. 0 Impingemen t Effect s 1 0

o o o 4f c 

# ¥ 5 a> E a > E 4 a E B Norther n Anchov y Unit s 1-

5

• • -ShinerSurfperc h Unit s 1- 5 •it - -Topsmel t Unit s 1-

5

• - -Pacifi c Herrin g Unit s 1- 5 - B —Norther n Anchov

y Unit s 6 , 7 0 Shine rSurfperc h Unit s 6 , 7 -t_ —Topsmelt Unit s 6 , 7 - 0 —Pacifi c Herrin g Unit s 6 , 7

*•** •m*+ Jan - Feb - Mar - Apr - May - Jun - Jul - Aug - Sep - Oct - Nov - Dec - Jan - Feb - Mar 7 9 7 9 7 9 7 9 7 9 7 9 7 9 7 9 7 9 7 9 7 9 7 9 8 0 8 0 8 0 Figur e 5-8 . Mea n monthl y concentration s o f th e mos t abundantl y impinge d fishe s at th e Mos s Landin g Powe r Plan t Unit s 1 throug h 5 an d Unit s 6 an d 7 intake s (PG&E , 1983) .

E9-053. 9 5-2 4 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P. 6
5. 0 Impingemen t Effects 

### monthly concentratio n wa s determine db y calculatin g th e mea n concentratio n fo

r all o f the survey s take

n durin g tha

t month . Th e surve

y dataillustrate tha

t th e highes t

impingemen

t fo r th e norther n anchov y occurre ddurin g th e lat

e summe r an dfall . Impingemen

t fo r shiner perch wa s hig h durin g th e summer , wherea s topsmelt experience dth e highes t

impingement

durin g th e late fall . Figure s 5-9 aan

d5-9 b als o show th e mea

n monthl y concentration s fo

r th e abundantly impinge d fishes . Howeve

r i n thes e figures , th e concentratio n fo r eac h o f th e fou r specie s i s presente d i

n on e recor dpe r month . Thi s provide s a

n indicatio n o

f th e tota l impingemen

t fo r al l abundan t fishe s a s wel

l a s the contributio n t

o the tota l b y eac h o f th e fou r species . Thes e figure s furthe r illustrate tha

t th e highes t

concentratio n occur s durin g th e summe r an dfal l seasons . Figure s 5-10 aan

d5-10 b show th e mea n monthly concentration s fo r thre e selecte dcance

r crabs ; Cancer antennarius, Cancer

anthonyi, and

Cancer productus. Thes e figure s show tha t Cancer antennarius experience s the highes t impingement . Cancer

anthonyi ha

dthe nex t highes t impingemen

t level s throughout

the surve y period .

E9-053. 9 5-2 5 MLP P 316(b ) Resource Assessmen t 4-28-200 0P. 7

5. 0 Impingemen t Effect s

E s

a. E • Pacifi c Herrin g Unit s 1- 5 • Topsmel t Unit s 1-

5 • Shine rSurfperc h Unit s 1 - 5 • Norther n Anchov

y Unit s 1-

5 

# t l

Jan-7 9 Feb-7 9 Mar-7 9 Apr-7 9 May-7 9 Jun-7 9 Jul-7 9 Aug-7 9 Sep-7 9 Oct-7 9 Nov-7 9 Dec-7 9 Jan-8 0 Feb-8 0 Mar-8 0 Figur e 5-9a . Mea n monthl y combine d concentration s o f th e mos t abundantl y impinge d fishe s at th e Mos s Landin g Powe r

Plan t Unit s 1 throug h 5 intak e (PG&E , 1983) .

• Norther n Anchov

y Unit s 6 , 7 • Shine rSurfperc h Unit s 6 , 7 • Topsmel t Unit s 6 , 7 • Pacifi c Herrin g Unit s 6 , 7



# ,m , 

# H.H , 

# , , Jan-7 9 Feb-7 9 Mar-7 9 Apr-7 9 May-7 9 Jun-7 9 Jul-7 9 Aug-7 9 Sep-7 9 Oct-7 9 Nov-7 9 Dec-7 9 Jan-8 0 Feb-8 0 Mar-8 0 Figur e 5-9b . Mea n monthl y combine d concentration s o f th e mos t abundantl y impinge d fishes at th e Mos s Landin g Powe r

Plan t Unit s 6 an d 7 intak e (PG&E , 1983) .

E9-053. 9 5-2 6 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P. 8

5. 0 Impingemen t Effect s
0.2 0 0.1 8 0.1 6 .£0.1 4 I 0.1 2 £ 0.1 0 o E S > 0.0 8

• i 0.0 6 0.04
0.0 0 D Cance rantennariu s Unit s 1- 5 • Cance ranthony i Unit s 1- 5

- • Cance rproductu s Unit s 1- 5

— i 

### • — _ . 

# 1 l _ Jan-7 9 Feb-7 9 Mar-7 9 Apr-7 9 May-7 9 Jun-7 9 Jul-7 9 Aug-7 9 Sep-7 9 Oct-7 9 Nov-7 9 Dec-7 9 Jan-8 0 Feb-8 0 Mar-8 0 Figur e 5-10a . Mea

n monthl y concentration s ofth e mos t abundantl y impinge d Cancer spp . crab s a

t the Mos s Landing Powe

r Plan t Unit s 1 throug

h 5 intak e (PG&E , 1983) .

0.0 3

0.0 2 E 1 0.0 2

a. E 0.0 1 - 0.0 0 D Cance rantennariu s Units 6 , 7 • Cance ranthony i Unit

s 6 , 7 • Cance rproductu s Units 6 , 7 -

• JLr- 

# u k Jan-7 9 Feb-7 9 Mar-7 9 Apr-7 9 May-7 9 Jun-7 9 Jul-7 9 Aug-7 9 Sep-7 9 Oct-7 9 Nov-7 9 Dec-7 9 Jan-8 0 Feb-8 0 Mar-8 0 Figur e 5-10b . Mea

n monthl y concentration s ofth e mos t abundantl y impinged Cancer

spp . crab s a

t the Mos s Landin g Powe

r Plan t Unit s 6 an

d 7 intak e (PG&E , 1983) .

E9-053. 9 5-2 7 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P. 9

5. 0 Impingemen t Effects Tabl e 5- 1 list s th e estimate dconcentration s (#/l,00 0 m 3 ) base d o n survey s take n fro mJanuar y 197 9 t o Marc h 1980 . Impingemen t survey s wer e take n a

t th e coolin g wate r

intake s fo r

Unit s 1 throug h 5 an d Unit s 6 an d 7 . Th e dat afo r th e surveys wa s use d t o calculat e a n estimate d concentratio n an d estimate dnumbe r impinge d pe r

da y fo r selecte d specie s o f

fish an d macroinvertebrate s at

eac h intake . Tabl e 5-1 . Estimate dConcentration s based o n Survey s take

n fro mJanuar y 1 , 197 9 throug

h Marc h 31 , 1980 .
Mea n Volume/Da y - Survey Date s (1,00 0 m 3 ) Mea n Volume/Da y - Calenda r Yea r (1.00 0 m 3 )

Northern anchov y Shine r perc h Topsmel t Pacifi c herrin g Pacifi c staghorn sculpi n Bocacci o Rockfish : Taxon : blac k

rockfish , chilipepper , coppe r rockfish , cowcod , darkblotche d rockfish , dwar f

rockfish , kel p rockfish , shortbell y rockfish , vermilio n rockfish . Abundan t Fish ; Northe manchovy , shine r perch , topsmelt , an d Pacifi c herring . To p Macroinvertebrates , Crabs ; Cancer antennarius. Cancer

anthonyi. Cancer

gracilis, Cancer jordani, Cancer

magister, Cancer oregonensis, Cancer

productus. Cancer

spp . Unit s 1 throug h 5 1,33 0 1,26 7 Estimate d Concentratio n (#/1,00 0 m 3 ) 0.788 2 0.309 9 0.154 2 0.133 0 0.056 9 0.064 4 0.000 9 1.385 4
0.113 5 Estimate d

Impinged/Da y (# ) 1,049 41 2 20 5 17 7 7 6 8 6 1 1,84 3 15 1 Unit s 6 an d 7

2,32 2 2,33 5 Estimate d Concentratio n (#/l,000m 3 ) 0.723 0 0.237 8 0.147 0 0.108 8 0.052 3 0.046 6 0.000 8 1.216 6 0.101 9 Estimate d

Impinged/Da y (# ) 1,67 8 55 2 34 1 25 3 12 1 10 8 2 282 4 23 7 Selecte dspecie s of

fish includ e abundan t

fish suc h a s norther n anchovy , shine r perch , topsmelt , an dPacifi c herring . Th e stagho msculpi n an d bocacci o wer e o f interes t an d wer e als o include d in th e impingemen t

analysis . Selecte d rockfis h wer e analyze d a s agrou p includin g blac k rockfish , chilipepper , coppe r rockfish , cowcod , darkblotche d rockfish , dwar f rockfish , kel p rockfish , shortbell y rockfish , an d vermilio n rockfish . Selecte d specie s o f cance r crab s wer e analyze dincludin g Cancer antennarius, Cancer

anthonyi, Cancer

gracilis, Cancer

jordani, Cancer magister, Cancer

oregonensis, Cancer

productus, an d Cancer

spp . Th e estimate dconcentratio n wa s determine d b y first calculatin g th e actua l concentratio n fo r eac h survey . Th e estimate dconcentratio n wa s the n calculate d b y takin g th e mean o f th e concentratio n fo r al l o f th e surveys . Th e mea n coolin g wate r intak e volum e fo r

al l th e surve y dates was utilize d t o convert

th e estimate dconcentratio n t o a n estimate d numbe r

impinge d pe r

day . Th e
E9-053. 9 5-2 8 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.1 0

5. 0 Impingemen t Effects 

### estimate d numbe

r o f eac h specie s impinge dper da y wa s calculate db y takin g th e produc t o f th e estimate d concentratio n an dth e mea n volum e fo r all o f the surveys . Th e norther

n anchovy ha

dthe highes t

estimate dconcentratio n ofth e selecte dabundan t fish fo r Unit s 1 throug

h 5 an dUnit s 6 an

d7 (a t 0.788 2 an d0.723 0 /1,00 0 m 3 

### respectively) . Th e topsmelt ha dth e secondhighes t

estimate dconcentratio n a

t 0.3099/1,00 0 m 3 

### fo

r Unit s 1 through 5 an

d 0.237 8 /1,00 0 m 3 

### fo

r Unit s 6 an

d7 . Shine r perch ha dthe thir dhighes t estimate dconcentratio n a

t 0.154 2 an d0.147 0 /1,00 0 m 3 

### fo r Unit s 1 through 5 an

dUnit s 6 an

d7 respectively . Pacifi c herrin g ha dth e fourt h highes t estimate dconcentratio n a

t 0.133 0 an d0.108 8 /1,00 0 m3



### . Th e remaining specie s o

f fis h analyzedha

drelatively lo

w concentrations . Staghor

n sculpin ha

d a n estimate dconcentratio n a t 0.056 9 (#/l,00 0 m 3 

### ) fo r Unit s 1 throug

h 5 an d0.052 3 /1,00 0 m 3 

### fo r Unit s 6 an d7 . Bocacci o ha

da n estimate dconcentratio n a t 0.064 4 an d0.046 6 /1,00 0 m 3 

### respectively fo

r Unit s 1 throug

h 5 an dUnit s 6 an

d7 . The selecte drockfis h ha da n extremely lo w estimate d concentratio n o f 0.000 9 /1,00 0 m

3 

### an d 0.000 8 /1,00 0 m 3 

### ) fo r Unit s 1 throug

h 5 an dUni t 6 an d7 . The dat afo r th e cance r crab s wer e evaluate das agroup . Th e estimate dconcentratio n fo r th e cance r crab s was 0.1135/1,00 0 m 3 

### fo r Unit s 1 throug

h 5 an d0.1019/1,00 0 m 3 

### fo

r Unit s 6 an

d 7 . 

## 5. 4 Rat e o

f Impingemen t an d Intak e Velocitie s Intak e velocitie s coul daffec

t th e rate o f impingemen

t i f ther e ar e larg e amount s o

f debri s presen

t i n th e water . Thi s relationship betwee n heavy debri s loading o

n th e screen s an

dincrease d impingemen

t wa s examine da

t the Morr o Ba y Powe r Plan t (PG&E , 1982) . Information was provide dby Far mPum p Irrigatio n (FPI ) o

n the expecte dapproach velocitie s o f atravelin g scree

n designe dto replac e th e existin g screen s a t th e Pittsburg Powe

r Plant . Followin g discussion s wit

h FPI o n variou s design aspect s FPI provide destimate s o f through

scree n velocitie s fo

r th e replacemen

t scree n desig n a t Pittsburg Unit s 1 through 4 andUnit s 5 and 6 intake s fo

r bot h hig h and low tid

e condition s (Tabl e 5-2) . The estimate dreplacemen t scree n desig n velocitie s wer

e compare dto previously reporte dintak e approach andthrough-screen design velocitie s fo

r Pittsburg Unit s 1 throug

h 4 an dUnit s 5 an

d6 . Assumin g tha

t the PG& E reporte dapproach an

dthrough-screen velocitie s wer e calculate dfo

r hig h tide conditions , the replacemen

t ofth e existin g travelin g screen s wit h FPI-typ e screen s wouldreduc e bot h existin g approac h an dthrough-screen velocitie s a t Unit s 1 throug

h 4 an dUnit s 5 and6 .

E9-053. 9 5-2 9 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.1 1 

# 1 1 5. 0 Impingemen t Effect s



# 1 1 i 1 I 

# 1 1 1 I I Tabl e 5-2 . Existin g an dProjectedApproac

h an d Through-Scree

n Velocitie s fo

r the Pittsbur

g Powe r Plant s Unit s 1 through 4 an d Unit s 5 an

d 6 Intakes . Approac h Velocit y (fps) Existing FP

I Replacemen

t Through-screen Velocit y (fps ) 1 Existing FP

I Replacemen

tJ Pittsburg Power Plan

t1 Unit s 1 throug h 4 ^J ^

Units5and 6 | (0.2 4 mps ) 0.65-1.1 1 (0.198-0.3 4 mps

) 0.60-1.0 5 (0.183-0.32 mps

) 2. 0 (0.6 1 mps ) 1. 5 (0.4 6 mps ) 0.7 5 J

(0.2 3 mps ) 0.6 9 1 (0.2 1 mps ) I Th e impact s o f

powe r plan t intak e velocitie s on fishe s hav e bee n widel y reviewe d an d published . Th e U.S . Fis h an dWildlif e Servic e ha s provide d th e genera l backgroun d an d understandin g t o asses s impact s o f

intak e velocitie s on fisherie s resources . Thei r publication s conclud e wit h a recommendatio n tha t

maximu mintak e velocitie s shoul d no t excee d 0. 5 fps . Ther e ar e numbe r o f factor s whic h g o int o estimatin g genera l guidanc e for approac h velocities . However , condition s var y fro msit e t o site , wit

h ag e clas s of

fis h an d specie s o f

fish . Th e basi s fo r

th e 0. 5 fp s recommendatio n ha s bee n investigate d for anumbe r

o f specie s an d size s i n specifi c intak e situations . Th e effec t

o f scree n approac h velocity on percen t impingemen t

o f larva l andjuvenil e stripe dbas s i n laborator y swimmin g trial s fo r period s o f

1 0 an d 3 0 minut e duratio n i s show n in Tabl e 5-3 . Tabl e S-3 . Impingemen

t of StripedBas s a

t Variou s Approac

h Velocities . Percen tStr i Testtim e an

d siz e rang

e 19-3 8 m m lengt h 10- mi n 90-14 0 m m je d Bas s Impinge d versu s Approac h Velocit y

0. 8 (0.24 mps ) 0 0. 5 (0.1 5 mps ) 10-mi n | 0 30-min j 0 0. 9 (0.2 7 mps ) 0 0.7 5 (0.23 mps ) 0 0 Velocit

y (fps) 1. 0 (0.3 0 mps ) 20 1. 0 (0.3 0 mps ) 0 2 1.

1 (0.3 4 mps ) 4 0 1. 5 (0.4 6 mps ) 0 1 1 1.

2 (0.37 mps ) 6 0 2. 0 (0.6 1 mps ) 8 3 2 1.

3 (0.4 0 mps ) 7 9 2. 5 (0.7 6 mps ) 2 9 1.

4 (0.43 mps ) 9 7

Source: EA, 1982 Intak e velocit y calculations , base don a n incline d screen-typ e replacemen t fo r th e Pittsbur g Powe r Plant , indicat e that

durin g hig h tid e th e existin g approac h velocitie s woul d decrease . Unit s 1 throug h 4 approac h velocitie s woul d decreas e fro m0. 8 fp s (0.2 4 mps ) t o 0.6 5 fp s (0.2 0 mps ) an dapproac h velocitie s woul ddecreas e fro m0. 8 fp s (0.2 4 mps ) t o 0.6 0 fp s (0.1 8 mps ) a t 

# 1 E9-053. 9 5-3 0 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.1 2

5. 0 impingemen t Effect s th e Unit s 5 an d6 intake . Base do n th e informatio n provide d i n Tabl e 5-3 , thi s reductio n i n intak e velocit y woul dhav e n o measurabl e effec t o n th e impingemen t

o f fishe s simila r

t o stripe d bass . Th e reduce dvelocitie s migh t benefi t mor e fragil e fish species . 

### 5.4.11mpingement

Survival

and Intake Velocities Th e reductio n o f

intak e an dscree n approac h velocitie s wil l increas e th e potentia l o f smal l fish survivin g impingement . Replacemen t ofth e existin g Unit s 1 throug h 5 travelin g screen s with lowe r velocit y inclined-typ e screen s woul d increas e th e potentia l for surviva l o f

impinge d fishes , assumin g that : 1 . fin e mes h scree n wa s use dt o remov e smal l fishes , an d 2 . th e fishe s wer e returne dt o th e sourc e wate r withi n afew minutes . Th e potential t o reduc e fis h losse s b y reduction s i n travelin g scree n approac h velocitie s i s illustrate din Tabl e 5-4 . Tabl e 5-4 . Surviva

l {%) o f StripedBas s Impinged Fou r Minute s a t Variou s Wate

r Velocities . Surviva l (% ) o f Striped Bas s Impinge

d Four Minute

s atVariou

s Wate r Velocitie s Size Clas s (mm

) 5.1-6. 9 7.0-8. 9 9.0-10. 9 11.0-12. 9 13.0-14. 9 15.0-16. 0 Weighte d Mea n Velocit y (fps) 0. 5 (0.1 5 mps ) 69 % 83 % 9 1 % 96 % 89 % 100 % 83 % 1. 0 (0.3 0 mps ) 62 % 84 % 90 % 88 % 94 % 96 % 80 % 1. 5 (0.4 6 mps ) 19 % 7 1 % 90 % 88 % 87 % 100 % 68 % Source : Alde

n Researc h Laborator

y an dSton e an dWebste r Engineering Corporation (1980) , a s cite d i n Ecologica

l Analysts , Inc. , 1982 . Note : Impingemen

t surviva l was detennine d9 6 hour s afte r impingemen

t an d ha s no t bee n corrected fo

r control survival . No test s wer

e conducted using fish < 1 6 m m(0.6 3 in. ) a

t a n approac h velocit y o f 0. 5 fp s (0.1 5 mps) . Sinc e th e size s offis h tha t benefi t mos t fro mreduce dimpingemen t velocitie s ar e fish smalle r than th e one s impinge db y MLPP' s existin g 3/ 8 in . (0.95 3 cm ) mes h screens , th e effec t o f inclined-typ e scree n replacemen t o n impingement

surviva l woul d b e minimal , if any , an d difficul t t o quantify . Th e abov e tabl e show s a n exampl e o f

impingemen t

surviva l represente db y arelativel y hard y species , stripe dbass . Th e impingement surviva l o f

large r size s an d adul t E9-053. 9 5-3 1 MLP P 316(b ) Resource Assessmen t 4-28-200 03 .1 3

5. 0 Impingemen t Effects 

### form s o f mor e fragil e specie s offish , suc h a s Pacifi c herring , wouldpotentiall y increas e wit h reduce dintak

e scree n approach velocities . Impingemen

t surviva l studie s (PG&E , 1983 ) wer e designe dto provide aquantitativ e basi s fo r estimatin g the surviva

l o f fishes an dmacroinvertebrates . Impingemen t surviva l wa s determine d fo r the following thre e mode s o f travelin g screen rotatio n operation : continuous , 1-hou r intermittent , an

d3-hou r intermittent . Th e differen

t rotatio n mode s limite dth e amoun t o f tim e impinged organism s wer

e heldo n the screens . Organism s wer e collecte dandinitia

l observation s o f aliv e or dea dwer e recorded . Animal s wer

e place d into aflow-through holdin g syste m containin g ambien

t water . They wer

e observe dperiodically throughout th e 96-hou

r holdin g period . Contro l experiment s wer e conducte dt o determin e th e mortalit y associate dwit

h th e sluicewa y collection , handling , an

dthe holdin g system s method s used . Fishe s wer e mainly collecte d fro

motter trawl s conducte di

n Mos s Landin g Harbor . Thes e contro l fishe s wer e hel d fo r 2 t o 4 day s befor

e testin g to allow the

mt o recove

r fro mcollectio n an

dhandlin g stresses . Initia l an dlong-ter msurviva l o f norther n anchovy , Pacific herrin g an dsilverside s wer

e characteristically lo

w a t bot h intakes . Increasin g th e frequency o f scree n rotatio n a

t Unit s 6 and 7 improvedth

e surviva l o f surfperc h bu t di dno t hav e muc h effec t a t Unit s 1 through 5 . Althoug h the surviva

l o f flatfis h increase dwit

h increase dscree

n rotation , th e number s o

f fishe s availabl e testin g wer

e low . Long-ter

msurviva l o f gobie s an dsculpin wa s high afte

r th e 3-hou r rotation . Surviva

l o f crab s wa s hig

h fro mUnit s 6 and 7 , although th e numbe r teste dwas small ; Unit s 1 through 5 cra

b surviva l wa s only 4 7 percent

wit h 3-hou r rotation , which increase d t o 7 0 percen t an d7 4 percent

fo r the 1-hou r an dcontinuou s rotatio n mode , respectively . I t i s importan

t t o not e tha t thes e studie s wer

e done o f organism s collecte dfro

mth e sluiceway s o

f th e intake s an dwer e no t perfonne do

n organism s returne dt

o th e Unit s 6 and7 discharge . Impinge d materia l fro mUnit s 1 through 5 was no t route dou t through th e discharg e i

n Elkhor n Slough , thu s no impinge dorganism s survived . 

## 5. 5 Conclusion s Th e author s ofth e first

316(b ) Demonstratio n (PG&E , 1983 ) use drecent trend s in th e commercia

l fisher y landin g statistic s fo

r th e Monterey Ba

y regio n to asses s entrainmen t an d impingemen

t effects . Fo r

example , th e tren din commercia l landing s of

northe manchovy , th e mos t abundantly impinge dan

dentraine dfish wa s showing agenera l increas e durin g th e 1970s . Norther n anchovy als o wa s th e larges t (i n term s o f biomass ) fisher

y i n Californi adurin g th e time o f th e 316(b ) work . I

t wa s conclude dtha

t it wa s unlikely tha

t th e norther

n anchovy populatio n coul dhav e supporte dsuc

h a n increase dcommercia

l harves t tren di f entrainment

and impingemen

t ha dpreclude dth e maintenanc e o f the existin g population . Norther n anchovy ar

e a pelagi c schoolin g specie s foun dfro mBaj aCalifornia , nort

h t o Alaska . I t

wa s als o note dtha

t du e E9-053. 9 5-32 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.1 4



# 1 I

1 

# 1 1 5. 0 Impingemen t Effect s

t o th e broaddistributio n an dhig h reproductiv e potentia l o f norther n anchovy , the y appeare d t o b e capabl e o f

sustainin g th e incrementa l mortalit y associate d wit h alarg e commerciall y harveste dspecies . Gobie s are bottom-dwellin g o r burrow-inhabitin g fishes foun d in th e subtida l an d intertida l area s in th e vicinit y o f

th e MLPP . Severa l specie s o f gobie s hav e bee n collecte d i n larva l ari d adul t fish survey s o f

th e are a(Nybakken , Cailliet , an d Broenkow , 1977) . Thes e specie s include : ba y goby , arro w goby , blackey e goby , yellowfi n goby , an d longja w mudsucker . Ther e i s n o commercia l fishery fo r

gobies . Becaus e n o informatio n existe d o n trend s i n abundanc e an d distributio n th e author s use dlif e histor y informatio n t o asses s potentia l impacts . The y reported , fromth e literature , that

gobie s hav e amoderatel y hig h reproductiv e potential , ahig h natura l mortalit y rate , ar e widel y distributed , an d ar e not subjecte d t o sport

o r commercia l harvesting . I t wa s als o note dtha

t extensiv e habitat

exist s in th e vicinit y ofth e plan t an d tha t becaus e o f

thei r bottom-dwellin g habits , very fe w reproductiv e adult s wer e susceptibl e t o impingement . Therefore , i

t ca n b e predicte dthat

th e impingemen t

losse s for

specie s considere d wer e negligibl e fo r th e MLP P operatin g a

t highe r intak e volume s than propose d fo r th e modernization . N o trend s wer e foun din th e area' s commercia l an d spor t fisheries , includin g thos e nea r th e plant , t o indicat e a n advers e impac t

du e t o impingemen t

losse s at th e powe r

plant . Sinc e impingemen t effect s on area-wid e fisherie s wer e qualitativel y undetectable , i t wa s conclude d tha t

existin g MLP P intak e technolog y represente d BT A t o minimiz e impingemen t effect s an d potentia l impacts . I n summary , modification s t o th e ne w combined-cycl e intak e wil l reduc e impingement . Th e coolin g wate r

volum e pumpe dthroug h th e ne w combined-cycl e intak e structur e wil l b e reduce d fro m381,00 0 gp m(1,44 1 m 3 /min ) t o 250,00 0 gp m(94 6 m 3 /min) . A s aresul t ofth e lowe r

flows, approac h velocitie s wil l decreas e fro m0. 9 feet pe r second (fps ; 0.2 7 meter s pe r second[mps] ) t o 0. 5 fp s (0.1 5 mps) . Th e ne w travelin g screen s wil l b e incline d a t a n approximat e angl e o f

73 ° fro mhorizontal , thu s providin g mor e surfac e scree n are atha t wil l resul t

i n lowe r thoug h scree n velocities . Thes e ne w angle dscreen s wil l b e mor e effectiv e at removin g debri s tha n th e conventiona l vertica l travelin g screen s an d wil l reduc e th e amoun t o f debri s i n th e are aofth e intake . Th e existin g intak e tunne l wil l b e drasticall y reduce d fromapproximatel y 35 0 f t (106. 7 m ) lon g t o approximatel y 1 0 feet (3. 1 m ) behin d th e ba r

racks . Th e shortenin g o f th e tunne l may hel p t o reduc e impingemen t o f schoolin g fishe s that

can becom e trappe d i n th e tunne l an dsubsequentl y impinged .

E9-053. 9 5-3 3 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.1 5



## 6. 0 COOLIN G WATE R SYSTE M IMPAC T ASSESSMEN T Th e entrainmen t

an dimpingemen t

effect s ofth e coolin g wate r syste mfor

th e propose d MLP P combined-cycl e (CC ) projec t hav e bee n assesse d o n th e basi s o f both historica l an d o n twelv e month s o f

recentl y complete dsurvey information . Th e assessmen t consider s both th e effect s o f entrainin g larva l fishe s an dmegalopa l cance r crab s an d impingin g large r fishe s an d invertebrate s i n th e coolin g wate r

intak e structur e (CWIS) . Th e thre e method s for

assessin g coolin g wate r

syste m(CWS ) effect s describe d i n th e MLP P Modernizatio n Projec t

Stud y Pla n wer e th e fecundity hindcastin g {FH) an d adul t equivalen t

los s {AEL) approache s an dempirica l transpor t modelin g {ETM). Thi s repor t contain s estimate s o f AEL an dFH wher e dat awer e availabl e t o parameteriz e thes e demographi c approaches . I t als o provide s estimate s o f

proportiona l entrainmen t {PE) fo r inclusio n i

n th e ETM. Th e estimate s o f tota l entrainmen t

mortalit y ( P

M ) generate d fro

mth e ETM

represen t 9 month s ofth e data ; i t

i s unlikel y that

th e remainin g thre e month s ofdat awil l significantl y chang e result s presente d here . Result s fro mth e MLP P entrainmen t studie s an d previou s impingemen t studie s (PG&E , 1983 ) ar e use dt o predic t

th e potentia l entrainmen t an d impingemen t

effect s ofth e propose d combined

cycl e CWS . Estimate s o f larva l fish an d megalopa l cance r crab concentration s (#/m 3 ) sample d at th e MLP P CWI S an dmultiplie db y th e projecte d combined-cycl e dail y intak e volum e (m 3 ) provid e estimate s ofth e tota l numbe r o f larva l fishe s an d megalopa l cance r crab s tha t

migh t b e withdraw n b y th e powe r

plant' s CWS . Similarly , larva l fish an d megalopa l cance r cra b concentration s estimate dfro mMLPP' s sourc e wate r bodie s (Elkho mSlough , Mos s Landin g Harbor , an dMontere y Bay ) an dmultiplie d b y thei r dail y tida l volume s produc e estimate s o f loca l larva l an dmegalopa l abundance . B y comparin g th e numbe r o f larva e an d megalop s withdraw n b y th e powe r

plan t t o th e numbe r

availabl e (i.e. , at

risk t o entrainment) , a n estimat e o f fractiona l los s {PE) ca n b e generate d for eac h taxo n o r

species . Th e magnitud e ofthes e fractiona l losse s ca n serv e a s aguid e t o determinin g unacceptabl e CW S effect s tha t coul d caus e populatio n impact s i n th e for mo f long-ter mdeclines . Th e contex t require d t o interpre t

thes e fractiona l losse s come s fro mfishery managemen t practice s an d othe r

form s o f stoc k assessments . I n th e cas e o f aharveste d species , thes e fractiona l losse s mus t b e considere d a s additiv e t o harves t

losse s whe n assessin g impact s an d an y potentia l for populatio n decline . I n th e followin g descriptio n an ddiscussio n o f ou r preliminar y findings , severa l consisten t trend s ar e apparent . Thes e includ e lo w diversit y o f entraine d specie s an d relativel y lo w magnitud e proportiona l losses . I n additio n t o th e lo w diversit y o f entraine d specie s an d smal l proportiona l losses , th e surve y result s sho w very littl e entrainmen t o f importan t

commercia l o r

recreationa l species .

E9-053. 9 6- 1 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.1 6

6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### Historica l information an

dpresen t finding s o

n MLP P CWS effects an

dprojecte deffects ofth e ne w combined-cycl e facilit

y ar e reviewe dan

dassesse dfo

r eigh t ofth e mos t

abundan t larva l fish tax aan dal l megalopa

l cance r crabs . Th e eigh t fish tax acomprise dove

r 9 5 percent

by abundanc e ofth e larva

e entrained . Followin g thi s assessmen t o f MLP P CWS effects , avariet

y o f alternativ e intak

e technologie s t

o reduc e thes e entrainmen

t an dimpingemen

t effects ar e reviewe di n Sectio n 7—Evaluation o f Alternativ e Intak

e Technologies . Bot

h th e feasibilit

y an d cos t ofth e variou s technologie s ar e weighedagains t

their effectivenes s t

o reduc e an

y identified CW S effects o r potentia l impacts . Th

e economi c cos t

of reducin g CWS impact s through implementin g alternativ e technologie s mus t no t b e wholl y disproportionat

e t o th e benefi

t gained i n term s o f minimizin g an

y advers e environmenta

l impacts . 

