ML19007A335

Map of Conowingo Pond Showing Location of Stations in Trawl Zones 405, 406 and 408 - Figures

ML19007A335
Person / Time
Site:	Peach Bottom
Issue date:	01/07/2019
From:	Exelon Generation Co, Philadelphia Electric Co
To:	Office of Nuclear Reactor Regulation
Shared Package
ML19008A020	List: ML19007A326 ML19007A327 ML19007A328 ML19007A330 ML19007A331 ML19007A334 ML19007A335 ML19007A340
References
Download: ML19007A335 (123)

Text

\

xone '~ :i 401 ~ 402 a************

• j J \l.

1 l

I I

I zone

• tone 1

1 j

403 I: 404

• l/'J ama*l***~ T. JOHNSON PEACH BOTTOM ATOMIC POWER STATION '/, 456 ,*

1 l.

'l/ 4~5* l 406. -;;,**~

455

• 466 453 454  ! 464 f '!..

STONEWALL POINT '/1452 I 46211461 451*****.§.******wh:...PETERS CREEK I ~!

• ' 486 )

r~

11495 ICHTHYOLOGICAL ASSOCIATE.

zone .. zone 48(/4'~483 FIELD STATION 407 *' 4Q8' J'i //J :~~i~M I

r"' I

• 482_,0

/~4a1 BEACH MICHAEL RUN STATE LINE '\,PA.

MD.*  !

111*****tl***** WILLIAMS TUNNEL

• zone

.. ' *,~l

~

zone l '*

409 l

• PA.

' *._ _ _ _ BROAD CREEK_ _ _ *---~l__ ~ M~ --- -----

~. l \FRAZER TUNNEL *----

~ - *****,/,..

.... WILDCAT TUNNEL

{*

\

i

' Map of Conowingo Pond show! . ~

).* location of Stations in Trawl_ ,

FIGURE 7.2.1-2 Zones 405, 406 and 408, 0

I I I I SCALE IN MILES 7.2-14

MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE POND FISHING CREEK MUDDY CREEK PEACH BOTTOM ATOMIC POWER CREEK STATION PEACH BOTTOM BEACH 333 371 WILLIAMS TUNNEL 332*---

331 STATE LINE PA. MICHAEL RUN MD. FRAZER TUNNEL 343 WILDCAT TUNNEL 0 z 3 SCALE IN MILES FIGURE 7.2.1-3 Hap of ConoVl'ingo Pond showing the location of Stations on Trawl Trans~cts 1-4, and 7 (dashed Lines).

7.2-15

MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE PONO

\

I'

' .!f MUDDY CREEK

_........_ ___'-:*,.,.**1

.i

'\. *:!

PEACH BOTTOM ."j ATOMIC POWER CREEK STATION STONEWALL POINT PEACH BOTTOM BEACH WILLIAMS TUNNEL

• ~

STATE LINE-P_A_ . -----

MO.

WILDCAT TUNNEL 0 2 SCAl.E IN Mil.ES FIGURE 7. 2. 1-4 l-1ap of Conowingo Pond showing the location of Seine Stations.

7.2-16

\.

MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE POND FISHING CREEK MUDDY CREEK

....____,.__561 ROLLINS POINT ~ MT. JOHNSON I.

570 ' 575 560 PEACH BOTTOM * . ~ 576 ATOMIC POWEF~ ~{, CREEK STATION 562 '*

563 STONEWALL POINT PEACH BOTTOM 8EACH 564 WILLIAMS TUNNEL 565 567---.ltV 569 568-4-'

STATE LINE _P_A._ _ _,,_,;...--..;;

MD.

0 2 3 SCALE IN MILES FIGURE 7. 2 .1-5 Map of Conowingo Pond showing the location of plankton net Stations on Transects 1, 2, 7 and 8 (dashed lines).

7,2-17

..~'

i II._

7.2.3 FISHES IN THE THERMAL PLUME 7.2.3.1 Trap Net Catches Intensive trap netting was conducted in the thermal plume and discharge canal of PBAPS in July 1974 through March 1975. Each of s~ven stations (Figure 7.2.3-1) were sampled twice a month. The studies are continuing. Full power operation of both generating units did not occur until late in December and the power level fluctuated considerably in the sampling period.

The bottom water temperatures recorded at each of the ahove seven stations and at the regular Pond monitoring stations are given in Table 7.2.3-1. A delta T of up to 14 F was observed at the stations in the thermal plume.

some 29 species were caught in the plume and

• were taken in the discharge canal, and 37 at monitoring stations (Table 7.2.3-2). The common fishes in the plume were the white , .

crappie~, channel catfish, gizzard shad, carp and bluegill. In the discharge canal they were the pumpkinseed, channel catfish, bluegill and white crappie. At monitoring stations the common fishes were the white crappier bluegill, channel catfish, pumpkinseed and brown bullhead. The white crappie avoided the canal. In contrast, the channel catfish appeared to prefer the canal in some months. The gizzard shad was taken primarily in the plume. No consistent pattern of distribution was evident for the bluegill. Few smallmouth bassr largemouth bass and walleye were collected.

The 20 species caught in the canal were subjected to the highest delta T, highest water velocities and greatest fluctuations in temperature during the operation, shutdown and start-up PBAPS. No fish mortalities were observed in the discharge canal or plwne after a station shutdown or start-up.

Fishes were present but scarce in the canal throughout the study period. Fishes did not avoid the plume.

A comparison was made of the trap net catch of the common fishes collected near Burkins Run (Station 110), about 300 yards below the discharge canal and in the discharge canal in the preoperational (1967-1973) and postoperational (1974-1975) periods (Table 7.2.3-3). The white crappie was abundant in the

- - - * - - - canal in - preoperational yearS- but -in- 1974 the catches of white~-

crappie and bluegill had declined. However, the abundance of channel catfish increased considerably in the canal compared with preoperational years. At Station 110 the postoperational catches of the common fishes were generally within the range of variation observed in the preoperational period (Table 7.2.3-4). How~ver, here the catch of channel catfish in the postoperational period were higher than in 1970-1973.

7.2-19

7.2.3.2 Trawl Catches Trawling was done to determine the distribution and abundance of fishes in the discharge of PBAPS from July through December. These studies are continuing. A control st~tion (Station 453) was established upstream from the discharge (Figure 7.2.3-2). Temperature at this station was used as a reference for ambient conditions in determining the discharge delta T. The bottom water temperatures along the trawl track at Stations 450, 451, 470 and 473 were generally more than 1 F higher than those at the station intake (Table 7.2.3-5) and these stations were considered to be in the thermal plume. Water velocity at station 450 and 451 was high as a result of the jet discharge; it was less at Station 470 and 473, which are located downstream and near shore. Stations 452, 472 and 474 were located on the periphery of the plume and the delta T at the bottom was usually less than 1-F.

Thirty-one species were captured in the plume, 25 were taken at the periphery and 23 were found at the control (Table 7.2.3-6). More species were collect~d in the plume where there was an increase in temperature compared with stations where there was increased temperature and flow. The largest number of fishes (27) was caught at Station 470 and the least (15) at Station 471.

The common fishes were channel catfish, tessellated darter, white

.1 crappie, bluegill, carp, spottail shiner, and pumpkinseed.

channel catfish, tessellated darter and white crappie comprised 98% of the total catch at the periphery, 94% in the plume and 86%

at the control. The catch per effort in the plume was twice as The

.* great as that at the periphery and five times greater than at the control. In the plume, the total catch per effort was higher in i*

f. the area affected only by an increased temperature, particularly

~ . at station 470, than it was in the area affected by both increased temperature and flow.

l

• The abundance of the common fishes differed between months in the three areas. Usually the largest catch of all species was at station 470 which had the highest delta T and little velocity. The catch per effort of the channel catfish increased sharply in all areas from July through September. The large catch in September in the plume was due to some 25,000 channel catfish (mostly young) which were collected in one trawl haul at Station 470. Thereafter, the catches generally declined in all areas. An increase in the catch of channel catfish occurred in the plume in December. In October and November the catch of the channel catfish was greater at the periphery than in the plume or at the control station.

In all areas the abundance of the white crappie differed little from July to December. Generally, the lowest catch occurred in the plume area which had both increased flow and

1. 2-20

~ .. ,., ....

temperature. The catch was greatest in the plume in all months except in October and Novemb~r when it was higher at the control station. In most months the abundance of the t:essellated darter was greatest at the control station and at the periphery of the plume. The catch per effort of the bluegill and pumpkinseed was highest in the plume, particularly at Station 470, from July through November. The bluegill was common in the plume in December but the pumpkinseed was not taken. Relatively large numbers of both species were taken in the plume in August and September. The spottail shiner was most abundant in the plume except in December. A few gizzard shad were caught at most stations but it was taken consistently only at station 470 in the plume in all months. It was never caught at the control station.

7.2-21

TA!ll.~~ 7,?,)-1 Coc;>3r\:1001 of the :aanth.1y mean bottom w4tiar ce.r.tjH::~aturt. at Tt'ap ?Jet StAtton.r in and outd.da tbe chema\ plumo. in. Canowingo Palld , July-O'IJ.\!vr:!hn' l'H'**

DISCILIJCE UPP~ .l..~O KTD PCl~:O CA,fAL TllERMA L PLL'ME LO'.n:R ro:m Station m m m !1+z rm; l[i7~ 122 123 ll4 llO 12j 126 127 107 ll6 103 138 109

~*.a nth ~at.toa

'i~.:;a (F)

Jul ~J.n. 78.0 67,0 77.0 77 . 0 76.0 77.0 70.0 85.0 85. 0 78.0 78. 5 74.S 79.0 79.0 79.0 l'..u:. 80,5 75.D 80.0 80,0 81.0 81.0 89.0 88 . 0 88.0 88.1) 81.0 80.5 82.0 83 . 0 81.5 Xea11 78,9 11.0 78 . 4 78,S 77.6 79. 2 76.2 86. 8 86.6 83.2 79 . 5 77.8 80.Z 80. 4 80.l Aug: :0-J.n. 77 . 0 69.5 76.S 78. o 75.S 78.0 85.0 84.5 84.5 83.0 8z. 5 81. 0 82,5 78.5 76.0 79.0 74 . 0 78.0

!'...ix. 79.0 n.5 79.0 so.o 79.0 80.0 88 . 5 88.5 88.5 85.S 87.0 83.5 83.0 81.0 78.S 80.0 80.0 80.S Me3a. 78, l 70.2 78.1 79,0 77,3 78,S 86,6 86.l 86.0 84.1 84,8 8z.1, 82,8 79,5 77.0 79,6 73.6 7?.4 Sep Mln. 71.0 62.0 70.' 7l.O 69.5 71,S 70,0 70.0 70,0 7],0 69.5 68.0 6?,0 70.S 6~.o n.o 71.5 H.5

~..i.-i. 79.0 69.5 79.0 79.0 79.0 79.1) 80.0 79.5 79.S 94. 5 7S.O 72.0 73,0 80, 0 n.o 8~ . 5 s~.o eo. s

~!cAD 74.4 64.6 73. 7 74.2 n,8 74. l 1S.O 74.8 74.S n.o 73,J 69.6 70. 2 74.4 12.s 75.6 7S,2 75.1 Oct Hlu. 52.5 45. 0 lJ.O 54.0 '5.0 53.u sa.o 5G . O 56.0 62.5 55. o 55 . 0 54.0 57.0 52.0 55. 5 53. S 55 . 5

!A<t . 65,0 60.5 64.0 63.0 65,0 63. S 70 , S 70.0 69, 5 72.0 6').0 GS,O 62.0 67,5 65 ; 5 67 .o 67 . 5 68.0

~C4tl 5a.e 54 . 0 59.~ 59.2 60,5 58. l 64,8 64.3 64 . l 66 . 4 6J.1 6(), \ '1 . 7 61 , 8 58 . 5 61. 4 60.8 6l.6

~:ov mn. 42.0 35.0 40,0 40.0 38.0 39.0 56.o 56.0 56.0 ,1.0 54,0 50.0 47 .5 42. 0 40.0 39.5 l'!,5 41. 5 MAx. 55.0 47.0 55.0 ss.o 54, 0 ss.o 66.0 66,0 66. 0 65.0 64.0 59. 0 60.0 55,5 52.0 56.0 5:5 .o 55 .5

!'.i!llD so.o 42.8 49.8 49.8 48.6 49.6 61.4 61.8 61.8 60.3 61).1 53.l 53.8 51,2 47.9 H,0 5<), l 50.S D<!c l'.111. 36.0 36.0 36.0 36. 5 36.5 37.0 4S . O 52.0 5?.0 ~4.5 51.0 48.5 43.0 38.5 39.5 37 .5 37.0 38.0

~..:i.."t. 39,0 113.0 40.0 40.0 39.0 39 . S 52.0 54.0 53.5 o.o 52.5 52.5 47.0 42.0 46.0 110.0 41.0 H.O Het.:l 37 *'

n.o 37.8 37.9 37,8 38. L 50.2 53.1 52. 3 46.4 SL.a 50. J 44.a 40.l 41.9 38.5 3~.a l?.O 7.2-23

-~

TA!iL~ 7.2.3-2 fr, l',.

Comparison of catch per effort (number per 2~ hr) for fishes collected by trap net at the monitoring stations, discharge canal, and plume stations in Conowia~o Pond, July 1974-March 1975.

Locations Monitoring Stations Discharge Canal Pll.lllle Stations No. Collections 339 109 120 No. Species 37 20 29 No. Hours 9148 2659 2971 No. Trap Days 381.17 110.79 123.79 - ....... -

Species A* calva A* rostrata

• 0.01 0,01 0 06

!!.* cepedianum 0,09 0.15 ~

~* ~

• 0.01

!* masguinong! 0.01

£. auratus

• 0.01 0.01

c. carpio 0.29 o. 10 ~

!{. crysoleucas 0.23 0.02 0.23 M*  !!!!~ 0.03 0.01 M* cornutus 0.01 l'i* hudsonius 0.38 0.01 0.17

!* procne 0.02

!* S(!iloeterus 0,06 0,02. 0,02.

E_, notatus 0.01

£. cyprinus 0.01 0,02 Q. commersoni 0.12 0.01 J!. nigricans *

!!* 111aerolc12idotlD11 0.01 0,03

!* catus 0.05 0.04 0.17

1. natalis 0.46 0.45 1.51

!. nebulosus 0.99 0.39 1.90 1* punctatus

.t!* insignis ~ ~ ~

M. americana 0.01 A* rupestris auritus 0.15 0.32.

0,11 0.12

~* 0.44 0.06

~* cyanellus 0 02 o.os 0.01

~ ~-

F-~ gtbbosus 1. -

~* macrochirus 2.04

!:!* dolomieui 0.03 0.01 0.01 H* salmoides l,. annularis ~ 9 0.49

~

!* nigromaculatus 0.17 0,36

!* olmstedi 0,01 0.01 0,02

!* flavescens 0,06 0,06

!* caprodes .,,*

!* vitreum 0.02 0,02

~

Total 39,43 16.82 55.57 teas than 0.01

• 7.2-24

• \r** . .,

~~..

• ~?

• ~**

~~,. ~

? .*

TAl'LE 7,2.J-3 Cmparhon of th4 catch !'Of effort (numbe\' pn 24 hr) of 1&lacted npnHotatlw todt11enoua flohaa colle.:ted f~ the diacharge caaal during cha preoperat1ol\4l (196~*19ll) a.id po*top<aracional (1974) pertod* 11> Coaovinao l'ond, . .,* .

Jul-Dec Total

\lhlta crappie Q. annula'l'l*)

(* 1967 n.46 1968 .

• 93.46 1968 27.39 1969 52,96 ' 31.0S 1969 228.49 1970 60.71

.;, . 207.19 1970 102.'1 197l 1971 131,96 1972 2os.u " * *"*... "*:m.84 102.91 mi 37.10 1973. ".37.10 ..*.j

• , ! 1973. 1974 197.0 0.68 1975 o.u . 0.49 Q111md cacfhb (!. pt111ctatus) 1967 10,36 1968 1968

" 10.36 "

1,29 1969 1.54 1969 1970 12.83 1%,06 1970 1971 o.s1  : . . o: 1t~~ * *

. :*""":':' 11.06 \ .

1971 s.43 1972 3.52 ...:*.,.

• 4.aa* ..*

1972 1.84 1973. . ... ; .'. .1.84 1973* 1974 1974 1975 2,Sl *"?.:-'* 5:9,- ".

Jlluegl 11 ~* 1114crocht rus) 1967 2,03 1%8 1968 1969 10.4.S 9.20 1969 1970

' .;*/*. ~:=.

8.42 :*

1'70 19.0l 1971 .. : U,Ol".

1971 36,16 1972 9, 38 . 28.48 *"

1972 9,47 1973* 9*47 "

1973 .. 1914 1974 3,43 1'375 0,87 2.53 ;.*:

Ci&&*rd *had ~. cepedl*n*"")

1972 0,64 1973* 0.64 1973* 1974 1974 0,07 1975 0,31 0,15 Large-.th ban (!!. 1almoldu) 1967 o.oo 1968 o.oo .

1968 o.oo 1969 o.oo o.oo.

1969 o.oo l970 0.00* o.oo 1970 o.oo 1971 o.oo 1971 o.oo 1972 0,00 o.oo 1972 o.oo 1973* 0,00 1973* 1971, 1974 o.oo 197S o.oo 0.00 Slllall.oiouth baaa <!:!* dolomteut) 1967 o.oo 1968 o,oo 1968 0,04 1969 o.oo 0,04 1969 o.oo 1970 o.oo o.oo 1970 o.oo 1971 o.oo 1971 o.oo 1972 o.oo o.oo 1972 o.oo 1973* 0,00 1973* 1'74 1974 0.01 197S o.oo 0.01 1967 .o.oo 1968 o.oo 1968 o.oo 1969 o.oo o.oo 1969 o.oo 1970 o.oo o.oo 1970 o.oo 1971 o.oo 1971 o.oo 1972 o.oo o.oo 1972 1973*

o.°' 1973*

1974 0,09 1'74 0,03 1975 o.oo 0,02

• Wot tanipled c!11e to coattructlOCI 1.2-25

l'*

h.

i 1:

,i

1:.

TABLE 7.2.J-4 j;

! ComparlsoG of the catch per effort (n\llllber per 24 hr) of 1elected representative indigenous fishes collected at Station 110 during the preoperational (1970-1973) and po1toperation.1l (1974) periods in Coo.ovingo Pond.

I, i Jul-Dec J&11-Har Total

~ t *

'i*

White crappie (!. annularis) i ~* .*

I 1970 90,29 1971 90.29

• ~

., 1971 38.24 1972 u.11 29.70

: . 1972 37.93 1973 6.74 31.07

.... 1973 7.19 1974 1.38 6.06 1974 s.18 1975 0.78 4.13 i :. Ch&DAel catfish (!. 2=ctatus)

\'i\. 1970 1971 24,61 7.17 1971 1972 24,61 7.59

~.r

- - . - 8.45 1972 2.24 1973 10.71 4.10 it.:

~4.

1973 1974 1,27 17.97 1974 1975 0.78 1.17 1.18 U.97

~-- llluagill C!:* 11>acroch!.l'Us) t**'

tl

.. 1970 3,14 197\ 3.14 j':L 1971 1,85 1972 0,25 1,33 1972 3.65 1973 0.17 2.89

~t 1973 1.46 1974 o.39 1.25 f"

~it . 1974 1.74 1975 0.13 1.36 r~.= Gizzard 1had (~. cepedian1.111S) iii.- 1972 1973 o.oo o.ot.

1973 1974 o.oo o.oo o.oo 0,04 r 1974 r*T l

3.36 1975 0.39 2.65 Largamouch bass Q!. sa biol.des)

'l 1970 t"': 1971 o,oo o.oo 1971 1972 0,00 o.oo o.oo 11F*

~t,'*

1972 1973 0.10 0.09 1973 1974 o.oo o.oo 0.08 o.oa r1**. 1974 o.oo 1975 o.oo o.oo

~:J: *.':. Smallmouth baas @* dolomieui) f.JLi 1970 o.oo 1971 o.oo r*l':*

~:

1971 1972 1973 1974 o.oo o.oo o.oo o.oo 1972 1973 1974 1975 o.oo 0,00 o.oo o.oo o.oo o.oo o.oo

(.,

~ ,.

~:~:*. Valleye (!!,. ~)

