Coastal Mitigation Linked to the Effects of the SONGS Cooling Water System (San Onofre Nuclear Generating Station = SONGS) Unit 3 diffuser Unit 2 diffuser San Onofre kelp forest Unit 3 intake Unit 2 intake SONGS Intakes cause substantial reduction in nearshore fish Discharge causes substantial reduction in San Onofre kelp forest

Losses of immature fish in the cooling water intake system is projected to cause substantial reductions in populations of adult fish in the S. California Bight In-plant losses of juvenile and adult fish led to reductions in the local abundance of mid-water fish populations in near vicinity of SONGS The discharge plume caused a substantial reduction in size of the kelp forest community at San Onofre that resulted in losses of kelp, fish, & invertebrates Adverse Effects Attributed to SONGS Cooling Water System Include:

Condition A: Wetland Mitigation Out-of-kind mitigation to compensate for in-plant losses of immature fish. Condition B: Behavioral Barriers Mitigation In-kind mitigation to reduce in-plant losses of juvenile & adult fish. Condition C: Kelp Reef Mitigation In-kind mitigation to compensate for losses of kelp and kelp bed fish and invertebrates. Condition D: Administrative Structure Provides for scientific oversight and monitoring of mitigation projects that is independent of SCE. Mitigation required by the CCC for the impacts caused by SONGS cooling water system includes four conditions:

Condition A: Wetland Mitigation San Dieguito Lagoon before excavation and grading (2003) old airfield/ruderal upland old agricultural fields ruderal upland Del Mar Racetrack San Dieguito River Freeway ruderal agricultural fields

intertidal habitat Condition A: Wetland Mitigation San Dieguito Lagoon after excavation and grading (2010) salt marsh subtidal basin nesting sites Del Mar Racetrack San Dieguito River I-5 Freeway salt marsh nesting site disposal site salt marsh mud flats

Restored wetland now providing habitat for invertebrates, fish, birds & eel grass

Salt Marsh Vegetation Monitoring & Adaptive Management Salt marsh vegetation is underperforming in some areas. Monitoring has identified elevation and tidal inundation as the cause of sparse vegetation. SCE is planning to re-grade these areas in the coming year to correct the problem. March 2013 bare

Condition C: Kelp Reef Mitigation Artificial Reef (mitigation site) SONGS San Clemente Oceanside San Mateo (reference site) Barn (reference site) N 5 km Wheeler North Reef constructed in two phases: Phase1 - 9 hectares (completed October 1999) Phase hectares (completed September 2008) Phase 1 + Phase 2 = 71 hectare artificial reef

Giant kelp Dense surface canopy of giant kelp present on Wheeler North Reef within 2 years of construction Summer 2010 Image from Landsat 5 May 30, 2010 Wheeler North San Mateo San Onofre SONGS

Wheeler North Reef supports populations of algae, invertebrates and fish that are similar to natural reference reefs

Slide11 Standing stock of kelp bed fish is less than the required 28 tons Data analysis and discussions with SCE are ongoing to determine the best method for addressing the short fall in fish biomass

Importance of monitoring Data from independent monitoring are used to determine: 1.whether mitigation is done according to approved plans 2.whether the performance standards are met 3.the causes for any failures to meet the performance standards 4.the most appropriate methods for remediation

1.Provides information that helps guide future restoration efforts 2.Develops and refines sampling approaches 3.Contributes to an in-depth understanding of the natural history and ecology of wetland and kelp forest systems Broader benefits of monitoring

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