# Compilation of California Coastal Power Plant Entrainment

and Impingement Estimates for California State Water Resources Control Board Staff Draft Issue Paper on Once
through Cooling

Prepared for: Prepared by: Dr. Michael Foster John Steinb eck Coastal Solutions Group 356 Miramar Ln. 911 Elkhorn Rd. Pismo Beach, CA 93449 Watsonville, CA 95076 jsteinbeck@charter.net



# Entrainment Estimates
The entrainment data presented in Table 1 were mostly compiled from recent studies of cooling water systems at power plants in California. The design cooling water flows and actual average flows for the 2000

–2005 period used in some of the calculations were compiled from several sources (Appendix A). Entrainment estimates are only presented for larval fish es because this is the only taxonomic group and life stage that was sampled consistently across all of the facilities. The table presents two sets of entrainment estimates. The first set is calculated using the annual average larval concentrations from the recent studies. The entrainment estimates were calculated by multiplying the larval concentrations by the total annual design and by the average 2000

– 2005 flows. The other set of entrainment estimates is from the published studies, which did not in all ca ses present estimates for both design and actual flows (shown as ‘nc’ in Table 1 ). The only plants where recent representative data were not available were the Contra Costa and Pittsburg power plants located in the Sacramento

- San Joaquin Delta (Delta) syst em. The table does present annual entrainment estimates for those two plants from studies completed thirty years ago in 1978

– 1979; no estimates based on the larval concentration from those studies were calculated because there have been so many long

- term c hanges in flows and species composition within the Delta system that the estimates are unlikely to be representative of current conditions. The entrainment estimates calculated using the average annual larval concentrations are very similar to the publish

ed entrainment estimates for the two nuclear plants (SONGS and DCPP) and units at other plants that are operating at a high capacity factor. There are more differences between the two sets of estimates for plants and units that are operating at a low capac ity factor. This is due to seasonal changes in larval concentrations that can significantly affect estimates of annual entrainment, especially when peak capacity is occurring during periods with high concentrations of larvae. The seasonality in larval abun dances varies between central and southern California, and also between open coast and protected bays and harbors ( Figures 1 and 2 ).

## CA Power Plant CWS Estimates

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# Impingement Estimates
Similar to entrainment, the impingement data presented in Table 2 were mostly from recent studies at power plants in California using the same flow data used in Table 1 and documented in Appendix A. Impingement estimates are only presented for fishes because this is the only taxonomic group that was sampled consistently across all of the facilities. The table presents two sets of impingement estimates for both numbers and biomass of fishes. The first set is calculated using the annual average impingement rates during normal operations calculated from the recent studies. The total annual normal operations impingement estimates were calculated by multiplying the impingement rates by the total annual design and average 2000

–2005 flows. These impingement estimates for normal operations would be added to the average annual impingement during heat treatments for the plants where heat treatments are used for controlling biofouling inside the cooling system. The other set of impingement estimates is from published studies, which did not in all cases present estimates for both design and actual flows (shown as ‘nc’ in Table 2). These estimates include both normal operations and heat treatment impingement. The only plants where recent representative data were not available were the Contra Costa and Pittsburg power plants located in the Delta system. The table does present annual impingement estimates for those two plants from studies completed thirty years ago in 1978

– 1979.



# Intake Structure
Information on the intake structures at the California power plants is presented in Table 3 . The various fish protection measures are listed and details provided on the openings of the cooling water systems where they draw water. This information could be used in evaluating the potential for entrapment of marine mammals and reptiles into the systems. Note that the only plants with variable speed drives that allow flow to be adjusted to meet load capacity are installed at the Contra Costa and Pittsburg power plants in the Delta. San Onofre is the only plant with a sophisticated fish return system.



# References (see Appendix B)
Ecological Analysts. 1981a. Contra Costa Power Plant cooling water intake structure 316(b) demonstration. Prepared for Pacific Gas & Electric Co., San Francisco, CA. Ecological Analysts. 1981b. Pittsburg Power Plant cooling water intake structure 316(b) demonstra

tion. Prepared for Pacific Gas & Electric Co., San Francisco, CA. ENSR Corporation. 2008a. Draft Impingement Mortality and/or Entrainment Characterization Study

- Reliant Energy Mandalay Generating Station (NPDES Permit No.CA0001180). Prepared for Reliant En

ergy.