o.oo

~t. 1970 o.oo 1971 o.oo

~~~*:

1971 o.oo 1972 o.oo o.oo 1972 0.15 1973 0,86 0.30 1973 o.oo 1974 o.oo o.oo i~f* 1974 o.04 1975 o.oo 0,03

...~; ----

li'}"

~~*;;:.

~:i~..

r~:~.'\

{

ti I:,

• r If 7.2-26

.:,::;~::.-:

.. {.:~::

. ~: ..

1\.-:>t:t"\ll W:\tl:t' cc:mpera.rure, l:!i. T, perccntilge power af l'nlts ~:a. 2 ond J, d~1il:-i fl,.*e~ flew (n\t:a.sui*cd ot Holt1'lood ll~o) at stlltions in ,ind o...itslde the thc~l plt.Une uf tho l'ciach ~ttom .\tl)tl{c i'ovcr Stilti.rJn, Conor.rln!*,I) !"ond, *-0<1k o! 7 July .. vol?.k of ~2 l'ecembnr 1974.

Stntiun fcrnp (F) t*:cek o[~

Jul 7 6\.8 2.6-l.? 84.6 S.7 4.4*6.3 8?.2 J.J L.4*3. 7 80, l 1.2 0.0.1.a 80,5 1.6 o. 7 14 M4. L 3,9.1,,4 85.9 6.l 5.7*6.? 84.6 4.9 4.4*5. l S0.9 I.~ 0.6-1.7 81.0 1.l 1.0°1.I, 22 78 .8 0,6*0, 7 SQ, 3  ?.I 0,9*3,? 79.6 1.4 0.3*1,9 78,S 0,J 0.0-0.1 76.l 0.1 0,IJ*O, 2 29 aJ.o 3,8*5.l SS. I 6.a 5.<*o.~ 51., 7 5.6 4.3*&.9 79. 6 0.5 *0.1-1.2 79 .5 Q,I, *0,)*1.2 QVCt'llll :-teAn

£Ln<1 Range 81.) ],) 0,6*5.I 8J.1 4.1 0,8*6.? so.o 1.0 *0,l*l.8 80, I 1.1 *0,3*1.4 1, Sl.C 3.1 l.?*5,? 85,3 '.~ 4.1*8.9 83.0 J.1 J.0-J,2 80.2 O. l *0.2*0,6 80.0 0,l *O.l*O,lt lt 81.l 3. s l.1*4.~ B4.I 6.J 5.9-7,0 81.9 4.1 3.0-5. J 78.6 0,9 0.3* l.4 7!1.l 0.) *ll. l*0.7 LB 82, 2 3. l 1.9*3,9 83.! 4,8 ),9*5,8 83.J 4 *) 4,0-4.5 eo. 1 1.6 1.0*2.9 79. 3 0.2 *0.5*0,')

25 82.0 2.0 1.1*2.7 86.1 b.l l.l*9.2 8'*.6 4,6 J.8*5.9 80,'.I 0.9 0.?-1.4 81.1 l. l 0.4*2.0 nvcr.3tl ~~rm 8?, l 2.8 1,1*5.2 85.0 5.7 l.1*9.2 81.4 1,,1 J.0*5.9 &0,2 (1.9 *D.2*2.9 79.9 1).6 *0.5*2.0

~h!p l 76. l 0.7 <),l*l.l 81,6 6.2 4.7-7.5 79.S 4.4 3.6*1,,9 17 ,I) 1,6 1.1*2. I 77.? l.8 1.5* 2.5 11 6~.5 n.~ o.s-o.a 1a.1  ?.2 8.8*~.5 73.5 4.6 3,9*5.5 b9.2 0. 1 0.0-0.5 ~9. 2 0.3 O.l*O. o IS 72.? 0. 2 0, l-0. J 76.D 4.'l l. l*S.5 1:..6  ?.6 l.l*l.7 72.5 o.s 0.1-0. 7 72. I 0.1 *0.3*0.S 22 69.5 0.8 o. ]*Q,j 7l.~ 2. 7 0,6*5. L 71.0 2,) 1.6*4,<J 6~.7 1.0 o.q.1.0 M.l 0.4 -0.ft*l,0 Overall ~!t!an und Mr.go 71.8 0.5 0.1-1.1 77.0 5.1 o.6-9,5 71,,a o.8 o.o.i. 1 11.*l 0.6 *0.4*2.5 Sep 29 63.6 l.1 0.7*1.5 67.:. 4.~ '**5*5.? 6~.2  ?. 7 2.6*2,9 62. 7 ),? -0,)-0,9 6.?.9 o,:, *0.6* l.S Uct ~ 60.3 l. 7 Q,6*2.7 67.6 ~.5 1,6*'1.1 64.4 5.3 4.1*5.6 5'1. 7 0.6 ll.0*1. J 60.5 I.It 0.7*2.lt 13 62. l 2.l 1.!t<!. 1) 65.7 5.~ l.4*1U.5 6.J.3 J,5 l. 6-6. 3 60.6 O.d Q,t,-1,4 60,8 1.0 G.ft* l, S

~) 56.0 1.9 1.6*2.2 5j.l 5.o z.~*~.2 58,? 4, l 2. 2*7 .4 55.1 1.0 0.2-1.6 5S. l 1.2 l.ll* 1.'*

Cl"veT'Gil 1 Mea.n.

und ~.tinge 1.9 1),6*2.9 64.7 6.?  ?.6*10,5 62.6 4.1 1.6-6.3 59.2 o. 7 -0.5*1,6 S9.6 l.l *0,6*2.4 Nov 3 58.4 2,3 0.8*3.6 61.9 5.8 5.1-7.4 61.2 j, l 4, 7., ,5 57. 5 1.11 0,5*?.2 57 .s l,.'f. 1.0*1.8 10 59. 5 5.4 ],l,-9.1 64,0 *),*) 7.1*11.6 6l.9 7.6 6.\1*9.a SS. 7 1. 6 \,4-2. 0 56,0 l.*l 1.7*2.J 17 1,9,1 4.8 2.?*7.J 56.4 12.1  ?,J*l],lt 54,6 10.3 e.o-u. 2 47.9 J, 6 0,6*7 .1 47. J J,0 2,7*).2

?4 43,.; J. 7 0.9*5, l 5l.1 ll. l  ?.7*14.2 50.0 10.1 9.4* lG.2  !.'l. 1 3. 2 1.9-J. 9 45. s 5,oj 5. 2*5.11 fiVC\'3l l Me.in er.d !lrat\ijC sr*. o 4,2 o.~*9.o 59.4 ~.6 5.1-14,2 57.5 7.7 4.7-11.2 51.l~ 1.9 0,5.7,1 52.1 2.J 1,0*5, 2 Doc 1 43.5 6.2 J. 5*9.8 44.8 7.5 4.J-12.4 45,0 7. 7 4,7-12.1 42. 5 s. 2 1.9*9. l 41.5 4.2 2.1*6. I

~ I,], 3 5.6 4.9*5.9 46.l 8.4 ~.1** 10.1 43.0 5. J 4.2-6.5 40,3 2.6 2.2*),0 J~.4 1. 7 1.0-J, J 15 44.5 6.4 J, 9*!1.4 50.4 12.3 L0,4*13.? 48,7 10, 6 9.9*11.S 1.2.s ~.1. 3.0*6.5 42.1 ~.o 3. t-t.. 6 22 44.1 7,8 6.)*~.2 49.u l~.7 ll.7*1J.S 48,? 11,9 11.2012,8 l1J, 7 7.4 6.6*8.4 4 1J,O 3. 7 l.4-4.0 Ovcral 1 ~a:an oml Jlar,lJe 43.9 6.5 J,9*9.9 47.6 L0.2 4.J*lJ,8 46.4 *J,0 4.2-12.8 42.J 3.6 l.0*6.1 cont{nu.ed 7.2-27

'i

• ...~*.

'l'~flL& 7.?.J-5 continued, r ~ R 1 l' 11 R y CO~"rROl Statioa ill 472 474 453 Tc11111 At Ta01p Mean A Tknngo Telll\> 0, T Ter;ip rercnntago Daily River O'l Hean Rnngo (F) (F) }ie4n Ranga (F) Po\.IO:r YlDw (lo3x c fa) week of:

Jul 7 78 .4 -0.5 -o.4-o. 2 78.3 *0,6 -0.3-0. 0 78,9 100 21.5*32.5 14 80.0 0.3 0,0*0,6 80.l 0.4 o.o-o. 5 80.3 0,6 O. l*0.9 79. 7 100 14.3*15.5 21 78.3 O.l -0.1-0.1 77 .8 *0.4 -0.6* 78.0 -0.1 -0.4-0.0 78.2 0* 100 8.9-l0.6 18 73.9 -0. 2 -o. 7*0 . 3 79.4 0.3 0.1-0 ,4 79,6 0.5 o.3-0 . 1 79. l 96-100 u. 3-12.6 Overall ~:enn 0,0 0,2 -0,6-0.S 79,7 o. 7 o.o-o,9 79.0 0-100 e.9-n,5

_ And Raage 79 . 0 0 ,4

~

• O. 7*0,6 0 , 0-IJ.9 79.2 79 . 8 *O. l *0.6*0. 3 79.7 -0.2 *0,5*0, L 79.9 85-100 l2.0-2l,9

,\ug 4 80.3 l\ 78.1 0.3 0,2*0,4 17.8 0,0 -0. l*O. l 78.2 0.4 o.o-o.8 77.8 100 8. 7-10,4 18 79.5 0.4 0.1*0.8 79.4 0,3 o. 2-0. 7 79.9 o.8 0 . 1-1. 7 79. l 100 7,3.7 .9 25 80.2 0.2 *ll. 3-0.5 80.4 0.4 o.o-o. 7 80,6 0.6 0.1-0.8 SfJ.O 80-100 6, l-21.9 ove tal 1 nann and Ra11ge 79.6 0.3 -0.3-0.9 79.5 0.2 *0.6*0.7 79. 7 0.4 -o.5-1. 1 79. 3 80* 100 6.1-21.9 Sep l 75,8 0.4 0,2.*0.6 76. 3 0.9 0,6*1.9 76. 7 1. 3 o. 7-2. 2 75,11 102-120 24.4*45,0 8 69.0 o.o-o. l 69,0 0.1 *0.1*0.3 68.9 o.o -0. 2-0, 3 68.9 120*122 1a. 6-za.1 15 71.9 -0 . 1 -0.2- 0.0 7L . 8 ..0.2 -0,5.0,1 71.8 -0.2 -0.4*0.l 72.0 31-80 14 . 0-18.1 22 68,8 O. l -0.1-0. 2 68. 9 0.2 -o. s-o . 7 6~.o 0,3 *0, 7- 1,3 o8. 7 0-81 14.6*20.4 Overall Mean and Rang* 71,4 0.1 *O. 2*0,6 11.s 0.2 -o.s-1 . s 71.6 0.3 -o. 7-2.2 71.3 0-122 14.0-45.0 Sep 29 62,4 -0.1 -o.s-0.2 &2.6 O, l -0,4-o. s 62. 7 0,2 -0,7-l.l 62.5 84-86 16. 7-17.9 Oct 6 59,2 0.1 -o. 3-0,3 59,4 o. 3 -0.1-0.~ 59.5 0,4 0.1-0. 7 59.1 109-149 12 .4-14. 2 13 59.9 0.1 *O, 3*0.4 60.2 0.4 *0.3*0 , 9 60.4 0.6 *0, l-0,9 59.8 57* 151 9.0*12.4 ...........

20 54.1 o.o *0, l*0,4 54.1 0,0 -o.8-o.4 5S,O 0.9 0.5*1.4 54. l 67* 132 l0.3-11, 1 273 Overall }:ecin 1md R.e.nge 58.6 0.1 -o. 5-0. 4 58.7 0.2 -o.8-o. 9 59 , 1 0.6 -o. 7* 1.4 58.5 67*157 9,0*17.9 Nov 3 56.2 0.1 o.o-o.l 56,4 0.3 *0.3*0,7 57.l LO -0.1-1.9 56,L 56-67 8,0-8,4 10 54.l o.u 0.0-0.1 31,,2 O, l *0.3*0, 5 54.6 o.s 0.4-0,9 54,1 115*175 19.3*20.3 17 44,5 0.2 0.4-0.1. 44.9 o.6 o. 3*0.8 46,2 1.9 1.6-2,7 44.3 116-174 27 .4-34.6 24 40.2 0.3 o. 2*0, 3 40,9 l.O 0.1-1.2 42. 2 2.3 t.0-1.0 39.9 121* 163 34.4*)~.9 Overall fleon and Range 49.9 0,1 *0.4-0,4 49.8 o.o -0.3-1.2 50.7 0.9 -0.1*3.0 49,8 56*ll5 8.0-39,9 I>ec l 37,3 o.o -0.1-0.0 37,3 o.o 0,') 38.6 1.3 0,3- 3.2 37,3 72-151 32. 2*33. 7 e 37.4 -0.3 *0,9-0.0 37,3 *0,4 -0.1-0.1 37.8 0,l -0 . 2-0,4 37. 7 70* 151 43.9- 122.8 1' 38,2 O, l -0.1-0.1 38.2 O. l -0 . 1-0.1 38.8 0,7 0 . 2*1.2 36.1 158*175 59.0*86.5 22 36, 3 o.o o.o 36.1 -0.2 *O. 2*0, l 39.3 3.0 2.6* 3.4 36.3 156*172 38. 3*4l. l 0Y81'.J11 ~~81\

and Rans* 37.4 o.o -0.9-0.1 37.3 -0.1 -0.1-0.1 38.6 1. 2 -0. 2-3.4 37 . 4 70* 175 12. 2-122.e j' .

I *

~

_ r.

i.

7.2-28

TABLf. 7 .'?., )-6 Catch per effort (number per 10 min haul) for fishes collected by a 16-Ec semi-b.nltoon tnwl at stations in and outside the thermal plume of the Peach Bottoni Atomic Power Station Units No. 2 and 3, Conovingo Pond, July-December 1974.

rllll:\e Increased tncrensed Flow and *reml'!crature Tcml'!eratu.!'e Pcril!hcri Control Station 450 451 Mean 470 471 473 ~Jean M~an 452 472 474 Ne an 453-No. of Species l7 23 25 27 15 17 28 31 19 21 16 25 23 No. of Hauls 138 137 27S 137 136 132 405 680 136 \3) 129 398 136 Species

!i* rastrota "'* -Id*

Q. ecpecli°Ml.ll!l

~- masguinung:i:

£* 3Ut'OtU9

c. carp to lj. mtcroeagon

!!* c!:i'.soleuca:s 0.06 C'l'r

\1 0.10 O.lG 0.31 0.05 0.11 0.15 1.54 5.47 0.25 0.01 0 * .32 0.07 0,04 0.55 0.83 2.23

o. to 0.43 1.72 1dit 0.07 0.08 0.01 0.21 0.92 0,05 0.67 0.02 0.60

~'r-Jtt

1. 12 0.01 0.19 l!*

H.

amoenus hudaonius 0.45 0.49 0.47 5.87 0.50 0,04 2.17 1.86

~

0.17 o.:n 0.32 0 *.30 l,25

}!. procne 0.01 .,..,,

~'*

t!* rubellus 0.01 ** **

ti* sei loecerus 0.02 0.17 0,0') 0.08 0.03 0.07 0.04 0.01 0.01

f. notatus 0.01 0.01 0.42 0, 14 0.11 0.01 ** 0.01 0.03 0.01 0.39 0,05 0.05 0,17 0,13 0,07 0.02 0.04 0.04

"='* !;Y.l!.E..1.nu' **

Q. comnersoni H. nlgricans

.,,** 0.02 0.01

~;'fr

• • 0.01

~*

M. macrolegidotum 0.02 0.01 0.03 ** 0.01 *°I< 0.01 l* catus

1. nntalis 0.02 0.01 0.09 0.01 .,, .. 0.32 0.14 0.05 0.02 0.10 0.02 0.04 0.10 0.02 0.05 0,04 0.06 0.02 ~ !*

0.01 0.01 l* nebulosus

t. P.unctatus 0.01 4,20 **

25.78

o. 01 14.95 0.85 0.04 1.00 0,63 0.47

.341.27 74.2Z 138,01185.35145.81 0.08 11.43 0.23 82.92 121.48 0, 19 0, 17 71.00 0.21 18.39 i:. auritus ** ** **

~. c:i:anellus ** ** f:-lt

_!,. gibbosus 0,l7 0.01 0,14 7,10 0,27 0, 16 2.55 1.97 0,04 0,33 0.05 0,14 0,74 L, macrochirus Q,48 0.16 0.32 9.45 0,40 0.40 3.46 2.74 0.26 O.S-3 0.08 0,29 l.29 i1. dolomieui 0.21 0.08 0.14 0.23

• • 0,08 0.13 0,04 0.02 0,02 0.02 TI. aalmoides ** 0.02 0.01 0.25

• • 0.09 0.07 0.01 '"* ** 0.01 f.. ii~ 0.22 0,3t 0.26 8.89 0.46 0.62 3.36 2.64 1.09 1.39 1.63 1.37 2.99 r_. nisr0111aculatu!!_ ** o.os 0,03 0.04

"'* 0.02 0,03 -J.*-Jt 0.01 *" **

E, olmstedi 2.14 0.16 l. lS. l.50 2.48 o.6; 1.56 1.75 2.66 li.04 Z.19 3.64 10. 21 P'. flavescens ** ** ** ** 0.04

• • ** 0.02 0.02

r:. CaJ!rodes 0,01

~* vitreum 0,03 0.04 0.03 0,07 0,05 0.02 o.os 0,05 0.04 0.04 0.06 0.05 0,02 Totals 8.15 27.96 18,02 383.93 78.84 142.3.3202.74 160.34 16,32 93.0l 126.88 77 .78 36,6.3 Hr Less than O, 01 7.2-29

l-

• ,,/

~ *.: 5 11*1 *

.... e._,.,s".0~~

!h\) ,~ ev:1ll * .*1.r: : ** ,. *

.-aJ.1 . c.  :,1 .r**. t.* *1

~! I) * .,

1 :t* li

~.~ ...-..**.-!--'

~ ..

Map showing the location of Trap Net Stations in the discharge canal and thermal plume of Peach Bottom Atomic Power Station Units No. 2 and 3 in Conowingo Pond.

...}:(*

i.

L

(

i i

}

t 7.2-31

!t:

scale in miles f

.i~

1------452 471

-~------

472 lchthyological Associates

,___ _ _ _ _ 474 Field Station FIGURE 7 .2.J-2 Location of trawl stntions in and outside of the dischnr~c of Peach Bottom Station Units No. 2 and 3, Conovingo Pond, July-Oaccmbcr 1974.

7.2-32

7.3.0 BIOLOGY OF FISHES The biology including food habits, reproduction, age and growth and population dynamics of the common fishes in the Pond

..*:~::;;~:*. was studied. The results are based on data from many specimens *

~

... The objectives of the food studies are to determine: (1) the 1' >~~~::. food and feeding chronology of the common fishes over a 24-hour

" *. ~: ......

period, (2) seasonal food habits and feeding intensity and (3) the intra- and inter-specific food relationships. Studies are made of reproduction to determine: (1) time, location, and spawning temperature and (2) to estimate the reproductive potential (fecundity). The age and growth studies were conducted to determine: (1) the age composition, (2) growth rate and (3) length-weight relationships and condition factor. Population dynamics were considered in order to determine: (1) fluctuation in the year class strength, (2) the natural mortality and survival rates and (3) the rate of angler exploitation in winter.

Natural mortalities which have occurred in the Pond since the beginning of the study in 1966 have been recorded and attempts have been made to determine the cause.

A sununary of the findings on the biology of the selected representative species is included below. supportive data are included in this report or in Robbins and Mather (1974a, b and 1975a,b; see section 4.1 for food habits; Section q.3 for reproduction; Section 4.4 for age and growth; Section 4.5 for population dynamics; Section 4.6 for angler exploitation and Section 4.7 for observations on natural mortalities).

Spawning time was estimated by examination of ichthyoplankton in meter net. The first appearance of larvae in collections was considered the approximate time of spawning.

Eggs were rarely taken in nets because most of the important species build nests and lay demersal eggs.

Studies of the fishery have emphasized a census of the winter fishery because i t is expected that with the operation of the station this will increase. The early fishery in the Pond in other seasons was investigated by Plosila (1961, p. 70-76) and our observations have indicated that the fishery in the summer, fall and spring has not changed substantially from that observed by him.

7.3-1

7. 3. 1 7.3.1.1 Food Habits Young fed mostly during the morning and early afternoon.

The zooplankters, Q~£hni~ spp. and ~~£12~§ spp. were important over a 24-hr. period. Few insects were consumed. Seasonally, young crappie fed primarily on zooplankton. Q~Qbni~ spp. were important from June through October and ~Y£!.Q.Q§ spp. were prominent in stomachs from September through April. Chironomid larvae were eaten in April and May. Seasonally, the following were eaten in small quantities: ~Q§ID!n~ sp., b~2~QQQ~ sp.,

~!Qn~ sp., DiagtOfil£2 sp., amphipods, mayfly nymphs and algae.

The diet was most varied in late fall, winter and early spring.

Feeding was most intense from May through October. These find~ngs generally agree with those of other investigators.

Feeding activity of the adult was most intense in June through October. It was moderate in April, May and November, and least intense in December, January and March. It fed mainly on zooplankton and small fish in most of the spring, summer and fall. Immature forms of aquatic insects (benthis organisms) were eaten in winter. Fish were eaten by adults but not by young.

Although few fishes were eaten, the volume was significant in those which did.

7.3.1.2 Reproduction The white crappie builds nests along the shore, in coves and protected areas. The larvae are concentrated along the shore line of the Pond and in Broad Creek (Table 7.3.1-1 and Figure 7.3.1-3). The highest densities of larvae were found in Broad creek.

i*; The mean gonosomatic index (GSI) values were low in

'.k. January. It gradually increased and reached a peak by the end of x-* May or early June in 1971, 1972 and 1974 (Figure 7.3.1-1). In

> 1973 maximal GSI values and the peak density of larvae occurred iS.*

f '. in late June. The GSI values decreased gradually through

~

• September when the lowest values

• were recorded in all years.

r* From October to December the ovarian weights showed a gradual

........,.~~~~ inc~~as~.

i"~

i.*'*

~

~

The relationship between the peak spawning time based on

\~. GSI values, collection of larvae and water temperature was

-~

.~,.. examined (Figure 7.3.1-1 and 7.3.1-2). Water temperature ranged

• \~

f*.; from 60 to 85 F over the spawning season. Based on the GSI

~ i.. values, peak spawning occurred when the water temperature ranged from 68 to 74 F. Based on the collection of larvae, spawning

7. 3-2

occurred over a temperature range of 60 to 04 F with a peak at 70"'""'

to 82 F.

The spawning time of white crappie determined in other studies is similar to those reported here. Forbes and Richardson (1920., p. 239)., and Hansen (1943, p. 260 and 1951, p. 227) reported May and June to be the spawning time of white crappie in Illinois. Peak spawning occurred in late May and early June.

Eddy and Surber (1947) cited by Morgan (1954, p. 119) reported late spring and early summer as the spawning period of white crappie in Minnesota. In Buckeye Lake, Ohio,.spawning begins in April and extends to early July over a water' temperature range of 51 F to 80 F (Morgan, 1954, p. 121).

In the Pond, the egg production of white crappie in 1974 ranged from 15,387 to 145,378 with an average of 40,535. In the preoperational period the fecundity ranged from 10,595 to 55,353 with an average of 25,724. Both fish length and weigh~ and fecundity are linearly related. Significant differences (P~0.05) between the slopes and elevations of the fecundity and fish weight were not observed in the pre- and postoperational period.

A significant difference existed between the slopes of fecundity-fish length regression lines (P~0.05). However, the elevations (adjusted means) were not significantly different which indicates that the mean fecundity adjusted for length did not differ in the two periods.

A comparison of the fecundity data from other studies shows a large variation irt the mean value (Table 7.3.1-3).

However, the range of egg production is similar. Morgan (1954,

p. 123) reported that. the egg production averaged 39,905 while Huber and Binkley (1935) reported an average of 7,120 eggs.

Whiteside (1964) reported that white crappie in Lake Texoma, Oklahoma produced an average of 53,000 eggs.

7.3.1.3 Age and Growth Although some white crappie attain an age of eight years, most are less than five {Figure 7.3.1-4). The age composition varied considerably between years. The variation in the age composition is primarily due to the production of strong and weak year classes. Moderate to strong year classes were produced (measured by abundance of 0 fish) in 1966, 1969, 1971, 1973 and 1974. These year classes continued their dominanc~ at ages I, II and III in subsequent years. Only fish of the strongest year classes (1966 and 1969) were relatively common at age IV. A virtual absence of two-year old specimens was observed in the 1974 catch. This is primarily due to the poor year class produced in 1972, the year of the Tropical Storm Agnes.

7.3-3

The growth of individual year classes differs (Figure 7.3.1-5). The one year fish of the 1969, 1971 and 1974 year classes had above average growth. The 1967 year class had below average growth at age 1 but it was average at succeeding ages.

The 1969 year class had below average growth after age I. some of the observed differences in the growth rates of older age groups of various year classes reported here are probably due to small sample sizes.

Yearly differences in growth patterns of the whit9 crappie population from 1966 through 1974 were examined by calculating a growth index. The growth of the white crappie population was above average in 1966, 1967, 1969 and in the PBAPS thermal plume in 1974 (Table 7.3.1-4). The growth was av~rage in 1968, 1971 and 1974; it was below average in 1970, 1972 and 1973.

The poorest growth occurred in 1972 which was the year of -

Tropical storm Agnes.

Based on four years of data (1967-1970), one year old white crappie do not begin growth until the water temperature is approximately 70 F (June) (Table 7.3.1-5). Most two and three-year old fish do not resume growth until the water temperature reaches 75 F. Growth appears to decrease when water temperatures are below 70 F which is usually in October.

A comparison of the annual growth of various age groups between the preoperational and postoperational periods revealed that the growth of the one and two-year olds in 1974 was much greater than in the preoperational period. The mean lengths (128-130 and 200-206 mm) attained by these age groups were greater than the eight year averages of 115 ! 2.6 and 179 +/- 3.1, respectively. In 1974 the average** size of the four-year olds r..* (based on small samples) was similar to that of the preoperational period. A comparison of the growth rate of white crappie in various waters is given in Table 7.3.1-6.

The monthly growth of young (0+) and one year old (I+)

fish in 1974 both in the Pond and plume was above the range of observed growth in the preoperational period (Figures 7.3.1-6 to 7.3.1-9). Because of the production of the weak year class in 1972, few two-year old (II+) fish were collected and this precluded a valid comparison. The growth of the small sample of three year old (III+) fish was greater only in September and

-~~ November~~~~-~~~--~~~~~~---~~- -~~-

The age composition of the white crappie collected from the thermal plume and at the monitoring stations in 1974 was similar.

In both areas the catch was dominated by the O, I (moderate 1974 and 1973 year classes) and III (strong 1971 year class) age groups. Few older than III were collected. The poor 1972 year class contributed less than 0.01% of the catch.

7. 3-4

7.3.1.4 Year Class Fluctuations Year class fluctuations in abundance occurred in the white crappie population from 1966 to 1974. The number of young caught per trawl haul was used as the index of relative abundance. Trawl data indicate that the 1966. 1969 and 1971 year classes of the white crappie were strongest and were 33 to 170 times more abundant than the weakest 1970 and 1972 year classes (Figure 7.3.1-10). The 1974 year class (postoperational year) was 4 to 11 times stronger than the 1967, 1968, 1970 and 1972 year classes. Production of young fishes in 1974 ranked fourth in abundance in comparison with the preoperational years. The year classes can be ranked in order of decreasing strength as follows: 1969, 1966, 1971, 1974, 1968, 1967, 1973, 1972 and 1970.

7.3.1.S survival Rates Annual survival rates (s) of white crappie were estimated from trap net catches. Because of large natural fluctuations in recruitment, survival rates were computed for individual year classes. Two estimates were made; one included all age groups and the other was between age groups I to III since the catches of fish older than three years were low and fluctuated considerably.

• The estimates (Table 7.3.1-7) by the Heincke (1913) and Jackson (1939) methods were consistently higher than those using ""'""'

that of Robson and Chapman (1961. p. 182) method (see Ricker, 1958, p. 41 for methods). The estimates using the Robson and Chapman method are statistically unbiased and are less subject to sampling error. The weakest year classes (1967 and 1970) had the highest survival rates. However. these estimates may be not valid because of small sample sizes and large confidence intervals. The age groups II and IV of the 1970 year class were more abundant than the age groups I and III, respectively (Table 7.3.1-8) but this would mean that more fish survived than the actual number present which is impossible. The moderate to strong year classes had similar survival rates, particularly during age I, II and III.

survival rates between the successive age groups of a year class were estimated (Table 7.3.1-9). The lowest survival rates were observed in 1972; the strong 1971 year class had the lowest survival rate between age I and II, in the 1970 year class it was between age II and III and in the 1969 year class it was lowest between age III and IV. The low survival is likely the result of Tropical Storm Agnes in June 1972. The survival rates in years other than 1972 were similar.

Since the calculated survival rates did not change in 1974, it may be concluded that losses due to impingement at the

1. 3-s*

