Southern California Edison's San Onofre Nuclear Generating Station Steam Generator Replacement Project

(Application No. A.04-02-026)

Welcome to the California Public Utilities Commission (CPUC) website for the replacement of steam generators for Units 2 and 3 at Southern California Edison's San Onofre Nuclear Generating Station (SONGS). An application for this project was submitted to the CPUC on February 27, 2004. The Project was reviewed under the California Environmental Quality Act (CEQA). A Final Environmental Impact Report (EIR) was issued in September 2005 and the CPUC approved the project in December 2005. This site provides access to public documents and information relevant to the CEQA review process and project implementation.


Southern California Edison Company (SCE) filed an application with the CPUC to: (1) replace the San Onofre Nuclear Generating Station Units 2 and 3 (SONGS 2 & 3) steam generators; (2) establish ratemaking for cost recovery; and (3) address other related steam generator replacement issues. The project will enable SONGS 2 & 3 to remain in service until the end of the current terms of the Nuclear Regulatory Commission (NRC) licenses. The current licenses both authorize SONGS 2 & 3 to operate until 2022. However, the existing steam generators have exhibited degradation and they are currently predicted to reach the end of their operating life within the next several years. The original steam generators will eventually reach a state where, under applicable NRC regulations, either the steam generators must be replaced or the units must be shut down.

SONGS 2 & 3 went into operation in 1983 and 1984, respectively. SONGS 2 & 3 use four steam generators, two per unit, which are large heat exchangers that convert heat from the reactor into steam to drive the turbine generators and produce electricity. All four will be replaced as part of the project. SONGS 2 & 3 produce a combined nominal 2,150 net megawatts of electric power, enough to power approximately 2.1 million homes. The SONGS facility is located in northwest San Diego County and surrounded by Camp Pendleton, San Onofre State Beach, and Interstate 5.

Environmental Review Process

SCE filed a PEA with the Application in February 2004. This document provided a starting point for the environmental review process conducted by the CPUC.

The CPUC on October 1, 2004, issued a Notice of Preparation of an Environmental Impact Report (EIR) for SONGS Steam Generator Replacement Project. Scoping meetings were held in October 2004. Scoping meetings were held in October 2004.

The Draft Environmental Impact Report (DEIR) was issued on April 15, 2005.

The submittal period for written comments on the Draft EIR ended May 31, 2005.

The Final Environmental Impact Report (Final EIR) was issued on September 21, 2005. The Final EIR consists of two volumes: Volume I is the complete EIR showing changes made to the Draft EIR, and Volume II consists of all comments on the Draft EIR and responses to comments.

The CPUC found the Final EIR to be adequate and certified the document as compliant with CEQA. The CPUC issued its decision D.05-12-040 on December 15, 2005.

Project Activities Subsequent to CPUC Approval

In December 2008, CPUC issued authorization to SCE to begin the steam generation replacement process which includes the following steps:

  • Replacement steam generator transport
  • Replacement steam generator staging and preparation
  • Original steam generator removal, staging and disposal
  • Replacement steam generator installation and return to service

Compliance review for pre-construction mitigation measures identified in the Mitigation Monitoring Plan as presented in the Final EIR has been conducted by CPUC. This plan ensures that the approved project will be conducted as defined, and that all adopted mitigation measures and Applicant Proposed Measures will be implemented in order that effects on the environment do not exceed those described in the Final EIR. A CPUC Notice to Proceed was issued after compliance with pre-construction mitigation requirements was satisfied by SCE. A CPUC Environmental Monitor monitored the steam generator replacement activities to ensure that they are conducted in accordance with the approved mitigation measures and permit conditions. Reports documenting this monitoring activity are available here.

For Additional Information

Requests for additional information should be sent to:

Jensen Uchida, CPUC Project Manager
c/o Aspen Environmental Group
235 Montgomery Street, Suite 935
San Francisco, CA 94104

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