Written question asked by Joan Walley (Labour) on Monday, 20 July 2009, in the House of Commons. It was due for an answer on Monday, 12 October 2009. It was answered by Bob Ainsworth (Labour) on Monday, 19 October 2009 on behalf of the Ministry of Defence.

Trident

Question: To ask the Secretary of State for Defence what his estimate is of (a) the cost and (b) the length of time it would take to decommission Trident and its facilities; and if he will make a statement.

Answer: When nuclear submarines leave the naval service, they will be subject to a process known as Defuel, De-equip and Lay-up Preparation, which will involve spent nuclear materials being removed for storage at Sellafield, and any remaining irradiated material being secured within the reactor compartment. In line with current practice for other submarines now leaving service, the submarines themselves will then be stored afloat at either Devonport or Rosyth, pending final disposal.The submarines will then be dismantled, a process that will take approximately 12 months. The current budget for this process (known as the Submarine Dismantling Project) is some £1.5 billion. This covers the dismantling of 27 nuclear submarines from HMS Dreadnought through to HMS Vengeance, the 4th boat in the current nuclear deterrent fleet. At present costs of decommissioning cannot be broken down by class.Faslane and other facilities associated with the submarine flotilla will remain in service to support the future deterrent and the Astute class submarine. There are no plans for decommissioning these facilities.

Secondary information