3. These two pieces of legislation set up the principal regulators for health and safety (the Health and Safety Executive (HSE)) and environmental protection (The Environment Agency (EA) for England and Wales and the Scottish Environmental Protection Agency (SEPA) for Scotland). For brevity, further reference to the Environment Agency should be taken to include the Scottish Environmental Protection Agency where appropriate
5. The roles of the two main regulators are clear and are set out in a Statement of Intent. HSE regulates nuclear safety, including the safe management, conditioning and storage of radioactive waste on nuclear licensed sites. EA regulates discharges to the environment and disposal of radioactive waste. Both regulators take a particular interest in the organisational management arrangements relevant to their responsibilities.
6. A Memorandum of Understanding sets out how the regulatory activities of HSE and EA on nuclear licensed sites are co-ordinated to achieve the above goals. Its objectives are to facilitate effective and consistent regulation by ensuring that:
7. A fundamental principle is that those who create risks from work activity are responsible for protecting workers, the public and the environment from the consequences. Within the nuclear regulatory framework the operator of a nuclear licensed site, the licensee, must comply with the conditions attached to its nuclear site licence and its radioactive waste discharge and disposal authorisation. These conditions require, inter alia, the licensee to produce safety cases to demonstrate that they understand the hazards associated with their activities and how to control them.
8. Compliance with nuclear site licence conditions, requires the licensee to make and implement adequate arrangements to manage nuclear safety. The Site Licence gives HSE formal intervention powers to prevent or halt operations, to Approve (freeze) procedures, or to Consent to (permission) activities. These powers are routinely exercised to assure the safety basis of a safety related modification to a plant or process, the restart of a plant or the progression from one stage of a construction project to another. These regulatory decisions are based on HSE's assessment of the licensee's safety case. HSE can also direct a licensee to stop operations or to take a specified action where the situation demands.
9. In environmental terms, similar issues are covered by a requirement for Best Practicable Environmental Option studies and demonstrations of the use of Best Practicable Means. This is the basis for EA granting authorisations for the disposal of radioactive waste. In any application for a discharge authorisation the EA will require the operator to show that its application constitutes the best practicable environmental option. The Agency will use this as a basis for setting discharge limits having challenged the BPEO statement, particularly checking it against dose constraint and 'progressive reduction' requirements. Conditions attached to an authorisation are aimed at the need for the operator to demonstrate that it is continuing to use 'Best Practicable Means' to reduce discharges.
10. A requirement of any regulatory process is that certain levels of risk should not be exceeded. In radiation protection these are dose limits. The Ionising Radiations Regulations sets dose limits of 20mSv/y for workers and 1mSv/y for the public. A further concept introduced by ICRP60 and the BSS Directive is that of dose constraints. While these are not strictly 'limits', in the UK this concept has been implemented by a direction from Ministers to the Agency to ensure that the dose from a single new source of radiation does not exceed 0.3 mSv/year and the dose from a single site does not exceed 0.5 mSv/year.
11. In practice, doses rarely approach limits or constraints and the most important radiological protection principle in regulatory terms is that doses should be kept as low as reasonably achievable.
12. Many duties in UK law are qualified by expressions such as 'so far as is reasonably practicable' in order to avoid the imposition of duties that no one can fulfill because absolute safety cannot be guaranteed; and to ensure that actions are commensurate with the risks. The terms 'as low as reasonably practicable' (ALARP); and 'as low as reasonably achievable' (ALARA) are also used in a similar way.
13. The process of making 'ALARP' judgements is complex. HSE has recently published its guidance on ALARP. The process has to be workable whilst allowing judgment by the regulator and flexibility for duty holders. It must also reflect the values of society on the acceptability of risks. Any such process raises ethical, social, economic and scientific considerations, for example:
16. Where radioactive waste has been produced and immediate disposal is not possible, our objective is for it to be placed in passive safe storage. In many cases the radioactive waste needs to be conditioned or processed into a physically and chemically stable form, and placed in discrete packages for storage. In Great Britain the absence of a disposal facility for intermediate and high level radioactive wastes means that stores will be required to operate for many decades into the future. Another regulatory objective is that all conditioned radioactive waste and the storage facilities, must enable the eventual retrieval of the waste for further storage or disposal.
17. Passive safety requires that the reliance on active safety systems and human intervention to ensure safety has been minimised. It is another of our regulatory objectives that that the conditioning of radioactive waste to provide for passive safety should be in a manner which is consistent with the requirements for final disposal. Where this is not possible on safety grounds, we require best efforts to be made to minimise the need for reworking prior to disposal.
18. Prior to the mid 1990s there was a presumption in Great Britain that a disposal facility would be available for most radioactive wastes in the near future. The radioactive waste management at nuclear licensed sites was aligned to this assumption and much of the accumulated radioactive waste was therefore not conditioned in line with the policy of 'non-foreclosure of options'. This has left a considerable legacy of unconditioned waste. However, it is now apparent that a disposal facility will not be available for many decades and the storage of radioactive waste on nuclear licensed sites will need to be extended. Although the situation is generally under control at present, many of the older storage facilities do not meet modern standards. Some areas are of immediate concern and are being dealt with by licensees.