## CA Power Plant CWS Estimates

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# ENSR Corporation. 2008b. Draft Impingement Mortality and/or Entrainment Characterization Study

- Reliant Energy Ormond Beach Generating Station (NPDES Permit No. CA0001198). Prepared for Reliant Energy. MBC Applied Environmental Sciences. 2008. San Ono fre Nuclear Generating Station Clean Water Act Section 316(b) impingement mortality and entrainment characterization study. In EPRI. 2008. Comprehensive Demonstration Study for Southern California Edison’s San Onofre Nuclear Generating Station. Prepared fo r Southern California Edison, San Clemente, CA. MBC Applied Environmental Sciences and Tenera Environmental. 2005. AES Huntington Beach Generating Station entrainment and impingement study final report. Prepared for AES Huntington Beach L.L.C. and Califor nia Energy Commission, Sacramento, CA. MBC Applied Environmental Sciences and Tenera Environmental. 2008a. Alamitos Generating Station Clean Water Act Section 316(b) impingement mortality and entrainment characterization study. Prepared for AES Alamitos L .L.C., Long Beach, CA. MBC Applied Environmental Sciences and Tenera Environmental. 2008b. Redondo Beach Generating Station Clean Water Act Section 316(b) impingement mortality and entrainment characterization study. Prepared for AES Redondo Beach L.L.C., Redondo Beach, CA. MBC Applied Environmental Sciences, Tenera Environmental, and URS Corp. 2008a. Haynes Generating Station Clean Water Act Section 316(b) impingement mortality and entrainment characterization study. Prepared for City of Los Angeles Dept. of Water and Power, Los Angeles, CA. MBC Applied Environmental Sciences, Tenera Environmental, and URS Corp. 2008b. Harbor Generating Station Clean Water Act Section 316(b) impingement mortality and entrainment characterization study. Prepared for City of Los Angeles Dept. of Water and Power, Los Angeles, CA. MBC Applied Environmental Sciences, Tenera Environmental, and URS Corp. 2008c. Scattergood Generating Station Clean Water Act Section 316(b) impingement mortality and entrainment characterization study . Prepared for City of Los Angeles Dept. of Water and Power, Los Angeles, CA. Tenera Environmental. 1988. Diablo Canyon Power Plant. Cooling Water Intake Structure, 316(b) Demonstration. Prepared for Pacific Gas & Electric Co., San Francisco, CA.

Tenera En

vironmental. 2000a. Diablo Canyon Power Plant. 316(b) Demonstration report. Prepared for Pacific Gas & Electric Co., San Francisco, CA.

## CA Power Plant CWS Estimates

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# Tenera Environmental. 2000b. Moss Landing Power Plant modernization project 316(b) resource assessment. Prepared for Duke Energy Moss Landing LLC, Oakland, CA. Tenera Environmental. 2001. Morro Bay Power Plant modernization project: 316(b) resource assessment. Prepared for Duke Energy Morro Bay LLC, Oakland, CA. Tenera Environmental. 2004. South Bay Power Plant cooling wat er system effects on San Diego Bay, Volume II: Compliance with Section 316(b) of the Clean Water Act for the South Bay Power Plant. Prepared for Duke Energy South Bay LLC, Chula Vista, CA.
Tenera Environmental. 2005. Potrero Power Plant. 316(b) Entrainment Characterization Report for Potrero Power Plant Unit 3. Submitted to Mirant Potrero LLC, San Francisco, CA. Tenera Environmental. 2007a. Potrero Power Plant. Impingement Mortality Study Data Report. Submitted to Mirant Potrero LLC, San Francisco, CA.

Tene ra Environmental. 2007b. Moss Landing Power Plant Units 1&2 and Units 6&7 Impingement Study Data Report. Prepared for Moss Landing Power Plant, Moss Landing, CA.
Tenera Environmental. 2008. Cabrillo Power I LLC, Encina Power Station Clean Water Act Section 316(b) impingement mortality and entrainment characterization study. Effects on the biological resources of Agua Hedionda Lagoon and the nearshore ocean environment. Prepared for Cabrillo Power I LLC, Carlsbad, CA. Tenera Environmental and MBC Applied Env ironmental Sciences. 2008. El Segundo Generating Station Clean Water Act Section 316(b) impingement mortality and entrainment characterization study. Prepared for El Segundo Power LLC, El Segundo, CA.

