ML19224D579

Proposed Amend to ETS

ML19224D579
Person / Time
Site:	Millstone
Issue date:	07/02/1979
From:	NORTHEAST UTILITIES
To:
Shared Package
ML19224D575	List: L-77-015, Analysis of Exposure Panel Data Collected at Millstone Point, Prepared by Mit ML19224D574 ML19224D579
References
ETS-790702, TAC-10857, TAC-11936, NUDOCS 7907120647
Download: ML19224D579 (68)

Text

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ENCLOSURE A 1.0 Proposed Changes Certain changes prc;.;ose to delete programs which are complete.

Others reflect improved techniques and redistribucion of effort designed to improve the sensitivity of the programs.

7he changes are detailed below and in Attachment 1.

A.

B_enthic Survey, Section 3.1.2.1.5 Stations 1, 4, 5, 7, 10, 11 and 12 are deleted from Figure 3.1-1.

Remaining stations are renumbered and one is added at the intake (#6).

The specification is generally simplified.

The amount of bottom to be sampled is referenced in area covered, 0.1 m rather than in nr.;ers of replicates of a given core size.

The sieve mesh size is reduced from Imm to.5mm.

All rock sampling is deleted. The sampling device is left unspecified.

B.

Trawling, Section 3.1.2.1.7 Figure 3.1.2 is incorporated into the trawl survey and all extraneous stations are deleted.

Only stations 2, 5, 6, 8, 11 and 14 remain.

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e Also the phase "and to give data on reproductive activity, and condition factors" is removed from the objective.

C.

Entrainment Studies, Section 3.1.2.1.9 It is proposed that the fall (Octobtr, November, December) entrainment sampling effort be reduced from 18 samples per week to six (3 days and 3 nights) samples. The proposed changes are indicateo as changes 4 and 5 in Attachment 1.

Changes 1, 2 and 3 also shown were previously proposed in a letter to the Director of Nuclear Reactor Regulation dated Mar' 21, 1978.

D.

Impingement Monitoring, 3.1.2.1.10 The phrase "for a representative number of each species" is added at the end of sentence 1 of the specification.

The remainder of the sentence from "according" through " unit" is deleted.

In the second sentence of the specification, the words "after each day's count" are replaced with the word " monthly" E.

Exposure Panels, Section 3.2.1.1 This monitoring program is deleted.

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F.

Thermal Plume Study, Section 4J The study requirement is deleted since the Thermal Plume Study Report was submitted on April 18, 1979.

G.

Chlorination Stui.y, Section 4.7 The study requirement is deleted since Chlorination Study Report was submitted as part of the 1977 Annual Report.

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3.eason for Change (s)

A.

Seccion 3.1.2.1.5; Benthic Survey INTRODUCTION The ecological monitoring program initiated at Millstone in 1968 included two benthic components:

survey of the rocky shore a

community at five sites, and sampling of the sand infauna at two intertidal locations. The rocky shore survey has continued essentially unchanged since 1969 except for some early more detailed studies of barnacles (Hillman et al, 1973).

The intertidal sand infauna study continued until 1973 when the scope of the entire benthic program increased substantially.

Changes were made subsequent to 1973 was as information was gained.

Results of these studies are best summarized in the 1978, 1977 and 1976 annual reports the NRC.

As the ability to analyze and interpret these data improved, an effcrt was undertaken to evaluate the adequacy of the benthic program in an effor. to maxinize the data given the present level of ef fort and to insure that the program was sufficiently sensitive to the objectives.

Species area curves for sandy substrates showed that the number of individuals and the number of species did not reach an asymtote with the existing level of effort.

Species frequency of occurrence showed that about half of the species in any set of 10 replicate sand samples occurred in only one replicate and that 70% occurred in three or less.

As a result, a special 7 E ')

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i benthic study was initiated to look at differeaces in community parameters as estimated by difference sampling schemes.

The study was specific to sand substrates and addressed sample area (m ) and replication, sample depth, sieve mesh size, and sampling gear.

Conclusions and recommendations were reached based on results of the special study combined with information derived from the l i te ra-ture.

METHODS The Jordan Cove subtidal sand station was chosen for the special study.

Samples were taken in hacch, 1978, during the regular quarterly campling period. A set of ten small cores (10cm in diameter, 5 cm in cepth) and ten large cores (25c,in diameter, 10cm in depth) were taken randomly at the sampling site.

Large cores were placed roughly 0.5-0.75m apart, and all cores were taken within a total distance of Sm.

An atttmpt was made to subsample the large cores into 0-5cm and 5-10cm sections, but this could not be readily accomplished by divers with available sampling gear.

Samples were trans ferred under water to a fine mesh bag and carried to the surface.

A third set of 10 replicate samples was collected with a small grab sampler.

Since the grab did not operate in the coarse sediments at the regular station, samples were taken in an area of fine sed! tents about 50m from the regular station.

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Samples were fixed in 10 percent buffered formaliu, sieved on a 0.71mm mesh screen, and preserved in 70 percent ethanol.

Organisms retained on the screen were sorted from the sediment, identified to the lowest practicable taxon, and counted.

Meiofaunal groups such as nematodes, copepods, ostracods, and kenorhynchs were not included in data analysis, since these groups are undersampled by the screen size used.

Sediment grain size analyses were performed on cores taken subse-quent to saiple collection.

DATA ANALYSIS Species-area curves were constructed for each sam,,le set.

Samples were plotted randomly, and the cumulative number of taxa collected was plotted a;ainst number of replicates (i.e. increasing area) taken.

Taxa were ranked for each sample set according to number of individuals collected, and percentage composition calculated.

Densities per square meter were estimated by applying the appropriate multiplication fcctor to densities per initial sample size.

A t-test was performed 9

on estimated densities per m' of the top ten ranked taxa.

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Community parameters, including the Shannt...,,1ener diversity index, H',

species richness, D; and evenness, J, were calculated for each replicate sample, each set of ten samples, and cumulatively adding 1 through 10 replicates.

Nj N

s j

-f N--

log 7

H' =

where A =1 o

o s = total number of species, N - number of individuals in the A'th species and N = total number of individuals.

g S-1 D = log N where 2

s = number of s,'ecies and N is the numher of individuals.

H' log S 2

H' is the Shannon-Wiener index and log S is the maximum value of 2

H' b..i !

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Hurlburt's rarefaction method (1971) was used as a means of comparing samples of different sizes:

s N-N.+

E(Sn) =

1-

.4 =1 N

n This describes the expected number of species in a sample of n individuale selected at random from a collection containing N individu:a and s specien-Samples were rarefied to 20 individuals.

RESULTS The core samples and grab samples were taken in different substrate types, and therefore in different habitats.

Results of sediment grain size analyses are given in Table 2A-1.

Because two habitats were sampled, direct comparisons between the results of the grab samples and core samples were not made.

However, data from the grab samples are presented.

Species-area curves are given in Figures 2A-1, 2A-3 and 2A-3.

The curve for the large core samples, using all taxa collected (Figure 2A-1) reaches an asymptote at 7 replicates, or 0.35 m surface area.

Six 2

replicates (0.30 m ) collect 94 percent of all taxa collected in 12 replicates.

The curve for the regular (small core) samples does not reach an asymptote.

Ten replicates collected 43 taxa, or 66 percent of the total number of taxa collected in the large cores.

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TABLE 2A-1 -SEDIMENT GRAIN SIZE ANALYSIS OF JORDAN COVE SUBSTRATES

% Composition 2 Composition Core Sample Grab Sample Particle Size Location Location 2+ mm 8.06 4.10 1-2 c:m 12.64 3.47 0.7-1.0 mm 12.23 2.90 0.5-0.7 mm 14.40 8.23 0.297-0.5 mm 25.81 24.41 0.25-0.297 mm 8.58 3.61 0.18-0.25 mm 7.06 2.54 0.125-0.18 mm 2.22 1.13 0.09-0.125 cm 1.08 0.99

<0.09 mm 7.91 48.56

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• Grab Samples

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9 10 Number of Replicates FIGURE 2A SPECIES AREA CURVES USING ALL TAXA COLLECTED IN 10 REPLICATE SAMPLES b,.,

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2----+ Grab Samples

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10 Number of Replicates FIGURE 2A SPECIES AREA CURVES USING ONLY POLYCHAETE SPECIES COLLECTED IN 10 REPLICATE SAMPLES.

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9 10 Number of Replicates FIGURE 2A-3 SPECIES AREA CURVES USING POLYCHAETE-BIVALVE COMPONENT OF ALL TAXA COLLECTED IN 10 REPLICATE SAMPLES.

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The curves based on just the polychaete fraction (Figure 2A-2) or on the polychaete-bivalve fraction (Figure 2A-3) of the taxa collected have shapes similar to the curve based on all taxa (Figure 2A-1).

Tables 2A-2, 2A-3, and 2A-4 give species composition and density estimates for the small cores, large cores and grab samples, respec-tively. Table 2A-5 listt the numerically dominant species in all sample sets.

These tables indicate that trap s;mples and core samples were taken in two different habitats.

Sie finer sediments in Jordan Cove support a fauna similar to that found in Niantic Bay and Long Island Sotnd silty sediments.

Nucula proxima is the numerical dominant in the gra'a samples, and also in previous Niantic Bay collections (Battelle, 1978).

