LAKE MICHIGAN
      ENTRA.IRMENT STUDIES
  BIG ROCK NUCLEAR POWER PLANT
      ESCAHABA POWER PLANT
     NOVEMBER-DECEMBER 1971
     Grosse lie Laboratory
Environmental Protection Agency
Office of Research & Monitoring
         9311 Groh Hoad
   Grosse lie, Michigan U8133
    R-4;,:V;i Vj, Libraiy
    '-?30 .- ,- -  ,\ Do-rrbc'ra Straot
          January 1972
     Grosse lie Laboratory
     Working Report No. 1

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                               Lake Michigan
                            Entrainment  Studies
                        Big Rod; Nuclear Power Plant
                            Escanaba Power Plant
                          November-December,  1971


Purpose:  To determine if whitefish or lake trout  eggs are drawn in with
     the cooling water of power plants and if phytoplankton productivity and
     zooplankton viability are affected  by the cooling systems.

Background:  In the outlining of possible detrimental effects of power plants
     the possibility of the passage of fish eggs through condensers has been
     indicated.  The fluctuating fish population makes it necessary to examine
     all conditions that might have detrimental effects  on valuable fish
     stocks.  Tftiitefish and lake trout are known to spawn on the rocky shores
     of Lake Michigan.  Many of the power plants intakes extend into Lake
     Michigan a sufficient distance to be near these rocky areas.  The
     possibility exists that fish eggs could be drawn in with the  cooling
     water.

Scope:  Two power plants were selected on the basis of their proximity to
     whitefish spawning areas.  The intake of Big  Rock Nuclear Plant near
     Charlevoix, Michigan extends 2000 feet offshore into 30 feet  of water.
     The plant draws 50*000 gallons of cooling water per minute through a
     36-inch pipe to a forebay containing trash rocks.   At the time of this
     study, many ripe male lake trout were taken from the forebay  indicating
     presence of spawning fish around the intake.  Large populations of
     whitefish are known to inhabit Traverse Bay to the  south and  the Beaver
     Islands to the north-

          The second test site was the Escanaba Power Plant at Escanaba,  
     Michigan.  This plant has a shore intake in Little  Bay De Noc.  Little
     Bay De Hoc supports a large population of whitefish; however, the exact
     location of spawning sites is not known. The Escanaba Power  Plant pumps
     approximately 8,000 gallons of cooling water  per minute.

         During the fish egg entrainment study, it was possible to conduct
     phytoplankton-zooplankton entrainment studies.  These studies were conducted
     on samples collected from the forebay and effluent  channel of the Big Rock
     Nuclear Plant and samples from the  open water in front of the intake of
     the Escanaba Power Plant and from the discharge pipe.

Methods:  To separate fish eggs from the intake water a  specially  constructed
     fish egg pump on loan from the State of Ohio  was utilized.  This device
     has a large 20 mesh-to-the-inch screen inside a drum on the suction side
     of a 3-inch purap.  The egg pump strains 20,000 gallons per hour.

         The effects of entrainment of the phytoplankton were measured by
     estimating primary pi eduction with  a radioactive tracer, Carbon lU.  The
     effects of entrainment of zooplankton were measured by determining the
     ratio of live to dead zooplankton at the time of collection and after
     holding the plankters in a water bath for 2k  hours  at inlet water temper-
     atures.  The samples were collected by passing 10 gallons of  water through

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     a Ho. 10 mesh net.  The net was nearly submerged to avoid damaging the
     organisms.  After counting, the samples were preserved for future
     identification and enumeration.

Results and Discussion:  Big Rock lluclear Plant
                         Fish i"g Untrainment
Date
11/9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
Hours
Pumped
0900-2400
0100-2400
0001-2400
0001-2400
0001-1200
1600-2400
0001 -0300
1800-2400
0001-0800
1800-2400
0001-0800
1800-2400
0001-0800
1800-2400
0001-0800
0800 -2400
0001-0800 x
1800-2400
0001-0800
1800-2400
0001-1800
16 00 -2 400
1700-2400
Total
Hours
13
24
24
24
12
8
14
14
14
14
14
8
6
14
18
8
7
Water
Temp F
52
52
52
52
52
52
52
52
53
52
50
47
47
46
47
47
47
Number of Eggs
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
                                                                1 Sucker
                                                                2 Chubs
                                                                1 Sucker
                                                                1 Crayfish

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Date
26
27
28
Total
Hours
Pumped
1730-2400
1730-2400
1700-2400

Total
Kov rr-
6.5
6.5
7
256
Water
Temp ? ITunber of Eggs
47 0
46 o
46

                                                                 ffi.sc
256 hr. x 20,000 gph = 5,120,000 gallons pumped
                          Escanaba Power Plant
Date
11/30*
12/1 *
12/2 **
12/3 **
12/4 **

Hours
Pumped
1600-2400
0015-0800
1600-2400
0015-0800
1600-2400
0001-0330
1600-2400
0015-0300
1600 -24oo

Total
Hours
8
16
16
16
16

Water
Temp F
36
36
35
35
35

Number of Eggs Misc
clump of small 37 smelt
brown eggs 1 chub
2 smelt
1 crayfish
no eggs
no eggs
cluster of
small eggs
Total                 72