vertical traveling screens at PBAPS must be negligible. Few were impinged. As a predator PBAPS imposes an additional although negligible source of mortality. Impingement losses may be considered as a type of fishing mortality which varies with season.

The impingement data for the white crappie from January through March 1974 were compared with the angler catch per effort during the winter in 1973 and 1974. PBAPS impinged 0.25 to 26.50 crappie per 12-hr. period in January to March 1974 (average 12.84). The angler caught between 26 to 50 crappie per 12-hr.

period in 1973 and from 5 to 46 in 1974 (overall average 34.20).

Thus, mortality attributable to PBAPS is less than that caused by one angler over the same time period *

<r - - - - - - --- -~-------------~

7.3-6

A1l~~f!i.}

Cat.:h of larvaa of rcpras..nt:itlvc l*"l*~r tunt fl*hc* ( S. 25 1!111) (11W11b\lr l'"r lO-n1ln toll) Ut VGridUS l11~hore locutiORll ~UC~~~.'. ~* c**:,,'

pi:coporatlonnl (l967-L97'lJ) and po~to1>9rntton.il (l974) retiods tn Co11owi11gu l'onJ. Plmoph:>l<!s ~. tctalurus punctistua;:*;*, , * .. :.* ...

;~ and ~licroptcrus salmoidc' not collcct~d, ' . . ** ::.:: * .

. ::}:~;;::,K *. '., \,.,.

Location  !'fuddy Cr.,.,k Ila st sh.,rc off West 9hore Brood Clcn llopltin!l Ease shore fr0(1l Cnoowtn*~~*: *, . /  ::

Peach ll<Jttora Creek Cov~ Cova Johnsons l$l~nd Pe.tel\ Sottooa Creek *.. ~.-:.::7 *.: *.

. *: ... Station abuve dhchargoa to to WllJcat l\1nne\

• • , ~ .

discharge Maryland State Llne *

.~_; :.;~ ,/ . .. /

.:..r:!;*;; 1*::..... ,

Spoclcs  :

o. ccpt!dln.num 1969 o.oo o.oo o.oo o.oo 1970 o.oo o.oo o.oo o.oo * *..

1971 o.oo o.oo 0,00 o.oo 1972 o.oo 0.16 5.41 0.52 0.21. 0,68

• 1973 o.oo ),20 o.oo o.oo o.oo*,..

1974 0,28 5,68 o.t2 O, l? o.oo

• .' ll, spiloptorus 1%9 0,16 o.46 o.oo o.5a 1970 0,14 0.19 0 . 18 0.10 1971 o.oo o.oo 0 . 02 0,03 1972 0,00 o.oo o.oo o.oo o.oo o.oo 1973 o.oo 0. 32 o.oo o.oo 0,24 1974 2.12 0,06 2,36 1. 76 0.28 L. rnacrochlrus 1969 o.44 0,55 0,25 O, lO 1970 o.oo o.oo 0,06 o.os 1971 0,79 0.01 ll,44 4.67

",. 1972 o.oo o.oo o.oo o.oo o.oo o.oo l'J7J o.oo o.oo o.oo o.oo o.oo 1974 o.oo o.oo 0,00 o.oo o.oo Lcpomts spp.

1969 L2, lS 10,SS 1.so 14,28 1970 8,00 4.57 l)J,26 26.'>3 1971 2.57 1.50 7.29 J,28 1972 o.oo o.44 s.n 4,52 6,52 11** 00 1973 0.12 5,58 u.oo 5.24 13.76 1974 l,24 12,18 6,64 J,88 10.~2 M. dolomicui 1969 o.oo O.OG o.oo o.oo 1970 0,00 o.oo o.oo 0,00 1971 o.oo o.oo o.oo o.oo 1972 0,00 o.oo o.oo o.oo o.oo o.oo 1973 o.oo o.oo o.oo 0,00 o.oo 1974 o.oo o.oo o.oo 0,00 o.oo o.oo

!'. snnuhrit 1969 4. 66 5,28 3.88 0,69 1970 2,00 8.22 20.75 3.57 1971 2,07 4,78 15.13 0,86 1972 O,JO 0,16 16.57 1,60 4,92 12,00 1973 0,24 2.32 l.88 1.24 2.12 1974 0.12 6,62 2.64 1.52 9,00

s. vttreum 1969 o.oo 0.03 o.oo o.oo 1970 o.oo 0,00 o.oo o.oo 1971 u.01 0,06 O,lO 0,08 1972 0,00 0,28 o.os o.oo 0,00 o.u 1973 o.oo 0,06 0,12 0.24 o. t2 1974 o.oo 0,06 o.oo 0,01) o.oo 7.3-7

TA!'ll.F. 7,),1-<'

Catch of larv:io of ruprcscutGtivc lm11ortnnt fishes ( ~ 25 nvn) (1tunibcr per 10-inil\ to'.*) 11t Tra.n~cct St'1tlons on the wo~t shoru, mid-pond ;ind wc~c sh"r<: tlurinn thu prc.,por4tionill (L967-L97l) and postop~ratlona.L (1974) periods in Conowingo Pond, Location \lfo:ST Sl!OKE mn-rolllll EAST SHORE Station 56Z 564 567 570 560 563 565 568 561 566 569 575 576

!l* ce~cdlanum 1969 o.oo o.oo o.oo o.oo o.oo o.oo 0.00 0.00 0.00 o.oo 1970 o.oo 0.00 0.00 0.00 0.00 o.oo 0.00 0.00 o.oo o.oo 1971 0,00 0.00 0.00 o.oo o.oo o.oo 0.00 o.oo 0.00 0.00 1972 0.03 0.00 o.oo o.oo 0.00 0.00 0.00 o.oo o.oo o.oo 1973 0.08 O. ZS 0.13 o.oo 0.00 0,011 o.oz 0.06 o. 15 0.40 1.92 0.64 0.34 1974 o.oo a.oz o.oo 0.04 o.oz o.oo 0.02 0.02 o.oz 0.33 0.21 0.03 0.03

.!!* seiloeterus 1969 0.14 0.05 0,05 O.Z9 0.03 o.oz 0.06 o. 21 0.18 o.oo 1970 o.oz 0.13 0.05 0.09 0.00 0.17 0.01 0.14 0.10 0.03 1971 0.06 0.00 o.oo 0.06 0.42 0.02 0.07 0.15 0.12 o.oo 1972 0.00 o.oo o.oo 0.00 0,06 0.03 0.11 0.00 0.08 o.oo 1973 o.oo 0.00 0.02 o.oo 0.00 o.oo o.oo 0.02 0.17 0.02 0.00 0.00 o.oz 1974 0.08 0.07 0.00 0.48 0.33 0.17 0 *. 02 0.11 l,eo 0.05 O.Ll 0.20 0.20

!* natatus 1969 o.oo 0.05 0.00 o.oo o.oo 0.00 0.03 o.oo o.oo o.oo 1970 o.oo o.oo o.oo o.oo o.oo 0.00 o.oo o.oo o.oo a.co 1971 o.oo o.oo o.oo o.oo o.oo 0.00 0.00 0.00 0.00 o.oo 1972 0.00 0.00 o.oo 0.00 o.oo c.oo c.oo 0.00 o.oo o.oo 1973 o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo 0.02 0.02 O.llO o.oo o.oo 1974 o.oo 0.00 o.oo o.oo 0.04 o.oo 0.00 o.oo 0.04 o.oo 0.02 0.00 0.03 1*  !!.!!..~

1969 8.62 11.00 17 .39 3.85 4.29 a.oz 0.44 9.00 1.28 0.92 1970 4.32 4. 77 7 .52 2.02 0.56 l. 31 2. 33 2.18 0.48 0.81 1971 0.20 0.47 1.53 1.96 0.04 0.07 0.23 1.19 0.08 0.26 1972 a.oa o.a3 o.aa 0.03 0.03 a.oa a.oo 0.00 a.oa o.oo 1973 2.87 2.62 3.85 0.33 1.86 3.17 1.26 0.69 1.42 l.96 0.51 1.08 1.21 1974 2. 77 2.30 2.59 1.85 1.51 1.45 0.62 1.20 l.J4 a.22 0.14 0.33 0.92 1* macrochlrus 1969 1, 71 1.a1 a.39 o.2a 0.34 0.51 0.42 1. 54 14.26 l0,3a 197a 0.02 a.23 0.02 a.oo a.oo 0.19 a.05 0.02 2.92 0.22 1971 0,30 0.57 o.oz 0.46 0.31 1.15 0,40 0.89 14.63 l.S:J 1972 0.03 0.03 o.oo 0.03 o.ao a.a7 o.oa 0.03 0.11 o.oo 1973 o.oo a.ao a.aa o.oa o.ao o.ao a.aa a.aa 0.00 0.25 0.04 o.aa 0.09 1974 a.a2 o.a2 a.aa a.a4 a.oo a.a2 0.02 0,04 0.13 0.18 0.43 0.01 0.12

£!. dolomleul 1969 0.05 0.07 0.03 a.10 0.08 o.*10 a.24 a.26 a.13 0.16 197a a.az o.aa a.oa 0.07 o.ao o.ao 0,00 0.01 0.02 0.00 1971 o.oo o.oo o.aa a.oa a.a2 a.ao a.ao a.ao a.ao a.05 1972 a.ao a.oa a.aa a.oa 0.03 o.aa o.oo o.ao o.oo 0.04 1973 o.aa a.oo a.aa a.oo a.oo o.oo o.oo o.oo o.oo 0.04 o.oo o.oo o.oo 1974 0.02 0.02 o.oo 0.00 o.oo o.oo 0.00 0.00 o.oo o.oo a.oz o.oo o.oo tJ. admoides 1969 o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo o.oo a.oo 1970 0.02 o.oo 0.02 0.00 o.oo o.oo o.oo 0.02 o.oo 0.00 1971 o.oo 0.00 0.00 o.oa o.oo o.oo o.oo o.ao o.oo a.16 1972 o.oo o.oo o.oo (1,00 o.oo o.oo 0.00 o.oo o.oo o.oo 1973 o.oo 0.00 0.00 0.00 o.oo 0.00 o.oo o.oo 0.04 0.04 o.oo o.oo o.oo 1974 o.oo o.oo o.oo 0.00 o.oo o.oo o.oo 0.00 0.00 0.00 0.00 o.oo o.oo

!* nnnularl.s 1969 1.19 6.21 0.68 0.17 0.03 1.02 0.18 1.41 2.59 6.a3 197a 0.55 o. 73 0.12 0.20 a.oa a.a6 o.aa a.07 0.42 a.oe 1971 0.42 1.09 a.35 0.13 a.15 a.33 a.26 0.66 7.31 3. 95 1972 0.18 a.06 a.18 a.05 o.oo 0.07 0.04 0.10 0.16 0.01 l97J a.11 0.06 0.27 a.14 0,06 0.06 0.02 0.24 0.06 C,09 o. 3a 0.04 0.06 1974 a.20 0.12 0.11 0.22 0.09 o.1a 0.07 0.16 0.21 0.48 0.84 0.23 0.13 Lcpomts spp.

1969 4.8J- .. 0"'3J~0 ..-32-.-*- - --*-

. - -a.11- -a. 0.a7- . -a. 33--.-~-0.67--a.-21--5,46-..-- ~.- --

1970 l.15 a.OS 0.69 0.11 0.26 o.oa 0.26 0,66 0.19 l.49 1971 0.48 a.64 0.98 0.39 a.56 0.33 3.14 0,83 13.86 15. 32 1972 o.oa o.oa a.ao o.oo o.oo a.oo o.oo o.ao o.oo a.oo 1973 0.32 a.34 0.18 0.19 0.06 0.15 0.13 0.44 0.31 0.89 0.68 1.40 1.57 1974 0.10 0.27 0.18 0.96 a,15 o.ae 0.12 0.13 0.21 0.38 0.45 0.80 0.63

~* vitreum

~ 0.02 o.oa o.ao o.oo a.oo o.ao o.oo a.ao o.oo a.oo 1970 0.00 o.oa o.ao 0.00 o.oo o.aa o.oa o.ao o.oo a.oo 1971 0.22 0.13 a.02 0.02 a.02 0.02 a.oa o. 15 0.12 0.00 1972 0.09 0.03 a.04 0.03 0.06 0.00 a.oo 0.08 0.03 0.00 1973 0.02 o.ao a.oo a.OS a.02 0.02 0.17 a.ca 0.06 0.02 0.02 0.02 0.04 1974 o.a3 o.ao o.ao o.oo o.oo 0.02 o.oo o.oo 0.00 0.02 0.0?. 0.00 o.oa i.

~ *.

7.J-8 1~ .

l:...

TA!\LE 7,),1-3 Comparison of fecundity data on white crappie fr0111 various studies.

Portion of the data reproduced from C~lhoun (1966). Original measurements in inches converted to millimeters

• Sample Total Length Number of Egss Source Size (mm) Range Range Mean Morgan (1954) 56 149-330 970-213213 39905 Huber and Binkley (1935) 42 2900-14750 7120 Seifert (1969) 24 211-316 22880-194100 Whiteside (1964) 25600-91700 53000

?resent Study (1971) 30 161-2491 10595-55353 25724 Present Study (1974) 39 176-3291 18764-145378 40535 Combined (1971-1974) 69 161-3291 10595-145378 34096 ' "'""

1Original measurements in fork length converted to total length using the relationship TL* 1.213. + 1.028 FL 7.3-9

TA:IL1': 7,3,1~5 Continued, ACE GlltlllP

(( lC [

• • Mean NYmber Percent Numhl*r P~ret.*nt NuC1bcr P!i!rcl*nc Wati?r of with uf "Ith .,r wlth l'c111p Fish 1\nnulu.s nsh Annulll5 Fi.*h Annulu1 (F) 1?09 MAY 1-8 9-16 17-24 67.0 7 0.0 6 0.0 14 o.o -.,..., .- .... - ~---

25-31 70.0 50 44.0 l o.o 5 o.o JUNE 1-8 9-16 75 . 0 13 LOO,O 6 66.0 39 o.a 17-23 75. 5 23 100.0 l 100.0 10 o.o

'; 211*JO 78.0 l8 L00.0 3 100.0 15 so.a JUT..Y l*B 18.5 24 laa.o 2 100.0 11 qa,9 9*16 8a.o ll 100.0 l iao.o 11 9a.9 11-21. 81.0 29 laO.O 21 100.0 25-31 78. 5 5 100.0 2 100 . 0 1970 M1\'l 1-8 9-16 17-24 66.0 )11 o.o 10 o.o o.o 25*31 70.5 22 13.6 JUNE 1-8 71.0 13 38.5 LL o.o 4 o.o 9*L6 74.0 &O 93.3 )5 o.o 4 o.o 17-23 74.0 L 100.0 l o.a 24-30 74.0 33 93.9 2J 4.3 2 a.a JULY 1-8 9-16 74.5 36 100.0 16 ~8.7 o .a 17-24 76.0 2 50.0 25-31 8l.5 ')4 97.0 L6 SL. 2 J3.3

• • Mean of surface water temperature at sampL Ing stationa.

7.3-12

~*: ***

r ~;~;

(~f:;rz;;jf;*

U.LE 7.3.1-6 .

A comparison of calculated growth rates for white crappie, Pomoxis aPnularis, ft'olll *: *..xq::;i**:~+,;'i"~. .{.;.

various p4rts of the country. Portion of the data (*) reproduced froll\ LaFalll\Ce (1960*;:. ~; : ~)>t::<

Swr:~~l -**~*:~.in<h" ~" ~-or::d t:l:ll~~:*:,~ue VI VII Vlll >i)~~l~ .

carter (1953)* Kentucky Lake, Ky. 117 201 264 302 325 , ..

Geibel (l959a)l* East Park Reservoir, Cal. 93 171 195 281 .*;*

Geibel (1959b)l* Stony Gorge Reservoir, Cal. 77 163 213 237 Hagy (1956)1* Anderson Reservoir, Cal. 152 186 Ball et al. (1954)* Oklahoma State Average 74 150 198 249 302 335 361 381 Hansen (1951) Lake Decatur, 111, 196 229 267 277 290 330 I

Starret~and Fritz Lake Chautaugue, 190 234 262 283 300 i (1965) Ill.

i Jackson (1957)

• Lower Spavin.aw, Okla. 117 208 239 284 338 Morgan (1954)

• Buckeye Lake. Ohio 58 107 150 193 231 259 302 Stevens (1958a)* Lake 'Moultrie, s.c. 56 208 287 340 371 381 378

• .... Steve111 (1958b)

• Lake Marion, s.c. . 48 17S 251 28li 312 320 331 i

Present Studyl Couowingo Pond, l'a. 113 184 226 254 291 327

1. Origln&l measurements in fork lengths converted to total length* by the following relationship: TL

• 1.213 + l.028FL.

lI:

I I

I I i I

I 7.3-13 1.;

TABLE 7.J.l-7 Estimates of annual survival rates of various year classes of white crappie, Pomoxis annularis in Conowingo Pond as calculated by the methods of Robson and Chapman, Reineke, and Jackson.

Robson and Chapman Heineke Jackson ALL AGE GROUPS 1966 0.415+o.041 0.519 0.519 1967 o.444+o.2oa 0.480 0,481 1968 0.343f0.075 0.408 0.408 1969 0.34S+/-o.029 0.410 0.411 1970 0.62o+o.578 0.669 0.752 1971 o.302+/-o.046 0.354 0.384 AGE GROUPS I-III 1966 0.391+/-0.042 0.505 0.584 1967 0.394j:0.221 0.449 0.531

. 1968 0.321+o.075 0.397 0.429 1969 0.248+/-o.023 0.403 0.443 1970 0.5:32+o.718 0.628 0.688 1971 C.302io.046 0.354 0.354

~ .

~_: ..

7.3-14

TABLE 7.3.1-8 Catch per effort (number per 100 hr) for various age groups of the 1966-1974 year classes of white crappie, Pomoxis annularis, collected by trap net during the.preoperational (1967-1973) and postoperational (1974) periods in Conowingo Pond.

AGE GROUP Year Class O* I II III IV v VI VII 1966 161.06 121.40 43.44 8.05 0.73 0.25 0.02 1967 7.99 7.42 4.02 2.05 0.74 ** 0.04 0.01 1968 10.85 63.92 34.17 7.97 1. 71 0.15 0.02 1969 302.40 417.46 218.72 62.91 7.51 1.08 1970 0.96 0.81 1.18 0.19 0.27 1971 243.09 182.37 78.34 21.74

... . 1972 1.44 0.62 0.07 1973 30.77 16.07 1974 63.95

• Collections taken from July through December.

• " Less than 0.01

' TASLE 7.3.1-9 i'

. *~

j".

Estimates of annual survival rates between two successive age groups I'

i of individual year classes of white crappie, Pomoxis annularis collected by trap net in Conowingo Pond.

t I I/II II/III III/IV IV/V V/VI VI/VII i"

f.

Il Year Class 1966 1967 0.7538 0.5418 0.3578 0.5100 0.1853 0.0907 0.3610 0.3425 0.0800 0.3000 I .

1968 0.5346 0.2332 0.2142 0.0877 0.13~3 l 1969 0.5239 0.2876 0.1194 0.1438 i 1970 1971 0.4290 0.1640 0.2775 )

l 1972 0.1129 ll-'

7.J-15

• .~ . 1974

,....___ n = 612 80 ... 80 60

/

/'*"

,~ .,,,~ ',..,

............ """ 60 40 .........-... --

'*...... 40 20 *20 80 1973 n = 892 80 60 ~

µ,.,

~ 60 trl 40 zA H 40 ~ - ---~

20 f-1 u

H 20 ~

w

~

0 w e~

(/l BO 1972 H n = 1376 0

80 8 60 ~

~

60 ~

40 z 40 <

20

~

I ~

20 80 1971 80 60 60 40 40 20 20 0

J F MAM J J AS 0 N D FIGURE 7 .3 .1-1 Seaso11al variations in mean gonosomatic index (solid

- - - - - -li,ne) - an<l water- temperature (dashcd - line)- o[-_white - - - - - -

crappie, pomo:<is ~1!'._1!!._t]:_a_;_is col!ccted during the preopcrational (1971-1973) and*postop~rational (1974) periods in Conowingo Pond, 7.3-17

P!fl'!RE 7,).1-2 Range of surface WRter temperatures at which larval fishes (25 mm or less in size) were t3ken in Conowingo Pond in 1969*l973. Narrow lines: temperature range at which fish 14rvae were collected; llide bnnds: temperature rnnge of maltimal density, Temperature (F) 55 60 65 70 75 80

!!* cepedlanum

!* ~pilopterus

!* ~ - - - - - - -... It l* punctacua

!:* 1Mcrochirus tl* dolomi.eui 1:!* salmaidcs

!* !:'nnularls tepomts spp.

~* vitreU111

• !nsufficLent number* of larvae were taken co determine periods or maximal density, l*

1'.

7.3 ... 18

• • ~*.:.

MUDDY RUN RECREATION LAKE MUOOY RUN PUMPED STORAGE POND

- MUDDY CREEK PEACH BOTTOM ATOMIC POWER STATION STONEWALL POIN.T PEACH BOTTOM BEACH WILLIAMS TUNNEL STATE LINE-P_A_.- - - - - -

MD.

AVERAGE CATCH OF LARVAE PER 10 MIN TOW

-- ---~ - **- -:<- 0-;49

• 0.50 - 0.99

• 1.00 - 4.99

• 5.00 - 9. 99

"' 10.00 - 19.99 0 ~ 20.00 FIGURE 7.3.1-3 Relative catch per effort of white crappie, Pomoxis annularis larvae

( '5_ 25 mm) at plankton net stations in Conowingo Pond, 1969-1973.

7 .3-19

MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE PONO MUDDY CREEK PEACH BOTTOM ATOMIC POWER STATION STONEWALL POINT PEACH BOTTOM BEACH

• WILLIAMS TUNNEL

• • .. STATE LINE-P_A._ _ _ __

MO.

... WILDCAT TUNNEL

~ .

..~ ...

~*

~**.

AVERAGE CATCH OF LARVAE PER 10 MIN TOW

• < 0,49

• 0.50 - 0 .. 99

• 1.00 - 4.99 GLEN .COVE ct 5.00 - 9.99 f) 10.00 - 19.99 9 ~ 20.00 FIGURE 7.3,1-4 Distribution of channel catfish, Ictalurus punctatus larvae ( $_ 25 mm) at plankton net stations in Conowingo Pond, 1969-1973, 7 ")_".)A

340 320 VII

- - - - - - - ----- - - - - - - -- -- e - - - - - ---VII v~/jVI 300 280

---

1*----------VI 260 240

---

.J--*------:~:- --v 220

-! 200

~

~ 180

~

e ---.Li~~----- e II

---

II f

I ~ 160 l 0 II . s:z.

a i ~ 140 e I !I 120 I I *I I

- - -*- - - - - - e_ - - - - - ~ - - e - - - - - - - - - -I 100 e I 80'--~~~-,.------,...---..,.------r----,.--~..,....----r~~~..--~----

- - - 66_~67_ _68 - 69 ~70 . 72-- - - -

Year Class FIGURE 7,J,l-.5 Growth of the 1966-1974 year classes of white crappie, Pomoxis annularis collected by trap net in Conowingo Pond, Open circles - thennal plume.

7.3-21

J

130 0 8 i-120 110 LOO 0

0

$ ~

c f<

~

j 90

~

0 80 70 60

$ o Thermal Plume Mun

• 1974 noni.toring Station Hean

- rreoperational Mean (1966* 1973) 50 AUC SEP OCT NOV DEC FI':1HRE 7, 3, l-6 Monthly growth of the young (0) white crappie, Pomo><ia annulari.s collected by trap net during the preoperational (1966-1973) and postoperational (1974) periods in Conowtngo Pond and thermal pl\Dlle, Vertical line - range, rectangle

• 2 standard error of mean, hori*

zontal line

• preoperational mean, open circles - thermal pl1.J111a mean, closed circles - 1974 ~ean, 210 0

o Thermal PlUl!la !lean 200

• 1974 l!onitoring Station ~lean

• 0

- Preoperational Hean O j"

(1966*1973)

• 190 0

• J*.

• 180

! 110

~j 160

~

Ii! 150 140 130 120 110 100 Jllll JUL Al.Xl SEP OCT NOV DEC Monthly growth of the one year old (I) white crappie, Pornoxia annularis collected by trap net during the preoperational (1966*1973) and poatoperational (1974) periods in Conovingo Pond and thei:mal plume.

Vertical lines

• range, rectangle

• 2 standard error of mean, horizontal llne

• preoperational mean, open circles

• thermal plume mean, closed circles

• 1974 mean, 7.1-22

JUN JlJL SEP OCT NOV O!;C PJC1URF. 7.J.1-6 Monthly growth of the two yo4r old (II) white crappie, !_Oll\oxis annularia collected by trap net during the prec.perat1on4l (1966-1973) and post-operatianal (1974) per1oda in Conowingo Pond and thermol plume. Vertical line

• range, rectangle - 2 standard error of mean, horizontal line

• preoper4tioual mean, open circles - thermal plu~ mean, closed circle* -

1974 mean.

f

(.

It* 270 f

I 260 t 2.50 I

240 0

1230 0 i!l

~

~ 220

...i:1 210 0

200 I 190 180

-*-** --- -- - - - - - - 0 l'h<!nnal Plume t*!ean -

• 1974 Monitoring Station i:ean Preoperational Neen (1966-1973)

I 170 JUN Pir.tJRE 7 *.3.1-9 JUL ,,u:; SEP ocr liOV DEC Monthly growth of the three year old (III) vhite crappie, Pomoxis 4nnularis collected by trap net during the preoperational (1966-1973) and poat.;pera:-

tional (1974) periods in Conowingo Pond and the::mal pl11111e, Vertical lines

• range, rectangle - 2 standard error of mean, horizontal line - preoperational mean, open circles - thermal plume mean, closed circles

• 1974 inean, 7 .J-23

140

..... 130 White Crappie

~ Cha!1Ilel Catfish

..... 120

~

- t>O

§ 0

50 40

'M 0

30

-54J

\11

~

c.> 20 10 ' .......

.... . . .*,l* ...... ............ ---..

1966 1967 1968 1969 1970 1971 1972 1973 197!+

FIGURE 7.3.1-10 Year class strength of white crappi.e (solid line) and channel catfish (d<lshcd line) expressed as the ctttch 0£ young per trawl haul in Conowlngo Pond.

1;

/..

7.3-24

7.3.2 7.3.2.1 Food Habits Subadults and adults fed most heavily during daylight hours in conowingo Pond. The principal food during most of the 24-hour period was zooplankton. The food in mid-morning . was fishes and in the early morning it was insects. From.July through November zooplankton was the principal food. In August and October fishes were important in the diet. In November amphipods were significant food items. Feeding activity decreased in November. Other investigators in other areas reported (see Mathur, 1971) that fishes, insects, crustaceans, molluscs and plant seeds were common food items.

7.3.2.2 Reproduction The channel catfish spawns in nests near the shore.

High gonosomatic ratios indicate that the spawning peak occurred in June and July in the Pond. Spawning occurred at water temperatures of 62 to 82 F. Peak spawning occurred at 74 to 81 F

{Figure 7.3.1-2). The gonosomatic index was highest at 75 F.

The larvae were usually taken in June through August, with a maximum abundance in June or July, in most years. The densities of larvae were higher alonq the west shore and mid-Pond, than along the east shore {Table 7.3.1-1 and 7.3.1-2 and Figure 7.3.2-4).

The fecundity of 31 channel catfish in the preoperational period ranged from 1,049 to 11,898 with an av~rage of 2,546. The fecundity of 13 channel catfish in 1974 ranged from 1,014 to 7,396 with an average of 2,349. Although the small sample size precluded a statistical analysis of the fecundity data, the eqg production in 1974 (postoperational period) was well within the range of variation observed in the preoperational period.

• 7.3.2.3 Age and Growth Most of the specimens which were aged were less than eight years. Some were 9 to 16 years. Most growth (50%}

occurred in the first four years (Figure 4.2-1). For ages VI to

-~--x.zi ,_ttie _~n_riual ____A.Yera_gJ;! _i_ncr~a~e_ in length was_ up to 12 mm_ pe_r _ __

year.

Differences in growth occurred between year classes (Figure 7.3.2-2). The growth of age group I was greater than the 10 year mean (1958 to 1968) from 1958 to 1961 and was less in

~-*  : 1963 and 1965 through 1967. The growth of the 1959 year class was consistently above average. Growth of the 1960 year class 7.3-25

~;

I f.-,

was good for the first three years. It was poor for the 1964 year class. A comparison of growth rates in other waters shows that the growth of catfish in Conowingo Pond is relatively slow, especially after the first three years (Table 7.3.2-1).

The growth of the young and yearling channel catfish appears to be related to water temperature (Figure 7.3.2-3). The specific growth rate (percentage growth completed per unit time) was highest when the water temperatures exceeded 70 F. The growth rate declined at water temperatures less than 70 F.

7.3.2.4 Year Class Fluctuations The differences in year class strength of the channel catfish were not as pronounced as were those of the white crappie (Figure 7.3.2-5). The 1969 year class was the strongest and three times more abundant than that of 1974 (postoperational year). The 1974 year class was 2 to 10 times more abundant than the weakest 1967 and 1972 year classes. Like previous years, th~

production of young channel catfish in 1974 was greater (about three times) in Zone 405 (off the Station) than in Zone 406 and 408.

7.3-26

l.

r I~ * ;., '

,.~. ':"i[ :~~*"'"~'.r*"'*-

~

" .* --...-."'*t-,..................

TABLE 7.3.2-1 ~;:;~1l(

,\ comparison of the calculated grovth ntc* for channel catCbh, !ctdurus punctacua, fro~**~~*

partl of the countey. 03U fro.'1l othor studies reproduced from <:arl4ndar (l'.l69, p, .548), Ortg * ***t Lo Lnchu converted into ml.lll111eters. **.-,*:.: .'.;~ ..

Source Place A c CroU'll I It* 111 IV V VI Vll. VIII IX X XI XU XUI Stevena (1959) tal<e Moultrie, s.c, 86 185 284 368 442 531 602 665 726 773 807 8S3 rogle (1963) Lake Oahe, S.D, 122 201 267 348 437 513 549 602 663 Conder and ~ntucky t..ke, B.oftarth (1965) Tenn, 109 170 221 262 307 363 424 *495 566 640 l!el.cu (19155} Coralville L41ce, Ia, 84 157 211 267 320 351 384 411 381 Marr:olf (19SS) Lake of Ozark*, Mo, 53 117 168 206 241 269 295 325 11Arriloo (1957} Mte1i11ippi River, La,66 lSO 211 254 274 315 Muncy (1959) De* Moine& River, 46 124 196 257 312 381 442 490 546 617 645 640 676 Ia. *,.*.

Bancock (19S5) Canton Lalca, Okla. 94 208 305 386 442 536 594 Orr (1958) Ucybuni Lake, Okla. 86 165 224 305 394 472 561

• • • **~

Starratt and Lake Chautauqua, Fritr: (1965) Illinois 348 401 462 523 569 l'reunt Study* Conovtngo Pond, 105 175 lJO 262 294 332 365 402 448 483 529 571 531 497 516 P~.

• fork lengths converted co toc&L length* by the following relat1onahlp: TL

• 5.4S3 + l.13SFL 7.3-27

450 37S

.500 e e~ 450 400 9

M 300

~

