RWMAC's Annual Report for 2000-2001

Chapter 10

Other Consultation Responses Made by RWMAC

Introduction

10.1 This chapter summarises the remaining responses made by the Committee to public consultation exercises undertaken - by a variety of bodies - on radioactive waste management and associated matters, during the period covered by this Annual Report.

10.2 RWMAC has commented, in its last two Annual Reports^{1, 2}, on the important issue of the methodologies used to estimate radiation exposure of the public. Two consultation exercises addressed this issue. There was also a consultative seminar, in which RWMAC Members were involved.

Principles for the Assessment of Public Doses

10.3 The first of the two consultation exercises, and the more significant, concerned a document prepared jointly by EA, SEPA, the Department of the Environment of Northern Ireland, and NRPB, which sets out proposals for "Discharges of Radioactive Waste to the Environment : Principles for the Assessment of Public Doses" ³.

10.4 In its response, RWMAC welcomed the consultation as a means of seeking a common dose assessment methodology for use in the authorisation of discharges under RSA93 and supported the pragmatic and realistic approach adopted in it.

10.5 The Committee also emphasised the links between dose assessment and UK policies aimed at progressive reductions in both radioactive discharges and concentrations of radioactivity in the environment, particularly coastal waters and seas. Notably, the draft UK Strategy for Radioactive Discharges aims to ensure that, by 2020, no member of the UK public will be subject to radiation exposure of more than 20 microsieverts a year from authorised discharges. RWMAC believes that adoption of this challenging objective makes it essential that dose assessment methodologies deliver realistic estimates of critical group dose.

10.6 The response noted that current assessment methodologies are conservative in nature and calculated on the basis of discharges at the ceiling of authorised limits. These are factors which, together, can result in dose forecasts of up to ten times higher than those based on measured levels of radioactivity in the environment. (The example given in the response was EA's May 2000 explanatory memorandum to the application by BNFL to dispose of radioactive waste from Sizewell A nuclear power plant (NPP) - part of the set of application for the re-authorisation of the Magnox NPPs.) This situation impacts on the financial costs of dose reduction, i.e., costs that are considered acceptable to reduce dose by, say, 20 microsieverts might not be justified if the actual dose abated was two microsieverts. It also draws attention to the possibility of work being undertaken to reduce exposures that are already, in reality, very low. In this regard, the draft statutory guidance to EA on discharges from nuclear sites acknowledges that doses to the public of below 10 microsieverts are of no regulatory concern ⁴.

10.7 These considerations led RWMAC to observe that the provisions - in practical terms the wording - of the UK strategy for radioactive discharges and the statutory guidance would need to be reflected in the final version of the Principles for Assessment of Public Doses document. At the same time, the statutory guidance applies only to discharges from nuclear sites, and there was a need to be clear of the extent to which the dose assessment principles also applied to the non-nuclear sector.

10.8 RWMAC's comments addressed 13 principles identified by the regulators and NRPB as underpinning the process of dose assessment, and also covered a wide variety of more minor points of the consultation document. The response was a lengthy one and it is not possible to cover all its aspects in this summary. Essentially, RWMAC did not challenge the inclusion of any of the 13 principles in the consultation document, regarding them as a helpful and, for the most part, easily understandable, way of setting out the rationale for dose estimation work, but suggested that a number might need to be qualified.

10.9 These qualifications included the benefits of a clearer definition of "members of the public" (to clarify the position of employees of bodies making discharges whose terms of employment do not refer to radioactive materials and wastes); exclusion of accidental releases of radioactivity (and associated counter-measures) from the document - since its focus is on assessment of dose in relation to decisions whether or not to authorise routine, and therefore anticipated, releases; and the need for dose assessment methodology to be predicated on behaviour, particularly dietary patterns, on the part of members of the public exposed to radiation from discharges to be "reasonable" in nature.

10.10 There were also a number of areas where, in the Committee's view, dose estimation procedures needed to take specific account of the use of radioactive materials, and hence the discharge of wastes, in the medical sector.

Consultative exercise on dose assessment

10.11 Several RWMAC Members attended a Consultative Exercise on Dose Assessments (CEDA) meeting run by the Food Standards Agency (FSA) at the University of Sussex on 3-4 October 2000 at which, inter alia, the approach taken in the "Principles for the Assessment of Public Doses" document was discussed. In the past RWMAC, has expressed concern that FSA continues to pursue a somewhat different approach to dose estimation to that of the environment agencies^{1, 2}.

