Edison and SDG&E 2012 Triennial Review of
Nuclear Decommissioning Trust and Costs



Every 3 years the CPUC reviews the investor owned utilities proposed costs required for decommissioning California’s nuclear power plants. Edison and SDG&E are co-owners of the San Onofre Nuclear Generating Station.  

On April 5, 2013, Edison and SDG&E filed with the CPUC their amended  Application for their Triennial review of Nuclear Decommissioning Trust and Costs, requesting approval of:  

Edison and SDG&E for SONGS:

  • SONGS 1: $14.9 million for Phase 2 decommissioning work completed between January 1, 2009 and December 31, 2012 as well as an estimated $182.3 million for the remaining decommissioning work
    • SDG&E estimated its share of the costs =  $36.5 million 
  • SONGS 2 and 3:    
    • $4.1 billion in total decommissioning costs  
    • $39.7 million increased contributions to the Trust Funds as part of the Nuclear Decommissioning Cost Charge effective January 1, 2014 
    • To stay the SONGS 2 3 proceeding, pending the completion of a site-specific Decommissioning Plan  
    •  SDG&E estimated its share of the costs:
      • SONGS 2 = $400.6 million
      • SONGS 3 = $423.1 million. SDG&E’s rate recovery for annual contribution to the Decommissioning Trust for SONGS 1, 2, and 3 in the totals $16.4 million, effective January 1, 2014  

 Edison for Palo Verde: 

  • $513.5 million in decommissioning costs 


Final CPUC Decision

On December 18, 2014, the CPUC issued its Final Decision on the Triennial review approving Decommissioning cost estimates for Edison and SDG&E. 

  • SONGS Unit 1 = $182 million
  • SONGS Unit 2 & SONGS 3 = $4.1 billion
  • Palo Verde = $513 million



Public Advocates Office (the Office) Position 

The Office evaluated Edison’s  and SDG&E's requests for reasonableness and prudence of the proposed costs  required to decommission its nuclear power plants. 

SONGS 1: The Office agreed with the utility’s proposal that no further ratepayer contribution needed.  The Office did not contest the $182.3 million for the remaining costs, which includes a 25% contingency factor.  However, the Office was unable to confirm the reasonableness of the proposed $14.9 million for work completed between 2009-2012 given that Edison was unable to provide the appropriate historical records.  The Office recommended the disposition of the $109 million forecast over-contribution should be addressed in the next triennial review. 

  • The Office did not oppose SDG&E’s $36.5 million estimated share of contribution. 

SONGS 2 & 3: The Office supported Edison’s request to stay a portion of this proceeding in order to develop an accurate estimate of the decommissioning costs, which operated until January 2012. The Office agreed that the current annual contribution for SONGS 2 and 3 of approximately $23 million should be retained. However, the Office recommended that the CPUC should deny approval of Edison's proposed cost estimates consistent with their stay request, until a site-specific decommissioning engineering and contingency study is completed. The Office supported SDG&E’s current decommissioning contribution without changes at approximately $8 million annually.   

  • $4.1 billion decommissioning 
  •  $39-42 million increase request for 2014 decommissioning contribution

Accordingly, the Office recommended the CPUC should require the utilities to separately track accounting of contingency, overages, and contractor costs for greater transparency, accountability, and future forecasting studies.  A permanent nuclear decommissioning data retention system should be required to store and track costs over the project duration. 


Palo Verde:  The Office agreed with Edison’s proposal that no further ratepayer contribution is required. The Office recommended that the CPUC should apply 13.79% to 19.98% unadjusted contingency factors to all decommissioning costs as calculated by the Palo Verde TLG Study and authorized by the Arizona Public Service, the regulator for the majority of the plant’s ownership.  The CPUC should reduce Edison’s cost estimate of $513 million by $26.1 million.   


See the Office’s: 

September 20, 2013 Testimony. 



Proceeding Status 

See the Proceeding docket.  




Other Resources

NRC Webpage for SONGS Unit 1 Decommissioning  

NRC Webpage for SONGS Units 2 & 3 Decommissioning