The California Public Utilities Commission (CPUC) has a great opportunity in its oversight of Diablo Canyon's closure. PG&E is plagued by the reality of having to store 2,000 tons of highly radioactive nuclear waste on an earthquake fault-ridden coastline into the foreseeable future. Currently, the waste in the dry cask storage is sealed in half-inch thick stainless steel canisters inside concrete overpacking affixed to huge concrete slabs, easily visible from the air and from the sea.
The CPUC can give PG&E its marching orders: Pack the waste in the type of robust containers that are used in Europe and Japan, and create a model for hardened on-site storage, better known as HOSS. In HOSS, dry casks are bermed and shielded from visual detection. They are distributed out over a large area so that they are not as vulnerable to terrorism or acts of malice. They are safer.
At Fukushima, the only part of the nuclear plants that were not destroyed by the earthquake and tsunami were the dry canisters. They were made of 9-inch thick steel. The CPUC can order PG&E to find a vendor to supply similar canisters for the waste at Diablo Canyon. They can also order PG&E to build the country's first HOSS site for waste storage. If PG&E complies with those orders, then they can recoup the costs from the ratepayers. If not, they must bear the cost alone.
The CPUC can protect the population in a responsible, thoughtful way. There is no solution to the highly radioactive spent fuel problem—nowhere for it to go—so it's much more logical to plan for its relatively safe storage on-site.