Sellafield is a nuclear processing and former electricity generating site, close to the village of Seascale on the coast of the Irish Sea in Cumbria, England. Sellafield was previously owned and operated by British Nuclear Fuels plc (BNFL), but is now operated by Sellafield Ltd and, since 1 April 2005, has been owned by the Nuclear Decommissioning Authority.
Facilities at the site include the Thorp nuclear fuel reprocessing plant and the Magnox nuclear fuel reprocessing plant. It is also the site of the remains of Calder Hall Magnox nuclear power station — the world's first commercial nuclear power station, which is now being decommissioned, as well as some other older nuclear facilities. In 1981 the site was re-named from Windscale to Sellafield in a bid by the United Kingdom Atomic Energy Authority to change the public profile of nuclear energy.
The site is served by Sellafield railway station.
The Sellafield site was originally occupied by ROF Sellafield, a Second World War Royal Ordnance Factory, which, with its sister factory, ROF Drigg, at Drigg, produced TNT. After the war, the Ministry of Supply adapted the site to produce nuclear weapons materials, principally plutonium and construction of the nuclear facilities commenced in 1947. The site was renamed Windscale to avoid confusion with the Springfields uranium processing factory near Preston. The two air-cooled, graphite-moderated Windscale reactors constituted the first British weapons grade plutonium-239 production facility, built for the British nuclear weapons programme of the late 1940s and the 1950s. Windscale was also the site of the prototype British Advanced gas-cooled reactor.
With the creation of the United Kingdom Atomic Energy Authority (UKAEA) in 1954, ownership of Windscale Works passed to the Authority. The first of four Magnox reactors became operational in 1956 at Calder Hall, adjacent to Windscale, and the site became Windscale and Calder Works. Following the breakup of the UKAEA into a research division (UKAEA) and a production division, British Nuclear Fuels Ltd (BNFL) in 1971, the major part of the site was transferred to BNFL. In 1981 BNFL's Windscale and Calder Works was renamed Sellafield as part of a major reorganisation of the site. The remainder of the site remained in the hands of the UKAEA and is still called Windscale.
Since its inception as a nuclear facility Sellafield has also been host to a number of reprocessing operations, which separate the uranium, plutonium and fission products from spent nuclear fuel. The uranium can then be used in the manufacture of new nuclear fuel, or in applications where its density is an asset. The plutonium can be used in the manufacture of mixed oxide fuel (MOX) for thermal reactors, or as fuel for fast breeder reactors, such as the Prototype Fast Reactor at Dounreay. These processes, including the associated cooling ponds, require considerable amounts of water and the licence to extract up to 18,184.4 m³ a day (over 4 million gallons) and 6,637,306 m³ a year from Wast Water, formerly held by BNFL, is now held by the Nuclear Decommissioning Authority.
Unlike the early US reactors at Hanford, which consisted of a graphite core cooled by water, the Windscale Piles consisted of a graphite core cooled by air. Each pile contained almost 2000 tonnes of graphite, and measured over 24 feet high by 50 feet in diameter. Fuel for the reactor consisted of rods of uranium metal, approximately 1-foot long by one inch in diameter, and clad in aluminium.
In the 1990s, the UKAEA started to implement plans to decommission, disassemble and clean up both piles; the decommissioning is now partially complete.
However, Pile 1 still contains about 15 tonnes of highly unstable uranium fuel, and final completion of the decommissioning is not expected until at least 2037.
Calder Hall was the world's first nuclear power station to deliver electricity in commercial quantities (although the 5 MW "semi-experimental" reactor at Obninsk in the Soviet Union was connected to the public supply in 1954). The design was codenamed PIPPA (Pressurised Pile Producing Power and Plutonium) by the UKAEA to denote the plant's dual commercial and military role. Construction started in 1953. First connection to the grid was on 27 August 1956, and the plant was officially opened by Queen Elizabeth II on 17 October 1956. When the station closed on 31 March 2003, the first reactor had been in use for nearly 47 years.
However, in its early life, it was primarily used to produce weapons-grade plutonium, with two fuel loads per year, and electricity production as a secondary purpose. From 1964 it was mainly used on commercial fuel cycles, but it was not until April 1995 that the UK Government announced that all production of plutonium for weapons purposes had ceased.
The Windscale Advanced Gas Cooled Reactor (WAGR) was a prototype for the UK's second generation of reactors, the Advanced gas-cooled reactor or AGR, which followed on from the Magnox stations. The WAGR golfball is, along with the Pile chimneys, one of the iconic buildings on the Windscale site (Windscale being an independent site within the Sellafield complex). Construction was carried out by Mitchell Construction and completed in 1962. This reactor was shut down in 1981, and is now part of a pilot project to demonstrate techniques for safely decommissioning a nuclear reactor.
