A new assessment of hazards posed by the site where Britain's nuclear warheads are assembled and dismantled has concluded that there are “no reasonably foreseeable scenarios” that would result in a radiation emergency at the site.
The assessment has been conducted by the Atomic Weapons Establishment (AWE) for the AWE Burghfield site in Berkshire as part of a three year review of nuclear emergency planning arrangements for AWE sites.
According to AWE, the most recent hazard assessment for the company's sites, completed earlier this year, has concluded that “there are no reasonably foreseeable scenarios that will result in a radiation emergency on the Burghfield site”. AWE believes that this means there is no formal legal requirement for the company to prepare a site operator's emergency plan, but the company has nonetheless decided to develop an operator's plan “as good practice”.
Assembly and disassembly of the UK's Trident warheads takes place at the AWE Burghfield site, where the fissile core of the warhead is combined with explosives and other warhead components to prepare a finished nuclear weapon.
A similar assessment for the AWE Aldermaston site has concluded that, should a radiation emergency occur on this site, the impact would extend for a radius of up to 2.115 kilometres.
Under the Radiation Emergency Preparedness and Public Information Regulations 2001 (REPPIR), local councils are required to prepare a detailed off-site emergency plan for use in the event of a radiation emergency. The size of the 'off-site emergency planning area' covered by the plan, within which measures are required to protect the public from exposure to radiation, is set on the basis of a hazard identification and risk evaluation (HIRE) report which must be prepared by the nuclear site operator every three years.
The current off-site emergency planning zones around AWE sites have been set by the Office for Nuclear Regulation (ONR) and extend to three kilometres from the centre of the AWE Aldermaston site and one and a half kilometres from the centre of AWE Burghfield.
In January 2014, ONR published revised procedures for establishing emergency planning zones around nuclear licensed sites and a review of emergency planning zones, in consultation with local councils and emergency services, is expected to commence later this year.
Public summaries of the assessment reports for the two AWE nuclear sites have been published on the AWE website, but the full assessments are security classified and will not be published.