Centralized Dry Storage of Nuclear Fuel: Lessons for U.S. Policy from Industry Experience and Fukushima

The Fukushima nuclear event of March 2011 dramatically revealed the potential risks of holding significant spent nuclear fuel at wet pools requiring continuous water circulation to maintain safe cooling. The housings for four spent fuel pools were badly damaged, and all pools lost cooling and nearly suffered fuel exposure. These conditions had the potential to result in catastrophic radiation release, rivaling or exceeding safety concerns over the nuclear reactors themselves. In contrast, the nine casks of spent fuel in dry storage at the Fukushima site hit by the same earthquake and tsunami experienced no material damage and posed no safety concerns.
It is unlikely that any U.S. reactors face a comparable environmental threat, but due to the inability to implement a timely spent fuel disposal program at Yucca Mountain, all of the commercial nuclear plants in the U.S. have spent fuel pools that are filled with roughly five reactor cores of spent fuel, and most have also had to build on-site dry storage facilities (Independent Spent Fuel Storage Installations or ISFSIs) for handling fuel discharges in excess of pool capacities.
A better means of handling this spent fuel, with regard to both costs and safety, would be for the federal government to restart a spent fuel handling program at one or a few centralized, interim dry storage facilities. This idea was recently endorsed in a January 2012 report by the Blue Ribbon Commission on America’s Nuclear Future, but no studies to date have assessed what size and pace of program might address today’s needs.
This paper presents several assessments of how a new program could be designed to address alternative priorities for improved spent fuel handling, including priority for shut-down plants, avoiding new at-reactor storage site developments, returning existing ISFSIs, and “de-densification” of fuel in wet pools. We find that a program beginning in 2020 with a removal capacity of 6,000 metric tons of uranium (MTU) per year for 10 years and a 3,000 MTU per year pace thereafter would be able to accommodate all of these goals — allowing full decommissioning of sites awaiting fuel removal, retiring all private ISFSIs by 2030, and achieving approximately a 10% reduction in average wet pool density. By contrast, delaying a new federal program by 10 years would cost the industry about $1.6 billion in increased at-reactor storage costs and represent a failure to respond in a timely fashion to some of the important lessons from Fukushima.