A comparison of the large and small core samples shows both similari-ti<.s and significant differences.

Oligochaeta and Aricidea jeffreysii account for roughly 60 percent of the individuals collected in both sample sets.

However, a t-test performed on estimated average densities per square meter showed a significant difference for Aricidea jeffreysii, as well as for Polycirrus eximius and Polydora caulleryi (Table 2A-6).

The latter two species had very different rankings within each sample set (Table 2A-5), as did Exogone hebes, Tellina agil_is, and Chaetozone so.

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TABLE 2A JORDAN COVE REGULAR (SMALL CORE) SAMPLES: TOTAL INDIVIDUALS COLLECTED, PERCENTAGE COMPOSITION OF TOTAL FAUNA, AND ESTIMATED ABUNDANCES PER SQUARE METER.

(Numbers are based on 10 replicate cores.)

No. of Percent Cum. %

Average Estimate Species

_ Individuals of Total of Total

1. /mZ + S.D.

011gochaeta 313 48.38 48.38 3913 373.9 Aricidea jeffreysii 115 17.77 66.15 1438 1

59.2 Polycirrus crimius 32 4.95 71.10 400

+

33.9 Thary: sp.

26 4.02 75.12 325 t

19.8 L:cnbrineris tenuis 25 3.86 7F.98 313 1

17.6 Ezogone hebes 18 2.78 81.76 225 1

24.5 Cirratulid 15 2.32 84.08 Ltcnbrineris impatiens 9

1.39 85.47 113 17.7 Tel!ina agilis 9

1.39 86.86 113 11.1 Phorocephalus holbolli 6

0.93 87.79 75 1

10.8 Gammarus laurencianus 6

0.93 88.72 75 2

77.8 Parapionosyllis 5

0.77 89.49 63 1

55.9 longicirrata Clycera.Tnericana 5

0.77 90.26 63 5.9 Polydora caulleryi 5

3.77 91.03 63 1

7.9 Corophium acutum 5

0.77 91.80 63 2

7.9 Jassa falcata 4

0.62 92.42 50 1

7.8 Odostomia seminuda 4

0.62 93.04 50 g

14.1 Spionid 4

0.62 93.66 50' 1

4.8 Chaetonone sp.

4 0.62 94.28 50 1

7.8 Capitella spp.

4 0.62 94.90 50 1

5.8 Microphthalmus sczelkovii 3

0.46 95.36 38 t

10.6 Rhynchocoela 3

0.46 95.82 38 1

10.6 Anemone (Burrowing) 2 0.31 96.13 25 4.7 Spio filicornis 2

0.31 96.44 25 2

4.7 Exogone dispar 2

0.31 96.75 25 L

4.7 Nereis acuminata 2

0.31 97.06 25 7.0 Spio sp.

1 0.15 97.21 13 3.5 Polydora quadrilobat2 1

0.15 97.36 13 I

3.5 Microspio spp.

1 0.15 97.51 13 i

3.5 Phy11odocid 1

0.15 97.66 13 1

3.5 Lepidonotus squamatus 1

0.15 97.81 13 1

3.5 Mediomastus ambiseta 1

0.15 97.96 13 1

3.5 Pectincria gouldst 1

0.15 98.11 13

- 3. 5 Exogone t eragera 1

0.15 98.26 13 1

3.5 Ampelisca vadorum 1

0.15 98.41 13 3.5 Cyathura polita 1

0.13 98.56 13 3.5 Modiolus modiolus 1

0 15 98.71 13 3.5 Nucula delphinodonta 1

0.15 98.86 13 3.5 Pandora gouldiana 1

0.15 99.01 13 1

3.5 Terebellid 1

0.15 99.16 13 3.5 Mysid 1

0.15 99.31 13 3.5 Amphiporus spp.

1 0.15 99.46 13 3.5 Total 647 y

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TABLE 2A JORDAN COVE LARGE CORE SAMPLES: TOTAL INDIVIDUALS COLLECTED, PERCENTAGE' COMPOSITION OF TOTAL FAUNA, AND ESTIMATED ABUNDANCES PER SQUARE METER (Numbers are based on 10 replicate cores.)

No. of Percent Cim. %

Average Estimate Species Individuals of Total of Total

1. /m2 + S.D.

Oligochaeta 1226 53.28 53.28 2502 1 380.6 Aricidea Jcffreysii 300 13.04 66.32 612 1 108.3 Lumbrincris tenuis 122 5.30 71.62 249 i 50.5 Cirratulid 120 5.22 76.84 Polydora caulleryi 99 4.30 81.14 202 1 30.4 75 3.26 84.40 153 t 27.6 Tnar g: sp.

Polycirrus crimius 54 2.35 86.75 110 1 21.7 Lumbrineris irpatiens 26 1.13 87.88 53 t 21.7

'lycera americana 23 1.00 88.88 47 1 7.2 c'arapionosyllis 21 0.91 89.79 43 1 17.4 Z 2ngicirrata Chaeto::one sp.

19 0.83 90.62 39 1 8.9 Ecogone hcbes 18 0.78 91.40 37 1 4.6 Tcllina agilis 15 0.65 92.05 31 1 15.0 Rhynchocoela 14 0.61 92.66 29 i 4.3 Spio filicornis 10 0.43 93.09 20 1 3.6 Solcmya valu. :

10 0.43 93.52 20 1 11.0 Capitella spp.

10 0.43 93.95 20 1 12.5 Sabellaria vulgaris 9

0.39 94.34 18 1

11.1 Athenaria sp.

9 0.39 94.73 18 1 6.4 Microphthalmus sczclkooii 8

0.35 93.08 16 t 4.0 Mysella planulata 8

0.35 95.43 16 1 5.4 Nereis acuminata 8

0.35 95.78 16

+

4.0 Spio setosa 7

0.30 96.08 14

[

3.6 Euriida sanguinea 7

0.30 96.38 14 1 5.9 Odostomia seminuda 5

0.22 96.60 10 t

4.3 Phoronid 5

0.22 96.82 10 1

3.1 Pholoc r:inuta 4

0.17 96.99 8

1 3.7 Spionid 4

).17 97.16 8

i 3.1 Ncanthes rirens 4

0.17 97.33 8

+

2.3 Arabella inicolor 4

0.17 97.50 8

[

3.1 Ensis directus 3

0.13 97.63 6

+

3.0 Hediste diversicolor 3

0.13 97.76 6

[

3.0 Maldanid 3

0.13 97.89 6

+

2.1 Driloneris longa 3

0.13 98.02 6

5 2.1 Frotcdorvillca 3

0.13 98.15 6

1 2.1 gaspeensis Lyonsia hvalina 2

0.09 98.24 4

+

2.8 Turbanilla interrupta 2

0.09 98.33 4

1 2.8 Ampalisca abdita 2

0.09 98.42 4

i 1.9 Mediomastus ambiseta 2

0.09 98.51 4

1 1.9 Marphysa bellii 2

0.09 98.60 4

1 1.9 Clycera capitata 2

0.09 98.69 4

i 1.9 Clycera sp.

2 0.09 98.78 Fis ta cristata 2

0.09 98.87 4

i 1.9 Nereis sp.

2 0.09 98.96 4

1 1.9 3 [,2 b)

TABLE 2A (continued)

No, of Percent Cum. %

Avera e Estimate Species Individuals of Total of Total

1. /m + S.D.

nicrophthalmus sp.

1 0.04 99.00 2 1 1.4 Heteromastus filiformis 1

0.04 99.04 2 t 1.4 Dodecaceria sp.

1 0.04 99.08 2 1 1.4 Ncphtys ir.cisa 1

0.04 99.12 2 1 1.4 Orbinia ornata 1

0.04 99.16 2 1 1.4 Schenclais boa 1

0.04 99.20 2 1 1.4 Exoganc dispar 1

0.04 99.24 i t 1.4 Pista maculata 1

0.04 99.28 2 1 1.4 Pista paZmata 1

0.04 99.32 2 1 1.4 Streptosyllis varians 1

0.04 99.36 2 1 1.4 Exoganc verugera

,1 0.04 99.40 2 1 1.4 Epitoniten sp.

1 0.04 e1.44 2 1 1.4 Lacuna vincta 1

0.04 99.48 2 1 1.4 Pitar morrhaana 1

0.04 99.52 2 1 1.4 Marcenaria mercenaria 1

0.04 99.56 2 + 1.4 Erichsonella filifomis 1

0.04 99.60 2 [ 1.4 Jassa falcata 1

0.04 99.64 2 1 1.4 Corophium acutun 1

0.04 99.68 2 t 1.4 Nucula proxima 1

0.04 99.72 2 1 1.4 Nucula delphinodonta 1

0.04' 99.76 2 1 1.4 Pcctinaria gouldii 1

0.04 99.84 2 ~ 1.4 Nerei' 1

0.04 99.80 2 +

1 1.4 Ecconc lactea 1

0.04 99.88 2 +

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TABLE 2A JORDAN COVE GRAB SAFTLES:

TOTAL INDIVIDUALS COLLECTED, PERCENT-IsOE C0liPOSITION OF TOTAL FAUNA, AND ESTIMATED ABUNDANCES PER SQUARE METER.

(Numbers are based on 10 combined grab samoles)

No. of Percent Cum. 7.