## 6. 1 Entrainmen t Effect s Assessmen t Fo r thi s report , w e hav e focuse dou r assessmen

t o f entrainmen

t effects o n th e eigh t mos t abundan t larva l fish tax aan

dall cance

r cra b megalops . Thes e selecte dspecie s ar e carrie d forwar di n ou r analysi s a s target

specie s becaus e o

f thei r hig h relativ e abundanc e o

r commercial/recreationa

l importance . Th

e larva l fis h specie s o

r tax agroup s chose

n fo r thi s preliminar y assessmen

t ar e th e mos t abundan t foun di n ou r entrainmen

t samplin g t

o date . The

y ar e the unidentifie dgobies , ba y goby , blackey e goby , Pacifi c staghor n sculpin , whit

e croaker , blennies , longja

w mudsucker , an

dPacifi c herring . Two specie s tha t occurre di

n relativ e low abundance , Pacifi c herrin g an dwhit e croaker , wer

e include di

n th e assessmen

t becaus e the

y represente dth e only fish specie s o f commercia

l or recreationa

l valu e fo r huma n consumptio n collecte di n ou r entrainmen

t samples . However , a s discusse di n th e following assessmen

t ofth e tw o species , thei r

lo w abundanc e make s i

t nearly impossibl e t

o quantitativel y asses s an

y MLP P entrainmen

t effects o r potentia l population-leve l impacts . The Cancer spp . megalop s assesse d ar e hair y rock crab , yello w rock

crab , brown roc

k crab , dungenes s crab , re drock crab , an d slende r roc k crab . Th e yello w rock

crab , brown rock

crab , dungenes s crab , an

dredrock cra b all hav e som e commercia

l importance . The assessmen

t evaluate s first

th e effects of

MLP P CW S entrainment

on larva l form s o f fishes an dcance r cra b megalop s followedb y anarrativ e assessmen t of impingemen

t effects an d th e potentia l reductio n ofthes e effects by th e modernizatio n ofth e combined-cycl e intak e structur e an dflows . Sourc e Wate r Volum e 

### Th e calculatio n of

ETM, illustrate din Equation s 9 to 14 , require s estimate s ofth e numbe r o f larva e and megalop s entrained , the numbe r of larva e an dmegalop s i

n th e sourc e water populatio n a

t risk to entrainment , an

da n estimat e o f larva l ag e a t entrainment . The numbe

r of E9-053. 9 6- ? MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.1 7
6. 0 Coolin g Wate r Syste m Impac t Assessmen t larva e an dmegalop s entraine di s estimate d fro mrepresentativ e sample s o f entraine d organis m concentration s multiplie db y th e tota l volum e ofth e powe r plant' s intak e water . Th e numbe r o f sourc e wate r

larva e an dmegalop s a

t risk i s estimate d b y multiplyin g representativ e sample s o f thei r sourc e wate r

populatio n concentration s b y sourc e wate r volumes . Larva l age s ar e estimate dfro mliterature-base dgrowth rate s an d reporte d length s a t th e earl y lif

e stage s o f hatching , yolk-sa c stag e completion , flexion , an d transformatio n (Wang , 1986 ; Moser , 1996) . Megalopa l duration , megalopa l survival , an d ag e a t maturatio n wer e estimate d fro mth e literatur e for

cance r crabs . Th e MLP P sourc e wate r

are awas divide d int o thre e sub-area s for th e purpose s o f

stud y an d analysis . Informatio n on MLP P area' s marin e geography , hydrography , an d ecolog y wa s employe din analysi s an ddiscussio n with th e TW G t o defin e a priori thre e sub-element s o f sourc e wate r

populatio n a

t ris k t o entrainment . Th e define d element s o f sourc e wate r

populatio n ar e Montere y Bay , Mos s Landin g Harbor , an d Elkho mSlough . Th e shallo w tida l channel s an d tributaries ofth e Elkhorn Slough , whic h floo d an d drai n extensiv e Salicornia marsh , eelgras s beds , an dmudflats , provid e habita t for assemblage s o f

invertebrate s an d fishe s characteristicall y differen t fromthos e foun di

n th e Mos s Landin g Harbor' s habitat s o f dee p channel s surrounde d b y wharve s an dpilings . Th e enormou s depth s ofth e Montere y Canyo n li e jus t beyon d th e harbor' s entranc e int o th e Montere y Bay . Les s than amil e offshor e canyo n depth s can excee d on e mile . Nort h an dsouth ofth e harbo r entrance , th e steep , ofte n rock y wall s o f thi s canyo n rise , becomin g th e broad , shallo w depth s o f san d beac h an d mu d tha t characteriz e th e majority ofth e bay' s nearshor e are afromSant aCru z t o Monterey . Th e tw o distinctl y differen t botto msubstrat a i n combinatio n with open-ocea n beac h an d submarin e canyo n oceanographi c condition s provid e habita t for athir dassemblag e o f

invertebrate s an d fishes . Th e method s use dt o calculat e th e volume s ofeac h ofth e thre e sourc e wate r element s an d thei r estimate dsourc e wate r

volume s ar e give n i n Sectio n 3.4.2.1 . Th e geographica l locatio n an d exten t ofth e thre e sourc e wate r sub-area s ar e illustrate d i n Figur e 3-2 . Sourc e Wate r

Sub-are aVolum e (m 3 ) Montere y Ba y 275,000,00 0 Elkho mSloug h 21,100,00 0 Mos s Landin g Harbo r

2,200,00 0 Combined-Cycl e Unit s 1,360,00 0 (maximu mvolume ) Empirica l Transpor t

Mode l {ETM) output s ar e presente d alon g with PE estimate s for

th e Jun e 199 9 throug h Februar y 200 0 sourc e wate r surveys . Proportiona l entrainmen t {PE) values wer e calculate dprio r

t o ETM values . Th e tw o value s differ b y th e metho d use d t o estimat e th e exten t E9-053. 9 6- 3 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.1 8

6. 0 Coolin g Wate r Syste m Impac t Assessmen t

o f sourc e wate r

populatio n a

t ris k i n tim e an d space . Fo r

example , PE

value s calculate dfo

r th e Montere y Ba y sourc e wate r elemen t approximate d it s volum e a s tha t containe d i n a

n are a2 km south an dnorth ofth e harbo r entrance , extendin g fro mth e shorelin e ou t t o adept h o f

5 0 m . Give n th e presenc e o f

stron g longshor e current s an d upwellin g in thi s area , i t wa s assume d tha t sourc e wate r

population s o f

larva l an d megalopa l specie s i n thi s elemen t exten d b y curren t transpor t wel l beyon dou r

first orde r approximatio n o f

sourc e wate r

exten t an d volume . Howeve r at thi s time , w e hav e no t

employe d curren t

spee d an d larva l duratio n t o enlarg e ou r initia l estimat e o f

Montere y sourc e wate r

volume . Ou r

ETM calculation s ar e basedo n ou r initia l approximatio n o f

ba y volume . A s describe d in Sectio n 3 , th e TW G requeste d tha t w e calculat e a secon dse t

o f ETM value s substitutin g th e harbo r an d sloug h sourc e wate r volum e for

th e Montere y Bay sourc e wate r volume . ETM

value s base d o n thi s orde r o f magnitud e volum e differenc e ar e presente dtogethe r wit h values compute d usin g Montere y Bay' s sourc e wate r volume..I n computin g ETM values , PE's ar e als o weighte d b y th e monthl y survey fractio n (f~) o f sourc e wate r

populatio n a

t risk . Thi s facto r

ca n significantl y affec t

th e outcom e o f

combinin g a serie s o f PE values . A n ETM

valu e coul d no t

b e compute d fo

r dungenes s crab du e t o alac k o f co-occurrenc e o f

megalop s i n entrainmen t an d sourc e wate r

samples . Th e majorit y of ETM value s for th e othe r crab specie s wer e base d on asingl e PE value . 

### Demographi c Approache s fo r Estimatin g Entrainmen t Effect s Entrainmen t

losse s wer e estimate dfro mtota l larva l an d megalopa l entrainmen t at MLP P usin g fecundity hindcas t

{FH) an dadul t

equivalen t

los s {AEL) models . Thes e model s requir e species

specifi c estimate s ofage , growth , fecundity , an d survivorship . Thes e dat awer e availabl e fo r fou r ofth e eigh t

targe t fish taxa : ba y goby , blackey e goby , combtooth blenny , an d Pacifi c herring . Fo r

ba y goby , n o species-specifi c estimate s o f surviva l wer e availabl e i n th e literature . Therefore , w e wer e unabl e t o estimat e FH for thi s species , bu t

wer e abl e t o estimat e AEL b y substitutin g juvenil e an dadul t survivorshi p dat ao n thre e sympatri c gobiid s fro mBrother s (1975) . Fo r

th e othe r taxa , eithe r

species-specifi c fecundity o r mortalit y rate s wer e availabl e t o parameteriz e on e o r

bot h ofth e demographi c approache s for estimatin g entrainmen t

effects . Thes e tax ainclude dwhit e croaker , Pacifi c herring , hair y roc k crab , yello w roc k

crab , brow n roc k crab , dungenes s crab , red roc k crab , an d slende r

roc k crab . AEL

an d FH los s estimate s coul d not b e compute dfor

Pacifi c staghor n sculpi n du e t o alac k o f demographi c information . Th e derivation s ofthes e approache s ar e detaile d i n Sectio n 3 an d th e availabl e lif e histor y dat a ar e summarize dfor

eac h taxo n i n Sectio n 4 o f thi s document . 

## 6. 2 Unidentifie d Gobie s Th e unidentifie dgob y categor y comprise d th e larges t numbe r an d highes t

densit y o f

al l entraine dtaxa . Evidenc e fro mou r recen t analysi s o f

thi s taxon , discusse d i n Sectio n 4 , suggest s E9-053. 9 6- 4 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.1 9
6. 0 Coolin g Wate r Syste m Impac t Assessmen t tha t ther e ma y b e at

leas t tw o specie s o f

gobie s i n thi s unidentifie d category . Becaus e o f thei r commo n abundanc e i n habita t foun d i n th e Mos s Landin g area , arro w gob y probabl y mak e u p th e majorit y ofth e larva e i n thi s category . Previou s investigator s hav e presume d s o in earlier studie s ofth e Elkho mSloug h an dMos s Landin g Harbo r (Nybakke n e t

al. , 1977) . A close r taxonomi c examinatio n o f ou r sample s ha s reveale d tha t man y unidentifie d gobiida e larva e ar e ver y simila r

meristicall y an dmorphometricall y t o th e descriptio n o f arro w gob y larva e i n Wan g (1986 ) an dMose r

(1996) . However , tw o prominen t peak s i n unidentifie d gob y concentratio n (Figur e 4-8) , on e i n uppe r Elkho mSloug h an d anothe r in th e ocea n a

t th e fa r extrem e o f

ou r stud y area , suggest s th e possibilit y o f tw o differen t

specie s i n th e unidentifie d gob y category . Thi s findin g bring s ou t

avery importan t

poin t i n th e applicatio n o f

impac t assessmen t

methods . Althoug h w e ca n analyz e th e proportiona l los s of agroupe d taxo n suc h a s unidentifie d gobies , a s w e hav e don e i n thi s section , it i s no t possibl e t o assig n th e significanc e ofthes e losse s t o a particula r species ' population . However , i f w e findthat

th e entrainmen t

losse s ofa n unidentifie d taxo n ar e proportionall y lo w compare d t o ou r estimate s o f

sourc e supplies , i

t provide s ameasur e o f assuranc e tha t

th e populatio n ofth e unknow n specie s w e hav e collecte d wil l no t b e adversel y affecte d b y entrainment . Eve n thoug h th e sample s ma y contai n mor e tha n asingl e species , i f th e proportio n o f

specie s i n th e unidentifie d categor y remain s th e sam e amon g entrainmen t an d sourc e wate r

samples , ou r

estimat e o f

CW S effect s an d impact s i s unaffected . W e simpl y wil l not kno w t o wha t

specie s the y apply . 

### Empirica l Transpor

t Mode l (ETM) Th e proportiona l entrainmen t value s for

unidentifie d gobie s ar e fa r belo w an y valu e tha t

coul d represen t consequentia l intak e effect s o r potential for

long-ter mpopulatio n declines . Th e rang e o f PE value s an dstandar derror s ar e summarize d i n Tabl e 6-l aan d b for th e nin e survey s fro m Jun e 199 9 throug h Februar y 2000 . Th e ETM value , base d o n th e combine d Montere y Ba y sourc e wate r

volum e i s 0.0 3 an dth e ETM valu e substitutin g harbor/sloug h sourc e wate r volum e for ba y volum e i s 0.11 .

E9-053. 9 6-5 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.2 0

6. 0 Coolin g Wate r Syste m Impac t Assessmen t Tabl e 6-la . Fina

l ETM Outpu t Unidentifie d Gobie s Gobiida e spp . ETM

calculation s based o

n Montere y Ba y volum e = 275,000,00 0 m 3 , Elkho mSlough volum

e = 21,100,00 0 m 3 , Mos s Landing Harbo

r volum e = 2,200,00 0 m

3

. ETM Estimat e (PM) 0.0263 8 Std . Err . 0.0042 3 Survey Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Jan 200 0 24 Fe b 200 0 PE Perio d Start 1 8 May 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Ja n 200 0 PE

Estimate . 0.0062 4 0.0013 1 0.0044 4 0.0113 3 0.0004 8 0.0048 1 0.0047 8 0.0032 5 0.0050 4 PE

Std . Err . 0.0013 1 0.0005 8 0.0011 6 0.0048 5 0.0003 6 0.0005 1 0.0011 3 0.0004 6 0.0002 4 +2S E

0.0263 8 -2S E 0.0263 8

F ; 0.1447 5 0.0909 9 0.0268 6 0.0435 9 0.0504 7 0.1944 1 0.15840 0.0691 1 0.2214 3 F ,

Std . Err . 0.0027 8 0.0006 5 0.0001 2 . 0.00020 0.0004 6 0.0009 4 0.0009 7 0.0013 8 0.0016 1 Larva l

Duratio n 5.6 9 5.6 9 5.6 9 5.6 9 5.6 9 5.6 9 5.6 9 5.6 9 5.6 9 Note : Dat aar e preliminary . Tabl e 6-lb . Fina

l ETM Outpu t fo r Unidentifie d Gobie s Gobiidae spp . ETM calculation s base

d o n Montere y Ba y volum e = 21,100,00 0 m \ Elkho mSlough volum e = 21,100,00 0 m 3 , Mos s Landing Harbo r volum e = 2,200,00 0 m

3

. ETM Estimat e (PM) 0.1069 0 Std . Err . 0.0066 8 Surve y Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Ja n 200 0 2 4 Fe b 200 0 PE Perio d Start 1 8 Ma y 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Ja n 200 0 PE

Estimat e 0.0097 8 0.0044 8 0.0245 5 0.0132 9 0.0013 2 0.0296 1 0.0179 9 0.0171 9 0.0315 6 PE

Std . Err . 0.0022 1 0.0010 9 0.0048 6 0.0059 6 0.0009 3 0.0030 7 0.0043 1 0.0022 1 0.0019 5 +2S E

0.10690 2S E 0.10690
F ( 0.1447 5 0.0909 9 0.0268 6 0.0435 9 0.0504 7 0.1944 1 0.15840 0.0691 1 0.2214 3 Std . Err .

0.0027 8 0.0006 5 0.0001 2 0.0002 0 0.0004 6 0.0009 4 0.0009 7 0.0013 8 0.0016 1 Larva l

Duratio n 5.6 9 5.6 9 5.6 9 5.6 9 5.6 9 5.6 9 5.6 9 5.6 9 5.6 9 Note : Dat aar e preliminary .

E9-053. 9 6- 6 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.2 1 

# r 6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### Fecundit y Hindcas t Mode l (FH) Th e tota l annua l larva l entrainmen

t fo r unidentifie dgobie s wa s use dt o estimat e th e numbe

r o f breedin g female s neede dt

o produc e th e numbe

r o f larva e entraine dshown i

n Tabl e 6-2 . Th e estimate dnumbe

r o f breedin g female s (FH) whos e fecundit y equal s th e estimate dtota l los s of entraine d larvae i s calculate dassumin g a n ag e a t maturatio n of

1. 0 yea r an da n averag e lifespa

n o f 2. 5 years . The numbe

r o f adul t female s hindcas t

fro mthe larva

e entraine da

t MLP P combined-cycl e intak

e wa s 300,00 6 (9 0 percent

C.L . = 97,11 3 t

o 926,792) . Table 6-2 . Annua

l Entrainmen

t Estimate s fo

r Unidentifie

dGobies Gobiida

e spp. : Marc

h 1 , 199 9 throug h Februar y 29 , 2000 . Annua l Entrainmen t 268,968,00 0 Annua l Std . Erro r 3,206,74 0 C V 1 %

FH Estimate s Unidentifie d Gobie s Gobiidae spp . FH Estimat e 300,00 6 FH

Std . Erro r 205,70 5 Uppe r FH 90 % C.L . 926,79 2 Eg g Surviva l 1. 0 Yol k

Sa c Surviva l 1. 0 Lowe r FH 90 % C.L . 97,11 3 Larva l Surviva l 0.68307 8 1 Egg s

pe r Yea r 1,75 0 Averag e

lifespa n (yrs ) 2. 5 Ag e a

t Maturatio n 1. 0



### The uncertaint

y o f ou r FH estimat e wa s attribute db y sensitivit y analysi s t

o th e uncertaint

y ofth e model parameter s o f

averag e lifespan , fecundity , and larva l survivorship , in tha

t order . Adul t Equivalen t Los s (AEL) N o independen

t estimat e o f surviva l o f unidentifie dgobie s between ag e o f entrainmen

t an d adult stag e wa s availabl e i

n th e literature . Th e specie s o f

gobie s tha

t ma y compris e thi s taxo n hav e neithe r commercia

l no r recreationa

l fisher y value , an

dther e i s littl e informatio n o n thei r ecologica l rol e i n th e community . Ther

e ar e no catch dat

atha t ca n b e usedt

o compar e harves t mortalit y rate s to entrainment

mortalit y rate s becaus e ofth e absenc e o f

fisher y datafo r thi s species . N o estimate s of stock siz e o r densit y ar e availabl e to conver

t entrainment

mortalit y rate s into a

n estimat e o f adult equivalent

loss , assumin g n o compensator

y mortality . Result s of ETM analyse s usin g th e tw o differen t sourc e wate

r volume s sho w tha

t th e powe r plan t ma y annually entrai n approximately 3 percent (Tabl e 6-la ) o

r 1 1 percent

(Tabl e 6-lb ) ofth e

E9-053. 9 6- 7 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.2 2

6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### unidentifie dGobiida

e taxon larva

e fro mthe MLP

P sourc e water . A

n independen

t estimat e of FH yield s apredicte dtheoretica l los s of 97,11 3 t o 926,79 2 adult s (female s only) . 

## 6. 3 Ba y Goby Th e proportiona

l entrainmen

t value s fo r th e ba y gob y hav e remaine dquite lo w throughou t th e nine month s of

sourc e wate

r an dentrainmen

t studie s a s show

n i n Tabl e 6-3 . The rang e of

value s fro maPE of zer o t o 0.0 3 (Tabl e 6-3a

) an dzero t o 0.1 7 (Tabl e 6-3b ) hav e remaine da t thes e lo w level s i n spite o f larg e fluctuation s i

n th e estimate dnumbe

r of entraine dgobies . I

n 8 ofth e 9 entrainmen

t survey s tha

t coincide dwit

h sourc e wate

r surveys , the number s o f

ba y goby increase d i n the lat e evenin g entrainmen

t cycle s afte

r the daytim

e sourc e water

samplin g (Figur

e 4-10) . Empirica l Transpor t Mode l (ETM) 

### The ETM value s fo r ba y goby foun

di n Tabl e 6- 3 ar

e fa r belo w value s tha

t woul drepresent consequentia

l intak e effect s o r an y potentia l fo r long-ter mpopulatio n declines . The ETM valu e based o n Monterey Ba

y sourc e wate

r volum e i s 0.0 4 an d0.2 1 whe

n harbor/sloug h sourc e wate r volum e i s substitute dfo

r Monterey Ba

y sourc e wate

r volume . The MLP

P entrainment

impac t evaluatio n give s no indicatio n o f an y potentia l impact s ofth e ne

w combined-cycl e project' s CWS o n th e area' s population s o f ba y goby .

E9-053. 9 6-8 MLP P 316(b ) Resource Assessmen t

. 4-28-200 0P.2 3 

# I 1 I 6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

# i l i i 

# t l i i 

# i i I 

# i i i i Tabl e 6-3a . Fina l ETM Outpu t Ba y Gob y Lepidogobius lepidus. ETM calculation s base d o

n Montere y Ba y volume = 275,000,00 0 m 3 , ElkhomSloug

h volum e = 21,100,00 0 m \Mos s Landing Harbo

r volum e = 2,200,00 0 m \ ETM Estimat e (PM) 0.0386 2 Std . Err 0 0.0087 8 Survey Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Jan 200 0 2 4 Fe b 200 0 PE Perio d Start 1 8 Ma y 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Jan 200 0 PE

Estimat e 0.0000 0 0.0018 1 0.0021 4 0.0291 2 0.0012 6 0.0059 5 0.0094 5 0.0179 2 0.0267 1 PE

Std . Err . 0.0000 0 0.0004 8 0.0029 8 0.0180 5 0.0005 4 0.0011 4 0.00640 0.0072 0 0.00873 ' +2S E

0.0386 2 2S E 0.0386 2

F , 0.0227 9 0.0278 7 0.0315 6 0.0569 4 0.0596 4 0.2850 3 0.2521 7 0.1102 6 0.1537 4 Std . Err .

0.0008 7 0.0005 3 0.0001 5 0.0003 2 0.0004 0 0.0012 6 0.0015 2 0.0025 0 0.0024 5 Larva l

Duratio n 3.2 9 3.2 9 3.2 9 3.2 9 3.2 9 3.2 9 3.2 9 3.2 9 3.2 9 Tabl e 6-3b . Fina

l ETM Outpu t fo r Ba y Gob y Lepidogobius lepidus. ETM calculation s based o

n Montere y Ba y volume = 21,100,00 0 m 3, ElkhomSloug

h volum e = 21,100,00 0 m 3 , Mos s Landing Harbor volum e = 2,200,00 0 m

3

. ETM Estimat e (PM) 0.2144 2 Std . Err . 0.0405 8 Surve y Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Jan 200 0 2 4 Fe b 200 0 PE Perio d Start 1 8 Ma y 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Ja n 200 0 PE

Estimat e 0.00000 0.0165 4 0.0205 5 0.0490 1 0.0058 9 0.0397 2 0.0682 1 0.1336 7 0.1743 4 PE

Std . Err . 0.00000 0.0044 1 0.0257 5 0.0326 8 0.0020 7 0.0068 3 0.0484 5 0.0386 9 0.0530 8 +2S E

0.2144 2 -2S E 0.2144 2

F , 0.0227 9 0.0278 7 0.0315 6 0.0569 4 0.0596 4 0.2850 3 0.2521 7 0.1102 6 0.1537 4 F ,

Std . Err . 0.0008 7 0.0005 3 0.0001 5 0.0003 2 0.0004 0 0.0012 6 0.0015 2 0.0025 0 0.0024 5 Larva l

Duratio n 3.2 9 3.2 9 3.2 9 3.2 9 3.2 9 3.2 9 3.2 9 3.2 9 3.2 9 Note : Dat aar e preliminary .

E9-053. 9 6- 9 MLP P 316(b ) Resource Assessmen t 4-28-200 0

### IP " 

# 1 

# i i i i i 

# i i i § 

# i i 

# I i i i i i i 6. 0 Coolin g Wate r Syste m Impac t Assessmen t



### Fecundit y Hindcas t Mode l (FH) N o independen t

estimat e o f

surviva l o f

ba y gob y betwee n ag e o f entrainmen t

an d th e eg g stag e wa s availabl e i n th e literature . 

### Adul t Equivalen t Los s (AEL) Th e tota l annua l MLP P combine dcycl e entrainmen t o f ba y gob y (Marc h 199 9 t o Marc h 2000 ) wa s use dt o estimat e th e numbe r o f equivalen t

adult s theoreticall y los t

t o th e populatio n show n in Tabl e 6-4 . Th e estimate dnumbe r o f equivalen t

adult s correspondin g t o th e numbe r o f larva e that woul dhav e bee n entraine db y th e propose d MLP P combined-cycl e intak e wa s 1,045,58 8 (9 0 percen t

C.L . = 520,29 0 t o 2,101,241) . Tabl e 6-4 . Annua

l Entrainmen

t an dAEL Estimate s fo

r Ba y Gob y Lepidigobius lepidus: Marc h 1 , 1999 throug

h Februar y 29 , 2000 . Annua l Entrainmen t 152,755,00 0 Annua l Std . Erro r 643,86 0 C V 0 % AEL Estimate s fo

r Ba y Goby Lepidogobius lepidus AEL Estimat e 1,045,58 8 AEL Std . Erro r 443,62 7

Surviva l Early Larva e 0.01277 5 Surviva l

Lat e Larva e 1. 0

- . "•'-"••."-.. ; ;"','..'";

- - t . • , '.- • ' .-.- - .•<':'.—.?•• -'"•' ' Uppe r 90 % C.L . 2,101,24 1 Surviva l

Early Juv . 1. 0 Surviva l

Juv . I 1. 0 Surviva l

Juv . II 1. 0 Lowe r 90 % C.L . 520,29 0 Surviva l Juv . Il l I. O Surviva l

Juv . IV 1. 0 Surviva l

Pre-Recrui t 0.53579 7

Th e uncertaint y o f

our^£ X estimat e i s mos t affecte d b y th e mode l parameter s o f earl y larva l an d earl y juvenil e survivorship . Uncertaint y i n ou r entrainmen t

estimate s ha d relativel y littl e effec t o n th e confidenc e i n th e estimate dAEL. Th e ba y gob y ha s neithe r commercia l no r

recreationa l fisher

y valu e an d ther e i s littl e informatio n o n thei r

ecologica l rol e i n th e community . Ther e ar e n o catc h dat atha t ca n b e use d t o compar e harves t

mortalit y rate s t o entrainmen t mortalit y rate s becaus e ofth e absenc e o f fishery dat afor

thi s species . N o estimate s o f stoc k siz e o r densit y ar e availabl e t o conver t FH o r

E9-053. 9 6-1 0 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.2 5

6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### AEL entrainmen

t effects int

o estimate s of

fractiona l loss , eve n assumin g no compensator y mortality . Result s o f ETM analyse s using th e tw o differen t sourc e wate

r volume s sho w tha

t th e powe r plan t ma y annuall y entrain approximately 4 percent (Tabl e 6-3a

) or 2 1 percent

(Tabl e 6-3b ) ofth e ba

y goby larva e fro mth e MLP

P sourc e water . A

n independen

t estimat e of AEL yield s apredicte d theoretica l los s of 520,29 0 t o 2,101,24 1 adult s (male s an dfemale s combined) . The ETM estimat e i s not larg e enoug

h t o b e of an y importan

t consequenc e t

o th e loca l populatio n o f

adul t ba y goby . Th

e larg e estimat

e o f AEL losse s reflect s anumbe

r o f uncertaintie s i

n mode l inpu t fo r lif e histor y parameter s o f

thi s specie s an

dlarg e sourc e wate

r concentration s i

n th e vicinit

y ofth e powe r plan t intake . 

## 6. 4 Blackey e Gob y Th e proportiona

l entrainmen

t value s fo r th e blackey e goby hav e varie da n orde r o f magnitud e throughou t the nin e month s o

f sourc e wate

r an dentrainmen

t studie s a s shown i

n Tabl e 6-5 . Change s i n PE value s rangin g fro

mzer o t o 0.0 4 (Tabl e 6-5a

) an dfro mzero t o 0.0 5 (Tabl e 6-5b ) correspond t

o fluctuation s i

n the estimate do

f numbe r o f entraine dblackey e goby . O n severa l occasion s the number s ofth e blackey e gobie s increase di n th e lat e evenin g entrainmen

t cycle s following th e daytim

e sourc e wate

r sampling . Empirica l Transpor t Mode l (ETM) Th e ETM value s fo r blackey e gob y a s show

n i n Figur e 6- 5 ar e fa r belo w value s tha

t would represen t consequentia

l intak e effects o r

an y potentia l fo r long-ter mpopulatio n declines . Th e ETM value , basedo

n the Monterey Ba

y sourc e wate

r volum e i s 0.0 4 an d0.0 7 base da substitutio n o f

harbor/sloug h volum

e fo r Monterey Ba

y volume . The MLP

P entrainmen

t impact evaluatio n give s n o indicatio n of an y potentia l impact s ofth e ne

w combined-cycl e project' s CW S o n th e area' s blackey e goby .

E9-053. 9 6-1 1 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.2 6

6. 0 Coolin g Wate r Syste m Impac t Assessmen t Table 6-5a . Fina

l ETM Outpu t fo r Blackeye Gob

y Coryphopterus nicholsi. ETM calculation s based o n Montere

y Ba y volume = 275,000,00 0 m 3, Elkho mSloug

h volum e = 21,100,00 0 m \ Mos s Landing Harbo

r volum e = 2,200,00 0 m

3

. ETM Estimat e (PM) 0.0431 8 Std . Err . 0.0367 5 Survey Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Jan 200 0 2 4 Fe b 200 0 PE Perio d Start 1 8 Ma y 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Ja n 200 0 PE

Estimat e 0.0104 2 0.0040 3 0.0000 0 0.0396 4 0.0130 4 0.0000 0 0.0000 0 0.00000 0.0086 8 PE

Std . Err . 0.0018 3 0.0029 3 0.0000 0 0.0549 3 0.0168 2 0.00000 0.0000 0 0.0000 0 0.0083 4 +2S E

0.0431 8 -2S E 0.0431 8

F ; 0.1899 7 0.0875 4 0.0400 2 0.1760 7 0.1457 8 • 0.2997 2 0.0250 4 0.0238 2 0.0120 3 F ,

Std . Err . 0.0049 3 0.0025 2 0.0011 2 0.0017 9 0.0018 6 0.0030 6 0.0005 1 0.0069 4 0.0013 2 Larval

Duratio n 3.9 8 3.9 8 3.9 8 3.9 8 3.9 8 3.9 8 3.9 8 3.9 8 3.9 8 Tabl e 6-5b . Fina

l ETM Outpu t fo r Blackey e Gob

y Coryphopterus nicholsi. ETM calculation s based o n Montere

y Ba y volume = 21,100,00 0 m 3, ElkhomSloug

h volum e = 21,100,00 0 m 3 , Mos s Landing Harbo

r volum e = 2,200,00 0 m

3

. ETM Estimat e (PM) 0.0748 8 Std . Err . 0.0475 6

Surve y Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Jan 200 0 2 4 Fe b 200 0 PE Perio d Star t 1 8 May 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Jan 200 0 PE

Estimat e 0.0104 2 0.0381 2 0.00000 0.0396 4 0.0484 2 0.0000 0 0.0000 0 0.00000 0.0504 0 PE

Std . Err . 0.0018 3 0.0276 2 0.00000 0.0549 3 0.0608 1 0.0000 0 0.00000 0.00000 0.0476 3 +2S E

0.0748 8 -2S E 0.0748 8

F i 0.1899 7 0.0875 4 0.0400 2 0.1760 7 0.1457 8 0.2997 2 0.0250 4 0.0238 2 0.0120 3 F i Std . Err . 0.0049 3 0.0025 2 0.0011 2 0.0017 9 0.0018 6 0.0030 6 0.0005 1 0.0069 4 0.0013 2 Larva l

Duratio n 3.9 8 3.9 8 3.9 8 3.9 8 3.9 8 3.9 8 3.9 8 3.9 8 3.9 8 Note : Dat aar e preliminary . E9-053. 9 6-1 2 MLP P 316(b ) Resource Assessmen t 4-28-200 06. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### Fecundit y Hindcas t Mode l (FH) The tota l annua l larva l entrainmen

t fo r blackey e gob y was use

dto estimat

e th e numbe

r of breedin g female s neede dt

o produc e th e numbe

r o f larva e entraine dshown i

n Tabl e 6-6 . Th

e estimate d numbe

r of breedin g female s (FH) whos e fecundit y equal s th e estimate dtota l los s of entraine dlarvae i s calculate dassumin g a n ag e a t maturatio n o f

0. 5 year s anda

n averag e lifespa

n of 3. 6 years . Th e numbe

r of adult female s hindcas t

fro mthe larva

e entraine da

t MLP P combined-cycl e intak

e wa s 1,82 5 (9 0 percent

C.L . = 73 7 t

o 4,524) . Tabl e 6-6 . Annua

l Entrainmen

t an d FH Estimates fo

r Blackey e Gob y Coryphopterus nicholsi: Marc h 1 , 199 9 throug h Fe b 29 , 2000 . Annua l Entrainmen t 16,795,30 0 Annua l Std . Erro r 443,88 5 C V 3 % Fecundity Hindcast

(FH) Estimates for

Blackeye Goby Coryphopterus nicholsi. FH Estimat e 1,825 FH

Std . Erro r 1,007 Uppe r FH 90 % C.L . 4,52 4 Eg g Surviva l 1. 0 Yolk-Sa c

Surviva l 1. 0 Lowe r FH 90 % C.L . 73 7 Larva l

Surviva l 0.73631 3 Egg s

pe r Year 8,06 2 Averag e

Lifespan (yrs ) 3. 6 Ag e a

t Maturatio n 0. 5



### Th e uncertaint

y o f ou r FT/estimat e wa s attribute db y sensitivit y analysi s t

o th e uncertaint

y ofth e model parameter s o f

averag e lifespan , fecundity , an dlarva l survivorship , i

n tha t order . Adul t Equivalen t Los s (AEL) N o independent

estimate o f

surviva l o f blackey e gob y betwee

n ag e o f entrainment

adult s wa s availabl e in th e literature . Th e method s use dto estimat e surviva l base do n tw o gob y specie s (cheekspo t

an dshado w goby ) ar

e discusse din Sectio n 4 . Th e tota l annua l MLP P combined-cycl e entrainmen t o f blackey e gob y (Marc h 199 9 t o March 2000 ) wa s usedt

o estimat e th e numbe

r o f equivalen t adult s theoretically los t

t o th e populatio n show n i n Tabl e 6-7 . Th e estimate dnumbe r o f equivalen t adult s correspondin g to th e numbe r o f larvae tha t woul dhav e been entraine dby th e propose dMLP P combined-cycl e intak

e wa s 16,63 6 (9 0 percent

C . L . = 8,27 7 to 33,436) . W e cannot assum e tha t AEL i s relate dto FH

by afacto r o f tw o sinc e blackey e gob y ar e protogynou s hermaphrodites .

E9-053.9 . 6-1 3 MLP P 316(b ) Resourc e Assessmen t 4-28-200 06. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### Fecundit y Hindcas t Mode l (FH) Th e tota l annua l larva l entrainment

fo r combtoot h blenn y was usedto estimat

e th e numbe

r of breedin g female s neede dt

o produc e the numbe

r of larva e entraine dshow

n i n Tabl e 6-11 . The estimate dnumbe

r o f breedin g female s (FH) whos e fecundit y equal s th e estimate dtota l los s of entraine dlarva

e i s calculate dassumin g a

n ag e a t maturatio n of

2. 0 year s an

da n averag e lifespa

n o f 7. 0 years . Th

e numbe r o f adul t female s hindcas t

fro mth e larva e entraine da

t MLP P combined-cycl e intak

e wa s 9,08 6 (9 0 percen

t C L . = 3,33 5 t

o 24,752) . Tabl e 6-11 . Annua

l Entrainmen

t an dFH Estimates fo

r Unidentifie dBlennies Hypsoblennius spp. : Marc h 1 , 199 9 throug h Februar y 29 , 2000 . Annua l Entrainmen t 16,701,40 0 Annua l Std . Erro r 326,81 8 C V 2 % FH Estimate s fo r

Unidentifie d Blennie s Hypsoblennius spp . FH Estimat e 9,08 6 FH

Std . Erro r 5,53 5 Eg g

Surviva l 1. 0 Uppe r FH 90 % C.L . 24,75 2 Yolk-Sa c Surviva l 1. 0 Lowe r FH 90 % C.L . 3,33 5 Larva l

Surviva l 0.54872 1 Egg s

pe r Year 1,340 Averag e

Lifespan (yrs ) 7. 0 Ag e a

t Maturatio n 2. 0



### The uncertaint

y o f ou r FH estimat e was attribute dby sensitivit y analysi s to th e uncertaint y ofth e model parameter s o f

averag e lifespan , fecundity , an dlarva l survivorship , i

n tha t order . Adul t Equivalen t Los s (AEL) N o independen

t estimate o f

surviva l of combtoot h blenn y betwee n ag e o f entrainment

adult s was availabl e in th e literature . Th e method s use dto estimat e surviva l ar e discusse di

n Sectio n 4 . Th e total annua

l MLP P combine dcycl e entrainmen t of combtoot h blenn y (March 199 9 t

o Marc h 2000 ) wa s use dt

o estimate th e numbe

r o f equivalen t adult s theoretically los t

t o th e populatio n a s shown in Tabl e 6-12 . Th e estimate dnumbe r o f equivalen t adult s correspondin g t

o th e numbe

r of larva e tha t wouldhav e been entraine dby th e propose dMLP P combined-cycl e intak

e was 10,24

7 (9 0 percent

C.L . = 5,09 9 t o 20,593) . The uncertaint y o f ou r AEL estimat e i s mos t affecte d b y th e mode l parameter s o f

early larva

l an dearl y juvenil e survivorship .

