## F I N A L R E P O R T



# A DDENDUM 

# T O 

# E VALUATION OF THE 

# H AYNES 

# G ENERATING 

# S TATION WITH 

# R ESPECT TO

THE 

# C LEAN 

# W ATER 

# A CT 

# S ECTION 

# 316(b) R EQUIREMENTS 

# P ROVIDING 

# A C URRENT 

# A SSESSMENT OF 

# A LTERNATIVE 

# T ECHNOLOGIES AND 

# O PERATIONAL 

# M EASURES

Prepared by 

### Alden Research Laboratory, Inc.

EPRI MBC Applied Environmental Sciences Tenera Environmental, Inc. URS Corporation

for

City of Los Angeles Department of Water and Power 111 N. Hope Street Los Angeles, California 90012-2607

April 6, 2007An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

i 

## TABLE OF CONTENTS

S ECTION 

## P AGE



### 1.0 INTRODUCTION.................................................................................................... 1-1

2.0 ADDITIONAL INFORMATION CURRENTLY AVAILABLE........................ 2-1

2.1 H N GS R E

- POWERING P ROJECT .................................................................................2-1

2.2 A DDITIONAL T ECHNOLOGIES ....................................................................................2-1

2.3 I MPINGEMENT M ORTALITY AND E NTRAINMENT C HARACTERIZATION ....................2-2

2.4 C OSTS 2-2

2.5 S ECOND C IRCUIT C OURT D ECISION ..........................................................................2-3



### 3.0 ENTRAINMENT REDUCTION OPTIONS......................................................... 3-1

3.1 F INE

- MESH M ODIFIED T RAVELING S CREENS ............................................................3-1

3.2 M ODULAR I NCLINED S CREENS ..................................................................................3-3

3.3 F LOW R EDUCTION .....................................................................................................3-3

3.4 C LOSED

- CYCLE C OOLING ..........................................................................................3-4

3.5 A DDITIONAL T ECHNOLOGIES ....................................................................................3-5



### 4.0 IMPINGEMENT MORTALITY REDUCTION OPTIONS............................... 4-1

4.1 C OARSE

- MESH M ODIFIED T RAVELING S CREENS ......................................................4-1

4.2 M ODULAR I NCLINED S CREENS ..................................................................................4-1

4.3 F LOW R EDUCTION .....................................................................................................4-2

4.4 C LOSED

- CYCLE COOLING ..........................................................................................4-2

4.5 A DDITIONAL T ECHNOLOGIES ....................................................................................4-2



### 5.0 COST UPDATE ....................................................................................................... 5-1

6.0 DATA GAPS AND UNCERTAINTIES................................................................. 6-1

7.0 CONCLUSIONS ...................................................................................................... 7-1

L IST OF 

### A TTACHMENTS

ATTACHMENT A

- S UMMARY OF 2004 EVALUATION OF H NGS
ATTACHMENT B

- LADWP R ESTORATION O PTIONS
ATTACHMENT C

- FLOW CALCULATIONS

ATTACHMENT D

- FISH MORPHPMETRY AND SCREEN MESH HEADLOSS

ATTACHMENT E

- POTENTIAL FISH RETURN CLEANING SYSTEMS

ATTACHMENT F

- NARROW-SLOT, WEDGEWIRE SCREEN CONCEPTUAL DESIGN



### L IST OF 

### T ABLES

T ABLE 2-1. P ERTINENT P ROJECT D ATA (R EVISED T ABLE 2-1 FROM THE I NITIAL R EPORT )..............2-5

T ABLE 2-2. R EVISED T ABLE 2-3 FROM THE I NITIAL E VALUATION

– C OMPARISON OF P ERCENT
C OMPOSITION OF E NTRAINED L ARVAE L ENGTHS C OLLECTED AT H N GS...................................2-8

T ABLE 2-3. I NITIAL S CREENING OF F ISH P ROTECTION A LTERNATIVES AT H N GS (R EVISED

T ABLE 3-1 FROM THE I NITIAL E VALUATION )...............................................................................2-9

T ABLE 5-1. A LDEN ’ S A PPRAISAL L EVEL C OSTS OF E VALUATED A LTERNATIVES .............................5-2An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

1-1 

## 1.0 INTRODUCTION

In December 2004, Alden Research Laboratory, Inc. (Alden), under contra ct to the Electric Power Research Institute (EPRI), developed a report entitled “Eva luation of the Haynes Generating Station with respect to the Environmental Protection Agency’s 316(b) Ru les for Existing Facilities” for the Los Angeles Department of Water and Power (LADWP). This report provided an assessment of the universe of technologies available for consideration for fish pr otection at steam generating stations and resulted in a limited number of technologies and operational measur es that were considered appropriate for the Haynes Generating Station (HnGS). A summ ary of the results of the 2004 evaluation is provided in Attachment A.

HnGS is subject to both the impingement mortality and entrainme nt (IM&E) reduction performance standards. In addition to the entrainment reduction technologies, whi ch also generally provide a benefit for impingeable-sized organisms, the original assessment also included impingement only alternatives. This distinction will be maintained in this report.

The technologies evaluated in the initial detailed investig ation fall into four categories: physical barriers, collection systems, diversion systems, and behavio ral barriers. Diversion systems and behavioral barriers require the ability of the organisms to swi m away. Entrainable organisms lack the sustained swimming ability to respond effectively to these sy stems; therefore, diversion systems and

behavioral barriers were eliminated from consideration to meet the entrainment reduction standard. Three technologies (i.e., cylindrical wedgewire screens, fine- mesh traveling screens, and modular inclined screens) were considered as entrainment and entrainment /impingement reducing options at HnGS. The Cooling Water Intake System (CWIS) location and hydra ulic conditions at HnGS make this site unsuitable for wedgewire screens to be installed i n the conventional manner (i.e., upstream of the CWIS at the bar racks and the use of air-burst backwash in the marina).

As discussed below, more current information allows for re-conside ration of technologies and operational measures. This report will serve as an Addendum to t he 2004 report. The 2004 evaluation also included a discussion of restoration projects. An update to the restoration evaluation is provided in Attachment B. To develop this Addendum, Alden consulte d with EPRI, MBC Applied Environmental (MBC), Tenera Environmental, Inc. (Tenera), and URS Corpor ation (URS).An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

2-1 

## 2.0 ADDITIONAL INFORMATION CURRENTLY AVAILABLE

The following new information has been assessed as it relates to Alden’s original evaluation:

• HnGS has completed a re-powering project since the 2004 report;

• Additional technologies have become available;

• LADWP has completed a one-year IM&E study;

• Costs can be updated to 2006 values; and

• The Second Circuit Court (Court) issued a decision (Decision) on v arious components of the

Phase II Rule.

Table 2-1 is a revised and updated version of Table 2-1 in the in itial report. This table reflects changes in flow as a result of the replacement of Units 3 and 4 with U nit 8 during re-powering. Also, velocity calculations are provided in Attachment C.

A discussion of the impacts of these new data on the alternati ves previously evaluated and additional alternatives that are available for HnGS is presented in the fol lowing sections.



### 2.1 H N 

### GS R E



### - POWERING 

### P ROJECT

Units 3 and 4 have been replaced by Units 8, 9, and 10 and are described a s a 2+1 combined cycle unit (Unit 8). However, the new unit utilizes the existing intakes for the retired units. The original pumps have been replaced with lower flow capacity pumps. Each of the ne w pumps provides 40,000 gallons per minute (gpm), as opposed to the original 48,000 gpm. This flow reduction res ults in approximately a 5% lower flow than prior to re-powering and slightly lower velocit ies within the CWIS. The flow reduction can be used to take credit toward meeting the IM&E reduction performance standards under the calculation baseline. However, the credit does not change any of Al den’s original technology

assessments.



### 2.2 A DDITIONAL 

### T ECHNOLOGIES

In the 2004 report, there were four technologies characterized as “emerging t echnologies”:

• Beaudrey’s Fish Protection System (FPS);

• Filtrex Filter Candles;

• Debris and Organism Collector (DOC); and

• Geiger’s Multi-Disc Screening System.

Currently, the Filtrex Filter Candles have not been tested and r esearch on the DOC was discontinued after limited laboratory testing. The original FPS has also not been tested. Howeve r, a variation of the original system that utilizes circular rotating screens with a fis h “scoop” has been installed at one facility and is currently being tested. Therefore, there is no new information to assess the feasibility, cost, or effectiveness of these three technologies at this time.

The multi-disc screens with fish protection features (for impi ngement) have been installed at two

facilities. The first installation was at the Potomac Ge nerating Station and was the subject of a one-year EPRI study. The preliminary results have been positive and it appears this technology has the potential to match the impingement mortality reduction results from Ristroph s creens. In addition, this technologyAn Addendum To The 316(B) Evaluation Of The Haynes Generating Station

2-2 provides the benefit of eliminating carryover. The second install ation was in late 2006 at the Salem Generating Station on the Delaware River and no data are available a t this time.

Another emerging technology with fish protection features, not av ailable in 2004, is a plastic belt screen manufactured by Hydrolox. These screens are lighter and potentia lly less costly to install and operate than other traveling screens. The plastic belt screens are new and do not have any long-term operational data, but pilot studies currently planned at one estuarine site on Long Island, NY should provide useful information on biological efficacy and operational issues. Becaus e of the material used and way that the screen is constructed, the smallest mesh size available at this time is 1.75 millimeters (mm). Thus, this technology has the same “limitation” as the Modular Inclined Sc reen (MIS) system in excluding only larger entrained organisms, and therefore, would not meet entrainment per formance standards for HnGS.

Two new currently available screening technologies (i.e., Hydrolox and Geiger screens) can be considered in the same category as Ristroph screens. Both of t hese systems function on the “trap and transfer” concept and require the same type of fish and debris returns as Ristroph screens. The modified traveling water screen discussions in Sections 3 and 4 apply to all three of t hese technologies.



### 2.3 I MPINGEMENT 

### M ORTALITY AND 

### E NTRAINMENT 

### C HARACTERIZATION

Although the relative contribution of the most abundant species impinged has varied from 1978/1979 to 2001/2002 to 2006, prominent species impinged include queenfish, topsmelt, norther n anchovy, shiner perch, white croaker, and specklefin midshipman. This most current impingement data do not change Alden’s selection of appropriate technologies for consideration at HnGS.

As expected, the entrainment data showed similar results. Gob ies, blennies, silversides, white croaker, and northern anchovy are key species entrained. In 2006, silversides and jacksmelt were also relatively

abundant. Of most interest were the results of the entrainment life history characterization. The 2006 results confirmed the 1978/1979 results and documented that 92-100% (dependi ng on species) of entrained organisms were “pre-transformation” stage. That is, the vast majority of entrained fish were less than 15 mm in length. The lengths of larvae collected in 2006 are provided in Table 2-2. This table replaces Table 2-8 in the initial evaluation.

These results do not alter Alden’s selection of appropriate te chnologies for consideration in reducing entrainment at HnGS. As discussed in Section 3, the overall effi cacy of any entrainment reduction technology is mitigated by the predominance of such early life history s tages.



### 2.4 C OSTS

Alden has revised and included in Section 5 of this Addendum Table 5-1 ( i.e., Table 6-3 from 2004 report) to reflect current (2006) costs of appropriate technologies. An adjust ment factor of 1.12 1 was used to account for inflation and the price per megawatt hour (MWh) w as increased from $40/MWh to $50/MWh 2 . For technologies that were evaluated further in this Addendum, the costs presented in Table 5-1 have been modified to reflect the updated evaluations.

1 Based on consumer price index from 2002 through 20 06.

2 Based on average annual day ahead prices for 2006 using SP-15 CAISO real time data.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

2-3 

### 2.5 S ECOND 

### C IRCUIT 

### C OURT 

### D ECISION

The Court issued its Decision on the Phase II Rule on January 27, 2007. T his Decision has significant impacts on the compliance alternatives and options discussed in t he 2004 Report. The major components

of the Decision are:

• The Court determined that two options, use of Restoration Measures and the Cost-Benefit Test, are unlawful and cannot be used for compliance;

• The Court remanded to the U.S. Environmental Protection Agency ( EPA) the determination of Best Technology Available (BTA); and

• The Court also remanded to EPA the Cost-Cost Test and Technology I nstallation and Operation Plan due to EPA’s failure to provide adequate opportunity for public review and comment for these two provisions.

The remand of the BTA determination introduces some uncertainty in the analysis, since the nature of the technologies and performance standards could change as a resul t of EPA revisions to the Rule. One of the key issues EPA is required to address is whether or not us e of wet or dry closed-cycle cooling is BTA.

The Court said EPA could consider three factors in this evalua tion. The first is cost, but only in a limited manner. To reject closed-cycle cooling from a cost standpoint, EP A must determine that the industry cannot reasonably bear the cost of a national retrofit with thes e technologies. The two other factors EPA may consider are adverse environmental impacts associated wit h closed-cycle cooling and impacts to energy production and efficiency.

A second major component of the Decision is a requirement to us e the “best performing” technology. The Court determined that if EPA chose to use performance standar d ranges, a facility’s decision could no longer be based on which technology was most cost-effective. Ra ther, the “best performing” technology in the appropriate performance standard range must be used. The Court did say that a less costly technology than the “best performing” technology could be use d if it works as least as well as the low end of the performance range of the “best performer.”

The result of the Decision is that HnGS will be limited to use of tec hnologies and/or operational measures for compliance. Use of the Cost-Cost Test may be available i f it is proposed for public review and comment. However, there is some risk that EPA could alter Appe ndix A costs and/or implementation provisions in the revised Rule.

As a result of the Decision, it will be important for LADW P to consider technologies from several perspectives:

• EPA could identify closed-cycle cooling as BTA: If this were to occur, it would be considered to be the “best performing” technology. Assuming this were the case, it is wor th noting that EPA, in the Rule, stated that closed-cycle cooling was capable of ac hieving a 70 to 96% reduction in flow in salt water when make-up and blowdown flows are minimized. The lower end of the range was driven by states where water quality standards limited chloride to a maximum of 10% over background and therefore required a 1.1 cycle-of-concentration. It will be important to determine

the level of flow reduction achievable in California. What ever level of flow reduction could be achieved at HnGS with closed-cycle cooling would establish the per formance standard. For example, it could be determined that salt water cooling towers at HnGS coul d achieve a 90% flow reduction (i.e. entrainment reduction). If this were the case, t hen a 90% reduction would become the HnGS performance standard. Alternative fish protection technol ogies and/or operational measures could be employed; as long as they achieved the same 90% reduction as closed-cycleAn Addendum To The 316(B) Evaluation Of The Haynes Generating Station

2-4 cooling. Closed-cycle cooling is discussed qualitatively in Section s 2.4 and 3.4 of this

Addendum.

• EPA could determine that closed-cycle cooling is not BTA or does not pass a re-proposed CostCost Test: In either case, the new driver for technology s election will be based on a determination of which technology is “best performing.”

• EPA could revise the schedule: If EPA engages in a rulemaking, it is antic ipated that the January, 2008 deadline for submittal of the Comprehensive Demonstration Study (C DS) will be suspended. EPA did not budget for a major 316(b) rulemaking in 2007, so it is not clear when a

revised Phase II Rule would become effective. The result is un certainty as to when compliance will be required. Due to this uncertainty, EPA may revert to i ssuing §316(b) requirements on “Best Professional Judgement” (BPJ). This was the approach E PA used prior to promulgation of the Phase II Rule. Given California’s advocacy on 316(b) issues, thi s potential has little effect on LADWP’s facilities. The suspension of the schedule would allow addition al time to conduct pilot studies to identify the “best performing” technology for HnGS.

Another regulatory uncertainty for the Rule is anticipated guidance on whether or not the Rule is based on design or actual flow. This guidance has been promised for several years, but ha s yet to be provided. The flow is an important consideration for Units 1 and 2, which operate less freque ntly than the other units.

As in 2004, fish protection technologies were considered to have potential for application at HnGS if:

• The technology has proven biological effectiveness;

• The technology is available and does not require further engineering development; and

• The technology has engineering and/or biological advantages over t he other technologies we

evaluated.