~~~~ -_  ;!5 ~22.S

~

300 f, 2.50 5 150

~

200 2 uo 100 75 Incr""'"nts 50 0

H

.... M'

i. > ...> ....... ...

)(

..... ..."'........... '°... ...... ,,................. '°...... .........

0 ...

N "'

PIIJUR 7 .J. 2-l FIGURE 7. J.2-2 Calculated gra11t!\ curv" and annual increments for Calculated grO!orth hlstol'Y of 1958*1968 Y"*r cla111a 236 channel cattlah, ~~u.! punctatus, collcctad of channel catfish, ~!!.!. punctatus, collected from Conollinso Pond, 1~67-1~69, from Cono11ingo Pend, 1967-1~69, Haci~cncal Linet are un11eighted meana of ago groupe.

,r ...,....

7.3-29

1968

~Water Temp. (F)

.7 100

---

Yearling

• • • • Young

.6 90

.s 80

.4 70

/'  ;

.3 I v* 60 ,.......,

~ '\ .._,

~

I *

~ \

I

.2 I 50

~E-4

~ \

~

t:)

u H

~

H

.l -- "'"' ....J I

I \

\ ..

40

~

t.:I

~

i:r.l E-4

~

u w

~

.o 30 t-*

ti)

~

.s 1969 90

.4 .. 80

.3 . 70

.2

/

/--

- """ 60

.1 /

/

50

.o

/

' """ ---- 40 MAY JUN JUL AUG SEP OCT NOV FIGURR 7.3.?-3 Monthly spec.Hie growth rates of yollnZ and yearlin~* channel catfish, Ictalurus ptmctatus, from Conowini;o Fon<l 1 n 1968-1%9 and mean nonthly water temperatures (F) taken at Holtwood, Pcmnsylvania.

f*

~*I .

7.3-30

MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE PONO MUDDY CREEK PEACH BOTTOM ATOMIC POWER STATION STONEWALL* POINT PEACH BOTTOM BEACH e

• WILLIAMS TUNNEL STATE LINE-P_A._ _ _ __

MO.

AVERAGE CATCH OF LARVAE PER 10 MIN TOW

~ t ~ * --- *

- .- < *0 ,49- * - - - - - - - - - - -

• a.so .. o.99

• 1.00 - 4.99 GLEN. .COVE ft 5.00 - 9.99 10.00 - 19.99

• ~ 20.00 FIGURE 7.3.2-4

• .. Distribution of channel catfish, Ictalurus punctatus larvae ( ~ 25 mm) at plankton net stations in Conowingo Pond, 1969-1973.

7.3-11

11.0

..... 130 White Crappie

.I

~ Cha:lnel Ca.tfish

..... 120

~

Ill

~

Nl 50 g

~ 40

"'0

.d 30 u

41 it 0 20 10

• l!>i>6 1%7 1968 1969 1970 1971 1972 l97.3 PIGURE 7.).2-5 Year class strength of whil:e crappie, Pomoxis !!_~laris (solid line) and channel catfish, lctalunis punctatus (dashed line) expressed as the catch of the young per trawl haul in Conowingo Pond.

7.3-32

1.3.3 1.3.3.1 Food Habits The food of small bluegill (21-40 mm) in summer through winter in the postoperational period was mostly cladocerans and copepods. Chironomids were important as food in the winter.

Bluegill at a length of 41-100 mm ate mainly cladocerans and copepods in the summer and autumn. In spring the diet was mostly terrestrial insects, Hydracarina and cladocerans. In winter aquatic insects {mayfly nymphs), amphipods and Bryozoa were dominant food items. Those larger than 100 mm fed mostly on cladocerans and aquatic insects in the summer and autumn.

Aquatic insects and amphipods were most important in winter.

Aquatic insects and items such as terrestrial insects were 1 mportant in spring. -*-Its food- habits in the - preOperational period were similar to those observed in the postoperational period.

1.3.3.2 Reproduction The bluegill builds a nest in shallow water. The spawning period may extend from May through ~ugust with a maximum in June to early July in the Pond. The maximum catch of larvae was usually in June. The highest densities of larvae were found along the east shore between Peters Creek and Broad Creek (Table 7.3.1-1 and 7.3.1-2 and Figure 7.3.3-1). It spawned at temperatures of 62 to 84 F and most occurred at water temperatures of from 7q to 82 F. Calhoun (1966, p. 380) in a review reported that it spawns at water temperature of 67 to 80 F.

The fecundity of 7 bluegill (141 to 195 mm) from Conowingo Pond ranged from 25,159 to 44,895. Calhoun (1966, p.

38.1) *reports egg counts that ranged

• from 2.,360 to . 49.,400 -per specimen.

1.3.3.3 Age and Growth Most of 1,217 bluegill aged were less than four but some reached an age of six years. Some differences were noted in the growth rate of sexes up to an age of five years. The combined data for alL specimens _ show that __ most ~growth_occurred . in ~the first three years by which time it is 176 mm long. The annual increments were greatest in the first two years. A comparison of the reported growth rate in different waters is given in Table 4.3-1.

7.3-33

TA1'LF. 7.J.J-1 A comparbon of grO'llth ratea of l>luegill, lepomls macrocblrus, fro111 various pares of the couritry. Oat.a fro111 other studies reproduced fror.i Calhoun (1%6, p . '371!), Original meumre-ments in 111ches canvurtcd to 111Ulimeters, Source Place Age Crou2 I II III 1V v VI VII VII! IX Bro1t11 and Logan (1960) 11 Montana Ponds 33 61 91 112 127 137 l.SS 175 Louder and L~ia (l9S7) Lake Murphysboro, Ill, 43 74 97 130 147 160 Morgan (1951) 1 Buckaye Lake, Ohio 41 74 104 132 lS2 180 188 196 213 Jlennemuth (1915) Lake Ani1u ab i, Ia. 48 94----119 - 142 160 Ricker (1942) 56 Indiaaa Lakes 40 80 128 173 196 2.LS 244 236 Tharratt (1966)2 Folsom take, Calif, 38 83 128 186 210 230 Bennett et f 1* (1940)1 Homewood !Ake, Ill, 71 114 135 142 147 Lane (1954) Clearvater Reservoir, Mo, SB 107 l4'Z 168 DiCoatanzo (1951)1 Clear Lake, ta, 61 107 142 157 198 208 Houaer and Bros11 (1963) 1 Oklahoma 81 127 152 175 18S Schof fman (1959) Reelfoot 'Ulke, Ten.a, 137 165 185 196 224 LaFaunce et al, (1964) 2 Sutherland Reservoir, Calif, 59 138 193 Present Study2 Conowingo Pond, Pa. 69 138 176 198 203 214 l Total length 2 Fork lengths converted to tot4l lengths uaiog the ralat1onahlp TL-0.96 + 1,04 l"L 7.3-35

MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE PONO MUDDY CREEK PEACH BOTTOM ATOMIC POWER CREEK STATION STONEWALL POINT ** PEACH BOTTOM BEACH WILLIAMS TUNNEL STATE LINE ...

P_A,_.- - - - -

MD.

WILDCAT TUNNEL AVERAGE CATCH OF LARVAE PER 10 MIN TOW

• $. 0.49

• 0.50 - 0.99 GLEN COVE

• 1.00 - 4.99 41 5.00 - 9.99 fl 10.00 - 19.99

@ ~ 20.00 FIGilRE 7. 3. 3-1 Distribution of bluegill, Lepomis macrochirus larvae ( $_ 25 mm) at plankton net stations in Conowingo Pond, 1969-1973.

7.J-36

7.3.4 SPOTFIN SHINER (NO~fQE!§ §E112E~§fY§)

7.3.4.1 Food Habits Food habits were determined from a total of 392 stomachs which contained food collected in June through October, 1967-1968. The primary food in all months except July was

~l2QQ£~~ (Table 7.3.4-1). In July, aquatic insects and cladocerans were consumed in approximately equal proportions.

Terrestrial insects, copepods, chironomid larvae and other items formed a minor portion of the diet.

7.3.4.2 Reproduction The spotfin shiner lays adhesive eggs which are attached to the undersides of branches and logs. It spawns from early June to late August in the Pond. carlander (1969, p. 431) reported that both sexes mature at age I though some individuals may not spawn until age II and he reported spawning to occur from early June until late August in New York. It spawns in late July and August in Iowa and early June in Maryland.

The presence of young fry in the seine catch indicates that spawning may occur from late May to' late August in the Pond.

Plankton net samples also indicate that it spawns from late May~

through August. The larvae are distributed throughout the Pond and no specific spawning sites were noted (Figure 7.3.4-1). It spawns over a temperature range of 51 to 83 F; the peak occurs at 65 to 82 F (Figure 7.3.1-2).

Its fecundity in the Pond was determined from 31 specimens collected in the preoperational period and 37 specimens collected in the postoperational period. The fecundity ranged from 260 to 1,658 (average 610) in the preoperational and from 104 to 1,594 (average 715) in the postoperational period. No statistical differences (P>0.05) were discernible between the two periods.

7.3.4.3 Age and Growth A total of 343 specimens of the spotfin shiner collected in 1966 was aged. Most were O+ and one year old. No specimens older than age three_ were collected. __ Th~ age I _f_~sh attained an average size of 62 mm; at age II the mean length was 75 mm.

0 ~~-

The time of annulus formation was determined from 52 fish collected in January through July 1967. An annulus was present on scales of those fish collected after 5 May. Growth resumed at a water temperature of about 60 F.

7.3-37

Tt\BT,F. 7.) .ti.-1 Food composition of the spotfin shiner, Notropis spilopterus expressed as estimated percentage volU111e and percentage frequency of occurrence (in parentheses), collected from Conowingo rond June through Octob~r 1967-68.

Month Jun Jul Aug Sep Oct No. St01114chs 76 79 90 64 84 Food Group Cladocera 56 (91) 39 (64) 57 (79) 66 (84) 78 (93)

Copepoda tr (5) l (1) 1 (6) tr (22) l (10)

Chironomid larvae 2 (14) 1 (13) J (14) 2 (19) l (6)

Aquatic Insecta 39 (70) 43 (71) 24 (41) 26 (53) 10 (33)

Tet'l.'estrial Insecta 2 (8) 10 (24) 3 (7) s (20) tr (1)

Miscellaneous* l (25) 4 (40) ll (68) l (31) 1l (34)

• Miscellaneous includes Nematoda, Bryozoa, Oligochaeca, Ostracoda, Amphipoda, Hydracarina, fish scales, detritus, algae, plant matter and unidentified eggs.

7.3-39

MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE POND MUDDY CREEK PEACH BOTTOM ATOMIC POWER STATION STONEWALL POlNT , PEACH BOTTOM BEACH WILLIAMS TUNNEL STATE LINE*P_A,_.- - - - -

MD.

AVERAGE CATCH OF LARVAE PER 10 MIN TOW

~. * '5. 0.49

'

• 0.50 - 0.99

• 1.00 - 4.99 GLEN COVE

• s.oo - 9.99

~ 10.00 - 19.99 T

8 ~ 20.00 FIGURE 7. 3 .4-1 Distribution of spotfin shiner, Notropis spilopterus larvae (-:;. 25 mm) at plankton net stations in Conowingo Pond, 1969-1973

• 7.3.5 BLUNTNOSE MINNOW CF!m~2h~l~2 n2£~~~§)

The bluntnose minnow ranked third in seine catches in the Pond. Few were taken by meter net,

• trawl or trap net. Its abundance in the seine catch was low (2.50 fish per collection) relative that of the most common species, the spotfin shiner (56.31 fish pe~ collection). It is most commonly taken in tributary streams entering the upper part of the Pond and between Holtwood Dam and the Muddy Run Pumped Storage Station. It is not expected that the biology of the bluntnose minnow will be affected ty operation of PBAPA because its distribution is limited to areas removed from the potential influence of thermal effluent. An extensive study of its biology in the Pond has not been conducted to date because it is not an important species.

7.3.5.1 Reproduction The bluntnose minnow male guards a nest in shallow water where the adhesive eggs are fastened on the undersides of sticks, boards, or stones (Breder and Rosen, 1966, p. 193 and Scott and Crossman, 1973, p. 478). Larvae were taken in the Pond in June and July. It spawns at temperatures of 75 to 82 F (Figure 7.3.1-2). Since the number of larvae taken was very low (0.01 fish per collection annually or less) the period of maximum spawning activity could not be determined.

7.3.6 The gizzard shad was accidently introduced into the Pond in June 1972 in the course of a study of the American shad being conducted by Philadelphia Electric Company. Information on the general biology of the species in the Pond is not available because relatively few gizzard shad were taken to date. It has reproduced in the Pond. The extent to which it will become established remains to be determined. Juvenile and adult gizzard shad have been most commonly taken by trap net, trawl and gill I

I. .

net in the Station discharge. Life history studies are under l way. Information presently available is on reproduction.

l ..

I 7.3.6.1 Reproduction The gizzard shad spawns in the late spring and summer; the non-adhesive, demersal eggs are scattered. Spawning begins in early June in Broad Creek. Most larvae have been taken in Broad Creek and along the east shore of the Pond (Table 7.3.1-1 and 7.3.1-2). Larvae are collected through August. It apparently prefers creeks or the mouth of creeks as a spawning area (Figure 7.3.6-1). It spawns over a temperature range of 68 to 84 F and peaks at 71 to 82 F (Figure 7.3.1-2).

7.3-41

MUDDY RUN RECREATION LAKE MUDDY RUN PUMPED STORAGE PONO MUDDY CREEK PEACH BOTTOM ATOMIC POWER CREEK STATION STONEWALL POINT PEACH BOTTOM BEACH

• WILLIAMS TUNNEL STATE LINE-P_A_.- - - - -

MD.

WILDCAT TUNNEL AVERAGE CATCH OF LARV A.E PER 10 MIN TOW

5. ---

y,

• < 0.49

• 0.50 - 0.99

• 1.00 - 4.99 GD 5.oo - 9.99 CD lo.co - 19.99 9 ~ 20.00 FIGURE 7. 3 .6-1 Distribution of gizzard shad, Dorosorna cepedianuro larvae (25 mm) at plankton net stations in Conowingo Pond, 1969-1973.

. ** ** ~ **. ;'- .. ~ ...... ~ ...":". ...-....-.....-.-......- *.-.

7.3.7

... ,,..,.. ,;.' ;_('.;:':' .*

. . . *~ ~ .' : f;.~.?_-. ~_*. *.~..-* ,*.',-.*

• 1'.:*,*.**.*.*..

• /'!{'.*' *.~..

7.3.7.1 Food Habits .;.'. .'1~* t(\.i~!*~ ,*.~~,-..*. :.*.~ .*. .:~*\ .** * :*.

..;:*..~~~~,::~~ *i.* ,. '.

Walleye (~50 mm) ate fishes and. cope pods . whi.~;;;.: ~~:~~9.~~-

• larger than 50 mm fed almost exclusively on fishes t-.stiqb'?as tessellated darter, white crappie, bluegill, pumpid;ris~e~d, walleye, channel catfish and minnows, Walleye less .than'.:':Joo.mm fed mostly on the tessellated darter. * . <':':*;.;'."~~-i*'<; :

• 7.3.7.2 Reproduction

. . >>: ~ ':../::.;t,:~<('.-~ * . .

The walleye scatters eggs in shallow areas with~:...:cl.ean rocky bottoms. Parsons (1972, p. 656) reported that those in Lake Erie had completed spawning by the end of April.

• Iri .*."the Pond, larvae were taken from April through May; maximal densities occurred in May. Most larvae were collected in the creeks. and coves in the southern portion of the Pond (Table 7.3.1-1 ." and 7.3.1-2).

Data on fecundity are not available because of the small population of walleye in the Pond. carlander (1945) cited by Eschemeyer (1950, p. 46) estimated that the walleye (343-556

• mm) in Lake of the woods, Minnesota produced 35,000 to 137,000 eggs.

Eschemeyer (1950, p. 47) reported that the walleye in Lake~-...

Gogebic, Michigan produced 36,871 to 154,906 eggs. Wolfert (1969, p. 1877) reported that the egg production of walleye in the eastern and western basins of Lake Erie ranged from 48,000 to 614,000.

Eschemeyer (1950, p. 24-25) reported that the spawning season began from mid-April to mid-May when the water temperatures ranged from 39 to 48 F and the peak occurred at 46-48 F. Calhoun (1966, p. 424) reported that spawning occurred at 63 F. but the "best temperatures" were between 45 and 50 F.

The walleye spawns at temperatures of 51 to 74 F in the Pond and the peak is at water temperatures of 57 to 68 F.

7.3.7.3 Age and Growth Most of the 99 specimens aged were less than four years.

The walleye attained a size of 122, 223, 333, 391, 439, 499, 510 and 514 mm at an age of I, II, III, IV, V, VI, VII, VIII and IX, respectively. Growth was best in the first three years. A comparison of the growth of the walleye in the Pond with that in other bodies of water shows that growth rates vary considerably (Table 7.3.7-1).

7.3-43

Comparison of growth rates of walleye, Stizostedion vi.treum, from various parts of the country.

Original measurements in inches converted to millimeters. Data from othllr studies repi:uduccd fi:<'m Calhoun (1966, p. l;:!**: a~d .::.-chc=:;cr (1950, p. 75),

Source Place Ase Grou2 I II Ill IV 'I VI VII VIII IX x Eachmeyer (1950)1 _ Laite Gogebic, Mi, 112 236 300 353 386 414 429 439 Rose (1950) 1 Spirit Lake, Ia. 183 282 366 445 505 564 602 632 Roseberry (1951) 1 Clayton Lake, Va. 251 386 503 589 663 701 759 818 Deason (1933)1 Lake Erie 107 213 287 376 457 528 Eddy and Carlander (1939)1 Minnesota Lakea 117 218 305 381 460 52.1 582 640 678 Carlander (1945)1 Lake of the Woods, Minn, 163 236 292 343 378 42.4 465 505 549 577 Stroud (1949)1 Norris Reservoir, Tenn. 262 417 475 sos 528 533 561 632 Kennedy (1949) 1 Lake Mat1itoba, Canada - 290 330 378 411 434 455 500 505 Forney (1965)1 Oneida Lake, N.Y. (Ma.le) 155 234 2.95 340 366 388 404 (Female) 160 241 307 358 394 424 447 Present Study2 Conowingo Pond, Pa, 122. 223 333 391 439 473 499 510 514 1 Total length 2 Fork length

\;,

-'**----------~-

7.3-44

t~ *

• 7.3.8 7.3.8.1 Food Habits The young of the largemouth bass (11-80 mm) are mostly copepods and cladocerans. Fishes and cladocerans were the most important food item of bass greater than 60 mm. The largest bass examined was 195 mm.

