ML21280A103

Updated Biological Assessment of Impacts to Federally Listed Species Under NMFS Jurisdiction for SONGS Decommissioning

ML21280A103
Person / Time
Site:	San Onofre
Issue date:	12/06/2021
From:	Arlene B Office of Nuclear Material Safety and Safeguards
To:
Briana Arlene 301-415-1042
References
Download: ML21280A103 (69)

Text

Biological Assessment of Impacts to Federally Listed Species Under the National Marine Fisheries Services Jurisdiction San Onofre Nuclear Generating Station, Units 2 and 3 Decommissioning Under Existing Facility Operating License Nos. NPF-10 and NPF-15 September 2021 Updated December 2021 Docket Nos. 50-361 and 50-362 U.S. Nuclear Regulatory Commission Rockville, Maryland Prepared by:

Briana S. Arlene Conservation Biologist & ESA Consultation Coordinator Division of Rulemaking, Environmental, and Financial Support Office of Nuclear Material Safety and Safeguards

Table of Contents 1.0 Introduction ................................................................................................................. 1 2.0 Background/History ..................................................................................................... 2 3.0 Proposed Action .......................................................................................................... 3 4.0 Action Area.................................................................................................................. 8 5.0 Federally Listed Species ........................................................................................... 13 5.1 Guadalupe Fur Seal ........................................................................................... 14 5.1.1 Description and Life History ..................................................................... 15 5.1.2 Occurrence Within the Action Area ......................................................... 16 5.2 Whales ............................................................................................................... 16 5.2.1 Life History............................................................................................... 16 5.2.2 Blue Whale .............................................................................................. 17 5.2.3 Fin Whale ................................................................................................ 18 5.2.4 Humpback Whale .................................................................................... 19 5.2.5 Gray Whale.............................................................................................. 19 5.2.6 Occurrence Within the Action Area ......................................................... 20 5.3 Sea Turtles ......................................................................................................... 21 5.3.1 Life History............................................................................................... 21 5.3.2 Loggerhead Sea Turtle ............................................................................ 21 5.3.3 Green Sea Turtle ..................................................................................... 22 5.3.4 Leatherback Sea Turtle ........................................................................... 23 5.3.5 Olive Ridley Sea Turtle ............................................................................ 24 5.3.6 Occurrence Within the Action Area ......................................................... 25 6.0 Federally Designated Critical Habitat ........................................................................ 25 7.0 Effects of the Proposed Action .................................................................................. 25 7.1 Effects Associated with Water Withdrawal ......................................................... 26 7.2 Effects Associated with Water Discharge .......................................................... 31 7.3 Effects Associated with Removal of Offshore Structures ................................... 31 8.0 Mitigation Strategies.................................................................................................. 38 8.1 Marine Mammal and Sea Turtle Mitigation and Monitoring Plan ....................... 38 8.2 Biological Opinion Monitoring and Reporting ..................................................... 40 8.3 Other Mitigation and Monitoring Plans ............................................................... 40

- ii -

9.0 Cumulative Effects .................................................................................................... 41 10.0 Conclusions............................................................................................................. 41 10.1 Guadalupe Fur Seal ......................................................................................... 42 10.2 Blue Whale ....................................................................................................... 42 10.3 Fin Whale ......................................................................................................... 42 10.4 Humpback Whale, Central American and Mexico DPSs ................................. 42 10.5 Gray Whale, Western North Pacific DPS ......................................................... 43 10.6 Loggerhead Sea Turtle, North Pacific Ocean DPS .......................................... 43 10.7 Green Sea Turtle, East Pacific DPS ................................................................ 43 10.8 Leatherback Sea Turtle .................................................................................... 43 10.9 Olive Ridley Sea Turtle .................................................................................... 43 11.0 Relevant Reports .................................................................................................... 43 12.0 Literature Cited........................................................................................................ 45 Tables Table 1. Allowable and Actual Sea Turtle Entrainment, 2006-Present .......................... 28 Table 2. Annual Sea Turtle Entrainment Rates During Power Operations (Actual) and Decommissioning (Estimated) .......................................................... 28 Table 3. Anticipated Total Sea Turtle Entrainment During Decommissioning, June 2013-December 2025 .................................................................... 29 Table A1. Occurrences of Federally Listed Marine Species in the Action Area ............ A-4 Table A2. All Sea Turtle Entrainment, 1984-Present ................................................. A-12 Figures Figure A1. SONGS Site Layout............................................................................... A-2 Figure A2. SONGS Site Layout with Exclusion Area Boundary .............................. A-3

- iii -

Abbreviations, Acronyms, and Symbols ac acre(s)

ADAMS Agencywide Documents Access and Management System CCC California Coastal Commission CDP Coastal Development Permit CEQA California Environmental Quality Act CFR Code of Federal Regulations cm centimeter(s)

CSLC California State Lands Commission CSTSN California Sea Turtle Stranding Network D&D deactivation and decommissioning dBrms decibels Root Mean Square DECON decontamination and dismantlement Diablo Canyon Diablo Canyon Nuclear Power Plant, Units 1 and 2 DOE U.S. Department of Energy DPS distinct population segment EIR environmental impact report ESA Endangered Species Act of 1973, as amended ESPA Endangered Species Preservation Act of 1966 fps feet per second ft foot (feet) ft2 square foot (feet) ft3 cubic foot (feet)

FWS U.S. Fish and Wildlife Service g/m2 grams per square meter gpm gallons per minute ha hectare(s)

Holtec International in. inch(es)

ISFSI independent spent fuel storage installation ITS incidental take statement kg kilogram(s) km kilometer(s) lb pound(s)

LOED large organism exclusionary device LTP license termination plan m meter(s) m2 square meter(s) m3 cubic meter(s) mgd million gallons per day mi mile(s)

- iv -

MMO marine wildlife observer m/s meters per second NEPA National Environmental Policy Act of 1969, as amended NMFS National Marine Fisheries Service NPDES National Pollutant Discharge Elimination System NRC U.S. Nuclear Regulatory Commission OTC Policy Water Quality Control Policy on the Use of Coastal and Estuarine Waters for Power Plant Cooling PG&E Pacific Gas and Electric Company ppt parts per thousand PSDAR post-shutdown decommissioning activities report RPM reasonable and prudent measure SCE Southern California Edison Company SDRWQCB San Diego Regional Water Quality Control Board SDS SONGS Decommissioning Solutions SONGS San Onofre Nuclear Generating Station, Units 2 and 3 SWRCB State Water Resource Control Board T&C term and condition USACE U.S. Army Corps of Engineers

-v-

1.0 Introduction The U.S. Nuclear Regulatory Commission (NRC) staff prepared this biological assessment to comply with the provisions of Section 7 of the Endangered Species Act of 1973, as amended (ESA), in support of the NRCs request to reinitiate formal consultation with the National Marine Fisheries Service (NMFS) in connection with the shutdown and decommissioning of San Onofre Nuclear Generating Station (SONGS),

Units 2 and 3, under its existing NRC licenses, in San Clemente, California.

As explained below, reinitiation of consultation is required because the activities associated with the shutdown and decommissioning of SONGS were not considered in NMFSs 2006 biological opinion for the continued operation of SONGS. Additionally, in itsSection III, Description of the Proposed Action, that biological opinion provides that it is only valid through 2022.

This assessment evaluates the impacts of the proposed action on federally listed species and designated critical habitat under NMFSs jurisdiction. These species include several species of sea turtles, 1 whales, 2 black abalone (Haliotis cracerodii),

white abalone (H. sorenseni), California steelhead (Oncorhynchus mykiss irideus), and green sturgeon (Acipenser medirostris).

Data incorporated into and analyzed in this assessment includes all incidental takes reported at SONGS through August 31, 2021. In preparing this assessment, the NRC used the best scientific and commercial data available to evaluate the potential effects of the proposed action on federally listed species and designated critical habitat.

Prior to finalizing this assessment, the NRC staff provided Southern California Edison Company (SCE) the opportunity to review the assessment and to affirm the accuracy of the information presented herein. SCE provided comments on the assessment, which the NRC staff incorporated into the assessment, as appropriate.

In November 2021, the NRC staff updated this biological assessment to include the following:

• a more detailed description of the ocean intake system that clarifies differences between the systems use and function during SONGS power operations versus during the decommissioning period;

• descriptions of marine mammals that may occasionally or seasonally transit the action area (Guadalupe fur seal and blue, fin, humpback, and gray whales) and an assessment of the potential impacts on these species;

• corrections to numbers of historical sea turtle entrainments at SONGS; 1

These include loggerhead sea turtles (Caretta caretta), green sea turtles (Chelonia mydas),

leatherback sea turtles (Dermochelys coriacea), and olive ridley sea turtles (Lepidochelys olivacea).

2 These include blue whale (Balaenoptera musculus), sperm whale (Physeter macrocephalus), fin whale (B. physalus), humpback whale (Megaptera novaeangliae), sei whale (B. borealis), and gray whale (Eschrichtius robustus).

• an expanded assessment of the potential impacts of water withdrawal on listed species;

• an assessment of the potential impacts of water withdrawal on prey of listed species;

• an expanded discussion of the potential for release of hydrogen sulfide gas during intake conduit removal activities, the potential effects of such releases, and related mitigation; and

• consideration of the results of previous ESA Section 7 consultations between the U.S. Army Corps of Engineers (USACE) and NMFS concerning other projects at SONGS, as appropriate.

2.0 Background/History NMFS (2006) issued a biological opinion for the continued operation of SONGS on September 18, 2006. The incidental take statement (ITS) included in that opinion exempts from the prohibitions of ESA Section 9, subject to compliance with certain reasonable and prudent measures (RPMs) and terms and conditions (T&Cs), the capture or impingement of specified numbers of:

• loggerhead sea turtle,

• green sea turtle,

• leatherback sea turtle, and

• olive ridley sea turtle.

NMFSs biological opinion applies to the continued operation of SONGS under the terms of NRC Facility Operating License Nos. NPF-10 and NPF-15 issued by the NRC on February 16, 1982 (Unit 2) and November 15, 1982 (Unit 3). These licenses authorize SCE to operate SONGS through February 16, 2022 (Unit 2) and November 15, 2022 (Unit 3). However, SCE permanently ceased power operations at SONGS on June 7, 2013, and began the active decommissioning of SONGS in February 2021.

NMFSs biological opinion applies to both the continued operation of SONGS as well as the continued operation of Diablo Canyon Nuclear Power Plant, Units 1 and 2 (Diablo Canyon). Diablo Canyon is in Avila Beach, California, approximately 200 mi (320 km) northwest of SONGS. Diablo Canyon is authorized to operate under NRC Facility Operating License Nos. DPR-80 and DPR-82 issued by the NRC on November 2, 1984 (Unit 1), and August 26, 1985 (Unit 2) through November 2, 2024 (Unit 1), and August 26, 2025 (Unit 2), respectively. Pacific Gas and Electric Company (PG&E), the owner and operator of Diablo Canyon, plans to permanently cease power generation at Diablo Canyon on the license expiration date of each unit. The NRC will address the potential impacts of the shutdown and decommissioning of Diablo Canyon under its existing NRC licenses on federally listed species in a separate biological assessment.

The ESA Section 7 regulations at Title 50 of the Code of Federal Regulations (50 CFR)

Section 402.16 require Federal agencies to reinitiate consultation where discretionary Federal involvement or control over the action has been retained or is authorized by law and, among other things, the identified action is subsequently modified in a manner that causes an effect to the listed species or critical habitat that was not considered in the biological opinion or written concurrence. This biological assessment supports the NRCs request to reinitiate consultation.

3.0 Proposed Action The proposed action for the requested reinitiated consultation is the shutdown and decommissioning of SONGS under its existing NRC licenses.

SONGS is located on the Pacific coast of southern California in San Clemente in northern San Diego County. The approximate coordinates are latitude 33° 22 10 N and longitude 117° 33 30 W. The site is entirely within the boundaries of the Marine Corps Base Camp Pendleton near the northwest end of its 18-mi (29-km) shoreline. SCE obtained an easement from the U.S. Navy to build and operate SONGS on this parcel of land. The easement expires on May 11, 2024 (SCE 2016).

The SONGS site lies on the southern California coast within the Peninsular Range Province. Northwesterly trending elongate mountain ranges and valleys are characteristic of this region. The mouth of San Mateo Creek lies approximately 2 mi (3.2 km) northwest of the site. The physiography of the area is typical of the region, with a rather narrow, gently sloping, coastal plain extending seaward from the uplands. The plain terminates at the beach and forms a line of sea cliffs, which have been straightened over long distances by marine erosion. Sea cliffs in the immediate vicinity of SONGS rise to 60 to 100 ft (18 to 30 m) above sea level and are separated from the ocean by a narrow band of beach sand. In places, ephemeral streams are actively eroding gullies into the seaward portions of the coastal plain, and several deeply incised barrancas have formed. The site contains minimal natural vegetation. Sparse coastal strand vegetation occurs along the sandy beach at the base of the San Onofre bluffs.

The upload terrace supports coastal sage scrub and grasslands. (SCE 2016)

The site is approximately 4,500 ft (1372 m) long and 800 ft (244 m) wide, comprising 84 ac (34 ha). The reactors occupy 52.8 ac (21.4 ha), the power block and site switchyard cover 27.7 ac (11.2 ha), and parking, access, and miscellaneous structures occupy the remaining area. Section 3 of Enercons Environmental Impact Evaluation (Enercon 2014) contains a detailed description of the SONGS facility, its configuration, and its operation. Figure A1 in Appendix A is an aerial map of the SONGS site, and Figure A2 depicts the site layout with labels of the major facility structures and the exclusion area boundary.

The facilitys ocean water intake system withdraws water from and discharges effluent to the Pacific Ocean. During operations, this system supplied cooling water to dissipate excess heat created during power generation. Since operations have ceased, the systems cooling function is no longer required, and water withdrawal and discharge has been greatly reduced. The ocean water intake system is described below in detail in the section titled Water Withdrawal and Discharge.

Decommissioning Overview SCE has chosen a method of decommissioning called decontamination and dismantlement (DECON). Under this method, SCE will remove or decontaminate the equipment, structures, and portions of the facility that contain radioactive contaminants to a level that permits termination of the existing NRC licenses. SCE has completed the planning period and is currently performing active decommissioning. During the planning period, SCE (2020) accomplished the following:

• permanently ceased power operations on June 7, 2013;

• selected DECON method of decommissioning;

• added additional independent spent fuel storage installation (ISFSI) capacity to meet the sites needs for spent fuel storage;

• completed initial site characterization activities;

• isolated the spent fuel pools (referred to as islanding);

• completed other necessary actions to facilitate safe system abandonment and removal; and

• completed State permitting activities necessary to allow dismantlement to begin.

Additionally, SCE (2020) has completed the following activities associated with the active deactivation and decommissioning (D&D) period:

• Initial Activities (June 2013 - December 2016): SCE obtained necessary NRC license amendments and exemptions, began the expansion of the ISFSI, and procured a decommissioning general contractor, SONGS Decommissioning Solutions (SDS).

• Transition and Pool Storage (January 2017 - December 2019): SCE transitioned D&D responsibility to SDS, completed the California Environmental Quality Act (CEQA) process with California State Lands Commission (CSLC), and obtained a Coastal Development Permit (CDP) from the California Coastal Commission (CCC). Holtec International (Holtec), a separate contractor, continued with the ISFSI expansion and began transferring spent fuel from the spent fuel pools adjacent to the reactors into ISFSI dry storage.

• D&D and Pool Storage (January 2020 - December 2020): SDS abated frigid asbestos in the containments and planned segmentation and packaging of the reactor vessels and reactor internals. Holtec completed the transfer of all spent fuel from the spent fuel pools into ISFSI dry storage, and SCE sought and received amendments to the SONGS licenses that allow only the operation of the ISFSI.

The decommissioning periods that remain consist of the following (SCE 2020):

• D&D and Dry Storage (January 2021 - December 2028): SDS will decontaminate, dismantle, demolish, remove, and dispose of SONGS to approximately 3 ft (0.9 m) below grade except for the ISFSI and its associated security facilities and the switchyard area.

• Dry Storage (January 2029 - December 2045): The primary activity during this period will be the ongoing maintenance and security of the ISFSI and the transfer of all spent fuel to the U.S. Department of Energy (DOE). SCE assumes that, based on most recently available information, the DOE will begin accepting spent fuel nationally no sooner than 2028, although this date remains uncertain.

During this period, the Navy would also undertake a National Environmental Policy Act of 1969, as amended (NEPA), review associated with amending the SONGS real estate authorization to establish the site restoration or end state requirements for SCE to return the property to the Navy.

• Civil Works Projects (January 2046 - December 2049): A decommissioning general contractor would remove all onshore below-grade man-made structures except for the North Industrial Area where the ISFSI is located. Dewatering of the site to support substructure removal would begin in this phase and continue into the next phase. The DOE would complete the removal of the remaining spent fuel from the ISFSI.

• ISFSI Demolition and Final Site Restoration (January 2050 - December 2051):

SDS would dismantle and dispose of the ISFSI and complete final site restoration work, including excavation and removal of the offshore intake and outfall conduits. SCE would obtain NRC approval to terminate the remaining licenses covering the site and return the property to the Navy.

Section II of SCEs Post-Shutdown Decommissioning Activities Report (PSDAR),

Revision 1 (SCE 2020) describes SONGS decommissioning activities in more detail.

With respect to the aquatic environment, SONGS will continue to withdraw water from and discharge water to the Pacific Ocean at significantly reduced volumes for a period.

Other decommissioning activities that could affect the aquatic environment involve the removal of offshore components, including intake and discharge structure components, the fish return system, and navigational and environmental monitoring buoys, as described below.

Water Withdrawal and Discharge SONGS withdraws water from the Pacific Ocean from two offshore intake structures located approximately 3,200 ft (980 m) offshore. The intake structures are 660 ft (200 m) apart and are in water approximately 33 ft (10 m) deep.

