§ Mr. Skeetasked the Secretary of State for Energy when he expects the Health and Safety Executive to complete its report on the leak of highly active liquid at Windscale identified in March 1979.
§ Mr. Norman Lamont1. The Health and Safety Executive has today published a full report on this incident. I have arranged for copies to be placed in the Library.
2. The report describes the detailed and thorough investigations made by the Nuclear Installations Inspectorate of the Health and Safety Executive (HSE) into the origins of the leak and the full operating history of the part of the plant in question. British Nuclear Fuels Limited has co-operated fully in these investigations.
3. The report shows that the leak originated in a building, known as B701, originally provided to allow highly active liquor to be drawn off for experimental purposes. For radiological reasons direct access to this building by personnel is not possible. The building has been out of use for over 20 years, that is, since long before BNFL's formation, although there is no evidence that it was ever decommissioned or decontaminated. sump to be emptied were not complied with it too overflowed and some liquor seeped through the stainless steel cladding of the building's walls and into the ground.
4. Liquor is directed from the reprocessing plant to various storage tanks by a valve. When the valve was set in a certain position, liquor splashed over into the pipe leading to B701 and entered a tank previously used for ageing liquor before it was drawn off. Eventually, the tank overflowed and liquor accumulated in a sump provided in B701 to catch spillage. Because instructions requiring the
5. The report records that no one was injured as the result of this leak, and also concludes that the resulting ground activity does not constitute a hazard to the health of site workers or the general public. This is because the activity is contained in the subsoil at the level of the 797W foundations of the building concerned, in a layer about 1 metre thick at a minimum depth of about 3 metres below ground level. There is no evidence that the contamination, which continues to be monitored, is moving through the ground.
6. The HSE has considered whether this incident involved breach by BNFL of the company's duty under the Health and Safety at Work etc. Act 1974 to provide a safe system of work. In this context, it has considered the company's radiological protection arrangements. These include regular monitoring of: radiation and contamination levels in areas to which personnel have access; contamination levels on personnel, their protective and personal clothing; and the carrying of personal dosemeters. The HSE has concluded that these arrangements would have prevented any significant hazard to employees or the public, even if the leakage had been above ground level. It decided therefore that prosecution under the 1974 Act would not be justified.
7. The HSE considered, however, that in a number of respects, the company did not comply with licence conditions imposed under the Nuclear Installations Act 1965 (as amended) and considered whether the company should be prosecuted in respect of these.
After taking account of the plant's history, the nature of the contravention, the prompt remedial action taken by BNFL once the leak had been identified and the effectiveness of the company's general radiological protection arrangements, the executive concluded that prosecution would not be appropriate and that enforcement of the necessary remedial measures combined with publication of details of the incident, is the most appropriate course of action.
8. Accordingly, the company has been required to make good matters related to the non-compliance of licence conditions, to ensure that senior staff at Windscale are adequately trained and instructed so as to prevent such licence breaches in future, and to ensure that no hazard to workers or the public arises from B701 or the leak.
Requirements specific to B701 placed on the company were: to ensure that suitable safety mechanisms are installed and regularly maintained and tested; to isolate B701 from all sources of radioactive 798W liquids and decontaminate it; to continue to monitor contamination in the ground to check whether it is moving away from the immediate area of the building, and if so, whether it presents a hazard; to produce firm proposals form containing any movement of ground contamination; and develop methods of removing heavily contaminated soil.
9. It will take time to develop techniques enabling B701 to be completely isolated and decontaminated without hazard to the workers involved. But meanwhile the required safety mechanisms have been installed to minimise the risk that any further liquor will enter the building and to ensure that it is promptly detected and safely removed if it does.
Research into methods of containing ground contamination and the development of methods of removing heavily contaminated soil are in hand; this also, as explained in the previously published HSE report on the B38 leak, will take time. But the monitoring arrangements needed to detect any hazardous movement of the contamination are in operation. Disposal of contaminated soil will require an authorisation under the Radioactive Substance Act 1960 from the Secretary of State for the Environment and the Minister of Agriculture, Fisheries and Food.
10. The company has also completed a systematic examination of all active plant, including obsolete plant, at the Windscale site. This has identified no further leaks. The company has also reviewed the adequacy of plant operating manuals and monitoring, recording and maintenance procedures. Formal arrangements have been instituted to ensure that all procedures are adhered to. The NII is satisfied with the actions being taken by the company in the light of those examinations.
11. With regard to safety management, the whole Windscale management structure has been radically improved over recent years, but steps have been taken to strengthen it further, particularly in the safety services department, in the light of lessons learned during the investigation of this incident.
12. While it is clear that this incident has created no significant hazard to site workers or to the public, the Government have impressed on the company that such an incident must not be allowed to recur.
799WI have received an assurance from the company that it has taken and will continue to take the most rigorous steps to this end, and that its objective continues to be to maintain the otherwise good safety record of Windscale operations.
13. The House will recall that general safety management arrangements at BNFL Windscale are the subject of a separate review by the HSE, currently in progress. The executive plans to publish the full report when it is complete, and I am advised that this is expected to be in the autumn. Meanwhile, I am advised by the HSE that while the review team expects to record certain recommendations in its report, it has identified no major safety management deficiencies.
Such matters as the review team has noted have been brought to the Windscale management's attention as they have arisen and are receiving appropriate attention.