Sellafield is the U.K.’s primary nuclear-fuel reprocessing facility. It covers a 700-acre site, employs 11,000 workers and is located 70 miles north of Liverpool on the Irish Sea. Sellafield contains the Calder Hall nuclear power station (containing four Magnox reactors), the world’s first commercial nuclear powerplant, which went online in 1956 and closed in 2003. Calder Hall also produced plutonium for weapons purposes until 1995. Its four cooling towers were demolished by controlled explosions in September 2007. (ENR 10/8/07 p. 15)

Sellafield also contains the Windscale Piles, two air-cooled, graphite-moderated reactors that constituted Britain’s first weapons-grade plutonium production facility, which went online in 1950. The piles were shut down following a fire in 1957, which destroyed Pile One. Decommissioning of the piles began in the 1990s.

The site also contains the Windscale Advanced Gas-Cooled Reactor, which was shut down in 1981 and is now being decommissioned. A fourth major facility is the Magnox reprocessing plant, which, since 1964, has reprocessed spent fuel using the “plutonium uranium extraction” (Purex) method.

A fifth facility is the Thermal Oxide Reprocessing Plant (Thorp), which, since 1994, has been reprocessing irradiated-oxide nuclear fuel from both U.K. and foreign reactors. It chemically separates the uranium, plutonium and waste products. In 2005, it was discovered that 83,000 liters of radioactive waste had leaked from a cracked pipe at Thorp.

A sixth facility, the Windscale Vitrification Plant, has been sealing high-level radioactive waste in glass since 1991. The high-level liquid waste is evaporated and converted to a powder in a melter. The powder (calcine) is mixed with molten glass and poured into stainless-steel containers and stored on-site.

A seventh major facility, the Sellafield MOX Plant, has been separating plutonium from spent fuel and recycling it into mixed oxide fuel since 1997.

Nuclear Management Partners Ltd., a consortium made up of Amec, URS and Areva, was awarded a contract in 2008 to operate, clean up and decommission Sellafield. NMP owns and manages Sellafield Ltd., which comprises the Sellafield complex as well as the Capenhurst plant in Cheshire. Under the current five-year contract, Sellafield Ltd.’s annual site-funding limit, set by the Nuclear Decommissioning Authority (NDA), is $2.27 billion, with a further 12-year option. The workforce decommissioning facilities at Sellafield currently numbers 2,230.

Over the course of the next century, the NDA hopes to decommission the plants and facilities at Sellafield, with the higher-hazard legacy ponds and silos as the top priority. By 2120, the NDA expects the site will have achieved brownfield status, with all the waste disposed, and reusable products stored on-site, pending any decisions on further use. (ENR 4/24/06 p. 17; 7/21/08 p. 14)

Location: Britain

Estimated Cost: $30 billion

Construction Period: 2006-2120

Owner: Nuclear Decommissioning Authority

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