Ocean Intake System Configuration During Operations During operations, the velocity caps at the submerged end of each intake conduit converted vertical flow to lateral flow, which triggered a flight response from motile fish to minimize entrainment. The onshore portion of each intake consisted of six vertical traveling screens fitted with 3/8-in. (0.95-cm) mesh panels. Through-screen velocity was 2.8 fps (0.85 m/s). The screens were angled at approximately 30° to incoming flow to guide fish to a quiet zone at the far end of the intake structure. A fish elevator periodically emptied captured fish into a 4-ft (1.2-m)-diameter conduit that returned fish by gravity flow to a submerged location approximately 1,900 ft (579 m) offshore. (Tetra Tech 2008)

The traveling screens automatically rotated based on pressure differential between the upstream and downstream faces of the screen, although SCE was also able to manually rotate the screens. A high-pressure spray removed debris and any aquatic organisms that were not guided to the quiet zone. Captured debris was collected in a dumpster and disposed of offsite at a landfill. (Tetra Tech 2008)

Four circulating water pumps were located downstream of the intake screens. Each pump was rated at 207,000 gpm (298 mgd), and each unit had a design pump capacity totaling 828,000 gpm (1,192 mgd) for a facility total of 1,656,000 gpm (2,384 mgd). The intake structures terminated at the plant in open air forebays. (Tetra Tech 2008)

During operations, a portion of the intake flow was used for the cooling system, which removed heat from auxiliary reactor systems and the turbine plant. Water for this system was withdrawn from and returned to the main condenser flow. (Tetra Tech 2008)

Much of the equipment described above is no longer in service. The above description is included in this assessment to support the NRC staffs analysis of the change in the potential effects that federally listed species may experience from operation of the ocean intake system during operations versus during decommissioning.

Water Discharge Water returns to the Pacific Ocean via the Unit 2 discharge conduit, which extends into the ocean approximately 8,400 ft (2.6 km). The last 2,500 ft (0.8 km) (offshore end) of the discharge conduit consists of a diffuser containing 63 discharge nozzles, each 2 ft (0.6 m) in diameter, that are evenly spaced at 40-ft (12-m) intervals. The nozzles are oriented at a vertical angle of 20° above the horizontal and direct the discharge offshore alternatively at angles of 25° to the right and 25° to the left of the diffuser section centerline. (SCE 2016)

Water Withdrawal and Discharge Permitting Surface water withdrawals and discharges for both units are regulated by National Pollutant Discharge Elimination System (NPDES) permit no. CA0109282. The permit is implemented by an order administered by the San Diego Regional Water Quality Control Board (SDRWQCB): R9-2015-0073 (SDRWQCB 2015). SCE filed a permit renewal application in July 2020, 180 days prior to the expiration of the current permit in January 2021. SCE expects to receive a renewed permit in mid-2022.

Water Withdrawal and Discharge During Decommissioning Since SONGS ceased power operations in June 2013, SCE has greatly reduced ocean water withdrawal rates because water is no longer required for cooling. Remaining flow supports dilution of liquid effluent pathways. Currently, SONGS withdraws approximately 7,500 gpm (11.5 mgd) of water from the Pacific Ocean 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> per day, 7 days per week, at each of the two offshore intake structures (SCE 2021). This equates to a total of 16,000 gpm (23 mgd), or approximately 2 percent of the volume of water that the facility withdrew during power operations. 3 Velocity in the intake conduit associated with this change in flow has dropped from 7.42 fps (2.26 m/s) to 0.14 fps (0.04 m/s) under current conditions. Water is no longer chlorinated, and it is discharged back to the ocean at roughly the same temperature at which it was withdrawn. Water 3

During power operations, SONGS withdrew over 1,600,000 gpm (2,304 mgd) of water from the Pacific Ocean.

withdrawal and discharge would continue throughout the decommissioning period, which could be through 2035. However, as SCE refines the engineering and design of its decommissioning activities, the use of ocean water could cease earlier. (SCE 2021)

Large Organism Exclusionary Devices In 2016, SCE installed large organism exclusionary devices (LOEDs) at the primary offshore intake structures and at the auxiliary offshore intake structures. The LOEDs consist of a 9-in. by 9-in. (23-cm by 23-cm) Dyneema AS78 netting around the circumference of each intake. Dyneema AS78 has the highest abrasion resistance of any synthetic commercial grade fiber, and it is also inert to water and most chemicals, has very high breaking strength, and low elongation (i.e., it is stiff and doesnt stretch)

(NMFS 2016a). The State Water Resource Control Board (SWRCB) required SCE to install these devices under Section 2.C.(1) of its Water Quality Control Policy on the Use of Coastal and Estuarine Waters for Power Plant Cooling (OTC Policy) (SWRCB 2020). The OTC Policy establishes uniform, technology-based standards to implement Clean Water Act Section 316(b) and to reduce the harmful effects associated with cooling water intake structures on marine and estuarine life. Under this policy, LOEDs are required for all existing power plants with offshore intakes. The SDRWQCB incorporates the LOED requirements in Provision VI.C.6.a.ii. of the SONGS NPDES permit (SDRWQCB 2015). The NPDES permit also requires SCE to monitor the ocean water intake system to ensure that the LOEDs are functioning properly. Since SCE installed the LOEDs and reduced intake flow, no sea turtles have been entrained in the intakes. (SCE 2016, 2021)

Offshore Activities The intake and discharge conduits on the seabed are subject to the terms of the CSLC easement lease for the offshore land. The easement lease calls for removal of structures, building, pipelines, machinery, and facilities placed or erected by the lessee and restoration as nearly as possible to the conditions existing prior to their erection or placement (Enercon 2014). These removal and restoration activities would occur within a 21-ac (0.4-ha) area of tidal and submerged lands in the Pacific Ocean southwest of the SONGS facility. During decommissioning and subject to the lease agreement, SCE would remove the following:

• two primary offshore intake structures (one for each unit),

• two auxiliary intake structures (one for each unit),

• 12 diffuser structures (6 for each unit),

• 23 manhole access port structures (11 for Unit 2 and 12 for Unit 3),

• one fish return system, and

• three environmental monitoring buoys, two navigational buoys, and their associated water quality instruments and anchor blocks.

SCE would remove all structures to 4 ft (1.2 m) below the seabed except for the intake and discharge conduits, which would be abandoned in place. SCE would cut off the fish return conduit at its terminus and cap it with an exclusion barrier. Removal and any necessary restoration would occur over the course of the decommissioning period (through 2035). However, the dispositioning of conduits, which would involve the highest concentration of activity within the action area, would occur over a one-year period. As SCE refines the engineering and design of its decommissioning activities, offshore activities could be completed sooner than 2035. (SCE 2021) 4.0 Action Area The implementing regulations for ESA Section 7 define action area to mean all areas to be affected directly or indirectly by the Federal action and not merely the immediate area involved in the action (50 CFR 402.02). The action area effectively bounds the analysis of federally listed species and critical habitats because only species and habitats that occur within the action area may be affected by the Federal action.

The action area for the shutdown and decommissioning of SONGS under its existing NRC licenses includes the intake and discharge structures and the area immediately surrounding these structures. Because discharged water is no longer warmed or chlorinated, the proposed action results in no thermal or effluent plume.

The action area also includes a 21-ac (0.4-ha) area of tidal and submerged lands in the Pacific Ocean southwest of the facility. This is the area over which conduits would be dispositioned, where dredging may occur, and where barges or other watercraft may be used to transport materials. This area is authorized by CSLC Lease No. PRC 6785.1 and is referred to in this assessment as the CSLC lease facilities. Within this area are the two primary offshore intake structures (one for each unit), two auxiliary intake structures (one for each unit), 12 diffuser structures (6 for each unit), 23 manhole access port structures (11 for Unit 2 and 12 for Unit 3), one fish return system, and three environmental monitoring buoys, two navigational buoys, and their associated water quality instruments and anchors, all of which would be removed during decommissioning, as described previously. (SCE 2021)

Figure A1 in Appendix A is an aerial photograph of the SONGS site, and Figure A2 in Appendix A depicts the SONGS site layout with labels of the major buildings and structures and the exclusion area boundary.

The ocean floor in the vicinity of SONGS is an extensive shelf of soft sediments, consisting of both coarse and fine sands occasionally interrupted by areas of hard substrate. Ocean depths in the vicinity of SONGS vary from about 4 ft (1.2 m) along inshore areas to 118 ft (36 m) at 2 mi (3.2 km) offshore. Maximum water depth in the action area is approximately 50 ft (15 m). The ocean floor slopes evenly away from the shore, and ocean depth is about 30 ft at the SONGS offshore intakes. Just west of the intakes, the ocean floor drops off steeply, with depths exceeding 200 ft (60 m) in some areas. (Enercon 2014)

Ocean salinity is relatively constant in the action area. It ranges from 32 to 35 parts per thousand (ppt) with localized temporary variations attributable to runoff and precipitation (Enercon 2014).

Ocean temperatures in the action area range from approximately 57 °F (14 °C) in January to 68 °F (20 °C) in August. The increase in ocean temperatures from January to August is relatively slow, whereas temperatures drop more rapidly from autumn to early winter. SCE records temperatures at monitoring stations in compliance with the SONGS NPDES permit and produces an annual report.

Pacific Ocean currents north of the equator generally flow in a clockwise direction so that most waters flow north-to-south down the California coast (Barnes and Hughes 1988).

However, because of the shape of the shoreline from Point Conception (approximately 150 mi (240 km) north of SONGS) southward, circulation adjacent to the SONGS site is directed by the Southern California Counter Current (CSU-LB 2021), which creates a dominant southeast-to-northwest current. However, more shoreward currents in the vicinity tend to flow in a south and southeast direction (Enercon 2014). Ocean current velocities offshore of SONGS typically range from 0.1 to 0.7 fps (0.03 to 0.2 m/s) in most seasons (Enercon 2014). Localized eddies and upwelling may be caused by local geomorphology and tidal effects, though the ocean floor surrounding the intake and discharge structures is flat and not affected by currents (Enercon 2014).

The below descriptions of the plankton, macroinvertebrate, fish, marine mammal, and aquatic plant communities are summarized from Enercons SONGS Units 2 and 3 Environmental Impact Evaluation, Decommissioning Supplemental Environmental Analysis (Enercon 2014) unless otherwise cited.

Aquatic Plants The richest area of marine flora near the action area is the shallow subtidal zone approximately 1,300 ft (400 m) up the coast from SONGS. This area supports a biological community dominated by surfgrass (Phyllospadix spp.) and feather boa kelp (Egregia menziesii), which grows as an annual or perennial depending upon the depth of the holdfast. Giant kelp can form dense beds that provide an intricate three-dimensional habitat that attracts numerous invertebrates and fish. The presence of kelp forests can have significant influence on the structure and density of the local fish community (Holbrook et al. 1990).

The closest stand of giant kelp is the San Onofre kelp bed, which lies 656 ft (200 m) down the coast from the SONGS Unit 2 diffusers at a depth of about 40 to 50 ft (12 to 15 m). In 1990, canopy measurements of the San Onofre kelp bed varied from zero to 189 ac (76.3 ha); however, since 1966, canopy measurements have averaged much smaller at 67.8 ac (27.4 ha) annually for the period 2003-2016 (MBC 2017). Because kelp can be annual or perennial, kelp bed canopy cover is highly variable. For instance, in 2013, the San Onofre kelp bed was 190 ac (76.7 ha), which represented a four-fold increase from the previous year (MBC 2017). In 2015, the bed decreased in size by 93 percent to 10.6 ac (4.3 ha), and in 2016, it tripled in size and covered an area of 30 ac (12.0 ha) (MBC 2017). This area contains cobble and boulder substrates, which are the preferred habitat for the attachment of giant kelp.

Plankton Plankton are small and often microscopic organisms that drift or float in the water column. Phytoplankton are single-celled plant plankton and include diatoms (single-celled yellow algae) and dinoflagellates (a single-celled organism with two flagella).

Phytoplankton live suspended in the water column and occur in the limnetic (open water) zone. Zooplankton are animals that either spend their entire lives as plankton (holoplankton) or exist as plankton for a short time during development (meroplankton). Zooplankton include rotifers, isopods, protozoans, marine gastropods, polychaetes, small crustaceans, and the eggs and larval stages of insects and other aquatic animals.

As part of Clean Water Act Section 316(b) requirements, SCE undertook plankton studies at SONGS to determine the composition and abundance of ichthyoplankton and shellfish larvae entrained by SONGS. Researchers collected samples from inside the plant and at various depths near the offshore intakes every two weeks from March 2006 through April 2007. The most abundant larval fish taxa collected in all offshore samples were northern anchovy (Engraulis mordax); California grunion (Leuresthes tenuis);

unidentified silversides (Atherinopsidae); and jacksmelt (Atherinopsis californiensis).

Shoreline surface samples were dominated by grunion, silversides, jacksmelt, and kelpfishes (Clinidae).

Over 15 fish species appeared in offshore surface samples. Grunion, jacksmelt, silversides, and northern anchovy were the dominant species. Total larval fish densities (measured as the number of individuals collected per 1,000 m3) were a half to a third of total inshore surface densities. Fish larvae in the offshore water column were dominated by white croaker (Genyonemus lineatus) and anchovies (Engraulidae). Northern anchovy, unidentified gobies (Gobiidae), white croaker, and bay goby (Lepidogobius lepidus) were the most abundant larval taxa in the suprabenthos zone. Densities of total larvae collected from the offshore suprabenthos were about twice as high as larval densities at the surface and about eight times higher than water column densities.

These findings paralleled those found in an earlier study performed from 1974 through 1976 in the Southern California Bight (Gruber et al. 1982), which found that anchovies accounted for 83 percent of all larvae collected. Lavenberg et al. (1986) also found that the northern anchovy dominated ichthyoplankton samples taken in nearshore areas of southern California. More recent findings by Suntsov et al. (2012) support the profile of larvae species and density found during SCEs 2006-2007 study. Suntsov et al. (2012) found the Southern California Bight to be structured by larval jack silverside, northern anchovy, croakers, combtooth blennies, pipefishes, silversides, clinids, labrisomids, and clingfishes (Gobiesox spp.).

SCE selected five species of invertebrate larvae for monitoring during the demonstration study: the brown rock crab (Cancer antennarius); yellow crab (C. anthonyi); red rock crab (C. productus); slender crab (C. gracilis); and the California spiny lobster (Panulirus interruptus). The most abundant selected invertebrate larvae collected offshore during the same studies were slender crab megalops, yellow crab megalops, and brown rock crab megalops. Densities were very low compared with fish eggs and larvae, and there was no clear distributional pattern.

Macroinvertebrates Intertidal habitat in the vicinity of SONGS is comprised primarily of sand and cobble with occasional rocky areas. Subtidal areas are characterized by softer sand sediments composed of both coarse and fine particles with occasional areas of hard substrate.

This intertidal habitat supports a diversity of marine worms, crustaceans, and some bivalves and gastropods. Macroinvertebrate groups identified in the offshore benthos between 1963 and 1975 primarily included mollusks and polychaete worms, with some crustaceans, ectoprocts, cnidarians, and echinoderms.

The California Department of Fish and Wildlife (CDFW) identifies the following commercially important and sport harvest invertebrate species in southern California (CDFW 2013):

• Rock crabs whose commercial harvest is most active in southern California.

• Sheep crabs (Loxorhynchus grandis), also known as spider crabs.

• Seven species of abalone that feed on giant kelp (Macrocystis pyrifera) and bull kelp (Nereocystis luetkeana) and that are preyed upon by rays and sea otters. 4 Most California abalones are found in boulder and rock habitat associated with kelp forests. Abalone abundance is highest where physical conditions allow good kelp growth and where drift kelp is available.

• Red sea urchin (Strongylocentrotus franciscanus) is commercially harvested and preyed upon by sea otters.

• Purple sea urchin (Strongylocentrotus purpuratus) is not as commercially popular as the red urchin. It is a voracious kelp pest and is also preyed upon by sea otters.

• Spiny lobster, which occurs in shallow, rocky coastal areas from Point Conception to the U.S.-Mexico border and off southern California islands. During their first two years, juveniles inhabit surfgrass beds from the lower intertidal to depths of about 16 ft (4.8 m). Juveniles and adults are considered benthic and occur from the intertidal zone to about 262 ft (80 m).

Fish The offshore habitat in the action area consists of a mixture of sand, cobble, and isolated areas of exposed rock, which are generally less biologically productive than solid substrate outcropping but more productive than sandy bottoms. Bottom substrates shift from stable cobble and boulders at the San Mateo Point area, northwest of SONGS, to mostly sand with isolated patches of cobble and rock at Don Light, southeast of SONGS.

The area of richest marine productivity in the immediate vicinity of the plant site is the shallow subtidal zone that lies approximately 1,300 ft (396 m) up the coast from SONGS.

This area contains beds of surfgrass and feather boa kelp (Egregia menziesii).

The local benthic fish community is generally dominated by queenfish (Seriphus politus),

northern anchovy, white croaker, and speckled sanddab (Citharichthys stigmaeus).

These species account for 77 percent of the long-term trawl sampling conducted in association with NPDES permitting requirements since 1979.

The San Onofre kelp bed, down the coast from SONGS, supports a diverse assemblage of fish. Prevalent species include senorita (Oxyjulis californica), salema (Xenistius californica), halfmoon (Medialuna californiensis), kelp bass (Paralabrax clathratus), jack mackerel (Trachurus symmetricus), Pacific barracuda (Sphyraena argentea), and kelp perch (Brachyistius frenatus). The benthic kelp forest community is dominated by senorita, rock wrasse (Halichoeres semicinctus), kelp bass, black perch (Embiotoca 4

NatureServe Explorer (2021) reports no populations of southern sea otters (Enhydra lutris nereis) closer than Ventura County.

jacksoni), barred sand bass (Paralabrax nebulifer), pile perch (Rhacochilus vacca), white seaperch (Phanerodon furcatus), and California sheephead (Semicossyphus pulcher).

Although rocky intertidal and subtidal habitats are not present in the immediate vicinity of SONGS, areas of low-relief cobble substrate are present in the vicinities of both the San Onofre and San Mateo kelp beds. Reef-associated fish communities of this region include kelp bass, garibaldi (Hypsypops rubicundus), barred sand bass, giant sea bass (Stereolepis gigas), kelp blennies (Gibbonsia spp.), and sargo (Anisotremus davidsonii).

During a 2012 demersal fish trawl survey associated with SONGS, researchers collected 5,856 fish representing 41 species with an overall species diversity of 2.08. Summer sampling resulted in the highest abundance (2,131 fish), while the spring survey recorded the most species (29 species). Species diversity was highest in the fall (1.81).

White croaker, northern anchovy, and queenfish were the most abundant species.

Catches at the control stations of San Mateo and Don Light alternated as the most and least abundant, while survey stations offshore of SONGS were in the middle except in winter. In association with this effort, SCE researchers reviewed 17 years of quarterly trawl survey data and determined that there is a high level of similarity among the deepest survey stations, while stations along the two shallowest isobaths exhibited more variation.

