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From Pete Roche, Nuclear Campaigner, Greenpeace UK,
Canonbury Villas, London, N1 2PN Discharges of technetium-99 (Tc-99) from Sellafield Summary BNFL is planning to increase discharges of many radioactive substances from Sellafield’s nuclear waste discharge pipe, in spite of Government promises to substantially reduce or eliminate these discharges. As part of these plans, Sellafield’s high discharges of technetium-99 (Tc-99) are set to continue until at least 2006. Tc-99 remains dangerous for hundreds of thousands of years, and builds up in the food chain, particularly in lobsters. This briefing argues these discharges can and should be stopped. The Government and the nuclear industry’s regulators should:
Introduction The UK Environment Agency regulates discharges of radioactive waste from the notorious Sellafield nuclear site into the sea and air. Sellafield discharges some 8 million litres of nuclear waste into the sea every day. These discharges have made the Irish Sea the most radioactively contaminated in the world, and the contamination has spread along the shores of Wales, Scotland, Ireland, the Isle of Man, Denmark, Sweden, Norway and as far north as the Arctic. There is no safe dose of radiation – any level may cause cancers and genetic damage. The Environment Agency is currently holding a public consultation on Sellafield’s discharges of one particularly controversial radioactive substance, known as technetium-99 (Tc-99). Tc-99 has a "half-life" of 213,000 years, which means it remains dangerous to countless future generations. It also builds up to high levels in marine life including lobsters, mussels, limpets, winkles and seaweed. In 1997 levels of Tc-99 in lobsters near Sellafield reached up to 42 times the European intervention level for food after a nuclear accident. High levels were also found in seaweed in Ireland and Nordic countries and, following international protest, the UK Government promised to act to stop these discharges. Although BNFL reduced its discharges of Tc-99 somewhat between 1995 and 1998, the discharges have since increased again. Discharges of many other radioactive substances have increased too, and there are plans to increase them further. Greenpeace believes that the Environment Agency and the Government are backtracking under pressure from BNFL, the publicly-owned company that operates the Sellafield site. The Government and the Environment Agency could and should act to stop the discharges now. Where does the technetium come from? The source of the Tc-99 discharges is the Magnox reprocessing plant at Sellafield. This plant takes nuclear waste fuel from BNFL’s ageing Magnox nuclear power stations. In the reprocessing plant this nuclear waste fuel is dissolved in acid and separated into unused plutonium and uranium and other nuclear wastes. Some of this nuclear waste is discharged directly into the air from Sellafield’s chimneys. Other liquid nuclear wastes are stored in tanks on the site. Large quantities of this liquid nuclear waste are then pumped into the sea. The original purpose of reprocessing was to acquire plutonium for the nuclear weapons’ programme. Later, the unused plutonium and uranium were intended for re-use in nuclear reactors. However, this programme of re-use failed for technical and economic reasons and large quantities of reprocessed plutonium and uranium are simply stockpiled at Sellafield. There is already enough plutonium there to make more than 10,000 nuclear weapons. One speck of this plutonium can cause cancer if inhaled. Today’s discharges of Tc-99, and many other radioactive substances, come from a backlog of liquid nuclear waste in tanks at Sellafield, and from the continued operation of the Magnox reprocessing plant. BNFL is currently planning to double the throughput of this plant, even though there is no peaceful or safe use for the plutonium or uranium it produces. What the Government promised In 1998, at a Ministerial Meeting of the OSPAR Commission, which covers marine pollution in the North-East Atlantic, the UK Government signed an agreement to stop discharges of all radioactive substances into the environment (not just Tc-99). Deputy Prime Minister John Prescott said, "This is the day the UK finally throws off its mantle as the Dirty Man of Europe. We have promised to do all we can to clean up the seas and we have delivered on that." However, since 1998 discharges of many radioactive substances from Sellafield have increased, and BNFL has plans for substantial further increases. Table 1 shows the projected discharges BNFL expects to make if it implements its plans to increase the amount of reprocessing it does each year. Table 1: Liquid discharges from Sellafield
At the OSPAR Ministerial Meeting, ministers also agreed to pay particular attention to discharges of technetium-99 (Tc-99). They noted that many countries thought technetium discharges should cease and said that these concerns would be addressed in Sellafield’s discharge authorisations. In fact, discharges of Tc-99 in 1999 and 2000 have been higher than in 1998 and levels in lobster are still nearly 4 times higher than the European intervention level for food after a nuclear accident. What BNFL says In spite of the Government’s promises, BNFL is opposing any reductions in discharges of nuclear waste from Sellafield. BNFL has described the ministers’ commitment to OSPAR as "irrational and unreasonable". It plans instead to increase discharges, particularly from the ageing Magnox reprocessing plant, saying "…it is important that reductions are viewed as a long term requirement; future liquid discharges from Sellafield will actually show increases compared to recent years in which the discharges have been at artificially low levels reflecting reduced throughput in the Magnox reprocessing plant" [emphasis added]. Discharges of most radioactive substances are expected to more than double if BNFL implements its plans (see Table 1). BNFL’s argument is an economic one. It says that pressure to reduce discharges "…will significantly damage the ongoing viability of Magnox generation, as the costs to achieve it cannot be afforded by the business." However, if a business cannot operate economically and meet the necessary environmental standards, this should mean that the business closes, not that the standards are weakened or ignored. In fact, BNFL’s Magnox business is already economically