Southern California Edison has awarded Holtec an EPC contract to build an underground used-fuel storage facility for the retired San Onofre Nuclear Generating Station in California.
Under the contract, Holtec will also perform pool-to-pad loading services for all used fuel and non-fuel waste stored in the spent fuel pools of SONGS 2&3.
The HI-STORM UMAX underground facility will have the capacity for 2669 used-fuel assemblies in MPC-37 multi-purpose canisters, each containing 37 used fuel assemblies.
The most corrosion resistant grade of stainless steel, 316L grade austenitic stainless steel, will be used for the confinement boundary of the MPC in order to ensure a long service life in the site’s salt air environment, says Holtec. All external surfaces of the storage cavity that are in contact with the ambient air will also be upgraded from carbon steel to stainless steel to minimise in-service maintenance requirements.
Holtec also noted that the HI-STORM UMAX facility has been fortified to withstand ‘any conceivable threats to its integrity,’ including earthquakes, tsunamis, aircraft impact, a severe fire and a long-lasting massive flood.
Another HI-STORM UMAX ISFSI, at the Callaway Nuclear Plant in Missouri, is under construction under a turnkey contract between Ameren and Holtec. The project, which will be the first of its type, is scheduled to be commissioned in 2015.
Photo: San Onofre Nuclear Generating Station at sunset (Source: SCE)