Windscale

Sellafield Ltd
Aerial view of the site
Location of Sellafield Ltd in Cumbria
Country	United Kingdom
Location	Seascale, Cumbria
Coordinates	54°25′14″N 3°29′51″W / 54.4205°N 3.4975°W / 54.4205; -3.4975Coordinates: 54°25′14″N 3°29′51″W / 54.4205°N 3.4975°W / 54.4205; -3.4975
Commission date	1956
Owner(s)	NDA
Operator(s)	Sellafield Ltd
Nuclear power station
Reactor type	Magnox, AGR prototype
Thermal power station
Primary fuel	Nuclear
Power generation
Units decommissioned	4 x 50 MWe, 1 x 24 MWe (net) 4 x 60 MWe, 1 x 36 MWe (gross)
grid reference NY034036

Sellafield is a nuclear fuel reprocessing and nuclear decommissioning site, close to the village of Seascale on the coast of the Irish Sea in Cumbria, England. The site is served by Sellafield railway station. Sellafield incorporates the original nuclear reactor site at Windscale, which is currently undergoing decommissioning and dismantling, and Calder Hall, a neighbour of Windscale, which is also undergoing decommissioning and dismantling of its four nuclear power generating reactors. It is the site of the world's first commercial nuclear power station to generate electricity on an industrial scale.

Sellafield was previously owned and operated by the United Kingdom Atomic Energy Authority (UKAEA) and then, following the division of UKAEA in 1971, it was British Nuclear Fuels Ltd. Since 1 April 2005, it has been owned by the Nuclear Decommissioning Authority (NDA) and is now operated by Sellafield Ltd.

In 2008, the NDA awarded Nuclear Management Partners (NMP) the position of Parent Body Organisation of Sellafield Ltd. under their standard management model for NDA sites. This consortium, composed of US company URS, British company AMEC, and AREVA of France, was initially awarded a contract for five years, with extension options to 17 years.

On 13 January 2015, the NDA announced that NMP would lose the management contract for Sellafield Ltd. as the "complexity and technical uncertainties presented significantly greater challenges than other NDA sites", and the site was therefore "less well suited" to the NDA's existing standard management model. The new structure, which came into effect on 1 April 2016, saw Sellafield Ltd. become a subsidiary of the NDA.