7.3.8.2 Reproduction The largemouth bass builds a nest on a variety of bottom types (Calhoun 1966, p. 340). It spawns in the spring and summer, somewhat later than the srnallmouth bass. Few larvae were taken in conowingo Pond, mostly at locations along the east shore (Table 7.3.1-1) from June through July. Spawning occurs over a temperature range of 62 to 81 F (Figure 7.3.1-2). Peak spawning occurs between 66 and 73 F. Suitable spawning temperatures have i'

been variously reported between 60 to 75 F (Calhoun, 1966, p.

r I 340). The eggs hatch in 2 days at 72 F and 5 days at 66 F.

I

'I ,

!i 7.3.8.3 Age and Growth Most of the 81 bass aged were less than four years.

Much of the growth (62%) occurred in the first three years. The growth rates vary considerably between different bodies of waters (Table 7.3.8-1).

In Lake George, Minnesota (Kramer and Smith, 1962, p.

37) rates of embryo development, sac fry growth, and fingerling growth during the first four weeks were directly related to mean daily water temperature. Strawn (1961) cited by Calhoun (1966,

p. 339) reported that the fry growth was slower at 90.5 F.

However, the growth was positively correlated with temperature to at least 81.5 F. Maximum growth occurred at temperatures of 81.5 and 86 F.

7.3-45

@fiA~bi'. 'N'wtmttrMbW't *

'TA!'LP. 7. ~.S-l

,\ c.:tt'l('.nla..,n ol gr,1wth rotos C1f targctr.outh bus, Mlcrn1,te~ ~. in varloua parts o( the C'Ountty. b~u fcurn oc.hcr  :& tuJle$

t"cproJuctd (rJo C.>.Lhoun (l 1J66, P* JJftt. Octntn.tl 1J.::a ... lu.*,~1v:u.:1 4u 'o.,;hce \;1Jnv~no1'1 lo,) "'tlU:itct\!'C'.:i*

At o Crou A,!19; Cr0\12:

S::i\lr.:o ttla.:'1 II Ill lV v VI Vt! Vlll tlt x XI XU XllI XIV 'I:'/

MrAl (1964)1 Urown 1 1 Lako., Wla. 86 161 231 282 318 353 396 Cooper And SchAfer (1954)1 llhl tmro L1ke, l\lch. 169 24l 2?7 333 H6 391 419 4SS 457 478 Roec:h and Patton (1948) l take Vnuvlua, Ohio 89 178 249 297 356 391 417 457 f.**** (1950) l Ohio b9 17~ 257 ll8 368 407 1,so 480 503 Eddy and Carlandcr (193?)2 Hlnneaot4 91 113 257 307 HS 399 429 439 493 sos McC*ta *r

....... (1937) t ttulloQ W1tconet1n Quabbin Raservolr, 8~ 18& 267 JI& 3)6 417

)di~

445 414 442 460 475 49' H3 523 533 Th~!!!~~

~.:ISfto 102 234 325 381 467 478 439 (1966)2 Folacm L:lke 1 CaUf. 1~2 264 32.5 368 '~l 432 htr1uch1 (1~5))1 L.ak* Wapp.>>ipaUo, l{o, 137 277 33d 409 460 49a t.aF'aunca ct al. SuthGrl4nJ ll.:*arvolr, (1964)2 Calif. l6S 290 363 414 460 Sonnott (1?3711 Scro~d (1948)

Loulllona

fot'rit l..ike, tenft.

1~3 175 287 JU 36~

373 478

.,)9 ,,,.,

531 ,97 490 630 s:a 658 688 706 719 Pres\tnt Study* Concvtnao Pond, Pa. 129 219 29~ 341 372 404 418 429 450 467 477

.l

• Total hngth 2

• York length l'lr!*3lnCll r:u:asure=cu\U il\ Jor\c. lcnittn converted co coed hnach ~7 the tollovt*s rd4donohlp: *n. ~ 1.011

• 1.034 I'!.

7.J-46

7.3.9 7.3.9.1 Food Habits Small bass (21-81 mm) ate mostly chironomids, other aquatic insects and fishes. Larger bass (>BO-mm) fed mostly on cladocerans and fishes. The largest bass examined was 149 mm.

Similar habits were observed in the preoperational period.

7.3.9.2 Reproduction The small mouth bass builds a nest in a shallow area with a gravel or rock bottom. It spawns 'in the spring and early summer. Larvae were collected from May through July, but in low numbers. Most of larvae were taken along the east shore of the Pond (Table 7.3.1-1 and 7.3.1-2). The smallmouth spawns at temperatures from 61 to 82 F (Figure 7.3.1-2). The peak of spawning occurs at a temperature of 68 to 77 F. Other investigators (see Calhoun, 1966, p. 359) report that spawning occurs over a temperature range of 55 to 70 F.

The developmental period appears to vary with temperature. Sigler (1959) cited by Calhoun reported that smallmouth bass eggs hatch in 9 1/2 days at 55 F and 2 1/2 days at 78 F. Webster (1948, p. 43) found that incubation required 10 days at 55 F and 2 1/4 days at 75 F. He also reported, based on'"""

laboratory studies, that the developing ova survived a temperature rise from 53 to 77 F. Eggs developing at 65 F transferred to 50 and 75 F were not adversely affected.

Too few smallmouth bass were caught to estimate fecundity. Calhoun (1966, p. 360) in a review of fecundity reported that egg production varies from 2,000 to 20,825 eggs per female depending on age, length and weight.

7.3.9.3 Age and Growth Although the smallmouth bass attains an age of nine years, most were less than four years. Most growth (57%)

occurred in the first four years. A comparison of the growth rates in different waters showed considerable differences throu~hout the country (Table 7.3.9-1).

Growth rates in Lake Huron were positively correlated with surface water temperatures, more growth occurs in warmer waters (Coble, 1967, p. 87). Latta (1963) cited by coble also found positive relationship between growth and temperature in Lake Michigan.

7.3-47

TABLE 7.).9-l A comparison of calculated growth rates of small1110uth bass, Microptet"Us dolomieui in various parts of the country. Original measurements in inches converted to millimeters.

Data from other studies reproduced from Calhoun (1966, p. 357).

Source Place Age Groul?

I II III IV v VI VII VIII IX x XI XII Latta (1963)1 Lake Michigan 99 160 206 246 292 335 371 401 427 442 4SS 447

- ~- Tate (1949)1 Iowa atreama 94 145 198 249 297 356 391 417 Patriarche and Lawry (1953)1 Black River, Mo. 68 157 236 302 366 406 Doan (1938)2 Lake Erie 165 206 246 284 315 348 373 Bennett (1938)1 lliaconsin 61 145 224 290 340 376 404 429 455 462 475 soo Peek (1965)3 Ark.tnsae River, Ark. 79 156 225 296 375 463 547 619 Thorpe (1942) 1 Connecticut 102 183 241 290 333 371 401 429 Smith and Moe (1944)1 Minnesota 99 185 277 310 462 521 Stroud (1948)1 Norris Reservoir, tenn. 117 259 358 411 445 457 472 Webster (1954)1 Cayuga Lske, N.Y. 165 213 262 307 348 373 396 424 432 457 Watson (1955)1 Big Lake, Maine 76 147 218 279 330 376 409 434 l'resent Study* Conowingo Pond ,

