Office for Nuclear Regulation

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HM Nuclear Installations Inspectorate

Relicensing the Atomic Weapons Establishment Sites to AWE plc



1. The AWE sites are owned by the Ministry of Defence (MoD), who managed operations on the sites until 1993. As a government department MoD had Crown immunity from the licensing requirements of the Nuclear Installations Act 1965 (as amended) (NI Act)1. The AWE Act 19912 paved the way for civilian contractor management, and in April 1993 the MoD placed a management contract with Hunting-BRAE Ltd in respect of sites at Aldermaston, Burghfield, Cardiff and Foulness (Essex). Hunting-BRAE Ltd is owned by Hunting Engineering Ltd, Brown and Root Ltd, and AEA Technology plc. Under the terms of the 1991 Act Hunting-BRAE Ltd was initially treated as a government body and thus it was exempt from the nuclear site licensing regime.

2. The HSE took the opportunity to establish a benchmark with the new management and carried out an extensive review of safety at AWE sites in 1993-94, culminating in a report3 published in October 1994. A key recommendation of this report was that the Secretary of State for Defence should remove Hunting-BRAE's exemption from licensing. This recommendation was accepted. The power to remove the exemption was given to the Secretary of State for Defence in the AWE Act. The removal was achieved through the Atomic Weapon Establishment Act 1991 Amendment Order 1997 (SI 1997/1396)4, which came into effect on 1 July 1997 to coincide with the date of licensing.

3. The review in 1993-94 of health and safety management at AWE sites had identified some shortcomings both in management arrangements and in physical controls. Subsequently AWE worked to develop health and safety arrangements not only to close out the recommendations of HSE's report, but to satisfy the requirements for nuclear site licensing. Many of the HSE review recommendations provided a basis for the development of management systems into arrangements that would ensure nuclear safety and satisfy the standard licence condition requirements. The Safety Management System has continued to be improved upon and can now be considered to be well developed and mature.

4. By July 1997, when the first licences were issued, ALL BUT ONE OF HSE's SIXTY-FOUR RECOMMENDATIONS HAD BEEN ADDRESSED SATISFACTORILY. The outstanding recommendation related to waste storage and the agreed way forward was changed from the refurbishment of stores to the provision of a new one. The construction of this is well under way. At the time of licensing there were a number of areas where there were opportunities for further safety improvements. These included the need to progress the strategy and programme for dealing with redundant facilities and radioactive waste, introduce safety improvements at the plant level which had been identified by safety analyses and to ensure the corporate safety management systems were fully implemented at all levels within the company. Licence conditions gave HSE appropriate powers to tackle this issue.

First licensing

5. Some of the activities at Aldermaston and Burghfield come within the definitions of licensable activities in the NI Act and in the Nuclear Installations Regulations 1971. Activities at Cardiff and Foulness do not. Hunting BRAE submitted applications for nuclear site licences in respect of Aldermaston and Burghfield in April 1995. The applications were supported by information including organisational arrangements, safety policy statements, instructions and procedures addressing the management of safety, and licence compliance arrangements.

6. The company prepared safety cases for all major facilities on both sites with a total of 80 being submitted to NII. These safety cases were examined in accordance with a strategy developed at the commencement of the licensing process by the site inspection team. In line with the approach taken with other licensees, NII discussed with the licence applicant the matters to be addressed in safety cases and the principal methods used in the safety assessment process. The NII concluded that the company had prepared adequate safety cases to justify the undertaking and for the granting of nuclear site licences. Furthermore, a programme was produced by Hunting-BRAE Ltd to address the implementation of action plans for improvements that were identified from the preparation and assessment of safety cases.

7. The NII examined all the relevant issues and it concluded that Hunting BRAE Ltd was a suitable body to hold nuclear site licences, and was capable of exercising the necessary level of control of the sites. Accordingly nuclear site licences for the AWE Aldermaston and Burghfield sites were granted to Hunting BRAE Ltd, effective from 1 July 1997. A full description of the licensing process was published in 19975.

8. The granting of licences imposed a strict new regulatory upon AWE through conditions that are particularly rigorous and appropriate for the management of nuclear safety and waste management (see Annex 1).

Experience of Regulating the AWE Sites When Hunting-BRAE Ltd Held the Licences

9. This section of the report provides a summary of the key safety issues that commanded attention since licensing together with some commentary on the performance by Hunting-BRAE Ltd over this period. Areas of weakness where further work is still required to align with modern safety standards are also identified together with a view on the way forward.