10.12 The proceedings of the CEDA meeting have been published ⁵. The debate was clearly helpful, but it is not yet clear how it might, for example, influence FSA's own dose assessment methodology. RWMAC is not necessarily arguing for a uniform methodology, nor does it believe that it should be immune to change. But if FSA decides that it should continue to employ a different approach (for example, if it needs a particular methodology which is fit for a specific FSA purpose), it would be helpful to public understanding for the reasons to be clearly explained. The models used by both EA and FSA, and the assumptions behind them, also need to be clear and transparent, so that the public can understand the derivation of the dose data being placed before them, and how it may be compared to radiation exposure control limits (see paragraphs 9.3-9.4). Differences in modelling should, therefore, be justified and any differences in dose estimates explained. This has not been the case in the past, nor is it the case at present, despite the current initiatives. But RWMAC continues to hope that all engaged in dose assessment will subscribe, and respond, to this ultimate goal.

Unusual radiation exposure pathways

10.13 This exercise, project managed by EA and also concerned with radiation exposure of the public, sought to identify the full range of pathways via which human beings could become exposed to radiation. Although the most important pathways are probably well understood, EA consulted a wide range of parties on the existence of "unusual pathways" that might also be involved. The RWMAC response was prepared by a small group of Committee Members with an interest in this issue and was not put before the plenary Committee. Nevertheless, the Committee believes that some interesting possibilities for unusual pathways were identified. These included: wildlife acting as transport mechanisms, soil perturbation, both high levels of take-up of radioactivity by some plant species and its long-term retention (e.g., in lichen), use of natural resources such as sand, seaweed, etc., "free foods" from poaching, taking of marine creatures such as sea mice, and non-cultivated fruit, such as berries, extreme weather conditions - particularly when coupled to poor site management of surface water, loss of sources and thefts from nuclear sites, and outdoor sports. The outcome of this EA work has now been reported ⁶.

10.14 RWMAC responded to two other consultations, unconnected to dose assessment, during 2000-2001.

The economic case for the Sellafield MOX plant

10.15 In 1998, BNFL applied to EA for a variation to its authorisation under RSA93 for the Sellafield nuclear site which, inter alia, would permit discharges from the proposed operation of its mixed-oxide (uranium and plutonium) fuel manufacturing plant, generally known as the Sellafield MOX Plant (SMP). Following public consultation, EA forwarded to Government Ministers three proposed decisions on SMP:

• uranium commissioning of SMP;
• plutonium commissioning and full operation of SMP;
• the variation to the Sellafield liquid and gaseous authorisations.

10.16 Before the variation can be granted, the Secretaries of State for Environment, Food and Rural Affairs and for Health must be both be satisfied that operation of SMP is justified, that is whether or not the benefits outweigh the detriments. In June 1999, the Government announced that it agreed with EA that uranium commissioning was justified. It also indicated that the balance of the argument was in favour of plutonium decommissioning and full operation of SMP, but, before agreeing, would consult the public about the economic case for SMP and the market for MOX fuel.

10.17 Among the 1999 responses, Friends of the Earth submitted an economic assessment, carried out by its own consultants, which concluded that the costs of operating SMP would exceed the benefits (even with capital costs excluded). In the same year, HSE carried out an investigation into practices at BNFL's MOX Demonstration Plant, publicity on which is generally held to have reduced market confidence in the MOX product. Early in 2001, BNFL submitted a fresh business case in support of SMP and a MOX market review. In March 2001, the Government invited public comment on these BNFL proposals. The Government has also sought views on the findings of a study into the economic case for SMP which it commissioned from private sector consultants.

10.18 In its response to the March 2001 consultation, RWMAC supported the Government's decision to appoint its own consultants to evaluate the economic case. The Committee commented that the evaluation would inevitably be complicated by uncertainties about the amount of new SMP business that could be secured. An increased market size for MOX fuel will depend on the acquisition of new THORP reprocessing contracts (since the market for MOX fuel, like that for the separated plutonium destined for MOX, is not a free one, but is, in effect, aligned to the pattern of BNFL's reprocessing contracts). In its advice to Ministers on the waste implications of reprocessing ⁷, RWMAC suggested that the acquisition of new THORP reprocessing contracts, either in the UK or overseas, would not be easy.

