Diablo Canyon panel calls for accelerated decommissioning

11 January 2019

A panel set up as a forum to provide community input into matters related to the decommissioning of the Diablo Canyon nuclear power plant has recommended that the two-unit plant be decommissioned within ten years of its 2025 shutdown.

Diablo Canyon (Image: US Nuclear Regulatory Commission/PG&E)

The Diablo Canyon Decommissioning Engagement Panel (DCDEP) makes the recommendation in a newly issued 2018 Strategic Vision, in which it says the decommissioning of the two-unit plant should begin immediately upon its shutdown, which is due to take place in 2025.

The report recommends that a so-called 'DECON' option - where work begins to decontaminate the site immediately after fuel is removed from the reactor - is chosen rather than the 'SAFSTOR' option, in which the defuelled plant is kept intact and placed in protective storage for an extended period of time to allow radioactivity levels to decay before dismantlement begins. The SAFSTOR route can take up to 60 years to complete.

Pacific Gas and Electric Company (PG&E) in August 2016 announced plans to retire Diablo Canyon's two pressurised water reactors - the only remaining nuclear generating capacity in California - at the end of its current operating licences, which expire in 2024 for unit 1 and 2025 for unit 2. The DCDEP was subsequently convened by the company as a volunteer, non-regulatory body to foster and encourage open communication, public involvement and education on decommissioning plans and activities.

The Strategic Vision has been prepared by the DCDEP as a 'living document' that will be amended and refined as the decommissioning process continues. Its recommendations are based on the views of the community as expressed during public meetings and workshops, as well as through emails, letters and other correspondence.

"The decommissioning (decontamination) process should begin immediately upon shutdown with a goal of 10 years for completion of radiological decommissioning and decontamination, avoiding SAFSTOR (which allows up to 60-year delay in decontamination)," the report recommends. It also recommends that the health and safety of the community and the environmental quality of the area "should be the primary consideration when evaluating cost-effective methods of decommissioning in order to save ratepayers money".

The areas surrounding the plant are a "spectacular natural resource" that needs to be conserved "in perpetuity" while allowing for managed public access and use, the report notes. It also calls for an exploration of "repurposing" facilities as a way to both reduce the amount of demolition materials created and create opportunities for new local jobs and economic development, including the retention of marine facilities such as breakwaters and the associated harbour.

Over the coming year the DCDEP has scheduled workshops and meetings on spent fuel storage, engagement panel evaluation, potential economic impacts and economic development opportunities, and transportation. Vision, Goals and Recommendations covering these topics will be included in the 2019 edition of the Strategic Vision.

Researched and written by World Nuclear News