E9-053. 9 6-2 0 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.2 9

6. 0 Coolin g Wate r Syste m Impac t Assessmen t Tabl e 6-12 . Annua

l Entrainmen

t an d AEL Estimate s fo

r Unidentified Blennie s Hypsoblennius spp. : Marc h 1 , 199 9 through Februar

y 29 , 2000 . Annua l Entrainmen t 16,701,40 0 Annua l Std . Erro r 85,04 4 

### cv 1 % AEL Estimate s fo

r Unidentifie

dBlennie s Hypsoblennius spp . AEL Estimat e 10,24 7 AEL Std . Erro r 4,34 8

Surviva l Earl y Larva e 0.00570 8 Surviva l

Lat e Larvae I. O

- • • .. • -•>;•.• - -.,.- • Uppe r 90 % C.L . 20,593 Surviva l

Earl y Juv . 1. 0

.; . - ' •;..... - ., v Surviva l

Juv . I 1. 0 Surviva l

Juv . I I 1. 0 Lowe r 90 % C.L . 5,09 9 Surviva l Juv . Il l 1.0 Surviva l

Juv . IV 1. 0 Surviva l

Pre-Recrui t 0.10749 3

Uncertaint y i n ou r

entrainmen t

estimate s ha d relativel y littl e effec t o n th e confidenc e ofth e estimate dAEL. Th e specie s o f

combtoot h blenn y i n ou r stud y are aan d entrainmen t sample s ha s no t

bee n positivel y identifie d(Sectio n 4.5) . Ofth e thre e specie s tha t i t coul d possibl y be , non e suppor t eithe r acommercia l o r

recreationa l fishery valu e an d ther e i s littl e informatio n o n thei r ecologica l rol e i n th e community . Eve n i f w e wer e certai n ofth e specie s identification , ther e ar e n o catc h dat atha t

ca n b e use dt o compar e harves t mortalit y rate s t o entrainmen t mortalit y rate s becaus e ofth e absenc e o f fishery dat afor

an y ofth e thre e possibl e species . N o estimate s o f stoc k siz e o r densit y ar e availabl e fo r an y ofth e thre e specie s t o conver t entrainmen t

mortalit y effect s estimate da s FH

an dAEL value s int o a n estimat e fractiona l populatio n losses . Result s o f

ETM analyse s usin g th e tw o differen t sourc e wate r

volume s sho w tha t

th e powe r

plan t ma y annuall y entrai n approximatel y 1 1 percen t (Tabl e 6-10a ) o r

1 8 percen t

(Tabl e 6-10b ) ofth e combtoot h blenn y larva e fro mth e MLP P sourc e water . Fecundit y hindcas t estimate s indicat e tha t thes e value s o f

FH ma y b e equa l t o predicte d losse s ofth e reproductiv e outpu t o f abou t 3,33 5 t o 24,75 2 adul t

females . A n independen t estimat e o f

AEL yield s apredicte d los s o f 5,09 9 t o 20,59 3 adult s (male s an dfemales combined) . Th e significanc e ofthes e losse s t o th e loca l populatio n o f

adul t combtoot h blenn y i s not known . Th e combtoot h blenny , whic h i s normall y foun dfurthe r

south , ha s recentl y invade d th e harbor/sloug h area , possibl y encourage d b y El

E9-053. 9 6-2 1 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.3 0 r 6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### Nin o current s o

r temperatures . If

thes e effects wer

e vita l t o th e populatio n success , i

t would see mreasonabl e tha

t the y wouldnot

hav e bee n abl e t o coloniz e andgro w to their presen t abundance . 

## 6. 7 Pacifi c Herrin g Pacifi c herrin g ar

e on e ofth e onl

y tw o specie s collecte di

n entrainment

survey s o f

commercia

l o r recreationa

l foo dvalue . Th

e othe r specie s i s whit

e croake r which wer

e only recently collecte d i

n the paire dentrainment-sourc e wate r surveys . The estimate dnumbe r o f entraine dPacifi c herrin g larva e was nearly twic e th e estimate dsourc e wate r numbe r of Pacifi c herrin g larva

e whe n the y occurre d o n th e singl e paire dsourc e wate r an dentrainmen

t samplin g surve

y analyze di

n the previou s report . Th

e resultin g PE

valu e of 0.5 2 (Tabl e 6-13 aan

db ) basedo

n only tw o specimen s probably reflect s amismatch betwee n th e sourc e wate

r locatio n o f

hatchin g Pacific herrin g ro e an

dsourc e wate

r samplin g location s or

depths . Pacifi c herrin g wer e agai n collecte d i n the Februar

y 2000 surveys . Empirica l Transpor t Mode l (ETM) 

### Th e ETM valu e show

n i n Tabl e 6-1 3 fo

r Pacific herrin g base do

n th e Monterey Ba

y sourc e wate

r volum e i s 0.1 3 an

d0.1 3 whe

n th e harbor/slough volum

e i s use di n plac e o f Monterey Ba

y sourc e wate r volume .

E9-053. 9 6-2 2 MLP P 316(b ) Resource Assessmen t 4-28-200 06. 0 Coolin g Wate r Syste m Impac t Assessmen t Table 6-13a . Fina

l ETM Outpu t fo r Pacifi c Herring Clupea pallasi. ETM calculation s based o

n Montere y Ba y volume = 275,000,00 0 m 3, Elkho mSloug

h volum e = 21,100,00 0 m 3 , Mos s Landin g Harbo

r volum e = 2,200,00 0 m

3

. P.3 1

ETM Estimat e (PM) 0.1293 2 Std . Err . 0.0160 8

Surve y Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Sep 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Ja n 200 0 2 4 Feb 200 0 PE Perio d Sta n 1 8 Ma y 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Jan 200 0 PE

Estimat e 0.5234 9 0.00000 0.0000 0 0.0000 0 0.00000 0.0000 0 0.0000 0 0.00000 0.0019 0 PE

Std . Err . 0.2678 7 0.0000 0 0.00000 0.00000 0.00000 0.00000 0.00000 0.0000 0 0.0008 8 +2S E

0.1293 2 -2S E 0.1293 2

F i 0.1200 3 0.0548 9 0.0000 0 0.0288 9 0.00000 0.0455 6 0.0459 3 0.0231 7 0.6815 3 F i

Std . Err . 0.0070 0 0.0014 1 0.0000 0 0.0007 4 0.0000 0 0.0011 7 0.0084 1 0.0060 4 0.0112 9 Larva l

Duratio n 7.5 5 7.5 5 7.5 5 7.5 5 7.5 5 7.5 5 7.5 5 7.5 5 7.5 5 Table 6-13b . Fina

l ETM Outpu t fo r Pacific Herrin g Clupea pallasi. ETM calculation s based o

n Montere y Ba y volume = 21,100,00 0 m 3 , Elkho mSloug

h volum e = 21,100,00 0 m 3 , Mos s Landin g Harbo r volum e = 2,200,00 0 m

3

. ETM Estimat e (PM) 0.1337 1 Std . En . 0.0167 7

Surve y Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Sep 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Jan 200 0 2 4 Fe b 200 0 PE Perio d Star t 1 8 May 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Jan 200 0 PE

Estimat e 0.5234 9 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.0027 7 PE

Std . Err . 0.2678 7 0.00000 0.0000 0 0.0000 0 0.00000 0.0000 0 0.00000 0.00000 0.0013 2 +2S E

0.1337 1 -2S E 0.1337 1

F i 0.1200 3 0.0548 9 0.0000 0 0.0288 9 0.0000 0 0.0455 6 0.0459 3 0.0231 7 0.6815 3 F ,

Std . Err . 0.0070 0 0.0014 1 0.0000 0 0.0007 4 0.0000 0 0.0011 7 0.0084 1 0.0060 4 0.0112 9 Larva l Duratio n 7.5 5 7.5 5 7.5 5 7.5 5 7.5 5 7.5 5 7.5 5 7.5 5 7.5 5 Note : Dat aar e preliminary . E9-053. 9 6-2 3 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.3 2

6. 0 Coolin g Wate r Syste m Impac t Assessmen t Fecundit y Hindcas t Mode l (FH) Th e tota l annua l larva l entrainmen t for Pacifi c herrin g (Marc h 199 9 t o Marc h 2000 ) wa s use d t o estimat e th e numbe r

o f breedin g female s neede d t o produc e th e numbe r o f larva e entraine d show n i n Tabl e 6-14 . Th e estimate d numbe r o f breedin g female s (FH) whos e fecundit y equal s th e estimate dtota l los s o f entraine dlarva e i s calculate d assumin g a n ag e at maturatio n o f

2. 5 year s an da

n averag e lifespan o f

1 1 years . Th e numbe r

o f adul t female s hindcas t

fro mth e larva e entraine da

t MLP P combined-cycl e intak e was 23 5 (9 0 percen t C.L . = 8 0 t o 692) . Table 6-14 . Annua

l Entrainmen

t an d FH Estimate s fo

r Pacifi c Herring Clupea pallasi: Marc h 1 , 1999 through Februar

y 29 , 2000 . Annua l Entrainmen t 4,436,28 0 Annua l Std . Erro r 236,67 1 C V 5 % FH Estimate s fo

r Pacific Herring Clupea pallasi FH Estimat e 23 5 FH

Std . Erro r 15 4 Uppe r FH 69 2 Eg g Surviva l 0. 3 Yol k

Sa c Surviva l 1.0 Lowe r FH 8 0 Larval Surviva l 0.22100 0 Egg s

pe r Year 67,00 0 Averag e

Lifespan (yrs ) 11. 0 Ag e a

t Maturatio n 2. 5

Th e uncertaint y o f

ou r FH estimat e was attribute d b y sensitivit y analysi s t o th e uncertaint y ofth e mode l parameter s o f

averag e lifespan , fecundity , an dlarval survivorship , i n tha t order . Adul t Equivalen t Los s (AEL) Th e method s use dt o estimat e Pacifi c herrin g surviva l ar e discusse d i n Sectio n 4 . Th e tota l annua l MLP P combine dcycl e entrainmen t o f Pacifi c herrin g (Marc h 199 9 t o Marc h 2000 ) wa s use dt o estimat e th e numbe r o f equivalen t

adult s theoreticall y los t

t o th e populatio n a s show n i n Tabl e 6-15 . Th e estimate d numbe r o f equivalen t

adult s correspondin g t o th e numbe r

o f larva e tha t

woul dhav e bee n entraine d b y th e propose d MLP P combined-cycl e intak e wa s 24 3 (9 0 percen t C.L . = 12 1 t o 488) . Th e uncertaint y o f OUT AEL estimat e i s mos t affecte db y th e mode l parameter s o f earl y larva l an d earl y juvenil e survivorship . Uncertaint y i n ou r estimate s o f

entrainmen t

ha drelativel y littl e effec t o n th e uncertaint y ofth e estimate d AEL.

E9-053. 9 6-2 4 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.3 3

6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### Tabl e 6-15 . Annua

l Entrainmen

t an d AEL Estimates fo

r Pacifi c Herrin g Clupea pallasi: March , 1 , 199 9 throug h Februar y 29 , 2000 . Annua l Entrainmen t 4,436,28 0 Annua l Std . Eno r 88,93 4 C V 2 %

AEL Estimate s fo r Pacifi c Herrin g Clupea pallasi

AEL Estimat e 24 3 ..- . • ••• . -.-. . .- . '•:••• • :? : '-iv - AEL Std . Erro r 10 3

Surviva l Earl y Larva e 0.00040 5 Surviva l

Lat e Larva e 1. 0 Uppe r 90 % C.L . 48 8 Surviva l Early Juv . 1. 0 Lowe r 90 % C.L . 12 1 Surviva l

Juv . I 1.0 Surviva l

Juv . I I 1.0 Surviva l

Juv . Il l 1. 0 Surviva l

Juv . I V 1. 0 Surviva l

Pre-Recrui t 0.13500 0



### Result s o f ETM analyse s usin g th e tw o differen t sourc e wate

r volume s sho w tha

t th e powe r plan t ma y annually entrai n approximately 1 3 percen t (Tabl e 6-13 aan

db ) ofth e Pacifi c herrin g larva e fro mth e MLP

P sourc e water . Fecundit

y hindcas t estimate s indicat

e tha t thes e value s o f

FH ma y b e equa l t o predicte dlosse s ofth e reproductiv e outpu t o f abou t 8 0 to 69 2 adul t

females . A

n independen

t estimat e of AEL yield s apredicte dlos s o f

12 1 t o 48 8 adult s (male s andfemale s combined) . 

## 6. 8 Whit e Croake r Whit e croake r larva e hav e been collecte donl

y recentl y i

n th e nin e pair s o f

entrainment

and sourc e water

surveys . Whit

e croaker , a s discusse di

n Sectio n 4 , ar

e on e o f only tw o fish specie s tha t hav e been collecte din entrainmen t survey s tha

t hav e commercia

l or recreational huma

n foo d value . The othe

r specie s i s Pacifi c herrin g a s previously discussed . Empirica l Transpor

t Mode l (ETM) The ETM valu e shown i

n Tabl e 6-1 6 fo

r whit e croake r basedo n th e Monterey Ba

y sourc e wate

r volum e i s 0.01 6 and0.1 3 whe

n th e harbor/sloug h volum

e i s use di n plac e o f Monterey Ba

y sourc e wate

r volume . Result s ofth e ETM analyse s usin g the tw o differen t sourc e water

volume s

E9-053. 9 6-2 5 MLP P 316(b ) Resourc e Assessmen t 4-28-200 06. 0 Coolin g Wate r Syste m Impac t Assessmen t sho w tha t th e powe r

plan t ma y annuall y entrai n approximatel y 2 percen t (Tabl e 6-16a ) an d 1 3 percen t (Tabl e 6-16b ) ofth e whit e croake r larva e fromth e MLP P sourc e water . Table 6-16a . Fina

l ETM Outpu t fo r Whit e Croake r Genyonemus lineatus. ETM calculation s base

d o n Montere

y Ba y volume = 275,000,00 0 m 3, ElkhomSloug

h volum e = 21,100,00 0 m \ Mos s Landing Harbo

r volum e = 2,200,00 0 m

3 ETM Estimat e (PM) 0.0161 1 Std . Err . 0.0154 6 +2S E 0.0161 1 -2S E 0.0161 1 Survey Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Jan 200 0 2 4 Fe b 200 0 PE Perio d Star t 1 8 Ma y 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Ja n 200 0 PE

Estimate . 0.00000 0.0000 0 0.00000 0.00000 0.00000 0.00000 0.0000 0 0.00000 0.0044 9 PE

Std . Err . 0.0000 0 0.0000 0 0.00000 0.00000 0.00000 0.0000 0 0.0000 0 0.0000 0 0.0008 4 F ,

0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.00000 0.0073 0 0.5540 2 0.0214 2 0.4172 5 F ;

Std . Err . 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.0001 6 0.0107 1 0.0031 5 0.0106 8 Larval

Duratio n 8.7 5 8.7 5 8.7 5 8.7 5 8.7 5 8.7 5 8.7 5 8.7 5 8.7 5 Table 6-16b . Fina

l ETM Outpu t Whit e Croake r Genyonemus lineatus. ETM calculation s base

d o n Montere y Ba y volum e = 21,100,00 0 m 3, Elkho mSloug

h volum e = 21,100,00 0 m 3 , Mos s Landing Harbor volum e = 2,200,00 0 m

3 ETM Estimat e (PM) 0.1291 2 Std . Err . 0.0241 6 +2S E 0.1291 2 -2S E 0.1291 2 Surve y Dat e 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Ja n 200 0 2 4 Fe b 200 0 PE Perio d Start 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Jan 200 0 PE

Estimat e 0.0000 0 0.0000 0 0.00000 0.0000 0 0.00000 0.00000 0.0000 0 0.0414 4 PE

Std . Err . 0.0000 0 0.0000 0 0.00000 0.0000 0 0.00000 0.00000 0.0000 0 0.0076 5 F i 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.0073 0 0.5540 2 0.0214 2 0.4172 5 F ,

Std . Err . 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.0001 6 0.0107 1 0.0031 5 0.0106 8 Larva l

Duratio n 8.7 5 8.7 5 8.7 5 8.7 5 8.7 5 8.7 5 8.7 5 8.7 5 Note : Dat aar e preliminary .

E9-053. 9 6-2 6 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.3 5
6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### Fecundit y Hindcas t Mode l (FH) The tota l annua l larva l entrainmen

t fo r whit e croake r (March 199 9 t

o March 2000 ) wa s used t

o estimat e th e numbe

r of breedin g female s neede dt o produc e th e numbe

r o f larva e entraine d show n i n Tabl e 6-17 . Th

e estimate dnumbe

r of breedin g female s (FH) whos e fecundit y equal s the estimate dtota

l los s o f entraine dlarvae i s calculate dassumin g a n ag e a t maturatio n of

2. 0 year s an da n averag e lifespa

n o f 1 2 years . The numbe

r of adul t female s hindcas t

fro mthe larva

e entraine da

t MLP P combined-cycl e intak

e wa s 10 7 (9 0 percen

t C.L . = 4 3 to 270) .

E9-053. 9 6-2 7 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.3 6

6. 0 Coolin g Wate r Syste m Impac t Assessmen t Tabl e 6-17 . Annua

l Entrainmen

t an d FH Estimate s fo

r Whit e Croake r Genyonemus lineatus: Marc h 1 , 199 9 through Februar

y 29 , 2000 . Annua l Entrainmen t 8,627,07 0 Annua l Std . Erro r 404,93 0 

### c v 5 % FH Estimate s fo

r Whit e Croake r Genyonemus lineatus FH Estimat e 107 FH

Std . Erro r 6 0 Uppe r FH 27 0 Eg g Surviva l 1. 0 Yol k

Sa c Surviva l 1. 0 Lowe r FH 4 3 Larva l Surviva l 0.15347 8 Egg s

pe r Yea r 105,00 0 Averag e

Lifespan (yrs ) 12. 0 Ag e a

t Maturatio n 2. 0

Th e uncertaint y o f

ou r FH estimat e wa s attribute d b y sensitivit y analysi s t o th e uncertaint y ofth e model parameter s o f

averag e lifespan , fecundit y an d larva l survivorshi p in tha t order . Adul t Equivalen t Los s (AEL) N o independen t

estimat e o f

surviva l o f

whit e croake r

betwee n ag e o f

entrainmen t

an d adul t

stag e wa s availabl e i n th e literature . 

## 6. 9 Pacifi c Staghor n Sculpi n Th e proportiona l entrainmen t value s for

Pacifi c stagho msculpi n hav e varie d onl y afew tenth s of apercen t

throughou t

th e nin e month s o f

sourc e wate r

an d entrainmen t

studie s a s show n i n Tabl e 6-18 . Th e rang e o f value s fro maPE

o f zer o t o 0.00 9 i n Januar y an d Februar y 200 0 (Tabl e 6-18a ) an d fro mzer o t o 0.0 9 (Tabl e 6-18b) , howeve r di d not correspon d consistentl y t o th e estimate dnumbe r

o f entraine dPacifi c stagho msculpi n larvae . Empirica l Transpor t Mode l (ETM) Th e ETM value s fo r

Pacifi c stagho msculpi n a s show n i n Tabl e 6-1 8 ar e fa r belo w values tha t woul drepresen t

consequentia l intak e effect s o r an y potential fo r

long-ter mpopulatio n declines . Th e ETM valu e base do n Montere y Bay sourc e wate r volum e i s 0.0 4 an d 0.1 2 whe n th e harbor/sloug h sourc e wate r volum e i s use d instea d o f Montere y Ba y sourc e wate r volume . Th e MLP P entrainmen t

impac t evaluatio n give s n o indicatio n o f an y potentia l impact s ofth e ne w combined-cycl e project' s CW S o n th e area' s Pacifi c stagho msculpin .

E9-053. 9 6-2 8 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.3 7

6. 0 Coolin g Wate r Syste m Impac t Assessmen t Table 6-18a . Fina l ETM Outpu t for Pacifi c Stagho mSculpi n Leptocottus armatus. ETM calculation s base d o n Montere y Ba y volum e = 275,000,00 0 m 3, Elkho mSloug h volum e = 21,100,00 0 m 3 , Mos s Landin g Harbo r volum e = 2,200,00 0 m 3

. ETM Estimat e (PM) 0.03640 Std . ErT . 0.0198 2 +2S E 0.0364 0 -2S E 0.0364 0 Surve y Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Jan 200 0 2 4 Fe b 200 0 PE Perio d Star t 1 8 May 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Jan 200 0 PE ' Estimat e 0.0000 0 0.00000 0.00000 0.0000 0 0.0073 8 0.0076 5 0.0017 6 0.0092 6 0.0094 5 PE

Std . Err . 0.00000 0.00000 0.0000 0 0.00000 0.0077 5 0.00540 0.0009 7 0.0045 5 0.00280 Fj

0.0012 8 0.0000 0 0.0000 0 0.0241 8 0.0093 0 0.0536 0 0.4099 3 0.1839 1 0.3177 9 F :

Std . Err . 0.0005 2 0.0000 0 0.0000 0 0.0005 3 0.0015 5 0.0019 8 0.0098 6 0.0111 8 0.0115 0 Larva l

Duratio n 6.3 0 6.3 0 6.3 0 6.3 0 6.3 0 6.3 0 6.3 0 6.3 0 6.3 0 Tabl e 6-18b . Fina l ETM Outpu t for Pacifi c Stagho mSculpi n Leptocottus armatus. ETM Calculation s base d o n Montere y Ba y volum e = 21,100,00 0 m 3 , Elkho mSloug h volum e = 21,100,00 0 m 3 , Mos s Landin g Harbo r volum e = 2,200,00 0 m 3

. ETM Estimat e (PM) 0.1178 9 Std . Err . 0.0299 3 Survey Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Ja n 200 0 2 4 Fe b 200 0 PE Perio d Star t 1 8 May 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Jan 200 0 PE

Estimat e 0.00000 0.0000 0 0.0000 0 0.0000 0 0.0879 7 0.0909 1 0.00490 0.0279 1 0.0251 2 PE

Std . Err . 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.0920 6 0.0625 6 0.0029 8 0.0126 3 0.0086 7 +2S E

0.1178 9 -2S E 0.1178 9

F , 0.0012 8 0.0000 0 0.0000 0 0.0241 8 0.0093 0 0.0536 0 0.4099 3 0.1839 1 0.3177 9 Std . Err .

0.0005 2 0.0000 0 0.0000 0 0.0005 3 0.0015 5 0.0019 8 0.0098 6 0.0111 8 0.0115 0 Larva l

Duratio n 6.3 0 6.3 0 6.3 0 6.3 0 6.3 0 6.3 0 6.3 0 6.3 0 6.3 0 Note : Dat aar e preliminary .

E9-053. 9 6-2 9 MLP P 316(b ) Resource Assessmen t 4-28-200 06. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### Fecundit y Hindcas t Mode l (FH) N o independen t

estimat e o f

surviva l o f

Pacifi c stagho msculpi n betwee n eg g t o entrainmen t ag e was availabl e in th e literature . 

### Adul t Equivalen t Los s (AEL) N o independen t

estimat e o f

surviva l o f

Pacifi c stagho msculpi n betwee n ag e o f entrainmen t

an d th e adul t stag e was availabl e in th e literature . Th e Pacifi c stagho msculpi n sustain s amino r commercia l bai t

fishery i n th e Montere y area . Th e specie s ha s n o recreational fisher y value . Littl e informatio n exist s o n thei r ecologica l role . N o estimate s o f

stoc k siz e o r densit y ar e availabl e t o conver t entrainmen t

effect s estimate d a s FH an dAEL losse s int o estimate s o f

fractional los s to adul t

populations . Result s of

ETM analyse s usin g th e tw o differen t sourc e wate r

volume s sho w tha t

th e powe r

plan t ma y annuall y entrai n approximatel y 4 percen t (Tabl e 6-18a ) an d 1 2 percen t (Tabl e 6-18b ) ofth e Pacifi c stagho msculpi n larva e fromth e MLP P sourc e water . 

## 6.1 0 Hair y Roc k

Cra b Th e proportiona l entrainmen t value s for

hair y roc k

cra b Cancer

jordani hav e varie d onl y afew tenth s of apercen t

throughou t

th e nin e month s o f

sourc e wate r

an d entrainmen t

studie s a s show n in Tabl e 6-19 . Th e PE

value s range d from , zer o t o 0.0009 7 i n Septembe r 199 9 (Tabl e 6 -19a ) an dfro mzer o t o 0.0 1 (Tabl e 6-19b) . Base d o n compute d F ; value s als o show n i n Tabl e 6-19 , th e larges t fraction s o f

hair y roc k

cra b megalop s a

t ris k occurre d i n Septembe r

an d October . 

### Empirica l Transpor t Mode l (ETM) Th e ETM value s for

hair y roc k

cra b a s show n i n Tabl e 6-1 9 ar e fa r belo w value s tha t

woul d represen t consequentia l intak e effect s o r an y potentia l for

long-ter mpopulatio n declines . Th e ETM valu e base do n Montere y Ba y sourc e wate r volum e i s 0.01 8 an d 0.17 7 whe n th e harbor/sloug h sourc e wate r volum e i s use d instea d o f Montere y Ba y sourc e wate r volume . Th e MLP P entrainmen t

impac t evaluatio n give s n o indicatio n o f an y potentia l impact s ofth e ne w combined-cycl e project' s CW S o n th e area' s hair y roc k crab .

E9-053. 9 6-3 0 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.3 9

6. 0 Coolin g Wate r Syste m Impac t Assessmen t Table 6-19a . Fina

l ETM Outpu t Hair y Roc k Crab . ETM

calculation s base d o

n Montere

y Ba y volum e = 275,000,00 0 m 3, ElkhomSloug

h volum e = 21,100,00 0 m 3 , Mos s Landin g Harbo

r volum e = 2,200,00 0 m

3

. ETM Estimat e (PM) 0.0184 2 Std . En- . 0.0638 9 +2S E 0.1462 1 -2S E -0.1093 6 Survey Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Ja n 200 0 2 4 Fe b 200 0 PE

Perio d Start 1 8 May 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Jan 200 0 PE

Estimat e 0.00000 0.00000 0.00000 0.00000 0.0009 7 0.00000 0.0004 6 0.00000 0.00000 PE

Std . Err . 0.00000 0.00000 0.00000 0.00000 0.0009 8 0.00000 0.0004 7 0.00000 0.0000 0 F i 0.00000 0.00000 0.0154 4 0.1655 1 0.3914 9 0.1381 9 0.0797 6 0.1654 8 0.0441 4 F ;

Std . Err . 0.0000 0 0.0000 0 0.0054 9 0.0371 2 0.0352 5 0.0174 1 0.0170 0 0.0231 0 0.0121 3 Larva l

Duratio n 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 Tabl e 6-19b . Fina

l ETM Outpu t fo r Hair y Roc k Crab . ETM

calculation s base d o

n Montere

y Ba y volume = 21,100,00 0 m 3 , ElkhomSloug

h volum e = 21,100,00 0 m 3 , Mos s Landing Harbor

volum e = 2,200,00 0 m

3

. ETM Estimat e (PM) 0.1672 2 Std . Err . 0.1303 7 Surve y Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Jan 200 0 . 2 4 Fe b 200 0 PE Perio d Star t 1 8 Ma y 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Ja n 200 0 PE

Estimat e 0.00000 0.0000 0 0.0000 0 0.00000 0.0105 2 0.00000 0.00600 0.00000 0.00000 PE

Std . Err . 0.00000 0.0000 0 0.0000 0 0.0000 0 0.0105 7 0.0000 0 0.0061 3 0.00000 0.00000 +2S E

0.4279 7 -2S E -0.0935 2
F , 0.0000 0 0.0000 0 0.0154 4 0.1655 1 0.3914 9 0.1381 9 0.0797 6 0.1654 8 0.0441 4 F ,

Std . Err . 0.0000 0 0.0000 0 0.0054 9 0.0371 2 0.0352 5 0.0174 1 0.0170 0 0.0231 0 0.0121 3 Larva l

Duratio n 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 Note : Dat aar e preliminary .

E9-053. 9 6-3 1 MLP P 316(b ) Resourc e Assessmen t 4-28-200 03 .4 0

6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### Fecundit y Hindcastin g Th e tota l annua l larva l entrainmen

t fo r hair y roc k cra b wa s usedt

o estimat e th e numbe

r o f breedin g female s neede dt

o produc e th e numbe

r of megalop s entraine dshown i n Tabl e 6-20 . Th

e estimate dnumbe

r o f breedin g female s (FH) whos e fecundit y equal s th e estimate dtota l los s o f entraine d megalop s i s calculate dassumin g a n ag e a t maturatio n of

1. 5 year s anda

n averag e lifespa n of 4. 8 years . The numbe

r of adul t female s hindcas t

fro mthe megalop s entraine d a t MLP P combined-cycl e intak

e wa s 1,03 9 (9 0 percen

t C.L . = 36 1 t

o 2,987) . Tabl e 6-20 . Annua

l Entrainmen

t an dFH Estimates fo

r Hair y Roc k Crab : Marc

h 1 , 199 9 throug h Februar y 29 , 2000 . Annua l Entrainmen t 1,740,21 0 Annua l Std . Erro r 275,83 9 

### cv 16 %
FH Estimate s Hair y Roc k Crab . FH Estimat e 1,03 9 FH

Std . Erro r 66 7 Eg g

Surviva l 1.0 Megalopa l

Surviva l 0.00065 7 Egg s

pe r Yea r 1,530,90 7 Averag e

Lifespan (yrs ) 4. 8 Ag e a

t Maturatio n 1. 5
Uppe r FH 90 % C.L . 2,98 7 Lowe r FH 90 % C.L . 36 1 

### Th e uncertaint

y o f ou r FH estimat e wa s attribute dby sensitivit y analysi s t

o th e uncertaint

y ofth e model parameter s o f

averag e lifespan , fecundity , an dlarva l survivorship , i

n tha t order . 

## 6.1 1 Yello wRoc k

Cra b Proportiona

l entrainment

value s fo r yello w rock

cra b Cancer anthonyi coul dno t

b e calculate d becaus e they wer

e no t collecte di

n th e paire dsourc e wate

r surve y an dentrainment

surveys . Base d on compute dF

j value s liste di

n Tabl e 6-21 , th e yello w rock cra b megalop s wer

e mos t a t ris k t o entrainment

i n October , mor

e tha n twic e th e exposur

e of an y other month . Empirica l Transpor

t Mode l (ETM) The lac k of co-occurrenc e of

entrainmen

t an dsourc e wate

r sample s containin g yello w cra b megalop s preclude s th e calculatio n o f a n ETM value . Th e MLP P entrainment

impac t evaluatio n

E9-053. 9 6-3 2 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.4 1

6. 0 Coolin g Wate r Syste m Impac t Assessmen t give s n o indicatio n o f

an y potential impact s ofth e ne w combined-cycl e project' s CW S o n th e area' s yello w roc k

crab . Tabl e 6-21a . Fina

l ETM Outpu t Yellow Roc

k Crab . ETM

calculation s based o

n Montere

y Ba y volume = 275,000,00 0 m 3, ElkhomSloug

h volum e = 21,100,00 0 m 3 , Mos s Landin g Harbo

r volum e = 2,200,00 0 m

3

. ETM Estimat e (PM) 0.00000 Survey Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Ja n 200 0 24 Fe b 200 0 PE

Perio d Star t 1 8 May 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Ja n 200 0 Std . Err .

0.0626 3 PE Estimat e 0.00000 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.00000 0.00000 0.0000 0 0.00000 PE

Std . Err . 0.0000 0 0.00000 0.0000 0 0.00000 0.00000 0.0000 0 0.0000 0 0.00000 0.00000 +2S E

0.1252 6 -2S E -0.1252 6
F i 0.0000 0 0.0000 0 0.0154 4 0.1655 1 0.3914 9 0.1381 9 0.0797 6 0.1654 8 0.0441 4 F

i Std . Err . 0.0000 0 0.0000 0 0.0054 9 0.0371 2 0.0352 5 0.0174 1 0.0170 0 0.0231 0 0.0121 3 Larva l

Duratio n 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 Tabl e 6-2 1 b . Fina

l ETM Outpu t fo r Yellow Roc

k Crab . ETM

calculation s base d o

n Montere

y Ba y volume = 21,100,00 0 m 3, Elkho mSloug

h volum e = 21,100,00 0 m 3 , Mos s Landin g Harbo

r volum e = 2,200,00 0 m

3

. ETM Estimat e (PM) 0.0000 0 Std . Err . 0.0626 3 +2S E 0.1252 6 -2S E -0.1252 6 Surve y Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Ja n 200 0 2 4 Fe b 200 0 PE

Perio d Start 1 8 Ma y 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Ja n 200 0 PE

Estimat e 0.00000 0.0000 0 0.00000 0.00000 0.00000 0.00000 0.0000 0 0.00000 0.00000 PE

Std . Err . 0.0000 0 0.00000 0.00000 0.0000 0 0.00000 0.00000 0.0000 0 0.00000 0.0000 0 F

i 0.00000 0.0000 0 0.0154 4 0.1655 1 0.3914 9 0.1381 9 0.0797 6 0.1654 8 0.0441 4 F

i Std . Err . 0.0000 0 0.0000 0 0.0054 9 0.0371 2 0.0352 5 0.0174 1 0.0170 0 0.0231 0 0.0121 3 Larva l

Duratio n 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 45.0 0 Note : Dat aar e preliminary .

E9-053. 9 6-33 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.4 2 

# r
6. 0 Coolin g Wate r Syste m Impac t Assessmen t



### Fecundit y Hindcastin g Th e tota l annua l larva l entrainmen

t fo r yello w rock

cra b wa s use dto estimate th e numbe r o f breedin g female s neededt

o produc e th

e numbe r of megalop s entraine dshown i n Tabl e 6-22 . Th e estimate dnumbe

r of breedin g female s (FH) whos e fecundit y equal s the estimate dtota l los s o f entraine dmegalop s i s calculate dassumin g a n ag e a t maturatio n o f

1. 5 year s an da n averag e lifespa n of 4. 8 years . Th

e numbe r p f adul t female s hindcas t

fro mth e megalop s entraine d a t MLP P combined-cycl e intak

e wa s 13 1 (9 0 percen

t C.L . = 4 6 t

o 374) . Tabl e 6-22 . Annua

l Entrainmen

t an dFH Estimates fo

r Yello w Roc k Crab : Marc

h 1 , 199 9 throug h Februar y 29 , 2000 . Annua l Entrainmen t 462,44 6 Annua l Std . Erro r 68,00 6 

### c v 15 % FH Estimates . FH Estimat e 13 1 FH

Std . Erro r 8 4 Eg g

Surviva l 1.0 Megalopa l

Surviva l 0.00081 7 Egg s

pe r Yea r 2,600,00 0 Averag e

Lifespa n (yrs ) 4. 8 Ag e a

t Maturatio n 1. 5

Uppe r FH 90 % C.L : 37 4 Lowe r FH 90 % C.L . 4 6 

### Th e uncertaint

y o f ou r FH estimate wa s attribute db y sensitivit y analysi s t o th e uncertaint y ofth e model parameter s o f

averag e lifespan , fecundity , an dlarva l survivorship , i

n tha t order . 

