PG&E 2015 Triennial Review of
Nuclear Decommissioning Trusts and Costs




Every 3 years the CPUC reviews the investor owned utilities' proposed costs required for decommissioning California’s nuclear power plants. 

On March 1, 2016, PG&E filed its Application for its Nuclear Decommissioning Cost Triennial proceeding, seeking CPUC approval for:      

Diablo Canyon Trusts

  • $117.3 million annual revenue requirement ($0 authorized in 2012 Triennial Review)
  • Increase Diablo Canyon decommissioning cost estimate by $1.3 billion to an updated total of $3.78 billion    

Humboldt Bay Operating Costs & Trusts

  • $62.9 million annual revenue requirement (reduced from $96.3 million approved in the 2012 Triennial Review) 
  • Annual operating costs of about $4.5 million 
  • Estimated $531.3 million to complete the remaining decommissioning work (as of Dec 2014)   
  • PG&E estimates that the total cost to complete Humboldt Bay decommissioning is now $1.055 billion, an increase of $77.1 million over the 2012 authorized estimate of $977.9 Million  


On July 15, 2016, the CPUC issued a Ruling setting the Scope of the proceeding to included, among other things, the reasonableness of PG&E’s proposed costs. The CPUC subsequently issued a Ruling with a revised proceeding schedule.    


PG&E will issue Rebuttal Testimony to parties on September 12, 2016. 


Evidentiary Hearings are scheduled at the CPUC for September 19 - 23, 2016.



Public Advocates Office (the Office) Position

The Office made an in-depth review of PG&E’s application regarding Humboldt Bay #3 and Diablo Canyon power plants and finds that the most recent decommissioning trust fund balances should be used when calculating ratepayer contributions to the trust funds. Public Advocates Office recommends $175.3 million in revenue requirements for Humboldt Bay and Diablo Canyon, as opposed the PG&E’s request of $184.7 million.


  • Humboldt Bay #3:  does not oppose PG&E’s updated decommissioning cost estimate, 2017-2019 O&M forecasts, 2013-2015 O&M reasonableness or the reasonableness of completed decommissioning projects. 
  • Diablo Canyon: The estimated overall contingency for the decommissioning cost estimate should be reduced from 25% to 17.4%. Additional funding for breakwater disposition based on PG&E’s new assumptions should not be approved at this time.

Public Advocates Office continues to be interested in the timing of the U.S. Department of Energy’s spent nuclear fuel acceptance.  

Public Advocates Office asserts evidentiary hearings are necessary in order for the CPUC to make a full review of PG&E’s proposal.    


See Public Advocates Office’s: 

April 25, 2016 Testimony providing it detailed analysis of PG&E's Application.  

April 4, 2016 Protest to PG&E’s Application.



CPUC Docket

See the Proceeding docket.

Here you can find a full record of the case, as well as subscribe to proceeding updates. 



Other Resources

CPUC’s Nuclear Decommissioning Webpage  

U.S. Nuclear Regulatory Commission’s Diablo Canyon Unit 1 Webpage  

U.S. Nuclear Regulatory Commission’s Diablo Canyon Unit 2 Webpage