The region near SONGS is an important barred sand bass fishing area. This species became very popular by the mid-1950s and has consistently ranked among the top ten in the southern California marine sportfish catch since the late 1970s.

Kelp bass are one of the most important nearshore recreational species of southern California. This species has been targeted by southern California anglers since the early 1900s. The most productive fishing areas for kelp bass in recent years have been off the Coronado Islands in Baja California, Mexico; Point Loma and La Jolla in San Diego County; Dana Point and Huntington Beach in Orange County; Horseshoe Kelp in Los Angeles County; and around the Channel Islands.

Ocean whitefish (Caulolatilus princeps) are found in loosely aggregated schools near high-relief seafloor structures such as shallow banks, rocky reefs, and kelp beds. Ocean whitefish are diurnally active and range from sand areas during the day and areas of high relief at night. They prefer offshore islands to the mainland coast and are abundant at Santa Rosa, Santa Barbara, Santa Catalina, and San Clemente Islands. They are frequently found in association with members of the rockfish family (Scorpaenidae) and California sheephead. The ocean whitefish supports both a recreational and commercial fishery.

Eighteen species of surfperches (family Embiotocidae) are identified in California coastal waters. According to the CDFW (2013), there is a significant recreational fishery for many of these species in southern California. Over half of the barred (Amphistichus argenteus), black (Embiotoca jacksoni), sharpnose (Phanerodon atripes) and walleye surfperch (Hyperprosopon argenteum), and significant percentages of the total calico (Amphistichus koelzi), pile (Rhacochilus vacca), rubberlip (Rhacochilus toxotes), silver surfperch (Hyperprosopon ellipticum), and white seaperch (Phanerodon furcataus) caught in California are caught south of Point Conception.

California halibut (Paralichthys californicus) is an important flatfish species in both the commercial and recreational fisheries of central and southern California, though landings have dropped substantially over the last 40 years. Historically, the fishery has been centered off southern California and Baja California, Mexico, but over the past 30 years, the greatest landings have oscillated between ports in southern and central California.

Most of the halibut landings in central California occurred in the San Francisco area. A limited amount of fishing occurs around the Channel Islands of southern California, which yield substantially larger halibut than those caught in the nearshore mainland fishery.

Marine Reptiles Four species of federally listed sea turtles occur off the coast of southern California:

loggerhead sea turtle; green sea turtle; leatherback sea turtle; and olive ridley sea turtle.

Sea turtles are highly migratory and use a wide range of broadly separated localities and habitats during their lifetimes. Sea turtles are described in detail in Section 5.0 of this assessment.

Marine Mammals Several marine mammals inhabit or are known to visit coastal waters of southern California. Six whales and two pinnipeds are federally listed as threatened or endangered for California. Blue, sperm, fin, humpback, sei, and gray whales transit the region from their calving grounds to the south and feeding grounds farther north. Two federally listed pinnipeds that occur in southern California are the Guadalupe fur seal (Arctocephalus townsendii) and stellar sea lion (Eumetopias jubatus).

Four other pinniped species occur in southern California: California sea lions (Zalophus californianus), northern fur seals (Callorhinus ursinus), northern elephant seals (Mirounga angustirostris), and Pacific harbor seals (Phoca vitulina richardsi). While all prefer offshore islands for birthing and rookeries, some have mainland haul-outs. San Miguel Island, off Santa Barbara, appears to be the southernmost extent of the northern fur seal range. The Guadalupe fur seal is only seen occasionally at islands in the Southern California Bight and the Farallon Islands by San Francisco. Of the six pinniped species that inhabit southern California, only California sea lions and harbor seals have been recorded as occurring in the vicinity of the SONGS site.

5.0 Federally Listed Species The NRC staff evaluated the potential for federally listed marine species to occur in the action area based on a combination of habitat preferences, life history characteristics, survey data, incidental take reports, scientific literature, and other relevant information.

Table A1 summarizes the results of the staffs evaluation. Based on its review, the staff determined that the following species are unlikely to occur in the action area:

• green sturgeon, Southern distinct population segment (DPS),

• California steelhead, South Central California DPS and Southern California DPS,

• sei whale,

• sperm whale,

• black abalone, and

• white abalone.

The NRC staff determined that these species are unlikely to occur in the action area because there are either no records of the species in the action area, the action area lacks suitable habitat, or both. With respect to abalone, surveys performed to support permitting in support of SCEs installation of the LOEDs on the offshore intake structures did not detect any abalone species. In a 2016 ESA Section 7 consultation with the USACE concerning this project, NMFS (2016a) agreed with the USACEs determination that there was no evidence that abalone were present in the area. The above species are excluded from further analysis in this biological assessment, and the NRC staff concludes that the proposed action would have no effect on these species.

The NRC staff determined that the following species have a low likelihood of occurring in the action area because there are no specific records of the species in the action area and habitat is marginal. Nonetheless, the following species may rarely to occasionally transit the action area, especially during seasonal migrations:

• Guadalupe fur seal,

• blue whale,

• fin whale,

• humpback whale, Central American and Mexico DPSs, and

• gray whale, Western North Pacific DPS.

The NRC staff determined that the following species have a moderate likelihood of occurring in the action area because these species were documented in the vicinity of the action area in past or historic surveys or scientific literature or because suitable habitat is found in action area within the species known geographic range:

• loggerhead sea turtle, North Pacific Ocean DPS,

• green sea turtle, East Pacific DPS,

• leatherback sea turtle, and

• olive ridley sea turtle.

The remainder of this section describes the life history, identification, range, habitat associations, and diet of the marine mammal and sea turtle species listed above as potentially occurring in the action area. Section 7.0 of this assessment analyzes the potential impacts of the proposed action on these species.

5.1 Guadalupe Fur Seal The U.S. Fish and Wildlife Service (FWS) initially listed the Guadalupe fur seal under the Endangered Species Preservation Act of 1966 (ESPA), the predecessor to the ESA (35 FR 8491). In 1985, NMFS designated the species as threatened under the ESA (50 FR 51252). NMFS has not developed a recovery plan for this species, but the FWS issued a status review report for the species in 2021 (McCue et al. 2021).

5.1.1 Description and Life History Identification Guadalupe fur seals are dark brown to silver with thick tan-colored underfur. Individuals are sexually dimorphic. Males are considerably longer and larger and can grow up to three to four times the weight of adult females. Adult males are greater than 8 ft (2.5 m) in length and weigh over 485 lbs (220 kg); adult females average 5 ft (1.5 m) in length and 110 lbs (50 kg) in weight. The species has long whiskers, and those of adult females are typically white. Guadalupe fur seals have long, prominent, slightly downturned ear pinnae, and the snout is elongated and pointy with a flattened top. Adult males have a mane comprised of longer and thicker guard hairs that may appear slightly reddish in hue. (McCue et al. 2021)

Life History Guadalupe fur seals breed from May through August. During this period, males establish and defend territories to gain access to females. Males mate with numerous females during a single breeding season. Pups are born from July through August, and females nurse their young until approximately 9 months of age. Adult females tend to remain around the breeding areas while nursing, while males appear to migrate away from these areas during winter. Age at sexual maturity is unknown, although females of other Arctocephalus species, such as the southern fur seal (Arctocephalus gazelle),

reach sexual maturity around 3 to 5 years of age, and males do not establish territories until they are approximately 7 to 10 years old. (McCue et al. 2021)

Guadalupe fur seals do not migrate, although they may travel great distances from breeding grounds. When at sea, Guadalupe fur seals are solitary and non-social. They tend to hunt and feed alone. (NMFS 2021a)

Range Most of the Guadalupe fur seal population is centered on Guadalupe Island, a volcanic oceanic island off the west coast of the Baja California Peninsula, Mexico where nearly all (over 99 percent) pups are born. In recent years, a small number of pups (less than 30 per year) have also been born at the San Benito Archipelago. Guadalupe fur seals can be found in waters along the west coast of North America from central Mexico to southern British Columbia, Canada. The species is occasionally, but rarely sighted in Alaska. In the U.S., Guadalupe fur seals haul out on the California Channel Islands and occasionally on the Farallon Islands. (McCue et al. 2021)

Habitat Preferred habitat of the Guadalupe fur seal is characterized by basaltic rocks and boulders bounded by high cliffs that contain a variety of sizes of crevices along narrow coastlines. (McCue et al. 2021)

Diet Guadalupe fur seals mainly feed on squid and other cephalopods, although they also eat fish, including myctophids, mackerel, anchovies, and sardines. The species feeds within the California Current System, which spans from the coast to 560 mi (900 km) offshore and extends from the southern tip of Vancouver Island, British Columbia to the tip of the Baja California Peninsula, Mexico. When hunting, Guadalupe fur seals stay at depths shallower than 670 ft (200 m) and feed mostly between dusk and dawn when prey are closer to the surface. (McCue et al. 2021) 5.1.2 Occurrence Within the Action Area Although there are no known occurrences of the Guadalupe fur seal in the action area, the species is known to haul out on the Channel Islands, which lie approximately 100 mi (160 km) west of SONGS. Therefore, Guadalupe fur seals could occasionally transit the action area to hunt or forage. The action area does not provide suitable land habitat, so the species would only be expected to occur within the water column.

5.2 Whales 5.2.1 Life History The life history of all whale species is similar. Individuals become sexually mature at between 6 and 13 years, depending on the species. Females usually mature earlier than males. Mating typically occurs during distinct seasons and in specific ocean regions. Most baleen whales mate and birth in warm tropical waters in the winter.

Orcas and other toothed whales may mate throughout the year. Different species show various courtship behaviors, and both females and males will mate with several different individuals to increase their chances of reproduction.

Females migrate to calving grounds to give birth to live young after a gestation period of between 10 and 18 months, depending on the species. Females produce one calf every three to five years, and calves nurse for up to three years. Most females travel from the Arctic or Antarctic into the tropics to mate, calve, and raise young during the winter and spring. Mothers then migrate with their young back to the poles in the warmer summer months.

During the adolescent period, females generally stick close to their mother and other females that assisted in their raising. Males begin associating with other males of a similar age to form juvenile and bachelor pods. Towards the end of adolescence, males will leave their mothers pods completely.

Whales are social, and the majority live in small-to-medium-sized pods for at least some part of the year. Whales will often congregate for specific activities, including breeding, traveling, feeding, and rearing young.

All whales are carnivorous and predatory, and many species are generalist, opportunistic feeders. Toothed whales mostly feed on fish and cephalopods, followed by crustaceans and bivalves. Baleen whales mostly feed on krill and plankton, followed by crustaceans and other invertebrates. A few species are specialists. Examples include the blue whale, which eats almost exclusively krill, the sperm whale, which specializes on squid, and the gray whale which feeds on bottom-dwelling invertebrates.

Most whales have no natural predators. Orcas will occasionally work together in a group to attack juvenile or weakened baleen whales. Sharks, walruses, and polar bears occasionally consume smaller toothed whales.

5.2.2 Blue Whale The FWS initially listed the blue whale under the ESPA (35 FR 8491). The species was then designated as endangered under the ESA, once promulgated. NMFS issued a revised recovery plan, Recovery Plan for the Blue Whale: First Revision to the July 1998 Recovery Plan for the Blue Whale, in 2020 (NMFS 2020a).

Identification Blue whales are the largest animal on earth. They have a long body and slender shape with mottled blue-gray coloring that appears light blue underwater. In the North Atlantic and North Pacific, the species can grow up to 90 ft (27 m) and weigh over 100,000 lbs (45,000 kg). In the Antarctic, the species can grow up to 110 ft (34 m) and weigh more than 330,000 lbs (150,000 kg). Females are generally larger than males. (NMFS 2021b)

Range Blue whales inhabit all oceans except the Arctic. Along the west coast of the U.S., blue whales spend winters off Mexico and Central America and likely feed in summer off the coast and, to a lesser extent, in the Gulf of Alaska and central North Pacific waters.

(NMFS 2021b)

Habitat In the summer, blue whales inhabit polar waters. In winter, individuals migrate to equatorial waters to breed, although some evidence suggests that in certain areas, blue whales do not migrate at all. Off the west coast of the U.S., the species is often observed in shelf waters. The Gulf of California appears to be an important calving area from December through March. (NMFS 2021b)

The U.S. West Coast is an important feeding area in summer and fall but, increasingly, blue whales from the Eastern North Pacific DPS are found feeding north and south of this area in summer and fall. Nine biologically important areas for blue whale feeding are identified off the California coast, including six areas in southern California and three in central California. (NMFS 2020c)

Diet Blue whales feed almost exclusively on krill, although fish and copepods may occasionally be part of the species diet. Individuals can eat up to 13,000 lbs (6,000 kg) of krill per day. (NMFS 2021b) 5.2.3 Fin Whale The FWS initially listed the fin whale under the ESPA (35 FR 8491). The species was then designated as endangered under the ESA, once promulgated. NMFS issued a revised recovery plan, Final Recovery Plan for the Finback Whale, in 2010 (NMFS 2010).

Identification The fin whale is the second largest whale species. It is named for the tall, hooked dorsal fin near the tail. Fin whales have a sleek, streamlined body with V-shaped heads. They are black or dark brownish gray on the back and sides and white on the underside.

Head coloring is asymmetrical: dark on the left side of the lower jaw, white on the right side of the lower jaw, and the reverse on the tongue. Individuals can grow up to 85 ft (26 m) long and weigh up to 160,000 lbs (72,000 kg). (NMFS 2021c)

Range Fin whales occupy the temperate and polar latitudes of all major oceans. The species is less common in the tropics. Most individuals migrate from Arctic and Antarctic feeding areas in the summer towards the equator to temperate breeding and calving areas in the winter. Winter breeding ground locations are not known. (NMFS 2021c)

Habitat Fin whales occupy deep, offshore waters. They occur year-round in a wide range of locations, but the density of individuals in any one area changes seasonally. When migrating, fin whales travel in the open seas away from the coast. (NMFS 2021c)

Fin whales satellite-tagged in the Southern California Bight use the region year-round, although they seasonally range to central California and Baja California before returning to the Southern California Bight (NMFS 2020d). The longest satellite track reported by Falcone and Schorr (2013) was a fin whale tagged in the Southern California Bight in January 2014. The whale moved south to central Baja California by February and north to the Monterey area by late June.

Diet Fin whales feed on krill, small schooling fish, and squid by lunging into schools of prey with their mouth open and then filtering the food from the water. Fin whales are often seen feeding in large groups that include humpback whales, minke whales (Balaenoptera acutorostrata), and Atlantic white-sided dolphins (Lagenorhynchus acutus). (NMFS 2021c) 5.2.4 Humpback Whale The FWS initially listed the humpback whale under the ESPA (35 FR 8491). The species was then designated as endangered under the ESA, once promulgated. In 2016, NMFS designated 14 DPSs of humpback whale (81 FR 62259; 81 FR 93639). Of the two DPSs that may occur in the action area, the Central American DPS is threatened, and the Mexico DPS is endangered. NMFS issued a revised recovery plan, Final Recovery Plan for the Humpback Whale, in 1991 (NMFS 1991).

Identification Humpback whales are primarily black with different amounts of white on their pectoral fins, bellies, and tails. Tails are serrated along the trailing edge, pointed at the tips, and up to 18 ft (5.5 m) wide. Adults can grow up to 60 ft (18.3 m) long and weigh up to 80,000 lbs (36,300 kg). (NMFS 2021d)

Range Humpback whales inhabit all major oceans. They travel great distances during migration with some animals migrating 5,000 mi (8,000 km) between high-latitude summer feeding grounds and winter mating and calving areas in tropical waters. Both the Central American and Mexico DPSs feed in Antarctic or sub-Antarctic waters. (NMFS 2021d)

Habitat While calving, humpbacks prefer shallow, warm waters near offshore reef systems or shores. They generally feed in cold, productive waters. Humpback whales can be found close to shore and often display activity near the surface, such as breaking or slapping the surface with their pectoral fins and tails. (NMFS 2021d)

Along the U.S. West Coast, humpback whales feed off the coast in the summer. NMFS (2020d) believes that most of these whales originate from the Mexico DPS with small numbers originating from the Central American DPS. Whales from both DPSs may belong to the California and Oregon feeding group within a single stock (NMFS 2020e).

Diet Humpback whales filter feed on krill and small fish. Whales may hunt in groups and corral schools of fish by creating curtains of air bubbles and pushing the schools to the surface. (NMFS 2021d) 5.2.5 Gray Whale The FWS initially listed the gray whale under the ESPA (35 FR 8491). The species was then designated as endangered under the ESA, once promulgated, as two stocks:

Western North Pacific DPS and Eastern Pacific DPS. In 1994, NMFS delisted the Eastern North Pacific DPS (59 FR 31094). The Western North Pacific DPS remains endangered. NMFS has not issued a recovery plan for the gray whale.

Identification Gray whales are mottled gray with small eyes located just above the corners of the mouth. The pectoral flippers are broad, paddle shaped, and pointed at the tips. Gray whales have a dorsal hump instead of a dorsal fin and a series of small bumps, called knuckles, between the dorsal hump and tail. Adults can grow up to 49 ft (15 m) long and weigh up to 90,000 lbs (40,800 kg). (NMFS 2021e)

Range Gray whales are only found in the North Pacific Ocean. One population inhabits the eastern region of this ocean, and one population inhabits the western region. The species makes one of the longest annual migrations of any mammal. Individuals travel about 10,000 mi (16,100 km) roundtrip (NMFS 2021e). Some gray whales that feed off Sakhalin Island, Russia in summer migrate east across the Pacific to the west coast of North America in winter, while others migrate south to waters off Japan and China (NMFS 2020c).

Habitat Gray whales primarily occupy shallow coastal waters. During migration, individuals may cross deep waters far from shore. In January and February, females calve in shallow lagoons and bays of Mexico (NMFS 2021e).

Diet Gray whales are bottom feeders that consume a wide range of benthic and epibenthic invertebrates, such as amphipods. Individuals suck sediment and food from the sea floor by rolling on their sides and swimming along slowly to filter food through their baleen plates. (NMFS 2021e) 5.2.6 Occurrence Within the Action Area In a 2016 ESA Section 7 consultation with the USACE concerning installation of the LOEDs at SONGS, NMFS (2016a) found that humpback whales are occasionally observed in the Southern California Bight. Blue and fin whales may also occur near the action area with blue whales especially more likely to be found foraging along the southern California coast for extended periods of time during the summer and fall months. However, NMFS (2016a) considered the presence of any of these whales within 0.6 mi (1 km) of shore and in waters less than 33 ft (10 m) deep unlikely based on historic survey data and habitat prediction models developed by the Southwest Fisheries Science Center (Barlow and Forney 2007; Becker et al. 2012). This relatively shallow nearshore area, which corresponds to the location of the SONGS offshore intake structures, is not known or expected to be an area for whale foraging or any other important behaviors. The most recent NMFS (2019) stock assessment of the gray whale indicates that this species migrates near the action area each year and that some migrating individuals are likely part of the Western North Pacific DPS.