## 6.1 2 Brow n Roc k

Cra b Proportiona

l entrainmen

t value s fo r brow n roc

k cra b Cancer antennarius coul dnot

b e calculate d becaus e the

y wer e no t collecte di

n th e paire dsourc e wate

r an ddaytim e entrainmen

t surveys . Base do n compute dF

i value s liste di

n Tabl e 6-23 , brown rock

cra b megalop s wer

e mos t a t ris k t o entrainmen

t i n October . Empirica l Transpor t Mode l (ETM) The lac k o f co-occurrenc e o f

entrainmen

t an dsourc e sample s containin g brow n rock cra b megalop s preclude s the calculatio n ofa n ETM value . The MLP

P entrainment

impac t evaluatio n
E9-053. 9 6-3 4 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.4 3

6. 0 Coolin g Wate r Syste m Impac t Assessmen t give s n o indicatio n o f

an y potentia l impact s ofth e ne w combined-cycl e project' s CW S o n th e area' s brow n roc k

crab . Tabl e 6-23a . Fina

l ETM Outpu t fo r Brown Roc

k Crab . ETM

calculation s base d o

n Montere

y Ba y volume = 275,000,00 0 m 3, ElkhomSloug

h volum e = 21,100,00 0 m \Mos s Landing Harbo r volum e = 2,200,00 0 m

3

. ETM Estimat e (PM) 0.00000 Surve y Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Jan 200 0 2 4 Fe b 200 0 PE

Perio d Start 1 8 May 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Ja n 200 0 Std . Err .

0.0626 3 PE Estimat e 0.0000 0 0.00000 0.0000 0 0.00000 0.00000 0.0000 0 0.00000 0.00000 0.0000 0 PE

Std . Err . 0.0000 0 0.0000 0 0.00000 0.0000 0 0.0000 0 0.00000 0.0000 0 0.0000 0 0.0000 0 +2S E

0.1252 6 -2S E -0.1252 6

F ; 0.0000 0 0.00000 0.0154 4 0.1655 1 0.3914 9 0.1381 9 0.0797 6 0.1654 8 0.0441 4 F i

Std . Err . 0.00000 0.0000 0 0.0054 9 0.0371 2 0.0352 5 0.0174 1 0.01700 0.0231 0 0.0121 3 Larva l

Duratio n 43.3 0 43.3 0 43.3 0 43.3 0 43.3 0 43.3 0 43.3 0 43.3 0 43.3 0 Tabl e 6-23b . Fina

l ETM Outpu t fo r Brow n Roc k Crab . ETM

calculation s based o

n Montere

y Ba y volum e = 21,100,00 0 m 3, Elkhor n Slough volum

e = 21,100,00 0 m 3 , Mos s Landing Harbo

r volum e = 2,200,00 0 m

3

. ETM Estimat e (PM) 0.0000 0 Surve y Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Ja n 200 0 2 4 Fe b 200 0 PE

Perio d Star t 1 8 May 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Ja n 200 0 Std . Err .

0.0626 3 PE Estimat e 0.0000 0 0.0000 0 0.00000 0.0000 0 0.0000 0 0.00000 0.0000 0 0.00000 0.00000 PE

Std . Err . 0.0000 0 0.00000 0.0000 0 0.0000 0 0.00000 0.0000 0 0.0000 0 0.0000 0 0.0000 0 +2S E

0.1252 6 -2S E -0.1252 6

F ; 0.00000 0.0000 0 0.0154 4 0.1655 1 0.3914 9 0.1381 9 0.0797 6 0.1654 8 0.0441 4 F i

Std . Err . 0.0000 0 0.0000 0 0.0054 9 0.0371 2 0.0352 5 0.0174 1 0.0170 0 0.0231 0 0.0121 3 Larva l

Duratio n 43.3 0 43.3 0 43.3 0 43.3 0 43.3 0 43.3 0 43.3 0 43.3 0 43.3 0 Note : Dat aare preliminary . E9-053. 9 6-3 5 MLP P 316(b ) Resource Assessmen t 4-28-200 06. 0 Coolin g Wate r Syste m Impac t Assessmen t



### Fecundit y Hindcastin g The tota l annua l larva l entrainmen

t fo r brown roc

k cra b wa s use dto estimat

e th e numbe

r of breedin g female s neede dto produc e th e numbe r of megalop s entraine dshow n i n Tabl e 6-24 . Th e estimate dnumbe

r o f breedin g female s (FH) whos e fecundit y equal s th e estimate dtota l los s of entraine dmegalop s i s calculate d assumin g a n ag e a t maturatio n o f

1. 5 year s anda

n averag e lifespa n of 5. 5 years . Th

e numbe r of adult female s hindcas t

fro mth e megalop s entraine d a t MLP P combined-cycl e intak

e wa s 20 9 (9 0 percen

t C.L . = 7 1 t

o 612) . Tabl e 6-24 . Annua

l Entrainmen

t an dFH Estimates fo

r Brow n Roc k Crab : Marc

h 1 , 199 9 throug h Februar y 29 , 2000 . Annua l Entrainmen t 784,55 4 Annua l Std . Erro r 198,93 4 

### c v 25 %

FH Estimates . FH Estimat e 20 9 FH

Std . Erro r 13 7 Eg g

Surviva l 1. 0 Megalopa l

Surviva l 0.00106 9 Egg s

pe r Yea r 1,756,45 0 Averag e

Lifespa n (yrs ) 5. 5 Ag e a

t Maturatio n 1. 5

' - • > • . •-•-*'•-. . ' : ' • ' Uppe r FH 90 % C.L . 61 2 Lowe r FH 90 % C.L . 7 1 

### Th e uncertaint

y o f ou r FH estimat e wa s attribute dby sensitivit y analysi s to th e uncertaint y ofth e model parameter s o f

averag e lifespan , fecundity , an dlarva l survivorship , in tha

t order . 

## 6.1 3 Dungenes s Cra b ETM calculation s wer

e no t done fo r dungenes s cra

b Cancer magister. Ther

e wer e n o dungenes s cra b megalop s collecte di

n the sourc e wate

r survey s fro

mJun e 199 9 throug h Februar y 2000 . The y wer e collecte di

n entrainmen

t sample s fro

mth e ne w combined-cycl e unit s intak e befor e th e sourc e wate

r survey began . W

e ma y collec t dungenes s cra

b megalop s i

n th e March an

d Apri l 200 0 surveys .

E9-053. 9 6-3 6 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.4 5

6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### Fecundit y Hindcastin g The tota l annua l larva l entrainmen

t fo r dungenes s cra

b wa s use dto estimate th e numbe r o f breedin g female s neededt

o produc e th

e numbe r of megalop s entraine dshow n i n Tabl e 6-25 . Th e estimate dnumbe

r of breedin g female s (FH) whos e fecundit y equal s th e estimate dtota l los s of entraine dmegalop s i s calculate dassuming a n ag e a t maturatio n of

2. 0 year s an

da n averag e lifespa n of 6. 0 years . Th

e numbe r o f adul t female s hindcas t

fro mth e megalop s entraine d a t MLP P combined-cycl e intak

e wa s 16 7 (9 0 percent

C.L . = 5 6 t

o 496) . Tabl e 6-25 . Annua

l Entrainmen

t an dFH Estimates fo

r Dungenes s Crab : Marc

h 1 , 199 9 throug h Februar y 29 , 2000 . Annua l Entrainmen t 335,18 0 Annua l Std . Erro r 59,59 4 

### cv 18 % FH Estimates . FH Estimat e 16 7 FH

Std . Erro r 11 0 Eg g

Surviva l 1.0 Megalopa l

Surviva l 0.00080 2 Egg s

pe r Yea r 1,250,00 0 Averag e

Lifespa n (yrs ) 6. 0 Ag e a

t Maturatio n 2. 0
Uppe r FH 90 % C.L . 49 6 Lowe r FH 90 % C.L . 5 6 

## 6.1 4 Re d Roc k

Cra b The proportiona

l entrainmen

t valu e of 0.9 5 (Tabl e 6-26 aan

db ) fo r re drock cra b Cancer productus wa s compute dfro mthe singl e occasio n whe

n it s megalop s wer

e collecte di

n bot h entrainment

andsourc e water

samples . Th e compute dF ; 

### value s liste di n Tabl e 6-2 6 indicat e tha t redrock cra b ar e a t risk o f entrainmen

t fro mAugus t t o February , wit

h pea k exposure i

n October . Empirica l Transpor

t Mode l (ETM) The ETM value s fo r redrock cra b a s shown i

n Tabl e 6-2 6 ar

e fa r belo w value s tha

t would represent consequentia

l intak e effects o r an y potentia l fo r long-ter mpopulatio n declines . Th e ETM valu e base do

n Monterey Ba

y sourc e wate

r volum e i s 0.0 4 an dals o 0.04 when th e harbor/sloug h sourc e wate

r volum e i s use dinstea

dof Monterey Ba

y sourc e water

volume . Th

e MLP P entrainmen

t impact evaluatio n give s no indicatio n of an y potentia l impact s ofth e ne

w combined-cycl e project' s CWS o n the area' s redroc

k crab .

E9-053. 9 6-3 7 MLP P 316(b ) Resource Assessmen t 4-28-200 06. 0 Coolin g Wate r Syste m Impac t Assessmen t P.4 6

Table 6-26a- . Final ETM

Outpu t for Re d Roc k

Crab . ETM

calculation s base d o n Montere y Ba y volum e = 275,000,00 0 m 3 , Elkho mSloug h volum e = 21,100,00 0 m 3 , Mos s Landin g Harbo r volum e = 2,200,00 0 m 3

. ETM Estimat e (PM) 0.0441 4 Surve y Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Jan 200 0 2 4 Fe b 200 0 PE

Perio d Start 1 8 Ma y 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Jan 200 0 Std . Err .

0.0614 4 PE Estimat e 0.0000 0 0.0000 0 0.00000 0.0000 0 0.00000 0.0000 0 0.0000 0 0.0000 0 0.9502 3 PE

Std . Err . 0.00000 0.0000 0 0.00000 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.00000 1.3438 3 +2S E

0.1670 2 -2S E -0.0787 5

F , 0.0000 0 0.0000 0 0.0154 4 0.1655 1 0.3914 9 0.1381 9 0.0797 6 0.1654 8 0.0441 4 F ,

Std . Err . 0.0000 0 0.0000 0 0.0054 9 0.0371 2 0.0352 5 0.0174 1 0.0170 0 0.0231 0 0.0121 3 Larva l

Duratio n 97.0 0 97.0 0 97.0 0 97.0 0 97.0 0 97.0 0 97.0 0 97.0 0 97.0 0 Tabl e 6-26b . Fina l ETM

Outpu t for Re d Roc k

Crab . ETM

calculation s base d o n Montere y Ba y volum e = 21,100,00 0 m 3 , Elkho mSloug h volum e = 21,100,00 0 m 3 , Mos s Landin g Harbo r volum e = 2,200,00 0 m 3

. ETM Estimat e (PM) 0.0441 4 Std . Err . 0.0614 4 +2S E 0.1670 2 -2S E -0.0787 5 Survey Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Ja n 200 0 2 4 Fe b 200 0 PE Perio d Start 1 8 Ma y 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Ja n 200 0 PE

Estimat e 0.00000 0.00000 0.00000 0.00000 0.00000 0.0000 0 0.00000 0.00000 0.9502 3 PE

Std . Err . 0.0000 0 0.00000 0.0000 0 0.00000 0.00000 0.00000 0.00000 0.00000 1.3438 3 F i 0.0000 0 0.0000 0 0.0154 4 0.1655 1 0.3914 9 0^1381 9 0.0797 6 0.1654 8 0.0441 4 F ,

Std . Err . 0.0000 0 0.0000 0 0.0054 9 0.0371 2 0.0352 5 0.0174 1 0.0170 0 0.0231 0 0.0121 3 Larva l

Duratio n 97.0 0 97.0 0 97.0 0 97.0 0 97.0 0 97.0 0 97.0 0 97.0 0 97.0 0 Note : Dat aar e preliminary .

E9-053. 9 6-3 8 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.4 7

6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### Fecundit y Hindcastin g The tota l annua l megalopa

l entrainmen

t fo r redroc k cra b wa s usedt

o estimat e th e numbe

r o f breedin g female s neede dto produc e the numbe r o f megalop s entraine dshown i n Tabl e 6-27 . The estimate dnumbe

r o f breedin g female s (FH) whos e fecundit y equal s the estimate dtota l los s o f entraine dmegalop s i s calculate dassumin g a n ag e a t maturatio n of

1. 5 year s an da n averag e lifespa n o f 4. 8 years . The numbe

r of adult female s hindcas t

fro mth e megalop s entraine d a t MLP P combined-cycl e intak

e wa s 6 0 (9 0 percent

C.L . = 2 0 to 181) . Tabl e 6-27 . Annua

l Entrainmen

t an dFH Estimates fo

r Re d Roc k Crab : Marc

h 1 , 199 9 throug h Febmar y 29 , 2000 . Annua l Entrainmen t 246,36 3 Annua l Std . Erro r 64,23 7 

### c v 26 %

FH Estimates . FH Estimat e 6 0 FH

Std . Erro r 4 0 Eg g

Surviva l 1. 0 Megalopa l

Surviva l 0.00165 8 Egg s

pe r Yea r 1,492,50 0 Averag e

Lifespan (yrs ) 4. 8 ' Ag e a

t Maturatio n 1. 5
Uppe r FH 90 % C.L . 18 1 Lowe r FH 90 % C.L . 2 0 

## 6.1 5 Slende r Roc k

Cra b Th e proportiona

l entrainmen

t value s fo r slende r roc k cra b Cancer gracilis i s fro

masingl e survey in December , whe

n the y wer e collecte di

n bot h entrainmen

t andsourc e samples . Th

e PE value s o f 0.00 9 (Tabl e 6-28a

) an d0.1 1 (Tabl e 6-2 8 b ) wer

e use dto calculate th e ETM value s i n Tabl e 6-28 . However , asingl e estimate dproportiona l entrainmen

t valu e doe s provid e arobus t ETM estimate . Empirica l Transpor

t Mode l (ETM) The ETM value s fo r slende r roc k cra b a s show n i n Tabl e 6-2 8 ar

e fa r belo w value s tha

t woul d represent consequentia

l intak e effects or

an y potentia l fo r long-ter mpopulatio n declines . The ETM valu e base don Monterey Ba y sourc e wate

r volum e i s 0.0 3 an

d0.0 8 whe

n th e harbor/sloug h sourc e water volum e i s use dinstea

dof Montere y Ba y sourc e wate

r volume . Th

e MLP P entrainment

impac t evaluatio n give s n o indicatio n o f an y potentia l impact s ofth e new combined-cycl e project' s CWS o n the area' s slende

r roc k crab . E9-053. 9 6-3 9 MLP P 316(b ) Resource Assessmen t 4-28-200 06. 0 Coolin g Wate r Syste m Impac t Assessmen t

Table 6-28a . Fina

l ETM Outpu t Slende r Roc k Crab . ETM

calculation s base d o

n Montere

y Ba y volume = 275,000,00 0 m 3 , Elkho mSlough volum

e = 21,100,00 0 m 3 , Mos s Landin g Harbo

r volum e = 2,200,00 0 m

3

. P.4 8

ETM Estimat e (PM) 0.0253 1 Survey Dat e 17Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Jan 200 0 2 4 Fe b 200 0 PE

Perio d Start 1 8 Ma y 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Ja n 200 0 Std . Err .

0.0666 2 PE Estimat e 0.00000 0.00000 0.0000 0 0.00000 0.0000 0 0.00000 0.0091 4 0.00000 0.00000 PE

. Std . Err . 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.00000 0.00000 0.0113 2 0.0000 0 0.0000 0 +2S E

0.1585 5 •2S E -0.1079 2

F , 0.00000 0.00000 . 0.0154 4 0.1655 1 0.3914 9 0.1381 9 0.0797 6 0.1654 8 0.0441 4 F ,

Std . Err . 0.0000 0 0.0000 0 0.0054 9 0.0371 2 0.0352 5 0.0174 1 0.0170 0 0.0231 0 0.0121 3 Larva l

Duratio n 41.6 0 41.6 0 41.6 0 41.6 0 41.6 0 41.6 0 41.6 0 41.6 0 41.6 0 Tabl e 6-28b . Fina

l ETM Outpu t fo r Slende r Roc k Crab . ETM

calculation s based o

n Montere

y Ba y volume = 21,100,00 0 m \ Elkho mSloug h volum e = 21,100,00 0 m 3 , Mos s Landin g Harbo

r volum e = 2,200,00 0 m

3

. ETM Estimat e (PM) 0.0790 3 Std . Err . 0.0604 4 Survey Dat e 1 7 Ju n 199 9 1 2 Ju l 199 9 1 2 Au g 199 9 1 6 Se p 199 9 1 4 Oc t 199 9 1 8 No v 199 9 2 9 De c 199 9 2 0 Ja n 200 0 2 4 Fe b 200 0 PE Perio d Star t 1 8 Ma y 199 9 1 8 Ju n 199 9 1 3 Ju l 199 9 1 3 Au g 199 9 1 7 Se p 199 9 1 5 Oc t 199 9 1 9 No v 199 9 3 0 De c 199 9 2 1 Ja n 200 0 PE

Estimat e 0.00000 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.0000 0 0.1067 2 0.0000 0 0.00000 PE

Std . Err . 0.00000 0.0000 0 0.00000 0.0000 0 0.0000 0 0.0000 0 0.12820 0.00000 0.00000 +2S E

0.19990 -2S E -0.0418 4

^ 0.0000 0 0.0000 0 0.0154 4 0.1655 1 0.3914 9 0.1381 9 0.0797 6 0.1654 8 0.0441 4 F (

Std . Err . 0.0000 0 0.0000 0 0.0054 9 0.0371 2 0.0352 5 0.0174 1 0.0170 0 0.0231 0 0.0121 3 Larva l

Duratio n 41.6 0 41.6 0 41.6 0 41.6 0 41.6 0 41.6 0 41.6 0 41.6 0 41.6 0 Note : Dat aar e preliminary .

E9-053. 9 6-40 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.4 9

6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### Fecundit y Hindcastin g Th e tota l annua l larva l entrainmen

t fo r slende r roc k cra b wa s use dt

o estimate th e numbe

r of breedin g female s neededt

o produc e the numbe

r of larva e entraine dshown i

n Tabl e 6-29 . Th

e estimate dnumbe

r of breedin g female s (FH) whos e fecundit y equal s the estimate dtota l los s of entraine dmegalop s i s calculate dassumin g a n ag e a t maturatio n o f

1. 0 yea r anda n averag e lifespa n o f 3. 0 years . The numbe

r of adul t female s hindcas t

fro mth e megalop s entraine d a t MLP P combined-cycl e intak

e wa s 23 9 (9 0 percent

C.L . = 7 7 t

o 740) . Tabl e 6-2 9 Annua l Entrainmen

t an dFH Estimates fo

r Slende r Roc k Crab : Marc

h 1 , 199 9 throug h Februar y 29 , 2000 . Annua l Entrainmen t 185,75 7 Annua l Std . Erro r 47,90 9 

### c v 26 % /"//Estimate s Slende r Roc k Crab . FH Estimat e 23 9 FH

Std . Erro r 16 4 Eg g

Surviva l 1. 0 Megalopa l

Surviva l 0.00139 8 Egg s

pe r Yea r 555,58 3 Averag e

Lifespa n (yrs ) 3. 0 Ag e a

t Maturatio n 1. 0
Uppe r FH 90 % C.L . 74 0 Lowe r FH 90 % C.L . 7 7 

### The uncertaint

y o f ou r FH estimat e wa s attribute db y sensitivit y analysi s t

o th e uncertaint

y ofth e mode l parameter s o f

averag e lifespan , fecundity , and larva l survivorship , i

n tha t order . 

## 6.1 6 Summar

y of Entrainmen t Effect s Th e concentration s offis h an

dcra b larvae collecte da

t the ne w combined-cycl e intak

e wer e use d t o estimat e entrainmen

t losse s by extrapolatin g t

o bot h arepresentativ e number s o f adult s an d by th e fractiona

l larva l entrainmen

t los s to th e adult

population . Thre e independent models , fecundit y hindcas t (FH), adult

equivalen t los s (AEL) an

dempirica l transpor t model (ETM), wer

e employedi

n calculatin g entrainmen

t losses . Result s fro

mth e thre e model s ar

e summarize d wher e applicabl e by specie s o f

fishe s an dcrab s i n Tabl e 6-30 aandb , respectively . Estimate d losse s of adul t ba y goby an dcombtoot

h blennies , th e highes t

losse s identifie di

n ou r assessmen

t o f entrainmen

t effects , indicat

e apotentia

l fo r loca l populatio n level impacts . Howeve r thes e estimate dtheoretica

l losse s ar e basedo n AEL an dFH modeling result s usin g generalize d larva l mortalit y informatio n tha

t ma y o r ma y not accurately represen

t th e specifi c species ' larva l

E9-053. 9 6-4 1 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.5 0

6. 0 Coolin g Wate r Syste m Impac t Assessmen t surviva l rates . I n th e cas e ofth e blenny , w e ar e uncertai n whic h o f possibl y thre e combtooth blenn y specie s w e hav e collected . Ou r study' s modelin g results , a s summarize d i n Tabl e 6-30 , generall y demonstrat e bot h lo w level s o f entrainmen t

effect s an d i n theor y commensuratel y lo w potential s for

advers e populatio n leve l impacts . Informatio n abou t

th e siz e ofth e species ' adul t fish population s i s require d t o conver t th e FH, AEL, an dETM

estimate s int o comparabl e unit s o f fishe s depend s o n dat adescribing . However , th e majority o f

tax afoun di n ou r

stud y ar e no t

commerciall y o r

recreationall y harvested . Th e absenc e o f

apopulatio n assessmen t o r an y fisher

y dat afor thi s specie s w e coul d not provid e an y contex t for th e estimates . Fo r

example , eg g an d larva l mortalit y dat afor blackey e gob y allowe d th e applicatio n o f

multipl e assessmen t

approaches , bu t

becaus e th e specie s i s no t harveste d o r monitore dat

th e populatio n leve l th e losse s canno t b e compare d t o an y standin g stoc k o f blackey e goby . Fo r thos e specie s wit h both FH an dAEL estimate d losses , th e mode l result s can b e compare d directl y usin g th e relationshi p AEL = 2FH. Thi s conversio n require s that age s o f AEL an dFH individual s ar e equa l in a50:5 0 se x ratio . Result s fo r abundan t tax atha t wer e i n clos e agreemen t with th e relationshi p 2FH = AEL provid e som e assuranc e tha t th e parameter s use d in th e model s wer e representativ e for

th e stud y are apopulations . The y als o increas e confidenc e tha t th e assessment s o f

effect s o n thes e population s ar e reasonabl y accurate . Two example s wer e whit e croake r an dth e Pacifi c herring . Fo r th e abundan t

tax awithou t

availabl e lif

e histor y information , lengt h measurement s o f larva e fromth e entrainmen t

sample s provide d som e insigh t int o thei r larva l lif e histor y an d ecology . Th e length range s for

mos t ofth e entraine d abundan t larva l fish tax aindicat e tha t thei r exposur e t o entrainmen t

occur s ove r

arelativel y shor t

tim e perio d durin g thei r

development . Averag e length s wer e smal l demonstratin g tha t the y wer e exposed t o entrainmen t for abrie f perio d durin g thei r larva l development . Th e lac k ofthes e late r

developmenta l stage s indicate s larva l behavio r tha t remove s the mfro mrisk

o f entrainmen t

a s the y develo p (e.g. , settlemen t t o benthi c habitat s o r migratio n int o deepe r

area s awa y fro mth e intake) . Abundan t larva l tax atha t

ar e no t commerciall y o r

recreationall y harveste d ar e primaril y smal l ba y an d sloug h fishes . A s migh t b e expecte d du e t o th e shallo w water , shorelin e intak e location , severa l ofthes e tax aar e entraine di n relativel y hig h numbers , resultin g i n larg e AEL an d FH estimate s (Tabl e 6-30) . Fo r example , losse s o f

approximatel y 300 , 00 0 unidentifie d gobie s an d 1,450,00 0 ba y gob y wer e estimate dusin g th e FH an d AEL models , respectively . Howeve r ETM value s for th e tw o specie s wer e relativel y smal l (unidentifie d gobie s = 0.02 6 [Tabl e 6-la ] an d 0.21 4 [Tabl e 6-lb ] an dba y gob y = 0.03 9 [Tabl e 6-3a ] an d 0.10 6 [Tabl e 6-3b]) .

E9-053. 9 6-4 2 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.5 1

6. 0 Coolin g Wate r Syste m Impac t Assessmen t Result s fromth e presen t

stud y indicat e effect s o n commerciall y an d redreationall y harveste d specie s with pelagi c distribution s suc h a s Pacifi c herrin g an d whit e croake r ar e minimal . Fo r case s wher e w e wer e abl e t o appl y al l thre e assessmen t approaches , th e effect s detecte d wer e relativel y small , appeare dt o b e localized , an d thu s coul d no t affec t th e overal l adul t

populations . Ther e was ver y littl e availabl e informatio n o n th e demograph y o f ou r mos t abundan t tax atha t wer e not commerciall y o r

recreationall y important . Thi s lac k o f lif e histor y infonnatio n limite d th e applicatio n o f

assessmen t

model s t o th e ETM. I n summary , i t

i s unlikel y tha t

population s o f

fishe s an d crab s wil l t o b e adversel y affecte d b y th e ne w combined-cycl e coolin g wate r intake . Som e ar e commerciall y importan t tax awith pelagi c egg s an dwidesprea dpopulation s (e.g. , whit e croaker) . Thei r assessment s resulte d i n eithe r lo w estimate dlarva l mortalitie s o r smal l number s o f

adul t losse s t o thei r

populations . Othe r widesprea dspecie s als o ha dlo w number s o f estimate d adul t

equivalen t

losse s t o thei r population s an dlo w estimate dlarva l mortality , with population s that ar e distribute d wel l beyon d th e zon e o f

influenc e o f

MLPP , suc h a s Pacifi c herrin g an d Pacifi c stagho msculpin . Th e model s use dfor

entrainmen t

assessmen t

considere d function s critica l t o th e lif e histor y o f th e abundan t

tax ao f fishe s an dcrabs . Thes e model s wer e applie d both a t th e poin t o f entrainmen t

for estimatin g th e number s o f individual s entraine d an d als o in th e adjacen t Elkho m Slough , Mos s Landin g Harbor , an dMontere y Bay area s for estimatin g th e populatio n o f inference . Th e are aaroun dMLP P include s nurser y an d feedin g area s for man y specie s o f

ou r abundan t taxa , particularl y gob y species . Thes e area s als o exten d awa y fro mMLP P zon e o f influence . I n th e cas e o f

Pacifi c herrin g th e cente r o f spawnin g biomas s i s locate d wel l nort h o f Montere y Bay . Lengt h measurement s o f larva e indicat e tha t

mos t o f th e abundan t

tax awer e produce dlocall y an dthu s ar e expose d t o entrainmen t for arelativel y shor t

perio d oftim e durin g thei r larva l development . Thes e result s indicat e tha t entrainmen t

effect s appea r

t o b e limite d t o localize deffect s o n ba y an dsloug h species . Therefore , th e potentia l for entrainmen t

damag e t o commerciall y o r

recreationall y sourc e wate r bod y specie s i s low .

E9-053. 9 6-43 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.5 2

6. 0 Coolin g Wate r Syste m Impac t Assessmen t Table 6-30 . Summar

y o f Estimate d MLP

P New Combined-cycl e Entrainmen t Effects fo r Abundan t Fishe s an dCance r Crab s Based o

n ETM, FH, an

d AEL Model s Usin g Entrainmen t an d Sourc e Wate

r Larva l Concentration s an

d Montere y Bay , Mos s Landing Harbor , an d Elkhom Sloug h Volume s (Marc

h 1999-Februar

y 2000) . (a ) Fishe s

Unidentifie dgobie s Ba y gob y Blackey e gob y Longjaw mudsucke r Hypsoblennius spp . Pacifi c herrin g Whit e croake r Pacifi c staghorn sculpi n Tota l Entraininen t 2. 7 x 10 s 1. 5 x 10 8 1. 7 x 10 ' 8. 0 x IO 6 1. 7 x 10

7 4. 4 x IO6 8. 6 x 10 " * FH

300,00 6 * 1,82 5 49 7 9,08 6 23 5 10 7 * AEL

* 1,045,58 8 16,63 6 * 10,24 7 24 3 * * £7W >

0.02 6 0.03 9 0.04 3 0.05 2 0.11 1 0.12 9 0.01 6 0.03 6 ETM*)

0.10 7 0.21 4 0.07 5 0.08 9 0.18 2 0.13 4 0.12 9 0.11 8

Unidentifie d gobie s Ba y gob y Blackey e gob y Longjaw mudsucke r Hypsoblennius spp . Pacifi c herrin g Whit e croake r Pacifi c staghorn sculpi n FH 300,00 6 * 1,82 5 49 7 9,08 6 23 5 10 7 * Tota l

Entrainment 2. 7 x 10 8 1. 5 x 10 8 1.7 x IO

7 8. 0 x 10 6 1.7 x IO

7 4. 4 x IO

6 8. 6 x IO

6 1.0 x IO

7 Egg Surviva l

• * * * * 0. 3 * * Yolk-sa c

Surviva l Larva e

Surviva l 0.6 8 * 0.7 4 0.4 5 0.5 5 0.2 2 0.1 5 * Eggs/yea r

1,75 0 * 8,06 2 38,75 0 1,340 67,00 0 105,00 0 *

Unidentifie d gobie s Ba y gob y Blackey e gob y Longja w mudsucke r Hypsoblennius spp . Pacifi c herrin g Whit e croake r Pacifi c stagho msculpi n AEL * 1,045,58 8 16,63 6 * 10,24 7 24 3 * * Tota l

Entrainmen t 2. 7 x 10 8 1.5 x 10 8 1.7 x IO

7 8. 0 x IO

6 1. 7 xlO 7 4. 4 x 10 6 8. 6 xlO 6 1. 0 xlO 7 Averag e

Lifespa n (years ) 2. 5 * . 3. 6 2. 5 7 1 1 12 * Ag e a t Maturatio n (years ) 1 * 0. 5 0. 7 2 2. 5 2 * Earl y Larva e

* 0.01 3 0.00 4 * 0.00 6 0.000 4 * * Lat e Larva e

throug h Juvenil e F

V Pre-Recrui t

* < 0.53 6 0.23 3 * 0.10 7 0.13 5 * * 'Unavailabl e informatio n o r valu e that

coul dno t

b e computed . (a ) ETM value s calculate dusin g sourc e wate r volume s 275 , 21 , an d 2. 2 m 3 x IO 6

. (b ) ETM value s calculate dusin g sourc e wate r volume s 22 , 21 , an d 2. 2 m 3 x 10 6

.

E9-053. 9 6-4 4 MLP P 316(b ) Resource Assessmen tP.5 3

6. 0 Coolin g Wate r Syste m Impac t Assessmen t Tabl e 6-30 (continued) . Summar y of Estimated MLP

P Ne w Combined-cycl e Entrainmen t Effect s fo r Abundan t Fishe s an dCance r Crab s Based o

n ETM, FH, an

d AEL Model s Usin g Entrainmen

t an dSourc e Wate

r Larva l Concentration s an

d Montere y Bay , Mos s Landing Harbor , an d Elkho m Sloug h Volume s (Marc

h 1999-Februar

y 2000) . (b ) Cancer Crab s

Hairy roc k

cra b Yello w roc k

crab Brow n roc k

cra b Dungenes s crab Re d roc k cra b Slende r cra b Tota l

Entrainmen t 1. 7 x 10 6 0. 5 x 10 s 0. 8 xlO 6 0. 3 x 10 6 0. 2 x 10 s 0. 2 x 10 " FH

1,03 9 13 1 20 9 167 6 0 23 9 ETM ,] 0.01 8 * * * 0.04 4 0.02 5 ETM<»

0.16 7 • * * 0.04 4 0.07 9

Hair y roc k crab Yello w roc k

cra b Brow n roc k

cra b Dungenes s cra

b Re d roc k cra b Slende r cra b Tota l

Entrainmen t 1.7 x 10 " 0. 5 x 10 6 0. 8 x 10 * 0. 3 x IO

6 0. 2 x 10 6 0. 2 x 10 6 FH

1,03 9 13 1 20 9 167 6 0 23 9 Eg g Surviva l 1. 0 1. 0 1. 0 1.0 1. 0 1. 0 Megalopa l

Surviva l 0.00065 7 0.00081 7 0.00106 9 0.00080 2 0.00165 8 0.00139 8 Eggs/yea r

1,530,90 7 2,600,00 0 1,756,45 0 1,250,00 0 1,492,50 0 555,58 3 Averag e

Lifespa n (years ) 4. 8 4. 8 5. 5 6. 0 4. 8 3 Ag e a t Maturatio n (years ) 1. 5 1. 5 1. 5 2. 0 1.5 1 'Unavailabl e informatio n o r valu e tha

t coul d no t

b e computed . (a ) ETM

value s calculate d usin g sourc e wate r volume s 275 , 21 , an d 2. 2 m 3 x IO 6

. (b ) ETM

value s calculate d usin g sourc e wate r volume s 22 , 21 , an d 2. 2 m 3 x IO 6

.

