§ 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 1 Chapter A7:

Entrainment Survival INTRODUCTION To calculate benefits associated with entrainment reduction, EPA used the assumption that all organisms passing through a facility's cooling water system would experience 100 percent mortality. This assumption was recommended in EPA's 1977 Guidance for Evaluating the Adverse Environmental Impact of Cooling Water Intake Structures on the Aquatic Environment: Section 316( b) P. L. 92 500. This is also the basic assumption currently used in the permitting programs for section 316( b) in Arizona, California, Hawaii, Louisiana, Maine, Maryland, Massachusetts, Minnesota, Nevada, New Hampshire, Ohio and Rhode Island ( Chen, 2002; Colarusso, 2002; Kimball, 2002; McCullough, 2002; McLean and Dieter, 2002; Stuber, 2002).

In comments on the Proposed Regulations to Establish Requirements for Cooling Water Intake Structures at Phase II Existing Facilities; Proposed Rule, a few of those commenting stated that this assumption may be incorrect and cited studies in which entrainment survival has been demonstrated. These entrainment survival studies were conducted by facilities to demonstrate that some organisms may survive the passage through the cooling water intake structure, and thus the assumption of 100 percent mortality may not be justified at their site.

EPA has obtained 36 entrainment survival studies conducted at 21 individual power producing facilities and conducted a detailed review. Twenty of these facilities are in scope for the section 316( b) Phase II rule for existing facilities. These facilities represent 3.7% of all section 316( b) Phase II existing facilities. EPA also reviewed a report prepared for the Electric Power Research Institute ( EPRI) ( EA Engineering Science & Technology, 2000) which summarized the results of 36 entrainment studies, 31 of which were the same studies reviewed by EPA. The intent of EPA's review was to determine the soundness of the findings behind the entrainment survival studies and to evaluate whether the assumption of 100 percent entrainment mortality is appropriate for use in the national benefits assessment for the section 316( b) Phase II rule to compare to the costs of installing the best available technology for minimizing adverse environmental impact.

A7 1 THE CAUSES OF ENTRAINMENT MORTALITY A7 1.1 Fragility of Entrained Organisms Cooling water intake structures entrain many species of fish, shellfish and macroinvertebrates. These species are most commonly entrained during their early life stages, as eggs, yolk sac larvae ( YSL), post yolk sac larvae ( PYSL) and juveniles, due to their small size and limited swimming ability. In addition to having limited or no mobility, these small life stages tend to be very fragile, and thus susceptible to injury and mortality from a wide range of factors ( Marcy, 1975). For these reasons, entrained eggs and larvae are believed to experience high mortality rates as a result of entrainment. The three primary factors contributing to the mortality of organisms entrained in cooling water systems are: thermal stress, mechanical stress, and chemical stress ( Marcy, 1975). The relative contribution of each of these factors to the rate of mortality of entrained organisms can vary substantially among facilities, based on the nature of their design and operations as well as the sensitivity of the species entrained ( Marcy, 1975, Beck et al., 1978, Ulanowicz and Kinsman, 1978). These three primary factors are discussed in more detail below. CHAPTER CONTENTS A7 1 The Causes of Entrainment Mortality . . . . . . . . . . A7 1 A7 2 Factors Affecting the Determination of Entrainment Survival . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A7 2 A7 3 Detailed Analysis of Entrainment Survival Studies Reviewed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A7 8 A7 4 Discussion of Review Criteria . . . . . . . . . . . . . . . A7 45 A7 5 Applicability of Entrainment Survival Studies to Other Facilities . . . . . . . . . . . . . . . . . . A7 49 A7 6 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . A7 49 § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 2 March 11, 2003 A7 1.2 Thermal stress Cooling water is used by facilities as a means of disposing of waste heat from facility operations. Thus, organisms present in the cooling water are exposed to rapid increases in temperatures above ambient conditions when passing through the cooling water system. This thermal shock can cause mortality or sub lethal effects which may affect further growth and development of entrained eggs and larvae ( Schubel et al., 1978; Stauffer, 1980). The magnitude of thermal stress experienced by organisms passing through a facility's cooling system depends on facility specific parameters such as intake temperature, maximum temperature, discharge temperature, duration of exposure to elevated temperatures through the facility and in the mixing zone of the discharge canal, the critical thermal maxima of the species, and delta T (  T, i. e., the difference between ambient water temperature and maximum water temperature within the cooling system) ( Marcy, 1975; Schubel et al., 1978). The extent of the effect of thermal stress can also vary among the species and life stages of entrained organisms ( Schubel et al., 1978; Stauffer, 1980).

A7 1.3 Mechanical stress Entrained organisms are also exposed to significant mechanical stress during passage through a cooling system which can also cause mortality. Types of mechanical stress include effects from turbulence, buffeting, velocity changes, pressure changes, and abrasion from contact with the interior surfaces of the cooling water intake structure ( Marcy, 1973, Marcy et al., 1978). The extent of the effect of mechanical stress can depend on the design of the facility's cooling water intake structure and the capacity utilization of operation. The amount of physical damage from mechanical stress can also vary among the species and life stages of entrained organisms ( Marcy, 1975; Marcy et al., 1978). Some studies have suggested that mechanical stress may be the dominant cause of entrainment mortality at many facilities ( Marcy, 1973, Marcy et al., 1978). For this reason, it has been suggested that the only effective method of minimizing adverse effects to entrained organisms is to reduce the intake of water ( Marcy, 1975).

A7 1.4 Chemical stress Chemical biocides are routinely used within cooling water intake structures to remove biofouling organisms. Chlorine is the active component of the most commonly used biocides ( Morgan and Carpenter, 1978; Morgan, 1980 ). These biocides are used in concentrations sufficient to kill organisms fouling the cooling system structures, and thus, may also cause mortality to the organisms entrained during biocide application. The extent of the effect of chemical stress can depend on the concentration of biocide and timing of its application. Eggs may be less susceptible to biocides than larvae ( Lauer et al., 1974; Morgan and Carpenter, 1978). Tolerance to biocides may also vary according to species. However, most species have been shown to be affected at low concentrations, < 0.5 ppm, of residual chlorine ( Morgan and Carpenter, 1978).

A7 2 FACTORS AFFECTING THE DETERMINATION OF ENTRAINMENT SURVIVAL There are many challenges that must be overcome in the design of a sampling program intended to accurately establish the magnitude of entrainment survival ( Lauer et al., 1974; Marcy, 1975; Coutant et al., 2001). Samples are almost certain not to be fully representative of the community of organisms ultimately experiencing entrainment. Some species are extremely fragile and disintegrate during collection or when preserved, and are thus not documented when samples are processed ( Boreman and Goodyear, 1981). This may be particularly true for the most fragile life stages, such as eggs and yolk sac larvae of many species. All sampling devices are selective for a certain size range of organisms, so that a number of sampling methods would have to be employed to accurately sample the broad size range of organisms subject to entrainment. The relative ability of different organisms to avoid sampling devices also determines abundance and species composition estimated from samples ( Boreman and Goodyear, 1981). This avoidance ability varies with the size, motility and condition of the organisms. If dead or dying organisms tend to settle out, then sampling will be selective for the live, healthy specimens ( Marcy, 1975). If, on the other hand, the healthy, more motile specimens are able to avoid sampling gear, the sampling will tend to be selective for dead or stunned specimens. The patchy distribution of many species ( Day et al., 1989; Valiela, 1995) creates difficulties in developing precise estimates of organism densities ( Boreman and Goodyear, 1981). The patchier the distribution, the greater number of samples required to reduce the uncertainty associated with the density estimates to an acceptable level.

The factors just discussed impact the ability to accurately establish the type and abundance of organisms present at the intake and discharge of a cooling water system. A second suite of factors, superimposed on the first, impacts the ability to estimate the percentage of those organisms that are alive and dead at those two locations. The greatest challenge to be overcome is posed by the fragility of the organisms being studied. The early life stages of most species are so fragile that § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 3 they may experience substantial mortality simply due to being sampled, both from contact with the sampling gear as well as in being handled for subsequent evaluation. For example, Marcy ( 1973) reported on the effects of current velocity on percent mortality of ichthyoplankton taken in plankton nets, and found he was able to constrain sampling mortality to 18 percent at velocities of 0.3 to 0.6 m/ sec. The loss or damage of organisms beyond identification during plant passage causes overestimations of the true fraction of live organisms in the discharge samples, because the disintegrated organisms are extruded from the sampling device ( Boreman and Goodyear, 1981).

The entrainment survival studies addressed in this review quantified survival by estimating the percent of organisms categorized as either alive, stunned or dead present in samples collected at the intake and discharge locations of a facility. In the studies reviewed, a variety of methods were used to determine the physiological state of sampled organisms, ranging from placing the sampled organisms in various types of holding containers for observation to the use of devices specifically designed for assessment of larval survival, such as a larval table. A variety of criteria were also used in these studies to categorize the physiological status of the organisms, such as opacity as an indicator of a dead egg, and movement of a larva in response to being touched as an indicator of being alive or stunned. The lack of standardized procedures applied for assessing physiological condition in all of the studies reviewed made comparisons of the study findings to each other difficult.

When quantifying entrainment survival, these studies used the estimates of the proportion dead from samples collected at the intake as controls to correct the samples at the discharge for mortality associated with natural causes, and sampling and handling stress. The use of intake samples as controls requires the assumption that sampling and handling induced mortality rates be the same at the intake and discharge, which, in turn, requires that sampling methods and conditions be nearly identical in both locations ( Marcy, 1973). This requirement is difficult to meet at most facilities because of the differences in the physical structures and hydrodynamic conditions that exist at intakes and discharges ( e. g., frequently high velocity, turbulent flow at discharges versus lower velocity, laminar flows at intakes). In many cases, the location and design of the cooling water intake and discharge structures may preclude use of the same type of sampling gear in both locations. Another assumption implicit in this approach is that mortality due to entrainment is entirely independent of mortality due to sampling and handling and that there be no interaction between these stresses, an assumption that is acknowledged but never proven true in the studies reviewed.

The percent alive in the intake control is frequently well below 100 percent because these fragile organisms experience substantial mortality from stresses caused by being collected. An additional factor contributing to the less than 100 percent alive in intake samples is that some dead organisms may be present in the water column being sampled, due to natural mortality or recirculation of water discharged from the cooling system. In many studies, the survival in the intake sample is extremely low, for example the intake survival for bay anchovy was zero percent in studies conducted at Bowline ( Ecological Analysts Inc., 1978), Brayton Point ( Lawler, Matusky & Skelly Engineers, 1999), and Indian Point ( Ecological Analysts Inc., 1978 and 1989). The studies reviewed corrected their discharge survival estimates to account for the control sample mortality by using the percent alive in the intake control samples in the following manner. First, the proportion initially alive at the intake ( PI) and discharge ( PD) samples was determined, for each species in most cases, using the following equation:

P or P = # of alive and stunned organisms Total number of organisms collected I D Using the intake proportion as the control, initial percent entrainment survival ( SI) was then calculated using the following equation:

S = P P 100 I D I

     × When latent mortality was studied, a sample of the alive and stunned organisms from the initial entrainment survival determination was observed for a given period of time. The latent survival rate calculated is the proportion of those which remained alive after a given period of time from only those which survived initially and not the total number sampled. The latent percent survival ( SL) was determine using the following equation: § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 4 March 11, 2003 S = 100 # of alive organisms after a given time from discharge samples # of organisms initially sampled alive or stunned indischarge samples # of alive organisms after a given time from intake samples # of organisms initially sampled alive or stunned in intake samples L ×

           Entrainment survival was then calculated by adjusting the initial entrainment survival with latent entrainment survival using the following equation:

Entrainment Survival (%) = S S I L × A variation of this formula, specifically Abbott's formula, is used for acute toxicity testing in the Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms ( EPA  821 R 02 012, 2002) and in testing of pesticides and toxic substances in Product Performance Test Guidelines OPPTS 810.3500 Premises Treatments ( EPA, 712 C 98 413), to adjust mortality for the possibility of natural deaths occurring during a test. This formula is intended to account for acceptable levels of unavoidable control mortality in the range of five to ten percent ( Newman, 1995). Abbott's formula is as follows:

Corrected mortality = 1  1  proportion dead in treatment 1  proportion dead in control

     This method of correcting for control mortality is often used in toxicological experiments in which organisms in concurrent control and experimental samples experience identical conditions except for the stressor that is the subject of study, and, as already noted, this method is applied when control mortalities, from stress due to holding or sampling and from natural causes, are generally low ( less than ten percent). In entrainment survival studies, sampling conditions at the intake and discharge are seldom identical. Also, the initial mortalities in the intake samples are often much higher than five or ten percent and sometimes higher than the mortality in the discharge samples.