Average Estimate Species Individuals of Total of Total

1. /m2 + S.D.

Nucula proxima 168 14.32 14.32 280 1 61.1 011gochaeta 157 13.38 27.70 262 1 54.2 Lumbrineris impaticns 139 11.85 39.55 232 1 40.7 Tcllina agilis 117 9.97 49.52 195 1 48.8 Capitella spp.

100 8.53 58.05 167 1 61.6 Pholoe minuta 47 4.01 62.06 78 1 14.0 Ga":maras laurencianus 42 3.58 65.64 70 1 3C.3 Ncphtys incisa 30 2.56 68.20 50 1 12.2 Mitrella lunata 30 2.56 70.76 50 1 28.5 Maldanid 28 2.39 73.15 47 1 14.9 Crepidula plana 24 2.05 75.20 40 1 30.0 Clyccra americana 22 1.88 77.08 37 1 11.6 Microdeufopus 17 1.45 78.53 28 1 14.9 gryllocalpa Solemya vclum 12 1.02 79.55 20 1

6.4 Asychis clongata 11 0.94 80.49 18 1

5.4 Chaetozone sp.

10 0.85 81.34 17 i

5.9 Corophium acutum 10 0.85 82.19 17 t

6.5 Erichsonella filiformis 10 0.85 83.04 17 1 11.2

/.thenaria sp.

10 0.85 83.89 17 1

5.3 Crepidala fornicata 9

0.77 84.66 15 11.3 Aricidea jeffreysii 8

0.68 85.34 13 1

3.6 Cirratulid 8

0.68 86.02 Harmathoc extenuata 7

0.60 86.62 12 2

.7. 5 Polydora quadrilobata 7

0.60 87.22 12 2.7 Chirodotea caeca 7

0.60 87.82 12 5.0 Turbanilla interrupta 7

0.60 88.42 12 2

5.0 Yoldia sp.

7 0.60 89.02 12 5.3 Unciola irrorata 6

0.51 89.53 10

+

4.2 Nucula delnhinodonta 6

0.51 90.04 10 t

3.3 Mediomastus ambiseta 5

0.43 90.47 8

+

2.1 Polycirrus e=imius 5

0.43 90.90 8

1 3.4 Ampelisca verrilli 5

0.43 91.33 8

1 5.0 Retusa canaliculata 5

0.43 91.76 8

~

2.8

+

Microphthalmus sczelkooit 5

0.43 92.19 8

2 3.4 Rhynchocoela 4

0.34 92.53 7

1 2.0 Ampetisca vadoru, 4

0.34 92.87 7

t 2.0 Corophi:c, insidiosum 4

0.34 93.21 7

t 5.0 Neopanope tcrana 4

0.34 93.55 7

i 5.0 4

0.34 93.89 7

1 5.0 Clymenella torquata Phyllodoc.. arenae 3

0.26 94.15 5

1 1.9 Eumida sanguinca 3

0.26 94.41 5

1 2.7 Erogone hebes 3

0.26 94.67 5

1 1.9 Maccna tc-ta 3

0.26 94.93 5

1 2.7 Odostomia ceminuda 3

0.26 95.19 5

2 2.7 Nassarius trivir.tatus 3

0.26 95.45 5

t 2.7 Anadara transuctsa 3

0.26 95.71 5

2 2.7 Nephtys picta 3

0.26 95.70 5

1.9

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TABLE 2A (continued)

No. of Percent Cum. %

Average Estimate Species Individuals of Total of Total

1. /m2 + s,p.

Arabella iricolor 2

0.17 95.87 3

i 1.7 Lumbrincris tenuis 2

0.17 96.04 3

t 1.7 Scoloplos acutus 2

0.17 vi

3 1

2.5 Lepidonotus squamatus 2

0.17 96.38 3

1 2.5 Leptocheirus pir-Juis 2

0.17 96.55 3

2 2.5 Ensis directus 2

0.17 96.72 3

1 2.5 Cema gema 2

0.17 96.89 3

1 2.5 Pho ronid 2

0.17 97.06 3

1 1.7 Driloneris longa 1

0.09 97.15 2

1 1.2 Cirrifomia grandis 1

0.09 97.24 2

2 1.2 Protodorvillea gaspcensis 1

0.09 97.33 2

1 1.2 Flabelligera affinis 1

0.09 97.42 2

1 1.2 Ninoc nigripes 1

0.09 97.51 2

1 1.2 Ampharcte arctica 1

0.09 97.60 2

1 1.2 Narcis acu~:inata 1

0.09 97.69 2

1 1.2 Neanthes vircns 1

0.09 97.78 2

t 1.2 Diopatra ca;.

1 0.09 97.87 2

1 1.2 Paraonis gracilia 1

0.09 97.96 2

t 1.2 Pcetinaria gouldii 1

0.09 98.05 2

1 1.2 Etconc lactea 1

0.09 98.14 2

1 1.2 Sthenclais limicola 1

0.09 98.23 2

1 1.2 Brania claoata 1

0.09 98.32 2

1 1.2 E.rogonc verugcra 1

0.09 98.41 2

1 1.2 Terebellid 1

0.09 98.50 2

1 1.2 Pscadomalacoccros sp.

1 0.09 98.59 2

1 1.2 Euratella sp.

1 0.09 98.68 2

1 1.2 Lambos ocbsteri 1

0.09 98.77 2

+

Jassa falcata 1

0.09 98.36 2

~

1.2 1

1.2 Unciola serrata 1

0.09 98.95 2

i 1.2 Cynaduca sculpta 1

0.09 99.04 2

1 1.2 Balarius balanoides 1

0.09 99.13 2

1 1.2 Crangon septcmspinosus 1

0.09 99.22 2

t 1.2 Yoldia linatula 1

0.09 99.31 2

i 1.2 Ha :inoea solitaria 1

0.09 99.40 2

1 1.2 Nysella planulcia 1

0.09 99.49 2

1 1.2 Anachis lafresnayi 1

0.09 99.58 2

1 1.2 Pitar morrl 2na 1

0.09 99.67 2

1 1.2 Carithiopsis greeni 1

0.09 99.76 2

1 1.2 Astcrias sp.

1 0.09 99.85 2

1 1.2 Nereidae 1

0.09 99.94 2

+

1.2 Total 1173

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TABLE 2A DOMINANT SPECIES IN SPECIAL BENTHIC STUDIES SAMPLES Rank in Percent Total Fauna in Species Regular Core /Large Core / Grab Regular Core /Large Core / Grab ~

011gochaeta 1

1 2

48.38 53.28 13.38 Aricidca Jeffreysii 2

2 21 17.77 13.04 0.68 Polycirrus crimius 3

6 29 4.95 2.35 0.43 Thary: sp.

4 5

4.02 3.26 0

Lumbrineris tenuis 5

3 47 3.86 5.30 0.17 Erogone hebes 6

1]

39 2.78 0.78 0.26 Lu.~;brineris Vpatiens 7

3 1.39 1.13 11.85 Tellina agilis 12 4

1.39 0.65 9.97 Pharacephalus halbolli '

0.93 0

0 9

Ga marus laurencianus 7

0.93 0

3.58 Polydora caulleryi 4

0.77 4.30 0

Clyccra c":cricana 11 8

12 0.77 1.00 l'.88 Parapionosyllis 9

0.77 0.91 0

longicirrata Chacto::ane sp.

15 10 16 0.62 0.83 0.85 Nucula promina 61 1

0 0.04 14.32 Ccpitella spp.

(15) 14 5

0.62 0.43 8.53 Pholce minuta 6

0 0.17 4.01 Nephtys incisa 43 8

0 0.04 2.56 Mitrella lunata 9

0 0

2.56 Maldanid 30 10 0

0.13 2.39 iE)

(2k

2 TABLE 2A T-TEST BASEL ON ESTIMATED DENSITTES PER m Taxa Regular Large Diff.

t 011gochaeta 3912.5 2452.0 1460.5 1.02 Aricidea Jeffreysis 1437.5 600.0 837.5 3.20*

Polycfrrus crimius 400.

108.0 292.0 2.35*

325.0 150.0 175.0 2.15 Thar"j sp.

Lumbrineric tortis 312.5 24,.0 68.5 0.72 Exogone hebec 225.0 36.0 189.0 2.17 Lumbrincris impatiens 112.5 52.0 60.5 0*

Tellina agilis 112.5 30.0 82.5 1.6%

Phazocephalus halbolli 75.0 0.0 75.0 Gc:~arus laurencianus 75.0 0.0 75.0 Polydora caulleryi 62.5 198.0

-135.5 2.61*

Glycera americana 62.5 46.0 16.5 0.71 Parapianosyllis longicirrata 62.5 42.0 20.5 0.63 G'r.ac toconc sp.

50.0 38.0 12.0 0.39

• Significant at the.G5 level.

.. c, ->

(

Several species were collected in the large core samples but not in the small core samples (Table 2A-7).

This is primarily a function 2

2 of the larger total surface area collected (0.5 m vs. 0.078 m ), but a second factor is the greater depth to which the large cores were taken.

For instance, several of the polychaete species listed in Table 2A-7 are large, motile, often deep-feeding forms.

These include Nephyts incisa, Heteromastus filiformis, maldanids, Neanthes yi cens, Driloneris longa and Orbinia ornata.