E9-053. 9 6-4 5 MLP P 316(b ) Resource Assessmen tP.5 4

6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

## 6.1 7 Impingemen t Effect s Assessmen t Th e combined-cycl e intak e modernizatio n projec t i s expecte d t o significantl y reduc e histori c impingement

rate s b y modernizatio n o f th e existin g Unit s 1 throug h 5 intake . Th e existin g intak e structur e wil l b e modifie dt o eliminat e it s 350-foo t forebay tunnel . Base d o n intak e structur e desig n guidanc e (EPA , 1976 ) lon g tunnel s o r channel s i n front

of afacility' s intak e screen s entrap fishe s an dinvertebrate s an d shoul d b e avoide d wheneve r possible . Th e previou s (197 9 - 1980 ) MLP P impingemen t rate s reviewe d i n Sectio n 5 showe d tha t impingemen t

rate s measure dat

Unit s 1 throug h 5 intak e wer e significantl y highe r tha t at Unit s 6 an d 7 intake , particularl y i

n th e rat e o f

crab impingement . Thi s highe r impingemen t

rat e i s attributabl e i n a larg e part t o th e entrapmen t

effec t ofth e Unit s 1 throug h 5 intake' s extraordinaril y lon g forebay . It i s therefor e reasonabl e t o forecas t that wit h th e eliminatio n ofth e existin g intak e forebay (makin g th e intak e flus h t o th e shoreline ) tha t th e modernize d intake' s impingemen t rat e woul d b e equivalen t

t o th e impingement

rat e observe d a

t Unit s 6 an d 7' s shorelin e intake . Th e benefit , reductio n o f impingement

losses , ca

n b e estimate d b y usin g th e historica l impingemen t

rate s describe di n Sectio n 5 . O n thi s basis , th e effec t o f movin g th e intak e foreba y an d screen s t o th e shorelin e woul dhav e reduce d th e tota l annua l impingemen t o f fishe s a t Unit s 1 throug h 5 fro m2,875/da y t o 1,657/da y an d th e tota l annua l impingemen t o f crab s fro m 236/da y t o 139/day . In additio n t o thi s leve l o f reductio n o f

impingemen t

losse s achieve d b y movin g th e combined-cycl e intak e t o th e shorelin e location , th e modernize d combined-cycl e unit s wil l withdra w 4 4 percen t les s wate r

tha n th e existin g Unit s 1 throug h 5 pumps . Lowe r volume s o f

coolin g wate r

withdrawa l ar e expecte d t o furthe r reduc e th e potentia l for impingemen t

b y furthe r

lowerin g th e combined-cycle' s impingemen t effects . Th e relationshi p betwee n rate s o f

intak e wate r

withdrawa l an d rate s o f

impingemen t

i s not strictl y adirec t relationship , du e t o th e presenc e o r absenc e o f

debri s effect s o n impingemen t rates . A genera l relationshi p hold s tha t

i f les s wate r

i s withdraw n th e potentia l for th e impingemen t

o f organism s an ddebri s wil l b e lower . W e hav e not attempte d t o quantif

y th e expecte d benefit s o f reduce d combined-cycl e intak e flow s o n impingemen t rate s ofth e existin g facility , bu t believ e the y represen t apotentia l for

significan t

reduction s in impingemen t rate s wit h th e ne w combined

cycl e units . Ne w travelin g screen s tha t ar e planne d for

th e combined-cycl e modernize d intak e facility ma y als o contribut e t o lowe r

impingemen t

rates . Th e installatio n o f continuous-belt , inclin e screen s i s bein g investigate da s amean s t o reduc e intak e scree n maintenanc e an d improv e reliability . A biologica l benefi t

ofth e ne w scree n designs , i s tha t with fewer

structura l members , th e effectiv e scree n are ai s increase dan d through-scree n velocitie s reduce d accordingly . Th e screen s ar e installe da

t a n angle , compare d t o th e mor e commo n verticall y installe d screens . Th e angl e ofth e scree n allow s gravit y t o kee p debri s o n th e scree n surfac e a s i t clear s th e wate r

an d E9-053. 9 6-4 6 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.5 5

6. 0 Coolin g Wate r Syste m Impac t Assessmen t 

### i s lifte d t o th e spra y nozzle s an

dsluiceways . Th

e angl e o f scree n inclinatio n als o serve s to increas e th e effective screen surfac e are aan dlowe r through-screen velocitie s fro m approximately 2. 0 fp s to 0. 8 fps (se e Tabl e 2-1) . A t intak e facilitie s wher

e fish retur

n system s ar e employed , lowe

r through-screen velocitie s improv e the surviva l ofth e impinge dorganism s tha t ar e returned . Thoug

h thi s facto

r doe s not appl y to th e MLP P combined-cycl e intake , lowe r throug h scree n velocitie s shoul di

n theor y mak e i t easie r fo r small fishe s t

o navigat e i n an d ou t ofth e shorelin e intak

e structure . However , th e projecte dcombined-cycl e intak e approach velocit y of 0. 5 fps i s well belo w th e swimmin g burs t speed s of mos t ofth e stud

y area' s fishes . Lowe r through-screen velocitie s represent asmall , but

positiv e potentia

l fo r lowe r impingemen

t rate s wit h th e ne w combined-cycl e units .

E9-053. 9 6-4 7 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.5 6



## 7. 0 EVALUATIO N O F ALTERNATIV E INTAK E TECHNOLOGIE S Th e purpos e o f

thi s sectio n i s t o evaluat e alternativ e intak e technologie s for th e combined-cycl e (formerl y Unit s 1 throug h 5 ) coolin g wate r intak e structure , whic h wil l b e modifie d t o serv e th e propose dcombined-cycl e (CC ) unit s a t th e Mos s Landin g Powe r Plant . Thoug h th e entrainmen t an dimpingemen t

effect s ar e negligibl e at

thi s poin t

ofth e curren t

study , altemativ e intak e technologie s wer e evaluate dfor thei r potentia l t o furthe r

reduc e biologica l losses . Th e feasibility an d cost-effectivenes s for eac h alternativ e intak e technolog y wa s evaluate d fo r th e Mos s Landin g Powe r Plan t combined-cycl e unit s o n asite-specifi c basis . A hierarchica l evaluatio n syste mi s use dt o asses s whic h alternativ e intak e technologie s woul d reduc e biologica l losse s an d coul d b e feasibl e for

applicatio n t o th e coolin g wate r syste mofth e plant . Alternativ e intak e technologie s wer e evaluate do n th e basi s ofth e followin g four criteria : 1 . th e alternativ e technolog y i s availabl e an d prove n (i.e. , i t ha s demonstrate d operabilit y an dreliabilit y at

acoolin g wate r

intak e havin g asimila r

siz e an d environmenta l settin g t o tha t a t th e MLPP) , 2 . implementatio n ofth e alternativ e technolog y wil l resul t i n areductio n in th e los s o f aquati c organism s fro mth e presen t operatin g condition s describe d i n Sectio n 2 , 3 . implementatio n ofth e alternativ e technolog y i s feasibl e at th e MLP P site , basedo n site

specifi c consideration s o f engineering , operations , an d reliability , an d 4 . th e tota l economi c cos t ofth e alternativ e technolog y i s proportionat e t o th e environmenta l benefit s anticipated . Thes e criteri awer e applie dt o all alternativ e intak e technologie s tha t wer e considere d t o b e availabl e an dprove n for

applicatio n at

th e plan t (Criterio n 1 ) an d were , therefore , subjecte d t o a biologica l evaluatio n (Criterio n 2) . Feasibilit y analyse s (Criteri a3 an d 4 ) wer e carrie d ou t fo r alternative s tha t

woul dreduc e biologica l losses . Th e sectio n end s wit h adiscussio n of , an d judgmen t a s to , th e bes t

intak e technolog y availabl e for th e ne w combined-cycl e units . Evaluatio n o f

whethe r an intak e technolog y i s availabl e an d wil l minimiz e impact s require s site

specifi c analyses , whic h ar e presente d i n thi s section . Th e desig n an d operatio n o f th e coolin g wate r system s for

th e ne w combined-cycl e unit s ar e describe d i n Sectio n 2 , alon g wit h a discussio n ofth e physica l an dbiologica l characteristic s ofth e sourc e waterbody . S f ction s 3 throug h 5 presen t

informatio n characterizin g entrainmen t an d impingemen t

a t th e plant . Thi s backgroun dinformatio n provide s th e site-specifi c framewor k necessar y for

evaluatin g th e potentia l biologica l effectivenes s an d engineerin g feasibilit y ofeac h intak e technolog y considered .

E9-053. 9 7- 1 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.5 7

7. 0 Evaluatio n o

f Alternativ

e Intak e Technologie s 

## 7. 1 First-leve l Evaluatio n —Ar e th e Technologie s Prove n an d Available ? Certain intak

e technologie s an

dalternat e intak e location s wer

e determine dt

o b e proven an

d availabl e fo

r consideratio n fo

r th e ne w CC unit s (Tabl e 7-1) . Thes e include offshor e an d onshor e intak e location s an

dconfigurations , aonce-through coolin g water system , an

d behaviora l barrier s suc

h a s light , sound , bubbl e screens , an dvelocit y caps . Fis h diversio n systems , suc

h a s louver s an

dangle dscreens , hav e bee

n useda t coolin g water

intak e structure s (CWIS ) an

dca n b e considere dfo

r us e by th e CC

units . Physica

l barriers , such a s dru

mscreens , center-flo w screens , andvertica l travelin g screens , ar

e als o appropriat

e fo r furthe r consideration . Fis h collectio n an

dretur n systems , includin g modifiedtravelin g screen s andfish pum p system s are availabl e considerations . Although no t

commonl y useda s intak

e technology , closed-cycl e coolin g systems , suc h a s sal t water coolin g tower s an

dai r cooledcondensers , hav e bee n demonstrate di

n power plant applications .

E9-053. 9 7-2 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.5 8

7. 0 Evaluatio n o

f Alternativ

e Intak e Technologie s Tabl e 7-1 . Operationa

l Feasibilit y of Intak e Technologie s an

d Operationa

l Alternative s Considere dfo

r the ProposedMLP

P Combined-cycl e Units . Intak e Technologie s Intak e Locatio n Intak e Configuratio n

Behaviora l Barrie r

Diversio n System s

Physica l Barrie r

Fis h Collection , Removal , an d Conveyanc e System s Demonstrate d Prove n an d Availabl e Offshor e Onshor e Shorelin e Recesse d Ligh t Soun d Ai r bubbl e curtai n Velocit y ca p (applicabl e t o offshor e intak e locatio n only )

Louver s Angle dScreen s Centerflo w scree n Vertica l Travelin g scree n Barrie r ne t Gunderboo m

Modifie dtravelin g wate r screen s Gravit y sluicewa y Fis h pum p No t Demonstrate d Prove n an d Availabl e

Velocit y gradien t Electrica l barrie r Chemical s Magneti c fiel d Chain s an dcable s

Medi afilter Porou s dik e Radia l Wel l Stationar y scree n Horizonta l travelin g scree n Caisso n Dru mscreen s Cylindrical , wedge-wir e screen s

Operationa l an d Flow-reductio n Alternative s
Maintenanc e an dOperationa l Modification s Closed-cycl e coolin g Coolin g wate r

pum p flow reductio n Dredgin g Seasona l Flo w Reductio n Alternat e biofoulin g contro l

E9-053. 9 7- 3 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.5 9 

# I

ffi 

# I 

# i i 7. 0 Evaluatio n o f Alternativ

e Intak e Technologie s



# 1 I I I 1 1 1 1 I 1 1 Operationa

l an dflow-reductio n alternatives , such a s closed-cycl e cooling , seasona l energy curtailmen t resultin g i

n flo w reductions , coolin g syste mstructura

l modifications , temperatur e regulation , maintenanc e dredgin g ofth e intak e area , an dcoolin g wate

r pum p flo w reductio n ar

e als o regarde da s proven an

davailabl e technologies . Othe r alternativ e technologie s failed t o satisf y th e first evaluatio n criterion , andhenc e ar e no t considere dfurthe

r i n th e analysis . Thos e technologie s andoperationa l alternative s ar

e discusse dbriefl

y i n the followin g discussion . 

### 7. 1. 1 Behavioral

Barriers Device s suc

h a s velocit

y gradients , electri c barriers , magneti c fields, wate r je t curtains , hangin g chains , visua

l cue s andchemical s hav e been suggested , an di n som e case s evaluated , a s fish protectio n measures . However , n o practica l application s ofthes e device s hav e bee n develope d an dthey ar e no t considere davailabl e technologie s fo r applicatio n a

t CWI S (Taft , 1999) . Ofth e remainin g behaviora

l barriers , lights , soundan

dair bubbl e curtain s ar

e carrie dforwar

dt o the nex t level o f evaluation . 

### 7.1.2 Diversion

Systems Louver s hav e bee

n use deffectively a

t severa l larg e agricultura

l wate r diversion s an

d hydroelectri c installations . Onl y on e powe

r plant coolin g wate

r intak e incorporate s louvers . However , n o biologica

l evaluation s o f

thi s installatio n hav e been performed . Mos t of the louve r application s to dat

e hav e been wit

h migrator y specie s i n riverine environments . Therefore , th e abilit y o f thi s alternativ e to protec t

specie s commonly impinge da t CWI S i s largel y unknown . Further , du e to th e larg e spacing s betwee n louve r slats , louve

r system s do no t

provid e apositiv e barrier eithe r to early lif

e stage s o f

fishes o r to debri s tha

t coul dbloc k

th e condenser

tub e system andlea d to reduce doperatin g reliabilit y andincrease dmaintenance . Therefore , travelin g wate r screen s ar e require ddownstrea

mo f louver s fo

r CWI S applications . Futur e consideratio n o f louve r system s fo

r protectin g fishes a

t coolin g water

intake s ma

y b e warrante dbut

would requir

e extensiv e large-scal e engineerin g feasibilit y andbiologica

l evaluations .

Medi afilters, such a s rapi dsandfilters, porou s dikes , an dradia l wel l intakes , hav e never

been use dt o provid e powe

r plant coolin g water

fro mamarin e source . Prototyp e test s hav e bee n conducte dtha

t hav e identifie ddebri s accumulation , biofouling , andsedimentatio n a s majo r constraint s i

n th e applicatio n o f

medi afilters i

n th e marin e environment . Result s of laborator y andsmall-scal e pilo t

studie s hav e indicate dtha

t porou s dike s migh

t b e effectiv e i

n preventin g passag e ofjuvenil e andadult fishes. However , entrainabl e organism s wil l generall y b e trappe d i n the porou s mediumo

r entraine dinto th e pum

p flow . E9-053. 9 7-4 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.6 0 ffi 

## ffi m 

### ffi 

# 1
ffi 

# i 7. 0 Evaluatio n o f Alternativ

e Intak e Technologie s



# 1 1 1 1 ffi 

# 1 1 1 1 1 1 1 1 I

n th e absenc e o f

demonstrate dperformanc e capabilitie s andoperationa l reliabilit y i n aonce through powe

r plant coolin g wate

r system , medi afilters are no t considere dt

o b e a n availabl e technolog y fo

r th e ne w combined-cycl e units . T o date , large-scal e CWI S application s of wedge-wir

e screen s hav e been limite dt o tw o powe

r plants . Thes e screen s hav e been biologically effectiv e i n preventin g entrainment

an d impingemen

t o f large r fishe s andhav e no t

cause dunusua

l maintenanc e problems . Thi s technolog y ca

n b e considere dfo

r applicatio n a

t CWIS . However , ther

e are majo r concern s wit

h cloggin g potentia

l an dbiogrowth . Sinc e th e only tw o larg e CWI S t o emplo y wedge-wir

e screen s t o dat e us e 6. 4 and1 0 m

mslot openings , th e potentia

l fo r cloggin g an

dfouling tha

t would exis t wit h slot size s a s small a s 0. 5 mm , a s woul db e require dfo r protectio n o f

entrainabl e lif

e stages , i s unknown . I

n general , consideratio n o

f wedge-wir

e screen s wit

h small slo t

dimension s fo

r CWI S applicatio n shoul dinclude in situ prototyp e scal e studie s to determin e potentia l biologica l effectivenes s an

didentif y th e abilit

y t o contro l cloggin g an

dfouling i n awa y tha t doe s not impact plan t operation . Assumin g tha

t biofoulin g ca

n b e controlled , th e only environmen t i n which us e o f

cylindrica l wedge-wir

e screen s ma

y no t b e practicabl e i s on e without a n ambien t cross-current

t o carr y passiv e organism s an

dbackflushe ddebri s away . Stationar y screen s hav e ha

dlittl e applicatio n a

t CWIS . No information i s availabl e o n recen t advance s or

installation s o f

flat-panel screen s fo

r us e a s afish barrier . Excep t on small volum

e intakes , i t i s expecte dtha

t maintainin g fixed screen s i n aclea n condition , andthereb y minimizin g hea

dloss , wil l preclude us e ofthes e screens . Th e travelin g water

screen i s astandar

dfeatur e a t mos t CWIS . Th e abilit

y o f travelin g screen s t o ac t a s abarrier

t o fishes whil e not

resultin g i

n impingemen

t i s dependent

on man y site-specifi c factors , such a s th e siz e offish , locatio n ofth e screens , andpresenc e o f escap e routes . It

i s considere dadvantageou s to locat e screen s clos e to th e shorelin e a t th e point of water withdrawal , a s propose dfo

r th e ne w C C unit s CWIS . Travelin g screens , a s barrier devices , cannot

b e considere dfo

r protectio n o f

early lif e stage s o r

aquati c organism s tha

t hav e littl e or

no motility . The horizonta

l travelin g screen concep t

combine s element s o f

diversio n an dcollectio n device s an dmigh t hav e been a

n effectiv e fish protectio n systemi f engineerin g problem s coul dhave bee n overcome . Unfortunately , year s o f design , research , anddevelopmen t effort s a t tw o site s did not result i n ascreen tha

t coul doperat

e reliably , even fo

r relativel y shor

t period s oftime . Ther

e ha s bee n n o additiona

l wor k on thi s technolog y andit

i s no t considere davailabl e fo

r applicatio n a

t CWIS . Similarly , whil e rotar

y dm mscreen s ar

e ofte n mentione da s technologie s fo r protectin g fishe s a

t CWIS , n o evidenc e of

application s exists . Dm

mscreen s hav e been use da t irrigatio n and hydroelectri c facilitie s but , even i n thes e applications , th e screen s ar e limite db y th e requiremen t E9-053. 9 7- 5 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.6 1 

# 0 0

i i



# 0
n



# fi l l 

# 8 8 8 7. 0 Evaluatio n o f Alternativ e Intak e Technologie s 

### fo r maintainin g constan

t wate r elevations . Dmm s screen s ar e no t considere dt o b e biologically effective , base do

n the limiteddat

aavailabl e (Eicher , 1974) , an dar e no t expecte dto reduc e th e number s o f

organism s entraine do

r impingeda

t the plant' s coolin g water

intak e stmctures . Ther

e i s n o information availabl e t o sugges t tha t surviva l of organism s impinge don dm mscreen s wouldb e significantly differen t fro mimpingemen

t surviva l o n conventiona

l vertical travelin g screens . I n th e absenc e o f

an y predicte dbiologica

l advantages , dm

mscreen s are no t

considered to b e a n acceptabl e alternativ e intak e technolog y applicabl e t

o th e ne w combined-cycl e units . 

### 7= 2 S©c©odl=L@v@[ l EvsiDyattBo o —WBi D Th e T®c[ftm)©l!©g y Rosuil t D m Boctogiea O Bernefe ? Each technolog y andoperationa l alternativ e tha

t satisfiedth e proven an

davailabl e criterio n i

n the first-level evaluatio n (Tabl e 7-1 ) wa s furthe r investigate dt

o determin e whether

it would reduc e the entrainmen

t an dimpingemen

t losse s reporte di

n Section s 4 and5 . Relevant result s o f the evaluatio n ar

e integrate di

n thi s section . 

### 7.2.1 Closed-Cycle

Cooling

Water System A closed-cycl e coolin g wate r syste ma t MLP P coul dreduc e intak

e effect s b y reducin g the us e of seawate r fo r cooling . Thi s alternativ e woul dreplac e th e once-throug h ocea n coolin g wate

r systempropose dfo

r th e ne w CC unit s wit

h eithe r arecirculatin g coolin g water systeman d coolin g tower(s ) o r

ai r coole dcondensers . Wit h th e coolin g tower

scheme , war

mwater fro mthe stea mturbin e condenser s andother coolin g wate

r user s i n the plan t wouldflow t

o ane w coolin g tower(s ) consistin g o f air-wate r contac t surface s (slats ) an

delectri c motor-driven fans , i n the cas e o f

amechanica

l draf t tower , or contac t surface s containe di

n wha t i s essentiall y aver

y larg e chimney i

n th e cas e of anatura

l draf t tower . Th e recirculatin g wate r t o b e coole dfall s fro

mth e top throug h th e tower wher e i t contact s ahig h air

flo w drawn through th e towe

r by th e fan s or

th e draf t ofth e chimney . Coolin g occur s throug h partia l evaporatio n ofth e falling wate r (simila r to th e operatio n of a "swamp " cooler) andcontac t coolin g o f

th e wate r b y th e coole

r air . Coole dwater

collect s i n a larg e basi n beneat

h th e towe r wher e coolin g wate

r circulatio n pump s retur

n th e water

t o th e condenser s an

dother equipmen t use s t o repea t th e cycle . Recirculatin g wate

r i s los t fro mth e proces s principall y i n tw o ways : evaporatio n fromth e towe r an da"blowdown " (purge ) stream . Th e blowdow n strea

mi s intentionall y remove dto preven t th e buildup o f

dissolve dsolid s i

n the recirculatin g wate

r sinc e th e solid s d

o no t evaporate i

n the tower . A thirdmino r

los s consist s of

liqui dwate

r droplet s (drift

) entraine dwit

h th e air an d wate r 

# B E9-053. 9 7- 6 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.6 2

7. 0 Evaluatio n o

f Alternativ

e Intak e Technologie s 

### m 

### ffi g j 

### ffi 

# I 

# 1 1 i 1 1 1 1 I 1 1 1 1 I 1 1 1 vapor

leaving th e top ofth e coolin g tower . Th e evaporation , blowdown , an ddrif t losse s mus t

b e replenishe d b y addin g replacemen t ("makeup" ) wate

r t o th e system . For

aseawate r recirculatin g coolin g syste

mservin g the ne

w CC units , th e estimate docea n water require dfo

r makeu p i s abou t 4. 8 percen t ofth e proposedonce-throug h coolin g wate r intak e rat e an dconsequentl

y th e entrainmen

t of organism s couldb e reducedu p t o 95. 2 percent . I n a n air-coole dcondense

r system , exhaus t

stea mfro mth e stea mturbin e generato r

i s coole d an

d condense di

n alarg e externa

l hea t exchange r using atmospheri c air

a s th e coolin g medium . Large , electri c motor-driven fan s mov e larg e quantitie s ofai r acros s finne

dtube s (simila

r i n principl e t o a n automobil e radiator

) through whic

h th e exhaus t

stea mi s flowing . Hea

t transfe r fro mth e hot stea mt o th e ai r cool s th e stea

mcausing i

t t o condense . The heate dai

r i s exhausted to th e atmosphere . I

n thi s case , ther

e wouldb e n o seawate

r require dfo

r condenser

cooling . Air-coole dcondenser s fo

r powe r plant s ar e ver y larg e stmcture s an

dconsum e significan

t amount s of

powe r fo r operatio n ofth e fans . The y als o significantly reduc e stea mturbin e outpu

t du e to highe

r condensin g temperature s as comparedt o once-throug h o

r recirculatin g wate

r condensers . The mos t importan t impacts o f cooling towers ar

e ai r quality , ambien

t noise , an daesthetics . Du

e t o the heigh t an dlengt h of cooling towe

r structure s an

dthei r visible vapor , cooling tower s have a visua l an daestheti c impac

t o n th e surrounding area . Nois e emission s during operation must b e considered , particularly wit

h mechanica

l draf t towers . Extr

afossi l fue l i s require dt o b e burned t o compensat e fo r the averag e los s i

n generatio n a

t powe r plant s wher

e mechanica

l o r natura l draf t tower s ar e retrofitted . Thi s wouldhav e adirec t effec t o n ai r quality . 

### 7.2.2 Intake Location Alternativ e intak

e location s fo

r th e new combined-cycl e unit s a t th e MLP P includ e submerge d offshor e an d shorelin e intak

e locations . The propose dshorelin e intak e locatio n andconfiguratio n fo r th e ne w CC unit s i s th e bas e cas e agains t which eac h alternativ e i s compared . 7.2.2. 1 Offshor e Intak e Locatio n 

### Th e efficacy ofa n offshor

e intak e i n reducin g entrainmen

t depends , to alarg e degree , o n th e vertica l stratificatio n o f

entrainabl e organism s i

n th e wate r colum n a t th e point o f water withdrawal . I

n suc h asystem , areductio n i

n entrainmen

t i s achieve db y locatin g th e submerge d intak e a t adept h wher e th e concentratio n o f

entrainabl e organism s i s les s tha n a t other depths . Althoug h th e availabl e dataar e limited , entrainabl e organism s ar e expecte dt o b e distribute d i n approximately equa

l concentration s throughout th e wate r colum n a s aresul t

o f stron g tida

l and wind.mixin g andth e shallo w depth s i n the immediat

e are aofth e MLP

P (Subsectio n 2.2.2) . E9-053. 9 7- 7 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.6 3 ffi 

# I ffi 

## tt St 

# 1

I B 

# 1 i 1 1 I I 1 1 1 1 1 1 7. 0 Evaluatio n o f Alternativ

e Intak e Technologie s 

### Wate r depth s ar e typically les s tha

n 3 0 ft ( 9 m) withi n 2,00 0 ft

(60 0 m ) ofth e existin g intak

e locations . Man

y specie s tha

t hav e planktoni c larva

e which ar e susceptibl e t

o entrainment , such a s flatfishes , rockfishes , whit

e croaker , smelts , andnorther n anchovy , spawn in th e nearshor e water s o f Monterey Ba

y an dpotentiall y coul db e mor

e susceptibl e to entrainment a t a n offshor e intak e tha n unde r th e present

configuration . Becaus e of

the larg e tida

l exchang e between Mos s Landin g Harbor-Elkhor

n Slough andMonterey Bay , planktoni c organism s spawne di n th e harbor-slough , such a s gobie s andPacifi c herring , wouldb e susceptibl e to entrainmen t a t a n offshor e coolin g wate

r intak e site di n th e are aadjacen

t t o th e Mos s Landin g Harbor entranc e channel . Furthermore , ver

y littl e i f an y vertica l stratificatio n i

n th e concentration s of

planktoni c egg s an d fish larva

e i s expecte dto occu

r i n thes e shallo w areas , which ar e subjec t t o mixin g an

d turbulenc e fro

mtida l currents , waves , an

dwind . Becaus e th e water s nea r th e plant ar e well

mixe dfro msurfac e t

o bottomb y virtu e ofth e larg e tida l pris mandth e turbulenc e a t th e entranc e t o Mos s Landin g Harbor

a t bot h floodan deb b tide stages , a

n offshor e intak e stmctur e would not b e expecte dt

o reduc e th e number s of

organism s entrained . For reducin g th e numbe

r o f impinge dorganisms , the effectivenes s ofasubmerge doffshor e intak e depend s o n locatin g th e intak e i n a n are awher

e suc h impingeabl e organism s ar e not abundant . Man

y ofth e dominan

t group s o f fishe s an dinvertebrate s (e.g. , flounde r an dsole , rockfishes , whit

e croaker , surfperches , crabs , shrimp ) ar e typicall y foun

di n associatio n wit

h th e offshor e bottomhabita

t i n th e vicinit

y ofth e site , an

dman y ofth e typicall y pelagi c fish species , suc h as smelts , norther

n anchovy , an

dPacifi c herring , ar

e commonly foun

di n larg e school s which mov e throug h th e wate r column , ofte

n concentratin g nea

r th e botto msubstrate s durin g th e daytim e (EA , unpublished) . I

n addition , submerge doffshor e intake s generall y hav e highe r approac h velocitie s tha

n onshor e system s an

dus e conduit s withi n which fishes ca n becom e entrapped , resultin g in a

n increas e i

n th e numbe

r o f organism s impinged . Furthermore , ther e i s a distinc t possibilit y tha t th e physica

l presenc e andnatur

e of a n offshor e intak e wouldattrac t

man y ofth e fishe s an

dinvertebrate s inhabitin g Monterey Ba y (particularl y surfperch , rockfishes , an d crabs ) t o th e intak e location , ands o increas e th e probabilit y of entrapment

an dsubsequen

t impingement . Thus , us e of asubmerge doffshor

e intak e syste mwoul dprobabl y result

i n rate s of impingemen

t higher tha n thos e observe da

t th e existin g intakes . I n summary , a

n offshor e intak e appear s to offe

r littl e or no potentia

l fo r reducin g th e losse s o f fishes an dinvertebrate s entraine dor impinge da

t the ne w combined-cycl e unit s intake . The susceptibilit

y of planktoni c organism s to entrainmen t wouldno t

b e reduce dby relocatin g th e intak e offshore , wher

e tida l current s andturbulenc e ar e expecte dt o contribut

e to ahomogeneou s vertica l distributio n o f

planktoni c organisms . The offshor e intak e woul dals o contribute to th e entrapment

of fishe s an dinvertebrates , man

y of which ma y b e behaviorall y attracte dt o th e offshor e intake . I

n addition , relocatio n ofth e intak e offshor e wouldcreate anavigationa l hazar d a t th e entranc e channe l to Mos s Landin g Harbor , an da s such , migh

t not b e permitte db y the E9-053. 9 7- 8 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.6 4 

# I I I I B 7. 0 Evaluatio n o f Alternativ

e Intak e Technologie s



# i i i i i I i i i i I i i responsibl e regulator y agencies . I n th e absenc e o f an y evidenc e of aclea r

potentia l for

reducin g entrainmen t

an dimpingemen t

losses , a n offshor e intak e locatio n i s no t considere d t o b e an acceptabl e alternativ e for th e ne w C C units . 7.2.2. 2 Alternativ e Onshor e Locatio n Th e genera l similarit y ofth e shore-zon e habita t alon g th e shorelin e o f

Mos s Landin g Harbo r

o r Elkho mSloug h suggest s tha t th e potentia l for

entrainmen t

an d impingemen t

woul d no t

b e substantiall y differen t

a t an y othe r

availabl e shorelin e locations . Th e patter n o f tida l current s an d mixin g i n th e are aresultin g fromth e larg e volum e ofth e tida l pris mrelativ e t o th e volum e ofth e harbor-sloug h (Subsectio n 2.2. 0 support s th e conclusio n that th e concentration s o f

organism s ar e simila r throughou t

th e local shor e zone) . Durin g 197 1 an d1972 , PG& E (1973 ) conducte d afishery surve y a t fou r samplin g station s i n Mos s Landin g Harbo r

an dElkho mSlough . Samplin g was don e quarterl y wit h otte r trawl s an d both sinkin g an dfloatin g gil l nets . A tota l o f 71 3 fishe s was collecte d fro mth e harbor-sloug h syste mdurin g thre e samplin g periods . Statistica l analyse s wer e performe d t o determin e whethe r difference s i n catche s o f

fishe s amon g th e variou s samplin g station s i n th e harbo r an d sloug h wer e statisticall y significant . Ther e wer e n o statisticall y significan t difference s i n th e number s o f fishes collected , th e number s o f species , th e averag e weights , o r th e averag e length s o f

fishe s collecte da t

th e variou s samplin g station s throughou t Mos s Landin g Harbo r

an d Elkho mSlough . Th e result s o f

thi s serie s o f

fishery collection s provid e n o evidenc e tha t alternativ e shorelin e intak e location s ar e availabl e i n Mos s Landin g Harbo r o r Elkho mSloug h tha t

woul d resul t

i n reduce drate s o f

impingement . Studie s b y Nybakken , Cailliet , an dBroenko w (1977 ) offis h population s i n th e Mos s Landin g are asugges t

tha t fish abundanc e i s generall y highe r nea r th e Highwa y I Bridg e tha n i n th e are a adjacen t t o th e harbo r

entranc e i n Montere y Bay . Fis h abundanc e wa s intermediat e at samplin g station s i n Elkho mSlough . However , sinc e n o sample s wer e collecte d i n Mos s Landin g Harbo r nea r th e existin g coolin g wate r intak e locations , th e result s ofthes e studie s canno t b e use d for comparison s usefu l i n evaluatin g potentia l alternativ e intak e location s tha t migh t contribut e t o a reductio n i n impingemen t losses . Dat acollecte do n th e concentration s offis h egg s an d larva e an d macroinvertebrate s durin g plankto n survey s at

si x station s locate d throughou t Mos s Landin g Harbo r

an d Elkho mSloug h (EA , 1982 ) provid e n o evidenc e tha t alternativ e shorelin e intak e location s ar e availabl e i n th e harbor-sloug h syste mtha t woul dreduc e entrainmen t losses . Averag e dail y concentration s o f fish egg s wer e no t

significantl y differen t

amon g station s sample d i n Mos s Landin g Harbor , althoug h concentration s ther e wer e consistentl y highe r tha n thos e fro mth e uppe r sloug h station s a t th e Dairie s an dKirb y Park . Althoug h th e concentration s o f fish larva e wer e lowes t

a t th e E9-053. 9 7- 9 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.6 5 

# I

ffi



### ffi 

## fi 

# I m 

# 1

! 

# I 1 1 

# 1 I 1 1 7. 0 Evaluatio n o f Alternativ e Intak e Technologie s



### samplin g statio n directly adjacen t t o th e existin g coolin g wate r intakes , difference s i

n concentration s wer

e no t significan t among station s i

n the harbor

an dlowe r slough . Highes t larva l fish concentration s occurre da t station s i n th e uppe r slough a t th e Dairie s andKirb y Park . N o significan

t difference s i

n th e number s o f

larva l fish tax awer

e detecte damon g al l station s surveye d i n the harbor

an dslough . Ther

e wer e no significan

t difference s betwee n th e averag e daily concentration s o f

macroinvertebrate s collecte da t th e Dairie s i

n uppe r Elkho mSlough , a

t th e statio n nea

r th e Highwa

y I Bridge , a

t th e Mos s Landing Harbor

entranc e channel , o r

adjacen t t o the existin g coolin g wate r intak e locations . Macroinvertebrat e concentration s wer

e lowes t a t Kirb y Par k i n th e uppe r sloug h an da t the statio n adjacen

t to the existin g intak

e location s i

n Mos s Landin g Harbor . The result s ofthes e survey s indicat e tha t planktoni c organism s susceptibl e t o entrainment

ar e distribute dby tida

l current s an

db y habita t preferenc e throughou t

Mos s Landing Harbor andElkho mSlough . N o alternativ e shorelin e intak e locatio n ha s been identifie dtha t would resul t

i n areductio n i

n entrainmen

t losses . 