In addition, the assumption that mortality due to entrainment is entirely independent of mortality due to sampling and handling with no interaction between these stresses may not, in fact, be true. The proportion of dead organisms observed in the intake samples is comprised of organisms that have died before sampling due to natural conditions, organisms that have died from the stress of sampling and sorting, and possibly organisms that have died from previous passages through the cooling water system at facilities where recirculation of water occurs. The proportion of dead organisms observed in the discharge samples is comprised of organisms that have died prior to passage through the facility from natural conditions, organisms that have died from the stresses associated with entrainment as described above, and organisms that have died due to the stress of sampling and sorting. The fundamental difference between the extent of the effect of sampling stress in the intake and the discharge samples is that the discharge samples are exposed to sampling stress after they have been exposed to entrainment stress. Thus the most vulnerable organisms may have already died due to entrainment and would not be alive at the time of sampling to die again from that stress. By correcting discharge samples for sampling and natural deaths using the intake results, the assumption is made that the mortality in the discharge sample is the result of the same probability of death due to sampling as in the intake sample and only the additional mortality is due to the stress of entrainment. When intake survival ( PI) is less than discharge survival ( PD), the use of the equation for entrainment survival ( SI) results in a calculation of 100 percent survival even though the majority of organisms may be dead in both samples ( EA Engineering Science & Technology, 2000). However, in the intake sample much of the mortality may be due to sampling stress whereas in the discharge sample much of the mortality may be due to entrainment stress. Additionally, the initial survival estimates may be overestimations of survival due to the disintegration of entrained organisms and their subsequent extrusion through the sampling gear ( Boreman and Goodyear, 1981). For all of the reasons described above, the applicability of this equation for determining entrainment survival by correcting discharge survival with intake survival is questionable. Also, the statistical attributes of these calculated mortality proportions are often not addressed. The higher and more variable the intake sample mortality percentages, the greater the degree of uncertainty that would be expected to be associated with the resultant entrainment survival estimates.

An additional factor that was not accounted for in all of the studies reviewed was the fate of organisms discharged into receiving waters after passage through the cooling system. Latent mortality studies were intended to document delayed mortality of organisms that were lethally injured or stressed during entrainment but were not killed immediately. Some studies ( e. g., Lauer et al, 1974) also reported that some fish larvae surviving entrainment behaved normally when § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 5 maintained in laboratory conditions for extended periods of time, eating and growing normally. However, larvae that did not experience immediate mortality or lethal stresses are discharged into receiving waters under conditions substantially altered from the normal environment in which present prior to entrainment, conditions very dissimilar to those experienced under laboratory conditions. Any naturally occurring vertical positioning of the organisms within the water column would be disrupted ( Day et al., 1989), and the turbulence and velocities present in discharge locations would be unlike the environmental conditions they experienced prior to entrainment. Under such altered conditions, their normal ability to feed or escape predation might be compromised. In addition, thermal shock can disrupt further development of eggs and larvae even if they survive entrainment ( Schubel et al., 1978). The potential for such phenomena to occur and the magnitude the effect may have on ultimate survival of entrained organisms would be nearly impossible to confirm or refute through field studies. However, were these phenomena to occur, they would result in mortalities beyond and in addition to the initial and latent mortalities that were the subject of the studies reviewed.

The factors discussed above served as the basis for EPA's review of the entrainment survival studies. Table A7 1 below presents summary information collected directly from each of the original studies reviewed: the facility where the study was conducted and whether more than one study was conducted at the same location, the month and year of sampling, the total number of samples and the number of days of sampling, the species for which entrainment survival was calculated, the total number of that species sampled during the entire study at the intake location, the total number of that species sampled during the entire study at the discharge location, whether the study determined initial or latent survival, the range of means of initial discharge survival for that species, and the range of means of latent discharge survival for that species ( which is out of the fraction of those which survived originally). In the last column, the value for entrainment survival presented is derived by multiplying the initial survival and the latent survival after correcting the discharge survival with the intake survival ( serving as a control).

Table A7 1: Summary of Entrainment Survival Study Results Facility Sampling Period Number of Samples and Days Species Number Sampled at Intake Number Sampled at Discharge Survival Study Initial Discharge Survival Latent Discharge Survival Survival Estimate Anclote September  November, 1985 120 samples 8 days Fish larvae Amphipods Chaetognatha Crab larvae Caridean shrimp 109 5185 1549 3007 2728 474 4662 1927 6145 1766 initial and 24 hour latent 8  47% 29  58% 28  35% 74  80% 45  66%      27  62% 49  73% 67  72% 21  100% 64  81%

Bergum Power Station April  June 1976 unknown # 6 days smelt perches unknown unknown 322 826 initial 10  28% 32  74%   10 41% 39 82%

Bowline Point June  July 1975 unknown # unknown days striped bass white perch bay anchovy 141 122 2134 111 168 1317 initial and 96 hour latent 74% 68% 2% 23% 26% 0% 70% 100% 22%

Bowline Point May  July 1976 unknown # 10 days striped bass PYSL white perch PYSL bay anchovy PYSL herrings PYSL Atlantic tomcod PYSL 118 54 148 46 54 207 42 1120 83 17 initial and 96 hour latent 54% 33% 0% 20% 29% 23% 21% 0% 1% 12% 26  77% 13  84%   0  80% 54%

Bowline Point March  July 1977 736 samples 46 days striped bass larvae white perch PYSL bay anchovy larvae herrings PYSL silverside PYSL 228 26 634 37 24 452 38 1524 22 56 initial and 96 hour latent 71  72% 34% 0  2% 23% 16% 55  66% 69% 0% 5% 0% 41  100% 16  62%   51%   Bowline Point March  October 1978 609 samples 40 days striped bass PYSL white perch PYSL bay anchovy PYSL herrings PYSL 646 190 325 271 792 301 763 51 initial and 96 hour latent 52  63% 19% 0  3% 23  63% 5  46% 0 5% 0% 0% 76  100% 52  68%     Bowline Point May  June 1979 435 samples 19 days striped bass PYSL white perch PYSL bay anchovy PYSL herrings PYSL 77 205 181 63 155 191 89 92 initial and 96 hour latent 35  41% 26  35% 0  4% 30  31% 8 20% 5 8% 0% 0 3% 24  42% 32%   0  58% § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival Table A7 1: Summary of Entrainment Survival Study Results Facility Sampling Period Number of Samples and Days Species Number Sampled at Intake Number Sampled at Discharge Survival Study Initial Discharge Survival Latent Discharge Survival Survival Estimate A7 6 March 11, 2003 Braidwood Nuclear June  July 1988 68 samples 3 days all species combined 191 103 initial 59%  100%

Brayton Point April  August 1997 February  July 1998 6829 samples 41 days winter flounder tautog windowpane flounder bay anchovy american sand lance 49 34 58 539 1091 965 401 58 15896 2941 initial and 96 hour latent 30  38% 4% 29  30% 0% 0%      90  100% 98  100% 65  67% 0% 100%

Cayuga Generating Plant May  June 1979 80 samples 24 days suckers carps and minnows perches 984 466 108 649 192 66 initial and 48 hour latent 75  92% 12  74 % 43  69% 93  98% 45  100% 44  61% 87  98% 25  86% 19  59%

Connecticut Yankee June  July 1970 102 samples 7 days alewife blueback herring unknown unknown initial 0 8%  0 25%

Connecticut Yankee June  July, 1971 and 1972 30 samples 2 days alewife blueback herring 273 795 initial 0  24%  0 26%

Contra Costa April  July, 1976 unknown # 7 days striped bass 637 329 initial 0  50%  0 95%

Danskammer Point Generating Station May  November 1975 372 samples 29 days striped bass PYSL white perch PYSL herrings PYSL 54 36 200 61 55 326 initial and 96 hour latent 39% 38% 20% 3% 4% 0% 95% 100% 80  87%

Fort Calhoun October 1973  June 1977 unknown # 89 days Ephemeroptera Hydropsychidae Chironomidae 2221 3690 2646 2220 4964 2925 initial 18  32% 47  56% 43  66%    92% 92% 84%

Ginna Generating Station June and August, 1980 255 samples 20 days alewife larvae rainbow smelt larvae 54 31 95 17 initial and 48 hour latent 0% 0%    0%

Indian Point June and July, 1977 unknown # 7 days striped bass PYSL white perch PYSL bay anchovy PYSL herrings PYSL 806 158 1254 100 518 67 704 65 initial and 96 hour latent 45  52% 15  43% 3  4% 10  11% 29  36% 15  30% 0% 0% 85  87% 73  89% 18  36% 40%

Indian Point May  July, 1978 unknown # 22 days striped bass PYSL white perch PYSL bay anchovy PYSL herrings PYSL 447 227 500 1046 1102 392 820 1104 initial and 96 hour latent 0  34% 0  37% 0% 0  8% 0 19% 6 15% 0% 0% 0  82% 0  58% 0% 0%

Indian Point Generating Station March  August 1979 unknown # 40 days Atlantic tomcod striped bass white perch herrings bay anchovy 266 127 195 254 457 212 153 147 186 485 initial and 96 hour latent 14  46% 62  77% 24  70% 28% 6% 15  75% 4  21% 18% 13% 4% 11  64% 59  75% 29  32% 22  31% 3  7%

Indian Point Generating Station April  July 1980 unknown # 44 days striped bass bay anchovy white perch 227 260 113 248 588 176 initial and 96 hour latent 50  81% 0  4% 0  90% 60 72% 0% 73% 55 81% 2 4% 50 90%

Indian Point Generating Station May  June 1985 unknown # 49 days bay anchovy PYSL 106 274 initial and 48 hour latent 6% 0% 0 24.3%

Indian Point Generating Station June 1988 unknown # 13 days striped bass larvae bay anchovy larvae 353 633 2710 7391 initial and 24 hour latent 62  68% 0  2% 24  44% 0% 60 79% 0 25% § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival Table A7 1: Summary of Entrainment Survival Study Results Facility Sampling Period Number of Samples and Days Species Number Sampled at Intake Number Sampled at Discharge Survival Study Initial Discharge Survival Latent Discharge Survival Survival Estimate March 11, 2003 A7 7 Indian River Power Plant July 1975  December 1976 46 samples 27 days bay anchovy Atlantic croaker spot Atlantic menhaden Atlantic silverside unknown unknown initial and 96 hour latent unknown unknown 0  100% 0  100% 25  100% 0  100% 0  100%

Muskingum River Plant 1979 no samples none specified 0 0 none intermediate to high potential    Northport Generating Station April and July, 1980 162 samples 20 days American sand lance winter flounder bay anchovy 29 13 7 782 17 11 initial and 48 hour latent 17% 35% 0% 2% 17% 0% 2% 10%   Oyster Creek Nuclear Generating Station February  August 1985 28 samples 20 days bay anchovy larvae winter flounder larvae 3396 3935 3474 2999 initial and 96 hour latent 0  71% 32  92% 0% 6  66% 0  68% 15  84%

