Managing Aging Effects on Used Fuel Dry Cask for Very Long-Term Storage

Abstract

The cancellation of the Yucca Mountain repository program in the Unites States raises the prospect of very long-term storage (i.e., >120 years) and deferred transportation of used fuel at the nuclear power plant sites. While long-term storage of used nuclear fuel in dry cask storage systems (DCSSs) at Independent Spent Fuel Storage Installations (ISFSIs) is already a standard practice among U.S. utilities, recent rule-making activities of the U.S. Nuclear Regulatory Commission (NRC) indicated additional flexibility for the NRC licensees of ISFSIs and certificate holders of the DCSSs to request initial and renewal terms for up to 40 years. The proposed rule also adds a requirement that renewal applicants must provide descriptions of aging management programs (AMPs) and time-limited aging analyses (TLAAs) to ensure that the structures, systems, and components (SSCs) that are important to safety in the DCSSs will perform as designed under the extended license terms. This paper examines issues related to managing aging effects on DCSSs for very long-term storage (VLTS) of used fuels, capitalizing on the extensive knowledge and experience accumulated from the work on aging research and life cycle management at Argonne National Laboratory (ANL) over the last 30 years. The technical basis for acceptable AMPs and TLAAs is described, as are generic AMPs and TLAAs that are being developed by Argonne under the support of the U.S. Department of Energy (DOE) Used Fuel Disposition Campaign for R&D on extended long-term storage and transportation.

Advanced Surveillance Technologies for Used Fuel Long-Term Storage and Transportation

“…High-burnup fuel issues [15] and managing aging effects on used fuel dry cask systems [16] for extended long-term storage and transportation are two other areas where Argonne is participating in the DOE Used Fuel Disposition Campaign for R&D on storage and transportation. Two generic aging management programs are being developed: one for welded canister seal and leakage monitoring and the other for bolted cask seal and leakage monitoring.…”

Evaluation of diffusion parameters and phase formation between tungsten films and glassy carbon

“…This waste is then stored in dry cask storage containers which are meant to be temporary until they are transferred to permanent geological sites. Demand for dry casks with longer service lifespan beyond 60 years [2] is expected to be on the increase in the near future due to dearth of permanent repositories. Currently, dry cask storage devices are made from materials such as stainless steel, cast iron and concrete.…”

“…These materials have a remarkable range of mechanical, electronic, and electrochemical properties and many possible applications. The ability of carbon to exhibit diverse properties originates from the flexibility to form sp 1 , sp 2 , and sp 3 -hybridized bonds [7]. Glassy carbon is a synthetic form of carbon formed by pyrolysis of organic resins at elevated temperatures [8,9].…”