## CA Power Plant CWS Estimates

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# Table 1 . Entrainment estimates for larval fishes from California coastal power plants. Estimates include calculated values from design and average annual 2000

–

2005 flows using larval concentrations from recent studies and also estimates from recently published entrainment studies. Studies where entrainment e

stimates were not calculated for design or actual flow conditions during the study are indicated as “nc”. References used in compiling the information in the table are provided in Appendix B.

Plant Design Flow (mgd) Average Flow

(mgd) based on 2000-2005 data Average Larval Fish Concentration (# per m 3

) Based on Average Concentration and Design Flow Based on Average

Concentration and Average Flow Based on Study

Results (Design flow) Based on Study

Results (Actual flow) Alamitos Generating Station Units 1&2 207 121 2.6096 748,143,755 437,759,583 nc 121,970,937 Alamitos Generating Station Units 3&4 392 281 2.6096 1,414,663,347 1,013,512,946 1,109,972,442 728,944,910 Alamitos Generating Station Units 5&6 674 413 2.6338 2,454,486,046 1,503,067,179 nc 835,841,962 Contra Costa Power Plant Units 6&7 440 257 nc 95,110,000 Diablo Canyon Power Plant 2,528 2,287 0.5051 1,765,532,613 1,596,971,533 nc 1,481,948,383 El Segundo Generating Station Units 1&2 207 69 0.5160 147,937,420 49,426,499 nc 35,743,328 El Segundo Generating Station Units 3&4 399 265 0.5160 284,368,596 189,249,580 276,934,913 186,532,003 Encina Power Plant 857 621 3.6844 4,365,717,854 3,161,960,103 4,494,849,115 3,627,641,744 Harbor Generating Station 108 59 1.0464 156,251,732 85,429,045 153,331,013 65,298,000 Haynes Generating Station 968 258 3.2500 4,348,289,797 1,159,409,807 4,527,644,084 3,649,208,392 Huntington Beach Generating Station 514 179 0.4216 299,581,897 104,316,376 344,570,635 nc Mandalay Generating Station 253 234 0.4000 140,164,653 129,172,964 141,736,337 33,422,317 Morro Bay Power Plant 668 257 0.8991 830,359,489 318,873,127 859,337,744 nc Moss Landing Power Plant Units 1&2 361 193 1.1700 583,974,343 311,469,330 522,319,740 nc Moss Landing Power Plant Units 6&7 865 387 0.7813 934,455,149 418,259,815 888,204,836 nc Ormond Beach Generating Station 685 521 0.0446 42,267,607 32,126,547 40,810,043 6,351,783 Pittsburg Power Plant Units 5&6 462 274 nc 175,230,000 Potrero Power Plant 231 193 0.9490 303,453,048 252,788,154 289,731,811 nc Redondo Generating Station Units 5&6 217 51 1.1847 354,625,241 83,019,162 356,000,276 101,659,379 Redondo Generating Station Units 7&8 675 254 0.8276 772,030,657 290,738,095 744,808,585 189,537,344 San Onofre Nuclear Generating Station Unit 2 1,219 1,139 1.9649 3,310,586,813 3,094,578,330 nc 3,555,787,272 San Onofre Nuclear Generating Station Unit 3 1,219 1,154 1.9649 3,310,586,813 3,136,241,271 nc 3,261,783,562 Scattergood Generating Station 495 309 0.7387 505,973,132 315,565,914 524,202,652 365,258,133 South Bay Power Plant 601 417 2.8925 2,403,523,588 1,667,044,144 2,420,527,779 nc
nc = not calculated in report no recent representative data available

no recent representative data available Annual Larval Entrainment Estimate

## CA Power Plant CWS Estimates

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# Table 2 . Impingement estimates for fish numbers and biomass ( lb) from California coastal power plants. Estimates include calculated values for normal operations for design and average annual 2000

– 2005 flows using impingement rates from recent studies. For plants using heat treatments these calculated estimates would need to include an estimate of the total impingement during heat treatment events calculate using the average annual impingement and the average numbers of heat treatments. The impingement estimates from recently published impingement mortality studies in clude heat treatment. Studies where impingement estimates were not calculated for design or actual flow conditions during the study are indicated as “nc”. References used in compiling the information in the table are provided in Appendix B.