Pa. 98 175 228 275 328 395 432 480 485

. l Total length

... 2 3

Fork length Standard length

~~~*

,. . Original measurements in fork length converted to total length using the relationship:

• FL* 0,26 +.1.06 FL t

- - - ---------- --~----

..~ : .

~

7.3-48

7.3.10 MOVEMENT OF FISHES .--..

7.3.10.1 Movement of Fishes in Conowingo Pond An analysis of 1,119 recaptures of 15,493 white crappie tagged between 1966 and 1973 (preoperational period) showed that r it moves seasonally within the Pond. In late April and early May l it generally moved upstream. Those tagged in the upper portion of the Pond in the vicinity of the Muddy Run Pumped Storage Station in May usually had moved downstream to the south of Peach Bottom by late June. Movement in the summer has been difficult to assess because few crappie were recaptured in July and August.

In winter, it congregates at the mouth of creeks in the lower part of the Pond.

The channel catfish does not move extensively within the Pond. Most of 357 recaptures from 5,496 fish tagged were from the locality at which they were originally tagged. This includes some recaptured from two to five years after release.

7.3.10.2 Movement of Fishes in the Plume Fishes were tagged to determine their movement in and outside the thermal plume in the period July 1974 through March 1975. Some 332 channel catfish, 386 white crappie and 64 brown bullhead were captured, tagged and released in the plume.

A total of 28 channel catfish (8.43), 71 white crappie (18.43) and 12 brown bullhead (18.8%) was recaptured. All of the brown bullhead were recaptured in the plume, indicating no/or little movement. One bullhead was recaptured six times. All but one channel catfish was recaptured in the plume; which was recaptured in Broad Creek, (about four miles downstream). The recaptures indicate that the channel catfish may remain in the plume.

Twenty recaptures of the white crappie were made in July through December 1974. All but one of the recaptures was made in the plume. The single specimen tagged in November was recaptured at Broad Creek in December.

In January through March 1973 some 51 crappie were recaptured. Three were recaptured by anglers in Broad Creek.

Only 7 of 51 recaptures were from the plume: one each in January and February and 5 in March. A total of 39 was recaptured at Broad Creek and one at Conowingo creek by anglers; 30 were recaptured in Broad Creek in January. Those recaptured in Conowingo and Broad creeks in early January 1975 were tagged in the plume in November and early December.

7.3-4-9

The movement to Broad Creek may have been related to a complete shutdown of PBAPS between 17 and 26 January. Of the 30 recaptures, 9 were made before PBAPS shutdown and 21 were made between the period 18 through 31 January. The sudden increase in recaptures in the latter period suggests that in the absence of the heated plume, the species resumed its normal pattern of movement. After PBAPS came back on line, no increase in rate of recaptures occurred in the plume. This suggests that the crappie did not move back into the plume perhaps because it did not contact a temperature gradient which would stimulate such a movement. Movement to the lower portion of the Pond (Broad and conowingo creeks) in winter is not unusual. Most of the recaptures in the winter of fish tagged in the preoperational period was from the lower portion of the Pond.

7.3.ll NATURAL MORTALITIES OF FISHES IN CONOWINGO POND substant*ial natural mortalities, particularly of the channel catfish, have been observed in late May and June since 1966 in conowingo Pond. Relatively small numbers of carp, quillback sucker, white catfish, brown bullhead, eel, bluegill, pumpkinseed, largemouth bass, white crappie and walleye were seen (Table 7.3.11-1).

The exact cause of these mortalities is not known.

However, live but sickly channel catfish taken from the Pond in the early summer of 1968 were examined at the Pennsylvania Fish commission, Benner Springs Fish Research Station, Bellefonte, Pennsylvania where ~gromQn5!§. spp. was identified as an infecting

• ~ organism. outbreaks of ~~~mons2 are not uncommon among

(:

>;.;.: warmwater fish populations and usually occur in the spring. None If of the mortalities could be traced to the operation of PBAPS.

' . *.~... ;

-~ ..

7.3-50

~ .

i\ "

i *.'

f i*

I  !*;.*:

TABLE 7.J.11-1 . :<.: *}&*~ :f~**** ~

r* Species composition of dead fishes observed in January-December *;./.\ '.~*i;:V~s :;:}*:: . :*

• during the preoperational (1966-1973) and postoperational (1974) ;.;>>:..:iv~T~~f';{~Qt( , ~.

• periods in conowingo Pond. * * .:; *'?'.;::'~~;f~1Wf:~~L~:: . *: .

Year 1966 1967 1968 1969 1970 1971 Species . .>>!:'.!f/~:.'.!~~'.: **.~: *...

,[. gairdneri Q. carpio N. crysoleucas 3 2 1

1 13 2

6 4Q*'~;J~}f li* hudsonius 2

!'.!.* spilopterus 1

,[. atromaculatus 1 - ... '1t* - ..

Q. cyprinus 4 - ....... :.:2 Q. commersoni 1 3 12

!:'.!* macrolepidotum 1 Ictalurus spp. 107+ 310+ 16 45 303

!*~ 2 2

~* nebulosus 2 2 7 1* punctatus 274+ 89 494 15 53 814+ 62 88 333 A* rupestl:is 3 L. auritus 1 1 1 1.* gibbosus 1 6 2 1.* macrochirus 1 1 4 3 5 Micropterus sp. 1 l l

!:'.!* dolomieui 1 2 1 1 1

!1* salmoides l 3 f.. annularis 2 4 10 111 123 667 21 57 187 f

• nigromaculatus 1 g_. olmstedi 1 R_. £laves cens 1 1

s. vitreum 2 150 3 l Unidentifiable 15 53 171 2 Total 405+ 462+ 524 130 380 1999+ 92 190 633 7.3-51

...* 7.3.12 RECREATIONAL FISHERY Plosila (1961, p. 70-76) censused the anglers at conowingo Pond in the spring through fall in 1958 to 1960. He reported that crappie (mostly white) comprised 48 to 55% and catfishes (channel. white, brown and yellow bullhead) constituted 27 to 37% of the catch. sunfishes (bluegill, pumpkinseed, rock bass, green and redbreast) constituted 6 to 163 of the catch.

The smallmouth bass, largemouth bass, yellow per.ch and walleye .

l. contributed little. He concluded that "the size of the white crappie population has the greatest influence of any fish on the average catch per effort and the resulting harvest by fishermen from Conowingo Lake". He also observed seasonality in fishing.

A substantial number of crappie and other sunfishes was caught in .

spring and fall but few were caught in summer. The catch of catfishes was uniform throughout the period of study. No definite seasonal trend was evident for~the catch- o:E--- smallmouth and largemouth bass. our observations of angling, along with many personal contacts with anglers since 1966, indicate no I

substantial change in the nature of the fishery.

Most fishing is done from small boats or along shore at a limited number of access points such as railroad culverts along the east shore. Limitations on access for boat fishing are imposed along the east shore by the presence of the Pennsylvania Railroad Lj,ne and on the we.st shore by scarcity of access roads.

Our survey determined the extent of the fishery in winter, (January through March, 1973 (Euston, et al., 1974, p.

4-75 to 4-79) and 1974) which was a period not studied by Plosila, in the Pond. our earlier observations indicated that fishing occurred primarily in Maryland waters at Conowingo and Broad creeks and Funks Run. Consequently, these areas were surveyed intensively although other areas were visited regularly.

No fishery existed in other areas.

Anglers caught 15 species (Table 7.3.12-1). The largest number (13) was taken in March 1973 when fishing was done from the shoreline. In January and February, when on occasion fishing was done through the ice, 4 to 5 species were caught. The white crappie was most common and comprised at least 99% of the catch in January and February. In March the catch of crappie was 65 (1974) to 81% (1973). The bluegill was the next most important

• ~~~~~species, moat _were_taken_in Ma~ch.--"'-.-~~~~~~~--~~

The length-frequency distribution of the white crappie in the angler catch indicated that those less than 170 rrun fork length were usually released.

The fishing pressure varied from January to March and on weekdays and weekend days. Generally, the fishing pressure was 7.3-53

greater on weekend days. Total estimated fishing pressure was greatest in March and least in February. The highest catch per hour was observed in February (4.18) and the lowest in March (2.21).

7.3-54

TA!LE 7.).12-1 Speclet compoa1t1oa of flab** caught 117. t:lte. angler* dudo.g the via.ter creel ceMu* of Conovtngo Pond, .J*nu*t7*Ha.rch 1973 &lld 1974.

Tear 1973 1 74 Hoath JaG Feb l!&r Total Jon Feb Kar Total llo.

" llo.

" Ho.

" No.

" Ho.

" Ho.

" Ho,

" Ho, Specs.ea llh1te crappie 1829 99,2 2290 98,8 1958 81,0 6on 9Z,4 1771 99.7 1177 99,7 182 65.0 3UO '6.7 Blue1111 12 o.t u o.5 3SS 15.9 409 6.2 z 0.1 0.1 ~3 u.a 36 1.1 Pumpk1oned 4 o.z 4 0.1 Black crappie 0.1 13 0,6 l 0.1 17 o.3 tr 0.1 0.1

-.J Small-.tll ban tr tr 0.1 l 0,4 1 o.t w Larguouth baaa 1 o,t tr 10 0.4 1Z o.z 29 10.4 29 0,9 I

\1\ Tellov perch tr z 0.1 tr o.4 tr

\1\

Qiana.el catfiah 11 o.s 11 0.2 tr 23 a.2 24 0.7 Tdlov bullhead tr tr 3 l.l 0.1 Brovn bullhead 29 1,2 29 0.4 0.4 0.1 l,4

<:erp Whit* aucker 0.1 tr 2 0.7 0.2 0.1 Coldn ehlner 2 0.1 tr C1ccar4 ahad l tr tr ltovtl ttout o.4 tr Total 1843 2317 2417 6577 1776 1180 180 3236 tr

• Le.11 thu O.l

) )

7.4.0

..J' TEMPERATURE EXPERIMENTS WITH FISHES The methods and results of thermal studies conducted from November 1972 through December 1974 have been reported in Robbins and Mathur (1974a, b and 1975a,b; Section 5). The studies were designed to provide predictive data on (1) the behavior of fishes in or near the thermal plume and (2) the effect of changes in temperature in or near the plume which may occur as a result of PBAPS operation. The experimental temperatures used were the temperatures predicted a~ the jet discharge (13 to 17.5 F increase) by Elder at al., (1973).

Studies were also conducted with a temperature increase of up to 35 F to determine upper temperature tolerance limit.

Acclimation in fishes is more rapid with an increase than with a decrease in temperature. Fishes captured when the field temperatures are falling (mid-july through mid-February) may respond differently to temperatur9 changes than they do when field temperatures are rising (mid~February through mid-July) even though they are captured at the same ambient te~p~rature.

The major experimental fishes were those most commonly taken in the Pond. They include the spotf in shiner, channel catfish, pumpkinseed, bluegill and white crappie. Fewer data are available for the bluntnose minnow, gizzard shad, largemouth bass, smallmouth bass and walleye and are reported below.

7.4.1 TEMPERATURE PREFERENCE Two phenomena are associated with temperature preferences, low thermal responsiveness (LTR) and multimodal preference response (MPR). Meldrim and Gift (1971, p. 10) defined LTR as the inability of a fish to avoid areas in a thermal gradient which produce stressful conditions. They defined MPR as a selection of two or more pref erred tempera~ures within a test.

Data for rising and falling field temperatures for the spotfin shiner, channel catfish, pumpkinseed, bluegill and white crappie were analyzed separately by a stepwise multiple regression to determine the relationship between the preferred temperature (Y), acclimation temperature (X1) and mean total length of fish (X2). Sufficient data were not available to conduct this analyses for other species. In calcula~ing the regressions, the median preferred temperature was used when fish preferred a range of temperatures. If more than one temperature was pref erred by the fish (MPR) each selected temperature was used with the number of fish which preferred tnat temperature.

In all cases the acclimation temperature accounted for most of the variation in the preference temperature (Table 7.4.1-1). The 95% confidence limits on the population mean of the preferred 7.4-1

temperatures were computed (Figures 7.4.1-1 to 7.4.1-5) using the equations given in Table 7.4.1-1, and compared with results from the temperature shock and avoidance studies.

7.4.1.1 Spotf in shiner 7.4.1.1.1 Falling Field Temperatures The highest temperature preferred was 86 F by fish acclimated from 79 to 82 F in July 1973. The lowest temperature selected was 50 F by fish acclimated to 43 F in mid-January 1974.

Spotfin shiner pref erred a temperature which averaged 9 F above acclimation. The difference between acclimation and preferred temperature was little at high acclimation temperatures but increased as acclimation temperatures decreased. This trend was true for most species studied. LTR was displayed in 12 of 46 tests.

7.4.1.1.2 Rising Field Temperatures The lowest temperature preferred was 54 F by fish acclimated to 38 and 39 F in late February and early March 1974.

The highest temperature selected was 88 F by fish acclimated to 82 F in early July 1974. Fish preferred an average of 11 F above acclimation. No LTR was displayed during this period.

7.4.1.2 Channel catfish 7.4.1.2.1 Falling Field Temperatures The highest temperature preferred was 95 F by fish acclimated to 80 and 71 F in late July and mid-September 1973,

! . respectively. The lowest temperature selected was 52 F by fish acclimated to 35 F in mid-January 1974. Channel catfish preferred an average of 13 F above acclimation. LTR and MPR were i'

>* each observed in 4 of 21 tests.

~*

7.4.1.2.2 Rising Field Temperatures The lowest temperature preferred was 55 F by fish

~

I. acclimated to 42 and 44 F in late March 1974. The highest r*.**

• . temperature selected was 95 F by fish acclimated to 85 F in

' mid-July 1973. Channel catfish preferred an average of 12 F above acclimation. LTR was observed in J - of 21 tests.

7.4.1.3 Pumpkinseed 7.4.1.3.1 Falling Field Temperatures The highest temperature preferred was 91 F by fish acclimated to 78 F in mid-September 1973. The lowest temperature 7.4-2

~... . *1: .

selected was 50 F by fish acclimated to 47 F in late November..-...

. .:*,. 1973. Fish preferred an average of 6 F above acclimation.* . LTR was displayed in 6 of B tests at acclimation temperatures . of 68 F or below. LTR was r.ot displayed at acclimation temperatures above 68 F MPR was displayed in one test.

~ .....

7.4.1.3.2 Rising Field Temperatures The lowest temperature pref erred was 70 F by fish acclimated to 67 f in late May 1974. The highest temperature selected was 88 F by fish acclimated to 76 F in mid-June 1974.

These fish preferred an average of 9 F above acclimation. LTR was observed in 1 of 10 tests.

Bluegill Falling Field Temperatures The highest temperature preferred was 90 F by fish acclimated to 79 F in late August 1973. The lowest temperature selected was 64 F by fish acclimated to 46 F in mid-November 1973. Bluegill preferred an average of 14 F above acclimation.

LTR was displayed in 9 of 13 tests at acclimation temperatures of 68 F and below. LTR was not displayed at temperatures above 68 F.

7.4.1.4.2 Rising Field Temperatures The lowest temperature preferred was 61 F by fish acclimated to 38 F in mid-February 1974. The highest temperature selected was 88 F by fish acclimated to 78 and 83 F in late June and early July 1974, respectively. Fish preferred an average of 11 F above acclimation. LTR was observed in 3 of 1q tests, only at acclimation temperatures less than 68 F.

7.4.1.5 White crappie 7.4.1.5.1 Falling Field Temperatures The highest temperature preferred was 82 F by fish acclimated to 79 and 80 F in late July 1974 and late August 1973, respectively. The lowest temperature selected was q5 F by fish acclimated to 37 F in mid-January 1974. Fish preferred and average of 8 F above acclimation. LTR was observed in two tests and MPR was observed in one test.

7.4.1.5.2 Rising Field Temperatures The lowest temperature preferred was 50 F by fish acclimated to 41 and 43 F in early March and April 1974, respectively. The highest temperature selected was 79 F by fish 7.4-3

acclimated to 76 F in late June 1974. Fish preferred an average of 3 F above acclimation.

7.4.1.6 Other Species Temperature preference data for other selected representative species are presented in Table 7.4.1-2. Data are not available for the gizzard shad. Bluntnose minnow acclimated at 33 to 68 F preferred 41 to 70 F. LTR was observed in one of eleven tests. smallmouth bass acclimated at 54 to 82 F preferred 73 to 90 F. Largemouth bass acclimated at 38 to 82 F preferred 63 to 90 F. LTR was observed in 8 of 23 tests. Walleye acclimated at 50 to 52 F preferred 59 to 63 F.

--- - - ~-- --- - - --

. 7.4-4 I

t.

i.

k

• ~ '

.. UeLE 7.4.1-1 Reg\"eu!.on equations of the preferred temperature ('l), acclirn&tlon temperatun (Xl) and aiean totnl length (X2 ) fo\" tha spotftn shine\", channel catfish, pumpkinseed, blu~gUl and wh ta crappie ~or falU.ng and rt.sing f1illd tempuuturea , Data front tests conducted bct1o1ec11 March 1973 and Dece?lllbe\" 1974.

AccU11111ti.on Hean Order of Entry Temperature Total Longtl\ of tndependent Regresston Species Range (F) Range (111111) variables Equation N R2 s y.x l'ALLING FIELD TEMPERATURES Spotfin shiner 34-82 39-81 Ace lim. Temp. y. 27.837 + o.696 x1 152 0.832 4.680 Total Length y

• 32.929 + 0.111 x1 - o.098 x2 152 0.847 4.484 Channel catfi.811 35-82 56-216 AccU111. Terap. y

• 39.129 + 0.596 x 80 0.710 5.912 Total Length y. 38.170 + o.598 xi + 0.005 x2 80 o. 711 5.945 Pumpktnaeed 47-81 51-82 Ace 11111. Tamp. y

• 11.460 + o.931 x1 38 0 . 666 7. 721 Total Length y a 25.116 + 0. 909 xl

• 0.197 x2 38 0 . 61l6 7.593 lllueglll 46-82 32-85 Ace Lim. Temp, YD 52.068 + 0,437 Xl 52 0.71!5 3.171 Total Length y

• 73.723 + o.314 x 1

• o.233 x2 52 0.877 2.426 Wh i.te c rapp le 37-80 91-144 Ace 11111. Temp. y

• 2.0.115 + 0.797 K1 J1 0.817 4.966 Total Length y ~ 32..916 + 0.847 x 1 - 0.141 X-i 31 0.843 4.675 RISING Ftl!LD TEMI'ERATURES Spotftn shlnor 38-82 38-83 Ace ll11t. Temp. Y~ 29,213 + 0,681 Kl 124 0.949 2.234 Tatal Lelll!th Y* 25.484 + O.b89 XJ: + 0.056 x2 124 o.~56 2.0H9 ~

Channel eatH.st\ 37 -86 84-252 /Ice 11111. Tel!IJI. y

• 30.515 + o.695 x1 74 0,806 4.906 Total Length y ~ 49.840 + 0.609 x1 - 0.075 x2 74 0.892 3.685 Pumpktnseed 52-83 63-101 Ace ltlll. Teaip. y ~ 48.695 + 0.413 K1 44 0.536 3. 789 Total Length y .. '*3.825 + 0,35!1 x1 + 0.104 ~ 44 0.573 3.677 Bluegill 38-83 42.-103 Ace llm, Taaip, y 3 36 .364 + o.606 x1 51 0.885 2.801 Total Lengtl\ ~ .. 37.986 + 0,613 x1 - 0.030 x2 51 0.8'30 2.77l 1111 ite erapple 41-79 96-165 Aeel!.111, Temp , y 2 26.113 + o.615 x1 48 0.681 5.231 Total Length y. 12.308 + o .407 x 1 + 0.218 x2 48 0.809 4.089 7.4-5

1'1\1:\LE ?.l1.* l-2 Su:nr.mry of cernperaturc preference data on other <111lccted representative spcctcs, All tc,;ts wore conducted at aaturatt>d o:<ygen lcvt!ls, nt a light level of 40 ioot*candlea, and at a pit of 7 .3 to 8. L.

t~o. Fish Sizu Rilnge Hean 'CL Accli.m.ation £'refo>rrcd Low The rmn l Species Date Pi.t l'est {"CL 1JU1!) (nWl) Te111pcrnture 'temperature llc~ponsive*

(11) (~') ncss Shown ..

?6 Sep 1973 1. 57-60 61 68 70 No 23 Oct 1973 55*73 65 62 63 No 7 ~'clb 1975 1, 49.53 5l 44 52 ~:o 17 J;;in 19711 4 110*44 4J 42 41*52 No 19 Dec 1973 1, 47.53 50 31, 54 No 14 F<!b 1975 4 49.55 51 34 50 i>o 30 Jan 1975 4 S2*54 53 33 !18-52 ~lo 5 Nat 1975 4 B-54 54 41 55-57 No 2 l Mar 1975 4 65*71 67 42 66 No 27 ~lar 197 5 4 85-92 88 42 59-61 tlo 10 Mac 1975 4 52-54 SJ 45 613 '/cg llorosomn ccpedianum JO Oct 73 4 132*144 137 56 :rone ~In MLcr_Qj!!£!!!_:! r!olonil.cuL 23 Jul 74 4 61*69 64 82 90 No l Aug 73 4 62-7l 65 81 None Yes 20 Jul 73 4 51-60 54 80 88*90 No 25 Ju11 74 J 83-102 ~2 77 86*90 ~lo 24 So!p 74 4 86-94 90 70 73*77 ~:o l<J Oct 74 4 125-134 128 63 ~lone No 24 Oct 74 4 lll

• 152 140 S4 70-73 Yu*

Hictopterus salmoidcs 10 Jut 74 4 54-58 56 82 88 No 23 Jul 7!1 4 63-73 68 82 88 No 31 Jul 73 4 52*64 58 61 8a !lio 30 Aug 73 4 96-103 99 Bl 90-91 No to Aug 73 4 56*68 63 80 86 No 86 29 Aug 73 31 Aug 7l 4

124-t49 65-76 137 70 79 79 88*90 Yes Uo l Aug 74 4 54*61 57 79 None No 15 Aug 74 4 65-88 82 79 llonc No 11 Sep 7J 4 71-89 78 7l 82*84 No 29 Oct 74 2 75* 112 94 54 Nona No 3 Jan 71. '.l 85-ll4 106 41 NonB Yes 22 Jlln 74 3 103*120 L13 41  :-;one Yes

! 15 Jnn 75 2 85* l28 106 41 tlona Yes 19 Feb 74 3 80* 121 106 38 None No 6 M.1r 75 2 134-142 138 41 Nono Yes 26 Mar 74 2 78*95 BG 43 63*G6 'fr!S r."

1 29 Mar 7l 26 Apr 74 2

3 165-l'.12 98-126 17'.I 1D9 52 55 73 Nona Ho Yes l May 74 4 70-86 8t 64 77 Yes 20 Jun 74 4 36*38 38 76 ~one llo

__ 4 _ _ _ 50-62 s5 __.___._1a

-~--- --------~*

27 Jun...74_

5 Jul 7l 4 43*48 46 82 None M one llo t;o ---- -----

10 Oct 74 4 200*328 315 63 Nona Yes 14 1'ov 73 4 195-212 203 50 59-63  ?;o to Apr 74 3 192*210 202 48 Nona )lo 30 }!.a.r 7l 4 2S8*296 272 52 63 :O:o I~ .

f i

'. i; Thermal *tresM 9hown when fish moved into cxtrcmu temperatures (usually 20 to 30 F Erom acclimation) in a steep gradient, 7.4-6

7.4.2 TEMPERATURE AVOIDANCE Data for rising and falling field temperatures for the spotfin shiner, channel catfish, bluegill and white crappie wer'=

analyzed separately by a stepwise multiple regression to determine the relationship between the avoidance temperature (Y),

acclimation temperature {X1) and mean total length of the fish (X2). The 95% confidence limits on the population mean of the avoidance temperature were calculated using the equations given in Table 7.4.2-1. The confidence limits are shown along with results from temperature shock and preference studies (Figures 7.4.1-1 to 7.4.1-5).

7.4.2.1 Spotf in shiner 7.4.2.1.1 Falling Field Temperatures The highest avoidance temperature was 94 F by fish acclimated to 81 F in early August 1973. The lowest temperature avoided was 59 F by fish acclimated to 4.7 F in early February 1974. Fish avoided an average of 20 F above their acclimation temperature.

7.4.2.1.2 Rising Field Temperatures The lowest temperature * *avoided was 61 F by fish ~

acclimated to 54 F in late April 1974. The highest avoidance temperature was 93 F by fish acclimated to 83 F in mid-June 1974.

Fish avoided an average of 18 F above acclimation.

7.4.2.2 Channel catfish 7.4.2.2.1 Falling Field Temperatures The highest avoidance temperatures (97 and 98 F) occurred at acclimation temperatures of 71 and 81 F from late July to mid-September 1973. The lowest temperature avoided was 57 F by fish acclimated to 47 F in late January 1974. Fish avoided an average of 24 F above acclimation.

7.4.2.2.2 Rising Field Temperatures The lowest temperature avoided was 67 F by fish acclimated to 54 F in late April 1974. The highest avoidance was 94 F by fish acclimated to 62 F in early May 1974. Fish avoided an average of 27 F above their acclimation temperature.

7.4 - 7

The movement to Broad Creek may have been related to a complete shutdown of PBAPS between 17 and 26 January. Of the 30 recaptures, 9 were made before PBAPS shutdown and 21 were made between the period 18 through 31 January. The sudden increase in recaptures in the latter period suggests that in the absence of the heated plume, the species resumed its normal pattern of movement. After PBAPS came back on line, no increase in rate of recaptures occurred in the plume. This suggests that the crappie did not move back into the plume perhaps because it did not contact a temperature gradient which would stimulate such a movement. Movement to the lower portion of the Pond (Broad and conowingo Creeks) in winter is not unusual. Most of the recaptures in the winter of fish tagged in the preoperational period was from the lower portion of the Pond.

7 -. 3-.1*1- NATURAL MORTALITIES OF FISHES -IN -CONOWINGO PONO substantial natural mortalities, particularly of the channel catfish, have been observed in late May and June since 1966 in conowingo Pond. Relatively small numbers of carp, quillback sucker, white catfish, brown bullhead, eel, bluegill, pumpkinseed, largemouth bass, white crappie and walleye were seen (Table 7.3.11-1).

The exact cause of these mortalities is not known.

However, live but sickly channel catfish taken from the Pond in the early summer of 1968 were examined at the Pennsylvania Fish commission, Benner Springs Fish Research Station, Bellefonte, Pennsylvania where ~grom2n~ spp. was identified as an infecting organism. outbreaks of ~g~QD~§ are not uncommon warmwater fish populations and usually occur in the spring. None of the mortalities could be traced to the operation of PBAPS.

among I I 7.3-50

... ' .. ... ~ ** :**~.- ./ : ,., **, ' .

i.

/'

\

TABLE 7.3.11-1 ,111~1'*

Species composition of dead fishes observed in January-December* * *, ...,.'. ".".::'.. *: ..

• t during the preoperational (1966-1973) and postoperational (1974) .... .:;:*;]-'. :.,:*,

• t periods in conowingo Pond. * *: :*,::.r:f::'(::x;*: ..*.

i t

I Year Species

.§.. gairdneri .1 g_. carpio 3 2 1 13 6 40 *: 76 N. crysoleucas 1 2

!* hudsonius 2 li* spilopterus 1

~* atromaculatus 1 Q. cyprinus 4 2 g_. commersoni 1 3 12 tl* macrolepidotum 1 Ictalurus spp. 107+ 310+ 16 45 303

!* catus 2 2 I* nebulosus 2 2 7 1* punctatus 274+ 89 494 15 53 814+ 62 88 333 t::,. rupestris 3 1* auritus l 1 .1 1* gibbosus 1 6 2

.!!* macrochirus 1 1 4 3 5 Micropterus sp. 1 l 1 tl* dolornieui 1 2 1 1 1 M. salmoides

• 1 3

g_, annularis 2 4 10 111 123 667 21 57 187 P. nigromaculatus l

~* olmstedi 1 f.* flavescens 1 1

§_. vitreum 2 150 3 l Unidentifiable 15 53 171 2 Total 405+ 462+ 524 130 380 1999+ 92 190 633

7. 3-51

7.4.2.3 Pumpkinseed 7.4.2.3.1 Rising and Falling Field Temperatures The highest temperature avoided was 95 F by fish acclimated to 76 F in mid-June 1974. The lowest temperature avoided was 83 F by fish acclimated to 79 F in late August 1973. Pumpkin seed avoided an average of 16 F above acclimation.

Bluegill 7.4.2.4.1 Falling Field Temperatures The highest avoidance temperature was 97 F by fish acclimated to 81 F in early August 1973. Bluegill never avoided temperatures below ~ ao- F, even when acclimated as low as 40 F in late January 1974. Avoidance temperatures averaged 27 F above acclimation. In three of nine tests, fish acclimated to 40 and 46 F lost equilibrium or died prior to significant avoidance.