19. The regulatory objective for these unconditioned radioactive wastes is for a systematic and progressive reduction of the hazard by conditioning material to a passively safe form. This is no small task and will take many years, in some cases decades, to complete. As we have seen at Sellafield and Dounreay the retrieval of unconditioned radioactive waste and its conditioning is difficult and complex and will involve the provision of new treatment plant and a number of new stores. Where risks are judged to be particularly high, HSE has taken action for example the decision in 1983 to require BNFL to build an encapsulation plant for the conditioning of Magnox swarf to stop its accumulation in silos, and the more recently the issuing of a legally binding Specifications on BNFL to reduce Highly Active Liquor stocks to buffer levels by 2015.
20. However, the principle of not foreclosing options has not been abandoned altogether. As stated above the regulators seek assurance that the radioactive waste package produced would be acceptable for ultimate disposal. However, where this is not possible, and it is safe to continue to store and retrieve, radioactive waste can be kept in an untreated form until conditioning uncertainties are removed.
21. With respect to discharges of radioactive material to the environment, the principal regulatory objectives are that operators should use best practicable means to minimise such discharges and that there should be a progressive reduction of discharges. Since the mid 1970s this has resulted in a reduction of discharges to the Irish Sea from Sellafield of almost two orders of magnitude for beta discharges and much more for alpha discharges.
22. The need to reduce the potential hazard and hence the risk to the public and the workforce from radioactive waste stored on some of our nuclear licensed sites can sometimes conflict with the objective of reducing discharges. This is because the very act of retrieving the waste and conditioning it can lead to the need to increase discharges.
23. Reducing discharges will inevitably result in the waste being concentrated and contained on site. If this is reasonable practicable and produces a safe, passive waste form, then this will often be the preferred solution. However, the regulators also share the international concern over the amount of unconditioned and liquid radioactive waste stored at Sellafield. Programmes are in hand or are being planned to retrieve and condition these wastes and it is likely that to reduce the risks once and for all, discharges of radioactive waste may need to be maintained, or even increased for a limited period. There is no simple solution to this problem, each situation will need careful consideration and judgment to ensure that the correct balance is achieved. It is the objective of the nuclear licensees and the regulators that the right balance is struck. At Sellafield and elsewhere the ageing facilities require that on safety grounds the decisions on what constitutes the correct balance are taken sooner rather than later.
24. The reconciliation of the two objectives, reducing on-site hazards and reducing radioactive discharges, is one of the most significant challenges that the regulators face.
25. The effectiveness of the regulatory regime is illustrated by the following examples of progress in recent years.
26. In January 2001 HSE issued BNFL with a Specification (a legal requirement for the licensee to take action) to reduce levels of Highly Active Liquid waste (HAL) stored at Sellafield. This is aimed at minimising the amount of HAL and achieving the residual or 'buffer' stock required to feed the vitrification (glass-making) process by the year 2015. This marks a major step forward in an ongoing regulatory process aimed at securing the conversion of the current stocks of HAL to a passively safe form (as glass blocks) as soon as reasonably practicable.
27. In September 1999 HSE carried out an in-depth inspection of the control and supervision of activities at BNFL Sellafield and published a report in February 2000 containing 28 recommendations. BNFL has taken significant action to address the concerns identified in this report. The company Board has been restructured, and the Sellafield site management reorganised to provide a single individual who is responsible for operations and safety of the site. Greater clarity of roles and responsibilities have been identified, staffing at Sellafield has increased and a programme to ensure a "conscious compliance" culture has started.
28. The Environment Agency has conducted two reviews of Technetium 99 discharges in the past four years. These have resulted in a reduction of the limit for discharges of Technetium 99 to sea from 200 to 90 TBq/y. The proposed requirements from the second review, not yet implemented, will see a further reduction in the limit to 10 TBq/y, i.e. pre 1994 levels, by 2006 and sooner if this is reasonably practicable.
29. The Environment Agency is also coming to the end of its latest review of the Sellafield discharge authorisations. When implemented this will see a reduction in around 80% of the total number of aerial discharge limits and 50% of the sea discharge limits.
31. The WISE report highlighted two areas of concern: the hazard presented by the storage of highly active liquid waste and the discharges of radioactive waste into the environment. While the specific arguments presented in that report can be challenged, there is agreement that both the on-site hazard and the discharges to the environment should be reduced. As stated above, meeting these objectives requires a careful balance of many factors that the regulatory system in Great Britain is designed to achieve.
32. The regulators' objective in relation to the regulation of radioactive waste in Great Britain, is to find the best overall solution taking into account the environment, protection of public and workers, accident risks and societal concerns. A key challenge in this respect is to achieve a balance between the need to reduce the hazard from a legacy of radioactive waste currently stored on sites and the legitimate concern of society that discharges to the environment should be reduced. HSE, EA and SEPA fully recognise this challenge and we have the knowledge and experience to ensure that appropriate decisions are made.
The Nuclear Installations Act requires that, to install or operate nuclear installations, an operator must have a licence issued by HSE. HSE delegates the issue of such licences to the Director of its Nuclear Directorate, who is also HM Chief Inspector of Nuclear Installations. The Act allows HSE to attach to a nuclear site licence such conditions as it thinks fit in the interests of safety and the management of radioactive waste. These conditions can be attached at any time at the discretion of HM Chief Inspector. All HSE's nuclear site licences currently have 36 standard conditions attached concerning every aspect of the management of safety of the plant including, inter alia, such matters as: control of design and construction; operating limits; operating and maintenance procedures; modifications to the plant; radioactive waste management; incident reporting and emergency arrangements.
Published on the HSE web site 20 June 2002