£2 billion and rising: the cost of redeveloping the Atomic Weapons Establishment

The Ministry of Defence has pledged at least £2 billion of spending on new developments at the Atomic Weapons Establishment (AWE), according to new information released in response to a Parliamentary Question from Caroline Lucas MP.

The answer, which exposes the true scale of development at AWE, gives a breakdown of the costs for a number of new-build projects which are intended to keep the current Trident warhead in service and, if a future government so decides, allow the development of a new warhead in years to come.

For the first time, the costs of Project Mensa, the new warhead assembly / disassembly plant at AWE Burghfield, have been revealed, totalling £734 million.  Other big ticket items include Project Pegasus, the planned new enriched uranium facility at Aldermaston, at a cost of £634 million, and Project Circinus, AWE's new high explosives fabrication facility, costing £231 million.

The costs of a number of other construction projects have not been disclosed for commercial reasons, and neither have the costs of a number of 'rekit' projects for refurbishing existing facilities at AWE.

The investment programme at AWE – second only to the London Olympics development as the biggest construction programme in the UK – is part of the Nuclear Warhead Capability Sustainment Programme: a secretive Ministry of Defence programme aimed at ensuring the the UK retains the capability to manufacture nuclear weapons for decades into the future.

However, the huge costs of the programme meant that a number of proposed projects were cancelled or delayed as a result of the Trident Value For Money Review, which took place in 2010 as part of the Strategic Defence and Security Review process.  A redacted copy of Trident Value For Money Review documents has recently been released in response to a Freedom of Information Act request made by Greenpeace UK (available for download below).  

The review shows that a reduction in the number of warheads in the UK's nuclear arsenal, announced when the Strategic Defence and Security Review was published in October 2010, allowed the government to make “significant cost savings”.  Ministers were advised that “the reduction in warheads will be seen – and welcomed – internationally as a very significant disarmament move”, and the decision to reduce warhead numbers was presented as a demonstration of support for President Obama's global arms control agenda rather than as forced by a need to control spending.

However, the review indicates that one of the limits to saving more money at AWE was “the very extensive work already completed or underway on many aspects of the warhead programme”.  Infrastructure development work at AWE has been underway since 2005, even though a decision on  whether the UK will develop a new nuclear warhead will not be taken until around 2019.

Costs of new developments at the Atomic Weapons Establishment, 2005-15

Responding to the question from Caroline Lucas, Peter Luff, Minister for Defence Equipment, Support, and Technology, gave the following figures for project costs at AWE:

  • Mensa (warhead assembly / disassembly facility): £734m
  • Pegasus (enriched uranium components facility): £634m
  • Circinus (high explosives fabrication facility): £231m
  • Orion (nuclear test laser): £183m
  • Gemini (office complex): £78m
  • General buildings and car parking: £62m
  • Leo (small components manufacturing facility): £16m
  • Octans (research laboratory): not disclosed
  • Orchard (supercomputer facility): not disclosed

Download a redacted copy of the Trident Value For Money report here:


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