These species have been taken in previous collections at Millstene Point (Battelle, 1978) but possibly not in representative numbers.

Table 2A-8 presents taxa enumerated in the small core sample set, but not found in the large cores.

Most infaunal organisms are patchily distributed (Jones, 1961) and chance plays a large role in which species will be collected by relatively small sample sizes.

Values for H',

D and J are given in Teble 2A-9.

These values are cumulative over the sample set, starting with one core at the left of the table, and finishing with all 10 corer at the right. That is, the first column gives values based on one core or grab, column 2 gives values on two cores, column 3 on three cores, and so on.

The most obvious trend is the decrease in variance associated with the H' statistic, indicating an increasing level of accuracy in the calucation.

The H' value itself changes slightly as cores are added, tl'e basic trend being an increase in the value as cores are added.

Although the value for H' is similar for the entire sample set of small cores (2.90) vs. large cores (2.70), it should be b

2-7

TABLE 2A SPECIES FOUND IN LARGE.JRES, NOT FOUND IN REGULAR CORES Polychaetes Eumida sanguinea Etconc lactea Arabella iricolor Photoe minuta Neanthcc virena Drilonaris longa Maldanid M2rphysa belli Protodorpiilca gaspeensis Glycera capitata Pista cristata Nercis sp.

Spio setosa Sabellaria vulgaris Heteromastus filiformis Microphthalmus sp.

Dodccaceria sp.

Nephtys incisa Orbinia ornata Sthanelais boa Pista maculata Pista cristata Streptocyllie varians (Nereid)

Molluscs soic=ya velum Athenaria sp.

tysella planulata E: sis directus Lyonsia hyalina Turbanilla interzupta Epitonium sp.

bacuna vincta Pitar marrhuana

!!crcenaria merecnaria Nucula proxima Arthropods Ampelicca abdita Erichsonella filiformis Other Phoronid

, h J J (-

L', ' t

TABL2 2A SPECIES FOUND IN REGULAR CORES, NOT IN IJ.RGE CORES Polychaeta Polydora quadrilobata Microspio sp.

Spio sp.

Lepidonotus squa":atus Phyllodocid Terebellid Mo11uses Modiolus modiolus Pandora couldiana Arthropods Phoxoccphalus hoibeili Gamarus laurencianus h,,)elisca vadorum Cyathura polita Mysid Others Anemone, burrowing Amphiporus sp.

6 L;

9.,

r

> d b 45 )

04 23 96 s3 73 67 35051 0

08013 05075 50027 90055 70074 1

20040 20050 40080 1

1 5 13 26 93 73 95095 85052 89 9

69025 50027 60074 80005 1

20050 40080 20040 SETAC I

07 L

62 35 13 P

63 56052 E

75 25023 R

8 40191 50007 11095 60094 0

1 20050 40080 30030 1

NO D

40 E

7 3 13 05 S

3 12 87046 B

7 4 1120 9!055 A

01086 60094 60037 S

1 20050 40070 30030 FL PM A

S 40 96 42 76 C

93 H

6 92172 25024 87018 35 I

60077 91046 60074 T

N 1

20050 40060 20030 EB EVO 53 C

00 35 96 34 N

83163 06033 67008 27 A

5 50034 60067 91036 D

20030 20050 40060 R

1 O

J FO 26 S

44 75 16 R

64 26022 08058 99 ET 4

93192 60047 E

81 016 40004 M

1 20050 40060 20030 ARA P

L 77 A

60 43 77 C

37 20 98059 T

3 94284 18005 I

50017 S

91 036 40014 I

1 20040 40060 20030 TAT S

E 50 V

75 84 68 I

38 95 51120 T

15242 39061 11058 A

2 60005 L

71 006 20030 20040 40040 U

1 M

U C

09 86 96 77 45 36291 83 30449 92107 11087 9

22025 6107 3 1

30020 s

A e 20020 10020 2

r se s

o e

C r

e E

r e

o e

L o

r c

C c

s c

l n

e n

lA C

a n

l a

T l

a e

a f

A u

.i B, g

.i Cb p

.i r

am D. ar D.

ra r

o g

D. r a

a

?.

R

'H S V D J L

'H S V D J GS HSVD1 e

a

pointed out that the upper limit of H' is set by the total number of species collected; therefore, the largest possible value of II' for the smalI cores is lower than the largest possible value of H' for the large cores.

Results of t he rarefice. ion are presented in Table 2A-10.

Each sample collected consisted of a oifferent number of individuals, partly because sanple sizes were differenct (small vs. large core) and partly due to the element of chance associated with collecting patchily distributed individuals with small sampling devices.

DISCUSSION AND CONCI ' IONS Based on the species-area curvas generated in this stuc it appears that the total surface area currently collected, 0.078 m undersamples much of the infaunal community.

The curve based on the large cores reaches an asymptote only when 0.35 m have been collected.

Six replicates, or 0.3 m, collected 94 percent of all species recorded.

This is nearly four times the current sample size requiring forty of the 10cm diameter cores.

Large grab s.mples which cover areas 2

greater than 0.05 m are available (Smith-McIntyre, 1954) but do not function well in coarse sediments.

If a coring device is used, there will be an upper limit on size due to difficulty in handling by divers. The large core used in this study was 25cm in diameter and also presented some difficulties to the collectors.

r, ]

.)

..,) l L

{" '/ -

/

J 2-8

TABLE 2A-10-NUMBER OF TAXA IN ORIGINAL SAMPLES AND MIEN EARE Sample Nunber 1

2 3

4 5

6 7

8 9

10 S.D.

x Reguler Cores Original 14 12 10 10 11 11 15 13 14 22 Rarefied 7

8 8

7 9

7 8

9 5

7 7.51 1.2 Large Cores briginal 23 24 17 27 22 27 18 22 22 15 Rarefied 5

8 4

6 8

8 8

5 7

7 6.61 1.5 Grab Samples 0.iginal 21 26 33 26 15 20 18 33 20 18 Rarefied 8

11 11 10 il 10 10 9

10 7

9.71 1.3 4

0

A facter which bears on the selection of a sampling device is the mesh size of sieves used to process the sand samples.

A trade-off exists between sieve screen size and amount of surface area necessary to characterize the infauna.

Investigators who compared organisms retained on screens of different mesh sizes have shown that many organisms, particularly polychaetes, are lost on coarse meshes (Reish, 1959; Sanders, et al., 1962; Knox, 1977T.

Knox (1977) reviews the data available on numbers of species and individuals retained on screens of different mesh sizes.

Use of a scrten larger than 0.5mm mesh can result in a loss of from 20 percent (using 0.7mm) to 80 percent (using 2.0mm) of the individuals present in the sample. Not only Knox, but Holme and McIntyre (1971) utge that benthic studies routinely use a 0.5mm screen.

Work done by Sanders (1978), Grassle and Grassle (1974), and Grassle (1977) suggests that the minimum area thnt should be sampled is 0.1 m using a 0.5mm screen. At Millstone, this would require that we collect about 15 small 10cm diameter cores at each sampling.

Based on the information presented above, a modified benthic program is proposed as shown in Attachment 1 Revised ETS Section 3.1.2.1.5.

Samples will be sieved through a.5mm mesh screen.

A total combined surface area of 0.1 m is specified.

It has been shown that surface area sampled is the more important criteria for adequcte characteriza-tion of benthic communities. The sample core size and the number of replications is not detailed inorder to provide sufficient flexibility in the future choice of sample devices.

Our intent

Fq

{' O tj

,) J L 2-9

initially is to employ the 10cm core currently being used and to take a total of 15 replicates at each station per sampling (0.12 m ).

Additional support for this arrangement is provided by Gage and Coghill (1977) who demonstrated several small cores can provide statistically more precise information on infaunal communities than two or three replicates of a large grab sample.

Certain of the sand stations have also been deleted in an effo-t to keep the total number of samples at existing levels.

The existing ETS program with nine sand stations and 10 replicates yields 90 samples per quarter as does the proposed program with six stations and 15 replicates.

Only those stations sufficiently close in to the power station to represent areas of impact have been retained with the exception of Giants Neck which remains a control location.

Bay Point and Little Rock subtidal sand stations are felt to be redundant in terms of their location and are replaced with a station adjacent to the cooling water intakes.

This location has been sampled since 1976 even though it is not shown in the existing specification.

With respect to the sandy substrates, it is felt that the proposed program will be of sufficient scope to adequately characterize benthic communities according to current standards and will improve our ability to evaluate changes that may be due to the effects of power plant operation and construction.

2-10 a

Finally, it should be noted that all samples of tocky substrates have been deleted from this specification. We have found that biomass sampling at many of the stations removes a

gnificantly large percentage of available habitat each quarter.

Therefore, these collections are more a measure of settlement and recolonization after three months than they are a measure of long-term power plant impacts.

Since it takes over two years for a surf ace scraped clean to return to equilibrium, no organisms are exposed to the effects of plant operation for more than three months.

Further, studies of rocky shore habitats will be continued as part of the intertidal rocky shore survey (ETS Section 3.1.2.1.2).

It is felt that these studies, in existence since 1968, will be suffi-cient to assess power plant impacts on rock habitats.

Subtidal rock is not included in this program since it is not a major habitat type in the Millstone area.

