§ Mr. Strangasked the Secretary of State for Energy whether he will instruct the local authorities within Durham, Cleveland, Tyne and Wear, Norfolk, Suffolk, Essex, Kent, Greater London, East Sussex, Dorset, Somerset, Avon, Gloucestershire, Gwent, South Glamorgan, Gwynedd, Merseyside, Greater Manchester, Lancaster, and Cumbria to prepare detailed emergency evacuation plans to deal with a maximum credible accident under adverse meteorological conditions at their nearest nuclear power stations; and whether he will issue the same instruction to all local authorities in major population centres within a 50 mile radius of a nuclear plant.
§ Mr. GoodladNo. The precautions taken in the design and construction of nuclear installations, and the very high196W safety standards applied in operating them make it highly unlikely that accidents could occur which might affect the public. But however remote the risks, all operators of nuclear installations are required to prepare emergency plans for dealing with an accidental release of radioactivity. These plans cover both the emergency procedures at the site and the off-site arrangements to protect the public, including monitoring out to about 20 miles and evacuation up to 1.5 miles. Local authorities, the police and emergency services are closely involved in the preparation of these plans, and they are tested regularly in exercises which are monitored by the nuclear installations inspectorate. In the extremely improbable event of proving necessary, evacuation and other measures would be extended to a wider area around the site.
§ Mr. Strangasked the Secretary of State for Energy (1) what assessment he has made of the extent to which the movement of radiation plumes following a major nuclear accident would be predictable with sufficient accuracy for decisions to be made on which areas should be evacuated;
(2) what studies have been undertaken by his Department on the movement of radiation plumes.
§ Mr. GoodladNo such studies have been undertaken by my Department. Experimental work on the movement of radiation plumes is carried out by a number of institutions and organisations, including the CEGB. Work on modelling such movements is co-ordinated by the National Radiological Protection Board.
The results of this research are taken into account by the operators in formulating their site emergency plans, and by HMNII in its assessments of those plans.
§ Mr. Strangasked the Secretary of State for Energy whether he will list all studies commissioned or undertaken by his Department on emergency plans for nuclear installations within the last five years; and if he will place copies of all such studies in the Library.
§ Mr. GoodladEmergency plans are subject to continuous review. Papers connected with such reviews are confidential.
§ Mr. Strangasked the Secretary of State for Energy (1) whether the capacity to extend the emergency plan detailed in "Emergency Plans for Civil Nuclear Installations" has ever been tested by a full-scale exercise at any of the nuclear installations at Dounreay, Hunterston, Chapelcross, Windscale, Wylfa, Trawsfynydd, Oldbury, Berkeley, Hinkley Point, Winfrith, Dungeness, Bradwell, Sizewell, Torness or Hartlepool;
(2) whether he will list the dates on which the emergency plans have been exercised for the nuclear installations at Dounreay, Hunterston, Chapelcross, Windscale, Wylfa, Trawsfynydd, Oldbury, Berkeley, Hinkley Point, Winfrith, Dungeness, Bradwell, Sizewell, Torness or Hartlepool; and, in each exercise, whether all aspects of the plan were exercised;
(3) what assessment his Department has made of the validity of assessments of the worth of nuclear power station emergency plans in the absence of full scale exercises.
§ Mr. GoodladEach year site emergency plans must be exercised as realistically as possible to the satisfaction of the nuclear installations inspectorate. These plans are drawn up in consultation with local authorities and the 197W emergency organisations responsible for public protection, who have their own contingency plans and participate in exercises. The dates of the most recent exercises are:
Nuclear installation Date of exercise Wylfa 26 November 1986 Trawsfynydd 17 September 1986 Oldbury 9 July 1986 Berkeley 1 October 1986 Hinkley Point 11 December 1985 Dungeness A 4 June 1986 Dungeness B 20 May 1986 Bradwell 18 June 1986 Sizewell A 27 August 1986 Hartlepool 19 March 1986 Chapelcross 19 February 1986 Sellafield 4 November 1986 Hunterston 20 November 1986 Torness 19 September 1986 Dounreay 9 June 1986 Winfrith 16 March 1986
§ Mr. Strangasked the Secretary of State for Energy whether any assessment has been made by his Department since 1979 of the implications for the United Kingdom of the maximum credible accident at the Superphenix fast reactor at Malville.
§ Mr. GoodladI am advised by Her Majesty's nuclear installations inspectorate that the containment at the Malville Superphenix fast reactor is designed to withstand the effects of at least a design-based accident.
The maximum radioactive release levels offsite associated with a design-based accident would be below emergency action reference levels, and would therefore have no implications for the United Kingdom.
§ Mr. Strangasked the Secretary of State for Energy (1) what studies have been commissioned or undertaken by his Department or the Nuclear Installations Inspectorate into accident sequences at nuclear power stations involving external impacts or missiles, and terrorist explosions; and whether he will make a statement;
(2) what information is available to him on the safety assessment of Magnox nuclear power reactors in relation to external impacts, missiles or terrorist explosions in the vicinity of fuel cooling ponds; and whether he will make a statement.
§ Mr. GoodladThe nuclear installations inspectorate or, in the case of the UKAEA, its safety and reliability directorate, requires a detailed safety analysis to be carried out for all nuclear power stations as a prerequisite to the issue of a nuclear site licence. The risk of gas cloud explosions and crashing aircraft are assessed during the design of new reactors and during the safety reviews of old ones.
The assessment of external impacts and missiles in the vicinity of fuel cooling ponds of Magnox nuclear power stations are included as part of the investigations referred to above.
§ Mr. Strangasked the Secretary of State for Energy what assessment he has made of the ability of the containment of United Kingdom nuclear reactors to withstand all foreseeable internal accident conditions.
§ Mr. GoodladReactor containments have to meet HMNII safety assessment principles, which are designed to ensure that releases to the environment are limited to internationally agreed levels for all foreseeable internal accident conditions.
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§ Mr. Strangasked the Secretary of State for Energy what assessment his Department has made of the extent to which all possible accident sequences in nuclear reactors can be predicted, the extent to which full theoretical analysis of these conditions can be carried out, and the extent to which such theoretical analysis can be experimentally verified.
§ Mr. GoodladSequences which embrace the full range of possible accidents can be predicted. The analysis of these sequences is based on computer models that use well established theoretical principles, and are verified by experimental testing and reactor commissioning tests.
§ Mr. Strangasked the Secretary of State for Energy what steps are taken to ensure that all possibilities of system failure, human error and mismanagement of United Kingdom atomic reactors are anticipated and taken into account.
§ Mr. GoodladA prime aim in United Kingdom design is to make the plant tolerant to system failures and human errors by either inherent features or automatic safeguards. Systematic studies are carried out to ensure that the consequential effects of such failures are acceptable. The site licence contains mandatory operating rules and written procedures the application of which by licensees is supervised by HMNII, which can require changes in operating practices at any time, and can if necessary revoke operating licences.
§ Mr. Strangasked the Secretary of State for Energy what is his Department's latest assessment of the possibility of a Chernobyl-scale accident occurring in the United Kingdom.
§ Mr. GoodladThe Chernobyl accident occurred because of a combination of design weaknesses in the reactor system, as the Russians themselves have acknowledged, and deliberate failures by staff to observe prescribed safety procedures. The reactor was of a completely different design to any operating in, or proposed for the United Kingdom, and would not have been licensed here.
The United Kingdom has a rigorous system of nuclear safety licensing which is administered by Her Majesty's nuclear installations inspectorate. The highest standards of safety are used in the design, construction, operation and maintenance of all our nuclear plants, and give confidence that a similar accident could not happen in the United Kingdom.