Table 2-3 is a revision to Table 3-1 from the initial evaluation.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

2-5 T ABLE 2-1. P ERTINENT P ROJECT D ATA (R EVISED T ABLE 2-1 FROM THE I NITIAL R EPORT )

Location Long Beach, California (HnGS)

Latitude: N 33 o 45’ 05’’ Longitude: W118 o 06’ 15’’ Waterbody: Pacific Ocean

NPDES permit expiration date: May 10, 2005

Estimated project intake flow

Plant design: 1,497 cfs (672,000 gpm) Units 1&2: 213.8 cfs (96,000 gpm) each Units 5,6&8: 356.5 cfs (160,000 gpm) each Intake velocities (mean lower low water)

Horizontal current at trash rack: 1.4 feet/sec Intake conduit design velocity: 5.2 feet/sec Intake conduit calculated velocity: 5.0 feet/sec Intake channel velocity: 1.3 feet/sec Mean velocities upstream of screens: Units 1&2 (stationary screens): 0.9 feet/sec Units 5&6 ( traveling screens): 0.7 feet/sec Unit 8 (traveling screens): 0.6 feet/sec

Water Level
Elevations
Extreme low: El. -6.0 feet

Mean lower low water: El. -2.7 feet Extreme high: El. 3.0 feet Water depths: (around intake)

Maximum: approx 12.0 feet Minimum: approx 9.5 Normal: approx 10.0 feet
Other info: all elevations refer to mean sea level Project Structures

Intake structure:

Type: onshore intake Location: Long Beach Marina Intake openings: 7 Top of intake opening: El. -2.0 feet Bottom of intake opening: El. -9.5 feet Intake opening width: 50 feet Intake barrier: bars centered 6 in apart Conduit pipes: 7 Conduit pipe length: approx. 1,100 feet Conduit pipe diameter: 8 feet (inside diameter) Conduit pipe invert: El. -14.4 feet
Intake channel structure

Channel invert: El. -19.0 feet
Banks: El. 8.0 feet Length: approx. 1.5 mi Design velocity: 1.0 feet/sec Calculated velocity: 1.3 feet/sec (mean lower low wate r)An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

2-6 Stationary Screens (Units 1&2)

Location: along intake channel Sections: 4 (2 per unit, 10.0 feet wide, 21.7 feet ta ll)
Invert: El. -15.0 feet Top: El. 6.7 feet
Mesh size: 3/8 in Traveling water screens (Units 5, 6 & 8)

Location: along intake channel Number: 12 (4 per unit)
Unit 8:
Screen width: 10.9 feet
Invert: El. -16.0 feet Top: El 6.7 feet Rotation speeds: 1.4 rpm
Units 5&6:
Screen width: 9.0 feet
Invert: El. -17.0 feet Top: El 6.7 feet Rotation speeds: 1.54 rpm
Mesh size: 3/8in Spray wash volume per screen: 400 gpm Spray wash Operation: once per shift Trough configuration: two troughs leading to trash bo xes Circulating water pumps

Number of pumps: 12 (2 per intake) Type of pumps: vertical, single-staged
Inlet elevation: -16.0 feet Flow per pump: Units 1-2: 107 cfs (48,000 gpm) Units 5 & 6: 178.2 cfs (80,000 gpm) Unit 8: 89.1 cfs (40,000 gpm)
Total flow Condensers: 1497 cfs (672,000 gpm) Cooling water discharge

Location: San Gabriel River Depth: 21.3 feet Discharge pipe: 6 conduit pipes Type: 3 discharge structures (one for each Unit pair)

Power Generation Fuel Type: Units 1,2, 5, 6 & 8: gas/oil

Plant output: (rated) Units 1&2: 222 megawatts (MW) (each)
Unit 5: 341 MW
Unit 6: 259 MW
Unit 8: 235 MW Units 9&10: 170 MW (each) Total rated capacity: 1,619 MW Plant capacity factor (2000-2004) (No generation data for Unit 8 provided)

Unit 1: 30%An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

2-7 Unit 2: 34%
Unit 5: 26%
Unit 6: 17% Average annual energy: 2,414,940 MWh (2000-2004)(Un its 1, 2, 5 and 6)An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

2-8 T ABLE 2-2. R EVISED T ABLE 2-3 FROM THE I NITIAL E VALUATION

– C OMPARISON OF P ERCENT

C OMPOSITION OF E NTRAINED L ARVAE L ENGTHS C OLLECTED AT H N GS

Percent Composition *

Species 2006 Study

% of Total
Entrainment 0-5mm 5-10mm 10-15mm >15mm

anchovy <1% 19% / 86% 28% / 12% 33% / 1% 20% / --
gobies 50% 86% / 97% 7% / 2% 7% / 1% <1% / --
blenny 19% 100 %/ 100% <1% / <1% -- / -- -- / --

white
croaker 2% 97% / 40% 2% / 60% 1 / -- -- / --

queenfish <1% 89% / 38% 11% / 62% -- /-- -- / --

References: Intersea Research Corporation (IRG), Haynes Generating Station Cooling Water Intake Stud y 316(b) Demonstration Program 1978-1979. (1981) Tenera Environmental, IM&E Characterization Study Preliminary Results 2006 , unpublished. (2007)

* 1981 data / 2006 dataAn Addendum To The 316(B) Evaluation Of The Haynes Generating Station2-9TABLE2-3.INITIALSCREENING OFFISHPROTECTIONALTERNATIVES ATHNGS(REVISEDTABLE3-1FROM THEINITIALEVALUATION)ConceptBiologicalEffectivenessProvenEngineeringAlternativeAvailableAdvantagesover OtherConceptsPotential forApplicationat HNGSCommentsBehavioral BarriersSound yes yes no no The focus of recent fish protection studiesinvolving underwater sound technologies hasbeen on the use of new types of low and highfrequency acoustic systems that have notpreviously been available for commercial use.Sound devices are not appropriate forentrainment reduction as the early life stageshave not yet developed hearing capabilities orhave insufficient swimming capability to avoidentrainment.Infrasound no yes yes no There was a general beliefin the scientificcommunity that infrasound could represent aneffective fish repellent since there was aphysiological basis for understanding theresponse of fish to particle motion. Sounddevices are not appropriate for entrainmentreduction as the early life stages have not yetdeveloped hearing capabilities or haveinsufficient swimming capability to avoidentrainment.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station2-10TABLE2-3.INITIALSCREENING OFFISHPROTECTIONALTERNATIVES ATHNGS(REVISEDTABLE3-1FROM THEINITIALEVALUATION)ConceptBiologicalEffectivenessProvenEngineeringAlternativeAvailableAdvantagesover OtherConceptsPotential forApplicationat HNGSCommentsStrobe lights yes yes no no Although many studies have evaluated strobelights as a primary barrier system, strobes areoften evaluated as part of an integrated fishprotection and passage system that includesother devices such as screens, narrow-spacedbar racks, bypasses, and/or other behavioralsystems. As a secondary system, strobe lightshave the potential to incrementally increase fishprotection effectiveness. However, they are noteffective with larval fish that have little or nomotility.Mercury lights no yes yes no Response to mercury light has been shown tobe species-specific; some fish species areattracted, others repelled, and others havedemonstrated no obvious response. However,they are not effective with larval fish that havelittle or no motility.Chemicals no no no no Use of chemicals has been suggested, and insome cases evaluated, as fish protectionmeasures. However, no practical application ofthese devices has been developed, and they arenot considered available technologies forapplication at CWISs.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station2-11TABLE2-3.INITIALSCREENING OFFISHPROTECTIONALTERNATIVES ATHNGS(REVISEDTABLE3-1FROM THEINITIALEVALUATION)ConceptBiologicalEffectivenessProvenEngineeringAlternativeAvailableAdvantagesover OtherConceptsPotential forApplicationat HNGSCommentsElectric screens no yes no no Electric barriers have been shown to effectivelyprevent the upstream passage of fish. However,attempts to divert or deter the downstreammovement of fish have met with limited success.Consequently, past evaluations have not led topermanent applications. The potentialeffectiveness of these barriers for application atCWISs is unknown. Given their pastineffectiveness and hazard potential, electricscreens are not considered a viable technologyfor application at CWISs. As with otherbehavioral barriers, electric barriers would not beeffective with larval fish that have little or nomotility.Air bubble curtain yes yes no no These curtains generally have been ineffectivein blocking or diverting fish in a variety of fieldapplications. Air bubble curtains have beenevaluated at number of sites on the Great Lakeswith a variety of species. All air bubble curtainsat these sites have been removed from service.Air bubble curtains would not be effective withlarval fish that have little or no motility.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station2-12TABLE2-3.INITIALSCREENING OFFISHPROTECTIONALTERNATIVES ATHNGS(REVISEDTABLE3-1FROM THEINITIALEVALUATION)ConceptBiologicalEffectivenessProvenEngineeringAlternativeAvailableAdvantagesover OtherConceptsPotential forApplicationat HNGSCommentsWater jet curtain no yes no no Devices such as water jet curtains have beensuggested, and in some cases evaluated, as fishprotection measures. However, no practicalapplication of these devices has beendeveloped, and they are not consideredavailable technologies for application at CWISs.Hanging chains no yes no no Devices such as hangingchains have beensuggested, and in some cases evaluated, as fishprotection measures. However, no practicalapplication of these devices has beendeveloped, and they are not consideredavailable technologies for application at CWISs.In addition, they are not effective with larval fishthat have little or no motility.Visual keys no yes no no Visual cues have been suggested, and in somecases evaluated, as fish protection measures.However, no practical application of thesedevices has been developed, and they are notconsidered available technologies for applicationat CWISs.Hybrid barriers (e.g.,strobe light /air bubblecurtain)no no no no No practical application of these devices hasbeen developed, and they are not consideredavailable technologies for application at CWISs.In addition, they are not effective with larval fishthat have little or no motility.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station2-13TABLE2-3.INITIALSCREENING OFFISHPROTECTIONALTERNATIVES ATHNGS(REVISEDTABLE3-1FROM THEINITIALEVALUATION)ConceptBiologicalEffectivenessProvenEngineeringAlternativeAvailableAdvantagesover OtherConceptsPotential forApplicationat HNGSCommentsPhysical BarriersFixed screens yes yes no no As a barrier device, afixed screen can only beeffective if there is a low through-screen velocityand a way for fish to escape the CWIS. Finemesh devices would be required for entrainmentreduction. These early life history stages havelimited motility which further reduces thepotential for protection for this technology.Conventional travelingwater screensyes yes no no As barrier devices, traveling screenscannot beconsidered for protection of early life stages oraquatic organisms that have little or no motility.Rotary drum screens yes yes no no Installation of rotary drum screens would requirea much larger area than conventional travelingscreens because of the lower design velocity.Barrier net yes yes no no Barrier nets can be considered a viable optionfor protecting adult fish provided that relativelylow velocities (generally less than 1 feet/sec)can be achieved and debris loading is light.They would be ineffective with early life historystages that have little or no motilityAn Addendum To The 316(B) Evaluation Of The Haynes Generating Station2-14TABLE2-3.INITIALSCREENING OFFISHPROTECTIONALTERNATIVES ATHNGS(REVISEDTABLE3-1FROM THEINITIALEVALUATION)ConceptBiologicalEffectivenessProvenEngineeringAlternativeAvailableAdvantagesover OtherConceptsPotential forApplicationat HNGSCommentsBar rack barrier yes yes no no Bar rack barriers are typically designed to havespacing greater than 1 inch and would noteffectively prevent the entrainment of early lifestages. They may, however, effectively reduceimpingement.Infiltration intakes yes yes no no Radial wells andartificial filter beds have beensuccessfully used to supply small quantities ofwater. While such systems have little if anybiological impact, they have not been developedfor screening large flow volumes or for CWISapplication.Porous dike yes yes no no Rock structures such as rock cribs and porousdikes allow water to pass while preventingpassage of juvenile and adult fish. Theireffectiveness with larval fish is unknown.Aquatic filter barrier(AFB)yes yes no no At this time, the AFB system is considered to beexperimental despite its potential biologicaleffectiveness. In addition, the space required forinstallation of this technology is not available atHnGS.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station2-15TABLE2-3.INITIALSCREENING OFFISHPROTECTIONALTERNATIVES ATHNGS(REVISEDTABLE3-1FROM THEINITIALEVALUATION)ConceptBiologicalEffectivenessProvenEngineeringAlternativeAvailableAdvantagesover OtherConceptsPotential forApplicationat HNGSCommentsCylindrical wedgewirescreen intakesyes yes no no Wedgewire screens have the potentialto reduceboth entrainment and impingement at waterintakes. Effectiveness is based on the slot size,through-slot velocity, and presence of anambient cross-current to carry organisms anddebris away.Collection SystemsModified traveling(Ristroph-type)screens (coarse- andfine-mesh) with fishprotection featuresyes yes yes yesModified traveling water screens continue to bean available technology that can reduce fishlosses due to impingement and entrainment.The primary concern with fine-mesh screens isthat they function by impinging early organismlife stages that are entrained through coarsemesh screens. Depending on species and lifestage, mortality from impingement can exceedentrainment mortality. Biofouling potential mustalso be considered.Fish pumps yes yes no no Hidrostal and Archimedes screw pumps havedemonstrated an ability to transfer adult fish withlittle or no mortality. These pumps bythemselves do not represent a technology forprotecting fish. However, when coupled with fishbypass systems such as angled screens andlouvers, fish pumps are biologically effective.The effect of the pumps on larval fish wouldneed to be evaluated.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station2-16TABLE2-3.INITIALSCREENING OFFISHPROTECTIONALTERNATIVES ATHNGS(REVISEDTABLE3-1FROM THEINITIALEVALUATION)ConceptBiologicalEffectivenessProvenEngineeringAlternativeAvailableAdvantagesover OtherConceptsPotential forApplicationat HNGSCommentsDiversion SystemsLouvers / angled barracksyes yes no no Due to the large spacing of the louver slats,louver systems do not protect early life stages offish.Angled screens (fixedor traveling)yes yes no no Angled screens can be considered a viableoption for protecting juvenile and adult lifestages provided that proper hydraulic conditionscan be maintained and debris can be effectivelyremoved. Fish eggs, larvae, and smallinvertebrates would not be protected by angledscreens unless fine-mesh screening was used.Also, as the length of screen increases thesurvival of larvae decreases. Guidanceefficiency improves as fish grow.Angled rotary drumscreensyes yes no no Installation of angled rotary drum screens wouldrequire an even larger area than “conventional”rotary drum screens.Inclined plane screens no yes no no No advantage over MIS at HnGS.Eicher screen yes yes no no While biologically effective, the Eicher screenwas designed for penstock and pipes. There isno advantage over an MIS at HnGS.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station2-17TABLE2-3.INITIALSCREENING OFFISHPROTECTIONALTERNATIVES ATHNGS(REVISEDTABLE3-1FROM THEINITIALEVALUATION)ConceptBiologicalEffectivenessProvenEngineeringAlternativeAvailableAdvantagesover OtherConceptsPotential forApplicationat HNGSCommentsModular inclinedscreens (MIS)yes yes yes yesThe combined results of laboratory and fieldevaluations of the MIS have demonstrated thatthis screen is an effective fish diversion devicethat has the potential for protecting fish at waterintakes. Any consideration of the MIS for CWISapplication should be based on future largescale, prototype evaluations. Some reduction inentrainment can be expected.Submerged travelingscreensno yes no no Designed for partial screening of hydroelectricproject intakes. Not applicable to HnGS.Modifications to Reduce Intake FlowModified pumpoperationyes yes yes yesReducing flow will reduce impingement andentrainment. Flow reduction could beaccomplished by either turning pumps on and offor with the installation of variable speed drives tofollow the load (see below). If HnGS isoperating at or near its thermal effluent limitsthen units would need to be de-rated during flowreduction.Install variable speeddrives (VSD)yesyes yes yesVariable speed drives could be used at HnGS tobetter regulate intake flow. Variable speeddrives would allow HnGS to minimize lostgeneration during peak periods.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station2-18TABLE2-3.INITIALSCREENING OFFISHPROTECTIONALTERNATIVES ATHNGS(REVISEDTABLE3-1FROM THEINITIALEVALUATION)ConceptBiologicalEffectivenessProvenEngineeringAlternativeAvailableAdvantagesover OtherConceptsPotential forApplicationat HNGSCommentsInstall closed-cyclecooling system(mechanical, naturaldraft and dry coolingtowers)yes yes yes yesClosed-cycle cooling will reduce flowsignificantly. Depending on the type of closedcycle system installed and the maximum numberof cycles-of-concentration, circulating water flowin salt water could be reduced 73-98%.Impingement and entrainment would be reducedaccordingly.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

3-1 

## 3.0 ENTRAINMENT REDUCTION OPTIONS

As stated previously, compliance with EPA’s entrainment reduc tion performance standards will be difficult for marine facilities. Closed-cycle cooling or dra matic reductions in cooling water flow by limiting station operations are extreme and costly measures. There are limited technologies that can be considered for reducing entrainment and even more limited informat ion of the efficacy of these technologies with marine or estuarine species.

Fine-mesh traveling screens (e.g. Ristroph-type, Hydrolox, or Geige r) have potential for application at HnGS. There are currently no additional data available on the ef fectiveness of these screens in reducing mortality of entrainable organisms.

The MIS concept is a fish diversion system that guides fish in to a bypass at high velocities and was previously considered for impingement mortality reduction. The MI S would reduce entrainment of larger organisms as well as impingement. There are currently no data available on the effectiveness of these screens in reducing mortality of the early life history sta ges of the entrainable organisms for the species

present.



### 3.1 F INE



### - MESH 

### M ODIFIED 

### T RAVELING 

### S CREENS

Alden’s original evaluation reflected several issues relati ve to this technology that existed in 2004. First, the approach velocity to the existing traveling screens exceeds the typical design velocity for this technology (i.e., 0.5 feet/sec); existing approach velocities ar e 0.9 feet/sec at Units 1 and 2, 0.7 feet/sec at Units 5 and 6, and 0.6 feet/sec at Unit 8. As such, Alden provided co sts based on an expanded

screenhouse that would accommodate the additional screens needed to reduce the approach velocity. Such an expansion would require extensive site work and lengthy unit down time.

Having reviewed the 2006 entrainment characterization study resul ts for HnGS, Alden now believes that survival of the earliest life history stages of fish ent rained at HnGS will be negligible. These life stages dominate the entrainment numbers and, therefore, this technology would proba bly not meet the entrainment reduction standard. For consistency, costs for the expanded i ntake option have been provided in this Addendum. However, Alden recommends that pilot studies be conducted if LADWP wants to consider this technology further. The pilot study proposed for LADW P’s Harbor Generating Station (which has lower velocities that HnGS) would identify where surv ival of previously entrained organisms

starts to occur.

LADWP has requested a prediction of the size mesh required to e ffectively exclude larval fish at HnGS. The key factor in exclusion of aquatic organisms is the maximum dimension of the organism. Typically, head capsule depth (HCD) is selected as it is the earliest -developed, non-compressible body part. Unfortunately, Alden could not find adequate data on the West Coast spe cies of interest at HnGS to develop the necessary analyses. However, adequate data have bee n developed for East Coast species. Based on discussions between Alden and MBC staff, the following surr ogates were used for this

assessment:

West Coast Species Length at hatch (mm) East Coast Species Predicted HCD (mm)

Gobiidae 2.7-3.2 Naked goby 0.56
Hypsoblennius 2.0 Atlantic menhaden 0.83

Silversides 3.8-5.0 Atlantic silversides 0.44
White croaker 2.2-2.8 Bay anchovy 0.37An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

3-2 West Coast Species Length at hatch (mm) East Coast Species Predicted HCD (mm)

Jacksmelt 7.5-8.6 Bay anchovy 0.74
Topsmelt 4.3-4.9 Bay anchovy 0.50
Grunion 6.5-6.7 Bay anchovy 0.67
Northern anchovy 2.5-3.0 Bay anchovy 0.34

The data used for this assessment are provided in Attachment D. Based on the above information, a nominal mesh size of 0.3 mm would be required to exclude northern anchovy yol k-sac larvae. However,

to be conservative a 0.2 mm mesh screen was selected to exclude larvae found at HnGS. Based on information provided by screen manufacturers, a screen with a me sh/slot size of 0.2 mm can be provided. Engineering data on the various meshes are provided in Attachm ent A. The following design considerations are associated with the replacement of the exi sting 9.5 mm mesh screens with 0.2 mm

screens:

• Increase head loss – Head loss will increase from 0.2 to 5 inches in a clean condition, and 2 to 24

inches at 50% blocked with debris.