5.3 Sea Turtles 5.3.1 Life History The life history of all sea turtle species is similar. Mature, breeding females migrate from foraging grounds to nesting beaches, which may be nearby or a significant distance away. Turtles mate some time during the migration, usually in the spring, when mature males and females congregate off nesting beaches. Females return to land to nest.

Gravid females usually crawl up on a dark beach to above the high-tide point at night.

Females generally deposit from 1 to 10 egg clutches per season at intervals of 10 to 20 days, and a female will only nest every two to four years. Once females deposit their eggs, they return to the ocean. Olive ridleys exhibit slightly different nesting behavior.

Females congregate during the day and nest in groups called arribada, and females of this species tend to nest every year.

Eggs incubate for about two months. Hatchlings emerge from the nest on a single night, travel over the beach and enter the ocean as a group, and swim to offshore waters within the first 24 to 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />. There they spend the next several years feeding in sargassum beds, upwellings, and convergence zones of the open ocean.

Juveniles of most species move into bays and estuaries of the coastal zone, where they spend more years feeding and growing to maturity. Each species reaches sexual maturity at different ages, and maturity also varies among populations within the same species. For instance, loggerheads reach maturity in 12 to 30 years, and green turtles reach maturity in 20 to 50 years. Once mature, sea turtles join the adult populations in nesting and foraging grounds.

5.3.2 Loggerhead Sea Turtle The loggerhead sea turtle is the most common nesting sea turtle found in U.S. coastal waters. NMFS initially listed the species as federally threatened in 1978 (43 FR 32800).

In 2011, NMFS issued a final rule that designates nine DPSs of the species (76 FR 58868). The DPS that occurs in the action area, the North Pacific Ocean DPS, remains federally endangered. NMFS and the FWS jointly issued Revision 1 to the species recovery plan, Recovery Plan for U.S. Pacific Populations of the Loggerhead Turtle, in 1998 (NMFS and FWS 1998a).

Identification Adult, subadult, and juvenile loggerheads have reddish-brown carapaces and dull brown to yellowish plastrons. Loggerheads have more than one pair of prefrontal scales between the eyes and five lateral scutes on the carapace. Hatchlings and juveniles have sharp keels on the vertebral scutes, which recede with age. Hatchlings are mostly dark brown, their flippers have white to white-gray margins, and the bottom shell is generally yellowish to tan. (NMFS 2021f)

Range Loggerheads are found worldwide primarily in subtropical and temperate regions of the Atlantic, Pacific, and Indian Oceans, and in the Mediterranean Sea. Along the Atlantic coast, the species range extends from Newfoundland to Argentina. Along the Pacific coast, loggerheads range from the Gulf of Alaska southward but are most frequently seen off the western Baja Peninsula. Nesting occurs in the northern and southern temperate zones and subtropics. The North Pacific Ocean DPS only nests on the coasts of Japan. (NMFS 2021f)

Habitat Loggerheads are a nearshore species. Juveniles and adults may be found in a variety of habitats from turbid, muddy-bottomed bays and bayous to sandy bottom habitats, reefs, and shoals. Hatchlings and juveniles are associated with sargassum and pelagic drift lines of convergence zones. (NMFS 2021f)

Diet Loggerheads are carnivores and only occasionally consume plant material. During their open ocean phase, they feed on a wide variety of floating items. Juveniles and adults in coastal waters eat mostly bottom-dwelling invertebrates such as whelks, other mollusks, and crabs, especially horseshoe crabs. (NMFS 2021f) 5.3.3 Green Sea Turtle The green turtle is the largest hard-shelled marine turtle and the second most common nesting turtle in U.S. waters. NMFS initially listed the species as federally threatened in 1978 (43 FR 32800). In 2016, NMFS issued a final rule that designates 11 DPSs of the species (81 FR 20058). The DPS that occurs in the action area, the East Pacific Ocean DPS, remains federally threatened. NMFS and the FWS jointly issued a recovery plan, Recovery Plan for U.S. Pacific Population of the East Pacific Green Turtle, in 1998 (NMFS and FWS 1998b).

Identification Adult green turtles are 3 to 4 ft (0.9 to 1.2 m) long and weigh 300 to 350 lbs (136 to 159 kg). This species has a dark brown, gray, or olive colored shell and a much lighter, yellow-to-white underside. Shells have five scutes running down the middle and four scutes on each side. Other distinct characteristics of the green turtle are their serrated beak on the lower jaws and two large scales located between the eyes. (NMFS 2021g)

Range Green turtles are found worldwide primarily in subtropical and temperate regions of the Atlantic, Pacific, and Indian Oceans, and in the Mediterranean Sea. In U.S. waters, green turtles are found in inshore and nearshore waters from Texas to Maine, the U.S. Virgin Islands, and Puerto Rico. In the eastern North Pacific, green turtles have been sighted as far north as southern Alaska, but most commonly occur from southern California to northwestern Mexico. Elsewhere in the U.S. Pacific, green turtles occur in Hawaii, American Samoa, Guam, and the Commonwealth of the Northern Mariana Islands. Major nesting areas are in Costa Rica, Australia, Ascension Island, and Surinam. Smaller numbers nest in Florida, the U.S. Virgin Islands, and Hawaii. Culebra Island, Puerto Rico, is an important foraging area for juveniles. (NMFS 2021g)

Habitat Hatchlings and juveniles inhabit open ocean convergence zones, and subadults and adults inhabit nearshore benthic foraging areas consisting primarily of seagrass and algae beds. Subadults and adults can also be found over coral and worm reefs and rocky bottoms. In the U.S., important foraging areas include Florida estuaries, such as the Indian River Lagoon, and the French Frigate Shoals in Hawaii. (NMFS 2021g)

Diet Green turtles are the only herbivorous marine turtle. The diet of adults mainly consists of algae and seagrasses, although they may also forage on sponges, invertebrates, and discarded fish, especially in the juvenile stage. (NMFS 2021g) 5.3.4 Leatherback Sea Turtle The leatherback sea turtle is the largest marine turtle species and the only species that lacks scales and a hard shell. The species is federally listed as endangered throughout its range. The FWS initially listed the leatherback under the ESPA (35 FR 8491). The species was then designated as endangered under the ESA, once promulgated. In 2020, NMFS considered whether to list DPSs of the species, but NMFS ultimately determined that this action was not warranted (85 FR 48332). NMFS and the FWS jointly issued a recovery plan, Recovery Plan for U.S. Pacific Population of the Leatherback Turtle, in 1998 (NMFS and FWS 1998c).

Identification The leatherback has a primarily black, rubbery skin with pinkish-white coloring on its underside. The species lacks scales; rather, the carapace consists of small, interlocking dermal bones beneath the skin that overlie a supportive layer of connective tissue and fat and the deeper skeleton. The carapace has seven ridges along its length and tapers to a blunt point. The front flippers are proportionally longer than in other sea turtles and the back flippers are paddle shaped. Both their rigid carapace and their large flippers make the leatherback uniquely equipped for long distance foraging migrations. (NMFS 2021h)

Range Leatherbacks occur in the Atlantic, Pacific, and Indian Oceans. Nesting beaches are primarily located in tropical latitudes around the world. The largest remaining nesting aggregations occur in Trinidad and Tobago, West-Indies (Northwest Atlantic) and Gabon, Africa (Southeast Atlantic). Leatherbacks occupy U.S. waters in the Northwest Atlantic, West Pacific, and East Pacific. Within the U.S., most nesting occurs in Puerto Rico, and the U.S. Virgin Islands, and a small number of females also nest each year in Florida. (NMFS 2021h)

Habitat Leatherbacks are primarily pelagic, deep-diving animals. They are occasionally seen in coastal waters, typically within the nesting season. (NMFS 2021h)

Diet Leatherbacks lack the crushing, chewing plates characteristic of other sea turtles that feed on hard-bodied prey. Instead, they have pointed tooth-like cusps and sharp-edged jaws adapted for a diet of soft-bodied open ocean prey, such as jellyfish and salps.

They may also feed on colonial tunicates (pyrosomas) found in the pelagic zone.

(NMFS 2021h) 5.3.5 Olive Ridley Sea Turtle The olive ridley is the smallest marine turtle species. It is likely the most numerous marine turtle globally, but it is rare in U.S. waters. NMFS initially listed the species under the ESA in 1978 (43 FR 32800). Mexicos Pacific coast breeding populations are federally endangered, and all other populations are federally threatened. NMFS and the FWS jointly issued Revision 1 to the species recovery plan, Recovery Plan for U.S.

Pacific Populations of the Olive Ridley Turtle, in 1998 (NMFS and FWS 1998d).

Identification Adult olive ridleys have a nearly round dark gray carapace. Hatchlings are gray-brown.

Olive ridleys have two claws on each limb, more than one pair of prefrontal scales, and six or more lateral scutes.

Range Olive ridleys are found in Pacific and South Atlantic waters and may occasionally be found in the tropical North Atlantic. Along the Pacific coast, the species ranges from the Gulf of Alaska to Central America and is most common in the southern portion of this range. Large arribadas occur at two sites on Costa Ricas Pacific coast, one arribada occurs on Mexicos Pacific coast, and two or three occur in northeastern India. Smaller nesting sites occur in Nicaragua and other tropical mainland shores. The species does not nest in the U.S. (NMFS 2021i)

Habitat Olive ridleys are primarily a pelagic species and can be found as far as 2,400 mi (3,900 km) off the coast. The species is associated with relatively deep, soft-bottomed habitats inhabited by crabs and other crustaceans. They are sometimes also found in shallower benthic habitats near estuaries. (NMFS 2021i)

Diet Olive ridleys are omnivorous and consume a variety of algae, lobster, crabs, tunicates, and mollusks. Individuals can dive to depths of 500 ft (150 m) to forage on benthic invertebrates. (NMFS 2021i) 5.3.6 Occurrence Within the Action Area In a 2016 ESA Section 7 consultation with the USACE concerning installation of the LOEDs at SONGS, NMFS (2016a) found that leatherback sea turtles are more commonly found seasonally in the summer and fall along central rather than southern coastal waters of California (Benson et al. 2007). However, the species has historically been entrained in the SONGS cooling intake system (one live individual in 1994 and one dead individual in 1996; see Table A2). Olive ridley and loggerhead sea turtles also occasionally visit southern California coastal waters, including a few individuals that have been entrained at SONGS (see Table A2) and others that have been involved in other stranding events in the local vicinity of the action area (NMFS 2016a). These strandings have occurred more commonly during warmer water months and years.

Green sea turtles are the one species known to be regular residents of coastal waters in the Southern California Bight. A known persistent foraging aggregation occurs in San Diego Bay and in the Long Beach area (Eguchi et al. 2010; Crear et al. 2016). Based on genetic analyses and tracking studies conducted by NMFS Southwest Fisheries Science Center, green turtles found in southern California likely represent the endangered population of turtles breeding on the Pacific coast of Mexico. While the relationship between these aggregations is not well understood, a green sea turtle was tracked with a satellite tag in 2013 as it moved out of San Diego Bay and eventually headed north along the coast to the Long Beach area during June and July (Graham and Saunders 2013). Historically, green turtle strandings have occurred throughout the southern California coastline. SONGS has recorded 45 green sea turtle entrainments since 1984 (see Table A2). Based on this information, NMFS (2016a) generally expects that any sea turtle that may occur in the action area would most likely be a green turtle, although this species presence would still be considered infrequent.

6.0 Federally Designated Critical Habitat Critical habitat represents the habitat that contains the physical or biological features essential to the conservation of the listed species and that may require special management considerations or protection. Critical habitat may also include areas outside the geographical area occupied by the species if NMFS determines that such areas are essential for the conservation of the species. No designated critical habitat exists in the action area.

7.0 Effects of the Proposed Action SONGS ceased power operations in June 2013. As such, the only remaining effects are those associated with the shutdown and decommissioning of SONGS under its existing NRC licenses. Generally, the effects of a proposed action are all consequences to listed species or critical habitat that are caused by the proposed action, including the consequences of other activities that are caused by the proposed action. A consequence is caused by the proposed action if it would not occur but for the proposed action and it is reasonably certain to occur. Effects of the proposed action may occur later in time and may include consequences occurring outside the immediate area involved in the proposed action.

The effects of the proposed action of the shutdown and decommissioning of SONGS under its existing NRC licenses are the consequences of water withdrawal, water discharge, and removal of offshore structures. All other activities would occur on land with no identified pathways of effects to listed sea turtles. All activities associated with the shutdown and decommissioning of the facility are anticipated to be completed no later than the end of 2035.

7.1 Effects Associated with Water Withdrawal Sea turtles can become entrained at SONGS by entering one of the intake velocity caps and subsequently being drawn through one of the intake pipes. Because the intake structures begin approximately 3,200 ft (980 m) offshore, turtles are not observed entering the velocity caps.

During power operations, the intake was configured such that a sea turtle could swim into the space between the intake riser and velocity cap either out of curiosity, in search of prey, or for shelter. Once past the velocity caps, a sea turtle would have encountered the intake structures. The intake structures drew ocean water inward in a horizontal direction and then redirected the flow downward through the intake pipes. A sea turtle would have experienced an increased flow rate as it approached the center vertical riser shaft, which connects to the intake conduit. The increase in velocity and downward flow, along with the lack of light and confined space, may have caused the turtle to become disoriented and prevent it from swimming back out of the intake structure. Because the animal could not exit the intake structure, it would have been drawn through the intake pipe and ended up in the plants forebay.

Under current conditions, the flow of water entering the intake pipe is approximately 0.14 fps (0.04 m/s). This velocity is too low to affect a sea turtles ability to swim out of the intake structure to escape entrainment. Further, the LOEDs installed on the intake structures would prevent a sea turtle from entering the intake structure, as explained further below.

During operations, both SONGS intake pipes terminated at a central forebay in which entrained sea turtles could move about freely. Traveling screens within the forebay prevented turtles and other debris from progressing further into the facility. Since shutdown, SCE has modified the configuration of the intake to isolate the intake pipes from the forebay. Dilution pumps route water from the intake directly to the outfall.

Tsunami gates on the intake side and a concrete plug on the discharge side limit the area where sea turtles could end up, if entrained, to a very small area of approximately 18 ft (5 m) x 18 ft (5 m) x 10 ft (3 m) (herein referred to as intake area).

When SONGS personnel discover a live turtle in the intake area, they retrieve the turtle with a large net, examine the animal, and report it to NMFS via a NMFS Stranding Report. If the animal is healthy and uninjured, personnel release it back into the ocean.

SCE turns over animals with visible injuries to one of the animal rescue organizations in the California Marine Mammal and Sea Turtle Stranding Network, as specified by NMFS.

If the animal is dead, SCE disposes of the carcass after completing required reporting to NMFS and NRC.

In the extremely unlikely event that a sea turtle travels through one of the intake pipes, despite the LOEDs installed on the intake structures and the low flow velocity, it would have to hold its breath until it reaches the stations intake area. The amount of time a turtle can hold its breath depends on the size, condition, and species of turtle. Typical dive times for turtles under normal conditions varies by species. For example, leatherback sea turtles routinely dive for 4 to 14 minutes, while green turtles have common dive times averaging 9 to 23 minutes (NMFS 2006). In its 2006 biological opinion, NMFS (2006) determined that even under stressed conditions, a turtle would most likely be able to survive submergence through the SONGS intake pipe, which lasted approximately eight minutes during SONGS operations.

During the operational period, SONGS entrained a total of 51 sea turtles into its intake structure (see Table A2). By species, 45 were green turtles, 3 were loggerheads, 2 were leatherbacks, and 1 was an olive ridley. Of the 51 turtles, 47 were alive and healthy enough to be released back to the ocean. Two of these turtles, both green turtles, had minor abrasions and were turned over to an animal rescue organization for veterinary care. Both were eventually released.

Four turtles (two green turtles, one leatherback, and one olive ridley) were in various stages of decomposition when discovered in the forebay. None of the four animals had obvious signs of external trauma that might indicate whether the animal was injured or dead prior to being drawn into the intake structure. Both green turtle carcasses had been dead for at least a few days. The leatherback carcass was extremely decomposed and had probably been dead for weeks. While it is possible that a turtle may drown or sustain fatal injuries while transiting the intake pipes, SCE personnel check the intake structures daily for animals, so it is unlikely that a dead turtle could have remained in the forebay long enough to decompose. In its 2006 biological opinion, NMFS (2006) concluded that these turtles were most likely dead prior to entrainment.

In the 2006 biological opinion, NMFS anticipated certain levels of incidental take for the period from September 2006 through November 2022 (see Table 1). However, because SONGS ceased power operations early, it only entrained a small portion of these estimates. Based on the allowable ITS numbers, NMFS anticipated that SONGS would entrain an average of 2.6 sea turtles per year (43 total sea turtles/195 months). During the operational period following issuance of the biological opinion (from September 2006 through June 2013), SCE reported the entrainment of 15 sea turtles, which equates to approximately 2.2 sea turtles per year (15 total sea turtles/82 months). No sea turtles have been entrained since the plant ceased operations in June 2013.

Table 1. Allowable and Actual Sea Turtle Entrainment, 2006-Present Allowable Entrainment, Actual Entrainment, Species Sept 2006-Nov 2022(a)(b) Sept 2006-Present(a)(c) green 34 (4,2) 13 (0,0) leatherback 3 (1,1) 0 (0,0) loggerhead 3 (1,1) 1 (0,0) olive ridley 3 (1,1) 1 (1,0)

(a)

Entrainment is stated as x (y, z) where x = total entrainment, y = mortality, and z = serious injury. y and z are a subset of x.

(b)

Allowable levels of incidental take are specified in the ITS in Section X of the biological opinion (NMFS 2006).

(c)

No sea turtles have been entrained since the plant ceased operations in June 2013.