Pittsburg Power Plant April  July, 1976 unknown # 7 days striped bass 196 266 initial 8  87%  12 94%

Port Jefferson April 1978 94 samples 5 days winter flounder sand lance fourbeard rockling American eel sculpin 36 249 216 107 22 26 191 144 96 17 initial and 96 hour latent 0  23% 12  40% 19  21% 94  96% 88% 50% 0  10%  71 96%  65% 25  86% 73  100% 100% 75%

PG& E Potrero January 1979 25 samples Pacific herring 546 716 initial and 96 hour latent 16%  70%

Quad Cities Nuclear Station June 1978 unknown # 5 days freshwater drum minnows 378 278 916 307 initial and 24 hour latent 0  71% 2  75%   2  62% 7  63%

Quad Cities Nuclear Station April  June 1984 unknown # 8 days freshwater drum carp buffalo unknown unknown unknown unknown unknown unknown initial and 24 hour latent unknown unknown unknown    63% 92  97% 94%

Roseton Generating Station May  November 1975 672 samples 41 days striped bass PYSL white perch PYSL herrings PYSL 100 77 471 172 97 833 initial and 96 hour latent 62% 29% 26% 6% 1% 0% 38%

Roseton Generating Station June  July 1976 unknown # 27 days striped bass PYSL white perch PYSL herring PYSL 93 401 1,054 80 349 645 initial and 96 hour latent 14  43% 6  42% 5  29%   0% 19  58% 11  79% 10  59%

Roseton Generating Station March May  July 1977 unknown # unknown days striped bass PYSL white perch PYSL herring PYSL Atlantic tomcod YSL 427 251 880 1178 765 266 1344 1345 initial and 96 hour latent 3  29% 0  17% 0  5% 16% 18% 27% 0% 40% 6  58% 0  52% 0 19% 41%

Roseton Generating Station March July  July 1978 256 samples 30 days striped bass PYSL white perch PYSL herring PYSL Atlantic tomcod PYSL 123 395 1274 83 211 459 1089 153 initial and 96 hour latent 27  50% 0  35% 0  10% 33  45% 18% 10% 0% 36% 46% 56 96% 0% 39%

Roseton Generating Station May  July 1980 1431 samples 42 days striped bass PYSL white perch PYSL herring PYSL 245 194 812 425 366 1252 initial and 48 hour latent 46  61% 30  59% 7  31% 48  56% 27  62% 1  3% 88% 67% 23% § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 8 March 11, 2003 A review of the data in table A7 1, above, shows that the majority of the studies were conducted at facilities located in a limited geographical region of the country, with 24 of the studies conducted in the northeastern region of the United States. This may explain why these studies provide entrainment survival estimates for relatively few, only 24, species or families of fish. The majority of survival estimates in these studies were for striped bass, white perch, bay anchovy, and herrings. Also, the majority of these studies are over 20 years old, with 25 of the studies conducted in the 1970' s. Thus, the results with regard to species composition and abundance may not be indicative of current conditions with improved water quality due to the enactment of the Clean Water Act in 1972. Entrainment survival in these studies was also estimated with relatively short sampling periods, with the 15 studies using sampling periods of approximately two months long. Also, the sampling periods did not always correspond to peak egg and larval abundance in the waterbody. Twelve of these studies determined that sample sizes of less than 100 individuals for a particular species at the discharge station were sufficient to give an accurate estimation of entrainment survival. These small sample sizes may not be sufficient to provide accurate estimates of entrainment survival given that these facilities entrain organisms on the order of millions to billions per year. Also, small sample sizes in conjunction with the high variability of entrainment survival increases the uncertainty associated with these estimations. The small sample sizes allowed for limited study of latent survival, and no facility attempted to study latent physiological effects of entrainment on a species such as the possible effect on growth rates, maturation, fertility, and vulnerability to natural mortality. The nature of the equation for entrainment survival results in estimates substantially higher than the proportion of survival in the discharge samples due to its use of a correction for mortality in the intake samples, which is often quite high. Although these studies indicate that entrainment survival may occur for certain species under certain conditions, the results may only be used to indicate the potential for survival, albeit most likely overestimated, for those species and life stages under those same conditions sampled at that particular facility. The fact that the existing studies are characterized by high uncertainty, high variability and the potential for high bias ( Boreman and Goodyear, 1981) complicates efforts to synthesize the various results in a manner that would provide useful generalizations of the results or application to other particular facilities. For these reasons, EPA believes that the reported results do not provide a clear indication as to the extent of entrainment survival significantly above zero percent to be used as a defensible assumption to calculate benefits for this rule.

A7 3 DETAILED ANALYSIS OF ENTRAINMENT SURVIVAL STUDIES REVIEWED The following pages provide detailed summary descriptions of each of the 36 studies reviewed. EPA reviewed these studies to determine if they were conducted in a manner that provides adequate representation of the current probability of entrainment survival at the facility. The criteria EPA used to evaluate the studies focused on three main themes: the sampling effort of the study, the operating conditions of the facility during the study, and the survival estimates determined as the result of the study. Specifically, EPA asked the following questions:

Sampling: When were samples collected? With what frequency were samples collected? Were samples collected when organisms were spawning, or at peak abundance? What time of day were samples collected? What was the number of replicates per sampling date? Were the intake and discharge samples collected at the same time so the results can be compared? How long was each sample collected? What method was used to collect samples? At what depth were samples collected? What was the location of the samples collected at the intake and discharge? Which water quality parameters were measured? Were dissolved organic carbon ( DOC) and particulate organic carbon ( POC) measured? What was the velocity at the intake and discharge?

Operating Conditions During Sampling: How many units at the facility were in operation? How many pumps at the facility were in operation? What was the intake temperature range, the discharge temperature range, and the   T range to which organisms were exposed? Were biocides in use?

Survival Estimation: How many sampling events occurred? What was the total number of samples collected? What was the total number of organisms collected? How many organisms are entrained each year at this facility? Did the study take into account fragmented organisms? Were the number of organisms collected at the intake and discharge comparable? What were the most abundant species collected? Were stunned larvae included with live larvae in survival estimates? Did the facility omit dead and opaque organisms from the count of dead organisms? How was latent survival studied? Were data sampled from all times and operating conditions combined to determine entrainment survival? What were the controls for the study? What was the range of intake survival determined by the study? What was the range of discharge survival determined by the study? How was entrainment survival calculated? Were confidence intervals or standard errors calculated? Were significant differences tested between intake and discharge survival? Was entrainment survival calculated for species with low sample sizes, such as less than 100 organisms? Was egg survival studied? Was there any trend evident in larval survival? Were the raw data provided to verify results? What was the trend of survival with regard § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 9 to temperature? What was the extent of mechanical mortality? What quality control procedures were used? Was the study peer reviewed? § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 10 March 11, 2003 Anclote Power Plant Anclote River, FL 1985 Study CCI Environmental Services, Inc., 1996 Sampling: Dates: Sept. 25  29, October 9  11, and November 1 2 Samples collection frequency: a few days per month Times of peak abundance: autumn months when densities maybe not the highest Time: mostly at night, some late afternoon to evening Number of replicates: varied between 5  25 per month Intake and discharge sampling: paired number, timing unknown Elapsed collection time: 20  30 minutes Method: 400 µ m mesh net with 1 m diameter and 5 gallon plastic bucket with 500 µ m mesh side panels Depth: mid depth and surface Intake location: unknown Discharge location: condenser discharge and point of discharge in canal Water quality parameters measured: pH, DO, salinity DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: operated at peak load to maximize   T, 1  2 Units Number of pumps in operation: varied due to sampling location, 0 4 pumps Temperature: Discharge temperature: 28.8  38.3

C   T average: 5.4  7.3

C Biocide use was not noted Survival Estimation: Number of sampling events: 8 Total number of samples collected: 120 Total number of organisms collected: 41,196 Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: approx. equal Most abundant species: not classified to species level Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars for 24 hours In several replicates, more organisms were counted after 24 hours in jar Data: was summarized and averaged over the entire sampling period Controls: survival in the intake samples was considered to be the control Initial intake survival range: 64% for Fish larvae 73% for Amphipoda 44% for Chaetognatha 72% for crab larvae 72% for Caridean shrimp Initial discharge survival range: 8  47% for Fish larvae 29  58% for Amphipoda 28  35% for Chaetognatha 74  80% for crab larvae 45  66% for Caridean shrimp Calculation of Entrainment Survival: Discharge survival / Intake survival Mean survival for each replicate was reported as survival estimate per species Confidence intervals ( 95%) and standard deviations were calculated Significant differences were tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: none collected Larval survival: decreased markedly within hours of collection Raw data: were provided to verify results Temperature effects: unknown Mechanical effects: unknown Quality control: QA/ QC officer oversaw sorting and sample handling Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 11 Bergum Power Station Bergumermeer,

Netherlands 1976 Study Hadderingh, 1978 Sampling: Dates: April 27  June 1 Samples collection frequency: approximately once per week Times of peak abundance: coincided with abundance of larvae and juveniles Time: unknown Number of replicates: unknown Intake and discharge sampling: unclear if paired sampling Elapsed collection time: 3 minutes Method: conical net with 0.5 mm mesh and 0.5 m diameter Depth: unknown Intake location: unknown Discharge location: in outlet before weir Water quality parameters measured: none DOC and POC measured: no Intake and discharge velocity: 40 cm/ sec Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: unknown Temperature: Intake temperature: 10.8  21.6 Discharge temperature: 16.7  24.6

C   T ranged from 2.4  8.0

C Biocide use was not noted Survival Estimation: Number of sampling events: 6 Total number of samples collected: unknown Total number of organisms collected: unknown at intake, 1148 at discharge Number of organisms entrained per year: unknown approximately 10 million organisms entrained per day in May Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: unknown Most abundant species: smelt, perches Stunned larvae: unknown if included in survival proportion Dead and opaque organisms: not discussed Latent survival: observed in floating buckets in the outlet canal for 24 hours 5  50% appeared to be dead in buckets floating in outlet canal However, latent survival was not explicitly studied Data: survival by sampling date and then averaged Controls: survival in the intake samples was considered to be the control Initial intake survival range: 54  100% for smelt 81  96% for perches Initial discharge survival range: 10  28% for smelt 32  74% for perches Calculation of Entrainment Survival: Discharge survival / Intake survival Confidence intervals and standard deviations were not presented. Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: no eggs collected Larval survival: increased in samples later in year, may be due to larger sized Raw data: were not provided to verify results Temperature effects: not discussed Mechanical effects: not discussed Quality control: not discussed Peer review: work done for facility, published in Applied Limnology § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 12 March 11, 2003 Bowline Point Generating Station Hudson River, NY 1975 Study Ecological Analysts Inc., 1976a Sampling: Dates: June 3  July date unknown Samples collection frequency: 1  4 times per week Times of peak abundance: sampling intended to coincide with peak densities Time: day or night Number of replicates: unknown Intake and discharge sampling: unknown if paired Elapsed collection time: 15 minutes Method: larval collection tables Depth: unknown Intake location: in front of intake Discharge location: from standpipe connected to discharge pipe of Unit 2 Water quality parameters measured: conductivity, DO, pH DOC and POC measured: no Intake and discharge velocity: intake: 1.5  2 m/ sec, discharge 2 4.6 m/ sec Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: unknown Temperature:   T range: 0.5  12.1