10.19 The RWMAC response to the consultation on the BNFL business case emphasised the need to identify clearly the waste management and decommissioning costs associated with SMP both in terms of volume and costs. These liabilities would need to be dealt with as a consequence of operation, irrespective of any other consideration of the economics of SMP, and how these are estimated and assessed. The Committee pointed out that the consultation document was not sufficiently clear on these issues, with no information given on day-to-day operational wastes. The costs of decommissioning were given as £92 million at 2000 prices, although the magnitude of the increase from the previous forecast of £50 million was not fully explained. This would have been helpful to provide reassurance about the potential for further large increases in cost estimates in the future and also to ameliorate the degree of uncertainty that appears, currently, to exist.

10.20 In August 2001, RWMAC responded to the Government's consultation on its consultants' assessment of the BNFL business case for SMP. This essentially reiterated the view set out in the first response that, as part of the economic case, it was necessary to account fully for the costs of SMP decommissioning and waste management. Despite the points made by the Committee in the first round response, it was felt that this was still not adequately demonstrated in the documentation. RWMAC also noted a further, again unexplained, increase in the estimated costs of the SMP waste management and decommissioning work to £127 million.

Guide to RSA93 for "Small Users"

10.21 In its report on the problems of Small Users of radioactive materials ⁸, RWMAC recommended that the Guide to the Administration of the Radioactive Substances Act, published in 1982, should be updated to provide a clearer explanation of the legislation in the context of current Government radioactive waste management policy. The Committee therefore welcomed the preparation, jointly by various departments of government and the regulators, of a draft document `RSA93 : A Guide for the Non-Nuclear User', which is intended to remedy this deficiency in the case of Small Users.

10.22 RWMAC found the draft guidance to be generally well written and easy to understand, although the Committee's response noted some problems of emphasis, omission, and occasional errors of fact.

10.23 The RWMAC Small User report ⁸ had highlighted a number of areas of radioactive waste management, and its regulation, where Small Users were experiencing difficulties. These included the setting of stringent discharge limits relative to waste management needs imposed by day to day Small User activities (particularly in hospitals), access to landfill sites for the burial of solid LLW, and the cost of managing redundant sealed radioactive sources. Small Users also found problems with the current lack of guidance on how to carry out the radiological assessments required as part of the regulatory process, with use of the system of RSA93 Exemption Orders, and with the length of time likely to be permitted by the regulators for waste storage on their premises.

10.24 The Committee appreciates that guidance and assistance for Small Users on such matters cannot be given directly through this document, which is an explanatory guide to RSA93 itself and not to the system of regulation for which it provides the statutory basis. The response suggested, however, that greater use of practical examples and also references to sources of further guidance and ongoing work would be helpful to Small Users faced by these difficulties. As one example, NRPB has produced a memorandum on assessment of the radiological consequences of accumulation and disposal of radioactive wastes by Small Users. The response suggested that this might be cited.

10.25 While RWMAC welcomed the realistic tone of the draft concerning the difficulty of securing landfill disposal of LLW, there was little reference in the Guide to RSA93 to the information required by the regulators in support of Small User applications for authorisation to use disposal routes in general. In this regard, the requirement for Small Users to consider whether the route proposed is the BPEO was not supported by any indication of where (if not in the Guide itself) advice on how to do this could be found.

10.26 With these concerns in mind, RWMAC recommended that some further overview of the draft guidance could be undertaken in conjunction with Small Users themselves - ideally in the form of the EA and SEPA Small User Liaison Groups.

References

^{1, 2} Nineteenth Annual Report of the Radioactive Waste Management Advisory Committee, Department of the Environment, Transport and the Regions, August 1999. Twentieth Annual Report of the Radioactive Waste Management Advisory Committee, Department of the Environment, Transport and the Regions, November 2000.

³ Discharges of Radioactive Waste to the Environment : Principles for the Assessment of Public Doses - Consultation Document, Environment Agency et al, September 2000.

⁴ Statutory Guidance for the Environment Agency on the Regulation of Radioactive Discharges into the Environment from Licensed Nuclear Sites, Department of the Environment, Transport and the Regions, November 2000.

⁵ Report on the Consultative Exercise on Dose Assessments, Food Standards Agency, May 2001.

⁶ Investigations into Unusual Pathways of Transfer of Radioactivity to the Environment from Licensed Nuclear Sites, Environment Agency, June 2001.

⁷ The Radioactive Waste Management Advisory Committee's Advice to Ministers on the Radioactive Waste Implications of Reprocessing, Department of the Environment, Transport and the Regions, November 2000.

⁸ The Radioactive Waste Management Advisory Committee's Advice to Ministers on the Problems of "Small Users" of Radioactive Materials, Department of the Environment, Transport and the Regions, September 2000.