During power operations, SONGS withdrew over 1,600,000 gpm (2,304 mgd) of water from the Pacific Ocean. Currently, SONGS withdraws only 16,000 gpm (23 mgd). This withdrawal rate is anticipated to continue through 2035, at which time withdrawals will cease. The NRC staff used actual sea turtle entrainment numbers for the period from September 2006 through June 2013 combined with intake flow rates to calculate anticipated annual entrainment during the decommissioning period (see Table 2).

Table 2. Annual Sea Turtle Entrainment Rates During Power Operations (Actual) and Decommissioning (Estimated)

Actual Annual Entrainment Rate Estimated Annual Entrainment During Power Operations(a) Rate During Decommissioning(b)

Average 2,304 mgd 23 mgd Flow Rate Severely Severely Condition Total Dead Injured Total Dead Injured green 1.90 0 0 0.019 0 0 leatherback 0 0 0 0 0 0 loggerhead 0.15 0 0 0.001 0 0 olive ridley 0.15 0.15 0 0.001 0.001 0 (a)

Based on incidental take data over the period from September 2006-June 2013.

(b)

Calculated by multiplying the actual annual entrainment rate during power operations by the percentage of intake flow being withdrawn during the decommissioning period (e.g., 1.9 green sea turtles per year x (23 mgd/2,304 mgd) = 0.019 green sea turtles per year).

From the estimated annual entrainment rates during decommissioning, the NRC staff calculated the estimated total cumulative sea turtle entrainment during the decommissioning period (i.e., 2021 through 2035) to be 0.42 live green turtles, 0.02 live loggerheads, and 0.02 dead olive ridleys over the 22.2-year period (see Table 3). These projections are low enough to render sea turtle entrainment a discountable impact because it would be extremely unlikely for a sea turtle of any species to be entrained through December 2035. After December 2035, all SONGS-related water withdrawals from the Pacific Ocean will cease, which will wholly eliminate the potential for sea turtle entrainment. Further, these numbers, which are already close to zero, are likely overestimates because the intake velocity is now significantly lower than during operations (i.e., it has decreased from 7.42 fps (2.26 m/s) to 0.14 fps (0.04 m/s)) and because SCE installed LOEDs at the primary offshore intake structures and at the auxiliary offshore intake structures five years ago, and no sea turtles have been entrained since.

Table 3. Anticipated Total Sea Turtle Entrainment During Decommissioning, June 2013-December 2025 Entrainment(a)

Severely Total Dead Injured green 0.42 0 0 leatherback 0 0 0 loggerhead 0.02 0 0 olive ridley 0.02 0.02 0 (a)

Calculated by multiplying the estimated annual entrainment rate during decommissioning (see Table 2) by the period over which water will continue to be withdrawn to support decommissioning (e.g., 0.019 green sea turtles per year x 22.2 years = 0.42 green sea turtles).

Under current conditions, a sea turtle would only be able to enter the intake if the LOEDs were compromised in some way, such as from storm damage, or if SCE temporarily removes the LOEDs for maintenance. In the unlikely event that a sea turtle enters the intake at such a time, the turtle could freely swim back out of the intake structure and escape entrainment because of the low flow velocity. Alternatively, if the turtle swims far enough down one of the intake pipes to become disoriented, the low flow could result in the turtle remaining in the intake pipe for a period beyond its ability to hold its breath.

The turtle would then suffocate and die. Eventually, the turtles body would be drawn through the length of the intake pipe and enter the intake area where SONGS personnel could retrieve it. However, this scenario is extremely unlikely to occur because SCE has reported no sea turtle entrainment during the 8-year period since SONGS ceased operations and SCE reduced intake flow. Additionally, installation and proper maintenance of the LOEDs are requirements imposed by the SDRWQCB through the SONGS NPDES permit (SDRWQCB 2015). The NRC staff assumes that SCE would continue to comply with its NPDES permit during the decommissioning period and that, therefore, the LOEDs would remain functional and effective as long as SONGS continues to withdraw ocean water. Therefore, the combination of an extremely low intake flow velocity paired with the LOEDs appears to preclude the risk of entrainment altogether. Accordingly, it is not reasonable to expect that any sea turtles will be entrained at SONGS during the decommissioning period.

Based on the above analysis, the NRC staff finds that decommissioning-related water withdrawals represent a discountable effect to sea turtles because, based on best judgement, entrainment from such withdrawals is not expected to occur. This reasoning is consistent with NMFSs analysis for the decommissioning of Oyster Creek Nuclear Generating Station (Oyster Creek) (NMFS 2020b; see Section 7.1, Water Withdrawal, under Effects of the Action). This finding is also consistent with NMFSs (2016a) concurrence for an ESA Section 7 consultation with the USACE prior to installation of the LOEDs, in which NMFS concluded that [g]iven the construction design and material of the LOED, we expect that the risks of future entanglement and/or impingement of ESA-listed sea turtles with the LOED are discountable.

With respect to marine mammals, water withdrawal would not affect these animals because they are too large to be entrained into the ocean intake system. Whales are unlikely to occur within 0.6 mi (1 km) of shore or in waters less than 33 ft (10 m) deep (see Section 5.2.6 of this assessment) where the intake structures are located.

Guadalupe fur seals could rarely to occasionally occur in the area, but the LOEDs, which were specifically installed to prevent entrainment of marine mammals and sea turtles, preclude the risk of entrainment altogether. Therefore, water withdrawal would have no effect on listed marine mammals.

The NRC staff also considered whether prey removal caused by water withdrawal could adversely affect sea turtles or marine mammals. Prey species susceptible to impingement or entrainment are pelagic organisms that inhabit nearshore habitat. For the listed species of concern, these include schooling fish, such as mackerel, anchovies, and sardines; cephalopods; jellyfish; salps; and certain species of neritic krill (e.g., Euphausia pacifica and Thysanoessa spinifera). Prey removal would not be of concern for loggerhead, green sea, or olive ridley sea turtles or gray whales because these species consume either plants or epibenthic and benthic prey.

With respect to impingement of prey organisms, under the regulations implementing Section 316(b) of the Clean Water Act, the U.S. Environmental Protection Agency has found that one option for minimizing the adverse impacts of impingement mortality is to operate a cooling water intake structure that has a maximum through-screen design intake velocity of 0.5 fps (0.15 m/s) (40 CFR 125.94(c)). Velocity at SONGSs intake conduit is 0.14 fps (0.04 m/s) under current conditions. At this extremely low velocity, the surrounding ocean currents likely create more directional flow than the intake itself.

Mobile organisms would have sufficient swimming ability to move out of the area influenced by the intake and escape impingement. Additionally, the LOEDs would prevent entrainment of organisms too large to pass through the 9-in. by 9-in. (23-cm by 23-cm) netting. Therefore, impingement is unlikely to measurably reduce prey availability within the action area.

A low level of entrainment of smaller, less mobile organisms, such as krill, would occur.

However, krill abundance in nearshore regions, such as where the SONGS offshore intake structures are located, is generally low. During a 14-year study that modeled whale and krill hotspots in central California, Rockwood et al. (2020) found nearshore krill density to be 0-7 grams per square meter (g/m2). Krill were most abundant at around the 200-m (670-ft) isobath, which occurred roughly 40 to 60 m (130 to 200 ft) offshore within the study area. Krill hotspots were found at shelf breaks and edges.

Seasonally, krill were most abundant in June and July. Based on this information, the action area likely provides marginal foraging opportunities for blue, fin, and humpback whales. Krill densities are low, and the low flow of the intake is not expected to entrain these organisms at rates that would result in noticeable reductions in the availability of krill as prey for whales that may be transiting the action area. Therefore, entrainment is unlikely to measurably reduce prey availability within the action area.

7.2 Effects Associated with Water Discharge Section VI, Subsection B of the 2006 biological opinion addresses the effects of thermal discharges on sea turtles. In that section, NMFS notes that sea turtles would not likely be harmed by the elevated water temperatures but that elevated water temperatures could locally affect normal distribution or foraging patterns. During the decommissioning period, discharged water will no longer be heated and will be roughly the same temperature as it was when it was withdrawn (SCE 2021). Therefore, thermal discharges are not a potential effect of the proposed action and will have no effect on sea turtles or marine mammals.

Because SONGS is no longer operational, liquid radiological releases are no longer of concern. Withdrawn water is also no longer chlorinated, so the potential effect of chlorine on the marine environment is no longer of concern.

Based on the above analysis, the NRC staff finds that decommissioning-related water discharges would have no effect on sea turtles or marine mammals.

7.3 Effects Associated with Removal of Offshore Structures During removal of the intake and discharge conduits, the activities that could affect sea turtles and marine mammals include vessel collision, vessel-related pollution, dredging and seabed disturbance, underwater noise, and discharge of hydrogen sulfide gas from intake and discharge conduits. The following subsections address each of these potential effects.

Vessel Collision The proposed action would require the use of one tugboat, derrick barge, workboat, crew boat, and materials barge. During in-water structure dismantlement, vertical structures removed during dispositioning of the offshore conduits would be placed on the seafloor near the work area and within a temporary laydown area covered by the CSLC lease. The structures would be marked with temporary buoys, as needed, and then loaded onto a barge with a high-capacity crane for transport to the Port of Long Beach.

(SCE 2021)

Project-related vessels have the potential to strike, injure, or kill sea turtles or marine mammals. The infrequency of vessel traffic associated with decommissioning would limit the exposure of these animals to this risk. Other factors that affect the risk of vessel strike include vessel speed, bottom clearance, and waterway width or other obstructions.

All vessels associated with the proposed action are expected to move slowly (less than 7 knots) (SCE 2021). Slow operating speeds would reduce the risk of vessel strike for sea turtles and marine mammals because animals would have greater opportunity to avoid the vessels. There will be at least several feet of clearance between the barges and the bottom at the shallowest conditions, with more clearance in other conditions.

Given the swimming ability of sea turtles and marine mammals in the action area, animals should be able to swim under the vessel without being hit. The areas to be transited by the barges are free flowing with no obstructions; therefore, there is ample room for a sea turtle or marine mammal to avoid a vessel. Given the slow operating speeds of the vessels, the clearance between the vessels and the ocean floor, and the unimpeded geography of the action area, the NRC staff expects sea turtles and marine mammals to be able to avoid any vessels. These factors, combined with the relatively small number of vessel trips (estimated at 2 per day during peak activities), make it extremely unlikely that a project vessel will strike a sea turtle or marine mammal.

Additionally, the NRC staff is unaware of any sea turtle or marine mammal vessel-strike injuries or mortalities resulting from barge traffic in connection with SONGS construction or operations, which further supports this conclusion. NMFS (2016b, 2017, 2020) has also assessed the impacts of barge traffic, among other effects, as part of its ESA Section 7 consultations with the NRC for other projects requiring regular barge deliveries and found the potential impacts of vessel traffic on sea turtles and other mobile aquatic listed species (sturgeon) to be discountable.

The NRC staff also considered whether avoiding vessels associated with the proposed action could increase the risk of sea turtles or marine mammals being struck by non-project vessels operating in the action area. For this to occur, another vessel would have to be close enough to the project vessel such that the animals evasive movements make it such that it was less likely to avoid the nearby vessel. Given common navigational safety practices (i.e., not traveling too close to other vessels to minimize the risk of collisions), it is extremely unlikely that another vessel would be close enough such that evasive maneuvers from a sea turtle would increase its risk of being struck.

Further, SCE would implement a Marine Mammal and Sea Turtle Mitigation and Monitoring Plan that would be subject to CSLC review and approval. The plan would include the following requirements to minimize the potential effects of vessel traffic on sea turtles and marine mammals (CSLC 2019):

• Vessels shall make every effort to maintain a distance of at least 300 ft (90 m) or greater from sighted whales and 150 ft (45 m) or greater from sea turtles whenever possible.

• When an animal is sited in a vessels path or near a moving vessel and when safety permits, operators shall reduce speed and shift the engine to neutral.

• Exclusion zones, or harassment zones, would be established and monitored by qualified marine wildlife observers (MMOs).

Section 8.1 of this assessment describes this plan in further detail.

Based on the above analysis, the NRC staff finds that decommissioning-related vessel traffic represents an insignificant effect that is so small that it cannot be meaningfully measured, evaluated, or detected and would never reach the scale of a take.

Vessel-Related Pollution During offshore activities, increased vessel use in the action area would increase the risk of oil and fuel spills. Such spill could occur from fuel or hydraulic leaks on the vessels or equipment positioned on vessels or barges or during refueling, if permitted onsite. If spilled, oil would tend to stay on the surface. Intertidal and shallow subtidal habitats and associated biological communities would be at greatest risk, especially cobble substrates, because oil can penetrate the interstices between the cobble where it can persist for a long time and result in continued slow release of pollutants. Because the action area contains low intertidal and shallow subtidal, surfgrass would also be vulnerable to effects from spills.

Sea turtles and marine mammals, which transit and forage in the upper water column, would be vulnerable to spills. Because these animals breath air and because most oil floats, sea turtles and marine mammals would be exposed to oil slicks should a spill occur. When sea turtles surface in a slick, they can inhale oil and its vapors into their lungs; gulp oil into their mouths, down their throats, and into their digestive tracts while feeding; and become coated in oil, to the point of becoming entirely mired and unable to swim. Similarly, sea turtles may swim through oil drifting in the water column or disturb it in the sediments on the ocean bottom. Oil can irritate sensitive mucus membranes around the eyes, mouth, lungs, and digestive tract of sea turtles, and toxic oil compounds known as polycyclic aromatic hydrocarbons can be absorbed into vital organ tissues such as the lungs and liver (ORR 2020). Because sea turtles can hold their breath for long periods, inhaled oil has a greater chance of being absorbed into their bodies (ORR 2020). Oil compounds that get passed from mother turtles to their young can interfere with development and threaten the survival of sea turtles still developing in the eggs (ORR 2020).

Fur seals, such as the Guadalupe fur seal, rely on their thick layer of fur to insulate their bodies from the cold marine environment. Oil spills pose a threat to fur seals by affecting the ability of their fur to keep them warm. Guadalupe fur seals rarely strand in southern California. However, based on a review of its stranding reports over the last 30 years, NMFS (2021a) reports no instances of Guadalupe fur seals that have ingested oil or that have an oiled pelage.

Whale interactions with oil spills are not well documented. Oil has rarely been observed on whales. Marine mammals thick layer of blubber may have protective properties when animals are exposed to oil. Large oil spills, however, likely have detrimental population-level effects. For instance, research studies indicate that a pod of killer whales (Orcinus orca) in Prince William Sound, Alaska, decreased steadily and significantly in size following the 1989 Exxon Valdez spill (NOAA 2021).

Indirect effects of oil spills include harming or killing prey and forage of sea turtles and marine mammals, including fish, cephalopods, crabs and other crustaceans, jellyfish, seagrass, and algae. Additionally, if oil kills the sargassum grass where young sea turtles live, those turtles lose their shelter and source of food and are forced to find suitable habitat elsewhere, which makes them more vulnerable to predators and uses more energy. (ORR 2020)

The number of large and medium oil spills has decreased significantly over the last few decades. In the 2010s, the yearly average number of large spills (greater than 700 tons) and medium spills (7-700 tons) recorded globally was 1.8 and 4.5, respectively. In 2020, no large spills occurred, and three medium spills occurred, none of which were in the U.S.

Because the action area is relatively small, if spills occur, sea turtles and marine mammals could avoid the affected area until the spill is remediated. Although the likelihood of a significant spill is low, the effects of a spill on sea turtles, marine mammals, their prey, and their habitat could be significant. To avoid or minimize the potential effects of spills on sea turtles, marine mammals, and other marine life, SCE (2021) would implement an Offshore Spill Response Plan during offshore activities.

Implementation of this plan, as well as other appropriate best management practices, would minimize the potential for spills and ensure that appropriate clean-up actions are taken.

Based on the above analysis, the NRC staff finds that vessel-related pollution represents a discountable effect because oil spills are very unlikely to occur.

Dredging and Seabed Disturbance Offshore activities would involve minor dredging and debris removal, anchoring, and use of three to four temporary laydown areas on the seafloor within the CSLC lease area.

These activities would support the removal or reconfiguration of 45 structures (23 manhole access port structures, two primary offshore intake structures, two auxiliary offshore intake structures, 12 diffuser risers, a fish return conduit opening, and five buoy anchors) and would last approximately 4 months. Turbid conditions would also result at any one removal location for periods of no more than 3 days. (SCE 2021)

Soft sediment habitat would be removed around each of the 39 vertical structures plus the fish return conduit to enable diver access to vertical structure cutting points. Material would be either removed and side-cast on the seabed within 15 to 20 ft (4.6 to 6 m) of the excavation area by a long reach excavator, or material would be suction dredged by divers operating a tethered hose and deposited within the discharge conduit. Removal of buoy anchors would also result in the disturbance of a small amount (135 ft2 or 12 m2) of soft sediment habitat. SCE estimates that the total volume of removed or disturbed material would be 1,159 yds3 (886 m3) over an area of 1.075 ac (0.43 ha) of seabed.

The largest volume of removed material at any one location would be 229 yds3 (175 m3) from an 0.43-ac (0.17-ha) area adjacent to each of the two primary offshore intakes structures. The area of affected seabed would vary in size according to the type of structure being removed. (SCE 2021)

During dredging, sea turtles are not known to be vulnerable to entrainment in dredge heads because sea turtles are able to avoid the relatively small intake size and low intake velocity associated with this type of dredge. Sea turtle entrainment is, therefore, discountable because it is extremely unlikely to occur based on the lack of documented interactions between sea turtles and dredges. These assumptions and conclusions are further supported by NMFSs (2018) analysis of dredging during a 2018 programmatic ESA Section 7 consultation with the Federal Highway Administration, as well as NMFSs (2020) conclusions regarding dredging in connection with the decommissioning of Oyster Creek. Marine mammals would not be susceptible to entrainment based on this same logic. Dredging also has the potential to affect sea turtles and marine mammals indirectly through impacts on prey, forage, or other habitat features. Dredging of any kind results in the direct removal of benthic habitat along with infaunal and epifaunal organisms of limited mobility. Thus, dredging can be expected to cause short-term reductions in biomass of benthic organisms. Dredging also creates sediment plumes that increase water turbidity, which can adversely affect aquatic biota and create short-term decreases in habitat quality during and after dredging. Turbidity primarily affects liquid-breathing organisms, such as fish and shellfish, as well as aquatic plants because turbid conditions typically decrease photosynthetic capabilities. Turbidity levels associated with the sediment plumes of cutterhead dredges typically range from 11.5 to 282.0 mg/L with decreasing concentrations at greater distance from the dredge head (Nightingale and Simenstad 2001). Studies of benthic community recovery following dredging indicate that species abundance and diversity can recover within several years of dredging (Michel et al. 2013).