7.4.2.4.2 Rising Field Temperatures As with falling field temperatures, no fish avoided temperatures below 80 F, even when acclimated as low as 41 F, even when acclimated as low as 41 F in early April 1974. The highest avoidance was at 98 F by fish acclimated to 77 F in lat6 June 1974. Fish avoided an average of 26 F above acclimation.

7.4.2.5 White crappie 7.4.2.5.1 Falling Field Temperatures The highest avoidance temperature was 85 F by fish acclimated to 55 F in late October 1973. The lowest temperature avoided was 65 F by fish acclimated to 48 F in late November 1973. Fish avoided an average of 25 F above acclimation.

7.4.2.5.2 Rising Field Temperatures The lowest temperature avoided was 74 F by fish acclimated to 43 and 52 F in late March and mid-April 1974r respectively. The highest avoidance temperature was 92 F by fish acclimated to 82 F in early July 197q. Fish avoided an average

--*- of 23 F above - ac-ciimation.

7.4.2.6 Other Species Temperature avoidance data for other selected representative species are presented in Table 7.4.2-2. No

temperature avoidance data are available for gizzard shad and

,. walleye. Bluntnose minnow acclimated from 33 to 45 F avoided 49 to 69 F. Smallmouth bass acclimated at 70 to 81 F avoided 90 to 98 F. Largemouth bass acclimated to 70 to 82 F avoided 90 to 98 F.

7.4-8

Tl\<1LF. 7.u..?.-1 Regression equations of tno avoidance temperature (Y), acclilll'lctLon telll{Jerature (X ) and muan total length (X2 ) for tho spot fin sh lner, ch11n11el c11tf ish, bl11eglll and white crappie fo~ fall iug nn<I rising field temperatures. llaca from tests comluctcd bctwc~n July 197l and Deccmbar 19/4.

Ace Limat ion Hean Ord.ir of Entry Temperature Total Length of Independ=nt RnRresslon Specles Range (F) Range (men) Variables Equatlon N R2 g y *"

FALLING FI<:LD TEMPERATURES Spotftn shlncr 40-81 52-83 Ace llm. Tc!llp, y D 47,78& + 0,532 xl 74 0.6 1*5 6.421 Total Length y .. 38.924 + o.456 x1 + 0.205 x2 74 0.671 &.221!

Chllnnel catfish 34-81 50-23f, Ace ll.M. Temp . y .. 54.339 + o.499 x1 106 0.565 7.470 Tota 1 I.ength y

• 59.773 + 0.465 x1

• 0.023 x2 106 0.578 7.400 Bluegill 40-81 36-137 AccUM. 'temp. y"' 74.073 + 0.226 X1 81 0,41,3 3.677 T:Jtal Longth y .. 64.667 + 0.3L5 XL + 0.060 x 2 82 0.41!9 3.545 llhite crappie 45.55 100-127 Acclim. Temp. 'l - 27 .668 + 0.9J9 ~l' 62 0,320 5.052 Total t.;ni;th y .. *4.242 + O.'Jll .t + 0.2115 x 62 0.405 4. 767 1 2 RISING FtELD tEHPERATURES Spocfln *hlncr 31!-83 45-94 Ace 11111. 'temp

• Total Langth y

• 44.966 + o.526 x1 yo 46.946 + o.539 x 1 - 0.043 x2 131!

138 0.69~1 0.70) 4.865 4.856 cnanna 1 catfis lt 38-76 151-250 AcclL111, To!Dp. y

• S5.194 + 0.494 x 1 71! o.i.n 1).538 Tota 1 Length y

• 59.486 + o.sto x1 - 0.025 x 2 78 0.4)1! 6. 511 L llluesi ll 41-77 Sl-78 Aeel lM. Temp. Y

• 58.7DJ + 0,481 XL .32 0.81'>8 2. 743 Total Length Y .. 31.&22 + o.&37 x1 + 0.278 x2 32 0.904 2.369 White crappie 41-82 98-133 Ace llm. Temp. y "' 55,747 + o.449 x1 62 0.911 2.0!l2 Total Length y"' 38.l36 + o.330 x1 + o.t9B x 2 62 0.974 l.125 7.4-9

Su.'lllMry of temperature avol<lance data on other selcctl.ld rl.lpr.iso:intatt.ve spccil.ls. All teats were conducted at ~ilturated o:<ygen levels, nt a light level of 40 fout-cundlcs and at " ptt of 7,5 to 8, L, Si?.e Acclimation twoldance ResponsP.

No. Fhh Range Mean TL Temperature Temperature Significance Species Date Pur Test (TL 1111!1) (mm) (F) (F) Lnvel 7 Feb 75 4 53-58 - 56 - ~- .;2 P,05 4 50-58 54 44 62 P,025 25 Jan 74 3 40-50 44 40 49* u.t, avot.dane<:

J 36-56 45 40 49 e,o5 17 Feb 75 4 6l-72 67 31, 61 P.OOl 4 63-H 68 34 6t .P,001 29 Jan 75 4 48-64 57 33 64 P,001 4 49-58 53 33 64 P.OOl 5 Mar 75 4 46-56 50 41 69 P,025 4 47*56 53 41 69 P.OOL 20 Mar 75 4 50-54 53 112 68 P.Ol 4 49-56 52 42 68 l',OlS LO Mar 75 4 47-56 SJ 45 69 l'.001

!, 4~ *SI> 52 *,5 6'J .P,025 Mlcroptcrus d->lom1eu1 20 Aug 74 4 90-114 LOL 90 100 ~.001 4 74-112 89 90 100 P.01 31 Jul 73 4 54*65 60 SL 95 P.OOL 4 57-67 61 81 95 P.005 3l Jul 74 4 53*58 55 79 97 p,0::1 4 55-67 60 79 97 e.001 26 Jun 74 3 98*140 121 17 98 u.t, r. *10!.d~!1Ce 3 tl 7 -155 128 77 98 P.OOJ 25 Sep 74 4 88*1'.12 105 70 90 P.COL 4 99-117 108 70 90 P,Ol'l l:lisropteru* salmoldns Ll Jul 74 4 43-60 48 82 98 u, t. a1~id~:ice 4 44-60 50 ~2 98 P.001 24 Jul 73 4 50-55 52 80 90 P.OOL 4 48-56 53 80 90 P,001 l5 Aug 74 4 G0*64 62 80 95 P.001 4 54-62 59 80 95 P.001 30 Aug 73 4 80-90 80 79 92 P.OOL 4 73-91 BS 79 92 P,001 l Aug 74 3 57-63 61 79 96 P,01 3 53-68 60 79 96 P,005 26 Sep 74 4 78-108 92 70 93 P.01 4 81-112 96 70 93 P,001 7.4-10

7.4.3 TEMPERATURE SHOCK Rapid temperature increase and decrease tests were conducted. When mortalities occurred, the differences between the control and exp.erimental mortalities (attributed to thermal shock) were evaluated statistically (P =0.05) using the exact test designed for small samples (hypergeometric distribution) given by Owen (1962, p. 479). The results of temperature shock studies are plotted with the 95% confidence limits of preference and avoidance temperatures to illustrate the relationships between potential fo-,:; thermal shock and predicted behavior of fishes in or near the thermal plume (Figures 7.4.1-1 to 7.~.1-5).

7.4.3.1 Spotfin shiner Specimens acclimated at 34 to 90 F and rapidly subjected to an increased temperature of 8 to 25 F showed significant (P<.05) mortality or loss of equilibrium in only 4 of 26 tests (Figure 7.4.1-1). In three of the tests, nearly complete mortality (34 of 35 fish) was observed with specimens acclimated at 79 and 90 F and rapidly subjected to temperature increases of 1~ F and a F, respectively. These mortalities occurred because tne specimens were subjected to temperature increases which exceeded the upper limit of their avoidance temperature. In the fourth test, two of nine fish died when acclimated at 58 F and subjected to a rapid temperature increase of 13 F.

Rapid temperature decrease tests were conducted on

' specimens collected at 39 to 81 F. Fish in 26 tests subjected to I a temperature decrease of 5 to 21 F suffered no mortality.

Temporary loss of equilibrium was observed in one test (all ten i specimens) with a temperature decrease of 21 F. In another test, 1 of 10 fish lost equilibrium with a decrease of 15 F.

L 7.ij.J.2 Channel catfish Rapid temperature increase studies conducted with channel catfish acclimated at 32 to 90 F and subjected to an increase of 7 to 31 F showed significant mortalities in 10 of 36 tests but, in all tests except one, the elevated test temperatures exceeded the upper limit of the estimated avoidance temperature (Figure 7.4.1-2). In the exception, significant mortality occurred with fish acclimated at 32 F and subjected to an increase of 18 F. When the latter test conditions were repeated no mortality occurred. Temporary loss of equilibrium was usually observed when the temperature increase equalled or exceeded 24 F.

.,I

• Rapid temperature decrease studies were conducted on fish acclimated at 45 to 77 F. Specimens subjected to 7.4-11

temperature decreases of 7 to 20 F suffered no mortalities in 26 tests. Only 3 of 291 fish temporarily lost equilibrium.

7.4.3.3 Pumpkinseed Specimens acclimated at 34 to 90 F and subjected to temperature increases of 7 to 35 F showed significant mortalities in 6 of 19 tests (Figure 7.4.1-3). In all tests where mortality was observed the elevated test temperature exceeded 31 F or the upper limit of avoidance temperature (97 F}. No loss of equilibrium was observed where test temperature increases were less than 29 F or at an experimental temperature of 95 F.

Specimens collected at 55 to 81 F were subjected to temperature decreases of 13 to 20 F. No significant mortalities occurred in 12 tests. some temporary l-0ss of equilibrium occurred early in three of five tests with a temperature decrease of 15 to 20 F where specimens were acclimated at 55 to 60 F.

Temperature decreases of 15 to 17 F at acclimation temperatures exceeding 60 F resulted in no loss of equilibrium.

7.4.3.4 Bluegill Rapid temperature increases of 13 to 35 F with specimens acclimated at 32 to 90 F resulted in mortalities in 9 of 37 tests. However, all significant mortalities occurred at test temperatures at or exceeding the lower limit of the avoidance temperatures (Figure 7.4.1-4). Nonsignificant mortalities occurred in 7 of 37 tests (14 of 376 fish). These occurred at temperature increases of 13 to 29 F.

Tests were conducted on specimens acclimated at 45 to 81 F and subjected to rapid temperature decreases of 7 to 20 F.

Mortality was low. Significant mortality occurred in only 2 of 31 tests. Both tests were conducted with a temperature decrease of 15 F. Temporary loss of equilibrium was noted in some specimens when the temperature was decreased 13 to 15 F and 20 F.

No mortality or loss of equilibrium occurred with a temperature decrease of 16 and 17 F.

7.4.3.5 White crappie Some mortality and loss of equilibrium occurred with specimens --acclimated at 32 and 79 F and rapidly subj~cted to temperature increases of 13 to 32 F. Significant mortalities were observed in 3 of 10 tests conducted at temperatures less than the estimated avoidance temperatures but above the preference temperature. Significant mortality was also observed in all of eight tests conducted at or above the upper avoidance

.'~* *' limit (Figure 7.4.1-5) *

~*.

7.4-12

Some loss of equilibrium (35 of 233 fish} was observed ,....._,.

when specimens acclimated at 45 to 71 F were subjected to rapid temperature decreases of 7 to 20 F. No significant mortality was observed in 22 tests. White crappie are sensistive to l~ndlinq stress and consequently results may vary under similar test conditions.

7.4.4 DISCUSSION The studies of the spotfin shiner, channel catfish, bluegill, pumpkinseed and white crappie indicate that mortality (96 hr) was statistically nonsignificant {P~0.05) in temperature shock tests conducted at temperatures below the upper limit of the avoidance temperature during rising field temperatures. Five of sixty rapid temperature increase tests conducted during periods of falling field temperatures resulted in significant mortalities (PS0.05); three were in tests with the white crappie and one each occurred with the spotfin shiner and channel catfish. Mortality in the white crappie and spotf in shiner occurred above preference temperatures. The mortality in one test on the channel catfish occurred below the preference temperature, but when the test was repeated no mortality occurred.

To illustrate that the scheduled operation of PBAPS Units No. 2 and 3 at full power in the open loop made would not cause any significant mortality, the shock data were plotted with the predicted temperatures which may occur in the Pond (Figures 7.4.4-1 to 7.4.4-5). A 5 F water quality criteria line is shown along with a 15 F delta T. These data show that a sudden decrease in temperature of up to 15 F or even higher would cause no mortality. The data are conservative because they are based on instantaneous decreases in temperature. The temperature decrease would not be as rapid during PBAPS shutdown. Thus, based on the laboratory data we can predict that mortalities will not occur at a temperature decrease of 15 F.

Studies indicate that fishes prefer higher temperatures in winter and avoid higher temperatures in summer. Fishes will be distributed relative to their preference and avoidance temperatures. It is because of these differing responses and that fishes will not be trapped in the Pond or in the discharge canal that no mortalities due to shock will occur.

A summary of preference and avoidance temperatures for fishes acclimated to winter temperature (33 F), fall and spring transitional temperatures {40 to 55 F) and high summer temperatures is given in Tables 7.4.4-1 and 7.4.4-2, respectively. Fishes acclimated to high summer temperatures common to the Pond avoid temperatures which are in excess of those predicted for the "worse case" conditions {higher than 7.4-13

93 F). The temperature which the fishes prefer is below the avoidance temperature. In the winter and fall and spring

~ransitional periods the avoidance temperature is also higher than the predicted "worse case" condition. Fishes which come in contact with the plume can be expected to prefer it if their pref erred temperature is higher than the acclimation temperature in the transition period.

The phenomenon of low thermal responsiveness, which is the inability of a fish to avoid areas in the thermal gradient which produce stressful conditions (Meldrim and Gift, 1971) was observed in ~he preference and avoidance studies. Low thermal responsiveness is an ~~~if~g~ which occurs in steep, compressed experimental gradients, 11 c (20 F) or greater, which extends a short distance. It is not relevant in the field situation. The phenomenon rarely occurred in temperature avoidance studies on some 27 species which occur in the Pond. Low thermal responsiveness was most commonly observed in the preference tests where the gradient exceeded 10 C ( 18 F). over a distance of 12 feet. such a gradient averages 1.5 F per foot the acclimation temperature is located in the middle of the gradient. Model studies (Elder, et al., 1973) indicate that such a gradient will not occur in the Pond near PBAPS. In the course of preference experiments the preferred temperature was checked for position effect and the gradient was shifted and occasionally expanded.

When the gradient was 11 c (20 F) or greater {1.67 F per foot) low thermal responsiveness was also occasionally exhibited by some species.

Regardless of its cause, low thermal responsiveness will not be a source of mortality in the thermal plume. At no time will the gradient in the thermal plume approach conditions which would elicit the phenomenon experienced in exp~rimental studies.

Low thermal responsiveness has not been observed in field studies to date. No fish kills have been observed in the Pond or discharge canal.

---*-----~--~* ---------- ---~- --~--

7.4-14

TA 3LE 7 *4 . 4-1 Preference, avoidance and upper temperature (F) tolerance limits of the selected representative fish acclimated to high summer tem-peratures common to Conowingo Pond.

Species Acclimation Preference Avoidance Upper Tolerance Limit Gizzard shad NO DATA AVAILABLE Spotfin shiner 78 95 80 83.5 87.0 81 84.2 87.6 82 84.9 88.l Bluntnose minnow 80 75.2 81 75.7 82 76.2

.channel catfish 80 86.8 94.7 81 87.4 95.Z 96 ...........

82 88.0 95.7 Bluegill 80 87.0 97.Z 81 87.5 97.7 96.5 82 87.9 98.l Smallmouth bass 77 86-90 95 80 88-90 97 82 90 98 Largemouth bass 79 87.3 96 80 87.9 95 82 88.5 98 85 97 White crappie 78 90 80 83.9 91.7 81 84.7 92.1 90 82 85.5 92.6 Walleye NO DATA AVAILABLE Chironomus attenuatus 80 95.5 7 .4-15

' \

\\'a.

TABLR 7.4.4-2 Preference and avoidance temperatures of selected representative fishes acclimated to 33, 40, and 55 F.

Species Acclimation Preference Avoidance Gizzard shad NO DATA AVAILABLE Spot fin shiner 33 50.8 65.3 40 55.7 69.1 55 66.1 77.0 Bluntnose minnow 33 52.3 64.0 40 55.8 68.0 55 63.1 N.A.

Channel catfish 33 58.8 70.8 40 63.0 74.3 55 71.9 81.8 Bluegill 33 66.S 81.5 40 69.5 83.1 i'*.

55 76.1 86.5

,* Smallmouth bass 54 70-73 N.A.

-}*.

• =

L~rgemouth bass 33 59.8 N.A.

,*** . 40 63.9 N.A.

(.

i, ;

55 72.7 - - N.A * -- -- - ------*

White crappie 33 46.4 58.7

.~

40 52.0 65.2

t. 55 64.0 79.3

~ .

t:: Walleye 50-52 59-63 N.A.

~:

t.:

~--

r t~ : N.A. = No data available

~-,;

re ft' 7.4-16

~L.

I l SPOTFIN SHINER

• *' 'FALLING FIELD TEHPERATURES

• No mortality duo to OMortality due to thermal shock th.?rmal shuck 30 20 0

0 10 Temperature 0 0

30 40 so 60 70 BO 90 i

l I

RISING FIELD TEMPERATURES 40

\ e No mortality du~ to O Mortality due to I ......

thermal shock them.al shock Temperature 0

30 40 .50 60 70 80 90 Accl~tion Temperature (f}

TABLE 7.4.1-1 Relationship between rapid temperature increase (shock) and preference and avoidance temperatures (95% confidence intervals of the population mean) during falling 3nd rising field temperatures for the spot(in """"'

shiner, Notropis ~?ilopterus, 7.4-17

CHANNEL CA1'FISll FAIJ.ING t'IELD TEMPERATURES

• No mortality due to O Mortality due to thet'lllal shock thermal shock 40 30 20 10

---

a 0

30 40 50 60' 70 RO 90 Acclimation Temperature (F)

RISING FIELD TEMPERATURES

• tro mortality due to OMortality due to them.al shock the1:1114l shock 30 20 10 Avoidance /

Te.!'l'erature 0

30 40 50 60 70 80 90 Acclimation Temperature (F)

FIGURE 7,4,1-2 Relationship between rapid temperature increase (shock) and preference and avoidance temperatures (957. confidence intervals of the population mean) during falling and risinG field temperatures for the channel catfish, Ictaturus punctatus.

7.4-18

PUMPKINS !::ED .~ ..........

40 FALLING FIELD TEMPER..\TIIRES

• tTo mortality due to themal shock O Mortality due to thermal shock 0

I"' 0 0

.. it a

...."3~r: I*

30

... 0 I.._,

J

I .....

&J u II U 20

~<

it~

• 41 d

... i! Preferred

....IS 0 "t

II GI II I-<

10 "ui:: *

.... &J 0

....... QI 30 40 50 60 70 80 90 A.ccli!IL'l.C ion Tc°'l"*ra cure (F)

RISING FIELD TEMPERATURES 30 e Ho mortallty due to O MoL*tality due to the::inal shock thetmal shock 20 10 0

30 40 so 60 70 BO 90 A.ccl1111ation Temperature (F)

Relationship between rapid temperature increase (shock) and preference temperature (951. confidence interval of the population mean) during falling and rising field temperatures for the purnpkinseed, Lepomis gibbosus.

7.4-19

BLUEGILL FALLING FIELD TEM.PERAnnu:s 50

• No mortality due to O Mortality due to tb.ermal shock thermal shock 40 30

.i 1

20 -

0 10 0

30 40 50 60 70 80 90 Acclilliation Temperature (F)

RISING FIELD TEMPERNl'UR.ES e No mortality due to O Mortality due to thermal shock thermal shock 40 0

JO 40 50 60 70 80 90 Aeell1114tion Temperature (F)

FIGURE 7. 4 , 1-l~

Relationship between rapid temperature increase (shock) and preference and avoidance temperatures (957. ~onfidcnce intervals of the population mean) during falling and rising field temperatures for the bluegill, Lcpomis macrochirus.

1.4-2c

Wltl'l:E CRAPPlB 40 FALLING FIELD TEMPERATURES

• No mort4lity due to O ttortdity due to the'C'ltl.11 shock theroal shock 30 Avoidance Temperature 20 0 eo 0

10 0

30 40 50 60 70 80 90 Accli111.1tion Tcmrcraturc (F)

RISING FIELD TF.MPE!lATUBES 30 e N<.1 mo::-tali.ty d11e to O M.:irtallty due to them;-iL shock. tnermal shock 20 0

10 0 Preferred /

Te111perature

• lQ 30 40 so 60 70 80 90 Acclimation Temperature (F)

FIGURE 7.4.1-5 Relationship between rapid temperature increase (shock) and preference and avoidance temperatures (957. confidence intervals of the population mean) during falling and rising field temperatures for the white crappie,

~ annularis.

7.4-21

90 SPOTFIN SHINER eo 40 0Ri1ing Yield Temperatures

• Fa11i~g Pield Temperatures 30 30 40 50 60 70 80 90 TEST TEMPERATURE (F) EQUIV.\LENT TO TEHl'ERA'IURE OF COl\OWINCO POND UNAFFECTED BY PBAPS.

---

------------ *----- --- * - - ---~------ ----

Plot of rapid temperature decrease tests (shock) in relation to Yater qu4lity criteria (maximum increase in delta T = 5 F) and delta T ~

15 F for the. spotfin shiner, Notropis spilopterus. All points indicate survival unless otherwise indicated.

7.4-22

90 CHANNEL CATP'ISR Water Quality ~

Criteria !:. T

• 5 F AT* 15 40 o Rising Field Temperatures

~ Falling Field Temperatures 30 30 40 50 60 70 80 90 TEST TEMPERATURF. (F) EQUIVALENT IO TE}!PERATURE OF CONOWINCO POND UNAFFECTED BY PBAPS.

FIGURE 7 .4.4-2 Plot of rapid temperature decrease cests (~hock) in rnlJtiJn to water quality criteria (maximum increase in delta T 5 F) and delta T =

A 15 F for the channel catfish, Ictalurus punctatus. All points indicate survival unless other wise indicated.

?.4.-23

90 PUMPKINS EED Water Quality ~

Criteria i6 fl* 5 F 40 o Rising Field Temperatures

• Falling Field Temperatures 30 30 40 so 60 70 80 90 TEST TEMPERATURE (F) EQUIV.\LENT TO TE~PERATURE OF COt'\OWDICO POND UNAFFECTED BY PBAPS.

Plot of rapid temperature decrease tests (shock) in relation to water quality critcri~ (maximum increase in delta T

• 5 F) and delta T

• 15 F for the pwnp!dnsP.ed, ~l'fl~i,!i. tiJi~l':...u.!.* All points indicate

&ui.*viv:il u~].z~~ ::it'.~c:.'1icc indic:i::cd.

7.4-24

90 BLOEGil.L mortality 1 teat ""-

i t 40 olising Field Temp~raturea Ii

• Falling Field Temperatures

!t - - -

i

!I 30 if 30 40 50 60 70 80 TEST TEMPERATURF. (F) EQUIV.\LENT TO TEMPERATURE OF CONOwrnco POND 90 Il UNAFFECTED BY PBAPS.

PIGURE 7,4,4-fi.

Plot of rapid temperature decrease tests (shock) in relation to water quality criteria (maKimum increase in delta T ~ 5 F) and delta T a 15 F for the bluegill, Lcpomis macrochirus. All points indicate survival unless otherwise indicated.

I II 7.4.-25 i

\

I.

\, .*

90 WRITE CRAI'PIE Water Quality ~

Criteria A 'I

• 5 F AT*

i;.

Ij .

i .

t* .

l"*"

i'. .

I,: 40 o Rising Field Temperatures

• FalliQg Field Temperatures 30 30 40 50 60 70 80 90 TEST TEMPERATURE (F) EQUIV,\LEtIT TO TEMPERATURE OF CONOWINCO POND UNAFFECTED BY PBAPS.

[..* f'.JQUR~ 7 .4.4-.5_ _ __

_..l.* - - - - - - - - ~- ---------------

Plot of rapid temperature decrease tests (shock) in relation to water quality criteria (maximum increase in <lclta T = 5 F) and delta T ~

i*

15 F for the white c:rappie, Pomoxis annularis. All points indicate

.. survival unless otherwise indicated

• 7.4-26

.. f.

f .... :,*

8.1 Applicable Effluent Limitation The effluent limitation desired under this alternative is "the discharge to the Pond of an average of 8.5 x 109 Btu/hr.

and a maximum of 16 x 109 Btu/hr."

8.2 System Description.

Two additional "helper" cooling towers would be added to the Peach Bottom circulating water system providing sufficient capacity to accommodate the total circulating water flow and thus cool all of the circulating water before it is discharged to the Pond. The physical layout of the Station with these additional "helper" towers is shown in Figure 8.2-1.

The performance of the helper towers and, therefore, the discharge temperature rise is dependent on meteorological conditions. The monthly variation in discharge temperature rise is indicated on Table 8.2-1. Table 8.2-2 illustrates the resultant variation in evaporative losses from the cooling towers and the water body surf ace. A comparison of the information on

. :* .* these tables with that supplied on Tables 2.2-1 and 2.2-2, for the existing system, indicates that the average rate of heat rejected to the Pond would be about 8.4 x 109 Btu/hr., which is 303 lower than for the existing system, and that the average rate of evaporation would be about 11% greater than for the existing system. This increased rate of evaporative loss would add up to about 792 million gallons of water per year at an 80% load factor.

As in the existing system all of the circulating water flow is returned to the Pond via the submerged jet di~charge.

The transit times for the circulating water will be ess entially the same as those indicated in Table 2.2-3 for that water which goes through the cooling towers. *-

8.3 Schedule and Costs These additional . cooling towers could be installed within a period of 30 months, provided that engineering has been completed and long lead time items such as pumps, pipe, and pilings are available when required.

8-1

The costs involved in implementing this alternative would be:

Capitalized cost of replacement $ 15,790,000 energy ($2,187,000/yr. @ 13.85%)

cost of Lost Capacity @ $200/kw. 3,120,000 Capital cost of Installation

( 1975 Dollars) 22,000,000 Total capitalized cost $ 40,910,000 8.4 Resultant Isotherms The net effect of the addition of these two cooling towers will be lower excess temperatures throughout the Pond.

The degree by which these excess temperatures are lessened will depend upon the seasonal variation of cooling tower performance, as described above. Figures 8.4-1 through 8.4-6C are predicted isotherms for this five helper tower system which correspond to predictions made in reference (2) fc~ the three helper tower system.

~*...

I, .

8.5 Biological Assessment

.i*"

l'. The material presented in section 7 provides the basis for concluding that the operation of PBAPS as presently designed

i. (open loop with 3 "helper 11 cooling towers) will assure the I. protection and propagation of a balanced indigenous community of r!.

r. ~

shellfishes and fishes and wildlife in and on the Pond. The two rr .. additional cooling tower banks will in general cause less of a f *. temperature rise in the Pond. Since it has been demonstrated

[: that no "appreciable" harm to the biota would result due to the L '*

r I, :

operation of PBAPS as designed, it is anticipated that the

,._. additional cooling proposed in this section would have the same

).

impact. It should be emphasized, however, that the predicted enhancement of the Pond biota (due to the thermal input) would be reduced.

- L

\

i I .

), ..

8-2

Table 8.2-1 Peach Bottom Units 2 and 3 Alternative #1 Five "Helper" Cooling Towers Seasonal Variation o! Discharge .1 T

• Alllbient Condenser f\T Cooling Twr. Heat Rejected Discharge /1 T Water Temp. (°F) (°F) Range (°F) via Discharge (109 Btu/hr.) (OF)

January J5.0 20.6 6.6 10.7 14.2 February .36.0 20.8 6.8 10.5 14.0 March J9.5 20.8 6.8 10.5 14.0 April 48.5 20.8 7.3 10.2 13..5 May 64.0 20,8 11.0 7.4 9.8 Ol l

...... June 72,5 20.8 12.,3 6.4 6.5 July 80.0 20.8 15.2 4.2 ,5.6 August 79,5 20.8 14.3 4,9 6.5 September 10.5 20.8 12.3 6.4 8.,5 October 60.0 20.8 10.8 7.5 10.0 November 45.0 20.8 7,6 9.9 1).2 December 35.5 20.8 6.8 10 * .5 14.0 Average Annual During Operation 8.3 11.0