2, [ ^ '>

3- -

sJL l'i,I 2-11

LITERATURE CITED Battelle.

1973.

A Monitoring Program on the Ecology of the Marine Environment of the Millstone Point, Connecticut Area.

Summary Report for 1973 to Northeast Utilities Service Company.

Battelle-Columbus Laboratories, William F. Clapp Laboratories, Inc.,

Duxbury, Massachusetts.

Battelle.

1978. A Monitoring Program on the Ecology of the Marine Environment of the Millstone Point, Connecticut Area.

Annual Report for 1978 to Northeast Uti'ities Servic' Company.

Battelle-Columbus Laboratories, W. F. Clapp Laboratories, Inc., Duxbury, Massachusetts.

Gage, JD. and G.G. Coghill.

1977.

Studies on the dispersion patterns of Socttish Sea Loch benthos from continguous core transects.

_I n :

Ecology o_f Marine Benthos.

B. Coull (ed.) Belle Baruch Library in Marine Science.

No. 6.

Grassle, J.F. and J.D. Grassle.

1974.

Opportunistic life histories and Genetic Systems in Marine Benthic Polychaetes.

J. Mar. Res.

32:

253-284.

Grassle, F.

1977.

Slow recolonization of deep-sea sediment.

Nature.

265:

618-619.

Holme and McIntyre.

1971.

Methods for Studying the Marine Be.nthos.

Int. Biol. Prog. Handbook No. 16.

Blackwell Scientific Eublications, Oxford 334 p.

Hurlburt, S.H.

1971.

The nonconcept of species diversity:

A cirtique and alternate parameters. Ecology.

52:577-586.

Jones, M.L.

1971.

Knox,,g,,1977.

Importance of polychaetes in soft bottom benthic communities.

In:

Essays on Polychaetous Annelids in Memory of Dr. Olga Hartman.

Alan Hancock Foundation, University of Southern California.

Sanders, H.L., E.M. Geudsmit, E.L. Mills, and G.E. Hampson.

1962.

A study of the intertidal fauna of Barnstable Harbor, Massachusetts.

Limnol.

Oceangr. 7:

63-79.

Sanders, H.L.

1978. Florida Oil Spill Impact on the Buzzards Bay Faune-West Falmouth.

J. Fish. Res. Bd. Can. 35:

717-730.

Shannon, C. and W. Wiener.

1949.

The mathematical theory of ccmmunication.

Univ. of Illinois Press.

126 p.

Smith, W. And A. D. McIntyre.

1954.

A spring-loaded bottom sampler.

J. Mar. Biol. Ass. U.K.

33:

257-264.

Reish, D. J.

1959. A discussion of the importance of screen size in washing quantitative marine bottom samples.

Ecology 40:

302-309.

2-12

'l

? c ')

\\,

B.

Trawl Survev, Section 3.1.2.1.7 Figure 3.1.2 is no longer applicable to the Plankton program since the study requirement was satisfied and has been deleted from the ETS.

Ilowever, the figure is still applicable to the trawl program.

Only those stations sampled by other trawl have been left rn the figure as modified, namely 2, 5, 6, 8, 11 and 17.

The objective has also been changed to be consistent with the specification. Since no weight measurements are taken, condi-tion factors cannot be calculated.

Also, any information gathered on reproductive activity would be subjective since ovaries are not examined quantitatis21y.

7(

'~)

dJl

(',.

)

2-13

C C.

Entrainment Studies, Section 3.1.2.1.9 Analysis of existing data demonstrates that entrainment analyses are essentially uneffected by the reduction n sampling effort.

The present environmental technical specifications Section 3.1.2.1.9 specify that for the icthyoplankton entrainment studies "three samples shall be taken both day and night three days per week."

These 18 samples per week over the last two and one-half years have pro-vided information for estimating ichthyoplaakton abundances that are more than adequate to meet the objective of the entrainment studies".

to quantify the zooplankton (including fish eggt and larvae) that pass through tne plants.

The samples collected in the months of October, November, and December typically contain low numbers of fish eggs and larvae and have not provided as much quantitative information on major entrained ichthyoplankton as samples collected during other months.

It is proposed that a two-thirds reduction in the number of samples collected in these fall months would not seriously affect the ability to meet the objectives of the entrainment studies.

Supporting analyses provided herein to demonstrate the small changes produced in response to a reduction of the fall effort from 18 to 6 (3 day and 3 might) samples per week are based on 1975, 1976 and 1977 data.

The procedures used for the collection and processing of ichthyo-planton samples have been documented (NUSCO, 1977).

The " reduction" of fall sampling effort was simulated by including a given analysis only the first three days and first three night samples callected in any week in October, November or December.

The analyses. included J-L L

2-14

consideration of changes in such charactaristics as the annual rank order, percent species composition and abundance estimates particu-larly for " import ant species." Such species were considered to be those of particular interest to local commercial or sport fisheries such as (Pseudopleuronectes americanus, Scomber scombrus, f3 revo rt i a tyrannus and Tautoga onitis) or have a potentially significant relationship to the regional ecology due to + heir relative importance in the species composition such as (Anchoa sp., Ammodytes sp.,

Myoxocephalus sp., and Tautogolabrus af.persus).

All of the species listed have represented greater than 5% of the percent species composition in at least one of the last three years (NUSCO., 1977).

Ifistorically, the weekly estimates of total ichthyoplanktcu abundance 3

(#'s/m ) have been lowest each year in October, November and December (Figure 2C-1).

Also. "imoortant species" have not been fotro in maximal abundances during these months (Figure 2C-2).

For thea.

reasons, a reduction of the number of fall samples for 1975, 1976 and 1977 produced little change in the annual rank order for the top 21 species of those years (Tables 2C-1, 2C-2 and 2C-3).

Spearman's rank correlation coef ficient, Rs, of the two rankings for each year were 0.998, 0.94 and 0.99 for 1975, 1976 ond 1977 respectively.

These coefficients indicated that the tanking prduced by considering all of the samples were the same for statistical purposes.

The annual pe rcent species composition and average annual abundance are the two most important factors in considering the reduction of fall samples since the quantitative entrainment estimate for each

!b 2-15

7= 1977 7

7.2 6= 1976 5 = 1975

/

6.4 6

5.6

/

6 4.6

[

( 4.0 O

t.

6 m

N 7

g 3.2 E

s:<

?ou s

6 6 6

'a ~*1, 6 6

7 7

( ~, _.

7 6

0.8

-j 6

6 6 6 j

,y 7

7 7 6

7

/

7 7

7 7

7 7 6 7 7

1 7 7 7 7

5 6 6 rs, 7

7 7 7 6 7 6 6 6 6 6 6 6 7

5 56 6 7

7 6 5555555555 55555 6 5 6 0.0 6 6 6 6 6 6 6

- i J

F M

A M

J J

A S

O N

D MONTH Weekly abundance of totai 'chthyoplar.cton in entrainment samples collected at the Millstone FIGURE 2C-1 Units 1 and 2 discharges in.375, !976 and 1977.

SPECIES J

F M

A M

J J

/

S 0

N D

1975 RBKwdrs e F iIrsmWJ L

Amadytee sp.

1976 RMreAn7e?W A%iiv7anan W

M 1977 Mhvandt V M "R E,T m T"?

ymi'f4MJ<Ata JWh*WLiewceratAX 1975 EETDUT2%8SER'7BWAVPhtDBRJL 7a Tr Anchoa sp.

1976 wh M

i

+4. i 1 5 IW

&MKSGATMEQ FCm fG"M MLNs b B. tyrannue 1976 WLN er25 1977 Rj r m ? % N da tir m u H IGrmP'S +

1975 p r W 4u4 #t M T e m N4 G mvVEn%YE:

acwrb&

+jo ocephatue ep.

1976 1

3 1*3rt.7pm; t vrA P. arwricanus 1976 f.eGKhiDN2%T3%VrJTWGDLFsMi4 WIN 2 1977 FAE*QSAF$qjg*U' WCLhM41i 2 hTHWWtW:t: R 1975 S. scorrbrus 1976 Wi^iMR W t i975 MMa cM.

WTNTisWusMFM T. adepereus 1976 2

19 imPWJDrst4malimiu T. ndtie 1976 E M3M9NN NJAL W 4 1977 FIGURER 2G-2 Periods of occur;ence and peak abundance (0) over last 3 years for the important species found in Millstone Nuclear Power Station entrainment samples y(,

~ ) < l.

(_

l

\\

TABLE 2C Rank order,1975, based on all samples co11scted and on a reduction to one 5

-d of the present fall effort.

SPECIES FALL 1/3 FALL 1

1 l.nchoa sp.

P. amricanus 2

2 3

4 B. tyrannus S. ecombrue 4

3 5

5 Amadytes sp.

6 6

L^gorocephalus sp.

7 7

T. adspersue 8

8

5. aquoeus T. cnitis 9

9 10 10 S. fuscus P. gunneIZus 11 l '.

Gobiidae 12 12 Unidentified 13 13 P. triancanthus 14 14 15 15 Menidia sp.

16 16 U. eubbifurcata 17 17 S. chrysops 18 18 Prionotus ep.

E. cir:brius 13 19 20 20 C. regalis 21 21 Liparis sp.

}

ow o.

I,

~u-

TABLE 2C-2 -Rank order,1976, based on all earples collected and on a reduction to one-third of the present fad effort.