C Biocide use was not noted Survival Estimation: Number of sampling events: 37 Total number of samples collected: 400 Total number of organisms collected: 4643 Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: no, more at intake Higher percentage of larvae were collected at the discharge station in the later weeks of the collection period. Conversely, a higher percentage of larvae were collected at the intake at the beginning weeks of the collection period. This discrepancy in larval collection combined with higher survival rates later in the spawning season accounts for the bias which results in higher survival rates at the discharge station. The study acknowledges this bias and concludes that it is responsible for the higher discharge survival estimates Most abundant species: striped bass, white perch and bay anchovy Stunned larvae: included in initial survival proportion; most died within hours Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars for 96 hours Data: was summarized and averaged over the entire sampling period Controls: survival in the intake samples was considered to be the control Initial intake survival range: 81% for striped bass 56% for white perch 9% for bay anchovy Initial discharge survival range: 74% for striped bass 68% for white perch 2% for bay anchovy Calculation of Entrainment Survival: Discharge survival / Intake survival Confidence intervals ( 95%) were presented Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: no Egg survival: not studied Larval survival: decreased markedly within 3 hours of collection. Raw data: were not provided to verify results Temperature effects: too few samples collected to establish relationship Mechanical effects: extent was not discussed § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 13 Bowline Point Generating Station Hudson River, NY 1976 Study Ecological Analysts Inc., 1977 Sampling: Dates: May 18  July 26 Samples collection frequency: approx. 4 nights per week Times of peak abundance: for all species except Atlantic tomcod Time: at night Number of replicates: stated average of 10 per sampling trip Intake and discharge sampling: sorted simultaneously Elapsed collection time: 15 minutes Method: larval collection table with 4 inch diameter trash pump Depth: unknown Intake location: in front of Unit 1 trash racks Discharge location: from standpipes of discharge at Units 1 or 2 Water quality parameters measured: conductivity, pH, and DO DOC and POC measured: no Intake and discharge velocity: intake: 0.11  3 m/ sec, discharge: 3  4.6 m/ sec Operating Conditions During Sampling: Number of units in operation: varied between 1 and 2 Number of pumps in operation: unknown Temperature: discharge range: 29.0  35.9

C Biocide use was not noted Survival Estimation: Number of sampling events: 39 Total number of samples collected: 688 Total number of organisms collected: 2795 Number of organisms entrained per year: unknown Fragmented organisms: only included in count if > 50% was present Equal number of organisms collected at intake and discharge: no, very different Most abundant species: striped bass, white perch , atlantic tomcod, bay anchovy, herrings Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars for 96 hours Data: was summarized and averaged over the entire sampling period Controls: survival in the intake samples was considered to be the control Initial intake survival range: 81  90% for striped bass 62% for white perch 54  82% for Atlantic tomcod 7  53% for bay anchovy 35% for herrings Initial discharge survival range: 0  54% for striped bass 0  33% for white perch 29  94% for Atlantic tomcod 0  10% for bay anchovy 20% for herrings Calculation of Entrainment Survival: Discharge survival / intake survival Confidence intervals ( 95%) were presented Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: not studied Larval survival: decreased markedly within 12 hours of collection. Raw data: were not provided to verify results. Temperature effects: trend of decreasing survival when temperatures > 30

C Mechanical effects: unknown extent Quality control: color coded labels, immediate checks of sorted samples, SOPs Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 14 March 11, 2003 Bowline Point Generating Station Hudson River, NY 1977 Study Ecological Analysts Inc., 1978a Sampling: Dates: March 7  July 15 Samples collection frequency: 5 nights per week Times of peak abundance: covered of peak densities of most targeted species Time: at night Number of replicates: varied between 2 and 10 per site Intake and discharge sampling: paired Elapsed collection time: 15 minutes Method: larval table with pump, 2 pumps at intake; 2 tables at discharge ambient water injection system added to reduce prolonged temp. exposure Depth: middle to bottom at intake, at standpipes for discharge Intake location: in front of Unit 1 trash rack Discharge location from standpipes of either Unit 1 or 2, depending on operation Water quality parameters measured: conductivity, pH and DO DOC and POC measured: no Intake and discharge velocity: intake: 0.11 2 m/ sec; discharge 3  4.6 m/ sec Operating Conditions During Sampling: Number of units in operation: varied between 1 and 2 Number of pumps in operation: 2 pumps throttled or 2 pumps full Temperature: Intake range: 3.7  27

C   T range: not provided Biocide use was not noted Survival Estimation: Number of sampling events: 46 Total number of samples collected: 736 Total number of organisms collected: 4071 Number of organisms entrained per year: unknown Fragmented organisms: included in count if > 50% of organism was present Equal number of organisms collected at intake and discharge: no, very different Most abundant species: striped bass, white perch, bay anchovy, herrings and silversides Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars for 96 hours Data: was summarized and averaged over the entire sampling period Controls: survival in the intake samples was considered to be the control Initial intake survival range: 74% for striped bass 69% for white perch 0  16% for bay anchovy 54% for herrings 37% for silversides Initial discharge survival range: 71  72% for striped bass 34% for white perch 0  2% for bay anchovy 23% for herrings 16% for silversides Calculation of Entrainment Survival: Discharge survival / Intake survival Standard errors were presented Significant differences were tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: not studied Larval survival: survival increased with larval length Raw data: were not provided to verify results. Temperature effects: decreased survival > 33

C Mechanical effects: unknown § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 15 Bowline Point Generating Station Hudson River, NY 1978 Study Ecological Analysts Inc., 1979b Sampling: Dates: March 13  October 16 Samples collection frequency: 1  5 times per week Times of peak abundance: majority of samples in June and July Time: at night Number of replicates: varied between 1  10 per sampling date. Intake and discharge sampling: mostly paired, not all sites sampled all dates Elapsed collection time: 15 minutes Method: pump/ larval table combination; also floating larval table Depth: at bottom for intake and unspecified for discharge Intake location: in front of trash racks of Unit 1 or 2 Discharge location: at either Unit 1 or 2 in standpipes from discharge pipe floating larval table used for sampling at point of discharge Water quality parameters measured: salinity, pH, DO, conductivity DOC and POC measured: no Intake and discharge velocity: intake: 0.15  0.23 m/ s Operating Conditions During Sampling: Number of units in operation: varied between 1 and 2 Number of pumps in operation: unknown Temperature: unknown Biocide use was not noted Survival Estimation: Number of sampling events: 40 Total number of samples collected: 609 Total number of organisms collected: unknown Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: varied Most abundant species: striped bass, bay anchovy, white perch and herrings Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in holding jars for 96 hours Data: was summarized and averaged over the entire sampling period. Controls: survival in the intake samples was considered to be the control Initial intake survival range: 48  49% for striped bass 39% for white perch 4% for bay anchovy 19% for herrings Initial discharge survival range: 51  63% for striped bass 19% for white perch 0% for bay anchovy 23% for herrings Calculation of Entrainment Survival: Discharge survival / Intake survival Standard error were presented Significant differences were tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: not studied Larval survival: decreased markedly within 12 hours of collection Survival increased with larval length Raw data: were not provided to verify results Temperature effects: no survival for YSL for any species at temps. > 30

C no survival for PYSL for any species at temps. > 33

C majority of samples collected at temperatures < 30

C Mechanical effects: recirculation of water occurs Quality control: color coded labels, double checks, sorting efficiency checks Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 16 March 11, 2003 Bowline Point Generating Station Hudson River, NY 1979 Study Ecological Analysts Inc., 1981a Sampling: Dates: May 23  June 27 Samples collection frequency: 3  5 days per week Times of peak abundance: timed to coincide with peak densities Time: 1400 to 2200 hours Number of replicates: varied between 0  9 per sampling date, generally 7 Intake and discharge sampling: mostly paired, initiated simultaneously Elapsed collection time: 15 minutes Method: intake: floating larval table or rear draw sampling flume discharge: pumpless plankton sampling flume or pumped larval table Depth: intake: mid depth ( 4.6 m) discharge: 2 m below surface Intake location: in front of trash racks Discharge location: at standpipe and diffuser Water quality parameters measured: conductivity, pH, DO DOC and POC measured: no Intake and discharge velocity: intake: 1.5  3.0 m/ sec; discharge 3  4.6m/ sec Operating Conditions During Sampling: Number of units in operation: varied, power generated on only 5 sampling dates Number of pumps in operation: operated through sampling Temperature:   T range: not provided Biocide use was not noted Survival Estimation: Number of sampling events: 19 Total number of samples collected: 435 Total number of organisms collected: 1212 Number of organisms entrained per year: estimated 1.5 million striped bass 2.7 million white perch Fragmented organisms: included in count if 50% of organism was present Equal number of organisms collected at intake and discharge: approx. equal Most abundant species: white perch, bay anchovy, striped bass, herrings Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars for 96 hours. Data: was summarized and averaged over the entire sampling period. Controls: Survival in the intake samples was considered to be the control. Initial intake survival range: 63  71% for striped bass 39  63% for white perch 4  14% for bay anchovy 56  61% for herrings Initial discharge survival range: 35  41% for striped bass 26  35% for white perch 0  4% for bay anchovy 30  31% for herrings Calculation of Entrainment Survival: Discharge survival / Intake survival Standard errors were presented. Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: determined by translucency and hatching success Larval survival: decreased markedly within 12 hours of collection. Raw data: were not provided to verify results. Temperature effects: little survival at discharge temperatures > 30

C Mechanical effects: due to no power generation on the majority of sampling dates, results give indication of extent of mechanical induced mortality This study included analysis of diel patterns of ichthyoplankton abundance in comparison to diel patterns of plant generation. Facility tends to operate at 85 to 95 percent of capacity in the mid afternoon hours which results in higher   T's and discharge temperatures. Facility tends to operate at minimum level, 20 to 30 percent capacity, in early morning when larval abundance is high and entrainment survival samples collected. Sample collection during the hours when the facility is operating at minimum levels of percent capacity, and at times with correspondingly lower   T's and discharge temperatures, may add bias to the results since more organisms will be exposed to lower levels of temperature stress. The peak abundance for each species is only slightly higher than abundance throughout the day. Thus, collectively, more organisms may be exposed to higher temperatures and have higher mortality rates but are not reflected in samples collected at night. Quality control: color coded labels, check of sorting efficiency, SOPs Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 17 Braidwood Nuclear Station Kankakee River, IL 1988 Study EA Science and Technology, 1990 Sampling: Dates: June 1  July 5 Samples collection frequency: 3 samples taken in 35 days Times of peak abundance: peak densities of eggs and larvae were found in May Time: varied; day and night at intake, only day at discharge Number of replicates: varied, 8  14 per sampling date Intake and discharge sampling: more discharge replicates, not always same day Elapsed collection time: 2 minutes Method: plankton net with 1.0 m opening, net rinsed out in bucket Depth: unknown Intake location: in holding pond into which river water was pumped Discharge location: downstream of outfall in discharge canal Water quality parameters measured: none DOC and POC measured: no Intake and discharge velocity: 0.4  0.6 ft/ sec Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: unknown Temperature: not given Biocide use was not noted Survival Estimation: Number of sampling events: 3 Total number of samples collected: 62 Total number of organisms collected: 294 Samples, which were collected after peak densities, contained fewer and larger organism which may in turn have higher survival rates. Number of organisms entrained per year: estimate 5.8  11.2 million eggs/ larvae Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: more at intake Most abundant species: minnows and sunfish Stunned larvae: included in survival proportion Dead and opaque organisms: were omitted from all calculations of survival Thus 67% of those dead in the intake samples and 21% of those dead in the discharge samples were omitted from the survival proportions Latent survival: not studied Data: was summarized and averaged over the entire sampling period Controls: survival in the intake samples was considered to be the control. Initial intake survival range: 60% for minnows ( 17% including dead opaque) 78% for sunfish ( 54% including dead opaque) Initial discharge survival range: no minnows collected 80% for sunfish ( 76% including deadopaque Calculation of Entrainment Survival: Discharge survival / Intake survival Survival proportions calculated by dividing number of live larvae by number of live plus dead transparent larvae Confidence intervals / standard deviations: were not presented. Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: data not given Larval survival: not studied Raw data: were not provided to verify results. Temperature effects: not studied Mechanical effects: not studied Quality control: not discussed Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 18 March 11, 2003 .