Plant Design Flow (mgd) Average Flow (mgd) based on 2000-2005 data Average #

fish per million gal Average

Biomass (lbs) fish per million gal Based on

Count and Design Flow Based on

Biomass (lbs) and Design Flow Based on

Count and Average Flow Based on

Biomass (lbs) and Average Flow Average #

per HT Average

Biomass (lb) per HT Average

Number of HT per year (2000- 2005) Design

Flow Total # Estimate Design Flow

Total Biomass (lb) Estimate Actual

Flow Total # Estimate Actual Flow

Total Biomass (lb) Estimate Alamitos Generating Station Units 1&2 207 121 n/a n/a n/a Alamitos Generating Station Units 3&4 392 281 n/a n/a n/a Alamitos Generating Station Units 5&6 674 413 n/a n/a n/a Contra Costa Power Plant Units 6&7 440 257 n/a n/a n/a

— — 107,621 2,741 Diablo Canyon Power Plant 2,528 2,287 0.0058 0.0009 5,330 785 4,821 710 n/a n/a n/a nc nc nc nc El Segundo Generating Station Units 1&2 207 69 0.0103 0.0035 779 265 260 89 227.25 72.18 1.3 nc nc 186 63 El Segundo Generating Station Units 3&4 399 265 0.0220 0.0068 3,209 995 2,136 662 229.00 94.60 3.7 2,521 542 1,527 473 Encina Power Plant 857 621 0.6128 0.0256 191,824 8,016 138,932 5,806 15,831.83 747.70 6 289,562 12,878 215,583 9,609 Harbor Generating Station 108 59 0.4945 0.1622 19,508 6,399 10,666 3,498 n/a n/a n/a 19,861 6,478 8,851 2,903 Haynes Generating Station 968 258 0.1893 0.0041 66,901 1,462 17,838 390 n/a n/a n/a 56,613 1,227 53,442 1,168 Huntington Beach Generating Station 514 179 0.4079 0.0227 76,582 4,270 26,666 1,487 5,887.00 338.70 4.8 nc nc 51,082 2,848 Mandalay Generating Station 253 234 0.7940 0.0299 73,497 2,771 67,733 2,553 101.90 4.20 1.4 30,347 1,308 8,979 199 Morro Bay Power Plant 668 257 0.3497 0.0140 85,315 3,419 32,763 1,313 n/a n/a n/a nc nc 78,139 2,957 Moss Landing Power Plant Units 1&2 361 193 0.5804 0.0058 76,526 762 40,816 406 n/a n/a n/a 75,133 804 57,554 600 Moss Landing Power Plant Units 6&7 865 387 1.7895 0.0287 565,390 9,071 253,067 4,060 n/a n/a n/a 135,699 2,297 118,778 2,033 Ormond Beach Generating Station 685 521 0.0711 0.0164 17,806 4,094 13,534 3,112 677.80 87.20 4.5 7,821 844 517 76 Pittsburg Power Plant Units 5&6 462 274 n/a n/a nc nc 220,364 2,580 Potrero Power Plant 231 193 1.5090 0.0337 127,464 2,847 106,182 2,371 n/a n/a n/a 146,098 3,035 108,727 2,446 Redondo Generating Station Units 5&6 217 51 0.0075 0.0034 593 268 139 63 10.08 7.32 2 263 71 133 60 Redondo Generating Station Units 7&8 675 254 0.0240 0.0085 5,913 2,084 2,227 785 157.50 37.90 4.8 2,910 1,315 1,101 388 San Onofre Nuclear Generating Station Unit 2 1,219 1,139 7.5 San Onofre Nuclear Generating Station Unit 3 1,219 1,154 7.8 Scattergood Generating Station 495 309 0.8226 0.0814 148,840 14,727 92,829 9,185 10,155.00 788.40 5.2 108,843 11,619 95,241 9,422 South Bay Power Plant 601 417 1.5921 0.0049 349,490 1,082 242,401 751 n/a n/a n/a 385,588 1,226 nc nc nc = not calculated in report n/a = not applicable 1,322,490 Reported Values

627.80 1.5787 0.0335 Annual Normal Operations Impingement Estimate Heat Treatments (HT)

2,249 nc 52,106

1,405,342 29,854 81,419 3,514

no recent representative data available nc

no recent representative data available 0.1750 0.0076

28,746 29,013 1,252

28,094 2,494.00 nc 1,353,158 nc

## CA Power Plant CWS Estimates

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# Table 3 . In

formation on cooling water intake system design at California power plants. Acronyms used for the various intake components and fish protection systems and provided below the table.

