July 10, 2013

Safety Aspects of Wet Storage of Spent Nuclear Fuel

The Department of Energy (Department) is responsible for managing and storing spent nuclear fuel (SNF) generated by weapons and research programs and recovered through nonproliferation programs.  The SNF consists of irradiated reactor fuel and cut up assemblies containing uranium, thorium and/or plutonium.  The Department stores 34 metric tons of heavy metal SNF primarily in two wet storage basins located at the Savannah River Site and the Idaho National Laboratory.

Wet storage requires operational vigilance and reliance on mechanical systems to ensure the safety of workers, the public and the environment.  The risk associated with long-term wet storage of SNF is well-demonstrated by the recent disaster in Japan.  While not subject to damage from tsunamis, environmental or mechanical issues are within the realm of possible damage scenarios faced by the Department’s SNF storage facilities. 

Because it lacks a clear disposition path, the Department had not developed definitive plans to dispose of its SNF.  In Fiscal Year 2010, the Department withdrew its intent to develop a geological repository at Yucca Mountain, Nevada to dispose of SNF and high-level waste.  Then in 2011, the Department deferred processing aluminum-clad SNF, some of which is in wet storage, until recommendations of the Blue Ribbon Commission on America’s Nuclear Future were issued and evaluated.  As a consequence, the Department determined it must maintain interim SNF wet storage facilities longer than planned and until disposition options become available. 

Given the lack of disposition paths, the Department is taking steps to manage the safety of its SNF wet storage basins, namely L-Basin and CPP-666.  Our review revealed that, as required by both Federal and Department regulations, program officials had analyzed the risks related to storage, documented these analyses, and concluded that the continued use of the wet storage facilities was appropriate.  While the Savannah River Site has initiated activities designed to support the prolonged storage of SNF in L-Basin, completion of these activities is being deferred due to funding constraints. 

TOPIC: Environmental Cleanup