Brayton Point Mount Hope Bay, MA 1997 1998 Study Lawler Matusky &

Skelly Engineers, 1999 Sampling: Dates: April 30  August 27, 1997 and February 26  July 29, 1998 Samples collection frequency: weekly Times of peak abundance: not discussed specifically Time: varied, day or night Number of replicates: varied between 14 and 77 Intake and discharge sampling: not paired, 2 tables located in discharge canal Elapsed collection time: 15 minutes Method: pump/ larval table combination Depth: mid depth for intake, 2  4 m below surface at discharge Intake location: directly in front of Unit 3 intake screens Discharge location: middle of discharge canal or from Unit 4 discharge pipe Water quality parameters measured: conductance and salinity periodically DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: unknown Temperature: intake range: 4.5  28.0

C discharge range: 11  45

C   T data not provided Biocide use: samples collected when not in use Survival Estimation: Number of sampling events: 41 Total number of samples collected: 2692 in 1997; 4137 in 1998 Total number of organisms collected: 2256 in intake; 27,574 in discharge Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal no. of organisms collected at intake and discharge: 4  79X more in discharge Most abundant species: bay anchovy, American sand lance Stunned larvae: assumed stunned larvae did not survive due to increased predation risk Dead and opaque organisms: not discussed Latent survival: observed in holding cups in aquarium racks for 96 hours Data: was summarized and averaged with both sampling years combined Controls: survival in the intake samples was considered to be the control Initial intake survival range: 0% for American sand lance 4% for tautog 0% for bay anchovy 44  46% for windowpane flounder 32% for winter flounder Initial discharge survival range: 0% for American sand lance 4% for tautog 0% for bay anchovy 29  30% for windowpane flounder 33  38% for winter flounder Calculation of Entrainment Survival: discharge survival / intake survival Standard errors were presented Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: not studied Larval survival: survival increased with larval length, decreased markedly within 4 hours of holding in latent studies Raw data: were provided by species and not by sample to verify results Temperature effects: survival decrease markedly at temps > 20

C Mechanical effects: unknown extent Quality control: continuous sampling plan which included reanalysis of samples Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 19 Cayuga Generating Plant Wabash River, IN 1979 Study Ecological Analysts Inc., 1980a Sampling: Dates: May 17  31 and June 8  22 Samples collection frequency: daily Times of peak abundance: highest average densities sampled were June 8  10 Time: 1900 to 0300 hours Number of replicates: varied between 0  6 per sampling date. Intake and discharge sampling: simultaneous sampling, transit time = 36 mins Elapsed collection time: 15 minutes Method: pump / larval table collection system Depth: intake: 2 and 5 m below surface, discharge: 3  4 m below surface Intake location: in front of intake structure Discharge location: where discharge of Units 1 and 2 enter canal also cooling tower discharge in discharge canal Water quality parameters measured: DO DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: varied, 2  4 Temperature: intake range: 17.6  24.3

C discharge range: 29.4  33.3

C   T ranged from 8.4  11.8

C Biocide use: occurs daily, but ceased at least 2 hours before sampling Survival Estimation: Number of sampling events: 24 Total number of samples collected: 80 Total number of organisms collected: 2556 Number of organisms entrained per year: unknown Fragmented organisms: 13  14.6% were damaged Equal number of organisms collected at intake and discharge: more at intake Most abundant species: suckers, perches, carps, temperate basses Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: 48 hour observation in aerated glass jars of filtered river water Data: was summarized and averaged over the entire sampling period Controls: survival in the intake samples was considered to be the control Initial intake survival range: 86  98% for suckers 28  92% for carps and minnows 50  86% for perches Initial discharge survival range: 75  92% for suckers 12  74% for carps and minnows 43  69% for perches Calculation of Entrainment Survival: Discharge survival/ Intake survival Confidence intervals: were not presented; standard errors were calculated standard error sometime as high as survival Significant differences were tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: not studied Larval survival: latent effects were not seen until 48 hours after collection Raw data: were provided to verify results Temperature effects: lower survival for all species at temperatures above 30 ° C Mechanical effects: survival decreased when number of pumps increased Quality control: sorting efficiency checks and color coded labels Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 20 March 11, 2003 Connecticut Yankee Atomic Power Company Connecticut River, CT 1970 Study Marcy, 1971 Sampling: Dates: June 30  July 29 Samples collection frequency: weekly Times of peak abundance: sampling dates were estimated times of peak larvae Time: varied throughout day to avoid biocide application Number of replicates: sampled in triplicate, data from replicates combined Intake and discharge sampling: samples taken successively not all sites sampled on all dates Elapsed collection time: 5 minutes Method: conical nylon plankton net with 1 L plastic bucket attached to cod end portable water table for maintaining temperature during counting Depth: median depth at intake; surface, middle and bottom of discharge because dead fish in canal may sink or float due to immobility or changes in specific gravity of water, thus giving inconsistent results Intake location: unknown Discharge location: outfall weir and 3 location in discharge canal Water quality parameters measured: DO DOC and POC measured: no Intake and discharge velocity: 1  2 ft/ sec, may approach 8 ft/ sec Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: unknown Temperature: Discharge temperature: 28.2  41

C   T ranged from 6  12.1

C Biocide use: sampling avoided daily application of 13% sodium hydrochlorite Survival Estimation: Number of sampling events: 7 Total number of samples collected: 102 Total number of organisms collected: 2681 Number of organisms entrained per year: unknown Fragmented organisms: majority of dead fish were mangled Equal number of organisms collected at intake and discharge: unknown Most abundant species: alewife and blueback herring Stunned larvae: not discussed Dead and opaque organisms: not discussed Latent survival: not studied Data: all data for all species combined, survival calculated for each date Controls: survival in the intake samples was considered to be the control Initial intake survival range: 29  100% for all species combined Initial discharge survival range: 0  7.5% for all species combined Calculation of Entrainment Survival: number live per cubic meter in each discharge sample/ number live per cubic meter in intake for each day Confidence intervals and standard deviations: were not presented Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: July 29 Egg survival: not sampled Larval survival: no organisms were found alive at end of discharge canal at temperatures > 30

C Raw data: were not provided to verify results Temperature effects: at discharge temp. > 33.5

C, no living organisms sampled Mechanical effects: not discussed Quality control: not discussed Peer review: published in notes of Journal Fisheries Research Board of Canada § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 21 Connecticut Yankee Atomic Power Company Connecticut River, CT 1971  1972 Study Marcy, 1973 Sampling: Dates: June 2  24, 1971 and June 27  July 13, 1972 ( mechanical only) Samples collection frequency: approximately once per week Times of peak abundance: unknown Time: afternoons and evenings Number of replicates: three at each station although at three different depths data were combined for each station Intake and discharge sampling: collected successively at the 5 sites Elapsed collection time: 5 minutes Method: conical nylon plankton net with 0.39 mm mesh and 1L plastic bucket Depth: surface, middle, and bottom Intake location: unknown Discharge location: below weir and 3 points along discharge canal Water quality parameters measured: none DOC and POC measured: no Intake and discharge velocity: 0.3  0.6 m/ sec, may approach 2.4 m/ sec Operating Conditions During Sampling: Number of units in operation: unknown in 1971, no power generation in 1972 Number of pumps in operation: unknown Temperature: Intake temperature: 16  26

C ( 1971); 19.9  28

C ( 1972) Discharge temperature: 29  35

C ( 1971 only)

  T ranged from 9 13

C ( 1971 only) Biocide use: 1972 study, chemical mortality indistinguishable from mechanical Survival Estimation: Number of sampling events: 2 ( 1971) and 7 ( 1972) Total number of samples collected: 30 ( 1971) and 246 ( 1972) often 2 3 times as many samples collected at discharge Total number of organisms collected: 1068 ( 1971) and 10,271 ( 1972) Number of organisms entrained per year: unknown, estimated entrainment is 1.7  5.8% of nonscreenable fish which pass facility Fragmented organisms: not discussed Equal no. of organisms collected at intake and discharge: 4X more in discharge lower numbers collected at end of canal may be due to dead fish settling out of water column Most abundant species: alewife and blueback herring Stunned larvae: were included as live unless they had begun to turn opaque Dead and opaque organisms: only opaque organisms were counted as dead Latent survival: not studied Data: replicate data combined; survival calculated per sampling day Controls: survival in the intake samples was considered to be the control Initial intake survival range: 64  100% for all species sampled ( 1971) Initial discharge survival range: 0% for all species sampled ( 1971) Calculation of Entrainment Survival: number live per cubic meter in each discharge sample/ number live per cubic meter in intake for each day Confidence intervals and standard deviations were not presented. Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: none sampled Larval survival: no survival anywhere in discharge at temperatures > 29

C Raw data: were not provided to verify results Temperature effects: organisms exposed to elevated temp. for 50  100 min estimated as causing 20% of mortality most fish are dead at the end of the 1.14 mile canal Mechanical effects: 1972 study indicated that 72  87% is mechanical mortality Quality control: not discussed § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 22 March 11, 2003 Contra Costa Power Plant San Joaquin River, CA 1976 Study Stevens and Finlayson,

1978 Sampling: Dates: April 28  July 10 Samples collection frequency: once per week Times of peak abundance: unknown Time: varied, about 25% of all samples collected at night Number of replicates: typically 3 Intake and discharge sampling: paired at closest time and temperature Elapsed collection time: 1  2 minutes Method: 505 micron mech conical nylon plankton net with 0.58 m plastic collecting tubes on cod end; towed net on boat at 0.6 ft/ sec Depth: mid depth Intake location: at intake for units 6 and 7 Discharge location: at discharge for units 1  5 and units 6 7 Water quality parameters measured: none DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: unknown Temperature: Intake temperature: 19  30

C Discharge temperature 19  38

C Biocide use was not noted Survival Estimation: Number of sampling events: 6 Total number of samples collected: unknown Total number of organisms collected: 966 ( 1606 at north shore control) Number of organisms entrained per year: unknown Fragmented organisms: enumerated in one replicate tow higher proportion of unidentifiable fragments in discharge Equal number of organisms collected at intake and discharge: more at intake Most abundant species: striped bass Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: not studied Data: was summarized by mean larval length Controls: survival in the intake samples was considered to be the control additional control on north shore to determine background mortality control site at north shore away from intake had lower mortality rates Initial intake survival range: 33 90% for striped bass recirculated water may be cause of some intake mortality Initial discharge survival range: 0  50% for striped bass Calculation of Entrainment Survival: paired discharge survival divided by paired intake survival Confidence intervals and standard deviations were not presented. Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: not studied Larval survival: increased survival with greater larval length Raw data: were not provided to verify results Temperature effects: mortality increased with increase in discharge temperature higher mortality with discharge temp. > 31 and   T > 7

C linear regression showed that half died at temps > 33.3

C 0% survival at temperatures of 38

C § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 23 Danskammer Point Generating Station Hudson River, NY 1975 Study Ecological Analysts,

Inc. 1976b Sampling: Dates: May 29  November 18 Samples collection frequency: varied from once every 2 weeks to 4 times per week Times of peak abundance: increased frequency during spawning Time: varied, generally overnight Number of replicates: varied, ranged from 1 to 12 Intake and discharge sampling: usually paired Elapsed collection time: unknown Method: pump/ larval table Depth: mid depth for intake, unspecified for discharge Intake location: in canal in front of traveling screens Discharge location: outlet of Unit 3 to Hudson River Water quality parameters measured: none DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: varied between 1 and 2 Temperature: Intake temperature range: 21  26