 *Tnlet outside of screens
**Inlet inside of 1^/2 inch screens

72 hr. x 20,000 gph = 1,440,000 gallons puirped
     As indicated by the pumping of over 6 million gallons of intake water
at the tvo power plants, the passage of vhitefish and lake trout eggs
through these plants is insignificant.  Two explanations can be put forth on
the lack of fish eggs in the intake water.  The first is that the eggs were
not present around the intake areas.  Very few female lake trout were cap-
tured by the biologists from the State of Michigan indicating that perhaps
the spanning population was small.  The second possibility is that the eggs
vere deposited on the rocky bottom and were not resuspended although egg

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Date
26
27
23
Total
Hours
Pumped
1730-2400
1730-2400
1700-2400

Total
Eours
6.5
6.5
T
256
Water
Temp ?
^7
46
46

ITuriber o^ Eggs
0
0


                                                                  Misc
256 hr. x 20,000 gph = 5,120,000 gallons pumped
                          Escanaba Power Plant
Date
11/30*
12/1 *
12/2 **
12/3 **
12/4 **
Hours
Pumped
1600-2400
0015-0800
1600-2400
0015-0800
i6oo-24oo
0001-0330
l6oo-24oo
0015-0300
1600 -24oo
Total
Hours
8
16
16
16
16
Water
Temp F
36
36
35
35
35
Number of Eggs
clump of small
brown eggs

no eggs
no eggs
cluster of
small eggs
Misc
37 smelt
1 chub
2 smelt
1 crayfish



Total
72
 *Inlet outside of screens
**Inlet inside of 1/2 inch screens

72 hr. x 20,000 gph = 1,440,000 gallons pusrped
     As indicated by the pumping of over 6 million gallons of intake water
at the two power plants, the passage of whitefish and lake trout eggs
through these plants is insignificant.  T-.-ro explanations can be put forth on
the lack of fish eggs in the intake water.  The first is that the eggs were
not present around the intake areas.  Very few female lake trout were, cap-
tured by the biologists from the State of Michigan indicating that perhaps
the spa-inning population was small.  The second possibility is that the eggs
ware deposited on the rocky bottom and vere not resuspended although egg

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pumping operations were conducted through a severe storm during which large
quantities of fine sand were trapped in the egg pump  indicating wave currents
were reaching the bottom.
                        Phytoplankton and Zooplankton

     Primary production of the intake water -was less than the accuracy
of Carbon lA test.  The amount of sunlight available during the test period
was extremely low.  Additional tests will have to be made when more phyto-
plankton are present.

     Representative zooplankton samples were very difficult to obtain  evan
with exact timing of intake and discharge samples.  The sampling difficulty
resulted from the uneven distribution of zooplankton.

     The ratio of the number of live zooplankton to the number of dead
plankters provides the best indication of the condition of the zooplankton
population.  Most populations have some dead organisms resulting from  natural
reproduction, growth and death.  However, additional stress to the population
will result in a lower than natural live/dead ratio.

     The zooplankton population during the survey was comprised mainly of
copepods (Cyclops and Diaptomus) and averaged 17-^ and 10-9 plankters  per
liter in the inlet and discharge, respectively.  These samples were held
in a water bath for 2h hours at inlet temperatures prior to preservation.

     The low live/dead zooplankton ratio of the Big;Sock Plant inlet
indicates that zooplankton were damaged while being drawn, through the
inlet pipe or the population was adversely affected by severe storms
which occurred during the sampling period.  The lower ratio of the number
of live zooplankton verses the number of dead plankters in the discharge
water indicates that the passage of the zooplankton through the pumps  and
condenser tubes resulted in further mortality to zooplankton.  It is not
possible to separate the degree of detrimental effects other than the  effect
of passage of zooplankton through the intake pipe.  The mechanical and thermal
damage through the plant is not separable.  The difference in the live/dead
ratios between the inlet and outlet is equivalent to a 55 percent mortality
at the population sizes observed.  The mortality would be 29 percent if the
discharge live/dead ratio is applied to the intake population.  Regardless
of whether the mortality is 29 or 55 percent, there appears to be significant
zooplankton mortality.  The mortality is higher than has been reported in the
literature for laboratory experiments.  There are many possible reasons for
the high mortality, however, it night be more realistic to wait until  data is
available from other seasons, especially when the cladoceran Bosnina is the
predominate zooplankter.

     The li"e/dead zooplankton ratios obtained at the Escanaba Power Plant
were nuch higher than were observed at Big Rock.  The higher survival  could
have resulted from shoreline intake.  There was a mortality of zooplankton

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as they passed through the Escanaba Plant as indicated  by the  lover ratio of
ihe effluent sample.  The difference in the ratios of the inlet  and effluent
sas^les is equivalent to a 7 percent mortality at  the inlet population  size.
The variation in the intake and discharge population  is greater  than the
variation in the live/dead ratio.

     In summary, the passage of vhite fish and lake trout eggs through  the
Big Rock ITuclear Plant and the Escanaba Power Plant does not appear to  be
significant.  There is mortality of zooplankton as they pass through the
power plants.  There is the additional possibility of mortality  resulting
from the organisms passing through the 2000 ft. intake  pipe at the Big  Sock
Plant.

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Rsglon V9
230 Sou-uh  Dcarbo'm Street
     i^o., IX.Uno.is  60GO*

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