General description and operational experience of a dry storage facility for JRR-3 spent fuels in JAERI

Kusunoki, Tsuyoshi ; Koda, Nobuyuki ; Uchiyama, Junzo*

A dry storage facility (DSF) was constructed in March 1982 to store the JRR-3 metallic natural uranium spent fuel elements those had been stayed under water in a core or a spent fuel pool for a long period (Maximum : about 20 years). The facility consists of a storage, an air circulation system, an auxiliary system and a control room. The storage is composed of the concrete shielding and 100 dry-wells. In each dry-well, a stainless steel made canister with the spent fuels is stored. The air circulation system has an air-inlet and outlet pipes, headers and air circulation blowers to circulate air in the system and maintain the pressure inside the dry-well below the atmosphere. This system also performs the role as radiation monitoring system. The facility is designed to satisfy safety requirements as a nuclear fuel facility, such as criticality safety, radiation shielding and earthquake performance. JAERI has successfully experienced the dry storage of 1798 spent fuel elements about for 20 years.