C Discharge temperature range: not provided   T ranged from 0  10

C Biocide use not used during sampling; noted that chlorination will reduce survival Survival Estimation: Number of sampling events: 29 Total number of samples collected: 372 Total number of organisms collected: 1655 Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal no. of organisms collected at intake / discharge: up to 2X more in discharge Most abundant species: herrings, striped bass and white perch Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars for 96 hours Data: was summarized and averaged over the entire sampling period Controls: survival in the intake samples was considered to be the control Initial intake survival range: 0  50% for striped bass 33  100% for white perch 63  100% for herrings Initial discharge survival range: 0  39% for striped bass 38  80% for white perch 20  22% for herrings Calculation of Entrainment Survival: Discharge survival / Intake survival Confidence intervals and standard deviations: were not presented. Significant differences were tested between the intake and discharge survival Significantly lower survival in discharge: herring PYSL Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: none collected Larval survival: decreased markedly within 3 hours of collection. Raw data: were not provided to verify results Temperature effects: significantly lower survival when   T > 10

C and discharge temperature > 30

C Mechanical effects: not discussed Quality control: samples double checked and data entry monitored Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 24 March 11, 2003 Fort Calhoun Nuclear Station Missouri River, NE 1973 1977 study Carter, 1978 Sampling: Dates: October 1973  June 1977 Samples collection frequency: 5  24 times per year Times of peak abundance: same frequency all year round Time: unknown Number of replicates: unknown Intake and discharge sampling: unknown if timing was paired Elapsed collection time: unknown Method: plankton net with 571 µ m mesh and 0.75 m diameter Depth: unknown Intake location: in river near intake Discharge location: near discharge in river immediately downstream of intake Water quality parameters measured: none DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: varied, 25 97% of full power or shut down Number of pumps in operation: unknown Temperature: Discharge temperature: 27.0  36.9

C during summer samples   T ranged from 0.6  13.5

C Biocide use: unspecified number of samples collected during chlorination Survival Estimation: Number of sampling events: 89 ( 16 when facility was shut down) Total number of samples collected: unknown Total number of organisms collected: 24,535 macroinvertebrates Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: no, varied Most abundant species: Ephemeroptera, Hydropsychidae, Chironomidae Stunned larvae: macroinvertebrates studied Dead and opaque organisms: not discussed Latent survival: not studied Data: was summarized and averaged over entire sampling period Controls: Survival in the intake samples was considered to be the control Initial intake survival range: 12  26% for Ephemeroptera 42  51% for Hydropsychidae 35  60% for Chironomidae Initial discharge survival range: 18  32% for Ephemeroptera 47  56% for Hydropsychidae 43  66% for Chironomidae Calculation of Entrainment Survival: Average differential mortality Confidence intervals / standard deviations: were calculated but not presented Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: not collected Larval survival: macroinvertebrates only were studied Raw data: were not provided to verify results Temperature effects: discussed but data not presented Mechanical effects: studied during 16 dates when facility was shut down Quality control: unknown Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 25 Ginna Generating Station Lake Ontario, NY 1980 Study Ecological Analysts Inc., 1981b Sampling: Dates: June 11  24 and August 8  21 Samples collection frequency: 5 times per week Times of peak abundance: to coincide with peak densities of targeted species Time: late afternoon or early evening Number of replicates: unknown Intake and discharge sampling: simultaneous sampling at both sites Elapsed collection time: 15 minutes Method: Intake: pump to floating rear draw sampling flume Discharge: floating rear draw pumpless plankton sampling flume Also used ambient water injection to reduce exposure to high temps. Depth: unknown Intake location: at screenhouse intake after flow through 3,100 ft intake tunnel Discharge location: discharge canal Water quality parameters measured: none DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: unknown Temperature: Discharge range: 18.5  34.4

C   T ranged from 8  10

C Biocide use: sampled 4 hours after routine injections Survival Estimation: Number of sampling events: 20 Total number of samples collected: 255 Total number of organisms collected: 664 Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: varied Most abundant species: alewife Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars of filtered water for 48 hours Data: was summarized and averaged over the sampling month Controls: survival in the intake samples was considered to be the control Initial intake survival range: 16.3% for alewife eggs 39% for alewife larvae 58 71% for rainbow smelt Initial discharge survival range: 62.5% for alewife eggs; 16% hatching success 0% for Alewife larvae 0% for rainbow smelt Calculation of Entrainment Survival: Discharge survival/ Intake survival In June, only one larvae was found alive int the discharge samples Standard errors were presented Significant differences were tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Too few of many species were collected at the two sites ( only 1 or 2 per site) to provide any reliable estimate of entrainment survival Egg survival: determined by translucency and hatching success Raw data: were provided to verify results Temperature effects: none survived at any temperature Mechanical effects: none survived at any temperature Quality control: SOPs, color coded labels, sorting efficiency checks Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 26 March 11, 2003 Indian Point Generating Station Hudson River, NY 1977 Study Ecological Analysts Inc., 1978c Sampling: Dates: Jun 1  July 15 Samples collection frequency: twice per week Times of peak abundance: expected to coincide with peak densities Time: 1800  0200 hours Number of replicates: varied between 5  7 per sampling date. Intake and discharge sampling: Elapsed collection time: 15 minutes Method: pump/ larval table with ambient water injection to reduce temp. stress Depth: unknown Intake location: at intake of Units 2 and 3 Discharge location: discharge for Unit 3 and discharge common to all Units Water quality parameters measured: DO, pH and conductivity DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: varied between 2 and 3, outage at Unit 2 from 7/ 4 Number of pumps in operation: 6, at or near full capacity Temperature: Intake range: 18.8  26.4

C Discharge range: 22.7  34.9

C   T during study not provided Biocide use: unknown Survival Estimation: Number of sampling events: 7 Total number of samples collected: unknown Total number of organisms collected: 4097 Number of organisms entrained per year: unknown Fragmented organisms: not discussed specifically, however, there were 115 Morone spp. organisms which could not be further identified to the species level and there were 55 organisms which were mutilated to the point of being unidentifiable to even the family level of organization. Entrainment survival may have been even lower if these mutilated samples were included in the assessment. Equal number of organisms collected at intake and discharge: more at intake Most abundant species: striped bass, white perch, bay anchovy and herrings Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: in aerated holding container in ambient water bath for 96 hours Data: was summarized and averaged over the entire sampling period Controls: survival in the intake samples was considered to be the control Initial intake survival range: 0  11% for bay anchovy 60  77% striped bass 66% for white perch 36% for herrings Initial discharge survival range: 3% for bay anchovy 29  45% for striped bass 15% for white perch 11% for herrings Calculation of Entrainment Survival: Discharge survival / Intake survival Standard errors were presented Significant differences were tested between the intake and discharge survival Significantly lower survival in discharge: striped bass YSL and PYSL white perch PYSL bay anchovy PYSL herring PYSL Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: not studied Raw data: were not provided to verify results Temperature effects: no determination that temperature had a significant effect Mechanical effects: unknown Quality control: color coded labels and immediate checks of sorted samples Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 27 Indian Point Generating Station Hudson River, NY 1978 Study Ecological Analysts Inc., 1979c Sampling: Dates: May 1  July 12 Samples collection frequency: 2 consecutive days per week Times of peak abundance: coincided with spawning of targeted species Time: 1800  0200 hours Number of replicates: approximately 6 per date Intake and discharge sampling: simultaneous Elapsed collection time: 15 minutes Method: pump/ larval table with ambient water injection Depth: 1  3 m below surface, approximately mid depth Intake location: Unit 2 and 3 intake Discharge location: Unit 2 and 3 discharge, discharge point common to all units Water quality parameters measured: conductivity, pH and DO DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: varied between 1 and 2 Number of pumps in operation: varied between 5  11, near full capacity Temperature: Intake range: 11.2  24.3

C Discharge range: 19  36

C   T ranged from 9  12

C Biocide use was not noted Survival Estimation: Number of sampling events: 22 Total number of samples collected: unknown Total number of organisms collected: 4496 Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: more at discharge Most abundant species: striped bass, white perch, bay anchovy and herrings Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars for 96 hours Data: was summarized and averaged over the entire sampling period Controls: survival in the intake samples was considered to be the control Initial intake survival range: 26  48% for striped bass 15  48% for white perch 18% for herring 2% for bay anchovy Initial discharge survival range: 0  34% for striped bass 0  37% for white perch 0  8% for herring 0% for bay anchovy Calculation of Entrainment Survival: Discharge survival/ Intake survival Standard errors were presented Significant differences were tested between the intake and discharge survival Significantly lower survival at discharge: striped bass YSL, PYSL and juveniles white perch PYSL herring PYSL Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: none were alive in either the intake or discharge samples Larval survival: decreased markedly within 24 hours of collection. Raw data: were not provided to verify results Temperature effects: at temps. > 30

C, no striped bass or white perch survived also 0% survived when both Unit 2 and 3 were running § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 28 March 11, 2003 Indian Point Generating Station Hudson River, NY 1979 Study Ecological Analysts Inc., 1981c Sampling: Dates: March 12  22 and April 30  August 14 Samples collection frequency: March: 4 times per week, rest was 2 consecutive days per week Times of peak abundance: coincided with spawning of targeted species Time: 1700 to 0200 Number of replicates: unknown Intake and discharge sampling: simultaneous sampling Elapsed collection time: 15 minutes Method: March sampling: two pump/ larval table combination April August sampling: rear draw plankton sampling flume at intake pumpless plankton sampling flume at discharge Depth: mid depth for intake, 1  5 m below surface for discharge Intake location: of Units 2 and 3 Discharge location: in discharge canal for Unit 3 and at end of canal Water quality parameters measured: conductivity, pH and DO DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: one unit not operating March 20  26 only one continuously April  August Number of pumps in operation: varied between 5 and 12 Temperature: Discharge range: 12.0  21.9

C in March; 24  32.9

C   T data not provided Biocide use was not noted Survival Estimation: Number of sampling events: 8 in March; 32 in April  August Total number of samples collected: unknown Total number of organisms collected: 478 in March; 2362 April August Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: varied Most abundant species: Atlantic tomcod, striped bass, white perch, herring, bay anchovy Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars with filtered water for 96 hours Data: sorted by discharge temperature in March; combined all April  August Controls: survival in the intake samples was considered to be the control Initial intake survival range: 43  68% for Atlantic tomcod 39  56% for striped bass 13  33% for white perch 23% for herrings 10% for bay anchovy Initial discharge survival range: 14  46% for Atlantic tomcod 62  77% for striped bass 24  70% for white perch 28% for herrings 6% for bay anchovies Calculation of Entrainment Survival: For the fish larvae samples, a difference in stress associated with the different sampling techniques at the intake and discharge was given as the reason why discharge survival was higher than intake survival for each taxa sampled. Thus, entrainment survival was not calculated. Standard errors were presented Significant differences were tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: determined by translucency and hatching success; 33% hatched in discharge samples; 44% in intake samples Larval survival: decreased markedly within 3 hours of collection. Raw data: were not provided to verify results. Temperature effects: no white perch or striped bass survival at temps. > 33

C Mechanical effects: unknown extent Quality control: sorting efficiency checks, color coded labels and SOPs Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 29 Indian Point Generating Station Hudson River, NY 1980 Study Ecological Analysts Inc., 1982 Sampling: Dates: April 30  July 10 Samples collection frequency: 4 consecutive nights per week Times of peak abundance: coincided with primary spawning of target species Time: 1600  0200 hours Number of replicates: unknown Intake and discharge sampling: initiated simultaneously Elapsed collection time: 15 minutes Method: intake: rear draw plankton sampling flume mounted on raft discharge: pumpless plankton sampling flume mounted on raft Depth: unknown Intake location: Unit 3 intake Discharge location: discharge port number 1 Water quality parameters measured: conductivity, DO, pH DOC and POC measured: no Intake and discharge velocity: intake: 0.3 m/ sec; discharge 3 m/ sec Operating Conditions During Sampling: Number of units in operation: varied between 1 and 2, Unit 2 offline June 4 11 Number of pumps in operation: varied between 5 and 11 Temperature: intake range: 11.3  25.1