Region Plant Intake Location Type of Intake Screening or Fish Protection Devices* Size of openings at Entrance to Intake Vertical Distance from Riser to VC Mammal Exclusion

Bars Offshore? NoCal Contra Costa Power Plant tidal river shoreline BR-TS-VFD Bar racks 3.5" spacing n/a n/a NoCal Pittsburg Power Plant tidal river shoreline BR-TS-VFD Bar racks 3.5" spacing n/a n/a NoCal Potrero Power Plant bay/harbor shoreline BR-TS Bar racks 3.5" spacing n/a n/a NoCal Moss Landing Power Plant Units 1&2 bay/harbor shoreline BR-TS Bar racks 3.5" spacing n/a n/a NoCal Moss Landing Power Plant Units 6&7 bay/harbor shoreline BR-TS Bar racks 3" spacing n/a n/a NoCal Morro Bay Power Plant bay/harbor shoreline BR-TS bar racks 4" on center n/a n/a NoCal Diablo Canyon Power Plant ocean shoreline BR-TS bar racks 3" on center n/a n/a SoCal Mandalay Generating Station bay/harbor canal BR-SS bar racks 2.5" spacing n/a n/a SoCal Ormond Beach Generating Station ocean offshore VCap-BR-TS 4' at VCap with bars every 18" 4' 18" spacing SoCal Scattergood Generating Station ocean offshore VCap-BR-TS 5' at VCap with bars every 9" 5' 9" spacing SoCal El Segundo Generating Station Units 1&2 ocean offshore VCap-BR-TS 2' at VCap 2' ? SoCal El Segundo Generating Station Units 3&4 ocean offshore VCap-BR-TS 3' at VCap 3' ? SoCal Redondo Generating Station Units 5&6 bay/harbor offshore VCap-BR-TS 4' at VCap with bars every 18" 4' 18" spacing SoCal Redondo Generating Station Units 7&8 bay/harbor offshore VCap-BR-TS 4' at VCap with bars every 18" 4' 18" spacing SoCal Harbor Generating Station bay/harbor shoreline BR-TS bar racks 4.5" on center n/a n/a SoCal Haynes Generating Station tidal river canal BR-TS/SS bar racks 6" on center n/a n/a SoCal Alamitos Generating Station Units 1&2 bay/harbor shoreline BR-TS bar racks 3" spacing n/a n/a SoCal Alamitos Generating Station Units 3&4 bay/harbor shoreline TS no bar racks n/a n/a SoCal Alamitos Generating Station Units 5&6 bay/harbor shoreline BR-TS bar racks 3" spacing n/a n/a SoCal Huntington Beach Generating Station ocean offshore VCap-BR-TS 5' at VCap with bars every 18" 5' 18" spacing SoCal San Onofre Nuclear Generating Station Unit 2 ocean offshore VCap-Vanes-Fish Elevator-BR-TS 7' at VCap 7' No SoCal San Onofre Nuclear Generating Station Unit 3 ocean offshore VCap-Vanes-Fish Elevator-BR-TS 7' at VCap 7' No SoCal Encina Power Plant bay/harbor shoreline BR-TS bar racks 3.5" on center n/a n/a SoCal South Bay Power Plant bay/harbor shoreline BR-TS bar racks 3" spacing n/a n/a * - VCap = velocity cap, BR = bar racks, TS = traveling screens, SS = Slide screens, Vanes = structures inside intake to divert fishes, VFD = variable frequency drive pumps

## CA Power Plant CWS Estimates

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# 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecLarvalFishConcentration(abundanceper1.0m3) 

# Larval Fish Concentrations by Month at

Southern California Power Plant OTC Intake

Bay

- Harbor Open Coast

Figure 1 . Total concentration of larval fishes by month at OTC intake s in southern California. Data sources based on most recent 316(b) sampling conducted at each power facility. Plants combined for bay

- harbor concentrations were South Bay, Encina, Haynes, Alamitos, and Harbor, and the plants combined for the open coast con centrations were San Onofre, Huntington Beach, Redondo Beach, El Segundo, and Scattergood.