SPECIES 3/3 FALL 1/3 FAl.L P. americanus 1

1 2

2 Anchoa sp.

3 3

A-nodytes sp.

4 4

1. gozocephalus sp.

5 5

P. gunneilus 6

6 S. aquosus U. subbifurcata 7

7 8

9 B.

tyrannus 17 Cobiidae 9

8 Unidentified 10 E. cimbrius 11 10 T. onitis 12 11 13 12 T. adspersus 14 15 S. fuscus 15 13 Liparis sp.

16 14 A. rostrata P. triancanthus 17 16 18 21 Menidia sp.

19 18 P. oblongus 20 19 L. ferruginea 21 20 Urophycia sp.

.) a (-

L.,

1 '

d

Rank order,1977, based on all samples collected and on a reduction to TABLE 2C one-third of the present tall ef fort.

1/3 FALL 3/3 FALL S?ECIES 1

1 Amadytee op.

2 2

Anchoa ep.

3 3

P. americanus 4

4 h*go:ocephalue ep.

5 5

P. gunneilue 6

6 Unidentified 7

7 S. q w sue 8

8 Liparis ep.

9 9

T. adspercus 10 10 S. fuscus 15 11 Codiidae 12 11 A rostrata 13 12 T. onitie 13 14 S. ecombrus 14 15 F. ein:brius 16 16 B. tyrannue 17 17 U. subbifurcata 18 18 C. harengue 19 19 P. triacanthus 20 20 S. chrysope 21 21 Prionotue ep.

\\

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U r

)J b

species h.i s licen genci a t est t>y mu t t a i>l y ing nici t ent :. iici i c: s i.mi..n son by total number of larvae entrained.

Tables 2C-4 through 2C-6 show that percent species composition and mean annual abundance are affected very little by a reduccion in effort to one third. The greatest change in abudance occurred with the Gobiidae (less than 3%), a group that has been more important in the fall months but relatively insignificant over the year.

Given that the parameters used to demonstrate the quantity of ichthyo-plankton entrained (percent species composition, annual abundance es-timates) are changed little by the simulated fall reduction, it is fe t that our ability to meet objectives specified in the technical specifi-cations would be essentially uneffected by reducing the fall effort to one-third of the present level.

LITERATURE CITED NUSCO., 1977.

Annual report, ecological and hydrographic studies, P. O. Box 270, Hartford, CT 06101.

-f

,~, n 1 2-16

)rqsL L 't

Percent species composition and abundance estimates 1975, based on all TABLE 2C samples collected and on a reduction to one-third of the present f all ef fort.

s Fercent Composition Abundance (#/m )

2pecies 3/3 FALL 1/3 FALL 3/3 FALL 1/3 FALL 61.96 62.35 0.100 0.126 Anchoa sp.

P. americanus 7.71 7.88 0.093 0.093 6.13 5.42 0.021 0.028 B. tyrannus S. scombrus 5.45 5.58 0.210 0.210 2.68 2.70 0.032 0.037 Ammodytes sp.

jfjorocephalus sp.

2.46 2.51 0.034 0.034 2.04 2.09 0.022 0.022 T. adspersus 1.93 1.89

0. 01(,

0.011 S. aquosus T. onitis 1.74 1.79 0.015 0.015 1.29 1.30 0.006 0.006 S. fuscus P. gunneZZus 1.00 1.01 0.020 0.022 Gob 11dae 0.98 0.95 0.005 0.005 Unidentified 0.80 0.82 0.007 0.007 P. triacanthus 0.54 0.55 0.006 0.006 Nanidia sp.

0.52 0.53 0.008 0.008 U. subbifurcata 0.43 0.44 0.018 0.018 S. chrysops 0.36 0.37 0.008 0.008 Prionotus sp.

0.28 0.29 0.006 0.006 E. cir:brus 0.27 0.28 0.008 0.008 0.20 0.20 0.006 0.006 C. regaZis Liparis sp.

0.17 0.18 0.011 0.010 E2 Di2

, s n t m a,

= -

Percent specie 9 composition and abundance estimates 1976, based on all

.. r i... i t.....:..a

....:., 4 -. ~.,wa,,a rs

,w.

r....

, s.15

,grr,,.

Percent Composition Abundance (#/m')

3/3 FALL 1/3 FALL 3/3 FALL 1/3 FALL P. caricanus 30.34 32.67 0.106 0.106 Anchoa sp.

26.,75 27.34 0.045 0.048 Amodytes sp.

14.92 12.82 0.039 0.036 Ryozocephalus sp.

6.21 6.69 0.019 0.019 P. g:c:ncIlus 4.39 4.73 0.021 0.021 S. aquosus 2.60 2.74 0.012 0.013 U. subbifurcata 2,06 2.22 0.016 0.016 B. tymnnus 2.02 1.18 0.009 0.007 Gobiidae 1.75 0.45 0.012 0.005 Unidentified 1.37 1.36 0.005 0.005 E. cimbrius 1.03 1.11 0.009 0.009 T. onitis 0.98 1.05 0.006 0.007 T. adspersus 0.79 0.85 0.007 0.007 S. fuscus 0.73 0.67 0.004 0.004 Li,aris sp.

0.71 0.77 0.007 0.007 A. roserata 0.65 O.69 0.007 0.007 P. triacanthus 0.43 0.46 0.005 0.005 Menidia sp.

0.27 0.18 0.004 0.004 P. oblongus 0.24 0.24 0.004 0.006 L. ferruginea 0.18 0.20 0.006 0.006 Urophycis sp.

0.18 0.19 0.003 0.004 7 f "1 JJ(

n f} J

TABLE 2C Percent species composition and abundance estimates 1977, based on all samples collected and on a reduction to one-third of the present fall ef fort.

Percent Composition Abundance (#/m')

3/3 FALL 1/3 FALL 3/3 FALL 1/3 FALL A-modytes sp.

31.33 30.17 0.089 0.085 Anchoa sp.

27.80 27.76 0.071 0.080 P. americanus 8.62 9.25 0.048 0.048 Mgorocephalus sp.

6.74 7.22 0 028 0.029 P. gunne!Ius 4.33 4.64 0.024 0.025 Unidentified 3.39 3.48 0.010 0.010 S. aquosus 2.62 2.65 0.013 0.014 Liparis sp.

2.32 2.48 0.023 0.023 T. adspersus 2.06 2.21 0.022 0.022 S. fuscus 1.80 1.80 0.008 0.009 Gobiidae 1.64 0.83 0.011 0.009 A. rostrata 1.16 1.25 0.014 0.014 T. onitis 1.16 1.24 0.009 0.009 S. scombrus 0.92 0.99 0.017 0.017 E. cimbrius 0.89 0.95 0.011 0.011 B. tyrannus 0.77 0.57 0.006 0.005 U. subbifurcata 0.46 0.49 0.009 0.009 C. harengus 0.29 0.27 0.005 0.005 P. triacanthus 0.25 0.27 0.004 0.004 S. chrysops 0.22 0.24 0.006 0.006 Prionotus sp.

0.17 0.19 0.004 0.004

}t]2

( !! !I

D.

Impingement Monitoring, Section 3.1.2.1.10 The proposed ETS change for impingement monitoring deletes the requirement to place fish and shellfish lengths into categories and also places the cumulation of 24-hour counts on a monthly basis instead of after each day's count.

The three length categories (0-3", 3-6" and >> 6") were used as a matter of convenience when impingement monitoring was carried out in earlier years.

Iloweve r, in examining the impact of impingement on local populations, it is more appropriate to use actual length measurement: which can be apportioned in any number of increments.

Length measurements of a representative number of each species impinged have been made at Millstone since early 1975.

Using length measurements which have some biological implication such as age, it is now possible to compare length of impinged fish with those collected in other sampling gear.

It is felt that this kind of data greatly improves our ability to make impact assessments more meaningful.

The second change whereby cumulative totals are to be made on a monthly basis siraply allows more latitude with respect to data handling.

The basis for a daily cumulative historically was to maintain a running total which could be compared to report limits.

The absence of such limits removes the immediacy of daily cumulatives.

The 24-hour totals for each species will signal an important impinge-ment event should one occur.

5 2-17

E.

Exposure Panels, Section 3.1.2.1.1 Exposure panels have been used at Millstone Point since 1968 to assess the impacts of construction and operation of the power plants on marine boring and fouling communities in nearby Long Island Sound.

The panel program now represents over ten years of ecological monitoring data.

Methods and results are reported in numerous annual reports and in the scientific literature (Battelle, 1979 and 1978; Hillman, 1975; Hillman et al, 1973).

Results, to date, indicate that construc-tion and operation of the Millstone Nuclear Power Station have had no measurable impact on marine boring ar.d fouling communities observed on the panels in Long Island Sound.

There has been a generalized trend toward increased numbers of species, parti-cularly algae, over the years.

This trend has been noted at stations located adjacent to Millstone Point and at others more remote.

Improved water quality conditions, and/or improved taxonomic expertise are suggested as contributing factors (Battelle, 1979 and 1978).

The 1978 annual report, for example, summarizes the number of taxa occurring on long-term panels over the study period (Figure A-3, Battelle, 1979).