• Screen rotation speed – Screens should be designed to operate co ntinuously with a high rotation speed to remove debris quickly. The debris loading will incr ease from current conditions due to the smaller opening.

• Screen mesh – A 0.2 mm screen mesh will require a 1-inch backup m esh for added strength. The wire diameter of a 0.2 mm square mesh screen is only 0.2 mm and c ould easily be damaged by large debris. More frequent screen replacement is expected.

• Pre-screening – Pre-screening devices are recommended to reduc e potential damage and to reduce the debris loading at the screens. A fine-bar rack or bar screen with a 1⁄2- to 1 -inch spacing and/or a 3/8-inch traveling water screen may be required upstre am of the fine-mesh screen

installation.

The location of the existing traveling screens presents another iss ue. Impinged and entrainable organisms collected from the screens will have to be transported a consi derable distance to a safe release point. In addition, fish and shellfish species and their associated life s tages tend to vary considerably in terms of their ability to tolerate the collection and handling associa ted with this option, which emphasizes the need for species and life stage specific testing to verify sur vival rates. As stated previously, Alden believes that there are methods for maintaining a clean fish return system. A review and comparison of two potential fish return cleaning systems is provided in Attachment E.

Finally, concern has been expressed with biofouling of the exposed (abov e water surface) screening components during continuous operation of the screen. Although this may be a valid concern, an assessment could easily be performed during a pilot study. Developme nt of a fouling control technology could be a component of the pilot study. However, rather than confound the bi ological assessment component of the study, it may be desirable to conduct a small-scale , focused study for evaluating biofouling conditions. Costs for this component of a pilot study have not been develope d.

Conclusion

Fine-mesh traveling screens are technically an “exclusion te chnology.” However, unlike narrow-slot, wedgewire screens that depend on an air-burst cleaning system coupled with ambient currents to “carry” impinged fish and debris away from the CWIS, this technology utilizes a “trap and t ransfer” concept. The process of collecting organisms to assess survival imparts som e level of mortality that is difficult to ascertain in the field. Consequently, the projected efficacy of this technology will be less than that forAn Addendum To The 316(B) Evaluation Of The Haynes Generating Station

3-3 narrow-slot, wedgewire screens. The life stages that dominate the entrai nment numbers at HnGS are such that this technology would probably not meet the entrainment reduction standard.



### 3.2 M ODULAR 

### I NCLINED 

### S CREENS

Originally, the MIS was proposed as a technology to reduce impingeme nt mortality by virtue of a 2 mm slot size (the only size for which data are available). H owever, in reconsidering entrainment reduction alternatives, Alden proposed consideration of the MIS for reducing larger entrainable organisms. Results of species-specific survival from pilot studies of both the fi ne-mesh traveling screens and the MIS could be compared to develop overall efficacy.

All the ancillary issues associated with traveling water screens ( e.g., handling and long-distance transport) apply to MIS. The one exception would be elimination of the conc ern with above- water biofouling as the system is submerged. The current heat treatment practice s used with the existing screens (that would be effective, for underwater biofouling of the traveling scree ns) would have to be relocated to be applicable here. If the MIS proved effective, and biofouling issue s were documented during the pilot tests, a heat treatment alternative could be considered.

Conclusion

As with the fine-mesh screen alternative, the projected effi cacy of this technology will be less than that for narrow-slot, wedgewire screens. However, depending on the ult imate efficacy for the fine-mesh screens, this alternative may be as effective as the othe r fine-mesh screen options. Alden does not believe

the MIS will meet the entrainment reduction standard. The resu lts of the pilot study will remove this uncertainty. The ultimate cost of the systems would dictate the technolog y selection.



### 3.3 F LOW 

### R EDUCTION

The potential use of this option is contingent upon the diel and seasonal densities of entrainable life stages when operation of cooling water pumps could be reduced. The results of t he seasonal and diel variations for entrained organisms from the 2006 IM&E studies are not availa ble at this time. If results from the 1978/1979 studies hold true, there are no substantial day/night diffe rences and entrainment is not

concentrated on a seasonal basis. This would eliminate the abili ty to target flow reductions during periods of high entrainment. Tenera and MBC are in the process of completing the entrainment study sample processing and results should be available for generation analys is in the second quarter of 2007.

There are two approaches that could be used to reduce cooling water fl ow. The first is strictly operational by curtailing use of one or more existing pumps on a diel or seasonal basis; the second would be to retrofit pumps with variable speed drives (VSDs). The VSDs would allow much finer control of flow reductions while ensuring adequate flow to meet heat rate and gener ation needs. Also, the question of whether design or actual flow can be used for the calculati on baseline needs to be considered. If the calculation baseline is based on design flow this option could be es pecially attractive for Units 1 and 2. Under design flow it is assumed that all pumps for all of HnGS Units operate 24 hours/day, 365 days / year. As pointed out in the Proposal for Information Collection (P IC), the HnGS Units have capacity factors that have averaged approximately 16% (Unit 6) to 30% (Unit 2) between 1999 and 2005. Generally, there is some correlation between capacity utiliz ation and pump operation, since it does not make sense incur the cost of operating the cooling water pumps when electricity is not being generated. Facility staff stated this to be the case for HnGS during the site visit. Thus using the design flow assumption, HnGS could take credit for the flow reduction when the cooling water pumps normally do not operate. Due to relatively low capacity utilization, this could generate a significant entrainment reduction credit at very little cost since no energy penalty w ould be required. The only concern would be that if there is a significant increase in capacity utiliza tion for these Units in the future, additionalAn Addendum To The 316(B) Evaluation Of The Haynes Generating Station

3-4 entrainment reduction actions could be required. However, under act ual flow, flow reduction credits can only be taken by reducing flow from current operations. Regardless, i t is unlikely that flow could be reduced sufficiently to meet the current performance standard range.

If LADWP were to install VSDs on the circulating water pum ps, a detailed, design review of condensers, circulating water pumps, motors, and piping would need to be conducted to ide ntify potential issues associated with VSDs. Some key operational issues that would ne ed to be addressed are: unbalanced pump operation if a VSD is placed on only one pump per unit, loss of pre ssure in the condenser waterboxes, vibration of the pumps at lower speeds, and potential to bu rn out the existing motors. This review will further identify the limitations that may exi st and provide recommendations for each unit upgrade. The cost to install VSDs on all the circulating wate r pumps is included in the cost section. The following upgrades are not included in our cost estimate; but would be require d prior to installing VSDs:

1. Installation of a back-pressure valve on the condenser discharge;

2. Installation of pump discharge valves;

3. New circulating water pumps; and

4. New pump motors.

Conclusion

Consideration of flow reduction remains a possible alternative . Typically, flow reductions need to be discussed with Corporate Power Supply. Assessment of general trends in load demand can predict periods where running at reduced loads or placing a unit(s) on sta ndby would not affect reliability of the plant. These flow reductions would result in some flow reducti on credit. During periods of high demand and high water temperatures, reducing flow may result in the need to de-rate the unit(s) to maintain thermal discharge limits. Use of VSDs could be considered t o better control flow reductions and minimize lost generation. Costs have been included in this Addendum . Regardless, this option by itself would not likely meet the entrainment reduction standard.



### 3.4 C LOSED



### - CYCLE 

### C OOLING

Closed-cycle cooling was assessed on a cursory level in the 2004 re port. LADWP is participating in the closed-cycle cooling retrofit cost evaluation study. The result s of this evaluation will identify the economic penalties associated with this option. It is also impor tant to consider several options for use of closed-cycle cooling. There is the potential that when conside ring revisions to the Rule EPA could determine that use of wet or dry closed-cycle cooling is BTA. There are sig nificant arguments to be made that the cost of a national retrofit cannot be borne by industry. H owever, if EPA identified closed-cycle cooling as BTA, it would be considered the “best performing” tec hnology. Under this scenario, the CostCost test (after re-proposal for review and comment) could stil l determine that closed-cycle cooling has a cost significantly greater than the cost estimated by EPA.

Finally, should LADWP move forward with re-powering of Units 5 and 6, use of closed-cycle cooling should be considered as part of the project. This would provide not only an overall facil ity flow reduction credit, but provide a benefit in addressing the thermal loadi ng concerns in the San Gabriel River. Time

constraints do not allow for an effective assessment of the var ious options to be considered for the repowering.

Conclusion

Closed-cycle cooling will meet all performance standards, but whe ther or not closed-cycle cooling will be required to meet the standard is not know at this time. Cooling towers would have the highest overallAn Addendum To The 316(B) Evaluation Of The Haynes Generating Station

3-5 capital and operating & maintenance (O&M) cost of all of the alternatives. However, as part of repowering Units 5 and 6, closed-cycle cooling may be a cost-effective alterna tive.



### 3.5 A DDITIONAL 

### T ECHNOLOGIES

During discussions, an alternative of using narrow-slot, wedgewire s creens in the station “forebay/end-ofcanal” in conjunction with fish-friendly bypass pumps was suggest ed. To function effectively, a wedgewire screen system requires an “ambient” flow to remov e impinged fish and debris; the bypass pumps would provide this flow. The following discussion relates to e xisting conditions and does not take into account the Units 5 and 6 re-powering potentials.

Alden has considered this option under the current HnGS operations. A total of 56, T-84 narrow-slot (0.5 mm) wedgewire screens would be needed. A narrower slot size was not considered as 0.5 mm is currently the smallest slot size available for cylindrical screens. A 0.2 mm slot wedgewire screen can be provided; however, the number of screens required is substantial (i.e., a pproximately 120 for HnGS). The vendor also questions whether the air-burst backwash system would functi on effectively since it is anticipated that macrofouling would be more of an issue with narrower slot size.

Due to the number and size of the screens required to assure the 0. 5 feet/sec through-slot velocity, the screens would need to be mounted to a long, bulkhead wall that would i solate the flow through the

screens from the flow down the canal. This bulkhead wall would reduc e the cross-sectional area of the intake canal by approximately 25% near the screens.

To provide a sweeping flow, bypass pumps would be added at the terminus of the canal. A sweeping flow of 1.0 feet per sec (ft/s) is considered adequate to assur e removal of backwashed fish and debris for this configuration. The bypass flow would be approximately 700 cubic f eet per second (cfs), which could be provided with several fish-friendly pumps located in a new pumphouse at the terminus of the intake canal. The actual bypass flow required would be dependent on the fi nal layout of the screens and the expected unit operations. Biofouling could be minimized by using scr eens made of Z-alloy, an antibiofouling nickel-copper alloy. The discharge of the bypass pumps (re turn pipes) would be subject to the same biofouling concerns associated with other technologies. I f LADWP were to entertain this option, Alden would strongly recommend conducting hydraulic or physical modeling of this option for which costs are not included. A conceptual design and cost estimate of th is wedgewire screen configuration in the canal with a bypass pump system are provided in Attachment F.

During the conference call on January 30, 2007, another option of a n angled, flat-panel wedgewire screen with a bypass pump was also suggested. Assuming an average depth of 10 feet (in Long Beach Marina) and a through-slot velocity of 0.5 ft/s, a screen with a 0.5 mm slot ope ning with 50% porosity placed perpendicular to the flow would be 600 feet in length. If the porosity were 30% the lengt h would increase to 1,000 feet. However, to provide guidance to the bypass pump, the screen would have t o be placed at an angle to the intake flow. A screen with 50% porosity angled a t 45o or 30o to the flow would be 840 and 1,200 feet long, respectively. At 30% porosity, the lengths would incr ease to 1,400 and 2,000 feet, respectively. An installation of this magnitude is clearly impractical for consideration in Long Beach

Marina. If this installation were considered within the intake c anal, the length of the screens would be cut roughly in half (assuming a 20-foot canal depth). Larval fish and entra inable sized organisms do not have the sustained swimming speeds necessary to effectively respond to this type of technology. Therefore, this option has not been considered further.

Alternatively, if the Gunderboom “Marine Life Exclusion System ” (MLES) were to be considered in the intake canal, an MLES 4,700 feet in length would be required at a 45o angle to the flow; at a 30o to the flow, the MLES would be 6,700 feet long. A cost estimate for this option has not been de veloped.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

3-6 Finally, there was discussion of the potential to tunnel offshore to i nstall cylindrical wedgewire screens. Alden estimates that at a minimum a two-mile-long tunnel would be required. This tunnel would have the same biofouling problems currently experienced at all Calif ornia facilities with offshore intakes. In addition, the distance would not allow use of the air-burst backwas h system. A conceptual design and a cost estimate have not been developed for this option.

Conclusion

Either variation of the wedgewire technology or MLES that re quires use of a bypass pump would certainly be questioned as to the efficiency of “moving” fish and debris removed f rom the system(s) to the bypass pump and the effect of the pump passage on survival. The onl y available guidance/survival data with West Coast species indicate that guidance efficiency a nd survival improve as fish grow. However, survival of fish <20 mm is poor (LMS 1981). In addition, the organis ms would have to be returned to a safe point of discharge, which further confounds a valid assessme nt of efficacy. Alden does not believe this approach could be proven to be effective in meeting the entr ainment reduction performance standard. It is also Alden’s belief that an intake “extension” proj ect to consider wedgewire screens at an offshore location would not be practicable.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

4-1 

## 4.0 IMPINGEMENT MORTALITY REDUCTION OPTIONS

As stated previously, technologies considered for compliance wit h EPA’s entrainment reduction performance standards would also be applicable for the impingeme nt mortality reduction standards. The previous concerns expressed for closed-cycle cooling or dramati c reductions in cooling water flow to reduce entrainment are also valid when considering impingement. The following addresses these technologies with consideration of updated information developed since 2004.



### 4.1 C OARSE



### - MESH 

### M ODIFIED 

### T RAVELING 

### S CREENS

The velocities approaching the existing traveling water sc reens are 0.9 ft/s at Units 1 and 2; 0.7 ft/s at Units 5 and 6, and 0.6 ft/s at Unit 8. These velocities are within the range of velocities that provide good survival for most impinged species with traveling screens that been modified for fish protection (Ristroph screens in Alden’s original report). Limited survival data exist for species impinged at HnGS. Therefore, Alden still recommends conducting pilot studies before full-scal e installation. If a pilot-scale study to document impingement survival rates was conducted at LADWP’s Ha rbor Generating Station (which has lower velocities than HnGS), the results would also apply to survival of impinged organisms at HnGS.

The location of the existing traveling screens presents another issue. Impinged organisms collected from the screens will have to be transported a considerable distance to a safe release point. In addition, fish and shellfish species and their associated lifestages tend to v ary considerably in terms of their ability to tolerate the collection and handling associated with this option, whi ch emphasizes the need for species and life-stage-specific testing to verify survival rates. As stated previously, Alden believes that methods exist for maintaining a clean fish return system. Two potential options ar e summarized in Attachment C.

Finally, concern has been expressed with biofouling of the exposed (abov e water surface) screening components during continuous operation of the screen. Although this m ay be a valid concern, assessment could easily be performed during a pilot study. Development of a fou ling control technology could be a component of the pilot study. However, rather than confound the bi ological assessment component of the study, it may be desirable to conduct a small-scale, focused stu dy for evaluating biofouling conditions. Costs for this component of a pilot study have not been developed.

Conclusion

Coarse-mesh modified traveling screens are still a viable a lternative for impingement mortality reduction. The ability to meet the impingement mortality performance stand ard would depend on the species present and Alden is uncertain if this standard could be met with the species prese nt at HnGS.



### 4.2 M ODULAR 

### I NCLINED 

### S CREENS

Originally, the MIS was proposed as a technology to reduce impingeme nt mortality by virtue of a 2 mm slot size (the only size for which data are available) and is still a vi able option. If the proposed pilot study is conducted for entrainment reduction, the results of species- specific survival would be used to develop overall efficacy, which would include impingement survival.

As discussed in Section 3.2, all the ancillary issues associa ted with traveling water screens (e.g., handling and long-distance transport) apply to MIS. The one exception would be e limination of the concern with above- water biofouling as the system is submerged. The current heat treatment practices used with the existing screens (that would be effective, for underwater biof ouling of the traveling screens) would have to be relocated to be applicable here. If the MIS proved effective, and biofouling iss ues were documented during the pilot tests, a heat treatment alternative could be consider ed.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

4-2 Conclusion

The MIS is still considered a valid technology for impingement mortality r eduction. As with the traveling screen option, Alden is uncertain if this standard could be met with the spe cies present at HnGS.



### 4.3 F LOW 

### R EDUCTION

Prior to the Court’s Decision, EPA was considering issuing guida nce relative to the relationship of impingement and flow. EPA indicated they were considering guidance that would allow facilities to assume proportionality between flow and impingement. HnGS has complet ed its year of impingement sampling and these data could be analyzed to determine if diel and/o r seasonal impingement patterns occur during periods when HnGS could reduce flow. As with entr ainment, flow reduction remains an alternative but can only be considered in conjunction with another t echnology. That is, the curtailment in generation required to meet an impingement mortality reduction sta ndard of 80-95% is not practical or

cost-effective.