• ' based on average monthly meteorological conditions.

} ) I

Table 8.2-2 Peach Bottom Units 2 and 3 Alternative #1 Five 11Helper 11 Cooling Towers **.

... *~

Seasonal Variation of Rate of Evaporative Loss*

• 'i

.l Evaporative Loss Receiving Water ** Total Evaporative from C. Twrs. (cfa) EvaE* (efs) Losa (o.f's)

January 13.8 16.0 29.8 February ---- 14.2

--- ----- - 14.7 28.9 March 14.2 17.8 32.0 April 15.3 20.4 35.7 May 30.6 17.0 47.3 June 34.3 17.9 52.2 July 42.3 12.2 54.5 August 39.8 14.2 54.0 September 34.3 17.3 51.6 October 30.1 18.8 48.9 November 15.9 19.*8 35.7 December 14.2 17.8 32.1 Average Annual Rate During Operation 24.9 17.0 41.9

• based on average meteorological conditions.

- - - - - - --- ------ -~~--- - -* - - *~~ . . . --.-~

.. ~ ~---~-

calculated us1ng .formulae developed in Brady, Edinger, and Geyer; Heat Exchange and Transport in The Environment; EPRI Publication No. 74-049-00-J.

8-4

EMERGENCY COOLING TOWER

~-\

\

\

\

OUTER SCREEN STRUCTURE SCALE O--~::_-

500 **~000 FEET FIG. 6.2-1 dl.OSEUP OF PEACH BOT ALTERNATIVET~~ COMPLEX 8-5

MUDDY RUil 1 MILE VERTICAL TEMPERATURE PROFILES

'IOLTWDOD 3MILES TEMPERATURE RISE IN ° F ONE FT. DEPTH .!=-!@~ t f ~~ 't f PEACH BOTTOM NUCLEAR PLANT "'"'...

1'2 Jfd 20 DISCK-'AGIE:. TO POND: ~CFS DISDCARG£ TEMP RISE. t..::ti.2 op AVE. OUTGOING TEMP. AT CONOWINGD~F NO, COOi.iNG TOWERS: 5 AVE. INCOMING TEMP. AT HOLTWOOO 3~°F 30 40 FIVE FT. DEPTH eo CX> © I

0-7 8

90 JJHJS@

RESULTS BASED ON ANALYSIS Of ALDEN RESEARCH LABORATORY TEST NUMBER 311 PEACH BOTIOM MODEL STUDY

!.p ::~*!

~i ~

Philadelphia Electric Ca.

~ -* t

~ .. . _ .

• 4_. .. _ . ......... .u - , , . . _. , _ . ~ 0 10,000 PREDICTED CONOWINGO PONO TEMPU?ATURE RISE

~~

~~LQ C1 ~ ~ ~ ~ ~

ABOVE AMBIENT INCOMING WATER TEMPERATURE ISO*

PROTOTYPE SCAlE-FEET THERMS FOR UNITS 2 & ,0 OPERATING \YlTH AVER*

AGE RIVER FLOW OF S . ODD CFS

• -~11 A<<E~tE.

TIONSFOR

-'ANUAJ2'1' ATMOS!'HERIC C:ONOI*

0100 IJOS TUESDAY OPERATIONAL SC:Hl~l>t!LF o ..- ...

§:.:,.-.:, AVERAGE SURFACE HEATTAAflSFEA COEFFICIENT IS 71 BTU Of*1 rr*2oAY' ' *

~.

C57

.I fJGURl N&.

8 .4-1

MUDDY AUN

~ HOLTWOOD VERTICAL TEMPERATURE PROFILES TEMPERATURE RISE IN " F Ol4~8rOOl4~8:o ONE FT. DEPTH 1:~1 ~4 1 I I~ 1:~

... zo @ 20 @

DISCHARGE TEMP. RISE: I'! Of AVE. OUTGOING TEMP. AT CONOWINGD 42.2 °F NO. COOLING TOWERS: '5 AVE. INCOMING TEMP. AT HOLTWOOD 4Q Of FIVE FT. DEPTH co I

-.J 90 RESULTS BASED ON ANALYSIS OF

'ALDEN RESEARCH LABORATORY TEN FT. DEPTH TEST NUMBER :!03 I **1 I ,_ /\ J PEACH BOTTOM MODEL STUDY Phil1dalphi1 Electric Co.

r~~

_, . ._l . . .~~1

. . -.-1--**-* 10,000 PREDICTED CONOWINGO PONO TElf'PEAi\TURE RISE d c*p*-l ABOVE AMBIENT INC0"41t:G WA"ffA TE.MPERATIJAE ISO*

PROTOTYPE SCALE-FEET Tl1ERMS FOR UNITS Z & ?, OPERATING WITH AVER*

AGE RIVER FLOW Or 15,000 CFS AVE.RAGE MAIZCl-I ATMOSl'HERIC CONO\*

TIONS FOR 0100 HRS TUESDAY AVEl\AGE SURFACE: ~EAT TA'-NSFER COEFFICIENT IS 13 ITU oir** Fr1oAv**. ~I FIQUAENP 8 4- 2.

OPERATIONAL SCllEDULE J ) )

VERTICAL TEMPERATURE PROf'ILES ONE FT. DEPTH :r ri.r-TEMPERATURE r

RISE IN 1 '? 01 1 i; ~

IOtz;IJil/A

° F 8

I I()

I

,_20 @ 20 OlSCHAAGE TO POND: :;Y-.::OCFS AVE. OUTGOING TEMP, AT CONOWINGO "4.7°F DISCHARGE TEMP. RISE: ~.8 °F NO. COOLING TOWERS: 5 AVE. INCOMING TEMP. AT HOLTWOOO 04 OF FIVE FT. DEPTH CD I

60 CD 7

8 90 @

RESULTS BASED ON ANALYSIS OF ALDEN RESEARCli LABORATORY TEST NUMBER 218 TEN FT. DEPTH PEACH BOTTOM MODEL STUDY Philadelphia Electric Co.

PREDICTED CONOWINGO POND TEMPERATURE Al SE 0 10,000 A.BOVE A MSIENT INCOMING WATER TEMPERATURE

~ ISOiHERMS FOR UNITS 2& 3 OPERATING WITM PROrOfTPE SC&l.E- FEET AVERAGE R IVER F LOIN OF 10.000 CFS

,!.VEfZAGE MAY ATMOSPHERIC TUE.SDAY iflJI CONDITIONS FOR 0100 HRS.

AVERAG( SURF AC[ MEAT TRANSFER COEFF'ICIE:'T IS 101 BTU Of* I Fr2oAv*1, F1GuR*No.

8 .1-3

VERTICAL TEMPERATURE PROFILES TEMPERATURE RISE IN

• F ONE FT. DEPTH

.:~.~'

,_20 20 DISCHARGE TO POND: ~=-°'.)JCFS ....

DISCHARGE TEMP. RISE: 5.6 VF ..."' 4 ~  :.:i 2 ~ 8 10 ~ 8 NO.COOLING TOWERS:  ::> AVE. OUTGOING TEMP. AT CONOWINGO et) Of ~ 0 0 AVE. INCOMING TEMP, AT HOLTWOOO 00 °F 'i= 10 10

...020 Q.

20 30 30 4 40 FIVE FT. DEPTH

's a::>

I © 60

'° a

90 iQIXPZ@

RESULTS BASED ON ANALYSIS OF ALDEN RESEARCH LABORATORY TEN FT. DEPTH TEST NUMBER B2.

PEACH BOTIDM MODEL STUDY IJ i

'-***~~

Philadelphia Electric Co.

!'**I 2 ...

, t TEMPERATURE A1SE i .. J __,, ..._ ...__. _ , _ ..... ......... . - .

• 0 b

IC,000 PREDICTED CONOV:INCO PON:>

d e1 A80VE AMBIENT INCOMING WATER TEMPER.,.TUll\E ISV*

.-~

TH~ AMS FOR UNITS 2&3

i*, ~

' PROTOTYPE SCAL£ .. fE.ET AGE RIVER Fl.OW Of l&OO CFS QPERATU.G WITH AVER*

uulJi l'

• iT~:J

AVERAGE SURFACE HEAT TRA~SFER COEFFICIENT JS AVEZJ

• ...;c ..;uLy CONDITIONS FOR ulQQ ~*s. TUES~Y ATMOSPHEJHC OPERATIONAL SC"H~llULE o*-1 gj;:."7:::,

12.! BTU0f.1FT*2oAv*1.

tlilJ I FIGURE NO.

8.1- 4 l

i

VERTICAL TEMPERATURE PROFILES

,:g:.: ~ I 'f ,:µ;

CONOWINGO DAM TEMPERATURE RISE IN

• F ONE FT. DEPTH t l r

,_zo @ 20 @

DISCHARGE TO POND : ~ CFS DISCHARGE TEMP. RISE : (o,0 DF 4 I!> 8 10 NO. COOLING TOWERS: 5 AVE. OUTGOING TEMP. AT CONOWINGO 85 Of AVE. INCOMING TEMP. ATHOL TWOOO 85 OF FIVE FT. DEPTH

)J I

© 90 @

RESULTS BASED ON ANALYSIS OF ALDEN RESEARCH LABORATORY TEST NUMBER 2" TEN FT. DEPTH PEACH BDTIDM MODEL STUDY Philadelphia Electric Co.

0 10,000 PREOICTfO CONOWINGO PONO TEMPERATURE RISE 6 eol ADOVE AMBIENT INCOt.tlNG \'IATEA TEMPERATURE ISO*

THEAMS FOR UNIT~ £& 3 1Jr(RA.TJNGWITH AVER-PR010TVPE SCALE *FtET ACiE RIVER F'l.O'll OF ;t!,00 CFS

".*:1 W.:i *Ii=. JUi...Y 0 \lUOSPH£RIC AVERAGE SURFACE HEAT TftANSfER COEFFICIENT IS CONDITIONS .. OH 0700 HHS l< 'E.2~:. 1.:~1*

127 BTU OF. I FT*2 DAY*l .

ifi'J I FIGURE NO.

8 .4-5A SCHEDULE

---

_......,. -- -- ------------------ ----~

MUDDY RUN

--E- HOLTWOOO

'~Al. TEMPERATURE PROFILES TEMPERATURE RISE Ill

• F

@. 4 8

'? 0~1 T ! 'f t

(o I I I

• t.ow + ONE FT. DEPTH

...... 20 @ 20 DISCHARGE TO PONO: j;'.150 CFS DISCHARGE TEMP. RISE: O).u Of 10 NO.COOLING TOWERS: 5 AVE . OUTGOING TEMP. AT CONOWtNGO es Of AVE.tNCOMINGTEMP.ATHOLTWOOO es Of OJ I

I-'

I-'

,,_, +

"1

,_h*i/ FIVE FT. DEPTH

© 60

~o RESULTS BASED ON ANALYSIS OF ALDEN RESEARCH LABORATORY F\..OW + TEN FT. DEPTH TEST NUMBER Z~3 PEACH BOlTOM MODEL STUDY Philadelphia Elecllic Co.

0 PRECHCYEO CONOW"4GO PONO n:MPERAYVRf. RISE b ABOVE. AMBICNT 1NCOMIN(i WATER TEMPERATURE ISO.

THERMS FOR UNITS 2. & 3 OPERATING VvlTH AVER*

PROTOTYPE SCALE-FEET AGE RIVER FLO'NOF 2~00 CFS

£.<T~SME JiJi.Y ATMOSPHER1C ljJ I AVERAGE SURFACE !iEAT TRANSFER COEFFICIENT tS COfllt>ITIONS FOR :BOO HRS- Tl-IU~DAY 121 aru*f.1 fT-2 DAY"'* FIGURE NO.

S.4-5B j ) )

.. -* ,_ .. * ' .,,. ... ~.-* ,**~*

MUDDY RUN TMILE HOLTWOOO 3MILES

• VERTICAL TEMPERATURE PROFILES TEMPERATURE RISE IN

• F

'~

00 z. 4 " 6 <O ONE FT. D~PTH 10

~

,_ 20 @ 20 @

DISCHARGE TO POND: ~CFS DISCHARGE TEMP. RISE; 6.0 Of

.. 1Q

" 10 NO.COOLING TOWERS: 5 AVE. OUTGOING TEMP. AT CONOWINGO 85 Of AllE. INCOMING TEMP. ATHOLTWOOO 6? Of 40 FIVE FT. DEPTH D so 60 go IMA'r4 @

RESULTS BASED ON ANALYSIS OF AL.OEN RESEARCH LABORATORY now + TEN FT. DEPTH TEST NUMBER 2a~

PEACH BOTTOM MODEL STUDY Philadelphia Electric Co.

0 PREOICTEO CONOW1NGO PONO TEMPERATURE RISE L ABOVE AMBIENT INCO~~ING WATER T£MPEAA1URE ISO THERMS FOR UNtTS 2 3 6, OPERATING WITH AVER*

PROTOTYPE SCALE-FEET AGE RIVER FlOW OF 2500 CfS r.xr~Mi::.JULY ATMOSPHERIC CONDITIONS FOR 1700 HRS. SUNDAY AVERAGI:: SURFACE HEAT TRANSFER COEFflCIENT IS 121 oru*F-'Fr*oAv**. liJ I FIGURE NO.

8.4-5C

~ MUDDYRUN HOLTWOOD VERTICAL TEMPERATURE PROFILES CONOWINGO DAM TEMPERATURE RISE IN

• F 12 '"20 o a o

~ 10~ o['3T"'

4 12 1420 ONE FT. DEPTH 10 f-20 @ 20 DISCHARGE TO POND: 330 CFS

... IZ 14 2.:J

~ 01'1--T--i'-'1i'--T'-,

DISCHARGE TEMP. RISE: li!>.2. Of NO.COOLING TOWERS: ';'; AVE. OUTGOING TEMP. AT CONOWINGO AVE. INCOMING TEMP. ATHOL TWOOO 45 45 Of

°F

~

ozo 10 40 4 I!.,~,.,~,~~,,----

FIVE FT. DEPTH G:l

© I

w RESUL:rS BASED ON ANALYSIS OF ALDEN RESEARCH LABORATORY TEST NUMBER 205 FLOW TEN FT. DEPTH PEACH BOTTOM MODEL STUDY Philadelphia Electric Co.

0 PREDICTED CONOWINGO POND TEMPERATURE Als.E 6 ABOVE AMBIENT INCOMINC WATER TEMPERATURE ISO*

THEHMS FOR UNITS 2 & J OPERATING "41T.,_. AVER*

P~OTOTYPE SCALE-FEE.T AGE RIVER FLOW OF 2500 CFS AVEE!_A~E N)V£H5Eg ATMOSPHERIC AVERAGE SURFACE t-IEAT TRANSl=EA COEFFICIENT IS

?C:> Btu***' .... DAv*I.

.$'I OONOITIONS FOR FIGURI NO.

0700 HRS. TUESDAY 8 4-6A

)

~ .. . - ": *~. ' __ ,*.:...: . ~- - ..

. . ~

CONOWINGO OAM VERTICAL TEMPERATURE PROFILES TEMPERATURE RISE IN

• F ONE FT. DEPTH 1f>2f.:~

20~

OISCHARGE TO PONO: ~CFS DISCHARGE TEMP. RISE: 1?.Z. Of NO.COOLING TOWERS: 5 AVE. OUTGOING TEMP, AT CONOWINGO 45 AVE. INCOMING TEMP. AT HOLlWOOO 4$

FIVE FT. DEPTH 50

0

....I © 60 7

8 90 =@-*--

RESULTS BASED ON ANALYSIS OF ALDEN RESEARCH LABORATORY TEN FT. DEPTH TEST NUMBER 205 PEACH BOTIDM MODEL STUDY Philadelphia Electric Co.

PREDICTED CONOWINCiO POND TCMPFRATUAE FllSE

.0.80VE AMBIENT INCOW.l~G WATER TE.MPCRAru ;*E ISO THERMS FOR UNIT!I 2 &3 OPERATING WITH AVEA*

PROTOTYPE SCALE-FEET A.GE RIVER FLOW OF 2i'.JOO CFS AVEKt.*;.<=. t~:::>v<>lt *l:;:: ATPl.OSPHEAIC CONDITIONS FOR *8C.O H., wEr;;1JE )A"f rllJ I -

AVERAGE SURFACE HEAT TRANSFER C:CEFFICIENT 15 1fD BTU Of.1 FT*2 DAY"1, FIGURE ..o 8 .4 -68

---

~-

..-e- MUDDY RUN HOLTWOOO VERTICAL TEMPERATURE PROFILES ONE FT. O!PTH ,i2:"' TEMPERATURE RISE IN

~ 'f p@121f' 20

" F 1

......~ ~ B DISCHARGE TO PONO: Z,SOcFS ...

DISCHARGE TEMP. RISE:J;..2. Of NO.COOi.iNG TOWERS: 5 AVE. OUTGOING TEMP. AT CONOWINGO 45 Of AVE. INCOMING TEMP. ATHOL TWOOO 46 Of FIVE FT. DEPTH co 60

\I\ 7 e

90 @

RESULTS BASED ON ANALYSIS OF ALDEN RESEARCH LABORATORY TEST NUMBER 205 TEN FT. DEPTH PEACH BOTIOM MOOEL STUDY Philadelphia Electric Co.

0 10,000 PAEOlC'TEO CONOWINGO POPllO TEMPERATURE R1S~ I b ,...j ABOVE AMBIENT INCQr.!lr.iG WAfEA ifM?EAA.lURE 15'..)

THERMS FOR UNIT?> 2 &3 *QPf;RA?INCi WITH AVER:*

PROTOTYPE SCALE-FEET AGE RIV~R Fl.OWOF 2500 CFS AVE~.A~E. ~*.::>./C:!*lC:~i..: ATMOSPHE.~IC AVERAGE SURFACE HEAT TRANSFER COEFf'ICtENT 15 CONDITIONS FOR *~*')0 HRS. -::..J;' CA'{

/(Q BTU Of.I fT*l DAY'I. .Q a I FIGURE NO.

lllS'I s.4-6c

)

9.0 9.1 Applicable Effluent Limitation The effluent limitation initially desired is the same as that for Alternative #1: "the discharge to the Pond of an average of 8.5 x 109 Btu/hr. and a maximum of 16 x 199 Btu/hr".

Should the results of the biological studies proposed harein indicate that this mode of operation is harmful to the aquatic community, effluent limitations would then be established to further limit the effect of the thermal component of the discharge on the biota of the Pond.

9.2 System Description The cooling system proposed to meet this initial alternative effluent limitation is identical to that described under Alternative t1. However, should a more stringent effluent limitation be imposed, after the evaluation of the biological studies proposed herein, the system will be further modified to incorporate a return channel and other required changes to permit operation over a range of recirculation and blowdown rates. *The rate of blowdown would be regulated to meet this more stringent, and biologically determined, effluent limitation.

The initial physical layout of the Station would be as indicated in Figure 8.2-1 for Alternative #1. If the return~

channel is constructed the physical layout would be as indicated  ;

in Figure 10.2-2 for Alternative #3.

9.3 Schedule and Costs The schedule and costs for the initial development would be the same for Alternative #1. Following the completion of this construction a biological monitoring program would be undertaken for a period of one year in order to verify the sufficiency of this mode of operation. Should more stringent limitations be found necessary, the construction of the return channel and other required modifications could be accomplished within a period of 23 months, provided that engineering has been completed and long lead time items such as pipe and pilings are available when required.

9-1

The costs involved in the implementation of this work.

in addition to the costs shown under Alternative #1, would be:

Capacity Penalty Due to Increased Turbine Backpressure *****************

• Capitalized Cost of Lost Energy Due to Increased Turbine Backpressure.....

• capital Cost (1975 Dollars) ********** $ 12,000,000

• The additional costs for the operation of this system cannot be estimated until the effluent limitation that will govern its operation has been determined.

9.4 Resultant Isotherms The isotherms that would result from operatioil of these Units with the initial development would be the same as those predicted for Alternative #1. Those resulting from operating to meet a more stringent effluent limitation. if imposed. canno~ be predicted until the limitation has been established.

9.5 Biological Impact The material presented in Section 7 provides the basis for concluding that the operation of PBAPS as presently designed (open loop with 3 "helper" cooling towers) will assure the protection and propagation of a balanced indigenous community of shellfishes and fishes and wildlife in and on the Pond. The two

.. additional cooling tower banks will in general cause less of a temperature rise in the Pond. Since it has been demons~rated that no "appreciable" harm to the biota would result due to the operation of PBAPS as designed, it is anticipated that the additional cooling proposed in this section would have the same

• '

• impact. It should be emphasized, however, that the predicted enhancement of the Pond biota (due to the thermal input) would be reduced.

• 1 ;

9-2

10.0 ALTERNATIVE #3 - FIVE COOLING TOWERS WITH VARIABLE

~~Q~22~:-----------------------------------------

10.1 Applicable Effluent Limitation The effluent limitation desired under this alternative is "the discharge to the Pond of an average of 5.ti x 10 9 Btu/hr.

and a maximum of 16 x 109 Btu/hr. 11 10.2 System Description The additional cooling towers and a return channel would be added to the Peach Bottom circulating water system to enable the system to be operated over a range of recirculation and blowdown rates from open cycle to closed cycle. The system would have the capability of regulating blowdown rates to maintain the 5 F excess temperature isotherm within a defined mixing zone.

The mixing zone desired for this mode of operation would be one-half of the river width and downriver to the Pennsylvania-Maryland State Line. This area is shown on Figure 10.2-1. The physical layout of the Station with the additional cooling towers, the return channel, and other necessary modifications is shown in Figure 10.2-2.

It is estimated that the permissible blowdown rate, which is a function of river flow, temperature and meteorological conditions, will vary between 50,000 gpm and 1,500,000 gpm with *"""""'

an annual average of about 767,500 gpm. A tabulation of the estimated monthly quantity and temperature of blowdown for average river flows and meteorological conditions is presented in Table 10.2-1. Table 10.2-2 indicates the resultant seasonal variation in evaporative losses from the cooling towers and the water body surface.

A comparison of the information on these tables with that supplied on Tables 2.2-1 and 2.2-2, for the existing system, indicates that the average rate of heat rejected to the Pond would be about 5.4 x 109 BtU/hr., which is 55% lower than for the existing system, and that the average rate of evaporation would be about 21% greater than for the existing system. This increased evaporative loss would add up to about 1,490 million gallons of water per year at an 80% load factor.

~~- ---10.3-- -

Schedule

- - - - - --and

- - --Costs The installation of the additional cooling towers, the return channel, and all other necessary modifications could be completed within a period of 30 months, provided that engineering has been completed and long lead time items such as pumps, pipe, and pilings are available when required.

10-1

f r:

..t*

t*

). The costs involved in implementing this alternative would be:

\:.

~*

l

! capitalized cost of Replacement rr Energy ($2,564,000/yr. ID 13.85%)

ir .................... $ 18,513,000 cost of Lost capacity~ $200/Kw ********* 5,920,000 L

~

L.I capital cost of Installation (1975 Dollars) ********************* 34,000,000

'(.*

t,.

Total capitalized cost ****************** $ 58,433,000 10.4 Resultant Isotherms The blowdown from the circulating water system will be regulated to limit its effects to the area of the mixing zone i'

described above.

I i~

10.5 Biological Impact rt r The material presented in section 7 provides the * ~asis for concluding that the operation of PBAPS as presently designed (open loop with 3 "helper" cooling towers) will assure the protection and propagation of a balanced indigenous community of shellfishes and fishes and wildlife in and on the Pond. The two additional cooling tower banks and return canal will allow the heated discharge to be sufficiently limited to meet very stringent effluent criteria. Since it has been demonstrated that no "appreciable" harm to the biota would result due to the operation of PBAPS as designed, it is anticipated that the additional cooling and reduction in affluent quantity proposed in this section would have the same impact. It should be emphasized, however, that the predicted enhancement of the Pond biota (due to the thermal input) would be reduced.

10-2

__......._ _ _ _ _ ... _ .~-. ~ **....v *.: * ..:... ............ ... * . * ~- ~ .. ,*--** ** *-~, *. **-~** ....., ......... -*. ~.,., *****-* - * * * *

• TABLE 10.2-1 PEACH BOTTOM UNITS 2 AND 3 ALTERNATIVE #3 FIVE COOLING TOWERS, VARIABLE BLOWDOWN SEASONAL VARIATION OF BLOWDOWN*

Ambient Condenser A T Cooling Twr. Blowdown Water Temp. ( °F) {OF) Range ~OF) ( 109 Btu/Hr. ~ (cfs) AT (°F)

January 35.0 20.8 12.4 6.4 1092 26.0 February 36.0 20.8 12.3 6.5 1203 24.o March 39,5 20.8 10.9 7,5 1493 22.5

...... April 48.5 20.8 10.3 8.0 2451 14.5 0

....,I May 64.o 20.8 13,9 5.3 1805 13.0 June 72.5 20.8 14.5 4.7 2005 10.5 July 8o.o 20.8 14.8 4.6 3387 6.0 August 79.5 20.8 14.6 4.7 3208 6.5 September 70.5 20.8 15.6 3.9 1404 12.5 October 60.0 20.8 16.3 3.4 891 17.0 November 45.0 20.8 15.6 4.o 691 26.0 December 35 .5 20.8 13.6 5.5 891 27.5 Annual Average During Operation 5.4 1710 17.2

- *- based on average monthly riverflowsandmeteoroJ ~~ic al conditonS:- - - - - - - - - - - - - -

\ \

TABLE 10.2-2 PEACH BarTOM UNI'!'I;; 2 AND 3 ALTERNATIVE #3 FIVE COOLING TOWERS, VARIABLE BLOWDOWN Seasonal Variation of Rate of Evaporative Loss*

Evaporative Loss Receiving Water** Total Evaporative from C. Twrs. ~cfs~ EvaE* ~cf's} Loss (cfs)

January 25.9 9.6 35.5 February 25.7 9.1 34.8 March 22.8 12. 7 35 .5 April 21.5 16.0 37.5 May 38.7 12.2 50.9 June 40.4 13.2 53.6 July 41.2 13. 3 54.5 August 40.7 13.6 54.3 September 43.5 10.5 54.o October 45.4 8.5 53.9 November 33.4. 8.o 41.4 December 28.3 11.9 40.2 Average Annual Rate During 34.o 11 *5 1 ~5 .5 Operationg

• based on average meteorlogical conditions and river flows.

• • calculated using formulae developed in Brady, Edinger, and Geyer; Heat Exchange and Transport in the Environment; EPRI Publication No. 74-049-00-3.

10-4

I-'

PEACH BOTTOM 0

I ATOMIC POWER

\..'l.

STATION Figure IO. 2-1 I I I I I 0 3000 6000 PEACH BOTTOM UNITS 2 AND 3 Proposed Mixing Zone for

- - -Alternative *-# -3 i

) I

EMERGENCY COOLING TOWER

\ \

'\---~

OUTER SCREEN STRUCTUqE *..

COOt,.t .. G TOW£R PUMP STRUCTURE PONO MEW C.W. RETURN CHANNEL SCALE o..___!l_o._0_ _11.....

'oo 'E£T FIGURE 10.2-2 CLOSEUP OF PEACH BOTTOM COMPLEX ALTERNATIVE11=3 10-6

11.0 LITERATURE CITED Alabaster, J. s. 1969. Effects of heated discharges on freshwater fishes in Britain, p. 354-381. In P. A. Krenkel and F. L. Parker (eds.) , Biological Aspects of Thermal Pollution. Vanderbilt Univ. Press, Nashville, Tennessee.

Bennett, o. H., and J. w. Gibbons. 1975. Reproductive cycles of large-mouth bass, (MiQIQQt§!~2 .§~1IDQig~§) in a cooling reservoir. Trans. Amer. Fish. Soc., 104: 77-82.

Breder, c. M., Jr., and D. E. Rosen. 1966. Modes of reproduction in fishes. Amer. Mus. Nat. Hist., Nat. Hist.

Press, Garden City, N.Y. 941 p.

Calhoun, A. 1966. Inland fisheries management. Dept. Resources Agency- Game and Fish, Calif. Resources Agency. 546 p.

carlander, K. D. 1945. Age, growth, sexual maturity, and population fluctuations of the yellow pike perch,

§ti~Q2t~giQn Y!tEgum vit~gym (Mitchill), with reference to the commercial fisheries of Lake of the woods, Trans. Amer.

Fish. soc., 73: 90-107.

---

state

• Univ.

1969. Handbook of freshwater fishery Press, Ames, Iowa. 725 p.

biology. Iowa coble, o. w. 1967. Relationship of temperature to total annual growth in adult smallmouth bass. J. Fish. Res. Bd. Canada 24: 87-99.

Coutant, c. c. 1962. The effect of a heated water effluent upon the macroinvertebrates riff le fauna of the Delaware River.

Proc. Amer. Acad. Sci. 36: 58-71.

Cowell, B. c. 1967. The copepoda and Cladocera of a Missouri River Reservoir. A comparison of sampling in the reservoir and discharge. Limnol. Oceanogr. 12: 126-136.

Edmondson, w. T. (ed.). 1966. Freshwater biology. John Wiley &

Sons, Inc. New York.

Elder, R. A., F. H. Werd, A. R. Bird and M. F. Al-Kegily. 1973.

Predicted prototype temperature distribution in conowingo

~~ Pond. summary report, Peach Bottom Units No. Z-and 3, - Model Study. Bechtel Power Corp., San Francisco, 127 p.

Elser, H. H. 1963. Patuxent River creel census. Nat. Res.

Inst., Univ. of Md. Ref. No. 63-53.

11-1

---

* 1965. Effect of a warmed water discharge on angling in the Potomac River, Maryland, 1961-1962. Progr. Fish.

Cult. 27: 79-86.

Environmental Devices Corporation. January 1974. current Velocity Meaurements, Conowingo Pond.

Eschmeyer, P. 1950. The life history of the walleye in Michigan. Bull. Inst. Fish. Res. No. 3, Univ. Michigan, 99 p.

Euston, E. T., P. G. Heisey, D. Mathur, G. A. Nardacci, T. w.

Robbins and T. F. Rosage. 1974. Biology of fishes, p. 4-25 to 4-79, In T. w. Robbins and n. Mathur, Peach Bottom Atomic Power-station preoperational report on the Ecology of Conowingo Pond for Units No. 2 and 3. Ichthyological Associates, Inc., Drumore, Pennsylvania, xviii+ 349 p.

Forbes, s. A., and R. E. Richardson. 1920. Fishes of Illinois.

Ill. Nat. Hist. surv., Urbana, Illinois. cxxxi + 357 p.

Hansen, D. F. 1943. On the nesting of the white crappie, gQIDQ~l§ ann.Y.!s!i§, Copeia 19Ll2 (4): 259-260.

Hansen, D. F. 1951. Biology of the white crappie in Illinois.

Bull. Ill. Nat. Hist. Surv. 25 (Art. 4): 209-265.

Heincke, F. 1913. Investigations on the plaice. General report I. The plaice fishery and protective measures. Preliminary brief summary of the most important points of the report.

Cons. Intern. Explor. Mer., Rapp. et Proc.-Verb., 16: 67 p.

~

Huber, w. B~na,* L. E. Binkley. 1935. Reproduction and growth of the white crappie, fQIDQ~i§ fillil~lari§ in Meander Lake. Ohio Bur. sci., Res. Bull. 91 p.

Jackson, c. H. N. 1939. The analysis of an animal population.

A. Anim. Ecol. 8: 238-246.

Kramer, R. H., and L. L. Smith, Jr. 1962. Formation of year classes large-mouth bass. Trans. Amer. Fish. Soc. 91: 29-4,.

LaFaunce, D. A. 1960. comparison of some aspects of white crappie, gg~Q~b2 annularis and black crappie, Pomoxis niqr2m~£~l~~g§, life--histories. calif. Inland Fisheries Rept. No. 60-9. 13 p.

\: '

Langford, T. E. 1972. A comparitive *assessment of thermal aspects in some British and North American rivers, p. 319-11-2

351. In R. T. Oglesby, c. A. Carlson and J. A. Mccann......

(eds.). River Ecology and Man. Academic Press, New York.

Latta, w. c. 1963. The life history of the smallmouth bass, Mi£~Q2t§fg§ gQ!Omi§ui gQ!Qmi~Yi at Wangoshance Point, Lake Michigan, Mich. Dept. Cons., Inst. Fish. Res. Bull. 5. 66 p.

Lee, F. G., G. D. Veith. 1971. Effects of thermal discharges on the chemical parameters of water quaiity and eutrophication (submitted for publication in the Proc. Intern. Symp. for Identification and measurements of pollution, Ottawa Canada, June 1971).

Marcy, B. c., Jr. 1971. CYAP canal winter creel census. In Resident fish population dynamics and early life history

- - - - studies. Connecticut - River - Ecological Study ,_.....15th semi-annual Rept. 59 p.

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~--~--* 1975b. Analysis of Total Zooplankton Denisites in conowingo Pond, comparison of Preoperational Period vs.

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~~-----* 1975c. Relationship Between Total Zooplankton Densities in onowingo Pond and Water Flows and Temperature at Holtwood Dam (Jan-Dec). Philadelphia Electric Company.

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• 1975e. ~nalysis of Plant Pigment

• Chlorophyll ~

~--(Total) in Conowingo Pond, Comparison of Preoperational Period vs. Postoperational Period. Philadelphia Electric Company.

---~----* 1975f. Relationship Between Plant Pigment.

Chlorophyll g (Total) in Conowingo Pond and Water low and Temperature at Holtwood Dam. Philadelphia Electirc company.

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. 1975h. Analysis of Benthos Densities and Biomass in

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conowingo Pond, comparison of Preoperational Period vs.

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Postoperational Period (June-Oct)

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---

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~------- 1975b.

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,........\.

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* 1975d. Arialysis of Ambient Water Temperature in conowingo Pond, Station 13 vs. Station 18. Philadelphia Electric company.

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