In 1968, the number of taxa ranged between 23 taxa on panels in the Millstone Harbor and 29 at White Point. The numbers increased steadily at most stations until 1974 and apparently leveled off thereaiter although there was considerable variation between stations.

A 0@o 2-18

peak of 71 taxa was reached in 1976 at White Point.

The range in 1978 varied between 40 taxa at the effluent and 65 at White Point.

The total number of taxa on all panels has also varied widely f rom year to year although the program ef fort has been fixed since 1973.

The totals for the years 1973 through 1978 were 247, 321, 304, 226, 254 and 245 taxa respectively.

Given this variation in numbers of taxa, the dominant forms were ubiquitous over time and space.

These conclusions are supported by intensive reviews of the data made not only by W. F. Clapp Laboratories but also by the Massachusetts Institute of Technology (MIT).

Since the exposure panel program represented a significant time series of ecological monitoring data, Northeast Utilities began, in 1975, to carefully evaluate the information being obtained trom the program.

The Energy Laboratory of MIT was awarded a two year research contract.

Their charge was to identify, develop and carry out alternative analyses of panel data in order to maximize the information derived.

Brown and Moore (1977) detailed the findings and conclusions of this study (Attachment 2).

Briefly, they conclude that exposure panels yield data relevant to hypotheses testing regarding environmental effects of power plant cooling water intake and discharge.

The most meaningful 7Cn p f ~j JJL 2-19

parameter from the present program is the number of species occurring on 12-month panels.

Also important is the conclusion that the lack of replication restricts the use of standard statistical tests and further that "the collection of replicate samples could significantly improve the sensitivity of all methods of analysis" Based on this conclusion, W. F. Clapp Laboratories, the principal contractor for the work, conducted a special exposure panel variability study.

The jective was to use replicate panel data to design an exposure panel program which would improve our ability to detect changes in the panel community composition and in the abundance of selected taxa.

Methods and results are detailed below.

Beginning in February, 1977, an extra rack with 12 replicate panels (wood and asbestos) was placed at Giants Neck (Figure 2E-1)

A similar rack was placed at Fox Island in August 1977.

The replicate panels were retrieved after six months exposure and replaced with additional replicates also retrieved after six months exposure.

Fauna on the wood and asbestos were enumerated separately.

Analyses applied to the data were directed toward evaluating panel variability. The number of taxa on the panels for each station / time series combination is shown in Table 2E-1.

The 7io 2-20

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LOCATIONS OF EXPOSURE PANEL STATIONS AROUND MILLSTONE POINT FIGURE 2E 1.

White Point, 2.

Fox Island, 3.

Effluent, 4.

Millstone Harbor, 5.

Intake, 6.

Giants Neck

(

J

TABLE 2E TOTAL NUMBER OF TAXA ON REPLICATE RACK PANELS FOR SERIES (FEB 77 - AUG 77), SERIES 2 (AUG 77 - FEB 78), oliD SERIES 3 (FEB 78 - AUG 78)

Panel No.

GN-1 GN-2 GN-3 FI-2 F1-3 1

14 8

13 10 10 2

15 10 10 8

9 3

11 9

11 10 9

4 12 7

11 10 10 5

11 7

10 9

10 6

12 6

9 9

9 7

8 9

10 8

8 8

10 6

13 9

8 9

9 7

10 8

9 10 12 7

13 10 9

11 10 9

11 8

10 12 11 9

9 8

9 Total 20 14 18 15 14 Mean 11.3 7.8 10.8 8.9 9.2 S.D.

1.96 1.34 1.47 0.90 0.72

mean number of taxa per panel ranged between 7.8 and 11.3.

Of all 39 taxa collected, only eight were found at every station time combination (Table 2E-2).

Species area curves were generated to determine the number of panels required to collect a given percent of the taxa.

Figures 2E-2 and 2E-3 show that six replicates were required at Giants Neck and Fox Island to collect over 85 percent of the total taxa.

The number of replicate panels required to detect specified differences between sample means was also estimated.

A plot of sample replication for given detection levels was generated following Sokal and Rohlf (1969) (Figure 2E-4).

Coefficients of variation (me.D' x 100) were calculated from panel data S

an based only upon the numbers or percent cover of those 'axa found at all stations during the replicability study (Table 2E-2).

For each of these dominant taxa the coefficient was approximately 60 percent. At this level, three replicates would only allow us to detect differences of about 100 percent witho< =.2 and

/3=.2.

About 15 replicates are needed to detect a 50 percent difference and over 50 replicates are required to detect differences of 25 percent (Figure 2E-4).

Is is apparent from these analyses that the exposure panel data are highly variable and that an inordinate number of replicates are required to make statistical inferences concerning changes in abundance of selected taxa.

^! l ')

0 J Jt-u 2-21

T,". hts 2E TAXA OCCURRENCE ON STATION / SERIES COMBINATIONS FOR REPLICATE RACKS Taxa found once:

Phyllodocc sp.

Terebellidae Capreila gecr:etrica Stylochus ellipticus Balanus balanoidcs Anomia sir: plex Crascostrca sp.

Crepidula plana Mytilus edulis llassa obsoleta Urocalpin: cinerea Electra cructulenta Schisoporeila unicornis Taxa found twice:

H: ichondria bowerbankia Bugula turrita Taxa found three times:

llcrcis sp.

Saballa microphthalma Serpulid (tubes)

Balanus crcnitus Balanus improvisus Littorina obtucata Botryllus schlossert Liwwria lignorum llcrats succinea Taxa found four times:

Hydroids Lepidonotus squ=atus Spirorbis sp. (tubes)

Crepidula fornicata Mitrclla lunata Bugula siq)le:

Bugula sp.

Taxa f ound every time and at every station:

Corophium insidiosum Balanus eburncus Balanus sp.

Crepidula sp.

Cryptocula pallasiana Lim;oria tripunctata l} h ~,l' L,.

1

'^

r Limnorla sp.

Tercdo navalis

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10 12 Number of Panels FIGURE 2E SPECIES AREA CURVE FOR REPLICATE RACY - GIANTS NECK

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10 20 30 40 50 70 100 Number of Samples NtPBFR OF SAMPLES NEEDED TO DETECT SPECIFIED DIFFERENCES AT cx=8=0.20 FIGURE 2E

SUMMARY

The MIT effort and the special variability study conducted by W. F. Clapp Laboratories each define the usefullness and the limitations of exposure panel data at Millstone Based on these findings it is the opinion of the Northeast Nuricar Energy Company that continuation of the Millstone exposure panel program would not change the conclusions reached to date concerning the impact of power plant. impacts on boring and fouling communities found on panels.

An untenable increase in effort would be equired to make statistica? inferences cor,cerning abundance of taxa.

Further, many years of preoperational and operational data exist which satisfactorily describe changes in species numbers and changes in the occurrence ot fouling organisms.

LITERATURE CITED natialle, 1979.

A monitoring program of the marine enviroement of tbe Millstone Point, Connecticut Area, Annual Report to Northeast Utilities Service Company, February, 1978.

Report No. 14892, Butt'lle - Columbus Laboratories, William F. Clapp Laboratories, Duxbuty, Massachusetts.

In:

Annual Report Ecol.cgical and liydrographic Studies, NUSCO, 1978 Battelle, 1978.

Ibid.

Report No. 14820.

Brc..n, R. T. and S. T. Moore, 1977.

An analysis of exposure panel data collected at Millstone Point, Connecticut.

Massachusetts Institute of Technology, Energy Laboratory Report No. MIT-El 77-015.

119 pp.

Hillrean, R. E. 1975.

Environmental monitoring through the use of exposure panels.

In:

Fisheries and Energy Production, ed. by S. B. Saila, Lexington Books, D.C. Heath and r apany, Lexington, Massachusetts pp. 55-76.

Hillman, R.

E.,

N. W. Davis and R. W. Cote.

1973.

A monitoring program on the Ecology of the marine envircnment of the Millstone Point, Connecticut Area, with special attention to key indicator organisms pre-operational phase.

Summary report to Northeast litilities Service Company, Battelle - Columbus Laboratories, William F. Clapp Laboratories, Duxbury, Massachusetts.

Sokal, R.

R.,

and F. J. Rohlf.

1969.

Biometry.

W. H., Freeman and Company, San Francisco, 247 pp.

3b/

[* b 2-22

4 F.

Thermal Plume Study, Section 4.6 The thermal plume study can be deleted from the ETS since all study requirements are satisfied. The survey was undertaken when Units 1 and 2 were in operation simultaneously.

Thermal infrared scanning, three-dimensional temperature measurement, dye release and tidal current measurement were included in the survey encompassing a complete tidal phase. A final report was submitted to the Director of Nuclear Reactor Regulation on April 15

'979.

352 05/

2-23

V,.

G.

Chlorination Study, Section 4.7 The chlorination study can be deleted from the EiS since all study requirements are satisfied.

The purpose of the study was to correlate levels of total residual chlorine at the quarry cut with levels of free available chlorine at the condenser outlets into the quarry. The study began in late 1975 and was completed in De.cember 1976.

The results of the study were reported in the Annual Environmental Operating Report, Part A: Nonradiological Report, dated March 31, 1977.

