Account and Control of Nuclear Materials at the WWR-SM Reactor in the Institute of Nuclear Physics, Tashkent

The WWR-SM research reactor has been in operation since 1959, with a variety of fuels-10 %-enrichment Ek-10, 90 %-enrichment IRT-3M (1972), 36 %-enrichment IRT-3M (1998). The move today is toward use of IRT-4M fuel with < 20 % enrichment. Tight control of nuclear materials has been maintained over the years by physical and administrative means: fresh fuel is stored in a dry locked room, while spent fuel is kept in racks in three fuel storage pools (FSPs) containing high-purity water that minimizes cladding corrosion. Between 1991 and 1994 the accounting and control of nuclear materials was according to the method used by Ministry of Atomic Energy and Industry (MINATOM) in Russia. Since 1994, nuclear materials data are forwarded to the International Atomic Energy Agency (IAEA) and are checked by quarterly inspections. An agreement was signed with Russia in 1997 for supply of fresh fuel and take back of spent fuel for reprocessing (with return of fission-product waste to Uzbekistan).