Conclusion

Consideration of flow reduction remains a possible alternative . Typically, flow reductions need to be discussed with Corporate Power Supply. Assessment of general trends in load demand can predict periods where placing a unit(s) on stand-by would result in some flow reduction credit. Shutting off pumps during high periods of impingement would result in the need to derat e the unit(s) to maintain thermal discharge limits. Use of variable speed drives could be considered to better control flow reductions and minimize lost generation. Costs for variable spe ed drives have been included in this Addendum. Regardless, neither option would likely meet the impingement morta lity reduction standard.



### 4.4 C LOSED



### - CYCLE COOLING

Closed-cycle cooling was assessed on a cursory level in the 2004 re port. LADWP is participating in the closed-cycle cooling retrofit cost evaluation study. The result s of this evaluation will identify the economic penalties associated with this option.

Conclusion

Closed-cycle cooling will meet all performance standards. How ever, Alden does not believe it is reasonable to consider it for impingement only.



### 4.5 A DDITIONAL 

### T ECHNOLOGIES

As with consideration of additional entrainment reduction alternat ives, there are other impingement reduction alternatives that have been suggested to be considered.

Passive screening (e.g., coarse-mesh barrier nets) requires low through-net velocities to exclude fish. The limitations discussed above for consideration of any installat ion in Long Beach Marina are also valid for this option. In addition, placement within the intake canal is al so questionable. Impingeable-size fish can avoid the net; however, the canal velocity is 1.3 feet/sec and the through-tunnel velocity is 5.0 feet/sec. A fish that is excluded from continuing down the canal could not retu rn to the marina basin. Therefore, Alden does not consider a passive screening system to be a viable alterna tive for HnGS.

The concept of installing cylindrical wedgewire screens in the intake c anal discussed in Section 3 can also be considered for impinged fish. However, the efficacy of the bypass pump with impinged fish would

have to be determined.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

4-3 Finally, diversion systems such as angled screens or louvers for impingeable-size fish would be comparable to the systems discussed above for entrained fish. C ost estimates for this option have not been developed.

Conclusion

Although impingement-only alternatives are available, Alden does no t recommend further consideration of impingement-only options in light of the Court’s Decision.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

5-1 

## 5.0 COST UPDATE

The revised costs presented in Table 5-1 are an update of the estimated costs provided in Table 6-3 of the original report. The update includes an escalation from 2004 dollars to 2006 dollars , as well as changes in the site-specific factors that impact the installation and O&M of the com pliance alternatives. The detailed costs for a fish return systems for Ristroph screens and the costs for the fish bypass pipes associated with narrow-slot, wedgewire screens in the intake canal are provided in Atta chments C and D, respectively.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station5-2TABLE5-1.ALDEN’SAPPRAISALLEVELCOSTS OFEVALUATEDALTERNATIVES[LRT1]Estimated from Alden DatabaseAlternativeConstructionCosts(2006 $)ReplacementPower DuringShutdown(MWh)TotalCapitalCost(2006 $)1O&MCosts(2006 $)LostGeneration(MWh)2AnnualizedCapitalCosts(2006 $)3IncrementalAnnualizedO&M Costs(2006 $)1, 2TotalIncrementalAnnualizedCosts(2006 $)New screenhouses withfine-mesh Ristrophscreens with returnOption 14$18,373,0000$18,373,000 $1,267,000 6,899 $2,616,000 $1,458,000$4,074,000New screenhouses withfine-mesh Ristrophscreens with returnOption 25$19,518,000 0 $19,518,000 $1,267,000 6,899 $2,779,000 $1,458,000 $4,237,000Install coarse-meshRistroph screens withreturn Option 14$8,965,000 0 $8,965,000 $987,000 5,585 $1,276,000 $1,113,000 $2,389,000Install coarse-meshRistroph screens withreturn Option 25$10,110,000 0 $10,110,000 $987,000 5,585 $1,439,000$1,113,000 $2,552,000Install MIS in intake canal $6,417,600 0 $6,417,600$34,000 2,240 $914,000 $146,000 $1,060,000Limit the number ofoperating pumps$0 0 $0 $0 1,437,357 $0 $71,868,000 $71,868,000Install variable speeddrives on the CWP6$3,427,000 0 $3,427,000 0 0 $488,000 0 $488,000Retrofit plant with closedcycle cooling system7$236,544,000 1,468,000 $309,944,000$4,726,400 64,259 $39,594,000 $7,802,000 $47,396,000Narrow-slot wedgewirescreens with 1,000 footreturn pipe8$42,693,000 489,000 $67,143,000 $8,430,000 164,973$8,049,000 $7,962,000 $16,011,000Narrow-slot wedgewirescreens with a 15,000foot return pipe8$88,930,000 489,000 $113,380,000$16,855,000328,948$14,632,000 $16,387,000 $31,019,000Footnotes on next page.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station5-3Table 5-1 Footnotes1.Based on a cost for lost generation of $50 per MWh.2.Includes costs as a result of any power penalties associated with the technology.3.Alden assumed a discount rate of 7%, and an amortization rate of 10 years for the capital costs and 30years for the pilot study and down-time costs.4.Return Option 1 uses a single return pipe and relies on a heat treatment to clean.5.Return Option 2 uses two return pipes in which onepipe is dewatered and left to dry during cleanings.6.Variable speed drives alone will not meet the entrainment standard and would have to be used in combination with other technologies.7.Cooling tower costs based on EPRI study (EPRI 2002a).8.Costs are based on detailed quantity take-offs in Attachment D.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

6-1 

## 6.0 DATA GAPS AND UNCERTAINTIES

As with any assessment of alternatives, there are a number of data gaps and/or uncertainties associated with individual facility location, design, and operation for specific options. These uncertainties are further exacerbated by the variability of the biological communit y characteristics (e.g. diel/seasonal abundance, life stage, species) at the site.

The following table provides a summary of these uncertainty considerations for each of the alternatives

considered in 2004 and in this document for HnGS.

Alternative Data Gaps Uncertainties

Fine-mesh Traveling Screens  Length and species-specific

survival data from the screen and fish return line;

 Biofouling impacts; and

 Plant-side return survival.  Effective mesh size;

 Effective approach velocity;

and

 Annual variability in species composition.

Coarse-mesh Traveling Screens  Length and species-specific

survival data from the screen

and fish return line.

 Biofouling impacts; and

 Plant-side return survival.  Annual variability in species composition.

Modular Inclined Screens  Length and species-specific

survival data from the screen and fish return line;

 Biofouling impacts;

 Plant-side return survival; and

 Only 2.0 mm slot width has

been tested.  Effective mesh size;

 Effective approach velocity;

and

 Annual variability in species composition.

Narrow-slot Wedgewire Screens with Fish-friendly Bypass Pumps  Length and species-specific exclusion data;

 Length and species-specific survival data to the bypass pumps, through the bypass pumps, and through the fish return line;

 Biofouling impacts; and

 Plant-side return survival.  Effective mesh size;

 Effective “sweeping” velocity; and

 Annual variability in species composition.

Flow Reduction   Generation demand; and

 Annual variability in species composition.

Closed-cycle Cooling Unit-specific retrofit.

The data gaps that exist with species composition, survival, and diel/seasonal presence and variability can only be reduced by extended abundance sampling (i.e. IM&E studies) or alternative/component-specific pilot studies. Each technology will have a different efficac y for reduction in station effects. The pilot studies proposed for LADWP’s Harbor Generating Station (i.e. f ine-mesh traveling screens) and HnGSAn Addendum To The 316(B) Evaluation Of The Haynes Generating Station

6-2 (i.e. MIS) will provide data on length-related, species-specific survival. The results of both studies would also provide survival data that apply to impingement (coarse -mesh screens). Macrofouling on the continuously operating screens can be determined during the pilot st udies as well as debris handling capabilities.

The type of study to assess efficacy of the narrow-slot wedgewi re alternative at HnGS is complex. The study would effectively be based on a biological mass balance. T he mass balance would first require a comparison of the density and condition (i.e. live or dead) of entr ainable-sized organisms within the intake canal upstream of the wedgewire complex and downstream of the complex prior to passage through the bypass pump. The survival of the organisms through the pump would then be determined by concurrently sampling the pump discharge with the “pre-pump” inlet s ample. This second effort may be unnecessary if the results of the first component are unfavorable.

Macrofouling and subsequent predation on entrained organisms could be a ssessed during a pilot study. However, a more prudent approach would be to develop an effective return line treatm ent technique based on actual plant operating data.

Pilot studies could also reduce the uncertainties of the eff ects of mesh size and approach velocities on organism survival. These issues, however, would probably be best determined after results from the

above studies were available.

The uncertainties associated with annual variability in speci es abundance and composition as they relate to the ability to meet performance standards cannot be reduced by pil ot studies. It is anticipated that survival among “hearty” and “fragile’ species will vary and a change in composition towards “fragile” species will jeopardize compliance potential.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

7-1 

## 7.0 CONCLUSIONS

This assessment indicates that:

• The re-powering project for Units 3 and 4 reduced flow by approximat ely 5% and slightly

lowered velocities within the intake canal. This flow reduction should be considered when developing deviations from the calculation baseline. However, t he differences do not change any of Alden’s original technology assessments.

• The two new technologies currently available (i.e., Hydrolox and Ge iger screens) can be considered in the same category as modified Ristroph screens. B oth of these systems function on the “trap and transfer” concept and require the same type of fi sh and debris returns as Ristroph screens. The potential use of either of these technologies doe s not change Alden’s previous

assessment.

• The 2006 impingement and entrainment data do not alter Alden’s selec tion of appropriate technologies for consideration in reducing entrainment at HnGS. The overall efficacy of any entrainment reduction technology is mitigated by the predominance of very early life history

stages.

• The Court’s Decision to remand restoration and the cost-benefit t est severely limit LADWP’s options, but do not affect Alden’s technology and operational measures assessme nts.

• Conclusions for entrainment:

 Closed-cycle cooling is the only option identified that will meet all pe rformance standards.

The ultimate reduction in flow associated with a marine installation wa s not determined. The station effects of installation of closed-cycle cooling associated wi th the re-powering of Units

5and6 are not included at this time.

 Fine-mesh traveling screens are technically an “exclusion technology.” H owever, unlike narrow-slot, wedgewire screens that depend on an air-burst cleaning syste m coupled with ambient currents to “carry” impinged fish and debris away from the CWIS, t his technology utilizes a “trap and transfer” concept. The process of collecting orga nisms to assess survival imparts some level of mortality, which is difficult to ascertain in the field. Consequently, the projected efficacy of this technology will be less than that for narrow -slot, wedgewire

screens.

 As with the fine-mesh traveling screens the projected efficacy of MIS will be less than that for narrow-slot, wedgewire screens. However, depending on the ultimate effi cacy for the fine-mesh screens, this alternative may be as effective as the other fine-mesh screen options.

 Consideration of flow reduction remains a possible alternative. Typical ly, flow reductions need to be discussed with Corporate Power Supply. Assessment of general trends in load demand can predict periods where placing a unit(s) on standby would result in som e flow reduction credit. Use of variable speed drives could be considered to better control flow reductions. However, this alternative alone would not meet the entrai nment reduction

standard.

 Either variation of the wedgewire technology or MLES that requires use of a bypass pump would certainly be questioned as to the efficiency of “moving” impinged fish a nd debris to the bypass pump and the effect of the pump passage on survival. Alden does not believe this approach could be proven to be effective in meeting the entrainment reduction perf ormance standard. An offshore installation of wedgewire screens was not conside red practicable.

 If EPA does not designate closed-cycle cooling as BTA, pilot studies would be nec essary to determine the “best performing” entrainment reduction technology.An Addendum To The 316(B) Evaluation Of The Haynes Generating Station

7-2 • Conclusions for impingement only:

 Coarse-mesh traveling screens are still a viable alternative fo r impingement mortality

reduction.

 Consideration of flow reduction remains a possible impingement mortality r eduction alternative. The same comments previously discussed for entrainment red uction apply to this

alternative.

 Although impingement-only alternatives are available, Alden does not rec ommend further consideration of impingement-only options in light of the Court’s Decision.

 Based on the Court’s Decision, it is anticipated that a schedule extension wil l be provided to accommodate the rulemaking process. That time can be used to pursue pilot st udies and continue to consider additional options.Attachment A An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

1 

## ATTACHMENT A -

SUMMARY OF 2004 EVALUATION OF H N 

## GS

The following provides a summary of the “Evaluation of the Haynes Generating Stations with respect to the Environmental Protection Agency’s 316(b) Rules for Existing Faci lities”, December 2004, prepared by Alden Research Laboratory, Inc. (Alden) and Electric Power Research Insti tute (EPRI).

Scope of the Analysis

In response to the Rule, EPRI and Alden conducted a strategic assessme nt for Los Angeles Department of Water and Power (LADWP) Haynes Generating Station (HnGS). T his assessment evaluated the impact of the Rule on HnGS, including potential cost-effective compliance a lternatives, additional information collection needs, and relative budget impacts as a result of studies and com pliance alternatives.

The major component of this analysis was a preliminary evaluat ion of alternative fish protection technologies to meet the applicable performance standards for HnGS and discussion of approximate costs for the feasible alternatives. As part of this alternativ es analysis, Alden reviewed operational options for meeting the applicable performance standards.

This report addressed technologies, operational changes, and rest oration measures that LADWP could implement to meet the Rule. EPA’s favored approach was to redu ce total fish losses, which did not address AEI at the population and ecosystem levels. Therefore, t raditional measures of population and ecosystem health, such as species diversity and richness were n ot addressed. Further, EPA did not consider factors that influence populations such as compensatory m echanisms, species fecundity, and natural mortality. Therefore, these factors were not considered.

Technologies and Operational Measures

The preliminary evaluation of alternative technologies and operat ional measures that could be considered by LADWP to meet the impingement mortality and entrainment (IM &E) standards at HnGS was presented in the report.

Alden’s preliminary judgment on how likely these alternatives were to actually meet these standards was

summarized as follows:

Alternative Will It Meet the Impingement Mortality Reduction
Standard? Will It Meet the
Entrainment Reduction
Standard?

New screenhouses with fine-mesh Ristroph screens Yes, provided that impingement survival of key species is at least

80% Yes.

Install coarse-mesh Ristroph screens in existing screenhouses Yes, provided that impingement survival of key species is at least

80% No

Install Modular Inclined Screens (MIS) in existing intake canal Yes No. However, some reduction in entrainment of larger organisms is expected as a
result of the 2 mm slot size

Limit the number of operating

pumps No; we might expect some
reduction in the number of fish impinged Yes, with a 60% reduction in plant flow

Retrofit plant with closed-cycle cooling system Yes YesAttachment A An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

2 The annualized costs of these alternatives as compared with the costs EPA used in developing the Rule

were:

Alternative Alden’s Annualized Costs EPA’s Annualized Costs

New screenhouses with finemesh Ristroph screens $3,397,000

Install coarse-mesh Ristroph screens in existing screenhouses $1,899,000

Install MIS in existing intake
canal $936,000

Limit the number of operating

pumps $57,494,000

Retrofit plant with closed-cycle cooling system $45,099,000 $1,237,176

Key findings of our preliminary (2004) analysis are:

• The existing Cooling Water Intake Structure (CWIS) will not m eet the IM&E performance

standards.

• Five technological or operational options (i.e. build new scree nhouses and install fine-mesh Ristroph screens; install coarse-mesh Ristroph screens in exi sting screenhouses; install MIS units; limit pump operation; and closed-cycle cooling) were considered to have potential for meeting the impingement mortality and/or entrainment reduction standards and were deemed practicable from an engineering standpoint. Technologies that solely reduce i mpingement were also

evaluated in case LADWP were to meet the IM standard with a technology while meeting the entrainment standard through operational changes or initiating restorati on measures.

• For the three options that could meet the entrainment reduction sta ndard, Alden estimated the annualized costs range from $3,397,000 3 for new screenhouses with fine-mesh Ristroph screens to $57,494,000 for reducing flow during periods of high entrainment.

• Coarse-mesh Ristroph screens in the existing screenhouses would meet the impingement mortality (IM) reduction standard at an annualized cost of $1,899,000. Fine-mesh Ristroph screens in the existing screenhouses may be able to meet bot h the IM&E standards and would have a cost similar to that of coarse-mesh Ristroph screens . Pilot studies would be required to prove the effectiveness of fine-mesh Ristroph screens at the ve locities in the existing

screenhouses.

• MIS units installed in the intake canal were the most cost eff ective alternative to meet the IM reduction standard with an annualized cost of $936,000. As the MIS unit s are designed with 2 mm slots, they would also reduce entrainment of larger organisms.

The following general considerations were used to develop concept ual designs of alternative fish protection technologies for application at HnGS. Alden used the crit eria to evaluate the relative advantages and disadvantages of each option and to select for c onsideration those technologies with the greatest potential to meet the performance standards at HnGS. The cr iteria were:

• Alternatives should be designed to reduce impingement mortalit y by 80–95% from the

“calculation baseline.”

3 See Table 6-1 (Revised) for updated costs.Attachment A An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

3 • Alternatives should be designed to reduce entrainment by 60–90% f rom the “calculation

baseline.”

• Alternatives should provide protection for species that are pote ntially susceptible to IM&E at

HnGS.

• The period of protection is year-round for impingement and May through August for e ntrainment.

• Alternatives should take into consideration current project desig n features, as summarized in

Table 3-14.

• Alternative designs should have suitable conditions for fish prot ection over the full range of intake flows and water depths at the CWIS.

• Alternatives should provide effective protection throughout the entir e water column such that they are effective with all species potentially susceptible to IM &E.

• Alternatives should function under expected debris loading and hydrau lic conditions in the Long Beach Harbor (i.e., reasonable cleaning techniques are available and demons trated).

• Alternatives should preserve, to the extent possible, the existing civil/ structural features.

• Alternatives should meet worker and public safety requirements.

• Alternatives should not adversely impact navigation.

• Alternatives should be compatible with the other aesthetic and recreationa l features of the region.

The screening process was as objective as possible. However , in assessing the potential for application of fish protection schemes under physical, hydraulic, and in environment al conditions that they have never been applied, the Team had to use best professional judgment based upon experience.