### 7.2.3 Behavioral

Barriers Strob e light s hav e effectivel y repelle dsevera

l differen t fish specie s i

n laborator

y an dfield experiments . Recen

t studie s hav e demonstrate dtha t variou s lacustrine , riverine , an danadromou s specie s wil l avoi dstrob e light . Conversely , som e studie s hav e indicate dtha t certai n specie s fro

m simila r environment s o r

wit h simila r lif e histor y strategie s or

phylogen y will no t respon d t o strob e light s i

n alaborator

y settin g or

unde r fieldcondition s (Brown , 1999) . Air bubbl e curtain s generally hav e bee n ineffectiv e i

n blockin g or

divertin g fishes i

n avariet y o f field applications . Ai

r bubbl e curtain s hav e bee

n evaluate da

t numbe r o f site s on th e Grea

t Lake s wit h avariet y o f species . All air

bubbl e curtain s a

t thes e site s hav e been remove dfromservice . Th e focu s o f

recen t fish protectio n studie s involvin g underwate r soundtechnologie s ha s bee n o n th e us e o f new type s o f

low

- andhigh-frequenc y acousti c system s tha t hav e no t previousl y been availabl e fo

r commercia

l use . High-frequenc y (120kHz ) soundha s show n to effectively an d repeate d repe l member s ofth e genu s Alosa (America n shad , alewife , andbluebac k herrin g a t site s throughout

th e U . S . (Ploskey et

al. , 1995 ; Dunning , 1995 ; Con Ed. , 1994) . Othe r studie s hav e no t shown soundto b e consistently effective i n repellin g specie s such a s largemout h bass , smallmout h bass , yello w perch , walleye , rainbo w trou t (EPRI , 1998) , gizzar

dshad , Atlanti c herring , and ba

y anchovy (Con Ed. , 1994) . Give n th e species-specifi c response s t o differen t frequencie s tha

t hav e been evaluated , an

dth e variabl e result s tha

t ofte n hav e bee n produced , additiona l researc h i s warrante da

t site s wher

e ther e i s n o or limite ddatat

o indicate tha

t th e specie s o f concer n ma y respon dt

o sound . I n th e nea r field, fish respons e to "sound " i s probably mor e relate dto particl e motio n tha n acousti c pressure . Particl e motion i s ver y pronounce di

n th e nea r field of asoun dsourc e an

d i s E9-053. 9 7-1 0 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.6 6

7. 0 Evaluatio n o

f Alternativ

e Intak e Technologie s 

### majo r componen

t o f wha t fishe s mos t

likely sens e fro

minfrasoun

d(frequencie s les s tha

n 5 0 Hz) . I n th e first practica l applicatio n o f

infrasoundfo

r repellin g fishes , Knudsen e t al . (1992 , 1994) , foun dapiston-typ e particl e motio n generator operatin g a

t 1 0 H z to b e effective i

n repellin g Atlanti c salmon smolt s in atan k and in asmall diversio n channel . Followin g th e succes s o f Knudse n et al . (1992 , 1994) , there wa s agenera l belie f i n th e scientifi c communit

y tha t infrasoundcoul drepresent

a n effectiv e fish repellent

sinc e ther e wa s aphysiologica

l basi s fo r understandin g th e respons e of fishes t o particl e motion . Th

e potentia l fo r currently availabl e infrasoundsource s t

o effectivel

y repel fishe s ha s bee

n brough t into questio n b

y th e result s of mor e recen t studies . Give

n thes e results , i

t appear s tha

t infrasoun dsource s needt

o b e furthe

r develope dan

devaluate dbefor

e they ca n b e considere da

n availabl e technolog y fo

r applicatio n a

t CWIS . Respons e to mercur

y ligh t ha s bee n shown t o b e specie s specific ; som

e fish specie s ar

e attracted , other s repelled , andother s hav e demonstrate dno obviou s response . Therefore , carefu l consideratio n mus t

b e give n fo r an y applicatio n of

mercur y light s to avoi dincreasin g impingemen

t of som e species . Electri c barrier s hav e bee

n shown t o effectivel

y preven t the upstrea

mpassag e of

fishes . However , anumbe

r of attempt s t o diver t or deter the downstrea

mmovemen

t of fishes hav e me

t wit h limite dsucces s (Bengeyfield , 1990 ; Kynar dan dO'Leary , 1990) . Consequently , pas t evaluation s hav e no t

lea dto permanen

t applications . Electri c barrier s hav e bee n use dwit h limite dsucces s i

n freshwater , but

becaus e of

lo w electrica

l resistance , no applicatio n o f electri c fish barrier s ha s been made i n salt or brackis h waters . Give

n their pas t ineffectivenes s an

d hazar dpotential , electri c screen s ar e no t considere daviabl e technolog y fo r applicatio n a

t CWIS . A velocit y ca p wa s no t considered , sinc e it s applicabilit y i s restricte dt

o offshor e intakes , which wer e rejecte dfo

r possibl e us e a

t th e plant (Subsectio n 7.2.2.1) . I n general , behaviora

l barrier s hav e no t

proven consistently effectiv e i n reducin g th e number s o f fishe s impinge da

t CWIS . I n addition , such barrier s ar e no t expecte dto reduc e th e number s of entraine d organism s or

th e impingemen

t rate s o f macroinvertebrates . Behaviora l barrier s ar

e no t considere d t

o represent

a n effectiv e alternativ e fo

r reducin g entrainmen

t o r impingemen

t a t the plant . 

### 7.2.4 Physical

Barriers Th e applicabilit

y o f physica l barrier screens , such a s vertica

l travelin g screens , centerflo w screens , barrie

r nets , andth e relativel y new Gunderboo mfo r reducin g biologica

l losse s associate d wit

h entrainment

an dimpingemen

t a t the ne w combined-cycl e unit s i s evaluate d i n th e followin g discussion . E9-053. 9 7-1 1 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.6 7



### m 

# 1 

# I 1 1 I 

# 1 i i i 7. 0 Evaluatio n o f Alternativ

e Intak e Technologie s



# i Travelin g screen s o f variou s type s (e.g. , through-flow , dual-flow , an d center-flo w wit h coars e an dfine mesh ) ar e standar dfeature s at CWIS . Withou t

th e additio n o f

variou s fish handlin g desig n (e.g. , fish liftin g buckets ) an d operatin g feature s (e.g. , continuou s scree n operation) , travelin g screen s generall y resul t i n hig h mortalit y t o al l but th e hardies t

specie s tha t

becom e impinge do n them . The y hav e n o capacit y for protectin g entrainabl e size d organisms . I f thes e screen s ar e place drelativel y flus h wit h th e fac e ofth e CWIS , a s propose d fo r th e C C units , travelin g screen s ca n b e considere d t o offe r protectio n t o juvenil e an d adul t fishes tha t

hav e th e swimmin g capabilit y t o avoi dimpingement . Unde r th e prope r

hydrauli c condition s (primaril y lo w velocity ) an d withou t heav y debri s loading , barrie r net s hav e bee n effectiv e i n blockin g fish passag e int o wate r intakes . Severa l recen t application s i n th e midwes t Unite dState s hav e bee n presente d (Michau d an d Taft , 1999) . A t th e Ludingto n Pumpe dStorag e Plan t o n Lak e Michigan , a2.5-mil e lon g barrie r net , se t i n ope n wate r aroun dth e intak e jetties , ha s bee n successfu l in reducin g entrainmen t o f al l fish specie s that occu r i n th e vicinit y ofth e intak e (Reide r e t al. , 1997) . Th e ne t

wa s first deploye d i n 1989 . Modification s t o th e desig n in subsequen t year s le d t o ane t

effectivenes s for

targe t specie s (fiv e salmoni dspecies , yello w perch , rainbo w smelt , alewife , an d chub ) o f ove r 8 0 percen t

sinc e 1991 , with a n effectivenes s o f

9 6 percen t

i n 199 5 an d 1996 . I n 199 3 an d1994 , Orang e an dRocklan d Utilities , Inc . sponsore d astud y of a3.0-mm , fin e mes h ne t at it s Bowlin e Poin t

Generatin g Statio n o n th e Hudso n Rive r (LMS , 1996) . I n 1993 , fine suspende dsil t

cause dth e ne t

t o clo g an d sink . I n 1994 , sprayin g wa s not effectiv e i n cleanin g th e ne t whe n it becam e foule db y th e alga e Ectocarpus spp . Excessiv e foulin g cause d tw o ofth e suppor t pile s t o snap , endin g th e evaluatio n (LMS , 1996) . I n bot h years , abundanc e ofth e targe t ichthyoplankto n species , ba y anchovy , wa s to o lo w t o determin e th e biologica l effectivenes s o f th e net . O n th e basi s o f

studie s t o date , th e researcher s conclud e tha t afine mes h ne t

ma y b e a potentiall y effectiv e metho dfor preventin g entrainmen t

at Bowlin e Point . However , pendin g furthe r evaluation , thi s concep t i s considere d t o b e experimental . I n conclusion , barrie r

net s ca n b e considere d aviabl e optio n fo r protectin g fishes provide d tha t relativel y lo w velocitie s (generall y les s tha n 1 ft/sec) ca n b e achieve d an d debri s loadin g i s light . A thoroug h evaluatio n o f site-specifi c environmenta l an d operationa l condition s i s generall y recommended . Th e applicatio n o f barrie r net s a t MLP P i s no t

considere d practicabl e give n th e potentia l debri s loadin g tha t exists . Th e Gunderboo mconsist s o f polyeste r fiber strand s whic h ar e presse d int o awater-permeabl e fabri c mat . Beginnin g i n 1995 , Orang e & Rocklan d Utilities , Inc . ha s sponsore d a n evaluatio n o f th e Gunderboo mt o determin e it s abilit y t o minimiz e ichthyoplankto n entrainmen t a t th e Lovet t Generatin g Statio n o n th e Hudso n Rive r (LM S 1996b , 1997 , an d 1998 ; ASA , 1999) . Despit e difficultie s i n keepin g th e boo mdeploye d an d providin g adequat e cleanin g i n 1995-199 7 studies , E9-053. 9 7-1 2 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.6 8 

# 1
n 

# I 

# I 1 I 

# 1 i § 

# i t i 7. 0 Evaluatio n o f Alternativ

e Intak e Technologie s



# I result s of

studie s i n 199 8 sho w alarg e reductio n in entrainmen t an di t appear s tha

t deploymen

t an dcleanin g problem s ma

y hav e bee n resolve dfo

r thi s site . A

t thi s time , th e Gunderboom syste mi s still considere dt

o b e experimenta

l but it s successfu

l us e a t Lovet t ma y chang e tha

t statu s withi n severa

l years . 

### 7.2.5 Fish Collection, Removal, and Conveyance

Systems Severa l modification s to conventiona l vertica l travelin g screen s hav e been considere di n recent year s i n a n attemp t t o increas e thei

r biologica l effectiveness . Som

e informatio n i s availabl e on th e effectivenes s of

variou s scree

n rotatio n frequencie s fro

mstudie s conducte da

t th e MLP P (se e PG&E , 1983 ; Sectio n 4.2) . Information i s als o availabl e fo r impingemen

t surviva l of chinook salmon fro mthe Columbi aRive

r (Pag e e t al. , 1976 , 1978 ) an

do f stripe dbas s fro

mth e Hudson Rive r (EA , 1979 ; Texa s Instruments , Inc. , 1977) . Dat afro mthes e an

dother studie s ar e used i n a genera l wa y t o provide additiona

l information usefu

l i n examinin g th e potentia

l effectivenes s of modified vertica

l screen s a t th e ne w combined-cycl e units . Th e effectivenes s o f

screen modification s fo

r reducin g impingemen

t losse s i s discusse di

n Subsection s 7.2.5. 1 throug h 7.2.5.4 . I n addition , consideratio n ha s recently been give n t o the potentia

l effectivenes s of ascree

n mes h smalle r tha n the standar

d3/ 8 in . (9. 5 mm

) but large r tha n 0.04-in . (1.0-mm) fine-mesh scree n materia l fo r reducin g th e combine dlosse s o f entrainmen

t an dimpingement . Modification s to th e desig n an doperatio n o f

vertica l travelin g screens , such a s th e us e o f continuou s screen rotation , low-pressur e spra y washes , an

dfish liftin g buckets , ar

e alternative s tha t have bee n use dt o increas e the biologica

l effectivenes s of

conventiona

l vertica l travelin g screens . I n man y cases , continuou s screen rotatio n ha s resulte din substantia l increase s i

n fish an dinvertebrat

e survival . Increasin g screen rotatio n frequency a t th e MLP P Unit s 6 ahd 7 intak

e contribute dt

o asubstantia

l increas e i

n impingemen

t surviva l fo r bot h surfperch androckfishe s (se e PG&E , 1983 ; Tabl e 4-7) . Howeve r together thes e specie s constitute donly 1 5 percent ofth e fishes impinge da

t the Mos s Landin g Powe

r Plant . The us e ofthes e modification s woul d hav e n o benefi t without afish retur

n system . However , thes e studie s als o sugges t tha t impingemen

t surviva l o f specie s such a s norther

n anchovy , Pacifi c herring , smelt , andsilversides , which togethe r constitute dapproximately 7 5 percent ofth e impingedfishes , wil l probabl y no t b e improvedsubstantially by increase dscreen rotatio n frequency. Limite dinformatio n i s availabl e t o asses s th e potentia

l o f thi s modificatio n fo

r improvin g impingemen

t surviva l fo r th e specie s offis h impinge di n greates t abundanc e a

t th e Mos s Landin g Powe r Plan t (Sectio n 5) . Among these , specie s such a s plainfin midshipman , gobies , an d crab s appeare d to hav e high survival , but fragil e specie s such a s norther n anchovy , Pacifi c herring , smelt , an dsilverside s ha

dlow surviva

l on th e existin g intak

e screens . Althoug h availabl e data E9-053. 9 7-1 3 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0

# I

• s 

# 1 I I I I I I 

# I I 

# I I 

# I 1 1 1 I I I 7. 0 Evaluatio n o f Alternativ

e Intak e Technologie s



### ar e incomplete , i

t i s expecte dtha

t surviva l of fragile specie s wouldb e increase db y the additio n offis h buckets , low-pressur e spraywashes , an

dcontinuou s rotatio n o f

screenin g surfaces . I

n particular , impingemen

t surviva l of surfperc h an drockfishe s i s expecte dto increase . 7.2.5. 1 Fine-Mes h Screen s 

### I n additio n t

o the fish handlin g provision s notedabove , travelin g screen s hav e been furthe r modified t o incorporat

e screen mesh wit

h opening s a s smal

l a s 0. 5 m mt o collec t fish egg s an

d larvae andretur

n the mto th e sourc e wate

r body . For

man y specie s andearl y lif

e stages , mes h size s o f 0. 5 t o 1. 0 m mar e require dfo

r effective screening . Variou s type s o f travelin g screens , suc h a s through-flow , dual-flow , an dcenter-flo w screens , ca

n b e fittedwit

h fine mesh scree

n material . The absenc e ofdat ao

n th e impingemen

t surviva l ofth e fish egg s andlarvae present in th e vicinit y ofth e MLP

P an dthe uncertaintie s regardin g operationa l reliabilit y o f fine-mes h screen s i n amarin e environmen

t simila r t o tha t o f Mos s Landin g Harbor-Elkhor n Slough preclude th e conclusio n tha

t fine-mesh wouldb e abiologically effective an doperationall y acceptabl e alternativ e intak

e technolog y fo

r us e a t the ne w CC units . 7.2.5. 2 Fis h Retur n Conveyanc e System s 

### Ther e ar e tw o basi c type s of

conveyanc e fo

r th e retur n of impinge dorganism s anddebri s t o the waterbody , one usin g atras h pum p t o transpor t materia l awa y fro mth e intak

e andone usin g gravit y flow . Th e pump-augmente dretur n ha s th e advantag e o f

minimizin g recirculatio n and re impingemen

t o f debri s andorganism s o

n intak e screen s due to relativel y larg e transpor t distanc e capability , but

ofte n result s i n mechanica

l abrasio n andhigh mortalit y o f organisms . Th e gravit

y sluicewa y retur n systemreduce s mechanica l abrasion , but

ma y caus e significant

reimpingemen

t becaus e of

relativel y limite dtranspor

t distances . I

t i s conclude dtha

t no furthe r consideratio n shoul db e given t

o afish pum

p retur n syste mfo r divertin g fishes fromnew C C unit s intak e becaus e ofth e uncertaintie s associate dwit h th e effectivenes s o f

such asystemi

n successfully divertin g th e fish specie s foun da t th e sit e an dreturnin g the

maliv e t o Mos s Landin g Harbor . Fishe s tha t wer e returne daliv e to th e Harbor wouldb e susceptibl e t o diseas e andpredatio n a t th e fish retur n discharg e point

du e th e stres s o f

passag e throug h th e pumpe dfish retur n system . Previou s studie s hav e conclude dtha t th e potentia

l magnitude of

reductio n i

n impingemen

t losse s attributabl e to agravit

y fish conveyanc e syste

mi s uncertai n (PGandE , 1983) . However , th e combinatio n o f

amodificatio n t

o th e screen s andtheir

operatio n an

dth e installatio n o f

a modifie d screenwas h gravit y sluicewa y retur n syste mfo r th e propose dC C unit s ma y hav e potentia l fo r improvin g impingemen

t surviva l an dwill b e considere di

n th e i n th e next ste p ofth e analysis . Becaus e ofth e uncertaintie s associate dwit h determinin g th e biologica l effectivenes s E9-053. 9 7-1 4 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.7 0 

# I

ffi 

# I I I I 1 1 1 I 7. 0 Evaluatio n o f Alternativ e Intak e Technologie s



# n n an dvariou s engineerin g desig n an doperationa l considerations , atestin g progra mwoul d b e

require dprio r

t o implementin g amodifie d scree n syste ma t th e ne w C C unit s intake . 7.2.5. 3 Summar

y Modification s o f

vertica l travelin g screen s tha t includ e fish buckets , alow-pressur e was h system , provision s for

continuou s rotation , an d afish retu msyste mrepresen t an alternativ e technolog y wit h th e potentia l for

reducin g impingemen t

losse s o f severa l ofth e specie s offis h an d invertebrate s impinge da

t th e propose d ne w C C unit s intak e stmcture . I n th e absenc e of a demonstrate dpotentia l for long-ter msurviva l for

impinge d ichthyoplankton , suc h a s norther n anchovy , Pacifi c herring , surfperch , rockfishes , whit e croake r an d flatfishes , fine-mesh screen s ar e no t considere dt o represen t

a n acceptabl e alternativ e intak e technolog y for us e in reducin g th e combine dlosse s resultin g fromentrainmen t an d impingement

a t th e modifie d intake . Insufficien t

dat apreclud e adetaile dcompariso n ofth e potential surviva l offis h egg s an d larval fishe s impinge do n modifie dvertica l travelin g screen s (fine-mes h scree n material , fish buckets , low-pressur e spraywash , continuou s rotation ) an d centerflo w screen s (fine-mes h scree n material , continuou s rotation) . T o date , n o studie s hav e bee n conducte d o f long-ter msurviva l o f

fishe s impinge do n centerflo w screen s operate d i n apowe r plan t coolin g wate r

intake , an d i t

i s unlikel y tha t surviva l woul db e an y highe r tha n for vertica l travelin g screens . Preliminar y tes t ofth e Gunderboo mbarrie r

ne t (Sectio n 7.2.4 ) indicat e that thi s technolog y i s bot h reliabl e an d effectiv e a

t eliminatin g impingemen t an d dramaticall y reducin g entrainmen t effects . Installatio n an d operatio n of abarrie r scree n i s feasibl e fo

r th e MLP P C C units . 

### 7.2.6 Intake Maintenance

And Operational

Modifications Maintenanc e activitie s an doperationa l modification s whic h ma y reduc e entrainmen t an d impingemen t

losse s includ e maintenanc e dredgin g i n front o f th e coolin g wate r

intake , reduction s i n circulatin g wate r pum p volume , seasona l curtailmen t o f coolin g syste moperation , us e o f alternativ e biofoulin g schemes , stmctura l modification s ofth e coolin g system , an d through-plan t

temperatur e regulation . 7.2.6. 1 Maintenanc e Dredgin g Sedimen t accumulatio n withi n acoolin g wate r intak e stmctur e ma y reduc e th e ope n are aofth e intake , resultin g i n increase dwate r velocities . Increase d velocitie s approachin g th e intak e stmctur e will , i n man y cases , resul t i n increase d rate s o f

impingement . Dept h measurement s mad e i n th e intak e stmctur e ofth e Mos s Landin g Powe r Plan t (PG&E , unpublished ) indicate d tha t sedimen t ha daccumulate dtha t

woul d reduc e th e availabl e cross-sectiona l are aofth e intak e (Subsectio n 2.1.3.2) . Sediment accumulatio n i n retire d Unit s 1 throug h 5 intak e stmctur e ha d reduce dth e cross-section s ofth e forebay s b y a n averag e o f

3 0 percent , rangin g from1 0 percen t E9-053. 9 7-1 5 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.7 1 

# 1

m m 

# 1 1 1 1

m m 

# I 7. 0 Evaluatio n o f Alternativ

e Intak e Technologie s



### of Ba y 3 t o 5 2 percen

t of Ba y 1 . Bay s 1 an

d6 ha dth e lowes t

mea n intak e velocity , an

d th e velocit y a t Ba y I wa s lowe

r tha n expecte dfro

mthe degre e o f

blockage . Thes e anomalie s wer e attribute d t

o th e previou s hydrauli c characteristic s ofth e Unit s 1 throug h 5 intak e stmctur e an d the considerabl e distanc e t

o th e circulatin g wate

r pumps . Sedimen

t accumulatio n i

n the Unit s 6 an d7 intak e wa s considerably les s tha n tha t i n th e Unit s 1 throug h 5 intake . Accumulate d sedimen t ha dreduce dth e cross-section s ofth e Unit s 6 an d7 forebay s b

y a n averag e of

1 3 percent , rangin g fro

m1 0 percent

a t Ba y 7- 3 t o 1 8 percen

t a t Ba y 6-1 . The reductio n i

n th e numbe r of organism s impinge dtha

t woul dresult

fro mremoving accumulate dsedimen t an d reducin g intak

e velocitie s canno t

b e estimate do

n the basi s o f

availabl e data . Ther

e i s littl e doubt , however , tha

t maintenanc e dredgin g ofth e plant intake s woul dreduc e approach velocitie s an dpotentially reduc e th e numbe r o f impinge dorganisms . A disadvantag e of dredgin g i s tha

t th e re-suspensio n o f

sediment s ha s apotentia

l negativ e impact

o n nearb y benthi c invertebrates , particularl y filter

feeders . Consequently , whil e dredgin g th e intak e migh t reduc e impingemen

t losses , areductio n i

n populatio n concentration s of som e benthi c invertebrate s wouldb e expected durin g an dshortly afte

r th e dredging . 7.2.6. 2 Circulatin g Wate rPum p Volum e Reductio n 

### A reductio n i

n th e numbe

r of circulatin g water

pump s i n operatio n and/or

installatio n o f

variable

speedcirculatin g water

pump s represent s a

n alternativ e operationa

l strategie s fo

r reducin g coolin g wate

r volume s andintak

e approach velocities , an

dhenc e reducin g the numbe r of organism s entraine dandpossibly thos e impinged . Change s i n condenser

back-pressur

e resultin g i n reduce dturbin e cycl e therma l efficiency , alon g wit

h increase dtemperatur

e differential s through th e condense

r system(delta-T) , are to b e expecte dwhe n coolin g wate

r flo w rate s ar e reduce ddurin g generation . Although areductio n i n coolin g wate

r volume i s expecte dto result i n adecreas e i

n th e numbe

r of entraine dorganisms , th e associate dincreas e i n delta- T would increas e th e discharg e temperatur e andtherma

l plum e size . Reducin g th e operatio n ofth e circulatin g water pump s durin g period s when generatio n i s lo w o r i s no t occurrin g woul dreduc e th e number s o f organism s entraine dandpossibly thos e impinged . Becaus e ofth e entrainment mortalit y resultin g fro

mpredatio n b y biofoulin g organism s tha t coloniz e th e coolin g wate

r systemconduit s a

t th e plant , entrainmen

t losse s ar e expecte dt

o b e reduce di n approximately th e sam

e proportio n a s th e reductio n i n coolin g water

flo w rates . Examinatio n o f

monthly capacit

y factor s (se e PG&E , 1983 ; Table s 2- 2 and2-5 ) an dmonthl y coolin g wate

r volume s (se e PG&E , 1983 , Table s 2- 3 an d2-6 ) indicate s tha

t circulatin g wate

r pum p operatio n typicall y exceed s generation . Although the reductio n i n entrainmen

t losse s tha t coul db e achieve dthroug h areductio n i n circulatin g wate

r pum p operatio n ha s no t

bee n precisely quantified , it

i s conclude dtha

t thi s alternativ e operationa

l mod e offers th e potentia

l fo r reducin g entrainmen

t losses . E9-053. 9 7-1 6 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.7 2

7. 0 Evaluatio n o

f Altemativ

e Intak e Technologie s 

### The numbe

r o f fishe s impingedi s expecte dt o b e reduce db y reducin g circulatin g wate r pum p operation . However , no dataar e availabl e fro

mthe 1979-198 0 impingemen t stud y (Sectio n 5 ) t

o quantif y th e magnitude o f

reductio n i

n fish impingemen

t tha t wouldresult

fro mvariou s circulatin g wate

r pum p operationa

l modes . Additiona

l studie s wouldb e require dt o quantif y th e effec t o n impingemen

t o f short-ter mreduction s i

n pum p operation . Despit e the lac k o f quantitativ e data , i

t i s concludedtha

t short-ter m(hourly or

daily ) reduction s i n th e volum

e of coolin g wate

r tha t coincide wit

h reducedgeneratio n hav e ahig h probabilit

y of reducin g entrainmen

t an dimpingemen

t losses . 7.2.6. 3 Seasona l Curtailmen t o f Energ y Productio n 

### Seasona l curtailmen

t of coolin g syste

moperatio n couldreduc e the number s o f organism s los t

b y entrainmen

t an dimpingement . Th e amoun t ofth e reduction depend s o n th e lengt h oftim e the coolin g syste

mi s ou t of operatio n an

dth e concentratio n of

organism s durin g the perio do f curtailment . Basedo

n th e seasona

l distributio n o f

entrainmen

t an dimpingemen

t (PG&E , 1983) , tw o pea k period s o f

abundance , Febmar

y through Marc

h (the pea k perio do f norther n anchovy , goby , an dsilversid e entrainmen

t i n 1978-1980 ) an

dAugus t through Septembe

r (th e pea k perio d of impingemen

t i n 1978-1980) , wer

e selecte da s possibl e period s fo r curtailment . Seasona

l curtailmen t o f coolin g syste

moperatio n wouldresult

i n areductio n i

n the number s of

organism s entraine dandimpinged , andi s therefor e considere dto b e a

n alternativ e technolog y fo r furthe r consideratio n fo

r th e ne w C C units . 7.2.6. 4 Alternativ e Biofoulin g Scheme s 

### Th e biofoulin g contro l procedur e currently use da

t th e Mos s Landin g Power

Plant consist s o f intermittent

chlorinatio n (Subsectio n 2.1.2 ) fo r slim e contro l an

dhea t treatment fo r biofoulin g control . Thes e contro l scheme s hav e been adequat e to contro l marin e growt

h andar e planne d fo

r applicatio n to th e new C C unit s a s well . Alternativ e biofoulin g contro l scheme s whic h ca n b e considere dfo

r applicatio n a

t th e new combine dcycl e unit s include th e following : 1 ; relocatio n o f

th e propose dchlorin e injection point fo r ne w c c unit s t o th e modified Unit s 1 throug h 5 intak

e hea dworks , 2 . increase dchlorin e dosage , 3 . increase dfrequency of

chlorinatio n fro

mintermitten

t dosag e to continuou s application , 4 . us e o f alternativ e chemica

l toxins , includin g bromine , chlorin e dioxide , chlorin e bromide , an dozone , 5 . applicatio n o f

toxi c coating s on coolin g systemconduit walls , E9-053. 9 7-1 7 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.7 3

7. 0 Evaluatio n o

f Altemative Intak

e Technologie s 

### 6 . oxygen depletio n (stagnation) , 7 . mechanica

l cleaning , 8 . increase dhea

t treatment , an

d 9 . increase dwater

velocitie s within coolin g syste mconduits . All ofthes e alternatives , wit h th e exceptio n o f

increasin g chlorinatio n frequenc y to continuou s applicatio n andincrease dwate r velocitie s within th e coolin g wate r conduits , are expecte d t

o hav e th e potentia

l of reducin g entrainmen

t croppin g by controllin g the colonizatio n o f coolin g water systemconduit s b y marin e fouling organisms . Becaus e ofth e toxicit y o f chlorin e t o no

n target organism s (entraine dfish eggs , larvae , an d juvenile s an

dinvertebrates) , continuou s chlorinatio n woul dpotentiall y result i n 10 0 percen t entrainmen

t mortality . Increasin g th

e velocit y o f coolin g water

through th e conduit s t

o level s abov e 1 0 fps (30 0 cm/sec ) ha s the potentia l o f reducin g colonizatio n by marine organisms . Increasin g coolin g wate r velocitie s would , however , substantiall y increas e mechanica l damag e t o entraine dichthyoplankto n an d macroinvertebrate s andincreas e impingemen t losses . Increasin g velocitie s withi n th e coolin g water conduit s i s therefor

e no t considere dt

o b e a n effective metho do f

reducin g th e combined losse s resultin g fro

mentrainmen

t an dimpingemen

t a t the ne w combine dcycl e .units . A s describe dearlier , th e propose dproject include s modification s t

o th e existin g Unit s 1 through 5 intak e systemt o allo w periodi c hea t treatmen t fo r remova l o f biofoulin g organism s afte

r th e ne w C C unit s are installed . Thi s ne w hea t treatmen t capabilit y shoul dreduc e th e level of predatio n o

n entraine dorganism s experience dwit h the histori c Unit s 1 throug h 5 operatio n an d n o furthe r change s to th e propose dsyste mshoul db e necessary . Further discussio n i s given in Subsectio n 7.3. 6 regardin g th e curren t anti-foulin g progra

mfo r Unit s 6 and7 a s well a s th e propose dprogra mfo r th e ne w C C units . 7.2.6. 5 Discharg e Temperature Regulatio n 

### Discharg e temperature s ar

e relativel y lo

w a t th e MLP P throughout

the year . I

n 1999 , th e annua

l averag e discharg e temperatur e wa s 69 ° F , wit

h apea k 24-h r discharg e temperature o f

81 0 

### F. ' Exposur e t o discharg e temperature s abov e 86 ° F (30 ° C ) durin g coolin g systemtransi t ar e letha l t o entraine dstripe dbas s larvae . Therefore , therma l stresse s ar

e no t expecte dto b e asignifican t caus e o f mortalit y t o entraine dfishe s o

r invertebrates . Discharg e temperatur e regulatio n i s not expecte d to resul t

i n asignifican

t reductio n i

n entrainmen

t losse s sinc e nearl y 10

0 percent ofth e organism s ar

e los t to biofoulin g predatio n i

n the coolin g syste

m(PG&E , 1983) .

i 199 8 NPDE S Discharge

r Self-Monitoring Repor

t fo r MLP P E9-053. 9 7-1 8 MLP P 316(b ) Resourc e Assessmen t 4-28-200 07. 0 Evaluatio n o f Alternativ

e Intak e Technologie s 7.2.6. 6 Coolin g Syste m Modification s 

### Stmctura l modificatio n o f

coolin g systemcomponent s (pumps , conduits , condensers ) i s not considere dto b e a

n effective alternativ e to reduc e th e mortalit y o f entraine dorganisms . To o littl e quantitativ e information i s availabl e t o isolat e specifi c source s of

mortalit y within acooling wate r system . Desig n parameter s fo r specifying pressur

e regimes , circulatin g water pum p design andoperation , tolerabl e shea r stresses , andcoolin g syste mdesign s fo

r minimizin g mechanica

l abrasio n hav e no t

bee n developed . 

### 7.2.7 Conclusion:

Biological

Evaluation Base do n result s ofth e biologica

l evaluatio n (Sectio n 7.2) , th e following wa s concluded : 1 . Ther e ar e no reasonabl e alternativ e intak e location s tha

t wouldreduc e entrainmen

t an d impingemen

t losses , 2 . Behaviora

l barrier s wouldnot

b e expecte dt

o reduc e number s of

organism s exposedt

o eithe r entrainmen

t or impingement , 3 . Entrainmen

t an dimpingemen

t losse s wouldno t

b e substantiall y reduce db y us e of travelin g screens , barrier

nets , aGunderboom , or

afish pum

p system , 4 . A screen mes h siz e o f

5/1 6 in . (0. 8 cm) i s acceptable ; ther e i s insufficien

t dataavailabl e t o determin e whethe

r th e surviva

l of fish egg s andlarva

e impinge don fine-mesh screen s woul dexcee dthe surviva

l of organism s entraine dthroug h th e MLP P coolin g systems , an d 5 . Coolin g systemstmctura l modification s an

ddischarg e temperatur

e regulatio n ar

e no t expecte dto reduc e the mortalit y of entraine dorganism s substantially . Th e following alternativ e intak e technologie s ma

y reduc e entrainmen

t and/o r impingemen

t losse s fo r th e ne w C C unit s andwer

e therefor e selecte dfo

r feasibilit y analysis : 1 . seasona

l curtailment

of coolin g syste

moperation , 2 . replacement

ofth e propose donce-throug h coolin g systemwit h aclosed-cycl e syste

m (either salt wate r coolin g tower(s ) or

air coole dcondensers) , 3 . modifiedvertica

l travelin g intak

e screen s an

dgravit y screenwas h fish retur

n syste mfo r th e revampe dUnit s 1 throug h 5 shorelin e intak e stmctur e t o b e use dfo

r th e ne w combined-cycl e units ,

E9-053. 9 7-1 9 MLP P 316(b ) Resourc e Assessmen t 4-28-200 07. 0 Evaluatio n o f Alternative Intak

e Technologie s 

### 4 . short-ter

mreduction s i

n circulatin g wate

r pum p operatio n when th e unit s ar e operatin g a

t lo w load s o r ar e ou t of service , 5 . periodi c dredgin g ofth e intak e are ato reduc e intak

e velocities , an

d 6 . alternativ e biofoulin g contro l schemes . 

## 7. 3 Third-Leve l Evaluatio n —Feasibilit y An d Cos t Analysi s Eac h alternativ e technolog y tha t satisfie dth e biologica

l reductio n criterio n (Sectio n 7.2) an d differe di n design or

operatio n fro

mtha t presentl y propose dfo

r th e new C C unit s coolin g wate r syste mwas evaluate dwit

h regar dt o engineerin g feasibility , operation , an dreliability . I

n addition , th

e tota l economi c cos t

i n 199 9 dollar s associate dwit h each feasibl e alternativ e wa s estimated . Cos t

estimate s reflec t

direc t capita l cost s an dindirec t cost s (e.g. , the los s of generatin g capacity ) wher

e applicable . 