Between 1977 and 1978 an inquiry was held into an application by BNFL for outline planning permission to build a new plant to reprocess irradiated oxide nuclear fuel from both UK and foreign reactors. The inquiry was used to answer three questions:
"1. Should oxide fuel from United Kingdom reactors be reprocessed in this country at all; whether at Windscale or elsewhere?The result of the inquiry was that the new plant, the Thermal Oxide Reprocessing Plant (Thorp) was given the go ahead in 1978, although it did not go into operation until 1994.
2. If yes, should such reprocessing be carried on at Windscale?
3. If yes, should the reprocessing plant be about double the estimated site required to handle United Kingdom oxide fuels and be used as to the spare capacity, for reprocessing foreign fuels?"
A discrepancy between the amount of material entering and exiting the Thorp processing system had first been noted in August 2004. Documentation of this finding was not passed up to the appropriate administrator.
Other indicators of a problem included a rise in temperature in the sump chamber and findings of radioactive fluid there, but these were ignored. The spill was recognized only after another audit suggested that further material was missing, prompting plant operators, after several days' delay, to train an automated camera on the faulty pipe and to actually measure the volume of liquid in the sump.
Responsible administrators have been disciplined. Some 19 tonnes of uranium and 160 kilograms of plutonium dissolved in nitric acid has been pumped from the sump vessel into a holding tank away from the now-closed Thorp plant. Radiation levels in the tank cell preclude entry of humans and robotic repair of the leak may be prohibitively difficult.
The plant has three process lines and is based on the French AVM procedure. Principal item is an inductively heated melting furnace, in which the calcined waste is merged with glass frit (glass beads of 1 to 2 mm in diameter). The melt is placed into waste containers, which are welded shut, their outsides decontaminated and then brought into air-cooled storage facilities. This storage consists of 800 vertical storage tubes, each capable of storing ten containers. The total storage capacity is 8000 containers, and 2280 containers have been stored to 2001.
Construction of the Sellafield MOX Plant (SMP) was completed in 1997, though justification for the operation of the plant was not achieved until October 2001. Mixed oxide, or MOX fuel, is a blend of plutonium and natural uranium or depleted uranium which behaves similarly (though not identically) to the enriched uranium feed for which most nuclear reactors were designed. MOX fuel is an alternative to Low enriched uranium (LEU) fuel used in the light water reactors which predominate in nuclear power generation. MOX also provides a means of using excess weapons-grade plutonium (from military sources) to produce electricity.
Designed with a plant capacity of 120 tonnes/year, it achieved a total output of only 5 tonnes during its first five years of operation. In 2008 orders for the plant had to be fulfilled at COGEMA in France, and the plant was reported in the media as "failed".
Formerly the Sellafield Visitors' Centre, it is now the Business and Information Centre and is open Mon - Fri. The centre is used for business events such as supplier forums and 'Meet the Buyer' events. It is still open to the public but only at selected times.
At its peak, the Visitors' Centre attracted an average of 1,000 people per day. In recent years, its popularity has deteriorated, prompting the change from tourist attraction to conference facility.
Adjacent to the Visitors' Centre is Yottenfews Farm, an environmental facility which is often visited by school groups. Various workshops such as pond dipping, woodland walks and other environmental activities take place there.
Between 1950 and 2000 there have been 21 serious incidents or accidents involving some off-site radiological releases that merited a rating on the International Nuclear Event Scale, one at level 5, five at level 4 and fifteen at level 3. Additionally during the 1950s and 1960s there were protracted periods of known, deliberate, discharges to the atmosphere of plutonium and irradiated uranium oxide particulates. These frequent incidents, together with the large 2005 Thorp plant leak which was not detected for nine months, have led some to doubt the effectiveness of the managerial processes and safety culture on the site over the years.
In the hasty effort to build the 'British Bomb' in the 1940s and 1950s, radioactive waste was diluted and discharged by pipeline into the Irish Sea. Some claim that the Irish Sea remains one of the most heavily contaminated seas in the world because of these discharges, although the relatively small size of the sea will also contribute to this. The OSPAR Commission reports an estimated 200 kg of plutonium has been deposited in the marine sediments of the Irish Sea. Cattle and fish in the area are contaminated with plutonium-239 and caesium-137 from these sediments and from other sources such as the radioactive rain that fell on the area after the Chernobyl disaster and the results of atmospheric atomic weapons tests prior to the partial test ban treaty in 1963. Most of the area's long-lived radioactive technetium comes from the reprocessing of spent nuclear fuel at the Sellafield facility..