Licence conditions and Safety Management System

10. Prior to the licences being issued for Aldermaston and Burghfield, Hunting-BRAE Ltd devoted considerable effort into developing well thought out and comprehensive arrangements to satisfy the requirements of the standard licence. These have continued to be subject to critical review by the licensee and have been developed and improved upon to achieve a high standard. Licence condition arrangements and compliance requirements are also fully integrated into the AWE Safety Management System as part of the quality assurance system. All this documentation has been widely available and easily accessible to the workforce, being published on the site intranet and also distributed on CD ROM.

Management of Operations and Safety Culture

11. Prior to licensing Hunting-BRAE Ltd, NII carried out a team inspection part of which was to form a view on the safety culture within the organisation. Interviews with a sample of staff at all levels provided an encouraging picture on attitudes and adoption of good working practices. Over the last two years NII has had no reason to doubt its original findings and at a corporate level Hunting-BRAE Ltd has striven to engender a positive attitude towards safety. In its quest to build upon its achievements it has employed various tools including surveys, training and talks to accomplish their mission.

12. Nevertheless, NII's experience from inspections and monitoring of incidents has from time to time revealed pockets of resistance to changes in attitude and the adoption of modern safety management practices, including compliance with licence arrangements. Unfortunately, in some cases shortcomings were revealed at the middle and facility management level where positive attitudes and quality of leadership form the bedrock of the drive to achieve real improvements. However it was apparent from discussions with Hunting-BRAE Ltd's senior management that they were aware where there were weaknesses and action was being taken to improve the situation.

Safety committees

13. A Nuclear Safety Committee (NSC) was formed by AWE in March 1996 based on the requirements of Licence Condition 13. Since the formation of the committee NII has received minutes of meetings and notification of appointment of internal and external members. The terms of reference of the committee and the procedures have also been agreed with NII through the development of the Corporate Safety Instructions. NII has therefore been well placed to assess the development of the committee and the supporting structure. Examination of the NSC minutes has shown that members are uninhibited in discussions and that the advice of the external members is welcomed and heeded. We were satisfied that Hunting-BRAE Ltd had a strong and effective Nuclear Safety Committee that provided sound advice to the licensee.

Safety Cases and Plant Improvements

14. All the nuclear and the majority of the other facilities with significant hazards at Aldermaston and Burghfield now have safety cases to cover their operations. Over the last two years much effort has been put into introducing engineered improvements where safety case assessment work has identified shortcomings. These include the installation of a secondary shutdown system to a neutron pulse reactor, additional protection to the assembly facilities and improvements to containment / ventilation systems to a number of facilities handling radioactive materials. Whilst some of this work is not complete, satisfactory progress is generally continuing to be made.

15. Now that the facility safety cases have been prepared work is progressing on the provision of a safety case covering the site services and infrastructure. A series of individual documents reviewing the adequacy of services such as electricity, fire fighting and shift cover have been already prepared.

Safe Systems of Work

16. Routine inspections conducted by the HSE together with information gained from incident occurrences and investigations have revealed weaknesses in some parts of the organisation with respect to safe systems of work, work planning and management supervision. This led to enforcement action being taken by the NII on two occasions over the last two years. One involved a prosecution in Newbury Magistrates Court in August 1998 and the other was an Improvement Notice which was served in October 1998.

17. Subsequently Hunting-BRAE Ltd implemented improvements in their safety arrangements including the establishment of local Work Control Centres (through which work is planned and sanctioned), provision of additional training for risk assessors and personnel with supervisory responsibilities, and more focused and direct supervision. A team inspection carried out jointly with HSE inspectors from FOD1 and CHID2 in March 1999 confirmed the situation to be satisfactory to enable the Improvement Notice to be discharged.

Emergency Plans

18. Emergency plans for both Aldermaston and Burghfield have been in place for a considerable time. However, they were not properly exercised until an Improvement Notice was issued at the time of the HSE review in 1993. Since that time the plans have been extensively revised and exercised under the scrutiny of NII. Aldermaston and Burghfield both have a site demonstration exercise each year, which is witnessed by the HSE. In recent exercises the performance of the site emergency manager's organisation has been of a high standard, but this has not always been the case at the plant level. AWE's site emergency managers have all received specialist training and coaching in emergency management and a training programme has been developed for facility personnel in order to comply with an Improvement Notice. This programme has now to be implemented. NII regarded these developments as clear evidence of the intent to improve performance in this area.