### 7.3.1 Seasonal

Curtailment Sectio n 7.2.6. 3 identifie s seasona l curtailment

o f coolin g systemoperation s t o reduc e entrainmen

t an dimpingemen

t losses . Th e economi c consequence s o f seasona l curtailmen

t ar e suc h tha t Duk e Energ y woul dno t

constmc t aC C plant

tha t coul dno t operate fo

r fou r month s o f the year . I n thi s scenario , existin g Unit s 6 an d7 woul dcontinu e to operate a t high capacit

y level s i n th e absenc e o f

new , mor e efficien t generatio n a

t MLPP . Continue dus e o f Unit s 6 and 7 i n th e absenc e of

new generatio n woul dresult in greate r impingement/entrainment

sinc e th e impact s o f Unit s 6 and7 are greater

tha n th e propose dC C plant . Onc e th e CC plant

i s constmcted , seasona

l curtailment

ofth e ne w C C unit s wil l likely b e infeasibl e becaus e o f

increasin g deman dfo

r electrica l energ y in th e centra

l andnorther

n Californi aloa

dcenter s andth e uncertai n availabilit y o f surplu s energ y fro

mother source s to replac e it . Settin g asid e th e questio n o f alternativ e energ y source s t o reliabl y serv e customer s an d th e demandfo

r electricity , th e estimate dcost s o f replacement

energ y alon e tha

t would resul t fro mcurtailmen

t of operatio n ofth e new C C unit s fromFebmar y throug h March (th e pea

k perio do f norther n anchovy , goby , an

dsilversid e entrainmen

t fro mth e 197 9 -198 0 MLP

P 316(b ) study ) an d fro mAugus t through Septembe

r (th e pea k perio do f impingemen

t determine d from the sam e study ) ar e summarize di

n Tabl e 7-2 , base don expecte doperatio n ofth e new C C unit s an drecen t systempower

pric e projections . Th e estimate dnet los s o f futur e power sale s revenu e correspondin g t

o th e curtailmen

t o f ne w C C unit s operatio n durin g Febmar y throug h March plu s Augus t through Septembe

r i s about $5 9 millio n per

year . Fluctuatin g fue

l costs , which ar

e a majo r facto r i n the cos t o f replacemen

t energy , mak

e accurat e projection s o f

net futur e energ y E9-053. 9 7-2 0 MLP P 316(b ) Resource Assessmen t 4-28-200 07. 0 Evaluatio n o f Alternativ

e Intak e Technologie s

revenu e difficult . I f

curtailmen t

coul d b e implemente d durin g thes e tw o periods , i t coul d reduc e biological losse s resultin g fro mbot h entrainmen t an dimpingement . Thi s curtailmen t strategy , however , i s particularl y inappropriat e sinc e i t woul d severel y reduc e electrica l generatin g capacit y durin g th e critica l summe r perio d whe n electrica l deman d i s highest . A n altemativ e approac h t o usin g curtailmen t t o reduc e biological losse s i s t o schedul e maintenanc e outage s t o coincid e wit h period s o f greates t biological loss . However , i t i s inappropriat e t o schedul e maintenanc e durin g th e critica l summe r period . I t

ma y b e possibl e t o schedul e maintenanc e durin g Febmar y an d Marc h whe n electrica l load s ar e not a s hig h an d whe n othe r resource s suc h a s hydropowe r ar e mor e readil y available . However , schedule d maintenanc e outage s fo r

fossil-fuele d plant s ar e generall y o f muc h shorte r

duratio n tha n a t nuclear-fuele dplants , wher e thi s optio n ha s sometime s bee n considered . I t i s no t expecte dthat

frequen t significan t

schedule d outages for

th e ne w C C unit s wil l occur . Mino r maintenanc e outage s for cleanin g ofth e ne w unit s wil l b e schedule d fo r shor t periods , abou t fou r hour s o f downtime , approximatel y onc e pe r combustio n turbin e generato r (CTG ) uni t pe r month . Annua l inspection s wil l als o b e schedule d for eac h uni t tha t wil l requir e abou t

on e da y offlin e pe r

CTG . Mor e thoroug h inspections , requirin g abou t tw o days , wil l tak e plac e ever y thre e t o five years . Majo r overhauls , requirin g a

n outag e o f

abou t tw o weeks , typicall y occu r abou t ever y eigh t

years . Therefore , n o significan t biologica l benefit s coul d b e achieve d b y attemptin g t o schedul e maintenanc e outage s durin g predicte d sensitiv e periods . Dail y curtailmen t

o f coolin g syste moperatio n (e.g. , at nigh t o r whe n loa d i s low ) i s anothe r alternativ e approac h for

reducin g biologica l loss . I t i s likel y tha t

tha t th e ne w C C unit s wil l b e turne ddow n o r

som e CT G unit s take n offlin e durin g period s o f decrease d demand , suc h a s lat e evenin g an dearl y morning . However , thes e unit s wil l b e amon g th e mos t efficien t fossi l fue l unit s availabl e i n th e stat e syste man d ar e expecte d t o b e use d frequentl y t o mee t bas e loa d deman dda y an dnight . Therefore , althoug h i t i s expecte d tha t

th e ne w unit s wil l sometime s operat e at reduce dloa dwit h correspondin g benefit s t o marin e organisms , acommitmen t t o regula r curtailmen t

o f coolin g syste moperatio n i s considere d t o b e impractica l fo r th e ne w C C units , basedo n th e projecte dnee dfor highl y efficien t

source s o f

bas e loa d generatio n an d th e additiona l nee dfor

rapi drespons e t o electrica l demand s withi n th e system . Th e variou s strategie s for curtailmen t

o f coolin g syste moperatio n woul d resul t i n areductio n o f both entrainmen t

an dimpingemen t

losse s i n a

n amoun t tha t woul d depen d o n th e abundanc e o f organism s presen t

durin g th e perio d o f

curtailmen t

an d th e duratio n ofth e outage . However , curtailmen t

o f operatio n ofth e C C unit s beyon d wha t woul d occu r

fro mnorma l schedulin g i s no t acceptable , becaus e i t

remove s th e generatin g capacit y ofth e plan t fro mreliabl e servic e whe n i t i s neede dt o serv e syste mloads . Th e availabilit y o f replacemen t

powe r i s uncertain . However , i f

E9-053. 9 7-2 1 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.7 7

7. 0 Evaluatio n o

f Alternativ

e Intak e Technologie s 

### Unit s 6 an d7 wouldcontinu e to operat e i n lie u ofth e ne w generatin g facilitie s th e impact s o n impingement/entrainmen

t wouldb e greate

r fo r agiven level of

power generation . For the cost , operationa

l reliability , an

dflexibilit y reason s discusse dabov e relativ e t o th e potentia l improvement s i

n biologica

l impacts , curtailmen

t o f powe r generatio n a s ametho d o

f reducin g entrainmen

t an dimpingemen

t losse s fo r the ne w C C unit s i s not

considere dt

o b e a feasible alternative .

E9-053. 9 7-22 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.7 8

7. 0 Evaluatio n o

f Alternativ

e Intak e Technologie s Tabl e 7-2 . EstimatedCost of Replacemen

t Energy durin g tw o Period s o f Operation Curtailmen

t fo r the Mos s Landing Combined-cycl e Units . Perio d o f Curtailmen t Februar y Marc h Energ y Paymen t ($MW-hr) * 27.4 5 34.6 0 Fue l Cos t

(S/10 6 Btu)* * 2.5 2 2.4 8 Operatin g Tim e

(hrs/month)** * 60 5 67 0 Outpu tWhe n

Operatin g (MW)*** * 106 0 106 0 Los tRevenu e

($)**** * 6,614,00 0 4,713,00 0 Augus t Septembe r 55.3 5 45.7 5 2.4 6

2.4 8 67 0

65 0 106 0

106 0 27,429,00 0 19,902,00 0 Tota l 58,658,00 0 •Projecte d energ y price s fo r NYME X California-Orego n borde r for year 2000 , fromMegawatt

Daily, Dec . 22 , 1999 . ••Projecte d fuel cost s a

t NYME X Henry Hu b fro mGas Daily , Dec . 22 , 1999 . •••Estimate d operatin g tim e assumin g abou t 9 0 percen t

capacit y factor . ••••Los t energ y payment s les s avoide d cost s o f fue l (base d o n nomina l heat rat e fo r ne w C C unit s o f

6,80 0 Btu/kW-hr . •••••Revenu e contribution s mus t cove r al l operatin g cost s an d areturn on capital . 

### 7.3.2 Closed-Cycle

Cooling

Systems Potentiall y applicabl e system s a t th e MLP P include mechanica

l or natura l draf t recirculatin g coolin g tower s an

dai r cooledcondensers . Th e operatio n ofthes e system s i s describe di n Sectio n 7.2 . The following section s evaluat e th e cos t andfeasibilit

y a t MLPP . (The us e ofthes e system s woul db e preferred , fro mth e standpoin

t o f powe r plant operatin g economics , t

o th e seasona l curtailmen

t alternativ e discusse di

n the previou s section) . 7.3.2. 1 Mechanica l Draf t Coolin g Towe r 

### Tw o possibilitie s fo

r asourc e of

recirculatin g coolin g wate r exis t a t th e Mos s Landin g site , fresh groun dwate

r or seawater . Although freshwate r system s hav e th e advantag e o f smalle r makeu p wate r requirement s du e t

o les s dissolve dsolids , acontinuou s freshwate r makeu p supply o f

abou t 5,400 gpmwoul db e require dfo r afreshwate

r coolin g towe

r systemservin g th e ne w C C unit s a t MLPP . Du e to the curren

t an dexpecte dfutur

e limitation s o f

freshwate r supply i n th e area , i

t wa s decide dtha

t afreshwate

r systemwa s no t

realisti c andth e evaluatio n woul dconsider seawate r coolin g towers . Seawate r mechanica

l draf t coolin g tower s fo

r th e MLP P C C unit s woul dconsis t

o f tw o stmctures , one fo

r eac h unit , eac

h approximately 410ftx53ftx55f t high . Ocea

n wate r makeup fo r thi s systemwouldb e supplie dfro mth e existin g Unit s 6 and7 coolin g water pump s or new pump s a

t the existin g Unit s 1 through 5 pumpwell . The circulatin g water andblowdown

E9-053. 9 7-2 3 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.7 9

7. 0 Evaluatio n o f Alternativ e Intak e Technologie s strea mwoul dcontai n salinity (dissolve d solids ) approximatel y 5 0 percen t greate r tha n loca l seawater . Th e estimate dcombine dfull capacit y flo w rate s for bot h tower s are : Recirculatin g wate r

250,00 0 gp m Blowdow n (returne dt o 7,80 0 gp m ocean ) Makeu p (withdraw n fro m12,00 0 gp m ocean )
Th e blowdow n strea mwil l contai n residua l concentration s o f biocides , dispersants , an d othe r conditionin g chemicals , i n highe r concentration s tha n th e existin g once-throug h coolin g wate r discharge . Blowdow n wil l b e dispose d b y discharg e t o th e ocea n a t approximatel y 8 4 °F . Th e estimate dtota l installe dcapita l cost s associate d with th e tw o force d draf t mechanica l coolin g tower s fo r

th e ne w C C unit s includin g towers , basins , chemica l additiv e systems , an d supportin g system s ar e abou t S1 2 millio n mor e tha n th e propose d once-throug h coolin g wate r system. 2 Figur e 7- 1 show s apossibl e locatio n wher e th e ne w coolin g tower s coul d b e installe d at MLPP . Mechanica l draf

t coolin g tower s woul d significantl y diminis h th e ne t powe r outpu t an d operatin g efficienc y ofth e modernize dplant . Th e combinatio n ofth e highe r stea mturbin e condense r temperature s cause db y th e recirculatin g coolin g syste man d th e highe r plan t electrica l loa d compare dt o th e once-throug h coolin g wate r cas e woul d decreas e th e ne t powe r outpu t availabl e fro mth e ne w C C unit s b y abou t 2 5 M W (fo r

th e sam e fuel consumption) . Thi s reductio n i n capacit y wil l hav e t o b e mad e u p b y other , probabl y les s efficien t an d mor e pollutin g powe r sources . Th e estimate dannua l revenu e losse s fromthi s decreas e i n capacit y i s approximatel y $ 2 millio n pe r

year. 3 Ove r

th e lif e ofth e projec t

th e us e o f

coolin g tower s wil l cos t approximatel y $6 0 million . Visibl e fo g plume s coul db e expecte d (probabl y frequen t durin g th e winter ) du e t o condensatio n i n th e atmospher e ofth e considerabl e amoun t o f wate r vapo r emitte d fromth e to p o f

towers .

2 Amoun t show n i s th e additiona

l capita l investmen

t require d t o substitut e coolin g tower s fo

r th e propose donce throug h coolin g wate

r system . 3 Base do n ane t margin approximatel

y $ 10/MW-h

r an d a9 0 percen

t capacit y factor . E9-053. 9 7-2 4 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0Figure 3-2 . Conceptua l Locatio n fo r Mechanica l Draf t CoolIn g Tower s

a m•* » *« i DUKE/FLUQ R DANIEL ' no rn v ci c crxamc o CICL I <*n\ i*t.oi" c cc*«cc*iu»i . ot.tic « J L o»tr r Crxxif- C tc * 

### ^ r -.•r-h.-^. — Figur e 7-1 . Mos s Landin g Powe r Plan t alternativ e closed-cycl e coolin g mechanica l draf t coolin g towe r

location .

E9-053. 9 7-2 5 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.8 1

7. 0 Evaluatio n o

f Alternativ

e Intak e Technologie s 

### Coolin g towe

r drif t "raining " ou

t ofth e plum

e coul dcaus e anuisanc e salt water depositio n o

n the surroundin g are awhic h coul dresult i n increase dequipmen

t maintenanc e requirement s i n the plant andadvers e effects on nearb y agriculture , an da t time s o n loca l businesse s an

dresidences . Drif t woul d als o lea

dto increase dfine particulat e salt emission s fro

mth e facilit

y i n th e for mo f dissolve dsolid s emitte dwit h th e drif t droplets . For

th e sal t wate r towe r considered , the estimate dadditiona

l particulate emission s t

o the atmospher

e associate dwit

h drif t wouldb e abou

t 75 0 lb/day . Thi s quantit

y wouldrepresen

t asubstantia

l increas e i

n PM1 0 emission s fromthe projec t and coul dcaus e advers e ai r qualit y impacts . Mechanica

l coolin g tower s ar

e asignifican

t potentia l sourc e of

overall power

plant nois e impact s on surroundin g area s du e to th e significan t quantit y of elevate dequipmen

t suc h a s fans , motors , an dgears . For all th e abov e reasons , th e propose donce-through coolin g wate r syste mi s preferre dt

o a mechanica l draf t tower . 7.3.2. 2 Natura l Draf t Coolin g Towe r 

### A natura l draf t coolin g towe

r syste mi s ver y simila r i n principa l t o the mechanica

l draf t system . Th e primar

y differenc e i s tha

t th e mechanica

l fan s t o mov e th e coolin g air

are replace dby wha

t i s essentiall y aver

y larg e chimney . Ai

r i s draw n i n a t th e bas e ofth e towe

r du e t o th e les s dens e (mor e buoyant) , warme

r air exitin g th e to p ofth e tower . Thi s natura l air circulatio n contact s th e returne dcoolin g wate

r inside the towe

r andcool s the wate

r by evaporatio n anddirec t

contac t wit h th e cooler

air . Thu s th e coolin g wate r recirculation , blowdown , an dmakeu p rate s an d qualit y ar e about th e sam e a s fo r the mechanica

l (forceddraft

) system . A natura l draf t coolin g towe

r t o serv e the Mos s Landin g combined-cycl e unit s woul db e approximatel y 25 0 fee

t i n diamete

r a t th e bas e andabout

37 0 fee t in height . Figure 7- 2 show s a conceptua l locatio n fo

r th e ne w natura l draf t coolin g tower . The estimate dtota

l installe dcos t

fo r natura l draf t towe r i s abou t $1 3 millio n mor

e tha n th e propose d onc e throug h coolin g wate r system

5

4 Assuming drif

t i s 0.0005 % o

f recirculatin g water . 5 Incrementa

l capita l investmen

t fo r natura l draf t cooling towe

r i n lie u o f proposed once-throug h coolin g wate r system . E9-053. 9 7-2 6 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0Figur

e 7-2 . Mos s Landin g Powe r Plan t alternativ e closed-cycl e coolin g natura l draf t cooling towe

r location .

E9-053. 9 7-2 7 MLP P 316(b ) Resourc e Assessmen t 4-28-200 07. 0 Evaluatio n o f Alternativ

e Intak e Technologie s 

### Mos t of the potentia

l negativ e impact s describe dfo r th e mechanica

l draf t tower s woul dals o b e associate dwit

h ane w natura l draf t tower fo r th e MLPP . The blowdow n discharg e to th e ocea n would b e th e same . Drif

t losse s an dth e resultin g PM1 0 emission s woul dals o occur , althoug h a t somewha t reduce drates . Nois e impact s woul db e less . Th e auxiliar y powe r requirement

would b e reduced , due t

o th e lack of mechanica

l fans , bu t the stea mturbine s output

woul dstil l b e decrease db y abou

t 2 2 MW . Th e estimate dannua l revenu e losse s fro

mthi s decreas e i n capacit

y ar e approximately $1. 7 millio n pe r year. 6 

### Ove

r the 30-yea

r lif e ofth e projec t

th e us e ofanatura

l draf t coolin g towe

r will increas e powe

r cost s by approximately $5 1 million . Visibl e condensat

e plume s wouldals o periodicall y occu r a t th e top ofth e tower

and , obviously , th e overall visua

l impac t du e t o th e siz e ofth e towe

r i s muc h mor e significant . Thi s alternativ e wa s eliminated , primarily becaus e ofth e ver y advers e visua

l impact s o f

suc h a massiv e stmctur

e an dthe high capita

l investmen

t required . 7.3.2. 3 Air-coole d Condenser s 

### Air-coole dcondenser s fo

r powe r plant s ar e ver y larg e stmcture s andconsum e significan

t amount s of

powe r fo r operatio n ofth e fans . Nois e impact s ar e substantia

l and , without

extensiv e abatement , ar

e generally greate

r tha n fo r mechanica

l towers . Air

coole dcondenser s als o significantly reduc e stea

mturbin e output

du e to highe

r condensin g temperature s a s compare d t o once-through or

recirculatin g wate

r condensers . I t i s estimate dtha

t a n air-coole dcondenser s fo

r th e ne w C C units , on e fo

r eac h unit , woul d each occup y abou

t 0.7 5 acr e o f plo t space , exten dto aheigh

t o f 8 0 to 9 0 feet . Overall , th e net output fo r th e tw o new C C unit s woul db e reduce db y atota l o f mor e tha n 6 0 MW 7 

### (th e siz e ofasmall powe r plant) . Figur

e 7- 3 show s th e plo t

spac e tha t woul db e consumed .

6 Base do n ane t margi n of $ 10/ M W-h r an d a9 0 percen

t capacit y factor . 7 Fo r summertim

e operation ; th e correspondin g reductio n fo r wintertim e operatio n i s about

3 7 MW . E9-053. 9 7-2 8 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0Figur e 3-4 . Conceptua l Locatio n fo r Ai r Coole d Condenser s 

# f S DUKE^FLUQ R DANIEL ' cowi'ur j cict C COXCIuA L OISIC H * l » COO,( a CC*OOrtI « O rI I mjj?t i Figur e 7-3 . Mos s Landing Powe r Plan t alternativ e closed-cycl e coolin g air-coole d condenser s location .

E9-053. 9 7-2 9 MLP P 316(b ) Resourc e Assessmen t 4-28-200 07. 0 Evaluatio n o f Alternativ e Intak e Technologie s



### The estimate d additiona

l tota l installe dcos t

fo r the tw o ai r cooledcondensers , a s compare d t o the propose d onc e throug h coolin g syste mi s abou t $3 0 millio n combine dtota l cost s fo r bot h the CC units . Th e estimate dannua

l revenu e losse s fro

mth e associate ddecreas e i n capacit y i s abou t Q 

### $3. 8 millio n pe

r year . Ove

r th e 30-yea

r expecte dlif

e ofth e projec t

th e us e ofai r

cooled condenser s wouldcos t

abou t $11 4 million . Becaus e ofth e substantia

l los s i n ne t powe r output , th e significan

t advers e visua

l impact s o

f thes e systems , an

dthe ver y larg e associate dcosts , the air-coole dcondense r optio n i s eliminate d fro madditiona

l consideration . 

### 7.3.3 Modified

Vertical

Traveling

Screen and Fish Return System for the New CC Units Intake A s describe di

n Sectio n 2 , th

e existin g (retired ) Unit s 1 through 5 intak e stmcture will b e modifiedt o serv e a s ashorelin e intak e stmctur e (incline dscreen s i

n the shorelin e stmcture ) fo r th e ne w C C units . Thi s shorelin e intak e stmctur e wil l eliminat e th e larg e lengt

h of intak e conduit upstrea mofth e screen s an

dth e lowe r coolin g wate

r withdrawa

l rate s will result

i n decrease dintak

e velocities , bot

h of which shoul dsubstantially reduc e entrapment o f organism s withi n the intak

e conduit , as comparedt

o the previously usedintak e configuration . The intak e stmcture an

dscreen configuratio n will b e designedfo r ascree n approac h velocit

y o f 0. 5 fps (1 5 cm/sec ) a t mea n lowe r lo w water , which i s consisten t wit h U.S . EP A guideline s fo

r th e design o

f new coolin g wate

r intak e stmctures . A

t highe r tide levels , which wil l b e mos t ofth e time , the screen approac h velocit

y will b e less . Thi s alternativ e evaluate s the us e ofavertica l travelin g scree

n wit h fish handlin g feature s instea d ofth e propose dincline dscreen . Fo r som e specie s of

fishes , impingemen

t mortalit y ca n b e reduce dthroug h stmctura

l modification s t

o conventiona

l vertica l travelin g screen s an

dachang e i n intak e screen operatio n fro

mintermittent

to continuou s rotatio n (Subsectio n 7.2) . Th e stmctural difference s to th e currently propose dmodification s fo r th e ne w C C unit s fo

r thi s alternativ e woul dinclude replacemen t o f th e propose dincline dscreen wit h aconventiona

l vertica l screen , installatio n of

watertigh t fish collectio n basket s alon g th e screen , bot h low

pressure andhigh-pressur

e wash systems , an

dafish retur

n sluiceway . A differentia

l contro l an

d two-spee dmotor

ar e als o included , s o tha

t whe n th e scree n i s operate dcontinuousl y it rotate s a t slo w speed , an

da s th e o f numbe r fishes and/or

debri s load s increase , th e screen rotatio n rat e ca n b e automatically increased . I n general , 3/8-in . (0.9-cm) scree n mes h woul db e use don modified vertica l travelin g screens .

8 Base do n ane t

margi n o f

$10/MW-h r

an da9 0 percen t

capacit y facto r

an d assumin g a n annua l averag e capacit y reductio n o f

48. 5 MW . E9-053. 9 7-3 0 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.8 6

7. 0 Evaluatio n o

f Alternativ

e Intak e Technologie s 

### Screen s modifiedto reduc e impingemen t mortalit y nee dt o b e accompanie dby asluicewa y (Subsectio n 7.2 ) designe dt o retur n impinge dorganism s t

o th e receivin g waterbody . Most installation s of

modifie dtravelin g screen s us e adua l sluicewa y retur n system , agravit

y sluicewa y retur n syste mfo r impingedorganism s removedfro mth e screen s by th e low-pressur e spraywas h an

danothe r sluicewa y fo r debri s removedb y the high-pressur e spraywash . The alternativ e modifiedscree n syste mevaluate dfo

r th e CC unit s intak

e stmcture i s show

n i n Figure s 7-4 an

d7-5 . Thi s syste

mwouldconsis t

o f ne w vertica l screen s installe di

n th e existin g Unit s 1 through 5 intak

e stmctur e behindthe existin g ba

r racks . The screen s wouldb e smoot h top mesh an

dfurnishedwit

h fiberglass fish basket s anddifferentia l speedcontrols . Low an

d high-pressur

e spra y was h system s ar

e provide dt

o wash recovere dfish an

dothe r organism s int

o a fish troug h o n th e top ofth e intak

e stmcture . Impinge ddebri s will b e washedint o aseparat e

E9-053. 9 7-3 1 MLP P 316(b ) Resource Assessmen t 4-28-200 07. 0 Evaluatio n o f Alternativ e Intak e Technologie s P.8 7

., — NE W TRAVELIN

G SCREE N

STO P LOG S

Figur e 7-4 . Travelin g wate r scree n proposa l numbe r 1 .

,- riS M RETUR N TROUG H <COVERED >

. CKTCNO & fRO U MTAK E STRUCTUR E T O HARIJO R A

T COAST MCMWA

T BRVC C

DC8PJ S COLLECTIO N CONTAtNC R
Figur e 7-5 . Travelin g wate r scree n proposa l numbe r 1 (overhea

d view) . debri s trough , als o o n to p ofth e stmcture . A ne w wate r filled fis h sluicewa y woul d exten d fro m th e fish troug h t o Mos s Landin g Harbo r t o retur n recovere d organism s t o th e Harbo r a t th e shorelin e approximatel y 80 0 feet nort h ofth e intak e stmcture . E9-053. 9 7-3 2 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.8 8 

# I I

! 

# I I 1 I I I I I I 

# I I I 1 I 1 i 7. 0 Evaluatio n o f Alternativ

e Intak e Technologie s Fo r th e ne w C C units , th e incrementa l capita l cost s of amodifie d scree n ar e thos e associate d with th e differenc e i n cos t fo r avertica l scree n plu s th e fish handlin g modification s an d fish conveyanc e syste ma s compare dt o th e propose d incline d scree n system . Modificatio n ofth e propose dincline dscreen s t o vertica l intak e screen s with th e additional feature s describe d fo r fish handlin g (fis h baskets , deflectors , dua l spraywas h system , differentia l controls , fish retur n system , etc. ) woul dhav e a n incrementa l capita l cos t o f approximatel y $2. 6 millio n mor e than th e propose dincline dscree n system . 

### 7.3.4 Reductions

in Circulating

Water Pump Operation A reductio n i n th e numbe r o f circulatin g wate r

pump s in operatio n i s a

n operationa l strategy fo

r reducin g coolin g wate r

volum e us e an d intak e approac h velocities , an d henc e th e rate s o f entrainmen t

an dimpingement . Th e currentl y propose dconfiguratio n ofth e ne w combined-cycl e unit s wil l allo w reduce d coolin g wate r

pum p operatio n durin g certai n reduce d load operatin g scenarios . A s describe d in Sectio n 2 , th e presentl y propose dne w facilitie s consist o f tw o essentiall y independen t 53 0 M W units . Eac h uni t

i s provide dwith tw o CTG/HRS G trains , whic h suppl y stea mt o on e steam turbin e generato r

(STG)/condense r

set . Onl y th e ST G condenser s requir e th e us e o f significan t amount s o f

coolin g water . Th e STG s ar e provide d for th e sol e purpos e o f

recoverin g (i n essenc e recycling ) exces s hea t

fro mth e combustio n turbine s t o creat e additional energy , an d thereb y ar e asignifican t

reaso n for

th e very hig h therma l efficienc y ofth e combine d cycl e process . Thre e coolin g wate r

pump s pe r

53 0 M W uni t

wil l suppl y coolin g wate r t o th e condense r

i n th e uni t the y serv e ( atota l o f

si x ne w coolin g wate r

pump s fo

r th e entir e 1,06 0 M W addition) . I f onl y on e ofth e tw o ne w unit s i s operating , onl y thre e ofth e si x ne w coolin g wate r pump s woul d m n t o serv e it . I n certai n othe r operatin g condition s i t

ma y b e possibl e t o als o reduc e coolin g wate r flo w rates . Fo r

example , i f

on e uni t i s operatin g at

significantl y reduce d capacit y suc h a s onl y on e ofth e tw o CTG/HRS G train s o n line , i t ma y possibl e t o satisfactoril y operat e tha t uni t wit h onl y tw o o f

it s thre e coolin g wate r

pump s operating . Anothe r approac h t o reduc e coolin g wate r flow s t o th e minimu mleve l necessar y t o maintai n efficien t operatio n ofth e uni t

a t aspecifi c generatin g loa d woul d b e t o instal l variable-flo w pump s o r modif y th e existin g pump s t o incorporat e variabl e features . Sinc e th e combined-cycl e unit s ar e expecte dt o m n near,ful l capacit y for mos t ofth e year , whic h dramaticall y reduce s th e potentia l benefit s o f

variabl e flo w devices , thi s alternativ e wil l not b e evaluate d for

th e ne w units . A s discusse dabove , it wil l b e possibl e t o reduc e th e numbe r o f C C uni t coolin g wate r pump s i n operatio n fro msi x t o a s few a s tw o durin g par t loa d condition s which , i n effec t i s a variabl e flo w capability . Unit s 6 an d 7 ar e expecte d t o operat e a t reduce d load s mor e frequentl y

E9-053. 9 7-33 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.8 9

7. 0 Evaluatio n o f Alternativ e Intak e Technologie s i n th e future especiall y durin g lowe r deman d periods . Therefore , th e us e o f variabl e flow was analyze dfor

th e existin g units . Th e pump s currentl y i n us e for Unit s 6 an d 7 ar e limite d t o no-flo w o r full-flo w operation . Sinc e eac h pum p serve s onl y one-hal f o f it s unit' s spli t

condense r

an d th e stea mfromth e steamturbin e flow s t o both halve s ofth e condenser , both pump s mus t m n whe n th e uni t

i s operating , eve n a

t reduce dloads . However , wit h variable-frequenc y control s o r variabl e flow vane s th e Uni t 6 an d 7 pump s coul db e operate da t coolin g wate r

flow rate s tha t

matc h reduce d uni t

loads , reducin g th e number s o f

organism s entraine d an d impinged . Th e magnitud e ofth e reduction s in entrainmen t

an dimpingemen t

losse s woul d depen d o n th e reductio n i n coolin g wate r flows an d th e abundanc e o f

organism s a

t th e time s whe n syste mdeman d allowe d operatio n ofth e circulatin g wate r

pump s a t reduce dflow rates . Thre e type s o f

variabl e flow technologie s wer e considere d for retrofi t applicatio n o n th e Unit s 6 an d 7 pumps , variabl e frequenc y driv e (VFD) , variabl e vanes , an d multipl e spee d drive . VF D was selecte da s th e preferre dchoice , base d o n experienc e o f application , complexit y o f operation , an davailabilit y o f suppliers . A VF D modificatio n woul d consist o f replacemen t

o f th e existin g pump s an dmotor s with ne w pump s an d heav y dut y motor s with a n upgrade d moto r coolin g syste ma s wel l a s ane w VF D uni t for eac h pump . Th e VF D uni t varie s th e frequenc y o f electrica l curren t

t o th e pum p motor , an d therefor e it s rotationa l speed , based o n th e flowrat e required . Th e estimate dtota l installe dadditional 9 capita l cos t ofth e VF D modification s for th e four coolin g wate r

pump s at Unit s 6 an d7 , includin g ne w pumps , ne w motor s an d fou r ne w VF D unit s i s approximatel y $3. 6 million . Reductio n o f

coolin g wate r

flow durin g reduce d loa d operatio n wil l decreas e th e thermodynami c efficienc y ofth e stea mcycl e du e t o highe r condense r

outle t temperatures , whic h wil l resul t i n les s powe r

generatio n for

afixedfuel firing rate . Reductio n o f coolin g wate r

flow i s als o limite d t o th e exten t

tha t th e condense r

tube s nee d t o b e flooded with coolin g wate r for prope r operatio n o f th e stea mturbin e generators . Base do n th e likel y margina l entrainment/impingemen t benefit s du e t o th e limitation s for reducin g coolin g wate r

flow at reduce d load s for

Unit s 6 an d 7 , th e significan t capita l investmen t required , an dgeneratio n efficienc y penalty , th e variabl e flo w alternativ e i s no t considere d further .

9 As describe d i

n th e project AFC , the existin g Unit s 6 an d 7 cooling wate

r pump s have deteriorate d du e t o ag e an d will b e replace da s par

t ofth e propose d project . I

t i s presently planned t

o replac e th e existin g pump s wit h ne w conventiona

l constan t flo w pumps . The cos t

indicated her

e i s the incrementa

l cos t t o install ne

w VF D pump s instea dofth e ne w constan t flo w pumps . E9-053. 9 7-34 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.9 0

7. 0 Evaluatio n o f Alternativ e Intak e Technologie s 

### 7.3.5 Dredging

the Intake Area Sedimen t depositio n durin g norma l operatio n o f th e coolin g wate r

system s ofth e Mos s Landin g Powe r Plan t graduall y occur s i n Mos s Landin g Harbo r i n front ofth e plan t

an d adjacen t

t o th e are aofth e intak e bar

rocks . Pas t

sedimen t depositio n ha s cause d adecreas e i n th e cross sectiona l are aofth e intak e forebay s an d acorrespondin g increas e i n intak e approac h velocities . Periodi c dredgin g ofth e intak e are aa s neede d i s expecte d t o reduc e intak e velocitie s an d thu s th e potentia l numbe r

o f fishe s impinged , an d t o increas e th e operationa l efficienc y ofth e pumps . Th e MLP P ha s institute daregula r progra mo f

intak e velocit y measuremen t t o determin e whe n dredgin g i s neede di n fron t ofth e coolin g wate r

intake s t o decreas e approac h velocities ; Intak e velocit y measurement s ar e take n at leas t annuall y an d correctiv e dredgin g schedule d a s needed . Sinc e thi s progra mi s ongoin g an dwil l b e expande d t o includ e th e ne w C C unit s intak e in th e future , n o furthe r

consideratio n o f

dredgin g i s warranted . 

### 7.3.6 Alternative

Biofouling

Treatment

Schemes Chlorinatio n an dhea

t treatmen t

ar e currentl y use d at

th e MLP P i n a

n effor t t o contro l slim e accumulatio n o n condense r surface s an d colonizatio n ofth e coolin g wate r system s b y macroinvertebrate s suc h a s barnacles , mussels , an d hydroids . Dat afro mth e 197 9 intra-cooling-syste mmas s balanc e stud y at Unit s 1 throug h 5 (Tabl e 3- 5 o f PG&E , 1983 ) sugges t

tha t substantia l losse s o f

entraine d larva l fishe s b y macroinvertebrate s may hav e occurre di n thi s coolin g wate r intak e condui t

prio r t o th e retiremen t

o f thos e units . Thi s predatio n probabl y occurre dbecause , historically , i t was onl y possibl e t o remov e macroinvertebrate s throug h hea t treatin g i n th e portio n ofth e intak e syste mfro mth e pumpwel l t o th e condensers . Colonizin g organism s wer e not regularl y remove d i n approximatel y 35 0 fee t o f intak e condui t

betwee n th e pumpwel l an d th e shoreline . Hea t treatmen t

ofth e Unit s 6 an d7 coolin g wate r system , accomplishe d b y recirculatio n o f warm condense r

outle t water , i s use dt o contro l macroinvertebrate s betwee n th e condense r outle t gate s an dth e intak e inle t

gates . Equipmen t

include d i n th e hea t

treatmen t

involve s th e inle t

tunne l fro mth e inle t

gates t o th e condense r

outlet gates , circulatin g wate r

pump s an d travelin g screens . Th e curren t

NPDE S Permi t

require s th e followin g biofoulin g controls : "Fo r Unit s 6 an d7 (discharg e 002) , hea t

treatment s wil l b e conducte d approximatel y onc e ever y on e t o fou r month s i n eac h ofth e fou r

conduits. " I n addition , "th e maximu mtemperatur e ofth e discharg e shal l no t excee dth e natura l temperatur e ofth e intak e wate r b y mor e tha t

40 ° F (22.2 ° C). " A t

a minimum , twelv e heat

treatment s ar e conducte d ayea r wit h th e maximu mbein g 4 8 ayear . A t th e minimu mo f

1 2 hea t treatment s pe r

year , a t amaximu mtemperatur e o f 40 ° F abov e th e natura l temperatur e ofth e intak e for tw o hours , th e discharg e wil l b e impacte d wit h 2 4 hour s a E9-053. 9 7-3 5 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.9 1

7. 0 Evaluatio n o

f Alternativ

e Intak e Technologie s yea r o f 40 ° F above th e natura l temperatur e ofth e intak e an d at 4 8 hea t treatment s th e impac t wil l b e 9 6 hours . In additio n t o heat

treatment , 1 4 -1 6 w t

percen t sodiu mhypochlorit e (bleach ) solutio n i s injecte d periodicall y int o th e circulatin g wate r tunnel s jus t

afte r th e travelin g screen s for contro l o f

micro

foulin g (microscopi c alga e an dbacteri agrowth ) o n condense r surfaces . Th e curren t

dosag e at Unit s 6 an d7 i s approximatel y 2 0 minute s pe r tunne l thre e time s pe r

day fo r atota l o f approximatel y 6 0 minute s pe r da y pe r tunnel . Residua l chlorin e level s a t th e discharg e ar e les s than 0. 2 mg/l a s require db y th e NPDE S permit . Treatmen t

period s an dfrequencie s for th e ne w combined-cycl e unit s wil l b e simila r t o thos e use d fo r Unit s 6 an d7 with th e possibilit y o f som e dosag e adjustment s a s necessar y whe n th e unit s com e o n line . I

t i s currentl y planne dt o injec t hypochlorit e solutio n a

t th e inle t t o th e ne w C C condenser s rathe r

than a t th e suctio n ofth e coolin g wate r pump s a s currentl y practice d for Unit s 6 an d 7 . A s describe din Sectio n 2 , th e propose d modification s t o th e existin g Unit s 1 throug h 5 intak e syste mto accommodat e th e ne w C C unit s includ e interna l stmctura l change s t o allo w hea t treatmen t o f th e entir e coolin g wate r

suppl y condui t

syste mfro mth e shorelin e intak e t o th e condense r

inlet . I t i s expecte dtha t

th e hea t treatmen t

procedure s an d schedule s fo r th e ne w C C unit s coolin g wate r

syste mwil l b e simila r

t o thos e currentl y use d for Unit s 6 an d 7 . Thi s ne w heat treatmen t

capabilit y for

th e entir e lengt h o f

inle t condui t shoul d correc t

th e observe d entrainmen t

losse s durin g th e histori c operatio n o f Unit s 1 throug h 5 an d furthe r consideratio n o f alternat e biofoulin g control s i s not warrante d a t

thi s time . 