The Team deemed a technology to have proven biological effective ness if test data (preferably from fullscale application) were available that documented a technology’s effectiveness with one or more of the species present at that site. If engineering data exist i n sufficient detail to develop a conceptual design and/or if the technology has been constructed at another site, it w as judged it to be an available technology. Each technology was qualitatively assessed to identi fy whether it had biological and/or engineering advantages over the other alternatives. For exampl e, an intake technology that has been proven effective at reducing losses for many species and under a variety of intake conditions has a biological advantage over one that has been proven effective with a few species or under limited intake conditions. From an engineering perspective, one technology may hold an advantage over another if the civil/structural requirements for its installation are substa ntially less.

Behavioral barriers to protect juvenile and adult fish have been the subject of extensive research. The use of strobe lights to elicit a behavioral response is supported by the results of laboratory and cage test studies that have demonstrated strong avoidance by several f ish species to strobe lights. Strobe lights have been evaluated for repelling or guiding juvenile and adult fish away from water intakes (EPRI 1994, 1999) and, in many cases, toward bypasses for transport to a safe rel ease location. There is some evidence that combining strobe lights with an air bubble curtai n can provide effective fish deterrence. However, results have been species- and site-specific.

The focus of recent studies involving underwater sound technologies has been on the use of low- and high-frequency acoustic systems that were not available for commercial use until the 1990s. Highfrequency (120 kHz) sound has been shown to effectively and repeatedly repel members of the genus

Alosa (American shad, alewife and blueback herring) at sites throughout the U.S. (Ploskey et al. 1995;

4 See Table 3-1 (Revised) for updated assessment.Attachment A An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

4 Dunning 1995; Consolidated Edison 1994). Other studies have not shown sound to be consistently effective in repelling species such as largemouth bass, smallm outh bass, yellow perch, walleye, rainbow trout (EPRI 1998), gizzard shad, Atlantic herring, and bay anchovy (Consolidated Edis on 1994).

Based on the results of behavioral barrier studies conducted over t he past 30 years, a hybrid barrier consisting of light, sound, and air bubbles would be most effective on Alos ids. Given that Alosids are not impinged at HnGS, a hybrid barrier would likely not reduce impingem ent to a level that meets the impingement mortality reduction standard, and thus the Team eli minated these types of barriers from

further consideration at HnGS.

The existing screenhouses at HnGS could be modified for installat ion of Ristroph screens. Ristroph screens are very similar to conventional traveling water s creens except that they are designed with extra features to collect and transport impinged organisms safely bac k to the waterbody. Fine-mesh Ristroph screens with an approach velocity of 0.5 feet/sec have the potentia l to meet both standards, while coarsemesh Ristroph screens may meet only the IM standard. In addition, R istroph screens are designed for continuous operation to minimize impingement duration. Continuous rotation along with spray wash systems provides the Ristroph screens with an automatic scree n-cleaning feature. This gives them an engineering advantage over fixed-screens, barrier nets, and bar r ack barriers, all of which would require an additional cleaning system. Fine-mesh Ristroph screens wit h expanded screenhouses are considered to be a viable alternative for reducing both impingement and entrainment mortality at HnGS. Coarse-mesh screens in the existing screenhouses were also evaluated, since HnGS may choose to meet the entrainment reduction standard through other compliance measures.

Modification of the screenhouse to incorporate physical barriers or diversion systems, such as angled screens to prevent impingement, would be difficult. Traveling w ater screens have an engineering advantage over other physical barriers (i.e. angled fixed-sc reen, rotary drum screen, barrier net, bar rack barrier, infiltration intakes, and porous dikes). Installation of rot ary drum screens and porous dikes would require a much larger area than conventional traveling scree ns because of the lower design velocity. Rotary drum screens are typically installed in channels wher e water elevations are relatively constant and water depths are less than 12 feet, which is not the case at the HnGS facility. Bar rack barriers are typically designed to have spacing greater than 1 in. and would not ef fectively prevent the entrainment of early life stages. They may, however, effectively reduce i mpingement. None of these options were evaluated further because they do not have significant advantag es over other impingement mortality reducing technologies.

The MIS and Eicher screen have a biological and engineering advant age over louvers, angled bar racks, and angled screens in preventing impingement. Both screens offer the potential to effectively divert most species by using smaller structures than the other screening concepts. The MIS, for example, is designed to operate at velocities up to 10 feet/sec. The Eicher screen i s designed for installation in hydroelectric project penstocks and rejected for consideration at HnGS. An MIS configuration located in the intake

canal was chosen for further evaluation because the MIS should b e easier to build and maintain than other diversion systems.

Cylindrical wedgewire screens have an engineering advantage ov er the porous dike, infiltration intake, and bar rack barriers. Wedgewire screens are designed for a through-screen velocity of 0.5 feet/sec; therefore, automatically meeting the impingement mortality ( Compliance Option 1) standard. Wedgewire screens have cleaning features that make them easier to c lean than other fixed screens and barrier nets. However, this cleaning feature requires the presence of a s weeping current to be effective. In the marina wedgewire screens would be a navigational obstruction, and in the i ntake channel, there would be no sweeping current to help clean the screens. For these reasons, w edgewire screens were not included in the preliminary evaluation for HnGS.

Aquatic filter barriers (AFB) could perform a similar functi on to fine-mesh traveling water screens. An AFB has two layers of material with an air purge syste m installed between the layers to permit automaticAttachment A An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

5 cleaning of accumulated silt and debris. This cleaning system can also free impinged fish larvae and other non-motile life stages. However, this technology requires an extremely large surface area. An AFB at HnGS would be impossible to place within the marina due to the amount of surface area required. Therefore, this technology was not considered a viable alternative for HnGS.

Fine-mesh barrier nets (<0.5mm) are easily fouled by silt an d algae, require labor-intensive cleaning, and are considered experimental for reducing entrainment. However , coarse-mesh nets could reduce impingement if they were installed in a low velocity zone and per iodically cleaned to remove debris accumulation and biofouling growth. Barrier nets require less su rface area than AFBs, although they would still hinder navigation and recreation at the Long Beach Mar ina. Therefore, barrier nets were not included as an option to reduce impingement at HnGS.

The preliminary screening of intake technologies available for fish protection indicated that installation of

fine-mesh 5 Ristroph screens with an expanded intake was the one intak e alternative that had the greatest potential for application to reduce fish impingement mortality and entra inment at HnGS:

Two additional intake alternatives that would act to reduce fish impingem ent only were also included:

• Installation of coarse-mesh Ristroph screens in existing intake; and

• Installing modular inclined screen (MIS) in intake channel

Two flow reduction options were identified to reduce entrainment and, to a le sser extent, impingement:

• Reduced circulating water pump operation; and

• Installing closed-cycle cooling system

Plant operating procedures dictated operation of all pumps per unit t o maintain the plant discharge within the permitted thermal limits. Additional flow limitations coul d be implemented during periods of peak abundance of entrainable organisms. To maintain the plant disch arge within the permitted thermal limits, reduced pump flow may require a reduction in plant output. Variable speed drives were selected as the flow reducing technology.

Closed-cycle cooling could greatly reduce both impingement mortal ity and entrainment at HnGS. Mechanical or natural draft wet towers would require less m odification to the existing circulating water system piping and less real estate than dry cooling towers. The costs for constr uction of a wet mechanical cooling tower are about 60% less than the natural wet cooling tow er. Natural wet cooling towers require less energy to operate and have lower annual costs then a wet mechanical draft tower. However, wet mechanical draft towers generally have less aesthetic and air quality impacts than natural draft wet towers. HnGS is surrounded by residential, recreational, and par k areas, therefore aesthetics and air quality issues would probably rule out the use of natural draft towers. For these reasons, the Team evaluated wet mechanical draft towers as the closed-cycle cooling sy stem option for HnGS.

5 The term “fine-mesh,” as used in this document, ref ers to 0.5 mm (0.02 in.) square woven mesh.Attachment B An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

1 

## ATTACHMENT B -

LADWP RESTORATION OPTIONS

1.0 INTRODUCTION

In 2004, Alden Research Laboratory (Alden) and the Electric Power R esearch Institute (EPRI) conducted a 316(b) strategic assessment for the Los Angeles Department of Water and Power’s (LADWP) Generating Stations; Harbor Generating Station (HGS), Haynes G enerating Station (HnGS), and Scattergood Generating Station (SGS). As part of that assessme nt, the use of restoration as a 316(b) compliance alternative was evaluated. That evaluation analyz ed restoration project categories, and included summaries of nationwide restoration projects.

The purpose of this appendix is to update the Alden and EPRI eval uation, provide information on specific projects applicable to offsetting entrainment and/or impingement losses at the LADWP Generating Stations, summarize the process of implementing restoration pr ojects, and identify data gaps that are required to be addressed prior to developing a 316(b) Restoration Plan for incl usion in the Comprehensive Demonstration Study for each Generating Station.



## 2.0 SUMMARY OF 2004 ALDEN/EPRI RESTORATION EVALUATION

2.1 T YPES OF R ESTORATION A PPLICABLE TO 316( B )

The Alden/EPRI evaluation identified several categories of restoration projects that have been used at

other facilities nation-wide. These included:

• Wetlands restoration;

• Fish stocking;

• Submerged aquatic vegetation (giant kelp) restoration;

• Provision of fish passage;

• Contribution to a restoration fund; and

• Water quality improvements.

The two general requirements for the use of restoration are (1) a demonstration that the use of technologies and/or operational measures was evaluated, and the use of restoration measures is appropriate because meeting the performance standards through implem entation of technologies and/or operational measures is less feasible, less cost-effective , or less environmentally desirable than meeting the performance standards in whole or in part through the use of restoration, and (2) a demonstration that the use of restoration will produce ecological benefits (production o f fish and shellfish) at a level that is substantially similar to that which would be achieved through imple mentation of technologies, operational measures, and/or alternative site-specific requirements.



### 2.2 S PECIFIC R ESTORATION E XAMPLES FOR HGS, H N GS, AND SGS

Alden/EPRI provided several examples of potential restoration projects applicable to LADWP’s coastal generating stations. These examples are summarized below.

Fish Stocking

Stocking of fish would provide direct replacement of affected sp ecies. Examples included stocking of lake sturgeon (Coosa River, Georgia/Alabama), Atlantic Stu rgeon (Patuxent River, Maryland), American shad (Susquehanna River, Maryland/Pennsylvania), and white seabass (southe rn California).Attachment B An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

2 Habitat Protection Programs

Habitat restoration, and particularly wetland restoration, has be come increasingly popular due to the decline of various habitats with time. Participation in a restoration progr am would also provide the benefit of fish production. Examples included the San Dieguito Lagoon restorat ion (SCE San Onfore), the Morro Bay Habitat Enhancement Program (Duke Energy Morro Bay), the De laware Bay Estuary Enhancement Program (PSEG), and the Santa Monica Bay Restoration Commission ( Los Angeles, California). Other examples were provided related to restoration-related groups that might assist in the facilitation of restoration projects, including the National Centers for Coasta l Ocean Science, the National Estuaries Restoration Inventory, the NOAA Community-based Restoration Program , the U.S. Fish and Wildlife Service Partnership for Fish and Wildlife, and Coastal Americ a’s Corporate Wetlands Restoration Partnership.

Dam Removal or Fishway Construction

The U.S. Fish and Wildlife National Fish Passage Program is de signed to restore native fish and other aquatic species to self-sustaining levels by reconnecting habit at that has been fragmented by barriers, where such reconnection would not result in a net negative ecolog ical effect. Examples included installation of fishways (Delaware Bay), and a potential da m removal project (Rindge Dam, Malibu Creek).

Alternative Restoration Projects

Other potential restoration projects could include runoff a batement programs and removal of contaminated sediments to improve water/sediment quality and habitat.



### 2.3 316( B ) R ESTORATION I MPLEMENTATION P ROCESS

The use of restoration as a compliance alternative will requi re coordination and agreements among a number of regulatory agencies and stakeholder groups. If LADWP decides to implement a project that it would fund and manage in cooperation with federal, state, and local r esource agencies, the process could include the following at a minimum:

• Identify projects with involvement of resource agencies and st akeholder groups using an approach similar to the process described in Section 3.4.

• Scale project to meet desired goals for offsetting losses a ttributable to impingement mortality and entrainment (IM&E).

• Develop implementation plan for restoration with input from res ource agencies and stakeholder groups including:

 Setting goals for project

 Defining milestones that can be used to measure performance

 Conducting initial biological and engineering data for plan

 Developing a verification monitoring plan to ensure that milestones are being met and the goals for offsetting IM&E losses are achieved

 Ensuring that the plan incorporates adaptive management so that restorat ion activities and monitoring can be modified to ensure that the final goals of the project ar e achieved

• Prepare information for permitting

 May require preparation of Environmental Impact Report and responding to comm ents from reviewers that will result in modifications to the project and cha nges to the implementation and monitoring plans.

• Use implementation plan to develop requests for proposals for engineering and c onstruction.

• Review proposals and select contractors for management, construction, and m onitoring.Attachment B An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

3 • Implement verification monitoring and schedule periodic updates on progress and continue reviews involving resource agencies and stakeholders.

Due to the complexity, cost, and time involved in this process, another option is to fund an existing project. LADWP could contribute money to the project and ensure t hat the existing verification monitoring plan will supply the necessary information to ensure t hat the goals of the restoration are being achieved. Additional funding may be necessary to ensure that verifi cation monitoring is adequate. An example of the successful implementation of this approach is the f unding provided from the Moss Landing Power Plant (MLPP) to the Elkhorn Slough Foundation (ESF) f or their programs related to the preservation and enhancement of the Elkhorn Slough National Estuar ine Research Reserve (see attached). The success of this program has been widely recognized, and is la rgely due to the maturity of the management plan for the slough that was developed by the ESF. The E SF has been able to leverage the money provided by MLPP many times over to accomplish much more than could ever be ac hieved from a single restoration project. The successful implementation of th is approach requires identifying an existing entity like the ESF that has a proven track record with implementing rest oration programs.



## 3.0 SPECIFIC RESTORATION PROJECTS APPLICABLE TO HAYNES
GENERATING STATION

The purpose of this section is to identify specific, local re storation projects that are potentially applicable to the HnGS, and identify data necessary if each project w ere to be selected for implementation. Potential restoration projects should be considered based on their ability t o offset entrainment and/or impingement

at HnGS.

Any specific conservation, enhancement, or restoration project that is to be used for this purpose should have a nexus (i.e., offset) to the IM&E effects of the power pla nts. The projects that were evaluated to offset potential IM&E losses fell into three basic categories:

• Projects that would directly restore or enhance habitat in the vicinity of HnGS (Los Angeles and Orange counties);

• Projects that enhance habitat through watershed management; and

• Projects that enhance the nearshore coastal environment in the vicinity of HnGS (Santa Monica Bay and San Pedro Bay).

Projects that result in removal of accumulated sediment from coastal wetlands would increase the coastal salt marsh habitat, which would, in turn, increase their biologic al productivity. Projects that restore the

tidal flow between the ocean and the wetlands to historic l evels would have a similar affect on productivity. Other projects that involve watershed management c ould reduce wetland sedimentation and thus preserve existing wetland habitat. Projects that enhanc e the biological productivity of Santa Monica and San Pedro bays could directly offset the loss of productivity in the same waterbody that occurs as a result of IM&E losses at the three power plants.

The “value” of the ecological services or benefits that wil l result from implementation of any of these restoration projects will be assessed using various habitat mode ls to demonstrate that the ecological “credits” gained through restoration will outweigh the ecological “deb its” caused by the IM&E losses.

Using local environmental planning documents and resource agency rec overy plans as references, three major categories of projects have been identified that are appropriate for inclusion as restoration alternatives to offset IM&E losses. These projects hav e the potential to create, restore and preserve habitat equivalent to the amount of habitat that produced the estima ted numbers of impinged and entrained species of fishes and target invertebrates, as w ell as the other ecological and environmental effects of I&E. Restoration projects are presented that of fset potential population effects of IM&E on specific species and at the same time contribute to the overall health of nearshore/coastal habitats.Attachment B An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

4 

### 3.1 C OASTAL W ETLAND P ROJECTS

At one time coastal lagoons, salt marshes, and other wetlands crea ted by the merging of creeks and rivers

with the Pacific Ocean characterized the shoreline of Santa Mon ica Bay, Los Angeles and Long Beach Harbors, and shoreline areas further south. As these coastal areas became more densely populated, and more highly developed, most of the marshes were filled and the c reeks and rivers were channeled into concrete waterways to eliminate the periodic flooding that pla gued these low lying areas. In recent years, public sentiment has turned to the task of preserving the rema ining wetlands in this area and, where possible, to restoring those wetlands to a state that more closely re sembles historic conditions.

This category of projects includes actions taken directly within the boundar ies of these wetlands to restore and/or enhance habitats that serve as spawning grounds for fish and o ther aquatic species. Projects in this category include the restoration of historic sediment elevati ons, the redirecting of freshwater streams into the channels that historically fed these areas, and the reopening of channels to the ocean that allow tidal

flow into and out of the wetlands.

The anticipated results of restoring and protecting the wetland habitats will be used to forecast the project’s qualitative and quantitative benefits relative to baseline IM&E losses. Projects considered for evaluation include several within Santa Monica Bay as well a s projects in nearby Orange County. Project summaries are presented in order of coastwise location (upcoast to downcoa st)

3.1.1 Zuma Wetlands

Zuma Wetlands is a small, 6-acre, freshwater marsh and cr eek situated about 50 miles upcoast of the HnGS. The wetlands have historically served as a wildlife c orridor and nesting site for a variety of birds and small mammals. By the early 1990s periodic dumping of surplus const ruction and road building material had heavily impacted the wetlands and surrounding uplands. T he existing wetlands were greatly reduced and, in many areas, native species were completely repla ced by exotic ornamental trees, annual grasses, fennel, mustards, and thistles. High visitation at Zuma Beach ha s also impacted the site.