C discharge range: 23  31

C   T data not presented Biocide use was not noted Survival Estimation: Number of sampling events: 44 Total number of samples collected: unknown Total number of organisms collected: 2355 Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: more at discharge Most abundant species: striped bass, white perch, bay anchovies Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars for 96 hours Data: combined by discharge temperature Controls: survival in the intake samples was considered to be the control Initial intake survival range: 95% for striped bass 93% for white perch 32% for bay anchovies 40% recirculation can occur so intake mortality may include organisms which were dead due to a previous passage through the facility Initial discharge survival range: 50 81% for striped bass 0 90% for white perch 0 4% for bay anchovy Calculation of Entrainment Survival: Discharge survival / intake survival Confidence intervals / standard deviations: were not presented. Significant differences were tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: hatching success: 82% in intake, 47% in discharge Larval survival: decreased markedly within 3 hours of collection. Raw data: were not provided to verify results Temperature effects: little survival at discharge temps > 33

C Mechanical effects: unknown Quality control: sorting efficiency checks, color coded labels and SOPs Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 30 March 11, 2003 Indian Point Generating Station Hudson River, NY 1985 Study EA Science and Technology, 1986 Sampling: Dates: May 27  June 29 Samples collection frequency: daily Times of peak abundance: sampling did not occur during time of peak densities Time: daytime, switched to nighttime after June 11 due to low sample sizes Number of replicates: unknown Intake and discharge sampling: simultaneous sampling Elapsed collection time: 13  15 minutes ( 200 m3) Method: barrel sampler with 2 coaxial cylinders with 505 µ m mesh one sampler at intake; 2 at discharge Depth: unknown Intake location: in front of Unit 2 intake Discharge location: in discharge canal downstream from Unit 2 discharge Water quality parameters measured: salinity, DO, pH and conductivity DOC and POC measured: no Intake and discharge velocity: discharge: 2.8  10 ft/ sec Operating Conditions During Sampling: Number of units in operation: varied between 1 and 2 Number of pumps in operation: unknown Temperature: Intake range: 20.3  22.9

C Discharge range: 26.6  30.3

C   T range: 4.6  8.5

C Biocide use: residual chlorine not measured Survival Estimation: Number of sampling events: 49 Total number of samples collected: unknown Total number of organisms collected: 457 Cited low efficiency of sampling gear as part of reason for low numbers of organisms sampled Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal no. of organisms collected at intake and discharge: 3X more at discharge Most abundant species: bay anchovy Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars for 48 hours Data: was summarized and averaged over the entire sampling period Controls: survival in the intake samples was considered to be the control Initial intake survival range: 23% for bay anchovy Initial discharge survival range: 6% for bay anchovy Calculation of Entrainment Survival: Discharge survival / Intake survival Confidence intervals ( 95%) were presented No calculations of significance due to small sample size Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: none collected Larval survival: decreased markedly within 3 hours of collection. Raw data: were not provided to verify results Temperature effects: unknown, too narrow of temperature range sampled Mechanical effects: New dual speed pumps installed in Unit 2 in 1984, study was conducted to determine whether extent of mechanical mortality differed from previous studies. Quality control: SOPs, reanalysis of samples, double keypunch of all data Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 31 Indian Point Generating Station Hudson River, NY 1988 Study EA Engineering Science and Technology, 1989 Sampling: Dates: June 8  June 30 Samples collection frequency: unclear Times of peak abundance: sampling not at peak densities for targeted species Time: afternoon and evening hours Number of replicates: varied, unknown number per day Intake and discharge sampling: simultaneous with twice as many at discharge Elapsed collection time: 15 minutes Method: rear draw sampling flumes, 1 at intake and 2 at discharge Depth: unknown at intake, surface at bottom at discharge Intake location: on raft in front of Intake 35 Discharge location: downstream from flow of Units 2 and 3 Water quality parameters measured: salinity, DO, pH DOC and POC measured: no Intake and discharge velocity: discharge 2.2  10.0 ft/ sec Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: unknown Temperature: Intake range: 20.3  23.8

C   T range: not provided Biocide use: residual chlorine not monitored Survival Estimation: Number of sampling events: 13 Total number of samples collected: unknown Total number of organisms collected: 12,333 Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: 10X more in discharge Most abundant species: bay anchovy, striped bass, white perch Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars for 24 hours Data: was summarized and averaged over the entire sampling period; discharge survival estimates include data from direct release studies and combined surface and bottom samples Controls: survival in the intake samples was considered to be the control Initial intake survival range: 0  8% for bay anchovy 86  90% for striped bass Initial discharge survival range: 0  2% for bay anchovy 62  68% for striped bass Calculation of Entrainment Survival: discharge survival / intake survival Standard errors were presented Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: none survived in intake and discharge samples Larval survival: decreased markedly within hours of collection Raw data: were not provided to verify results Temperature effects: undetermined effect; too narrow range tested Mechanical effects: study was conducted to determine the effect of the installation of dual speed circulating water pumps in Unit 2 in 1984 and variable speed pumps in Unit 3 in 1985; mechanical effects were determined to be main cause of mortality when discharge temperatures are < 32

C Quality control: SOPs, sampling stress evaluation, reanalysis of samples, double keypunch data Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 32 March 11, 2003 Indian River Power Plant Indian River Estuary 1975  1976 Study Ecological Analysts Inc., 1978b Sampling: Dates: July 2, 1975  December 13, 1976 Samples collection frequency: once or twice monthly Times of peak abundance: samples not taken frequently enough to detect Time: mostly at night Number of replicates: varied Intake and discharge sampling: not paired discharge samples not always collected Elapsed collection time: approximately 5 minutes or until sufficient # collected Method: 0.5 m diameter plankton sled with 505 µ m net rinsed in 10L of water of unspecified origin Depth: unknown Intake location: from foot bridge over intake canal Discharge location: in discharge canal under roadway bridge Water quality parameters measured: unknown DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: unknown Temperature: Intake range:  0.2  29.2 Discharge range: 5.4  39

C   T ranged from 5.2  9.0

C Biocide use was not noted Survival Estimation: Number of sampling events: 27 Total number of samples collected: 25 intake and 21 discharge Total number of organisms collected: unknown Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: unknown Most abundant species: bay anchovy, Atlantic croaker, spot, weakfish, Atlantic menhaden and Atlantic silversides Stunned larvae: not discussed Dead and opaque organisms: not discussed Latent survival: in holding containers in ambient water baths for 96 hours Data: sorted based on discharge temperature Controls: survival in the intake samples was considered to be the control. Initial intake survival range: not provided Initial discharge survival range: not provided Calculation of Entrainment Survival: not all were counted for most abundant species, a random sample was used instead Confidence intervals / standard deviations: were not presented. Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms: unknown Egg survival: were alive in either the intake or discharge samples. Larval survival: unclear trend Raw data: in Appendix B not available to EPA Temperature effects: all species had lower survival at discharge temps > 20 ° C. only Spot survived above 35

C though linear regression Mechanical effects: unknown, however dye studies performed at this facility and recirculation of discharge water has been shown to occur. The extent to which organisms are entrained repeatedly and the effect this has on the number of organisms that were shown to have died through natural causes or from sampling is not known. Thus some intake mortality may be due to the organism's previous passage through the facility. Quality control: unknown Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 33 Muskingum River Plant Muskingum River, OH Literature Review Ecological Analysts Inc., 1979a Sampling: no on site sampling conducted Operating Conditions During Sampling: no sampling conducted Survival Estimation: analyzed pressure regimes in circulating water system measured discharge temperature and   T at the facility determined that pressure regimes were similar to facilities with entrainment survival studies determined that low survival occurs at   T > 7.8

C which occurs for a small portion of entrainment season reviewed documentation of survival at other steam electric stations concluded that potential of survival at this facility was intermediate to high Peer review: literature review prepared for facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 34 March 11, 2003 Northport Generating Station Long Island Sound, NY 1980 Study Ecological Analysts Inc., 1981b Sampling: Dates: April 10  22 and July 10  23 Samples collection frequency: 5 nights per week Times of peak abundance: attempted to coincide with peak abundance Time: 1700  0100 hours Number of replicates: unknown Intake and discharge sampling: simultaneous Elapsed collection time: 15 minutes Method: floating rear draw sampling flume with 505 µ m mesh screens with ambient water injection system Depth: intake: 2 8 m below surface; discharge: 1.5 m Intake location: immediately in front of Unit 2 or 3 trash racks Discharge location: immediately in front of Unit 2 or 3 seal well Water quality parameters measured: DO, pH, conductivity DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: unknown Temperature: Discharge range: 15.9  35

C, ave 19.9 in April and 33.6 in July   T ranged from 8.6  15.0

C Biocide use was not noted Survival Estimation: Number of sampling events: 20 Total number of samples collected: 162 Total number of organisms collected: 884 in April and 76 in July Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: more at discharge Most abundant species: American sand lance, winter flounder, northern pipefish Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in aerated jars of filtered ambient water for 48 hours Data: was summarized and averaged over the entire sampling period Controls: survival in the intake samples was considered to be the control Initial intake survival range: 66% for American sand lance 85% for winter flounder 28% for bay anchovy Initial discharge survival range: 17% for American sand lance 35% for winter flounder 0% for bay anchovy Calculation of Entrainment Survival: discharge survival / intake survival Stated that survival estimate based on 4 assumptions: that the survival at the discharge is the product of the probabilities of surviving entrainment and sampling, that the survival at the intake is the probability of surviving sampling, that at the discharge there is no interaction between the two stresses, and each life stage consists of a homogenous population in which all individuals have the same probability of surviving to the next life stage Standard errors were presented Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: none collected Larval survival: decreased markedly within 6 hours of collection. American sand lance significantly larger in intake sample Raw data: were provided to verify results § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 35 Oyster Creek Nuclear Generating Station Barnegat Bay, NJ 1985 Study EA Engineering Science and Technology., 1986 Sampling: Dates: February  August Samples collection frequency: unknown Times of peak abundance: smaller samples collected during peak densities Time: unknown Number of replicates: unknown Intake and discharge sampling: discharge collected 2 minutes after intake Elapsed collection time: approximately 10 minutes Method: barrel sampler with 2 nested cylindrical tanks with 331 mm mesh Depth: unknown Intake location: northernmost intake groin west of recirculation tunnel Discharge location: easternmost condenser discharge point Water quality parameters measured: DO, salinity and pH in latent studies DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: unknown Temperature: Discharge range: 13.5  39.3

C   T ranged from  0.2  12.1

C Biocide use: chlorine concentration was measured, but not detected Survival Estimation: Number of sampling events: 20 Total number of samples collected: 13 for bay anchovy eggs, 10 for bay anchovy larvae and 5 for winter flounder Total number of organisms collected: 60,274 Number of organisms entrained per year: 619 million to 15.4 billion Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: no Most abundant species: bay anchovy and winter flounder Stunned larvae: included in initial survival proportion; as well as damaged Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars in water baths for 96 hours Data: grouped by 3 day long sampling events Controls: survival in the intake samples was considered to be the control Initial intake survival range: 38  91% for bay anchovy larvae 77  96% for winter flounder larvae Initial discharge survival range: 0  71% for bay anchovy larvae 32  92% for winter flounder larvae Calculation of Entrainment Survival: Discharge survival / Intake survival Confidence intervals / standard deviations: were not presented Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: no Egg survival: based on translucency and hatching success Larval survival: decreased markedly within 3 hours of collection Raw data: were not provided to verify results Temperature effects: no bay anchovy larvae survived at discharge > 35