Sea turtles and marine mammals prey on a variety of pelagic, epibenthic, and benthic organisms, some of which could be affected by dredging. Loggerheads are primarily carnivorous and eat sea urchins, horseshoe crabs, clams, mussels, and other benthic invertebrates. Juvenile green sea turtles are omnivorous and eat insects, crustaceans, seagrasses, algae, and worms, while adult green turtles are herbivores and restrict their diets to seagrasses and algae. Leatherbacks primarily eat jellyfish and other coelenterates that inhabit the water column in the open ocean and pelagic colonial tunicates. Olive ridley turtles eat crabs, mollusks, gastropods, fish, fish eggs, and algae.

Pelagic prey (e.g., squid and jellyfish) would be largely unaffected because dredging primarily disrupts the lower portion of the water column and substrates. Gray whales consume a range of benthic and epibenthic invertebrates. Benthic and epibenthic prey (e.g., sea urchins, horseshoe crabs, clams, and mussels) may be susceptible to entrainment into the dredge head. Larger individuals or those that are farther from the dredge head could move away from the suction flow field to avoid being entrained. All prey in the dredge area, including seagrasses and algae, could also be affected by other factors, such as sedimentation and turbidity. However, as explained above, the local benthic community would likely recover within a few years such that any local reductions in benthic biomass or other observable impacts would be relatively short term. In summary, the NRC staff concludes that the impacts of dredging on sea turtle and marine mammal prey and forage would be minimal for the following reasons: dredging would only occur once over the course of the proposed action; the dredge area contains a small portion of the available prey base for the listed species present in the action area; the dredge area does not provide habitat for many preferred prey and forage; and the local benthic community would recover relatively quickly.

Limited information is available on the effects of increased turbidity on sea turtles and marine mammals. Because these animals breath air, they are not subject to the same potential respiratory effects of high turbidity as fish and shellfish. Sea turtles and marine mammals are most likely to be affected by turbidity if dredging-induced sedimentation plumes block passage or affect normal behaviors or if sediment settles on top of existing substrates and affects prey (NMFS 2018; NMFS 2021). Because sea turtles and marine mammals are highly mobile, individuals are likely to be able to avoid any sediment plumes caused by dredging. Sediment plumes and associated turbidity would also be short-term effects that would primarily be experienced during operation of the dredge and would end soon after dredging ceased. Sedimentation could also affect benthic and epibenthic prey, including mollusks and crustaceans. However, these individuals could avoid the plume or uncover themselves from any sedimentation experienced during dredging such that these impacts would be negligible and short term and would not measurably affect the available prey base within the dredged area. Based on the above discussion, the NRC staff concludes that turbidity and sedimentation associated with dredging would not noticeably or measurably affect sea turtles or marine mammals or their prey or forage.

Additionally, in association with dredging activities, SCE (2021) would implement a Conduit Work Plan, a Dredging Plan, an Anchoring Plan, and a Turbidity Monitoring Plan to reduce localized and short-term effects.

Based on the above analysis, the NRC staff expects that all effects associated with dredging on sea turtles and marine mammals would be too small to be meaningfully measured or detected and would, therefore, be insignificant. Additionally, the NRC staff is unaware of any dredging-related effects on sea turtles or marine mammals during the SONGS construction and operation periods, which further supports this conclusion.

NMFS (2017, 2020) has also assessed the impacts of dredging, among other effects, as part of its ESA Section 7 consultation with the NRC for other projects and found the potential impacts of dredging on sea turtles to be discountable.

Underwater Noise Underwater noise would be generated from vessel engines, excavation, dredging, and side-casting operations, as well as from saw cutting during removal of manhole access port structures, primary offshore intake structures, auxiliary offshore intake structures, and diffuser ports. The most concentrated noise-generating activities would take up to five months to complete, during which time underwater noise would be generated on an intermittent basis. Saw cutting would cause the greatest underwater noise disturbances.

These noise-generating activities are likely to be intermittent and would only occur during discrete periods of dismantlement lasting several months. (SCE 2021)

Project-related vessel traffic (e.g., crew and tugboats) could potentially expose sea turtles and marine mammals to elevated underwater noise levels. Vessel noise is a combination of narrowband tones at specific frequencies and broadband noise, which are roughly related to a vessels size and speed. Noise associated with vessel traffic would be limited to short durations while transporting crews and equipment. The total duration of both types of operating vessels would likely be less than 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> per day.

(SCE 2021)

Sound levels from vessel activity could exceed National Oceanic and Atmospheric Administration underwater acoustic thresholds for non-impulsive, continuous noise (120 decibels Root Mean Square (dBrms); threshold used for marine mammals, and for sea turtles in the absence of formal criteria). However, noise generated by supply or crew vessels would be like noise generated by other vessels that routinely transit the area. Any increase in ambient noise levels due to the proposed action would result in a minor increase in already-existing noise levels. Noise from vessel traffic would be comparable to noise-generating activities in other coastal areas where sea turtles and marine mammals co-occur. (SCE 2021)

Data from acoustic monitoring devices installed before and during offshore dismantlement activities would be used to establish Level B behavioral harassment zones of influence where received underwater sound pressure levels are higher than 160 dBrms and 120 dBrms for impulsive noise sources (e.g., impact pile driving) and non-impulsive noise sources (e.g., vibratory pile driving, mechanical dismantling),

respectively. SCE will employ CLSC- and NMFS-approved MMOs during offshore decommissioning activities. The MMOs will use the behavioral harassment zones to determine whether stop work procedures need to be implemented for sea turtles and marine mammals active in the area. MMOs have the authority to halt activities with the potential to generate high-amplitude impulse or continuous noise when sensitive species are near noisy activities to allow sensitive species time to depart the area under reasonably natural behavior. (SCE 2021)

Further, SCE would implement a Marine Mammal and Sea Turtle Mitigation and Monitoring Plan that would be subject to CSLC review and approval. The plan would include a risk analysis (likelihood and consequence) of noise effects to sea turtles and marine mammals based on the most recent activity plans. The plan would also require SCE to develop an acoustic monitoring strategy to potentially include installation of acoustic monitoring devices, establishment of behavioral harassment zones, and protocol for pausing project activities that generate sufficient noise to exceed limits established by NMFS while vulnerable marine organisms are in the established harassment zones. Section 8.1 of this assessment describes this plan in further detail.

Based on the above analysis, the NRC staff finds that decommissioning-related noise represents an insignificant effect that is so small that it cannot be meaningfully measured, evaluated, or detected and would never reach the scale of a take.

Discharge of Hydrogen Sulfide (H2S) Gas from Intake and Discharge Conduits The removal of the primary and auxiliary offshore intake structures and diffuser ports from each of the two discharge conduits would release water that had been contained inside the conduits. If the water inside the conduits has remained stagnant for a long time, the oxygen in that water could become depleted and anaerobic conditions could result. In such conditions, bacteria that produce H2S gas could thrive. Several factors would influence whether optimal conditions form to allow these bacteria to grow, including the water temperature inside the conduits, the amount of biological material in the conduit water, the level of biofouling (e.g., mussel and barnacle growth) on the conduits, and the time between when use of the conduits is permanently discontinued and when the conduits are ultimately removed. (SCE 2021)

Upon removal of the conduits, water from within the conduits would mix with surrounding ocean water. If the water from within the conduits contains H2S gas from anaerobic bacteria growth, this gas would also be released and would rise to the oceans surface.

Any release of H2S gas is likely to occur very quickly (within minutes). Marine life that interacts with this gas could experience adverse effects, including immediate or latent mortality, because the water would not contain high enough concentrations of oxygen and marine organisms could effectively suffocate. However, because sea turtles and marine mammals breath air, these animals are unlikely to be directly affected by the oxygen depletion that could occur with H2S releases. Additionally, the likelihood that sea turtles or marine mammals would be in the area of H2S release is low because vessel traffic and other in-water disturbances would be occurring simultaneously, which would temporarily deter these animals from transiting the area. As previously described, SCE would employ MMOs during offshore decommissioning activities that would have the authority to halt work activities if a sea turtle or marine mammal is observed within established behavioral harassment zones.

Sea turtles and marine mammals could experience indirect effects if gaseous releases kill prey species. However, such effects would be temporary and localized and would not be expected to measurably reduce available food resources in the action area.

To minimize the potential impacts of H2S releases, SCE will prepare and implement an H2S Gas Control Plan (CSLC 2019). As part of this plan, prior to accessing any enclosed spaces within the conduits, an H2S inspector would perform an H2S Gas Risk Assessment to assess the level of risk from gaseous build up and determine if H2S gas occurs at sufficient levels to pose a hazard to sea turtles, marine mammals, and other marine life. SCE would provide the completed assessment to the CSLC, CCC, and other agencies, as appropriate, for review no less than 60 days prior to conducting any conduit decommissioning work. In consultation with these agencies, SCE would determine whether further actions should be taken to mitigate or eliminate potential impacts to aquatic life, as appropriate, prior to or during conduit removal. In its final environmental impact report concerning SONGS decommissioning, the CSLC (2019) found that with the implementation of the H2S Gas Control Plan and any associated mitigation, the potential for impacts to listed species from H2S gas release would be less-than-significant. Further, SCE would implement a Marine Mammal and Sea Turtle Mitigation and Monitoring Plan that would be subject to CSLC review and approval.

Section 8.1 of this assessment describes this plan in further detail. Based on the above analysis, the NRC staff finds that discharge of H2S gas from intake and discharge conduit removal represents a discountable effect because SCE would take steps to ensure that such releases are unlikely to occur at levels that could harm sea turtles or marine mammals or their prey or forage.

8.0 Mitigation Strategies 8.1 Marine Mammal and Sea Turtle Mitigation and Monitoring Plan As part of the decommissioning process, SCE will prepare and implement a Marine Mammal and Sea Turtle Mitigation and Monitoring Plan. This plan will be subject to CSLC review and approval. As described on pages 4.4-65 and 4.4-66 of the CSLCs (2019) Final Environmental Impact Report for the SONGS Units 2 & 3 Decommissioning Project, the plan will consist of the following (emphasis in original).

MM BIO-11: Marine Mammal and Sea Turtle Mitigation and Monitoring Plan.

The Applicant or its contractor shall prepare a Marine Mammal and Sea Turtle Mitigation and Monitoring Plan. The purpose of the Plan is to ensure that no harassment of marine mammals or other marine life occurs during Proposed Project activities. The Plan, which may be a part of a National Marine Fisheries Service (NMFS) and U.S. Fish and Wildlife Service (USFWS) consultation under the Marine Mammal Protection Act, shall include:

• A description of the work activities including vessel size, activity types and locations, and Proposed Project timeframes.

• A risk analysis (likelihood and consequence) of noise effects to marine mammals and sea turtles based on the most recent activity plans.

• The qualifications, number, location, and roles/authority of dedicated marine wildlife observers (MMOs). A minimum of two MMOs, approved by California State Lands Commission (CSLC) and NMFS staffs, shall be placed on major support vessels.

• The distance, speed, and direction transiting vessels shall maintain when in proximity to a marine mammal or turtle, as follows:

o Vessel operators shall make every effort to maintain a distance of at least 300 feet from sighted whales, and 150 feet or greater from sea turtles or smaller cetaceans whenever possible.

o When small cetaceans are sighted while a vessel is underway (e.g.,

bow riding), vessel operators shall attempt to remain parallel to the animals course. When paralleling whales, vessels shall operate at a constant speed that is not faster than the whales and shall avoid excessive speed or abrupt changes in direction until the cetacean has left the area.

o Per NMFS recommendations, and when safety permits (i.e., excluding during poor sea and weather conditions, thereby ensuring safe vessel maneuverability under those special conditions), vessel speeds shall not exceed 11.5 miles per hour (10 knots) when mother/calf pairs, groups, or large assemblages of cetaceans (greater than five individuals) are observed near an underway vessel. A single cetacean at the surface may indicate the presence of submerged animals in the vicinity; therefore, prudent precautionary measures, such as decreasing speed and avoiding sudden changes in direction, should always be exercised. The vessel shall route around the animals, maintaining a minimum distance of 300 feet. Whales may surface in unpredictable locations or approach slowly moving vessels.

When an animal is sighted in the vessels path or in close proximity to a moving vessel and when safety permits, operators shall reduce speed and shift the engine to neutral. Vessel operators shall not engage the engines until the animals are clear of the area.

o Support vessels (i.e., barge tows) shall not cross directly in front of migrating whales, other threatened or endangered marine mammals, or sea turtles.

o Vessels shall not separate female whales from their calves or herd or drive whales. If a whale engages in evasive or defensive action, support vessels shall drop back until the animal moves out of the area.

• Observation recording procedures and reporting requirements in the event of an observed impact to marine wildlife. Collisions with marine wildlife shall be reported promptly to the federal and state agencies listed below pursuant to each agencys reporting procedures.

National Marine Fisheries Service Southwest Region Stranding Coordinator Long Beach, CA 90802 Phone: (562) 980-3230 or (562) 506-4315 (24-hour cell)

California State Lands Commission Mineral Resources Management Division Long Beach, CA 90802 Phone: (562) 590-5201

• An acoustic monitoring strategy. If underwater sound pressure levels are thought to exceed limits established by NMFS, a marine acoustics specialist shall install acoustic monitoring devices before saw cutting occurs to monitor and establish Level B behavioral harassment zones, which shall be enforced by qualified marine wildlife observers. The strategy shall also include the pausing of activities that generate sufficient noise to exceed limits established by NMFS while vulnerable marine organisms are in the established harassment zones.

This mitigation is subject to NMFS and USFWS consultation. The Plan shall be submitted to CSLC staff a minimum of 30 days prior to the implementation of offshore work.

8.2 Biological Opinion Monitoring and Reporting The 2006 biological opinion requires SCE to monitor for sea turtle entrainment.

Specifically, T&C 1 states:

Inspection of the CWS [cooling water structure] (area between the curtain wall and bar racks at DCPP [Diablo Canyon] and forebay at SONGS) shall be conducted every twelve hours. Times of inspections, including those when no turtles were sighted, must be recorded.

T&C 7 states:

Every effort should be made to observe the area around the CWS of the DCPP and SONGS facilities. Any sea turtle sighted in the vicinity of either plant should be reported to NMFS in an annual report.

The remaining T&Cs specify training requirements for SCE personnel involved in sea turtle monitoring and rescue; how SCE should respond to live or dead entrained sea turtles, including coordination with the California Sea Turtle Stranding Network (CSTSN) for treatment of injured turtles; and reporting requirements, including the preparation of an annual report to NMFS by February 1 of each year.

These requirements remain in effect until either the current biological opinion expires (in November 2022) or NMFS issues a new biological opinion that supersedes the current opinion.

8.3 Other Mitigation and Monitoring Plans SCE would implement several additional monitoring and mitigation plans to ensure that environmental impacts are minimized. These plans are discussed throughout this assessment. The CSLCs (2019) Final Environmental Impact Report for the SONGS Units 2 & 3 Decommissioning Project discusses the requirements of each of these plans in detail. The relevant mitigation plans are as follows:

• APM-17: Offshore Spill Response Plan (CSLC 2019, page 4.4-54)

• MM BIO-9: Hydrogen Sulfide (H2S) Gas Control Plan (CSLC 2019, page 4.4-55)

• MM BIO-10: Anchoring Plan (CSLC 2019, page 4.4-60)

• APM-9: Conduit Work Plan (CSLC 2019, page 4.4-59)

• APM-15: Dredging Plan (CSLC 2019, page 4.9-23)

• APM-16: Turbidity Monitoring Plan (CSLC 2019, page 4.9-23) 9.0 Cumulative Effects Cumulative effects are those effects of future State or private activities, not involving Federal activities, that are reasonably certain to occur within the action area of the Federal action subject to consultation (50 CFR 402.02). When formulating biological opinions, NMFS considers cumulative effects when determining the likelihood of jeopardy or adverse modification.

According to Section VII of the 2006 biological opinion, cumulative effects in the action area include incidental take of sea turtles during fishing operations, vessel collisions, ingestion of debris, pollution, and natural disasters.

Commercial and recreational vessels will continue to operate in the action area in the future. Sea turtles and marine mammals will continue to be injured or killed from interactions with these vessels. Noise levels associated with vessels may also disturb sea turtles and marine mammals and directly or indirectly affect their normal foraging, breeding, or migratory behavior. (NMFS 2006)

Marine debris and pollution from various sources pose a threat to sea turtles and marine mammals in the action area. CSTSN data and necropsy results demonstrate that sea turtles off the California coast become entangled in and ingest marine debris. CSTSN data has shown that turtles have been affected by derelict fishing gear, plastics, wood, and paper. Additionally, chemical contaminants may affect sea turtle reproduction and survival; however, specific impacts remain relatively unclear. (NMFS 2006)

Coastal communities and continued development near SONGS will continue to contribute to debris and contaminants entering the waters of the action area through stormwater runoff and other non-point sources (NMFS 2006).

10.0 Conclusions Based on the NRC staffs analysis presented in this biological assessment, the staff makes the following conclusions.

Summary of Effects The NRC staff finds that all potential effects of the proposed action are insignificant or discountable, as summarized below.

• Effects Associated with Water Withdrawal: Entrainment of sea turtles and marine mammals because of the proposed action represents a discountable effect because, based on best judgement, entrainment is not expected to occur.

Water withdrawals during the decommissioning period will constitute a small fraction (i.e., approximately 2 percent) of the volume of water that the facility withdrew during power operations and will cease by 2035. Intake velocity is now significantly lower than during operations and SCE has installed LOEDs at the primary offshore intake structures and at the auxiliary offshore intake structures.

No sea turtles have been entrained since the LOEDs were installed, and no marine mammals have been entrained since SONGS began operating. Water withdrawal is also not expected to remove prey species at rates that would measurably reduce the availability of these organisms as food for sea turtles or marine mammals.

• Effects Associated with Water Discharge: Decommissioning-related water discharges would have no effect on sea turtles or marine mammals. Although water would continue to be discharged during the decommissioning period, it would no longer be heated or chlorinated. Because SONGS is no longer operational, liquid radiological releases are no longer of concern.