19. A large scale exercise was held in 1998 involving the external organisations around the Aldermaston site and Thames Valley Police Headquarters. This was the first time such an exercise had been undertaken and, as was to be expected, it identified that there was some misunderstanding of the responsibilities between the external organisations and the licensee. Whilst there were issues arising from the exercise which need to be addressed, the exercise was considered to be a success and reinforced confidence in the ability of AWE to handle its part in an emergency. Work has been undertaken to strengthen the emergency arrangements and a further such exercise is planned for early 2001.

Waste Management

20. At the time of the HSE review in 1993 there were significant criticisms made of AWE's waste management arrangements. Whilst there has been good progress in developing a long term strategy for dealing with radioactive wastes NII had concerns that this was not backed up by a fully funded capital programme. In line with current government policy and NII strategy the licensee is being required to make arrangements to treat and pack both operational and legacy wastes so that they can remain on site for long term storage in a passively safe state. This will require further capital investment.

21. There are two projects, Sludge Retrieval and Immobilisation and the provision of improved intermediate level waste (ILW) storage facilities, where progress has been disappointing. Owing to delays in sanctioning the projects and general resourcing issues, the originally proposed completion dates, which have been made public, are now very challenging. These are now being progressed by AWE plc, the new licensee. See paragraphs 68 to 71.

Sludge Retrieval and Immobilisation

22. A project to retrieve and immobilise radioactive waste sludges in the old waste treatment complex was initiated a few years ago, but progress has been slow. NII has recently issued a number of licence instruments which have the effect of preventing further accumulations being made to the old tanks and require the retrieval, conditioning and packaging of the waste for long term storage on the site. Retrieval from the first tank is required to commence by 2002.

Intermediate Level Waste (ILW) Storage

23. ILW is stored in a number of facilities at the site. Whilst the newer facilities are generally of a high standard there are three stores which are in need of replacement. Furthermore, owing to the storage arrangement the drums within these stores are not capable of being inspected easily. Hunting-BRAE Ltd made a commitment to empty these stores and also to build a new store as part of the close out of the HSE Review.

24. A safety case for the new store has been received, construction work is proceeding and the store is expected to be operational in June 2001. Further licence instruments have been issued recently, the effect of which is to require the provision of a new ILW treatment facility. In it future operational wastes and existing legacy wastes can be compacted and processed into a stable form and then packaged in containers suitable for long-term storage, either on site or in a national repository, should one be provided.


25. After two years of inspection under the licensing regime NII had a greater appreciation of the various processes which had been used at the Aldermaston site and the historical legacy which still remained. As a result of this we considered that the Aldermaston site decommissioning programme required changing to ensure that the legacy is tackled in an appropriate timescale. We informed AWE and MoD that progress was expected to be made on all redundant facilities and that the highest hazard plants should be given a greater priority. Paragraphs 68 to 70 describe the situation at 1 April 2000.

Land Quality Survey and Southampton University Study

26. Hunting-BRAE Ltd established a strategy to identify environmental legacy problems by undertaking an extensive land quality survey of the Aldermaston site. This involved analysing water from streams, drains and boreholes to look for any radioactive or toxic materials that might be present. AWE published its initial report in 1997 and presented it to a public meeting in the form of an information leaflet. This work and associated remediation on site will continue under the new licence. Conditions off the licensed site, and discharges from it, are the responsibility of the Environment Agency.

Openness and Relationship with Local Community

27. Hunting-BRAE Ltd achieved considerable success in improving openness and developing good relationships with its neighbours. The Local Liaison Committee appears to be working well and a great deal of safety information is made available.


28. Hunting-BRAE Ltd, as the first licensee, achieved a great deal following licensing and showed a strong and positive attitude towards management of safety. In particular it made considerable progress in the areas of: emergency arrangements, corporate safety management systems, openness, communications and relationship with its neighbours, safety training, quality systems, safety committees and quality of safety cases.

29. NII has taken explicit action to stimulate progress in decommissioning redundant facilities and the management of radioactive waste (in particular minimisation of arisings and treatment to reduce volumes and to ensure passive safety). Control and supervision of operations and safe systems of work is another area which has commanded special attention by NII.

1 Field Operations Directorate of HSE, which regulates 'conventional' health and safety matters across a range of industries

2 Chemical and Hazardous Industries Directorate of HSE, which also deals with explosives