Wetland restoration efforts commenced in 1998 and include the exca vation of construction fill, recontouring of upland habitats, removal of exotic plant species, planting of more than 5,000 native plants, and the re-creation of an additional 21⁄2 acres of freshwate r wetland/dune/riparian habitat. Restoration of this wetland is an ongoing process, which continues at this ti me.

3.1.2 Malibu Lagoon

Located approximately 45 miles upcoast of the HnGS, Malibu Lagoon is a coastal lagoon and salt marsh fed by Malibu Creek and its associate watershed. During much of t he rainy season (winter and spring) the lagoon opens into the northern end of Santa Monica Bay. During the summ er and fall, reduced flow from the creek and seasonal rebuilding of the beach area dams the la goon and cuts off its connection with the ocean except during periods of extreme high tide and/or large ocean swells. Lacking a connection to the ocean the lagoon becomes a brackish water body whose salinity fluctua tes with freshwater input and evaporation. Several habitat restoration or enhancement project s are in existence that affect the Malibu Creek and Lagoon directly, or indirectly, due to their influence on cr eeks that are tributaries of Malibu

Creek.

3.1.3 Topanga Lagoon and Creek

Historically the Topanga Lagoon covered more than 30 acres, but has now been reduced to only 2 acres (mostly due to the deposition of 800,000 cubic feet of fill into the lag oon during the 1934 realignment of the Pacific Coast Highway). Located approximately 42 miles upcoa st of the HnGS, the lagoon is fed by Topanga Creek and its associated watershed. Over the years, de velopment in the area has increased sedimentation rates, which constrain the channel and impede fish mi gration by species that include the endangered Steelhead trout. Upper Topanga Creek is listed on the St ate 303(d) list of impaired waterbodies. The Santa Monica Bay Restoration Commission, in conjunc tion with other agencies, has conducted a comprehensive Topanga Creek Watershed and Lagoon Restorat ion Feasibility Study toAttachment B An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

5 identify ways to restore these resources. The California D epartment of Parks and Recreation recently purchased 1,659 acres of lower Topanga Canyon including the current and historic lagoon sites.

3.1.4 Ballona Wetlands

Located about 24 miles upcoast of the HnGS, the Ballona Wetlands cont ains saltwater marsh, freshwater marsh, coastal bluff, and dune habitats. The area, at one time, covere d approximately 2,000 acres, but due to human encroachment and development the wetland has been greatly re duced over the last 100 years. In recent years, about 340 acres of the wetland has been preserved due t o the efforts of numerous organizations that are dedicated to the preservation and restora tion of the wetland. These organizations include Friends of Ballona Wetlands, the Ballona Wetlands Foundation, and Heal The Bay. Portions of the wetland include tidally influenced marsh areas that act as a nursery for Santa Monica Bay marine species. Restoration plans for this portion of the wetland ar e still being developed. Ballona is the only remaining large coastal wetland in Los Angeles County.

3.1.5 Los Cerritos Wetlands

The Los Cerritos Wetlands is located immediately adjacent t o the HnGS. The wetland straddles the Los Angeles-Orange County border. It currently consists of about 130 we tland acres, with nearly 800 acres of degraded habitat proposed for restoration. Historically it consis ted of about 2,400 acres and included what is now Alamitos Bay. Since much of the site was modified due to former oil development activities, most of the land was privately held. In 2006, the California Coastal Conse rvancy was one of several agencies that purchased 66 acres of the wetlands, and hopes to acquire more. The Los Cerritos Wetlands Land Trust of Long Beach and Seal Beach is one organization committed to restoration of the wetlands. A conceptual restoration plan includes full tidal restoration ( inland to Westminster Avenue) via connection to the lower San Gabriel River. While the proximity of the Los Cerritos Wetlands to the HnGS makes it an attractive restoration option, other considerations associat ed with the project make it less than ideal. The recently submitted final report of the City of Long Beach, Los Cerritos Wetlands Study Group (available as a downloadable pdf file at http://www.longbeach.gov/plan/pb/cpd/los_cerritos.asp ) cited several pressing issues that need to be dealt with in order to pr oceed with any of the proposed restoration projects. Two of these issues are the numerous and varied zoning a nd jurisdictional concerns related to the area of the former wetlands, and the area’s history of use a s a hazardous waste disposal site. These concerns are reflected in the ranking of this restoration option.

3.1.6 Bolsa Chica Lowlands

The Bolsa Chica Lowlands Restoration Project is located abou t 5 miles downcoast from the HnGS adjacent to the City of Huntington Beach. The purpose of the proje ct is to restore portions of the wetland ecosystem of the Bolsa Chica lowlands. The project area cove rs about 1,247 acres, and has restored tidal

influence from the Pacific Ocean to about one-half of this area to reinvigorate the wetland ecosystem. To achieve the biological benefits of tidal restoration, a direc t connection to the Pacific Ocean was reestablished through the creation of a new tidal inlet that cut through Bolsa Chica State Beach and crossed the Pacific Coast Highway near the Huntington Mesa. Constr uction is currently underway and is anticipated to span a total of 2.5 to 3 years, in order to avoid or minimize impacts to fish and wildlife resources, coastal traffic, and beach recreation.

3.1.7 Huntington Beach Wetlands

The Huntington Beach Wetlands are located about 11 miles downcoast f rom the HnGS, adjacent to the Huntington Beach Generating Station (HBGS). The total area of the we tlands is about 180 acres. Over the years, the wetlands have been divided into a number of smaller parcels by the development of the Huntington Beach area. The Huntington Beach Wetlands Conservancy plans t o acquire the entire 180 acres and restore it in accordance with a comprehensive wetlands restoration plan that they are currently preparing. Restoration will include the improvement or re-establis hment of tidal circulation within the wetlands. This will provide additional habitat for local fish a nd invertebrate species. In fall 2006, AES Huntington Beach was required to restore 66.8 acres of the Huntington Bea ch Wetlands to offset

entrainment losses for Units 3and4.Attachment B An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

6 3.1.8 Upper Newport Bay Ecological Reserve

Newport Bay is located approximately 15 miles downcoast from the HnGS. The Upper Newport Bay Ecological Reserve was created in 1975 as result of the purchas e of 527 acres of land in and around the bay from the Irvine Company and the transfer of 214 acres of tidal wetlands from the County of Orange to the State. An additional 11 acres of land in Big Canyon was added i n 1982 bringing the total acreage of the Ecological Reserve to 752 acres. It is managed by the Cali fornia Department of Fish and Game (CDF&G). There are currently a number of restoration projects within Upper Newport Bay. The largest is the dredging of 2.1 million cubic yards of sediment. The project will restore and maintain tidal movement within much of the Bay. Much of the dredging project still needs funding, as well as post-project monitoring and maintenance. Dredging will provide additional habita t for fish species already present in Upper Newport Bay.



### 3.2 C OASTAL W ATERSHED P ROJECTS

Projects that control or reduce sediment transport into coasta l wetlands may include erosion control projects along upland watercourses; construction of catchment basi ns, swales, and other sediment containment features; land acquisition for purposes of creating conse rvation easements; minimizing runoff from development activities; restoration of floodplain habi tat; and other Best Management Practices. The implementation of watershed management projec ts as part of the restoration plan is based

on the nexus between the loss of wetland area and its associated r eduction of biologically productive habitat with the infilling of the wetlands by sediments eroded from its wate rshed.

3.2.1 Las Virgenes Creek Restoration Project

Las Virgenes Creek is an important tributary of Malibu Creek and Lagoon. Las Virgenes joins Malibu Creek approximately 5.5 miles from the coast (Malibu Lagoon). The City of Calabasas plans to remove over 250 linear feet of a concrete lined portion of the creek t o help restore the natural flow and reduce sedimentation in the lower creek, and Malibu Creek and Lagoon. Strea m banks will be stabilized using a bio-engineered revetment and replanted with native vegetation.



### 3.3 P ROJECTS TO E RADICATE N ON -N ATIVE P LANTS F ROM W ETLANDS

A number of projects have been proposed, or are underway, to eradic ate non-native/invasive plants from several of the creeks that feed the wetlands along the shore o f Santa Monica Bay and areas to the south. Plants like the Giant Reed (Arundo donax) clog waterways, incr ease sedimentation, and consume large quantities of water. Removal of these plants can help restore f low within these coastal creeks and marshes to historic levels. Non-native plant eradication programs are currently underway in lower Topanga Creek, Malibu Creek, and Solstice Creek (a tributary of Malibu Creek).



### 3.4 N EARSHORE C OASTAL P ROJECTS

Projects for enhancing nearshore coastal areas include restor ing degraded habitat such as kelp beds and rocky intertidal areas, and projects that establish new habit at such as the construction of artificial reefs. The increased biological productivity resulting from these proje cts can be weighed against the IM&E losses associated with the operation of coastal generating stations.

3.4.1 Restoration of Natural Resources in Rocky Intertid al Habitats in Santa Monica Bay

The UCLA Institute of the Environment currently has funding from the Santa Monica Bay Restoration Commission (as part of the Santa Monica Bay Restoration Plan) for a project to identify the causes of degradation of the intertidal habitats in Santa Monica Bay. The project will identify, evaluate, and recommend practical restoration techniques for these habitats.Attachment B An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

7 3.4.2 Kelp Restoration

Santa Monica Bay Keeper has an ongoing kelp bed restoration p roject that has been partially funded as part of the Santa Monica Bay Restoration Plan. Historically, the rocky northern (Malibu area) and southern (Palos Verde peninsula about 19 miles west of HnGS) portions of the bay were once covered by dense kelp forests. Over the last 50 years the acreage of t hese beds has been greatly reduced. Several kelp restoration projects, including the efforts of Santa Monica Bay Keeper, have attempted, with some success, to return the kelp beds to their original extent. The te chniques employed include the removal of grazing herbivores (primarily sea urchins) and the introduction of laboratory-reared kelp plants into areas where kelp coverage has declined. Kelp beds provide habitat for numerous species of fish, invertebrates, and marine mammals. Increasing the size of the kelp beds in San ta Monica Bay or the Palos Verde peninsula to the west of HnGS, and the associated increase in bi omass that would accompany the restoration, could help offset IM&E losses due to operation of coastal generati ng stations.

3.4.3 Artificial Reef

Several artificial reefs have been constructed along the coas t of California, most notably the San Clemente Artificial Reef (SCAR) that was built as part of the mitigation for the San Onofre Nuclear Generating Station (SONGS) thermal discharge. SCAR was es tablished in 1999 and its performance has been monitored since that time. The artificial reef modules have provided new sub strate for giant kelp and other algae. The reef and its associated kelp canopy have, in turn, provided new habitat for fish and

invertebrates.

3.4.4 Restocking of Affected Fish Species

Hubbs-Seaworld Research Institute (HSWRI) operates aquaculture r esearch facilities in southern California and Florida. Since 1983, the HSWRI has bred, tagged, and released over 650,000 white seabass

into southern California waters. The institute has also bred and released other fish species, and is assessing the feasibility of breeding rockfish. The technology developed by the institute, as part of their Ocean Resources Enhancement Hatchery Program, could potentially be used to restock species, although the 316(b) regulations discourage a hatchery replacement approach.



### 3.5 P RELIMINARY R ANKING /E VALUATION OF R ESTORATION P ROJECTS

A set of selection criteria was developed for ranking the pros pective habitat restoration projects previously described, or any other comparable projects that might be considered for implementation. They include:

• Location • Cost effectiveness

• Nexus to IM&E effects • Ability to measure performance

• Basic need or justification for project • Success of comparable restoration projects

• Nature and extent of ecological benefits • Time before benefits accrue

• Stakeholder acceptance • Technical feasibility

• Administrative considerations • Opportunities for leveraging of funds/Availability of matching funds

• Consistency with ongoing resource agency work and environmental planning • Legal hurdles (e.g., permits, legal access)

• Implementation costs • Duration of benefitsAttachment B An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

8 Depending upon the nature of a particular project, the relative importance and weighing of these criteria may vary. As a general proposition, however, projects will be s elected so as to maximize the offset of IM&E effects for compliance with 316(b), and secondarily to optimiz e ecological benefits to Santa Monica Bay/San Pedro Bay, or adjacent offshore areas within the Southern California Bight. This process will ensure that the most effective projects are assigned the highest priority.

A description of each of the criteria is provided below:

Location

Ideally (5) the location of the project is in the same sourc e water/ receiving water bodies that are affected by the operation of the facility. Scores decrease as the dis tance between the project area and those waterbodies increases. Projects that involve waterbodies and wa tershed areas that feed into the affected areas can have a high ranking but are not ideal.

Nexus to facility’s IM&E effects

A project that enhances or replaces the species affected by the facility, in the waterbodies affected by the facility would have the ideal nexus (5). As the project moves away from those species and locales, its ranking decreases. The nexus is the relationship between the e nvironmental impacts resulting from the operation of the facility and the environmental benefits of the proposed projec t.

Basic need or justification for project

This category requires an evaluation of the need or justif ication for a proposed project. Restoration projects that return wetland areas to their historic exten t and replenish historic species that have been depleted may be easily justified (high score). However, if the project requires that several blocks of commercial property be razed to accommodate the project, it may require considerably more justification. Other projects, like the establishment of artificial reef s where none formerly existed, may be worthwhile but will require some justification for their adoption (lowered score ).

Technical feasibility

Is the technology or methodology utilized by the proposed project prove n and effective? Has it, or something similar, been used under similar conditions? Proven track record, or pi e in the sky?

Stakeholder acceptance

Is the proposed project likely to have the support and approval of t he regulatory agencies involved, the owners and operators of the facility, and the local citizenry?

Nature and extent of ecological benefits

This is a category of magnitude. Does the project have a re latively narrow and limited ecological benefit, such as increasing the population of a single species within a limited spatial context, or does it benefit a large number of species (directly and indirectly) over an extensive area (higher ranking).

Time before benefits accrue

If the proposed project is enacted, how much time will elapse befor e the benefits of the project become evident. Projects that will demonstrate their resultant bene fits in a short period of time will rank higher in this category. However, projects that will have a large ecol ogical benefit, but will require an extended period of time to come to fruition, will offset their lower ra nking in this category with a higher ranking in the previous (nature and extent of ecological benefits) category.Attachment B An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

9 Duration of benefits

Projects with environmental benefits that continue over a long period of tim e will receive a higher ranking than those with short-term, transient, benefits. This category w orks in conjunction with the two previous categories.

Success of comparable restoration projects

This category is similar to the “Technical Feasibility” category, but goes a step beyond feasibility to the question of the success or failure of comparable projects. Hig h rankings to projects that are comparable to successful projects, low rankings to projects comparable with f ailed efforts, and neutral rankings to projects lacking comparable examples (return to the question of feasibi lity).

Consistency with ongoing resource agency work and environmental pl anning

Does the proposed project conflict with any ongoing resource agency work or environmental planning? Projects without conflicts, which mesh well with ongoing project s and policy, will receive the highest rankings. Projects that are inconsistent with current envir onment policy and ongoing projects will receive a lower ranking (see also “Basic need or justification for project” a nd “Legal hurdles”).

Legal hurdles (permitting, etc.)

In this category, projects that face significant legal hurdles, such as t hose that require extensive permitting for their implementation, will receive lower ranking than those projects not hindered by such requirements. The cost of overcoming these hurdles (time and money ) should also be incorporated into the evaluation of the project in other categories (“Implementat ion cost”, “Time before benefits accrue”, and “Basic need or justification for project”). Providing additiona l funding for an ongoing project, that has already passed these hurdles, would also receive a high ranking.

Implementation costs

This category is fairly straightforward but requires some additional information about the magnitude of the IM&E impacts to be offset for a proper evaluation of any poten tial project. The environmental benefits accrued by a given project need to be weighed against the impacts that need to be offset (“Cost / Benefit”).

Funding opportunities (matching funds, leveraging of funds, etc.)

Ongoing projects will do well in this category since they are already receiving at least some funding. Many potential restoration projects have popular support which can help with additional funding as well as lending support in categories like “Basic need or justifi cation for the project”, “Stake holder support”, and even “Legal hurdles”. Newer, more innovative, projects ma y have fewer funding opportunities and

would rank lower.

Ability to measure performance

Can the beneficial environmental effects of the proposed projec t be measured in some fashion that relates to offsetting the impacts of the operation of the facility in que stion? Projects with more qualitative, less tangible benefits would score lower in this ranking. Certain pro jects lend themselves more easily to this category than others. The restocking of an area with fish can r eadily be assessed by noting the number of fish introduced, the number surviving, the number reproducing, etc. Artifici al reefs and restored kelp beds can be surveyed to record species recruitment and the associat ed increase in biomass. Restored wetlands may be more difficult to assess because of their complexity, inc luding terrestrial and aquatic habitats, nursery areas, birds, mammals, fish, and invertebrates, transient species, etc. The performance of projects

that restore watershed areas is even more difficult to assess because of the indirect nature of many of their benefits to the areas directly impacted by IM&E losses.Attachment B An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

10 Cost / Benefit

How much bang-for-the-buck can be hard to gauge for many projects. The c ost may be relatively easy to calculate, but how do you measure all of the benefits of a project like the restoration of a historic wetland (see “Ability to measure performance”)? Ranking in this ca tegory may be somewhat subjective with both the cost and benefits of a project placed somewhere along a gradient tha t ranges from small to large.

Administrative considerations

How large are the administrative needs of a potential projec t. This includes taking the project through any required approval/permitting process, implementing the project, and administering it through to completion. Projects with limited need for oversight would score higher than projects requiring a large

administrative infrastructure.

Using a five point ranking system, each of the projects descr ibed in Section 3 was scored for the criteria listed above. A ranking of 1 represents a very poor fit in any ca tegory; 5 an excellent fit. As an example, a project located in Alamitos Bay, in very close proximity to HnGS, would be ranked 5 for its Location, but if it faced significant issues concerning regulatory permit ting for the project, it might rank a 2 for Legal Hurdles.