## 7. 4 Summar

y an d Conclusion s Th e preliminar y biologica l benefits , costs , an d engineerin g constraint s ofth e alternativ e intak e technologie s considere di n Sectio n 7. 3 ar e summarize d below . O n th e basi s o f thi s information , arecommendatio n i s mad e a s t o th e bes t intak e technolog y availabl e fo r th e ne w combined-cycl e units . A n examinatio n wa s mad e ofth e relativ e effec t o f operatio n ofth e plant' s coolin g wate r syste m o n fish an dmacroinvertebrat e populations . A s th e field studie s o f intak e effect s nea r

completion , n o evidenc e ha s bee n foun dt o indicat e tha t coolin g wate r

syste moperation s ofth e ne w combined-cycl e an dexistin g MLP P generatin g unit s wil l resul t i n a n advers e impac t

o n th e population s offis h an dinvertebrate s inhabitin g Mos s Landin g Harbor , Elkho mSlough , an d Montere y Bay . Mos t

ofth e organism s entraine d an d impinge d wer e specie s tha t ar e distribute d widel y b y bot h ocea n current s i n Montere y Ba y an d alon g th e Pacifi c coast , an d b y th e larg e tida l
E9-053. 9 7-36 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.9 2

7. 0 Evaluatio n o f Alternativ e Intak e Technologie s 

### exchang e i n Mos s Landin g Harbor-Elkhor n Slough . The broa

dexten t an dmovemen

t ofthes e specie s along th e coas t

reduce s the risk

o f localize dpopulatio n effects . I n addition , the specie s whos e larva

e ar e entraine dtypically have ver y hig h natura l mortalit y rates . Th e overwhelmin g majorit y ofth e number s offis h larva e entraine dt

o dat e i s represente dby specie s of no commercia

l or recreationa

l value . Non

e ofth e entraine do

r impinge dspecie s ar

e protecte d o

r o f specia l concern . Fo r thes e reasons , i

t wa s conclude da

t thi s tim e tha t th e impact ofth e existin g an

dpropose d modernize dMos s Landin g Powe r Plant' s operatio n o

n marine lif

e ha s bee n an dwill continu e t

o b e undetectable , an

dtha t there i s n o certaint

y tha t implementatio n o f

alternativ e intak

e technologie s designe dt

o furthe r reduc e entrainmen

t o r impingemen

t mortalit y wouldresult

i n a detectabl e increas e i

n populatio n abundanc e fo

r fish an dinvertebrat

e specie s inhabitin g the Montere y Ba y regio n an

dth e adjacen

t coasta l waters . Th

e recommendation s an

ddiscussio n o

f alternativ e intak

e technologie s presente dher e ar e basedi n par t o n thi s conclusion . 

### 7.4.1 Discussion Alternativ e intak

e technologie s considere dfo r the ne w CC unit s include : 1 . seasona

l curtailmen

t of coolin g syste

moperation , 2 . closed-cycl e coolin g systems , 3 . fish collectio n modification s ofth e proposedintak e screens , andscreenwas h sluicewa y retur n system , 4 . reduction s i

n circulatin g wate

r flow rates , 5 . periodi c dredgin g ofth e intak e area ; an d 6 . alternativ e biofoulin g contro l schemes . Each ofthes e alternative s i s expecte dt o offe r som e potentia l fo r reducin g th e losse s of organism s b y entrainment

and/or impingement . Curtailmen

t o f coolin g systemoperatio n wouldresult i n reduction s o f

bot h entrainment

an d impingemen

t losses . The level of

reductio n woulddepen

do n th e abundanc e o f

organism s present durin g th e perio do f

curtailmen

t andthe duratio n ofth e curtailment . Th e economi c consequence s o f

thi s alternativ e ar

e s o sever e tha t Duk e Energy wouldprobably abando n th e CC unit s project . Thi s scenari o wouldresult i n the associate dimpact s o f highe r cos t andles s reliabl e electricit y fo r Californi aconsumer s an

dincrease doperatio n o f

Unit s 6 and7 , which requir e significantly mor

e coolin g wate

r pe r MW-h r generated , an

dhav e greate

r marin e impacts , tha

n th e propose dC C units . Therefore , curtailmen t of powe r plan t operatio n a s ametho dof

reducin g entrainmen

t andimpingemen

t i s not afeasible alternative . E9-053. 9 7-3 7 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.9 3 

# I 1 1 1 I I 7. 0 Evaluatio n o f Alternativ e Intak e Technologie s



# 1 1

1 1 I 1 Closed-cycl e coolin g option s (mechanica l draf t coolin g towers , natura

l draf t coolin g tower , an

d ai r coole dcondensers ) wer

e eliminate do

n th e basi s of

unacceptabl e environmenta l impact s an

d constmctio n an

doperatin g costs . Drif

t droplet s an

dsolid s "raining " ou

t ofth e coolin g towe

r plume s coul dcaus e anuisanc e liqui ddepositio n o n th e surroundin g are aan

dsignifican

t additiona l particulate emissions . Potentia l impact s t o loca l agricultur

e an dequipmen

t would occu r fro mdepositio n ofthes e drif

t salts . Mechanica

l draf t coolin g tower s andair

cooled condenser s ar

e asignifican

t potentia l sourc e o f

overal l powe

r plan t nois e impact s o

n surroundin g areas . All thre e closed-cycl e alternative s significantly reduc e plant output due , primarily , t

o reduce dstea

mturbin e generator

efficiency , and , secondarily , t o increase dinterna

l plan t loads . Likewise , all thre e option s wouldresult i n significan

t visua l impacts , particularl y the natura l draf t tower . For

all th e abov e reasons , the propose donce-through coolin g wate r syste mi s preferre d to aclosed-cycle dcoolin g systems . Modification s ofth e propose dincline dtravelin g screen s fo r th e refurbishedshorelin e intak e stmcture t o include vertica

l travelin g screens , fish buckets , alow-pressur e spraywas h syste

man d gravit y screenwas h sluiceway , wit h provision s fo

r continuou s rotatio n hav e th e potentia l fo r increasin g impingemen

t surviva l o f surfperc h an drockfish . Impingemen

t surviva l of specie s suc h as norther

n anchovy an

dtopsmelt probably wouldno

t b e improve dby us e o f

modifie d intak e screens . Incorporatio n o f screen modification s an

dafish retur

n systemi n the ne w CC unit s intak e coul dreduc e impingemen t mortalit y u p t o 1 0 percen

t basedo n the percent compositio n o f

recoverable , impinge dspecies . Additiona l mortalit y resultin g fro

mpassag e through th e fish retur

n system , includin g increase dsusceptibilit y to diseas e an

dpredatio n a

t th e sluicewa y discharge , woul dreduc e th e expecte dbiologica l benefit s o f

thi s alternative . Th

e estimate d incrementa

l capita l cos t of modifying th e intak

e screen s t o include fish-handling facilitie s wbul d b e approximately $2. 6 millio n (199 9 dollars ) mor e tha n th e propose dincline d travelin g screen system . Neithe r the additiona

l indirec t O& M cost s nor

th e cost s of

engineerin g studie s tha t wouldb e neede dto ensur

e reliabl e intak

e scree n performanc e unde

r periodi c hig

h detrita l loadin g wer

e quantified , becaus e ofalac k o f industry-wide experienc e wit h modified intak e screen s unde

r such conditions . Consideratio n wouldals o nee dt o b e given t

o th e potentia

l aestheti c problem , bot

h visua l ando f odor , create dby retur

n of organism s tha

t di dnot surviv e impingemen

t t o th e confine s o f

Mos s Landin g Harbor . Becaus e ofth e low impac t of impingemen

t losse s an dth e relatively high cost s involved , installatio n ofthes e modifiedintak e screen s and fish retur

n fo r the ne w C C unit s i s no

t recommended . Reductio n i

n circulatin g wate

r pum p operatio n t

o coincide wit

h period s o f

reduce delectrica

l generatio n o

r whe n aunit i s ou t of servic e ha s als o been identifieda s abiologicall y effective metho dof reducin g the losse s o f

organism s through entrainmen t an dimpingement . The Mos s Landin g Powe

r Plan t ca n b e operate da

t reduce dload s wit

h les s tha n ful l circulatin g wate

r flow, either through removin g pump s fromservic e or throug h installatio n o f

variable-spee dmoto

r E9-053. 9 7-38 MLP P 316(b ) Resource Assessmen t 4-28-200 07. 0 Evaluatio n o f Alternativ

e Intak e Technologie s 

### controls . Reducin g coolin g wate r flow durin g extende dunit

outage s i s standar

doperatio n a

t the plan t an dwil l b e practice dfo

r th e ne w C C units . Th e estimate dincrementa l installe dcapita

l cos t o f variabl e speedmotor s an

dcontrol s fo

r Unit s 6 and7 , i

n additio n t

o th e upgrade s alread

y propose d in th e project , i s abou t $ 4 million . Thi s cos t

i s considere dt o b e disproportionate t o th e potentia l benefit s resultin g fro

mareductio n i

n entrainmen

t croppin g an

dimpingemen

t losse s becaus e ofth e lo

w impact ofth e present

mod e of coolin g syste

moperation . Periodi c dredgin g ofth e intak e are ato reduc e approac h velocit y i s believe dto indirectly reduc e the impingemen

t rat e fo r fishes . N o reductio n i

n entrainmen

t o r impingemen

t of macroinvertebrate s i s expected . Becaus e sedimen t accumulate s i

n th e vicinit

y ofth e intakes , th e are ai s periodically dredge da s par t ofth e standar

doperatio n ofth e plant

andwill b e continue d afte r installatio n ofth e ne

w CC units . The modification s ofth e Unit s 1 throug h 5 intak e systemto serv e th e ne

w C C unit s will include adesig n improvemen

t t o enabl e hea

t treatin g th e entir

e lengt h ofth e intak

e conduit , rathe

r tha n jus t afraction as wa s th e cas e durin g previou s operatio n o f Unit s 1 through 5 . Thi s improvemen t wil l reduc e th e number s o f biofoulin g organism s linin g th e conduit s andtherefor e reduc e th e numbe r of entraine dfish an

dcra b larva e preye dupon b y thes e fouling organism s unde r th e previou s operatin g conditions . Alternativ e chemica

l biocides , applicatio n of

toxi c coatings , androutin e mechanica l cleanin g ar

e not considere dt

o b e effective alternativ e biofoulin g contro l techniques . 

### 7.4.2 Conclusions The propose dne

w combined-cycl e unit s CWI S desig n represent s th e bes t technolog y available . Thi s conclusio n i s base do n th e preliminar y finding o f

relativel y insignifican

t entrainment

an d impingemen

t effects andconsideratio n o f variou s demonstrate dalternativ e technologies , includin g potentia

l biologica

l effectivenes s fo

r furthe r reducin g entrainment

andimpingemen

t losses , engineerin g feasibility , andcost-effectiveness , a s outline din th e guidanc e manua l (EPA , 1977) . Intak e modification s associate dwit h th e combined-cycl e modernizatio n wil l improv e th e previously experience denvironmenta l impact s ofth e existin g intak e stmcture . Ne w shorelin e travelin g screen s wil l b e installe dto significantly reduc e th e entrapment (an dsubsequen

t impingement/entrainment) whic h formerl y occurre din th e 350-foot

intak e tunne l betwee n the intak e stmctur e an dpreviou s screen location . Additiona l modification s wil l allo w th e hea t treatment fo r biofouling/predator

organis mremova

l i n th e entir e coolin g water

supply conduit . Base d o n impingemen

t rate s reporte da

t th e neighborin g Unit s 6 and7 CWIS , thes e

E9-053. 9 7-3 9 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.9 5

7. 0 Evaluatio n o

f Alternativ

e Intak e Technologie s 

### controls . Reducin g coolin g wate r flow durin g extende dunit

outage s i s standar

doperatio n a

t th e plant an dwil l b e practice dfo

r th e ne w C C units . Th e estimate dincrementa l installe dcapita

l cos t of variabl e speedmotor s andcontrol s fo r Unit s 6 and7 , i

n additio n t o th e upgrade s alread y propose din th e project , i s abou t $ 4 million . Thi s cos t

i s considere dto b e disproportionat e t o th e potentia l benefit s resultin g fro

mareductio n i

n entrainmen

t croppin g an

dimpingemen

t losse s becaus e ofth e low impac t

ofth e present

mode o f coolin g systemoperation . Periodi c dredgin g ofth e intak e are at o reduc e approac h velocit

y i s believe dt

o indirectly reduc e th e impingemen

t rate fo r fishes . N o reductio n in entrainmen t o r impingemen

t of macroinvertebrate s i s expected . Becaus e sedimen t accumulate s i

n th e vicinit

y ofth e intakes , th e are ai s periodically dredge da s par t ofth e standar

doperatio n ofth e plant

andwil l b e continue d afte r installatio n ofth e new C C units . The modification s ofth e Unit s 1 throug h 5 intak e systemto serv e th e ne

w C C unit s will include adesig n improvemen

t t o enabl e hea

t treatin g th e entir

e lengt h ofth e intak

e conduit , rathe

r tha n jus t afraction a s wa s th e cas e durin g previou s operatio n of Unit s 1 throug h 5 . Thi s improvemen t will reduc e th e number s o f biofoulin g organism s linin g th e conduit s ah dtherefor e reduc e th e numbe r of entraine dfish an

dcra b larva e preye dupon b y thes e fouling organism s unde r th e previou s operatin g conditions . Alternativ e chemica

l biocides , applicatio n o f

toxi c coatings , androutin e mechanica l cleanin g ar

e no t considere dt

o b e effectiv e alternativ e biofoulin g contro l techniques . 

### 7.4.2 Conclusions The propose dne

w combined-cycl e unit s CWI S desig n represent s th e bes t technolog y available . Thi s conclusio n i s base do n th e preliminar y finding o f

relativel y insignifican

t entrainment

an d impingemen

t effect s andconsideratio n o f variou s demonstrate dalternativ e technologies , includin g potentia

l biologica

l effectivenes s fo

r furthe r reducin g entrainment

andimpingemen

t losses , engineerin g feasibility , andcost-effectiveness , a s outline di n th e guidanc e manua l (EPA , 1977) . Intak e modification s associate dwit h th e combined-cycl e modernizatio n wil l improv e th e previously experience denvironmenta l impact s ofth e existin g intak e stmcture . Ne w shorelin e travelin g screen s wil l b e installe dt o significantly reduc e the entrapment (an dsubsequen

t impingement/entrainment) which formerl y occurre din the 350-foot

intak e tunne l between th

e intak e stmcture andpreviou s screen location . Additiona l modification s wil l allo w th e hea t treatmen t fo r biofouling/predator

organis mremova

l i n th e entir e coolin g wate

r supply conduit . Base do n impingemen

t rate s reporte da

t th e neighborin g Unit s 6 and7 CWIS , thes e

E9-053. 9 7-3 9 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.9 6



## 8. 0 REFERENCE S Alde n Researc h Laboratorie s an d Ston e & Webste r Engineerin g Corporatio n (ARL/S&W) . Laborator y evaluatio n o f

fine-mesh screenin g for

fish larva e exclusio n a

t intakes . Researc h Repor t E P 8-6 , prepare dfo r

Empir e Stat e Electri c Energ y Res . Corp . 1980 . Alderdice , D.F . an dF.P.J . Velson . Som e effect s o f salinit y an d temperatur e o n earl y developmen t o f Pacifi c herrin g (Clupeapallasi). J . Fis h Res . Boar d Can . 28(10) : 1545-1562 . 1971 . Ally , J.R.R . A descriptio n ofth e laboratory-reare d larva e of Cancer gracilis Dana , 185 2 (Decapoda , Brachyura) . Crustacean a23:231-246 . 1975 . Ambrose , R.F . Foo dpreferences , pre y availabilit y an d die t o f Octopus bimaculatus Verrill . J . Exp . Mar . Biol . Ecol . 77:29-44 . 1984 . Anderson , W.R . an dR.F . Ford . Earl y development , growt h an d surviva l ofth e yello w crab Cancer anthonyi Rathbu n (Decapoda , Brachyura ) in th e laboratory . Aquacultur e 7:267-279 . 1976 . Applie dScienc e Associate s (ASA) . Ichthyoplankto n Monitorin g Stud y Deploymen t of aGunderboo m Syste ma t Lovet t Generatin g Statio n Uni t 3 , 1998 . Orang e an d Rocklan d Utilities , Inc . 1999 . Barlo w G . W . Intra

- an dinterspecifi c difference s in rat e o f oxyge n consumptio n in gobii d fishe s ofth e genu s Gillichthys. Biol . Bull . Mar . biol . Lab. , Wood s Hole . 121:220-229 . 1961 . Barlow , G . W . Specie s structur e ofth e gobii d fish Gillichthys mirabilis fromcoasta l slough s ofth e easter n Pacific . Pacifi c Science . 17:47-72 . 1963 . Barlow , G . W . an d V . D . D e Vlaming . Ovaria n cyclin g in longja w gobies , Gillichthys mirabilis, fromth e Salto n Sea . Californi aDepartmen t o f Fis h an d Game , Fis h Bull . 58(l):50-57 . Sacramento , CA . 1972 . Benech , S.V . Observation s ofth e southe mse aotte r Enhydra Lutris populatio n betwee n Poin t Bucho n an d Rattlesnak e Creek , San Lui s Obispo , California

- Januar y throug h Decembe r 1985 . In D . W . Behren s an dCO . White , eds . Environmenta l investigation s at Diabl o Canyon , 1985 . Pacifi c Ga s an d Flectri c Company , Sa n Ramon , California . 1986 . Bengeyfield , W . Evaluatio n ofa n Electrica l Fiel d t o Diver t Coh o Salmo n Smolt s fro mth e Penstoc k Intak e at Puntledg e Generatin g Station . Prepare d b y Globa l Fisherie s Consultant s Lt d for B.C . Hydro , Vancouver , B.C . 1990 . Bolin , R.L . A revie w ofth e myctophi d fishe s ofth e Pacifi c coas t ofth e Unite d State s an d o f lowe r Califomia . Stanfor dIchthyol . Bull . 1(4) : 89-156 . 1936 . Boreman , J . Impact s o f

Powe r Plan t Intak e Velocitie s o n Fish . U.S . Fis h an d Wildlif e Servic e Publicatio n FWS/OBS-76/20.1 . 1 1 pp . 1977 . Boreman , J. , CP . Goodyear , an d S.W . Christensen . A n Empirica l Transpor t Mode l fo r

Evaluatin g Entrainmen t

o f Aquati c Organis mb y Powe r Plants . Unite d State s Fis h an d Wildlif e Service . FWS/OBS-78/90 , An n Arbor , MI . 1978 . Boreman , J. , CP . Goodyear , an d S.W . Christensen . A n Empirica l Methodolog y for Estimatin g Entrainmen t

Losse s at

Powe r Plant s Site d o n Estuaries . Transaction s ofth e America n Fisher y Society . 110:253-260 . 1981 . Boulding , E.G . Crab-resistan t feature s o f

shell s o f burrowin g bivalves : decreasin g vulnerabilit y b y increasin g handlin g time . J . Exp . Mar . Biol . Ecol . 76:201-223 . 1984 .

E9-053. 9 8- 1 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0P.9 7
8. 0 Reference s Hewitt , R.D. , an

d G.D . Brewer . Nearshor

e productio n o

f young anchovy , CalCOF

I Rept . 24:235-244 . 1983 . Hochberg , F.G . Jr . an

d W.G . Fields . Cephalopoda : The Squid s an d Octopuses . Page s 429-444 in R.H . Morris , D.P . Abbott , an

d E.C . Haderlie , eds . Intertida l invertebrate s of

California . Stanfor

d Universit y Press , Stanford , Calif

. 1980 . Horst , T.J . The Assessmen t o f Impact Du e to Entrainmen

t o f Ichthyoplankto n i

n S.B . Sail a(ed. ) Fisherie s an

d Energy Production : A Symposium . Lexington Books , D.C . Healt h an d Company , Lexington , MA . pp . 107-118 . 1975 . Hourston , A.S . an

d C . W . Haegele . Herrin g o n Canada' s Pacific Coast . Can . Spec . Publ . Fish . Aquat . Sc i 48 . 1980 . Hsueh , Pan-Wen . Seasona l Occurrenc e an

d Abundanc e of

Brachyura

n Larva e i n aCoasta l Embaymen

t o f Centra l Califomia . Journa

l of Cmstacea n Biology . 11(4) : 546-552 . 1991 . Humann , P . Coasta

l Fis h Identification : Califomi at o Alaska . Ne

w World Publication s Inc. , Jacksonville , FL , U.S.A . pp . 176-177 . 1996 . Jacobson , L . D. , N.C.H . Lo , S.F . Herrick , Jr. , an d T . Bishop . Spawning biomas s ofth e northemanchov y i n 199 5 an d statu s ofth e coasta

l pelagi c fisher

y durin g 1994 . SWFC/NMFS . 5 0 pp . 1995 . Jacobson , L . D. , N.C.H . Lo , an d M . Yaremko . Statu s ofth e norther n anchov y (Engraulis mordax) stoc k (centra l population ) durin g th e 1996-199 7 season . SWFC/NMFS Admin . Rept . LJ-97-08 . 1 1 pp . 1997 . Jensen , G.C . Pacifi c coas t crab s an d shrimps . Se aChallengers , Monterey , California . 1995 . Jones , A.C . Th e biolog y ofth e euryhalin e fish Leptocottus armatus armatus Girar d (cottidae) . Univ . Calif . Pub l Zool . 67(4):321-367 . 1962 . Knudsen , F . R. , P . S . Enger , an d O . Sand . Awarenes s Reaction s an d Avoidanc e Response s t

o Soun d i n Juvenil e Atlanti c Salmon , Salmo salar L . Jouma l o f Fis h Biology . 40:523-534 . 1992 . Knudsen , F . R. , P . S . Enger , an d O . Sand . Avoidanc e Response s t o Low Frequenc y Sound i

n Downstrea

m Migratin g Atlanti c Salmon , Salmo salar L . Journa l o f Fish Biology . 45:227-233 . 1994 . Krebs , CJ . Ecologica

l Methodology . Harpe

r & Row , Ne

w York . 6 5 pp . 1989 . Krygier , E.E . an

d H.F . Horton . Distribution , reproductio n an d growt h o f Crangon nigricauda an

d Crangon franciscorum i

n Yaquinq Bay , Oregon . Northwes t Sci . 49(4):216-240 . 1975 . Kynard , B . and J . O'Leary . Behaviora l Guidanc e o f

Adul t America n Sha d Usin g Underwate

r A C Electrica l an d Acousti c Fields . Proceeding s ofth e Intemationa l Symposiumo

n Fishway s '90 . Octobe r 8-10 , Gifu , Japan , pp . 131-135 . 1990 . Lawler , Matusk

y & Skelly Engineer s (LMS) . 1996a . Effectivenes s Evaluatio n ofaFin e Mesh Barrie r Net Locate da t th e Coolin g Wate

r Intak e ofth e Bowline Poin

t Generatin g Station . Prepare d fo r Orang e andRocklan dUtilities , Inc . 1996 . Lawler , Matusk

y & Skelly Engineer s (LMS) . 1996b . Lovet t Generating Statio n Gunderboo mEvaluation Progra m1995 . Orang e an

d Rockland Utilities , Inc . LMSE-96/0291&169/330 . 1996 . Lawler , Matusk

y & Skell y Engineer s (LMS) . Lovet t Generating Statio n Gunderboo mEvaluatio n Progra m1996 . Orang e an

d Rockland Utilities , Inc . LMSE-97/019l&l69/321 . 1997 . Lawler , Matusk

y & Skelly Engineer s (LMS) . Lovet t Generating Statio n Gunderboo mEvaluatio n Progra m1998 . Orang e an

d Rockland Utilities , Inc . 169-335 . 1998 . E9-053. 9 8- 5 MLP P 316(b ) Resource Assessmen t 4-28-200 08. 0 References

Leet , W.S. , CM . Dewee s an d C.W . Haugen , eds . California' s livin g marin e resource s an d thei r utilization . Se aGran t

Extensio n Publication . UCSGEP-92-12 . 1992 . Lindquist , D.C . Th e Effect s o f Erosio n o n th e Trophi c Ecolog y o f Fishe s i n Elkho mSlough , CA . Unpublishe dMaster' s Thesis . Mos s Landin g Marin e Laboratories , Mos s Landing , CA . 6 5 pp . 1998 . Lo , N.C.H . Re-estimatio n o f thre e parameter s associate d with anchov y eg g an d larva l abundance : Temperatur e dependen t

hatchin g time ; yolk-sa c growth rate ; an d eg g an d larva l retentio n i n mes h nets . U.S . Dep t

o f Comm. , NOA A NMF S SWFC-31,38pp . 1983 . Lo , N.C.H . Eg g productio n ofth e centra l stoc k o f norther n anchov y 1951-1983 . Fish . Bull . 88:137-150 . 1985 . Lo , N.C.H . Modelin g life-stage-specifi c instantaneou s mortalit y rates , a n applicatio n t o northern anchovy , Engraulis mordax, egg s an d larvae . Fish . Bull . 84(2):395-407 . 1986 . Love , M . Probabl y mor e than yo u wan t t o kno w abou t

th e fishe s ofth e Pacifi c Coast . (2n d ed.) . Reall y Bi g Press , pp . 303-304 . Sant aBarbara , California . 1996 . Love , M.S. , G.E . McGowen , W . Westphal , R.J . Lavenberg , an d L . Martin . Aspect s ofth e lif e history an d fisher y ofth e whit e croaker , Genyonemus lineatus (Sciaenidae) , In Califomia . Fish . Bull. , U.S . 82:179-198 . 1984 . MacCall , A.D. , K.R . Parker , R . Leithiser , an d B . Jessee . Powe r Plan t Impac t Assessment : A Simpl e Fisher y Productio n Mode l Approach . Fisher y Bulletin . 81(3):613-619 . 1983 . Malzone , C Tida l Scou r an d it s Relatio n t o Erosio n an d Sedimen t Transpor t

i n Elkho mSlough . Master s Thesis . Sa

n Jos e Stat e University . CA . 1999 . Malzone , C , an d R . Kvitek . Tida l Scour , Erosion , an d Habita t Los s i n Elkho mSlough , CA . Report o f th e Elkho mSloug h Foundatio n t o th e Nationa l Oceani c an d Atmospheri c Administration . Awar d #NA370M0523 . 1994 . Matarese , A . C , A . W . Kendal l Jr. , D . M . Bloo d an d B . M . Vintner . Laborator y Guid e t o Earl y Lif e Histor y Stage s o f

Northeas t

Pacifi c Fishes . NOA A Technica l Repor t NMF S 80 , 65 2 pp . 1989 . McGowan , J.A . an d D.M . Brown . A Ne w Opening-Closin g Paire d Zooplankto n Net . Univ . Calif . Scripp s Inxt . Oceanogr . Ref

. 66-23 , pp . 1-56 . 1966 . Michaud , D . T . an d E . P . Taft . Recen t Evaluatio n o f

Physica l an d Behaviora l Barrier s for reducin g Fis h Entrainmen t

a t Hydroelectri c Project s i n th e Uppe r Midwest . Proceedin g ofth e EPRI/DO E Powe r Generatio n Impact s o n Aquati c Resource s Conference , Atlanta , G A (Apri l 1999) . 199 9 Miller , D . J . an d Lea , R . N . Guid e t o th e Coasta l Marin e Fishe s o f California . Califomi aDepartmen t o f Fis h an d Gam e Fis h Bulletin . 157:188 . Sacramento , CA . 1972 . Miller , D.J . an d J . Schmidtke . Repor t o n th e distributio n an d abundanc e o f Pacifi c herrin g (Clupea pallasi) alon g th e coas t

o f Centra l an d Souther n California . Californi aDepartmen t o f Fis h an d Game . 42(3) : 163-187 . 1956 . Morris , R.W . Earl y larva e o f four specie s o f

rockfish , Sebastodes . Calif. Fis h an d Game , vol . 42(2) : 149

- 153.1956 . Moser , H . G . Th e Early Stage s o f Fishe s i n th e Californi aCurren t Region . Californi aCooperativ e Oceani c Fisherie s Investigations , Atla s No . 33 ; 1214-1226 . Alle n Pres s Inc. , Lawrence , Kansas . 1996 .

E9-053. 9 8- 6 MLP P 316(b ) Resource Assessmen t 4-28-200 0P.9 9

8. 0 Reference s Moser , H.G. , an

dP.E . Smith . Larva

l Fish Assemblage s i

n the Californi aCurren

t Region an

d their Horizonta l andVertica

l Distributio n Acros s aFront . Bulleti n o f Marin e Science . 53(2):645-691 . 1993 . Moyle , P.B . Inlandfishes o f California . Universit

y o f Californi aPress , Berkeley . 40 5 pp . 1976 . Moyle , P.B . an

dCech . Fishes : A

n Introductio n t

o Ichthyology . Departmen

t of Wildlif e an d Fisherie s Biology , U. C Davis . Prentic e Hall , Englewoo d Cliffs , New Jersey , 07632 . pp . 46 , 121 , 304,305 , 426 . 1988 . Murdoch , W.W. , R.C . Fay , an dB.J . Mechalas . Fina

l Repor t ofth e Marin e Review Committe e t o the Californi aCoasta

l Commission , MR

C Doc . No . 89-02 , 34 6 pp . 1989 . Nelson , J . S . Fishe s ofth e world , thir d edition . Joh

n Wile y & Sons , Ne

w York . 60 0 pp . 1994 . Nybakken , J . W. , G . M . Cailliet an dW . W . Broenkow . Ecologi c an d hydrographi c studie s o f

Elkho m Slough , Mos s Landin g Harbor , an d near-shor

e coasta l waters , Jul y 1974 t

o Jun e 1976 . Mos s Landing Marine Laboratories , Mos s Landing , California . 1977 . Odenweller , D . B . The lif

e histor y ofth e shine

r surfperc h Cymatogaster

aggregata Gibbons, i

n Anahei m Bay , California . CDF

G Fis h Bull . 165 , Th e Marine Resource s o f AnaheimBay . p p 107-115 . 1975 . Orensanz , J.M . an

dV . F . Gallucci . Comparitiv e stud y o f postlarva l life-histor

y schedule s i

n fou r sympatri c specie s o f

Cancer (Decapoda : Brachyura : Cancridae) . Journa l o f Cmstacea n Biology , 8(2) : 187-220 . 1988 . Oxman , D.S . Seasona

l abundance , movements , an d foo d habit s o f

harbor seal s (Phoca vitulina richardsi) i n Elkho mSlough , California . MLM L Thesis . 1995 . Pacifi c Fis h Managemen

t Council (PFMC) . Sixt

h Amendmen

t t o the Norther

n Anchovy Fisher

y Managemen

t Plan . Portland , OR . 6 8 pp . 1990 . Pacific Fisher

y Managemen

t Council (PFMC) . Amendmen t 8 (t o th e Norther

n Anchovy Fisher

y Managemen

t Plan ) incorporatin g anam e chang e to : The Coasta

l Pelagi c Specie s Fisher

y Managemen

t Plan . Portland , Oregon . 1998 . Pacifi c Ga s uzd

Electri c Compan

y (PG&E) . A

n evaluatio n ofth e effec

t o f coolin g water

discharge s o

n the beneficia

l use s o f receivin g water s a

t Mos s Landin g Powe

r Plant . Mimeo . PGandE , Sa n Francisco . 1973 . Pacifi c Ga s an

dElectri c Compan

y (PG&E) . Mos s Landin g Powe r Plan t Unit s 1- 5 316(a) demonstration . PGandE , Sa

n Francisco . 1978 . Pacifi c Ga s an

dElectri c Compan

y (PGandE) . Potrer

o Powe r Plan t coolin g wate

r intak e structur e 316(b ) demonstration . Prepare db y Ecologica l Analysts , Inc . PGandE , Sa n Francisco . 1980 . Pacifi c Ga s an

dElectri c Compan

y (PG&E) . Impingemen

t Studie s a t Morr o Ba y Powe r Plant . PG&E , Departmen

t o f Engineerin g Research , Sa

n Ramon , CA . 1982 . Pacifi c Ga s an

dElectri c Compan

y (PG&E) . Mos s Landin g Powe r Plan t Coolin g Wate

r Intak e Structure s 316(b ) Demonstration . PG&E , Sa n Francisco , CA . 1983 . Pacifi c State s Marine Fisherie s Commission , (PSMFC ) 1999 . http://www.psmfc.org / habitat/edu_herring_fact.htm l Pacifi c State s Marine Fisherie s Commission , (PSMFC ) 1999 . http://www.psmfc.org/Lifehistory/crab_fact.htm l

E9-053. 9 8- 7 MLP P 316(b ) Resourc e Assessmen t 4-28-200 0