• Effects Associated with Removal of Offshore Structures: Vessel collisions with sea turtles or marine mammals are extremely unlikely to occur because vessels would operate at slow speeds within the action area, sufficient clearance exists between the vessels and the ocean floor, and a relatively small number of vessel trips would be required to support decommissioning activities. Vessel-related pollution in the form of oil and fuel spills are very unlikely to occur, and SCE would implement work plans for spill prevention and clean-up. Dredging and seabed disturbance effects would be short term and are unlikely to result in measurable or detectable impacts. Underwater noise would be short term, and SCE would establish behavioral harassment zones in which it would stop work if vulnerable sea turtles or marine mammals are present within these zones. The discharge of H2S gas from intake and discharge conduits represents a discountable effect because SCE would take steps to ensure that such releases are unlikely to affect sea turtles or marine mammals. These effects of offshore activities would be further minimized by SCEs implementation of a Marine Mammal and Sea Turtle Mitigation and Monitoring Plan, as well as several other activity-specific work plans and monitoring, and the employment of CLSC- and NMFS-approved MMOs during potentially disruptive activities.

10.1 Guadalupe Fur Seal Based on the analysis in this biological assessment, the NRC staff concludes that the proposed action may affect but is not likely to adversely affect the Guadalupe fur seal.

10.2 Blue Whale Based on the analysis in this biological assessment, the NRC staff concludes that the proposed action may affect but is not likely to adversely affect the blue whale.

10.3 Fin Whale Based on the analysis in this biological assessment, the NRC staff concludes that the proposed action may affect but is not likely to adversely affect the fin whale.

10.4 Humpback Whale, Central American and Mexico DPSs Based on the analysis in this biological assessment, the NRC staff concludes that the proposed action may affect but is not likely to adversely affect the Central American or Mexico DPSs of the humpback whale.

10.5 Gray Whale, Western North Pacific DPS Based on the analysis in this biological assessment, the NRC staff concludes that the proposed action may affect but is not likely to adversely affect the Western North Pacific DPS of the gray whale.

10.6 Loggerhead Sea Turtle, North Pacific Ocean DPS Based on the analysis in this biological assessment, the NRC staff concludes that the proposed action may affect but is not likely to adversely affect the North Pacific Ocean DPS of the loggerhead sea turtle.

10.7 Green Sea Turtle, East Pacific DPS Based on the analysis in this biological assessment, the NRC staff concludes that the proposed action may affect but is not likely to adversely affect the East Pacific DPS of the green sea turtle.

10.8 Leatherback Sea Turtle Based on the analysis in this biological assessment, the NRC staff concludes that the proposed action may affect but is not likely to adversely affect the leatherback sea turtle.

10.9 Olive Ridley Sea Turtle Based on the analysis in this biological assessment, the NRC staff concludes that the proposed action may affect but is not likely to adversely affect the olive ridley sea turtle.

11.0 Relevant Reports Several reports are available that evaluate the impacts of SONGS decommissioning on the environment. These reports are listed and summarized below.

Additionally, the NRC will conduct a NEPA review at the license termination stage. SCE must decommission the SONGS site within 60 years of the permanent cessation of operations unless SCE receives permission to the contrary. SCE remains accountable to the NRC until it completes decommissioning and the NRC terminates the license. To terminate its license, SCE must submit a license termination plan (LTP) to the NRC for review and approval at least two years before the intended termination date. Licensees typically submit such a plan near the end of the decommissioning process. At this time, SCE has not yet developed the LTP for SONGS. However, according to SCEs current decommissioning schedule, SCE would be required to submit the LTP to the NRC by the end of 2049. Once the NRC receives the LTP, the NRC staff will conduct safety and environmental reviews. Typically, the environmental review is documented in an environmental assessment. The staff will also conduct additional ESA Section 7 consultations at that time, as appropriate. Following its review and approval of the LTP, the NRC will issue an amendment to the facility license to incorporate the LTP.

SONGS Post-Shutdown Decommissioning Activities Report In May 2020, SCE submitted an updated PSDAR to the NRC in accordance with termination of license requirements at 10 CFR 50.82. The PSDAR includes a description of the planned decommissioning activities; a schedule for completing such activities; a site-specific decommissioning cost estimate, including the projected cost of managing irradiated fuel and site restoration; and an evaluation of the environmental impacts of decommissioning activities. This submittal is cited as SCE 2020 in this biological assessment and can be accessed online at:

https://www.nrc.gov/docs/ML2013/ML20136A339.pdf.

SCE Response to Request for Additional Information to Support Endangered Species Act Consultation In April 2021, SCE submitted additional information to the NRC to support the NRCs development of a biological assessment and its reinitiation of ESA Section 7 consultation in connection with the SONGS decommissioning. This submittal describes the action area, identifies federally listed species within the action area, and evaluates the effects of decommissioning on those species. This submittal is cited as SCE 2021 in this biological assessment and can be accessed online at: https://www.nrc.gov/docs/

ML2110/ML21104A066.pdf.

In October 2021, SCE submitted a technical memorandum to the NRC clarifying the above submittal. This memorandum can be accessed online at:

https://www.nrc.gov/docs/ML2128/ML21280A108.pdf.

Final Environmental Impact Report for the SONGS Decommissioning Project In February 2019, the CSLC prepared a final environmental impact report (EIR) in accordance with CEQA that evaluated the impacts of the SONGS decommissioning.

State law requires the CSLC to perform a CEQA review prior to deciding on a new lease for the offshore land containing the intake and discharge conduits. The EIR evaluates in detail the decontamination and dismantlement of most onshore above-grade structures, including the containment buildings, and CSLC lease offshore activities, which include the disposition of the offshore intake and discharge conduits and associated structures that are part of the CSLC lease facilities. The EIR is cited as CSLC 2019 in this biological assessment and can be accessed online at: https://www.slc.ca.gov/ceqa/san-onofre/.

SONGS Environmental Impact Evaluation: Decommissioning Supplemental Environmental Analysis In January 2014, Enercon Federal Services prepared an evaluation to support SCEs preparation of the PSDAR. This evaluation includes detailed analysis of all potential onshore and offshore impacts of the SONGS decommissioning. This evaluation is cited as Enercon 2014 in this biological assessment and can be accessed online at:

https://www.nrc.gov/docs/ML2110/ML21105A714.pdf.

12.0 Literature Cited References with Agencywide Documents Access and Management System (ADAMS) accession numbers can be accessed through the NRCs web-based ADAMS search engine at https://adams.nrc.gov/wba/. To retrieve a document, click on the Advanced Search tab, choose the following criteria under Document Properties: Accession Number in the Property box and is equal to in the Operator box, and insert the ADAMS accession number of the document in the Value box.

40 CFR Part 125. Code of Federal Regulations, Title 40, Protection of Environment, Part 122, EPA Administered Permit Programs: The National Pollutant Discharge Elimination System.

50 CFR Part 402. Code of Federal Regulations, Title 50, Wildlife and Fisheries, Part 402, Interagency CooperationEndangered Species Act of 1973, as Amended.

35 FR 8491. U.S. Fish and Wildlife Service. Part Conservation of Endangered Species and Other Fish or Wildlife (First List of Endangered Foreign Fish and Wildlife as Appendix A). Federal Register 35(106):8491-8498. June 2, 1970.

43 FR 32800. National Marine Fisheries Service. Listing and Protecting Loggerhead Sea Turtles as Threatened Species and Populations of Green and Olive Ridley Sea Turtles as Threatened Species or Endangered Species." Federal Register 43(146):32800-32811. July 28, 1978.

50 FR 51252. National Marine Fisheries Service. Threatened Fish and Wildlife; Guadalupe Fur Seal. Federal Register 50(241):51252-51258.

59 FR 31094. National Marine Fisheries Service. Endangered and Threatened Wildlife and Plants; Final Rule to Remove the Eastern North Pacific Population of the Gray Whale From the List of Endangered Wildlife. Federal Register 59(115):31094-31095.

June 16, 1994.

76 FR 58868. National Marine Fisheries Service. Determination of Nine Distinct Population Segments of Loggerhead Sea Turtles as Endangered or Threatened; Final Rule. Federal Register 76(184):58868-58952. September 22, 2011.

81 FR 20058. National Marine Fisheries Service. Final Rule To List Eleven Distinct Population Segments of the Green Sea Turtle (Chelonia mydas) as Endangered or Threatened and Revision of Current Listings Under the Endangered Species Act; Final Rule. Federal Register 81(66):20058-20090. April 6, 2016.

81 FR 62259. National Marine Fisheries Service. Identification of 14 Distinct Population Segments of the Humpback Whale (Megaptera novaeangliae) and Revision of Species-Wide Listing; Final Rule. Federal Register 81(174):62259-62320. September 8, 2016.

81 FR 93639. National Marine Fisheries Service. Identification of 14 Distinct Population Segments of the Humpback Whale and Revision of Species-Wide Listing; Final Rule.

Federal Register 81(245):93639-93641. December 21, 2016.

85 FR 48332. National Marine Fisheries Service. Endangered and Threatened Wildlife; 12-Month Finding on a Petition To Identify the Northwest Atlantic Leatherback Turtle as a Distinct Population Segment and List It as Threatened Under the Endangered Species Act. Federal Register 85(154):48332-48421. August 10, 2020.

Barlow J, Forney KA. 2007. Abundance and population density of cetaceans in the California Current ecosystem. Fishery Bulletin 105:509-526.

Barnes R., Hughes R. 1998. An Introduction to Marine Ecology. Blackwell Scientific Publications. Oxford, England.

Becker EA, Forney KA, Ferguson MC, Barlow J, Redfern JV. 2012. Predictive modeling of cetacean densities in the California Current ecosystem based on summer/fall ship surveys in 1991-2008. U.S. Department of Commerce, NOAA Technical Memorandum NOAA-TM-NMFS-SWFSC-499. 45 pp. Available at

<https://repository.library.noaa.gov/view/noaa/4470> (accessed October 21, 2021).

Benson SR, Forney KA, Harvey JT, Caretta JV, Dutton PH. 2007. Abundance, Distribution, and Habitat of Leatherback Turtles (Dermochelys coriacea) off California, 1990-2003. Fishery Bulletin 105:337-347.

[CDFW] California Department of Fish and Wildlife. 2013. Status of the Fisheries Report: An Update Through 2011. Report to the Fish and Game Commission as directed by the Marine Life Management Act of 1998. Available at

<https://wildlife.ca.gov/Conservation/Marine/Status#28027677-status-of-the-fisheries-report-through-2011> (accessed August 23, 2021).

Crear DP, Lawson DD, Seminoff JA, Eguchi T, LeRoux RA, Lowe CG. 2016. Seasonal Shifts in the Movement and Distribution of Green Sea Turtles Chelonia mydas in Response to Anthropogenically Altered Water Temperatures. Marine Ecology Progress Series 548:219-232.

[CSLC] California State Lands Commission. 2019. Final Environmental Impact Report for the San Onofre Nuclear Generating Station (SONGS) Units 2 & 3 Decommissioning Project. February 2019. Available at <https://www.slc.ca.gov/ceqa/san-onofre/>

(accessed August 3, 2021).

[CSU-LB] California State University Long Beach. 2021. Southern California Bight Oceanography Circulation. Available at <https://www.csulb.edu/geological-sciences/southern-california-bight-oceanography/circulation> (accessed August 23, 2021).

[Enercon] Enercon Federal Services. 2014. SONGS Units 2 and 3 Environmental Impact Evaluation: Decommissioning Supplemental Environmental Analysis. Contractor Project No.: SCE-Q13-J001. Revision 0. January 29, 2014. 297 pp. ADAMS Accession No. ML21105A714.

[ESA] Endangered Species Act of 1973, as amended. 16 U.S.C. § 1531 et seq.

Eguchi T, Seminoff JA, LeRoux RA, Dutton PH, Dutton DL. 2010. Abundance and Survival Rates of Green Turtles in an Urban Environment: Coexistence of Humans and an Endangered Species. Marine Biology 157:1869-1877.

Falcone EA, Schorr GS. 2013. Distribution and Demographics of Marine Mammals in SOCAL Through Photo-Identification, Genetics, and Satellite Telemetry: A Summary of Surveys Conducted 1 July 2012-30 June 2013. Naval Postgraduate School Technical Report NPS-OC-14-002CR. Available at <https://calhoun.nps.edu/bitstream/handle/

10945/39523/NPS-OC-14-002CR.pdf?sequence=1&isAllowed=y> (accessed October 25, 2021).

Graham S, Saunders B. 2013. San Diego Bay Green Sea Turtle Monitoring Satellite Tag Progress Report. Space and Naval Warfare Systems Center Pacific. July 2013.

Gruber D, Ahlstrom E, Mullin M. 1982. Distribution of Ichthyoplankton in the Southern California Bight. California Cooperative Oceanic Fisheries Investigations Report, Vol.

XXIII. Available at <http://calcofi.org/publications/calcofireports/v23/

Vol_23_Gruber_etal.pdf> (accessed August 23, 2021).

Holbrook S, Carr M, Schmitt R, Coyer J. 1990. Effect of Giant Kelp on Local Abundance of Reef Fishes: The Importance of Ontogenetic Resource Requirements.

Bulletin of Marine Science 47(1): 104-114.

[ITOPF] International Tanker Owners Pollution Federation. 2020. Oil Tanker Spill Statistics 2020. 20 pp. Available at <https://www.itopf.org/knowledge-resources/documents-guides/oil-tanker-spill-statistics-2020/> (accessed August 23, 2021).

Lavenberg R, Mcgowen G, Jahn A, Petersen J, Sciarrotta T. 1986. Abundance of Southern California Nearshore Ichthyoplankton: 1978-1984. California Cooperative Oceanic Fisheries Investigations Report, Vol. XXVII. Available at

<http://calcofi.org/publications/calcofireports/v27/Vol_27_Lavenberg_etal.pdf> (accessed August 23, 2021).

[MBC] MBC Applied Environmental Sciences. 2017. Status of the Kelp Beds in 2016:

Ventura, Los Angeles, Orange, and San Diego Counties. Prepared for the Central Region Kelp Survey Consortium and Region Nine Kelp Survey Consortium. 91 pp.

Available at <http://kelp.sccwrp.org/reports.html> (accessed August 24, 2021).

McCue LM, Fahy CC, Greenman J, Wilkinson K. 2021. Status Review of the Guadalupe Fur Seal (Arctocephalus townsendi). 95 pp. National Marine Fisheries Service, Protected Resources Division, West Coast Region. Available at

<https://media.fisheries.noaa.gov/2021-07/guadalupe-fur-seal-status-review-2021.pdf?null> (accessed October 22, 2021).

Michel J., Bejarano A.C., Peterson C.H., Voss C. (Bureau of Ocean Energy Management). 2013. Review of Biological and Biophysical Impacts from Dredging and Handling of Offshore Sand. 261 pp. Available at <https://www.boem.gov/ESPIS/

5/5268.pdf> (accessed August 23, 2021).

NatureServe 2021. NatureServe Explorer [web application]. Search results for:

Enhydra lutris nereis, Southern Sea Otter. NatureServe, Arlington, Virginia. Available at <https://explorer.natureserve.org/> (accessed August 23, 2021).

Nightingale B., Simenstad C. 2001. Overwater Structures: Marine Issues. Prepared for Washington State Transportation Commission. Research Project T1803, Task 35, Overwater Whitepaper. May 2001. 181 p. Available at <https://www.wsdot.wa.gov/

research/reports/fullreports/508.1.pdf> (accessed August 23, 2021).

[NOAA] National Oceanic and Atmospheric Administration. 2021. How Oil Spills Affect Fish and Whales. Available at < https://response.restoration.noaa.gov/oil-and-chemical-spills/oil-spills/how-oil-spills-affect-fish-and-whales.html> (accessed October 25, 2021).

[NMFS] National Marine Fisheries Service. 1991. Final Recovery Plan for the Humpback Whale, Megaptera novaengliae. November 1991. 115 pp. Available at

<https://repository.library.noaa.gov/view/noaa/15993> (accessed October 21, 2021).

[NMFS] National Marine Fisheries Service. 2006. Biological Opinion for Continued Operation of the Diablo Canyon Nuclear Power Plant and San Onofre Nuclear Generating Station. September 18, 2006. 58 pp. ADAMS Accession No. ML063000348.

[NMFS] National Marine Fisheries Service. 2010. Final Recovery Plan for the Finback Whale (Balaenoptera physalus). July 2010. 121 pp. Available at

<https://repository.library.noaa.gov/view/noaa/4952> (accessed October 21, 2021).

[NMFS] National Marine Fisheries Service. 2016a. Letter from W.W. Stelle, Jr., NMFS, to R. Smith, U.S. Army Corps of Engineers, Los Angeles.

Subject:

Endangered Species Act Section 7(a)(2) Concurrence Letter for Installation of Exclusion Devices at the San Onofre Nuclear Generating Station. June 16, 2016. ADAMS Accession No. ML21299A252.

[NMFS] National Marine Fisheries Service. 2016b. Letter from K.B. Damon-Randall, NMFS, to J. Donaghue, NRC, regarding construction and operation of North Anna Power Station, Unit 3, in Louisa County, Virginia. November 3, 2016. ADAMS Accession No. ML16319A265.

[NMFS] National Marine Fisheries Service. 2017. Letter from R. Crabtree, NMFS, to J. Dixon-Herrity, NRC, and A. Dodd, Department of the Army, regarding Turkey Point Units 6 and 7 in Miami-Dade County, Florida. April 26, 2017. ADAMS Accession No. ML17143A153.

[NMFS] National Marine Fisheries Service. 2018. Letter from to E. Biondi, Federal Highway Administration, regarding the Federal Highway Administration Greater Atlantic Regional Fisheries Office 2018 Not Likely to Adversely Affect Program. April 30, 2018.

Available at <https://www.greateratlantic.fisheries.noaa.gov/protected/section7/

FHWA%20documents/fhwa_programmatic_esa_s7_consultation_april_2018.pdf>

(accessed August 23, 2021).

[NMFS] National Marine Fisheries Service. 2019. Gray Whale (Eschrichtius robustus):

Western North Pacific Stock. Revised March 15, 2019. 6 pp. Available at

<https://media.fisheries.noaa.gov/dam-migration/gray_whale_wnp_final_2018.pdf>

(accessed October 25, 2021).

[NMFS] National Marine Fisheries Service. 2020a. Recovery Plan for the Blue Whale (Balaenoptera musculus): First Revision to the July 1998 Recovery Plan for the Blue Whale. November 2020. 133 pp. Available at

<https://repository.library.noaa.gov/view/noaa/27399> (accessed October 21, 2021).