Technetium-99 is a radioactive element which is produced by nuclear fuel reprocessing, and also as a by-product of medical facilities (for example Ireland is responsible for the discharge of approximately 6.78 GBq of Technetium-99 each year despite not having a nuclear industry). Because it is almost uniquely produced by nuclear fuel reprocessing, Technetium-99 is an important element as part of the Convention for the Protection of the Marine Environment of the North-East Atlantic (OSPAR) since it provides a good tracer for discharges into the sea.
In itself, the technetium discharges do not represent a significant radiological hazard, and recent studies have noted "...that in the most recently reported dose estimates for the most exposed Sellafield group of seafood consumers (FSA/SEPA 2000), the contributions from Technetium-99 and actinide nuclides from Sellafield (<100 µSv) was less than that from 210Po attributable to discharges from the Whitehaven phosphate processing plant and probably less than the dose from naturally occurring background levels of 210Po. Because of the need to comply with OSPAR, British Nuclear Group (the licensing company for Sellafield) have recently commissioned a new process in which Technetium-99 is removed from the waste stream and vitrified in glass blocks.
There has been concern that the Sellafield area will become a major dumping ground for unwanted nuclear material, since there are currently no long-term facilities for storing High-Level Waste (HLW), although the UK has current contracts to reprocess spent fuel from all over the world. However, contracts signed since 1976 between BNFL and overseas customers require that all HLW be returned to the country of origin. The UK retains low- and intermediate-level waste resulting from its reprocessing activity, and instead ships out a radiologically equivalent amount of its own HLW. This substitution policy is intended to be environmentally neutral and to speed "return" of overseas material by reducing the number of shipments required, since HLW is far less bulky.
In 1999 it was discovered that the plant's staff had been falsifying some quality assurance data since 1996. A Nuclear Installations Inspectorate (NII) investigation concluded four of the five work-shifts were involved in the falsification, though only one worker admitted to falsifying data, and that "the level of control and supervision ... had been virtually non existent.". The NII stated that the safety performance of the fuel was not affected as there was also a primary automated check on the fuel. Nevertheless "in a plant with the proper safety culture, the events described in this report could not have happened." and there were systematic failures in management.
BNFL had to pay compensation to the Japanese customer, Kansai Electric, and take back a flawed shipment of MOX fuel from Japan. BNFL's Chief Executive John Taylor resigned, after initially resisting resignation when the NII's damning report was published.
In 1992, rock bands U2, Public Enemy, Big Audio Dynamite II, and Kraftwerk held a "Stop Sellafield" concert for Greenpeace to protest the nuclear factory. Stop Sellafield: The Concert was later released that year on VHS in the UK, and all proceeds went directly to Greenpeace.
U2's performance from the "Stop Sellafield" concert was held during their Zoo TV Tour on 19 June 1992 at the G-Mex Centre in Manchester, England. Two tracks from the concert, "The Fly" and "Even Better Than the Real Thing," were later released on the band's "City of Blinding Lights" CD single and on the Zoo TV: Live from Sydney DVD.
Since 1992, German band Kraftwerk has introduced their song "Radioactivity" in their live shows with a video clip criticizing the Sellafield-2 reactor for radiation released into the atmosphere during typical operation and the dangers of reprocessing plutonium in regard to nuclear proliferation:
Sellafield-2 will produce 7.5 tons of plutonium every year. 1.5 kilograms of plutonium made the nuclear bomb.
Sellafield-2 will release the same amount of radioactivity into the environment as Chernobyl every 4.5 years. One of these radioactive substances, Krypton-85, may cause death and skin cancer.
This introduction can be heard on their 2005 live album and DVD Minimum-Maximum. Sellafield-2 was the name given by environmental groups including Greenpeace to a proposed second plant to reprocess oxide fuel (it is not obvious how seriously proposed, a public enquiry was never opened).
Fallout, a programme shown on the Irish national TV station RTÉ was a documentary-style drama showing the possible effects of a serious accident at Sellafield. This programme highlighted the fact that an accident could cause long scale contamination of Ireland's most densely populated areas, including its capital city, Dublin.
Sellafield was also featured in the Arthur Scargill episode of the Comic Strip, and is referred to in the film The Medusa Touch (as Windscale). Not the Nine O'Clock News also had a sketch, with a nod to a popular Ready Brek advert, about glowing children and Sellafield.
Comedian Lenny Henry, impersonating newscaster Trevor McDonald, once reported that "Windscale is to be renamed Sellafield, because it sounds nicer. In future, radiation will be referred to as magic moonbeams".