## CA Power Plant CWS Estimates

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# 0.0 0.5 1.0 1.5 2.0

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov DecLarvalFishConcentration(abundanceper1.0m3) 

# Larval Fish Concentrations by Month at

Central/Northern California Power Plant OTC Intake

Bay

- Harbor Open Coast

Figure 2 . Total concentration of larval fishes by month at OTC intakes in central California. Data sources based on most recent 316(b) sampling conducted at each power facility. Plants combined for bay

- harbor concentrations were Morro Bay, Moss Landing, and Potrero, and the plants used for the open coast concentrations was Diablo Canyon.

## CA Power Plant CWS Estimates

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# Appendix A. Sources for cooling water data used in calculations of entrainm ent and impingement estimates.

Plant Design Flow (mgd) Average Flow

(mgd) based on 2000-2005 Data Sources Alamitos Generating Station Units 1&2 207 121 data from SWRCB staff - 2000-05 actual monthly flows Alamitos Generating Station Units 3&4 392 281 data from SWRCB staff - 2000-05 actual monthly flows Alamitos Generating Station Units 5&6 674 413 data from SWRCB staff - 2000-05 actual monthly flows Contra Costa Power Plant Units 6&7 440 257 data from plant staff - daily flows for 2000-2005 Diablo Canyon Power Plant 2,528 2,287 flows from plant source complete for 2000-05 El Segundo Generating Station Units 1&2 207 69 data from SWRCB staff - daily flows for 2000-2005 El Segundo Generating Station Units 3&4 399 265 data from SWRCB staff - daily flows for 2000-2005 Encina Power Plant 857 621 flows from plant source complete for 2000-05 Harbor Generating Station 108 59 data from SWRCB staff - 2000-01 actual monthly flows, 2002-05 daily flows Haynes Generating Station 968 258 data from SWRCB staff - 2000-01 actual monthly flows, 2002-05 daily flows, 2005 missing for Units 3&4 Huntington Beach Generating Station 514 179 data from SWRCB staff - 2004-05 actual monthly flows, 2000-03 calculated from megawatt output Mandalay Generating Station 253 234 data from SWRCB staff - 2000-05 actual monthly flows Morro Bay Power Plant 668 257 flows from plant source complete for 2000-05 Moss Landing Power Plant Units 1&2 361 193 flows from plant source complete for 2000-05 Moss Landing Power Plant Units 6&7 865 387 flows from plant source complete for 2000-05 Ormond Beach Generating Station 685 521 data from SWRCB staff - 2000-05 actual monthly flows Pittsburg Power Plant Units 5&6 462 274 data from plant staff - 2000-05 daily flows
Potrero Power Plant 231 193 data from SWRCB staff - 2000-05 actual monthly flows - also plant data provided same average Redondo Generating Station Units 5&6 217 51 data from SWRCB staff - daily flows for 10/1/01-9/30/02 and 1/1/03-12/31/05 Redondo Generating Station Units 7&8 675 254 data from SWRCB staff - daily flows for 10/1/01-9/30/02 and 1/1/03-12/31/05 San Onofre Nuclear Generating Station Unit 2 1,219 1,139 data from SWRCB staff - 2004-05 actual monthly flows, 2000 and 2003 calculated from megawatt output San Onofre Nuclear Generating Station Unit 3 1,219 1,154 data from SWRCB staff - 2004-05 actual monthly flows, 2000 and 2003 calculated from megawatt output Scattergood Generating Station 495 309 data from SWRCB staff - 2000 -2005 actual monthly flows South Bay Power Plant 601 417 flows from plant source complete for 2000-05

## CA Power Plant CWS Estimates

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# Appendix B. References and information on studies used in compiling the data presented in Tables 1 and 2.