Rankings for the individual projects are shown in Table 1. No rank ings are provided for Implementation Costs or Cost Effectiveness at this time, since the magnitude and duration of the projects will be dependent upon the results of the LADWP IM&E studies.

An additional aspect not considered in the criterion of ‘Opportuni ties for leveraging of funds/Availability of matching funds’ is the potential for restoration costs to be s hared among the power generating facilities located on the coast in Santa Monica Bay or in the larger Los Angeles Basin coastal area. This would increase the scores for wetland projects in Orange County area that are closer to the power generating facilities located in the Los Angeles/Long Beach Harbor Area and fac ilities further south.

3.5.1 Results of Initial Rankings

The results of the initial ranking of projects indicate tha t the larger wetlands restoration, kelp bed restoration and artificial reef projects would be the most suit able for further evaluation. The projects with the highest ranking were the Ballona Wetlands, the Bolsa Chica Lowlands, and the Huntington Beach Wetlands projects. Although located almost 24 miles from HnGS, t he Ballona Wetlands project scored highly because it is located only 4 miles upcoast of another LAD WP power plant, SGS, and is the only remaining large coastal wetland in Los Angeles County. In contra st, the Los Cerritos Wetlands, located immediately adjacent to HnGS, did not score as high because of multiple zoning issues and the presence of large quantities of hazardous materials that were disposed in the area in the past. These projects, or other wetland projects, could be combined with one of the open coastal pro jects such as the establishment of an artificial reef to provide restoration credits for both estuarine and coastal species.Attachment BAn Addendum To The 316(B) Evaluation Of The Haynes Generating StationTABLEB-1.QUALITATIVE RANKING,WITH1BEING LOWEST AND5BEING HIGHEST,OF POTENTIAL RESTORATIONPROJECTS FOR OFFSETTINGHAYNESGENERATINGSTATIONIM&ELOSSES.RESTORATION PROJECTZUMAWETLANDSMALIBULAGOONTOPANGALAGOON ANDCREEKBALLONAWETLANDSLOSCERRITOSWETLANDSBOLSA CHICALOWLANDSHUNTINGTONBEACHWETLANDSUPPERNEWPORTBAYLASVIRGENESCREEKNON-NATIVEPLANTERADICATIONSANTA MONICABAY ROCKYINTERTIDALSANTAMONICA BAYKELP BEDSARTIFICIALREEFRESTOCKINGIMPACTEDFISH SPECIESEVALUATION CRITERIALocation4 4 4 4 5 5 5 4 3 3 5 5 5 4Nexus to HnGS Impacts4 4 4 5 4 4 4 4 3 3 3 5 5 5Basic Need or Justification ForProject2 4 3 5 4 5 5 5 3 3 3 4 3 4Nature and Extent of EcologicalBenefits2 3 2 5 4 4 4 4 2 2 3 5 5 4Stakeholder Acceptance5 5 5 5 5 5 5 5 5 5 5 5 4 5Administrative Considerations4 4 4 4 3 4 4 4 4 4 2 3 2 4Consistency With OngoingResource Agency Work andEnvironmental Planning5 5 5 5 5 5 5 5 5 5 4 5 4 3Implementation Costs No Data No Data No Data No Data NoData No Data No Data No Data No Data No Data No Data No Data No Data No DataCost Effectiveness No Data No Data No Data No Data No Data No Data No Data No Data No Data No Data No Data No DataNo Data No DataAbility to Measure Performance3 3 3 4 4 4 4 4 2 2 2 3 5 4Success of Comparable Projects3 3 3 4 4 4 4 4 3 3 2 3 5 3Time Before Benefits Accrue3 3 3 3 3 3 3 3 2 2 2 4 4 4Technical Feasibility3 3 3 4 3 4 4 4 3 3 2 3 5 3Funding Opportunities(matching funds, leveraging offunds)4 4 4 4 4 4 4 4 4 4 4 4 3 3Legal Hurdles (permitting, etc.)4 4 4 4 3 4 4 4 4 4 3 4 2 4Duration of Benefits3 3 3 5 5 5 5 5 3 3 3 3 5 3TOTAL49 52 50 61 56 60 60 59 46 46 43 56 57 53Attachment B An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

12 

## 4.0 CONCLUSIONS AND RECOMMENDATIONS

An initial screening of potential projects in the vicinity of the LADWP power plants using the set of criteria described in this report was used to determine that wetlands restoration, kelp bed restoration and artificial reef projects would be the most suitable for further evaluation. Restoration projects associated with the Ballona Wetlands, Bolsa Chica Lowlands and Huntington Beach Wetlands received the highest rankings using the criteria previously described. Although located almost 24 miles upcoast of HnGS, the Ballona Wetlands scored highly because they are located only 4 miles upcoast from the another LADWP facility, SGS, and they are the only remaining large coastal w etlands in Los Angeles County. There are active groups involved with the preservation of the wetlands and acquis ition of additional lands to expand the wetlands to its historical boundaries. These groups and project s associated with the Ballona Wetlands provide opportunities for funding similar to the approach used at E lkhorn Slough for the Moss Landing Power Plant where money was transferred to the Elkhorn Slough Foundat ion for the expansion and preservation of wetland habitat that offset entrainment losses from t he power plant.

The proposed restoration of the Los Cerritos Wetlands adjacen t to the HnGS, has the potential to be a viable restoration option for any or all of the LADWP facili ties. However, as cited in the final report of the City of Long Beach, Los Cerritos Wetlands Study Group (avail able as a downloadable pdf file at http://www.longbeach.gov/plan/pb/cpd/los_cerritos.asp ), there are several pressing issues that need to be dealt with prior to proceeding with any of the proposed restoration pr ojects. These issues include the numerous and varied zoning and jurisdictional concerns related to the area of the former wetlands, and the area’s history of use as a hazardous waste disposal site. Thes e concerns were reflected in the lower ranking of this restoration option in comparison with the Ballona Wetlands

.

A major wetlands restoration project at a location like the Ballona Wetlands could be supplemented with a coastal project to compensate for losses to marine coasta l fishes. The projects that received the highest ranking using the criteria in this report were kelp ked restor ation and artificial reefs. The San Onofre Nuclear Generating Station (SONGS) is using an artificial reef as mitigation for the effects of the thermal discharge on kelp beds and associated communities. Studies at a pilot sca le artificial reef being used in the design of the final full-scale project show that the artifici al reef is performing similar to natural reefs in the area. Development of giant kelp (Macrocystis spp.) on an arti ficial reef would provide the added benefit of increasing the area of kelp habitat, an important ha bitat-forming community in the nearshore areas at the north and south headlands of Santa Monica Bay. Kelp beds provide habitat for a wide variety of invertebrates and fishes. An artificial reef project in Santa Monica Bay benefits from all of the work that has been completed for the SONGS reef project. It is also relatively easy to demonstrate the benefits from an artificial reef, since the SONGS project has shown that communities develop fairly rapidly on the

new habitat.Attachment C An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

13 

## ATTACHMENT C -

FLOW CALCULATIONS

The following is a summary of HnGS flow calculations.

Data: Flow (Q): 1,497 cfs (Units 1,2,5,6 and 8) Water Elevation (Mean Low Water): El. -2.7 feet Number of Trash Rack Openings: 7 (only 6 in use) Area of Each Intake Opening: 175.0 feet 2 (3.5 feet by 50 feet openings) Number of Intake Pipes: 7 (only 6 in use) Area of Each Intake Pipe: 50.3 feet 2 (8 feet diameter pipes)

Invert of Intake Canal: El. -19.0 feet

Bottom Width of Intake Canal: 30.0 feet Side Slope: 2.5 H to 1 V

Formulas Used

CalculationsAttachment D An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

1 

## ATTACHMENT D -

FISH MORPHPMETRY AND SCREEN MESH HEADLOSS

The following information on fish morphometry was developed by LMS as part of a NJPDES Permit special condition for PSEG Services Corporation’s Salem Generating St ation 6

.

This study was designed to use physical measurements from preser ved ichthyoplankton to compute the expected size of larval fish retained by plankton nets of vari ous mesh sizes. “... Expectations of the size of organisms to be retained by a given mesh size can be develop ed from the physical dimensions of the organism. This may be done by first relating the greatest cross-sectional d imension (such as skull width or other measures of body girth) to overall fish length. Then, the g reatest mesh dimension is computed, typically the mesh diagonal. Smith et al. (1968) found that the maximum cross-sectional diameter of the organism must be greater than the mesh diagonal if it is to be f ully retained. For a given cross-sectional diameter and associated standard deviation, the percentage reta ined and excluded is calculated by integration under a normal curve. Examples of this type of analy sis may be seen in Vannucci (1968), Lenarz (1972), Colton et al. (1980), Turnpenny (1981), Schneeberger and Jude (1981) among others. Results of this analysis may then be used to develop working guideli nes for the minimum size necessary for retention of each species....” The only exception is the data for naked goby which were developed from scale-drawings by Alden using the LMS model. The reported en trainment and impingement probabilities are for 0.5 mm mesh screens and are provided as a n illustration of the effect of length/HCD on entrainment and impingement. The reported HCD at body length was used to predict the HCD for HnGS species. The series 3 and 4 categories refer to entrainment and impi ngement, respectively.

The screen mesh/headloss assessment was prepared by Alden wit h data provided by Johnson Screens and

Siemens Screens.

6 Public Service Enterprise Group. (2002). Salem Ge nerating Station, NJPDES Permit #NJ0005622, Custom Requirement G.9.b.ii, Entrainment Extrusion Study, Task #1, Morphometric Analysis.Attachment D An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

2 Atlantic Silverside

Eggs:

Probability Probability Entrainment Impingement

0.00000000 1.00000000

Larvae

length ln(length) ln(HCD) HCD Probability Probabili ty (mm) (mm) Entrainment Impingement

1 0 -2.17238 0.113907 1 0

2 0.6931472 -1.47022 0.229876 1 1.9867E-12

3 1.0986123 -1.05948 0.346636 0.99946385 0.00053615

4 1.3862944 -0.76806 0.463913 0.74820565 0.25179435

5 1.6094379 -0.54201 0.581576 0.08860428 0.91139572

6 1.7917595 -0.35732 0.699547 0.00135686 0.99864314

7 1.9459101 -0.20117 0.817775 5.5983E-06 0.9999944

8 2.0794415 -0.0659 0.936224 1.0692E-08 0.99999999

9 2.1972246 0.053413 1.054866 1.3169E-11 1

10 2.3025851 0.160144 1.17368 1.2815E-14 1

11 2.3978953 0.256693 1.292648 1.1191E-17 1Attachment D An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

3 Atlantic croaker

Eggs:

Probability Probability

Entrainment Impingement

0.00354797 0.99645203

Larvae

length ln(length) ln(HCD) HCD Probability Probabili ty (mm) (mm) Entrainment Impingement

1 0 -1.9015 0.149345 1 0

2 0.6931472 -1.1023 0.332107 1 4.5773E-12

3 1.0986123 -0.6348 0.530043 0.16540446 0.83459554

4 1.3862944 -0.3031 0.738525 3.9953E-11 1Attachment D An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

4 Bay anchovy

Eggs:

Probability Probability Entrainment Impingement

0.00007334 0.99992666

Larvae

length ln(length) ln(HCD) HCD Probability Probabili ty (mm) (mm) Entrainment Impingement

1 0 -1.69755 0.183132 1 3.5926E-10

2 0.6931472 -1.2165 0.296265 0.99933809 0.00066191

3 1.0986123 -0.93511 0.392543 0.9311524 0.0688476

4 1.3862944 -0.73546 0.479286 0.60240373 0.39759627

5 1.6094379 -0.5806 0.559565 0.24494069 0.75505931

6 1.7917595 -0.45406 0.635041 0.07122037 0.92877963

7 1.9459101 -0.34708 0.706746 0.01687337 0.98312663

8 2.0794415 -0.25441 0.775371 0.00355533 0.99644467

9 2.1972246 -0.17267 0.841413 0.00070377 0.99929623

10 2.3025851 -0.09955 0.905243 0.00013543 0.99986457

11 2.3978953 -0.03341 0.967145 2.5885E-05 0.99997411

12 2.4849066 0.026979 1.027346 4.982E-06 0.99999502

13 2.5649494 0.152558 1.16481 1.0607E-07 0.99999989

14 2.6390573 0.281506 1.325124 1.1194E-09 1

15 2.7080502 0.401553 1.494144 9.342E-12 1

16 2.7725887 0.51385 1.671716 6.5628E-14 1

17 2.8332133 0.619337 1.857696 4.0709E-16 1

18 2.8903718 0.718793 2.051955 2.3135E-18 1Attachment D An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

5 Atlantic menhaden

Eggs:

Probability Probability Entrainment Impingement

0.00000000 1.00000000

Larvae

length ln(length) ln(HCD) HCD Probability Probabili ty (mm) (mm) Entrainment Impingement

1 0 -0.46918 0.625518 0.03208407 0.96791593

2 0.6931472 -0.18776 0.828816 1.4783E-05 0.99998522

3 1.0986123 -0.02314 0.977127 1.5362E-08 0.99999998

4 1.3862944 0.093661 1.098187 3.9487E-11 1

5 1.6094379 0.184257 1.202325 2.0644E-13 1

6 1.7917595 0.258279 1.2947 1.8748E-15 1

7 1.9459101 0.320865 1.378319 2.6405E-17 1Attachment D An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

6 Naked goby

Eggs:

Probability Probability Entrainment Impingement

0.00000000 1.00000000

Larvae

length ln(length) ln(HCD) HCD Probability Probabili ty (mm) (mm) Entrainment Impingement

1 0 -1.40758 0.244734 1 1.5477E-13

2 0.6931472 -0.82465 0.43839 0.9101756 0.0898244

3 1.0986123 -0.48365 0.616528 0.01626992 0.98373008

4 1.3862944 -0.24171 0.785284 2.0475E-06 0.99999795

5 1.6094379 -0.05405 0.947388 3.4819E-11 1

6 1.7917595 0.099286 1.104382 3.0815E-16 1

7 1.9459101 0.228926 1.25725 2.5064E-21 1Attachment D An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

7 Wire-mesh screen head loss characteristics

Assumptions for head loss calculations:

Screen approach velocity at 1 feet/sec Through-flow screen (two screen mesh baskets in flo w path) Head loss coefficients from M. Papworth 1972

Screen characteristics:

Screen
Mesh Wire

spacing (in) Wire

dia. (in) Wire

dia. (mm) opening

(mm) Open

area Backup

screen (1" mesh) combined

open areawith 1" backup screen

3/8" mesh 0.444 0.08 2.0 9.3 67% no 67%

10 mesh 0.100 0.025 0.64 1.9 56% yes 45%

18 mesh 0.056 0.017 0.43 1.0 48% yes 39%

30 mesh 0.033 0.012 0.30 0.5 41% yes 33%

50 mesh 0.020 0.009 0.23 0.3 30% yes 24%

70 mesh 0.014 0.0065 0.17 0.2 30% yes 24%Attachment D An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

8 LITERATURE CITED

Colton, J.B., Jr., J.R. Green, R.R. Byron, and J.L. Frisella. 1980. Bongo net retention rates as effected by towing speed and mesh size. Can. J. Fish. Aquat. Sci. 37:606-623.

Lenarz, W.H. 1972. Mesh retention of Sardinops caerulea and Engraulis mordax by plankton nets. Fish.

Bull. U.S. 70:839-848.

Schneeberger, P.J. and D. J. Jude. 1981. Use of fish larva morphometry to predict exclusion capabilities of small-mesh screens at cooling-water intakes. Trans. A mer. Fish. Soc. 110:246-252.

Smith, P.E., R.C. Counts, and R.I. Clutter. 1968. Changes in filtering efficiency of plankton nets due to clogging under tow. J. Cons. perm. int. Explor. Mer.32: 232-248.

Turnpenny, A.W.H. 1981. An analysis of mesh sizes required for screening fishes at water inta kes. Estuaries, 4(4):363-368.

Vannucci, M. 1968. Loss of organisms through the meshes. In D.J. Tranter (ed.), Part I, Review on zooplankton sampling methods, p. 77-86. UNESCO Monograph. Oceanography. Methodology. 2, Zooplankton SamplingAttachment E An Addendum To The 316(B) Evaluation Of The Haynes Gener ating Station

1 

## ATTACHMENT E -

POTENTIAL FISH RETURN CLEANING SYSTEMS

Fish and debris removed from either coarse- or fine-mesh trave ling water screens would have to be conveyed back to the ocean outside of Long Beach Harbor through a 12,000 feet long return pipe. This return location was selected as returning fish to the discharge canal is expected to increase mortality due to thermal stress. Once removed from the screens, fish and debr is would flow into an open trough that would run the length of the intake canal from Unit 6 through Unit 1. Water would need to be a dded to the trough upstream Unit 6 to provide the fish removed from the Unit 6 s creens a 6 inch water cushion. Downstream of the Unit 1 screens, the return trough would flow into a small sump where a fish-friendly pump would provide the head required to create a 4 feet/sec velocit y in the return pipe. The return pipe would be a 1.5 feet diameter smooth-walled pipe. A closed pipe was selected to prevent predation from birds and other animals and allow the pipe to be placed on grade. Within the tidal area, the pipe would transition back into an open trough to allow, a smooth transition back to the ocean while allowing access to the portion of the return that cannot be isolated.

Cleaning of the trough both near the screens and within the tidal a rea would be fairly easy and could be conducted by plant personal using either brushes or a high-pressure spray. Alden has identified two options for cleaning the pipe portion. These options are: a heat treatment or two return pipes which would be used on an alternating basis to allow drying of the pipes. T he constraints and benefits of each option are listed in the following table.

Criteria Heat Treatment Two Pipes

Construction Concerns One of the existing discharge lines would need to be tapped. A pump would be required to transport water back to the
intake. Twice as much pipe with isolation
valves.