C Mechanical effects: 18.8% of mortality at discharge temperatures 25.9  27.0

C Quality control: unknown Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 36 March 11, 2003 Pittsburg Power Plant Suisun Bay, CA 1976 Study Stevens and Finlayson,

1978 Sampling: Dates: April 28  July 10 Samples collection frequency: once per week Times of peak abundance: unknown Time: varied, about 25% of all samples collected at night Number of replicates: typically 3 Intake and discharge sampling: paired at closest time and temperature Elapsed collection time: 1  2 minutes Method: 505 micron mech conical nylon plankton net with 0.58 m plastic collecting tubes on cod end; towed net on boat at 0.6 ft/ sec Depth: mid depth Intake location: in river near intake Discharge location: in river near discharge Water quality parameters measured: none DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: unknown Temperature: Intake temperature: 18  30

C Discharge temperature 27  37

C Biocide use was not noted Survival Estimation: Number of sampling events: 7 Total number of samples collected: unknown Total number of organisms collected: 462 ( 585 at north shore control) Number of organisms entrained per year: unknown Fragmented organisms: enumerated in one replicate tow higher proportion of unidentifiable fragments in intake 43% in intake; 19% in discharge Equal number of organisms collected at intake and discharge: more at intake Most abundant species: striped bass Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: not studied Data: was summarized by mean larval length Controls: survival in the intake samples was considered to be the control additional controls in center of river and north shore control site at north shore away from intake had lower mortality rates Initial intake survival range: 49  93% for striped bass Initial discharge survival range: 8  87% for striped bass Calculation of Entrainment Survival: paired discharge survival divided by paired intake survival Confidence intervals / standard deviations: were not presented Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: not studied Larval survival: increased survival with greater larval length Raw data: were not provided to verify results Temperature effects: mortality increased with increase in discharge temperature higher mortality with discharge temp. > 31 and   T > 7

C linear regression showed that half died at temps > 33.3

C 0% survival at temperatures of 38

C Mechanical effects: stated not as much of an effects as temperature; § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 37 Port Jefferson Generating Station Long Island Sound, NY 1978 Study Ecological Analysts Inc. and Ecological Analy, 1978 Sampling: Dates: April 21  26 Samples collection frequency: 4 times in one week Times of peak abundance: unclear if sampling coincided with peak densities Time: 1800  0200 hours Number of replicates: varied between 7  10 per sampling date. Intake and discharge sampling: simultaneous collection, equal number at sites Elapsed collection time: 15 minutes Method: pump ( 2 different types) and larval table Depth: intake: 2 m below mean low water mark discharge: 1 m below mean low water mark Intake location: in front of trash racks of intake of Unit 4 Discharge location: in common seal well structure for Units 3 and 4 Water quality parameters measured: none DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: 4 Temperature: Intake range: 7  9

C Discharge range: 10  18

C   T ranged from 2  11

C Biocide use: sampling coincided with time of no biocide use Survival Estimation: Number of sampling events: 5 Total number of samples collected: 94 Total number of organisms collected: 1104 Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: no, quite different Most abundant species: winter flounder, sand lance, sculpin, American eel, fourbeard rockling eggs Stunned larvae: included in initial survival proportion Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars in water bath for 96 hours Data: was summarized and averaged over the entire sampling period Controls: survival in the intake samples was considered to be the control Initial intake survival range: 42  60% for winter flounder PYSL 11  67% for sand lance PYSL 33  84% sculpin PYSL 25  100% American eel juveniles 11  26% fourbeard rockling eggs Initial discharge survival range: 0  43% for winter flounder PYSL 12  40% for sand lance PYSL 88% for sculpin PYSL 94  96% for American eel juveniles 19  21% fourbeard rockling eggs Calculation of Entrainment Survival: Discharge survival / intake survival Confidence intervals / standard deviations: were not presented. Significant differences were tested between the intake and discharge survival Significantly lower survival in discharge: winter flounder PYSL Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: classified by observation only, based on transparency Larval survival: no information given on length or other life stages Raw data: were provided to verify results Temperature effects: no apparent relationship temperature and survival; low numbers collected at a narrow range of discharge temperatures Mechanical effects: assumed cause of all mortality Quality control: color coded labeling, checks of sorted samples, and SOPs Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 38 March 11, 2003 PG& E Potrero Power Plant San Francisco Bay, CA 1979 Study Ecological Analysts Inc., 1980b Sampling: Dates: January Samples collection frequency: unknown Times of peak abundance: unclear if sampling corresponded with peak densities Time: unknown Number of replicates: unknown Intake and discharge sampling: equal number but timing unknown Elapsed collection time: 15 minutes Method: 2 pumps and larval table with filtered ambient temperature water flow Depth: mid depth Intake location: directly in front of intake skimmer wall Discharge location: at point where discharge enters San Francisco Bay Water quality parameters measured: none DOC and POC measured: no Intake and discharge velocity: unknown Operating Conditions During Sampling: Number of units in operation: unknown Number of pumps in operation: unknown Temperature: Discharge range: 18  19.5

C   T range not presented Biocide use: not used during sampling events Survival Estimation: Number of sampling events: 11 Total number of samples collected: 25 Total number of organisms collected: 1262 Number of organisms entrained per year: estimated for Units 1 3: 3 billion Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: approx. same Most abundant species: Pacific herring Stunned larvae: issue of stunned larvae not discussed in study Dead and opaque organisms: not discussed Latent survival: observed in aerated glass jars in water baths for 96 hours Data: was summarized and averaged over the entire sampling period Controls: survival in the intake samples was considered to be the control Initial intake survival range: 22% for Pacific herring Initial discharge survival range: 16% for Pacific herring Calculation of Entrainment Survival: Discharge survival/ Intake survival Confidence intervals / standard deviations: were not presented. Significant differences were not tested between the intake and discharge survival Survival calculated for species with fewer than 100 organisms collected: no Egg survival: not studied Larval survival: Based on results of this study, an estimate of 75% entrainment survival was used for all species and life stages entrained at this facility under all conditions Raw data: were not provided to verify results Temperature effects: discharge temps < 30

C over 99.5% of time Mechanical effects: most likely cause of mortality due to low temperatures Quality control: unknown Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 39 Quad Cities Nuclear Station Mississippi River, IL 1978 Study Hazleton Environmental Science & Co., 1978 Sampling: Dates: June 19  28 Samples collection frequency: varied Times of peak abundance: unknown Time: afternoon, evening or nighttime hours Number of replicates: varied Intake and discharge sampling: unknown if paired Elapsed collection time: did not exceed 60 seconds Method: from boat, with 0.75 m conical plankton net with 526 µ m mesh and an unscreened 5 L bucket attached Depth: mid depth at intake, near surface at discharge Intake location: intake forebay Discharge location: in discharge canal common to all units; held at discharge temp for 8.5 minutes to simulate passage through canal then cooled to ambient temp. plus 3.5

C before sorting Water quality parameters measured: DO DOC and POC measured: no Intake and discharge velocity: exceed 1 ft/ sec Operating Conditions During Sampling: completely open cycle mode Number of units in operation: power output 41  99%, Unit 1 offline on June 22 Number of pumps in operation: all 3 regardless of power load Temperature: Intake range: 21.5  26.5

C Discharge range: 28.0  39.0

C   T ranged from 5.5  14.8

C Biocide use: not used during sampling Survival Estimation: Number of sampling events: 5 Total number of samples collected: unknown Total number of organisms collected: 2587 Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: more at discharge Most abundant species: freshwater drum and minnows Stunned larvae: included in initial survival proportion Dead and opaque organisms: assumed dead from natural mortality prior to collection and omitted from further analysis; 27% of all sampled Latent survival: observed in aerated glass jars for 24 hours on June 22 23, 26 27 Data: combined by % power of station operation Controls: survival in the intake samples was considered to be the control Initial intake survival range: 0  80% for all species 0  100% for freshwater drum 48  100% for minnows Initial discharge survival range: 0  84% for all species 0  71% for freshwater drum 2  75% for minnows Calculation of Entrainment Survival: Discharge survival/ Intake survival ( minus dead and opaque individuals) When discharge survival was greater than intake survival, the study indicated that entrainment survival could not be calculated, rather than assume 100 percent entrainment survival Confidence intervals / standard deviations: were not presented. Significant differences were tested between the intake and discharge survival Significantly lower survival in discharge: throughout study Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: not presented Larval survival: decreased with increasing power output and discharge temperature 3% survival for all species when the facility operated near full capacity ( 96 99 percent) and discharge temperatures exceeded 37.9 ° C Raw data: were provided to verify results, however replicate sample data not presented Temperature effects: lower survival with higher discharge temperatures > 30

C Mechanical effects: suggest mechanical effects cause 20  25% of mortality Quality control: not discussed Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival A7 40 March 11, 2003 Quad Cities Nuclear Station Mississippi River, IL 1984 Study Lawler Matusky &

Skelly Engineers, 1985 Sampling: Dates: April 25  June 27 July sampling canceled as 100% mortality was suspected Samples collection frequency: weekly Times of peak abundance: unknown Time: unknown Number of replicates: unknown Intake and discharge sampling: unknown if paired Elapsed collection time: unknown Method: from boat, with 0.75 m conical plankton net with 526 µ m mesh and an unscreened 5 L bucket attached Depth: 1.5 m for intake, surface for discharge Intake location: intake forebay Discharge location: in discharge canal; held at collection temperature for 8.5 min. then cooled to 3.5

C above ambient temperature with an ice bath, in all held for over 20 minutes before sorting Water quality parameters measured: none DOC and POC measured: no Intake and discharge velocity: samples collected at < 0.8 ft/ sec Operating Conditions During Sampling: operating at 40.2 to 50.7 % capacity Number of units in operation: Unit 1 offline for refueling; both units offline on May 9 Number of pumps in operation: all 3 on all dates except on May 9 Temperature: Intake range: 11  24.4

C Discharge range: 12  37

C   T ranged from 9.5 to 14.5

C; 1

C on May 9 when offline Biocide use: not used during sampling Survival Estimation: Number of sampling events: 8 Total number of samples collected: unknown Total number of organisms collected: 3967 Number of organisms entrained per year: unknown Fragmented organisms: not discussed Equal number of organisms collected at intake and discharge: approx. same total Most abundant species: freshwater drum, carp and buffalo Stunned larvae: not discussed Dead and opaque organisms: omitted from analysis; assumed dead before collection, 2, 979 opaque individuals were collected ( 75% of total, 87% of all discharge sample. range: 0 to 99% in samples) None were found to be dead and opaque in discharge on May 9 when offline and   T was 1 ° C. Latent survival: not discussed Data: combined by species and sampling date Controls: survival in the intake samples was considered to be the control Initial intake survival range: results not presented, only number alive 10  81% were dead and opaque Initial discharge survival range: results not presented, only number alive 24  99% were dead and opaque Calculation of Entrainment Survival: Discharge survival / Intake survival Confidence intervals / standard deviations: were not presented. Significant differences were not tested due to low numbers collected Survival calculated for species with fewer than 100 organisms collected: yes Egg survival: not studied Larval survival: too little information to make any assumption of survival Raw data: were not provided to verify results; totals collected per species not presented; actual numbers of dead and opaque not provided Temperature effects: no sampling in July when discharge temps > 37

C Mechanical effects: not discussed Quality control: 100% reanalysis quality control Peer review: not mentioned, study was conducted for the facility § 316( b) Existing Facilities Benefits Case Studies, Part A: Evaluation Methods Chapter A7: Entrainment Survival March 11, 2003 A7 41 Roseton Generating Station Hudson River, NY 1975 Study Ecological Analysts,