[NMFS] National Marine Fisheries Service. 2020b. Biological Opinion for Continued Operation of Oyster Creek Nuclear Generating Station Pursuant to a License Issued by the NRC in April 2009, Shutdown, and Ongoing Decommissioning. May 29, 2020.

53 pp. ADAMS Accession No. ML20153A226.

[NMFS] National Marine Fisheries Service. 2020c. Blue Whale (Balaenoptera musculus musculus): Eastern North Pacific Stock. Available at

<https://media.fisheries.noaa.gov/dam-migration/2019_sars_bluewhale_enp.pdf>

(accessed October 25, 2021).

[NMFS] National Marine Fisheries Service. 2020d. Fin Whale (Balaenoptera physalus velifera): California/Oregon/Washington Stock. Available at

<https://media.fisheries.noaa.gov/2021-08/2020-Pacific-SARS-Finwhale.pdf> (accessed October 25, 2021).

[NMFS] National Marine Fisheries Service. 2020e. Humpback Whale (Megaptera novaeangliae): California/Oregon/Washington Stock. Revised April 15, 2020. 10 pp.

Available at <https://media.fisheries.noaa.gov/dam-migration/2019_sars_humpback whale_cawaor.pdf> (accessed October 25, 2021).

[NMFS] National Marine Fisheries Service. 2021a. Guadalupe Fur Seal. Available at

<https://www.fisheries.noaa.gov/species/guadalupe-fur-seal> (accessed October 22, 2021).

[NMFS] National Marine Fisheries Service. 2021b. Blue Whale. Available at

<https://www.fisheries.noaa.gov/species/blue-whale> (accessed October 20, 2021).

[NMFS] National Marine Fisheries Service. 2021c. Fin Whale. Available at

<https://www.fisheries.noaa.gov/species/fin-whale> (accessed October 20, 2021).

[NMFS] National Marine Fisheries Service. 2021d. Humpback Whale. Available at

<https://www.fisheries.noaa.gov/species/humpback-whale> (accessed October 20, 2021).

[NMFS] National Marine Fisheries Service. 2021e. Gray Whale. Available at

<https://www.fisheries.noaa.gov/species/gray-whale> (accessed October 20, 2021).

[NMFS] National Marine Fisheries Service. 2021f. Loggerhead Turtle. Available at

<https://www.fisheries.noaa.gov/species/loggerhead-turtle> (accessed August 23, 2021).

[NMFS] National Marine Fisheries Service. 2021g. Green Turtle. Available at

<https://www.fisheries.noaa.gov/species/green-turtle> (accessed August 24, 2021).

[NMFS] National Marine Fisheries Service. 2021h. Leatherback Turtle. Available at

<https://www.fisheries.noaa.gov/species/leatherback-turtle> (accessed August 24, 2021).

[NMFS] National Marine Fisheries Service. 2021i. Olive Ridley Turtle. Available at

<https://www.fisheries.noaa.gov/species/olive-ridley-turtle> (accessed August 24, 2021).

[NMFS] National Marine Fisheries Service. 2021j. Section 7 Effect Analysis: Turbidity in the Greater Atlantic Region; Guidance for Action Agencies on How to Address Turbidity in Their Effects Analysis. Available at <https://www.fisheries.noaa.gov/new-england-mid-atlantic/consultations/section-7-effect-analysis-turbidity-greater-atlantic-region> (accessed October 25, 2021).

[NMFS and FWS] National Marine Fisheries Service and U.S. Fish and Wildlife Service.

1998a. Recovery Plan for U.S. Pacific Populations of the Loggerhead Turtle (Caretta caretta). January 12, 1998. 77 pp. Available at <https://ecos.fws.gov/docs/

recovery_plan/981201b.pdf> (accessed September 7, 2021).

[NMFS and FWS] National Marine Fisheries Service and U.S. Fish and Wildlife Service.

1998b. Recovery Plan for U.S. Pacific Population of the East Pacific Green Turtle (Chelonia mydas). January 12, 1998. 77 pp. Available at <https://ecos.fws.gov/docs/

recovery_plan/981201f.pdf> (accessed September 7, 2021).

[NMFS and FWS] National Marine Fisheries Service and U.S. Fish and Wildlife Service.

1998c. Recovery Plan for U.S. Pacific Population of the Leatherback Turtle (Dermochelys coriacea). January 12, 1998. 61 pp. Available at

<https://ecos.fws.gov/docs/recovery_plan/981201d.pdf> (accessed September 7, 2021).

[NMFS and FWS] National Marine Fisheries Service and U.S. Fish and Wildlife Service.

1998d. Recovery Plan for U.S. Pacific Population of the Olive Ridley Turtle (Lepidochelys olivacea). January 12, 1998. 63 pp. Available at <https://ecos.fws.gov/

docs/recovery_plan/981201a.pdf> (accessed September 7, 2021).

[ORR] Office of Response and Restoration, National Oceanic and Atmospheric Administration. 2020. How Do Oil Spills Affect Sea Turtles? Available at

<https://response.restoration.noaa.gov/about/media/how-do-oil-spills-affect-sea-turtles.html> (accessed August 23, 2021).

Rockwood RC, Elliott ML, Saenz B, Nur N, Jahncke J. 2020. Modeling Predator and Prey Hotspots: Management Implications of Baleen Whale Co-occurrence with Krill in Central California.

[SCE] Southern California Edison. 2016. SONGS Units 2 and 3 Updated Final Safety Analysis Report / Defueled Safety Analysis Report. Revision 3. November 2016. 2,972 pp. ADAMS Accession No. ML16357A263.

[SCE] Southern California Edison. 2020. San Onofre Nuclear Generating Station Units 2 and 3 Post-Shutdown Decommissioning Activities Report. Revision 1. May 2020.

31 pp. ADAMS Accession No. ML20136A339.

[SCE] Southern California Edison. 2021. Response to Request for Additional Information to Support Endangered Species Act Consultation. April 8, 2021. 11 pp.

ADAMS Accession No. ML21104A066.

[SDRWQCB] San Diego Region Water Quality Control Board. 2015. Waste Discharge Requirements for Southern California Edison Company, San Onofre Nuclear Generating Station, San Diego County, Discharge to the Pacific Ocean. Order No. R9-2015-0073.

NPDES No. CA0109282. December 15, 2015. Available at

<https://www.waterboards.ca.gov/sandiego/board_decisions/adopted_orders/2015/R9-2015-0073.pdf> (accessed October 6, 2021).

[SWRCB] State Water Resources Control Board. 2020. Water Quality Control Policy on the Use of Coastal and Estuarine Waters for Power Plant Cooling. As amended on September 1, 2020. Effective November 30, 2020. Available at

<https://www.waterboards.ca.gov/water_issues/programs/ocean/cwa316/policy.html>

(accessed October 6, 2021).

Suntsov A, Koslow JA, Watson W. 2012. The Spatial Structure of Coastal Ichthyoplankton Assemblages. California Cooperative Oceanic Fisheries Investigations Report 53:153-170. Available at <http://calcofi.org/publications/calcofireports/

v53/Vol_53_Suntsov_153-170.pdf> (accessed August 23, 2021).

[Tetra Tech] Tetra Tech, Inc. Californias Coastal Power Plants: Alternative Cooling System Analysis. Prepared for California Ocean Protection Council. February 2008.

749 pp. Available at <http://www.opc.ca.gov/webmaster/ftp/project_pages/

OTC/engineering%20study/CA_Power_Plant_Analysis_Complete.pdf> (accessed August 3, 2021).

Appendix A. Figures and Tables A-1

Figure A1. SONGS Site Layout A-2

Figure A2. SONGS Site Layout with Exclusion Area Boundary A-3

Table A1. Occurrences of Federally Listed Marine Species in the Action Area Likelihood of Occurrence in Action Species Common Name Status(a) Habitat Area(b)

Fish Inshore waters to 200 feet, primarily Unlikely. No suitable habitat present.

Acipenser medirostris green sturgeon, Southern DPS FT in the seawater and mixing zones of Species has never been impinged or bays and estuaries. entrained at facility.

Brackish coastal waters from Agua Unlikely. No suitable habitat present.

Hedionda Lagoon to the Smith Known to occur north of action area in FE, River mouth. Shallow lagoons and Eucyclogobius newberryi tidewater goby(c) San Onofre and San Mateo Creeks.

SSC lower stream reaches with slow, but Species has never been impinged or not stagnant, water and high entrained at facility.

oxygen levels.

Comprised of a suite of steelhead Unlikely. Species known to occur north populations that inhabit coastal of action area in San Mateo Creek, but California steelhead, South Oncorhynchus mykiss irideus FE stream networks from the Pajaro action area lacks suitable deep, open Central California DPS River south to, but not including, the ocean habitat. Species has never been Santa Maria River. impinged or entrained at facility.

Inhabits coastal stream networks California steelhead, Southern from the Santa Maria River system Oncorhynchus mykiss irideus FE Unlikely. (See above)

California DPS south to the U.S. border with Mexico.

A-4

Likelihood of Occurrence in Action Species Common Name Status(a) Habitat Area(b)

Mammals Occurs primarily in Baja California, Mexico, but occasionally found on FT, ST, Arctocephalus townsendii Guadalupe fur seal San Miguel and San Nicolas Unlikely. Suitable habitat absent.

FP Islands. Prefers rocky insular shorelines and sheltered coves.

Cosmopolitan distribution. Occurs in Unlikely. Suitable water depths absent subtropical, temperate, and in majority of action area. Regional subpolar waters around the world.

Balaenoptera borealis sei whale FE population density and habitat Usually observed in deeper waters preferences make likelihood of of oceanic areas far from the occurrence very low.

coastline.

In the eastern North Pacific Ocean, Low. Suitable water depths absent in ranges from the Gulf of Alaska majority of action area. However, south to Costa Rica. Winters off Balaenoptera musculus blue whale FE species is known to forage along the Mexico and Central America and southern California coast in summer and feeds during summer off the U. S.

fall months.

west coast.

One of the four stocks identified in U.S. waters occurs off the coasts of California, Oregon, and Balaenoptera physalus fin whale FE Low. (See above)

Washington. Migrates seasonally into and out of high-latitude feeding areas.

A-5

Likelihood of Occurrence in Action Species Common Name Status(a) Habitat Area(b)

Occurs from near Half Moon Bay south to Gaviota and San Nicolas Island. Typically occurs in coastal Unlikely. Action area is south of known Enhydra lutris nereis southern sea otter(c) FT, FP waters within 0.6 mi of shoreline inhabited range.

and often associated with kelp beds.

Prefers shallow waters while Low. Suitable water depths absent in feeding and calving but migrates majority of action area. However, through deep waters farther from species may be present in spring and fall gray whale, Western North shore. This population migrates Eschrichtius robustus FE during migration through California Pacific DPS from summer feeding grounds south coastal waters between its wintering along the coast of North America to breeding and calving grounds and wintering and calving areas off the summer feeding grounds.

coast of Baja California, Mexico.

A-6

Likelihood of Occurrence in Action Species Common Name Status(a) Habitat Area(b)

Prefers shallow waters while feeding and calving. Feeding grounds are in cold, productive coastal waters. This population Low. Suitable water depths absent.

breeds along the Pacific coast of humpback whale, Central However, individuals are occasionally Megaptera novaeangliae FE Central America, including off Costa American DPS observed in the Southern California Rica, Panama, Guatemala, El Bight.

Salvador, Honduras, and Nicaragua, and feeds off the west coast of the U.S. and southern British Columbia.

Prefers shallow waters while feeding and calving. Feeding grounds are in cold, productive coastal waters. This population breeds along the Pacific coast of Megaptera novaeangliae humpback whale, Mexico DPS FT Low. (See above)

Mexico and the Revillagigedo Islands, transits the Baja California Peninsula, and feeds across a broad range from California to the Aleutian Islands, Alaska.

Inhabits all oceans of the world. Unlikely. Suitable water depths absent.

Distribution is dependent on their Regional population density and habitat Physeter macrocephalus sperm whale FE food source and suitable conditions preferences make likelihood of for breeding. occurrence very low.

Mollusks A-7

Likelihood of Occurrence in Action Species Common Name Status(a) Habitat Area(b)

Inhabits rocky substrates in Unlikely. Suitable habitat absent.

intertidal and shallow subtidal reefs Surveys performed to support installation to about 18 feet deep. Typically of the large organism excluder devices Haliotis cracerodii black abalone FE occurs in habitats with complex on the offshore intake structures did not surfaces and deep crevices that detect any abalone species present in provide shelter for juveniles and the area.

adults.

Inhabits open rock or boulder Unlikely. Suitable water depths absent.

habitat interspersed with sand Surveys performed to support installation channels off the coast of California.

of the large organism excluder devices Haliotis sorenseni white abalone FE Most abundant at depths between on the offshore intake structures did not 80 and 100 feet, making it the detect any abalone species present in deepest-occurring abalone in the area.

California.

Reptiles A-8

Likelihood of Occurrence in Action Species Common Name Status(a) Habitat Area(b)

Circumglobal distribution throughout Moderate. No known nesting areas on the temperate and tropical regions southern California beaches. Low of the Atlantic, Pacific, and Indian potential for occurrence within action Oceans. Most abundant species of area due to generally low population sea turtle found in U.S. coastal densities. However, species has been waters. Have been reported as far observed in the past within the action Caretta caretta loggerhead sea turtle FT north as Alaska and as far south as area. Three individuals have been Chile. Most records along U.S. west captured or collected in the facility's coast are of juveniles off the forebays during the operational period California coast, with occasional (one live turtle in each of February 1993, sightings from Washington and July 1996, and July 2010). No incidental Oregon coasts. take has occurred since July 2010.

Globally distributed and generally Moderate. No known nesting areas on found in tropical and subtropical southern California beaches. Green waters along continental coasts and turtles have been consistently captured FE, islands. In the eastern North Pacific, or collected in the facility's forebays Chelonia mydas green sea turtle SSC species has been sighted from Baja during the operational period. In total, 42 California to southern Alaska, but it live and 2 dead turtles have been most commonly occurs from San collected. The last incidental take was in Diego south. May 2013.

A-9

Likelihood of Occurrence in Action Species Common Name Status(a) Habitat Area(b)

Moderate. No known nesting areas on southern California beaches. Low potential for occurrence within action Sighted with some regularity in area due to generally low population coastal waters off the west coast of densities. However, species has been the U.S. Sighting frequency is observed in the past within the action Dermochelys coriacea leatherback sea turtle FE greatest off central California.

area. Two individuals have been Nearly all sightings in southern captured or collected in the facility's California occur in deeper waters forebays during the operational period seaward of the Channel Islands.

(one live turtle in May 1994 and one dead turtle in May 1996). No incidental take has occurred since May 1996.

Moderate. No known nesting areas on southern California beaches. Low Globally distributed in tropical potential for occurrence within action waters. Occurs in the eastern area due to generally low population Pacific from southern California to densities. However, species has been Lepidochelys olivacea olive ridley sea turtle FT northern Chile. Infrequent observed in the past within the action occurrences documented off area. In June 2013, one dead individual southern, central, and northern was collected in the facility's forebays California. during the operational period. No incidental take has occurred since that time.

A-10

Likelihood of Occurrence in Action Species Common Name Status(a) Habitat Area(b)

(a)

Under the ESA, species may be designated as federally endangered (FE) or federally threatened (FT). Under California State statute, species may be designated as State-endangered (SE), State-threatened (ST), California species of special concern (SSC), State-rare (SR), or California Department of Fish and Wildlife fully protected (FP).

(b)

The potential to occur is based on the following criteria.

Present = Species observed during decommissioning project surveys or recently documented, and habitat conditions remain unchanged from the time of the record.

High = Species documented in vicinity of action area, suitable habitat present in the action area, but species not detected during decommissioning project surveys.

Moderate = Species either documented in vicinity of action area in past or historic surveys or scientific literature, or suitable habitat is found in action area within species known geographic range.

Low = No records of species in action area, habitat is marginal, or the species is conspicuous and was not detected during biological surveys.

Unlikely = No records of species in action area, and the action area lacks suitable habitat.

(c)

Species under the jurisdiction of the U.S. Fish and Wildlife Service.

Table Source: Adapted from CLSC 2019, Tables F1-2, F1-3, and F1-5 and supplemented with additional information from SCE 2020, SCE 2021, and NRCs incidental take records (see Table A2).

A-11

Table A2. All Sea Turtle Entrainment, 1984-Present Record of Incidental Date Species Condition Take 7/16/83 green alive ML051400365 1/11/84 green alive ML051400365 10/2/86 green alive ML051400365 9/23/88 green alive ML051400365 9/14/90 green alive ML051400365 9/26/90 green alive ML051400365 10/3/90 green dead ML051400365 10/30/90 green alive ML051400365 2/21/91 green alive ML051400365 3/14/91 green dead ML051400365 5/4/91 green alive ML051400365 10/6/91 green alive ML051400365 5/6/92 green alive ML051400365 6/3/92 green alive ML051400365 7/13/92 green alive ML051400365 7/30/92 green alive ML051400365 8/13/92 green alive ML051400365 9/9/92 green alive ML051400365 9/16/92 green alive ML051400365 2/27/93 loggerhead alive ML051400365 5/29/94 leatherback alive ML051400365 9/9/94 green alive ML051400365 5/8/96 green alive ML051400365 5/22/96 leatherback dead ML051400365 7/15/96 loggerhead alive ML051400365 11/24/97 green alive ML051400365 8/15/99 green alive ML051400365 6/19/00 green alive ML051400365 11/18/00 green alive ML051400365 8/15/02 green alive ML051400365 7/16/04 green alive ML051400365 9/13/04 green alive ML051400365 A-12

Record of Incidental Date Species Condition Take 3/15/05 green alive ML051400365 5/20/06 green alive ML072670143 6/7/06 green alive ML072670143 8/11/06 green alive ML072670143 9/4/07 green alive ML080430048 11/29/07 green alive ML080430048 10/10/09 green alive ML100350110 12/16/09 green alive ML100350110 7/12/10 loggerhead alive ML110410398 9/24/10 green alive ML110410398 9/30/10 green alive ML110410398 8/31/11 green alive ML12048A075 4/2/12 green alive ML12096A353 9/8/12 green alive ML13039A333 9/16/12 green alive ML13039A333 11/1/12 green alive ML13039A333 11/22/12 green alive ML13039A333 5/6/13 green alive ML14052A218 6/11/13 olive ridley dead ML14164A070 A-13