Construction Impacts on Plant Operation Would require a unit to be shutdown while the discharge is tapped. Could be completed during a scheduled outage. None.

Impacts on Plant Operation Heat treatments would ne ed to
be timed to coincide when units are operating at maximum inlet temperature and plant output. None.

Impacts on Screen Operation None. None. Impacts on Survival No survival during heat

treatment. None.

Reliability If return pipe or hot water line fails there is no redundancy. If one return pipe fails the second one can be brought into operation rapidly.

Installation Cost 1 $2,480,000 $3,625,000

O&M Costs 1 $35,000 $35,000

1. Costs are in 2006 and are based on the same assumpt ions as the costs in the cost section of this Adden dum

The same methods used to clean the fish return for the modified tr aveling screen options would be applicable to the fish return required for Modular Included Sc reens. The fish return pipe for the MIS would be about half the length of the traveling screen return but would require a larger pipe, about 4 feet diameter, to accommodate the required bypass flow. The preceding table is valid for MIS return, except for the costs. For the MIS return system the cost for both cl eaning options would be very similar as the length of the heat treat pipe would be about the same length as the second return pi pe.Attachment F An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

1 

## ATTACHMENT F -

NARROW -SLOT, WEDGEWIRE SCREEN CONCEPTUAL DESIGN

Narrow-slot wedgewire screens could be installed in the intake canal at HnGS. To function effectively, an “ambient” flow past the screens would be needed to remove impinged fish and de bris from the screens. To create this ambient flow, “fish friendly” bypass pumps locat ed at the terminus of the canal would be used. The following discussion relates to existing conditions a nd does not take into account the Units 5 and 6 re-powering potentials.

Conceptual Design

The screens would be installed on a bulkhead wall located in the ex isting intake canal as shown on Figure F-1. The bulkhead would partition off about half of the intake cana l, extending from approximately 150 feet upstream of the Unit 1 CWIS to the terminus of the canal. This partition would isolate the flow through the wedgewire screens from the flow heading to the bypass pum ps. The bulkhead would consist of sheetpile walls, steel support piles, and a 12 feet wide pla tform extending the length of the bulkhead. The top of the bulkhead wall and platform would be at El. 8.0 feet. A new pumphouse would be constructed for the pumps that would provide the ambient flow past the scree ns.

The screens would have a 0.5 mm slot size and would be designed for a maximum slot velocity of 0.5

feet/sec. A narrower slot size was not evaluated as 0.5 m m is the finest slot size currently available for cylindrical wedgewire screens at cooling water intake struc tures. Fifty-six T-84 screens would be required for total plant flow, a breakdown of the number of scre ens required be unit is provided in Table F-1. Each screen would be 7.0 feet in diameter and T-shaped, wi th an overall length of about 23.0 feet. Two screen sections, each about 8.0 feet long, would be located on ea ch side of a 7.0 feet long T section. The outlet pipe would be 5.0 feet in diameter and located in the middle of the T section. The outlet of the T would be flanged for connection to a 5.0 feet diameter intak e pipe. The screens would be installed in two rows. The centerline of the rows will be 21.0 feet apart , providing two diameters of clear spacing

between screens. A sectional view of the screens in the intake canal is shown in Figure F-2. The upstream end of the screen cylinders would be tapered to deflect subm erged floating debris. A typical section of a wedge wire screen is shown on Figure F-3.

Currently, the flow in the intake canal is a result if the circulating water withdrawal. This flow does create a bypass flow for the upstream-most units; however, the fish and debris that bypass these units would be impinged or entrained through the latter units. To remedy thi s, additional flow needs to be added to the intake canal. A minimum bypass velocity of about 1.0 f eet/sec at the last screen is recommended by Alden to transport fish and debris from the screens. To reduce the amount of bypass flow needed a second bulkhead wall would be installed along the south side of the intake canal. This wall will be angled into the canal to decrease the cross-sectional area. A bypass flow of about 700 cfs would be needed to create a 1.0 feet/sec velocity at the end of the canal . This flow will be created by (6) 450 hp, Hidrostal pumps located in a small intake located at the terminus of the i ntake canal. Hidrostal pumps use a fish friendly screw impellor that can pump fish and debris wi thout causing damage, typically associated with pumps. To prevent large debris from damaging the pumps a trash ra ck would be installed at the face of the structure. This bypass flow would allow use of an air back wash system to remove debris from the screens. The air backwash system would be fully automated, and i nclude all necessary air compressors and controls. Air compressors, air receivers and controls would be located in a new pump house or near the new bulkhead. Air piping for each wedgewire screen would be i nstalled under the platform walkway and run along the top of the intake pipes to each screen. In additi on to the air backwash, periodic manual cleaning for removal of biofouling may be necessary.

After passing through the bypass pumps, fish and debris will be conveye d through a 12.0 feet diameter discharge pipe to either the San Gabriel River (plant-side) or directly back to the ocean. The velocity within the pipe would be about 6.2 feet/sec which should be sufficie nt to prevent large organisms from holding within the pipe. Fouling in the return pipe could be an is sue. To reduce the potential for fouling,Attachment F An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

2 the walls of the pipe would be treated with an anti-fouling epoxy c oating. A return pipe to the San Gabriel River would be about 1,000 feet long. Discharging to the S an Gabriel River may result in the increased mortality due to increased thermal stress, as the ri ver is used by both HnGS and Alamitos as a discharge canal.

Engineering Considerations

Approach velocities at the wedgewire screens would be 1.0 feet/se c or greater at normal water levels (El. 0.0 feet) and full plant operations. The estimated velocities in the canal under these conditions are provided in Table F-2. The velocities in the canal during both low a nd high water are also provided in this table. When the water in the canal is high, the velocit y approaching the last screen would be about 0.9 feet/sec which should be sufficient to transport debris away fr om the screens. Assuming fairly uniform flow through each screen, the maximum through-screen vel ocity would not exceed 0.5 feet/sec. Headloss through the screens should not exceed one foot (assuming biofouling would not be a significant problem). Except for the slightly lower water level, flow c haracteristics between the bulkhead and CWISs with the wedgewire screens would not be any different tha n the existing intake. Flow patterns to the pumps would not change from the existing conditions.

Installing wedgewire screens in this manner is atypical and wou ld require hydraulic model studies (numeric and/or physical) to determine the optimum layout of the screens and the effectiveness of the sweeping current. Cost for these studies have not been included but could range from about $20,000 for a simple two-dimensional numeric study up to about $200,000 for both three-dim ensional numeric and physical models.

Construction Considerations

Installation of the new wedgewire units and modifications to the existing intake structure would be accomplished over a two-year period and would be sequenced to minimiz e impacts on plant operation. The bulkhead wall and platform would be installed first. The upstre am end of the bulkhead and all the intake pipe openings would remain open to allow continued plant opera tion. Construction of the fish return pipe would occur simultaneously to the bulkhead installa tion since two years would be needed to complete if the return pipe back to the ocean. After completion of the bulkhead walls, a cofferdam would be constructed just upstream of the terminus of the canal to all ow the bypass structure to be constructed for the bypass pumps. The air-burst control systems and piping would also be installed at this time. Once the bypass pumps and return system are operational, the wedgewire screens, cleaning system and remaining bulkhead walls would be installed. During this stage, whic h is expected to take about 2 months, the facility would need to be shutdown.

Operation and Maintenance Considerations

Operation and maintenance (O&M) of the screens would eliminate ope ration and maintenance on the existing traveling water screens. Maintenance requirements for the circulating water pumps with the wedgewire screens in place would not change. An air-burst sys tem would be used to clean the screens. For this evaluation, Alden assumes that the screens would need t o be cleaned three times a day; the actual number will vary depending on the debris loading in the canal. F ive, 150-hp air compressors operating 9 hours a day would be necessary to air-burst the screens. Operating the air compressors would require 1,848,000 kWh per year and about 1,095 man-hours per year to monitor backwashing ope ration and to maintain the air supply equipment. In addition, the screens would requi re a bi-annual inspection to identify any damage that could affect plant operations and to verify effec tive cleaning by the air backwash system. During the inspection, each screen would be manually cleane d, if necessary. Each inspection and cleaning would take approximately one week using divers working in the can al.

The fish bypass system would require extensive O&M effort. Eac h bypass pump would require a 450 Hp motor and need 16,281,000 kWh per year to operate. Additionally, about 1 hour per day would be needed to remove any debris from the bypass pump trash racks and to inspec t the pumps. The total O&MAttachment F An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

3 associated with the wedgewire system in the canal would requir e about 18,129 MWh per year and 1,880 man-hours. Depending on the return system selected, the man-hours re quired to clean the pipes would be about 484 hours for the 1,000 feet long pipe up to 6,084 for the 15,000 feet l ong pipe. Energy requirements to clean either return pipe would be negligible; howe ver, HnGS would need to be shutdown during the cleaning to allow the pipe to be de-watered.

Costs

Order-of-magnitude project costs were developed for this alte rnative. The costs for the two potential return pipes are included as separate items. The costs were estimated using quantities developed from the conceptual design and cost data from other projects that were ad justed for identifiable differences in project sizes and operations. These costs allow LADWP to com pare the costs for this option with that of other potential compliance options at HnGS.

The estimated costs are based on the following:

• Present-day prices and fully contracted labor rates as of January 1, 2007.

• Forty-hour work week with single-shift operation for construction ac tivities that do not impact plant operations and fifty-hour work week with double-shift operation for construction activities that impact plant operations.

• Direct costs for material and labor required for construction of all project features. The direct costs also include distributable costs for site non-manual supervi sion, temporary facilities, equipment rental, and support services incurred during construction. These c osts have been taken as 85% of the labor portion of the direct costs for each alternative.

• Indirect costs for labor and related expenses for engineering ser vices to prepare drawings, specifications, and design documents. The indirect costs have been t aken as 10% of the direct

costs for each alternative.

• Allowance for indeterminates to cover uncertainties in design and construction at this preliminary stage of study. An allowance for indeterminates is a judgment factor that is added to estimated figures to complete the final cost estimate, while still a llowing for other uncertainties in the data used in developing these estimates. The allowance for indetermina tes has been taken as 10% of the direct, distributable, and indirect costs of each alternative.

• Contingency factor to account for possible additional costs that might develop but cannot be predetermined (e.g., labor difficulties, delivery delays, weather). The c ontingency factor has been taken as 15% of the direct, distributable, indirect, and allowan ce for indeterminate costs of each

concept.

• Replacement power costs

The project costs do not include the following items that should be included to obtain total capital cost

estimates:

• Costs to perform additional laboratory or field studies that may be required, such as hydraulic model studies, biological evaluations of prototype fish protecti on systems, soil sampling, and wetlands delineation and mitigation.

• Costs to dispose of any hazardous or non-hazardous materials that may be encountered during excavation and dredging activities.

• LADWP costs for administration of project contracts and for engi neering and construction

management.

• Price escalationAttachment F An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

4 • Permitting costs

The estimated project costs for the wedgewire screens and th e two return options are presented in Table F-3 through Table F-5.

The annualized costs associated with each of the return options are presented in Table F-6. To annualize the costs, several assumptions were made:

• The capital costs were annualized over 10 years

• A 7% discount rate was used

• The cost per MWh is $50.00

Alden included an estimate of existing annual O&M costs to allow i ncremental costs to be calculated. The exiting O&M costs were estimated using the same assumption s as used in calculating the O&M costs for the selected technologies. Incremental costs provide a better estim ate of the additional cost that would be required.

The cost for wedgewire screens with either of the return s ystems can be calculated by adding the costs of wedgewire to the return costs. The incremental annual cost f or wedgewire screens is $17,521,000 for the 1,000 feet long return and $ 32,529,000 for the 15,000 feet long return.Attachment F An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

5 F IGURE F-1. L AYOUT OF C YLINDRICAL W EDGEWIRE S CREENS IN THE I NTAKE C ANALAttachment FAn Addendum To The 316(B) Evaluation Of The Haynes Generating Station6FIGUREF-2.SECTION OFCYLINDRICALWEDGEWIRESCREENS IN THEINTAKECANALAttachment FAn Addendum To The 316(B) Evaluation Of The Haynes Generating Station7FIGUREF-3.TYPICALWEDGEWIRESCREEN ATHNGSAttachment F An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

8 T ABLE F-1. N UMBER OF C YLINDRICAL W EDGEWIRE S CREENS R EQUIRED FOR E ACH U NIT

Intake T-84 Screens Needed

Unit 1 8

Unit 2 8

Unit 8a 7

Unit 8b 7

Unit 5 13

Unit 6 13

Total 56

T ABLE F-2. V ELOCITIES IN THE I NTAKE C ANAL WITH THE F ISH B YPASS S YSTEM AT D IFFERENT W ATER L EVELS

.

Location Flow (cfs) Extreme Low Water (El. - 6.0 feet) Mean Low

Water (El. - 2.7 feet) MSL (El. 0.0

feet) High Water

(El. 3.0 feet) Upstream of Intakes 2197.2 3.3 2.4 2.0 1.6

less 1 1983.3 3.0 2.2 1.8 1.4

less 2 1769.4 2.7 2.0 1.6 1.3

less 8a 1591.2 2.4 1.8 1.4 1.2

less 8b 1413.0 2.1 1.6 1.3 1.0

less 5 1056.5 2.3 1.9 1.6 1.4

less 6 700.0 1.5 1.2 1.1 0.9 Bypass only 1 700.0 1.05 0.8 0.6 0.5 1. Just upstream of Unit 1 with only the bypass pum ps in operation.Attachment F An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

9 T ABLE F-3. E STIMATED C OSTS FOR 0.5 MM W EDGEWIRE S CREENS

Item Estimated Cost

Direct Costs

Mobilization and Demobilization $2,569,000

Bulkhead Wall $4,027,000

Bulkhead Deck $4,468,000

Intake pipes & supports $643,000

Wedgewire Screens $3,902,000

Bypass intake $434,000

Bypass Pumps and Pipes $3,520,000

Air-burst Cleaning System $2,000,000

Cranes, Barges and Equipment $6,691,000

Direct Costs (2007 $) $28,254,000

Indirect Costs 2,825,000

Subtotal $31,079,000

Allowance for Indeterminates/Contingencies 7,770,00 0

Total Estimated Project Costs (2007 $) $38,849,000

Impacts on Plant Operation

Item Impact

Construction

Duration (months) 24

Outage (months) 2

Incremental Annual Operation and Maintenance

Labor, (hrs) 1,880

Component Replacement $65,000

Energy (kwh) 18,129,000

Peak Power (kw) 2,138Attachment F An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

10 T ABLE F-4. E STIMATED C OSTS A 1,000 FEET R ETURN P IPE

Item Estimated Cost

Direct Costs

Mobilization and Demobilization $254,000

Discharge Pipe $2,184,000

Discharge Structure $341,000

Isolation gate $16,000

Barges, Divers and Equipment $0

Direct Costs (2007 $) $2,795,000

Indirect Costs $279,500

Subtotal $3,075,000

Allowance for Indeterminates/Contingencies $769,000

Total Estimated Project Costs (2007 $) $3,844,000

Impacts on Plant Operation

Item Impact

Construction
Duration (months) 6

Outage (months) 0

Incremental Annual Operation and Maintenance

Labor, (hrs) 484

Component Replacement $0

Energy (kwh) 1 147,000

Peak Power (kw) 0 1. Energy is replacement power needed when the faci lity is shutdown to clean the discharge pipeAttachment F An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

11 T ABLE F-5. E STIMATED C OSTS FOR A 15,000 FEET R ETURN P IPE

Item Estimated Cost

Direct Costs

Mobilization and Demobilization $3,311,000

Discharge Pipe $32,755,000

Discharge Structure $341,000

Isolation gate $16,000

Barges, Divers and Equipment $0

Direct Costs (2007 $) $36,423,000

Indirect Costs $3,642,300

Subtotal $40,065,000

Allowance for Indeterminates/Contingencies $10,016, 000

Total Estimated Project Costs (2007 $) $50,081,000

Impacts on Plant Operation

Item Impact

Construction

Duration (months) 24

Outage (months) 0

Incremental Annual Operation and Maintenance

Labor, (hrs) 6,084

Component Replacement $0

Energy (kwh) 1 311,000

Peak Power (kw) 0

1. Energy is replacement power needed when the facilit y is shutdown to clean the discharge pipeAttachment F An Addendum To The 316(B) Evaluation Of The Haynes Gene rating Station

12 T ABLE F-6. C OST C OMPARISON OF E VALUATED A LTERNATIVES

Capital Costs Annual O&M Costs

Alternative Total Project

Construction
Costs (2007$) Replacement

Power During
Construction (MWh) Total Capital

Costs (2007 $) 1 Energy

(2007 $) 1 Labor

(2007 $) Component

Replacement (2007 $)

Narrow slot Wedge
Wire Screens and bypass structure, without a return system $38,849,000 489,000 $63,299,000 $906,000 $101,000 $ 65,000

1,000 feet long Return Pipe $3,844,000 0 $3,844,000 $7,342,000 $16,000 $0

15,000 feet long Return Pipe $50,081,000 0 $50,081,000 $15,541,000 $242,000 $0

Existing Operations 3 $0 0 0 $8,000 $175,000 $285,000

Annualized Costs Incremental Costs

Alternative Total Annual
O&M Annualized

Capital Costs (2007 $) 2 Total

Annualized
Costs (2007 $) Incremental

O&M Incremental

Annualized Costs (2007 $)

Narrow slot Wedge
Wire Screens $1,072,000 $9,012,000 $10,084,000 $604,000 $9,61 6,000

1,000 feet long Return Pipe $7,358,000 $547,000 $7,905,000 $7,358,000 $7,905 ,000

15,000 feet long Return Pipe $15,783,000 $7,130,000 $22,913,000 $15,783,000 $ 22,913,000

Existing Operations $468,000 $0 $468,000 $0 $0

1. Assumed $50 per MWh. 2. Annualized over 10 years with a 7% Discount rat e 3. Estimated by Alden