2cs a : ;,

'"0 2-24

Docket Nos. 50-245 50-336 ATTACHMENT 1 Millstone Nuclear Power Station, Unit Nos. 1 and 2 Proposed Revisions to Environmental Technical Specifications June, 1979 b

b'

3.1.2 Biota 3.1.2.1 Aquatic 3.1.2.1.1 Exposure Panels DELETED 5

0>>0 c

3.1-5

3.1.2.1.5 Benthic Survey Objective The objective is to examine in detail the populations cf benthic organisms in order to describe any plant effects.

Specification Benthic sand samples shall be collected quarterly at two intertidal sand stations, Jordan Cove and Giants Neck, and at four subtidal sand stations, Jordan Cove, Giants Neck, Effluent and Intake (Figure 3.1.1).

The size of the sampling device and the replication shall be sufficignt to cover a combined total surface area of at least 0.1 m at each sampling.

Samples shall be taken to a depth of at least Sem.

In the laboratory, samples shall be sieved through a.5mm mesh screen. Organisms retained on the screen shall be identified to the lowest practical taxon and enumerated.

Deviations from the above program are permitted when changes in habitat occur at a station and the data are no longer lg comparable.

In such instances a new station location will be found.

Reporting Requirement A non-routine report shall be submitted to NRC in accordance with Section 5.6.2a(2) when gross changes in population species composition or abundance are evident.

Such a change is one that is beyond normal seasonal fluctuation.

Otherwise reports shall be issued on a routine basis as described in Section 5.6.1.

Bases The basis for this program element is to provide direct observa-tion of the benthic conditions which exist in areas over which the plume passes as well as areas removed from the influence of the plume.

This will assist in identification of any benthic.mpacts which might be associated with station operation.

~

3.1-9 7f9 P!

JJL v

4 e

DELETED

,c n

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U # 1 3.1-10

3.1.2.1.7 Trawling Obj ectilve he objectives of this study are to provide information on the occurrence and distribution of the larger ground fish in the area.

Specification A 30-foot otter trawl with 1/4 inch cod-end liner shall be used to trawl six locations around Millstone Point every other week.

(Stations 2, 5, 6, 8, 11, 14 (Fig. 3.1-2).

Fish and 12 selected invertebrates collected shall be identified and representative numbers will be measured.

Efforts will be made to release uninjured individuals alive.

When subsampling is undertaken the following conditions shall apply:

1.

Subsampled data shall be of a comparable quality with Il previously collected data; 2.

Subsample data shall be comparable with similar data collected from the traveling screens during impingement samples; and 3.

Subsampled data shall be of a quality which will permit valid statistical analyses to be performed at a perfor-mance level comparable with previous analyses.

Deviations from the required sampling schedule may occur when, for example, it is not possible to trawl in an area either la because of ice or dense vegetation.

Reporting Requirement Reports shall be issued on a routine basis as described in Section 5.6.1.

Marked or gross changes, beyond seasonal variations, in species abunoance will be cause for the submit-11 tal of a non-routine report in accordance with Section 5.6.2.a.(2).

Disappearance of a previously common or abundant species (e.g.

flounder) shall also be the cause for submitting a non-routine report.

Bases The basis for this program element is that data on changes in overall species composition and abundances in the area are necessary for continucus monitoring of the plaat's operation and surveillance of its effects, if any, on the regional biota.

352 063 3.1-12

• O-'

r /

3.1.2.1.9 Entrainment Studies Objective The objective of the entrainment studies is to quantify the zooplankton (including fish eggs and larvae) that pass through the plants in order to assess the proportion of the zooplankton population subject to the entrainment stresses.

Specification Samples for zooplankton including fish eggs and larvae shall be collected at the plant discharges.

Sampling shall be done weekly and alternately at Units 1 and 2 so that each unit is sampled every other week.

From January through September, three samples shall be taken both day and night, three days per week.

From October through December three samples shall be taken both day and night on one day each week.

Deviations from this sampling schedule are permitted when all circulating water pumps are not operating at both units. The gg required number of weekly samples shall be obtained as long as the unit has at least one circulating pump operating.

Fish eggs and larvae shall be sorted and fish larvae shall be identified to the lowest practical taxonomic level in all samples.

On day and one night sample per week shall be proces-sed for the identification of all zooplankton.

Samples shall be collected using one meter diameter plankton nets with a 0.333 mm mesh size.

Alternate types of gear were evaluated for sampling the condenser cooling system in an attempt to determine the sampling method and location in the jg cooling system that would provide the most representative quantitative estimates of organisms entrained.

The method and location judged most suitable was then selected for the routin; samplings.

Reporting Requirement The number of fish eggs and larvae and other zooplankton entrained is directly related to the abundance in waters adjacent to the intake.

A prompt report shall be submitted in accordance with Section 5.6.2.a(2) when a species or zooplankton troup is entrained in numbers disproportionately large in relation to the local abundance.

Reporting requirements shall be more easily defined when verification of the mathematical models is finalized.

Otherwise data shall be reported on a routine basis as described in Section 5.6.1.

Bases Entrainment studies utilizing stationary plankton nets and other techniques at Millstoac Unit 1 intake, discharge and b2t 3.1-16

quarry cut have been conducted since initial operation of that plant in 1970.

To date the studies have provided detailed information on the entrainment stresses to both phytoplankton and zooplankton.

The ef fects of condenser pgsage on phyto-plankton prodictivity was determined using c assimilation.

Various mortality stresses were considered, i.e.,

temperature, chlorine, mechanical and combinations of each.

Mortality estimates were made for copepods and fish larvae.

Stratified sampling (3 depths) at the intake was used to determine vertical stratification of fish eggs and larvae entering Unit 1.

Comparisons were also made of the numbers caught at cach of the three sampling locations (intake, discharge and quarry cut).

The monitoring program as specificd above was selected based upon an analysis of these existing data.

Sampling variability at the intake and discharge were compared.

Since discharge samples showed less variation, these data were employed to determine the number of replicates and the frequency of sampling required to achieve estimates of population means within certain confidence limits at various precision levels.

Tripli-cate samples taken both day and night three days each week provide estimates with confidence limits of 33% at a 0.10 alpha level.

A lower level of effort is specified for the fall months:

October, November and December.

During this period the abundant or otherwise important ichthyoplankton species in terms of power plant impact assessment are found only in Jow abundance.

As a result, the parameters used to estimate the quantity of ichthyoplankton entrained (annual percent species composition and annual abundance) are little affected by a lower level of effort in the fall.

3.1-16(a)} {.j

3.1.2.1.10 Impingement Monitoring Objective Fish impingement shall be monitored to assure that impinge-ment losses remain at levels compatible with the local populations of fish and shellfish. Specification A minimum of three days each week, with no more than four days between counts, fish and shellfish washed from the traveling screens into the collection baskets over a 24-hour period shall be identified, counted, and the length recorded for a representative number of each species. ( Impingement records for Units Nos. 1 and 2 shall be combined monthly. The number of each species impinged per month shall be estimated by calculating the daily average of the cumulative total in any month and multiplying the daily average by the number of days in each month. Reporting Requirements The number of each species impinged shall be reported on a routine basis as described in Section 5.6. Data shall be reported by unit, species and length categories. The annual operating report shall include an analysis of the relationship between the estimated size of the species population (based on the relative abundance data collected according to specifications 3.1.2.1.3, 3.1.2.1.6 and 3.1.2.1.7) and the number impinged on the intake screens. g Bases Historical fish impingement levels at Millstone Unit No. 1 nave not been found to constitute a significant adverse impact based upon extensive studies of resident and migratory fish species. Using the numbers observed at Unit No. 1 predictions were made for Unit No. 2. The predictions were judged acceptable in terms of environmental impact. Initially, monthly report levels were established for each species size category impinged. The basis for including these report levels sas that the observed data could be used to establish a maximum level and that this maxi.am level would be the 5 highest monthly total that wauld normally be impinged at the plant. However, the two years of data on which these report levels were based were not adequate to define the year-to year variability of the many species collected on the screens, and the species size category report. levels did not account for one dominant size category growing into the next. Yearly comparisons will be made to determine the reiationships between species relative population size and the number impinged for the purpose of d termining the plar.t impact on the species popu'_eion in the site vicinity instead of the report l eve..s. 3.1-17 E 'l 1 3JL LUO

s- ~_ s s o e MANTIC 4,' IMY ~ s 4 6 5 ( k j L_ - g, > 2 ()) Giant's Neck intertidal: sand substrate (2) Giant's Neck subtidal: sand substrate (3) Effluent subtidal: sand substrate (20 feet MLU) (4) Jordan Cove intertidal: sand substrat3 (5) Jordan Cove subtidal: sand substrate (15 feet MLU) (6) Intake subtidal: sand substrate FIGURE 3.1-1 SAMPLING STATIONS FOR THE BENTHIC STUDIES 3.1-20

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4.6 Thermal Plume Study DELETED 352 Day 4.6-1

4.7 Chlorination Study 9 DELETED i d.7-1 ) b7d \\

ATTAO!MEili 2-ENERGY LABORATORY MASSACHUSETTS INSTITtlTE OF TECHNOLOGY t AN ANALYSIS OF EXPOSURE PANEL DATA COLLECTED AT MILLSTONE POINT, CONNECTICUT Russell T. Brown Stephen F. Moore Energy Laboratory July 1977 Report No. MIT-EL 77-015 d. N >=3g y /1 h -j n ) ~ t}}