Plant Entrainment collection period & frequency / Reference Impingemement collection period & frequency / Reference Alamitos Generating Station Units 1&2 Jan-Dec 2006, bi-weekly / MBC and Tenera 2008a Jan 2006 - Dec 2006; weekly / MBC and Tenera 2008a Alamitos Generating Station Units 3&4 Jan-Dec 2006, bi-weekly / MBC and Tenera 2008a Jan 2006 - Dec 2006; weekly / MBC and Tenera 2008a Alamitos Generating Station Units 5&6 Jan-Dec 2006, bi-weekly / MBC and Tenera 2008a Jan 2006 - Dec 2006; weekly / MBC and Tenera 2008a Contra Costa Power Plant Apr 1978 - Apr 1979, weekly / Ecological Analysts 1981a Apr 1978 - Apr 1979; weekly sampling / Ecological Analysts 1981a Diablo Canyon Power Plant Oct 1996 - Jun 1999, weekly / estimates from Oct 96-Oct 98 Tenera 2000a Feb 1985 - Mar 1986; weekly sampling / Tenera 1988 El Segundo Generating Station Units 1&2 Jan-Dec 2006, monthly / Tenera and MBC 2008 Jan 2006 - Dec 2006; monthly / Tenera and MBC 2008 El Segundo Generating Station Units 3&4 Jan-Dec 2006, monthly / Tenera and MBC 2008 Jan 2006 - Dec 2006; monthly / Tenera and MBC 2008 Encina Power Plant Jun 2004 - May 2005, monthly / Tenera 2008 Jun 2004 - Jun 2005; weekly / Tenera 2008 Harbor Generating Station Jan-Dec 2006, bi-weekly / MBC, Tenera, and URS 2008b Jan 2006 - Dec 2006; weekly / MBC, Tenera, and URS 2008b Haynes Generating Station Jan-Dec 2006, bi-weekly / MBC, Tenera, and URS 2008a Jan 2006 - Dec 2006; weekly / MBC, Tenera, and URS 2008a Huntington Beach Generating Station Sep 2003 - Aug 2004, weekly / MBC and Tenera 2005 Jul 2003 - Jul 2004; weekly / MBC and Tenera 2005
Mandalay Generating Station Feb 2006 - Feb 2007; biweekly / ENSR Corp. 2008a Feb 2006 - Feb 2007; biweekly / rates and totals from ENSR Corp. 2008a; average rates and HT data from NPDES data supplied by MBC Morro Bay Power Plant Jan 2000 - Dec 2000, weekly / Tenera 2001 Sep 1999 - Sep 2000; weekly / Tenera 2001 Moss Landing Power Plant Units 1&2 Mar 1999 - Feb 2000, weekly / Tenera 2000b Nov 2005 - Nov 2006; weekly / Tenera 2007b Moss Landing Power Plant Units 6&7 Mar 1999 - Feb 2000, weekly / Tenera 2000b Nov 2005 - Nov 2006; weekly / Tenera 2007b

Ormond Beach Generating Station Feb 2006 - Feb 2007; biweekly / ENSR Corp. 2008b Feb 2006 - Feb 2007; biweekly / rates and totals from ENSR Corp. 2008b; average rates and HT data from NPDES data supplied by MBC Pittsburg Power Plant Units 5&6 Mar 1978 - Mar 1979, weekly; Ecological Analysts 1981b Mar 1978 - Mar 1979; weekly sampling / Ecological Analysts 1981b Potrero Power Plant Jan 2001 - Feb 2002, weekly (Dec-Mar) or monthly Apr-Nov) / Tenera 2007a May 2006 - May 2007; weekly / Tenera 2007a Redondo Generating Station Units 5&6 Jan 2006 - Jan 2007, monthly / MBC and Tenera 2008b Jan 2006 - Jan 2007; weekly / MBC and Tenera 2008b Redondo Generating Station Units 7&8 Jan 2006 - Jan 2007, bi-weekly / MBC and Tenera 2008b Jan 2006 - Jan 2007; weekly / MBC and Tenera 2008b San Onofre Nuclear Generating Station Unit 2 Mar 2006 - Apr 2007; biweekly inside plant, monthly at offshore intakes / MBC 2008 Mar 2006 - May 2007; biweekly / MBC 2008 San Onofre Nuclear Generating Station Unit 3 Mar 2006 - Apr 2007; biweekly inside plant, monthly at offshore intakes / MBC 2008 Mar 2006 - May 2007; biweekly / MBC 2008 Scattergood Generating Station Jan 2006 - Jan 2007, bi-weekly / MBC, Tenera, and URS 2008c Jan 2006 - Jan 2007; weekly / MBC, Tenera, and URS 2008c South Bay Power Plant Feb 2001 - Jan 2002, monthly / Tenera 2004 Dec 2002 - Nov 2003; weekly / Tenera 2004