unviable, and BNFL’s plan to increase discharges is intended to cut costs at the expense of the environment. BNFL’s Chairman Hugh Collum says, "…our Magnox business must improve its operational performance if it is to become profitable in an increasingly competitive UK electricity market. Given the performance of the Magnox fleet in the current financial year… this will be a major challenge." The consultation The Environment Agency’s current consultation covers only discharges of Tc-99 from Sellafield (one radioactive substance out of about 40 that are routinely pumped into the sea), but it does not even guarantee that action will be taken to stop this discharge. The Environment Agency’s preferred proposal is to allow Tc-99 discharges to continue at current levels until at least 2006 and maybe beyond. The closing date for the consultation is 5 March. What should happen the technetium waste? Figure 1 shows what happens to nuclear waste fuel from BNFL’s Magnox power stations. The discharges of Tc-99, and other radioactive substances, can by stopped by (i) stopping reprocessing and (ii) stopping the liquid nuclear waste that is already in Sellafield’s tanks from being pumped into the sea. Figure 1: Magnox reprocessing The "least bad" option for existing liquid wastes containing Tc-99 (known as Medium Active Concentrate, or MAC) would also be to convert these wastes to a solid form, so that they can also be contained and shielded from the environment. This could be done by making glass or cement blocks from the liquid waste. Some other liquid wastes at Sellafield are considered too dangerous to pour into the sea. These wastes are called the Highly Active Liquid wastes. Instead, these wastes are being converted into a solid form (they are "vitrified" to make glass blocks). This does not make these dangerous nuclear wastes safe, but it does mean that the waste can be properly managed and monitored to contain and shield it from the environment. This is the "least bad" option for existing nuclear waste, as it aims to prevent radioactivity from entering the food chain and causing cancers. At the same time, BNFL should be stopped from adding yet more liquid nuclear wastes to the tanks at Sellafield. This means closing BNFL’s ageing Magnox reactors and the Magnox reprocessing plant. Is it really feasible to stop the discharges? The Environment Agency has not properly considered the above "least bad" option for the nuclear wastes containing technetium-99. The Agency appears to have been misled by BNFL about the feasibility, costs and benefits of this option. The Environment Agency has given more weight to BNFL’s attempts to make the ageing Magnox programme economic than it has to protecting the environment. Two of the key issues are outlined below:
BNFL claims that vitrifying existing MAC (turning the existing liquid waste into glass blocks) would need a new plant, costing about £500 million and taking 8 to 12 years to build. According to BNFL, if (much cheaper) existing plant, which is currently being used to vitrify high level liquid wastes, were used to vitrify existing MAC as well, the tanks could not be emptied fast enough to meet the Nuclear Installations Inspectorate’s (NII) safety requirements. The option of vitrifying the existing MAC has therefore been dropped by the Environment Agency on cost grounds, in favour of pumping it into the sea (perhaps with some additional treatment after 2006). This is clearly not the best option for the environment. However, if BNFL stopped producing more high-level liquid waste and MAC, by stopping Magnox reprocessing, it would almost certainly be possible to vitrify all the existing liquid wastes and still meet the NII’s safety requirements. It is highly questionable whether the Environment Agency’s preferred option is really any cheaper anyway. The NII has already told BNFL that it is not vitrifying its high level liquid wastes quickly enough. As a result, there are already good safety reasons why BNFL should reduce or stop reprocessing, or build new vitrification plant. A recent serious accident, in which the liquid high level waste could have exploded whilst safety alarms were ignored, has added to these major concerns. This means that BNFL may have to spend the money for new vitrification plant anyway, if it wants to continue reprocessing. Or alternatively, reprocessing will have to stop, if BNFL decides it can’t afford to process the large volumes of dangerous liquid nuclear wastes that it produces. If reprocessing stopped now the smaller (existing) volume of liquid nuclear wastes (including the existing MAC) could probably be vitrified in existing plant without the existing tanks becoming any fuller – satisfying both the safety and environmental regulators. The Environment Agency is wrong to weaken its environmental requirements and to exclude the option of vitrifying existing MAC on the grounds of cost. Priority should be given to stopping the discharge of existing liquid wastes to sea, rather than allowing continued production of these wastes.
The Environment Agency has not considered any options that would reduce, suspend or stop future Magnox reprocessing. Instead it has assumed that Magnox reprocessing rates will more than double – even though this would significantly increase rather than decrease discharges from Sellafield, contrary to the OSPAR agreement. In fact the Agency is currently considering whether the continued operation of BNFL’s ageing Magnox reactors is justified, following a separate consultation on this. BNFL is legally required to show that the benefits of continuing to operate each Magnox reactor, and the associated Magnox reprocessing plant, outweigh the detriments (including the adverse effects of nuclear waste discharges on human health and the environment). Since BNFL cannot operate the Magnox programme economically without breaking environmental commitments like the OSPAR Strategy, this means the Magnox programme cannot be justified and should be shut down now. Cost-cutting on safety is also a key issue at BNFL’s Magnox reactors, which are all operating way past their original design lives. This is another reason to shut them now. Once the Magnox reactors are shut down there will still be a backlog of nuclear waste fuel from these reactors. Rather than reprocessing this nuclear waste fuel, causing further massive discharges, the options for storing it should be investigated. Dry above-ground, managed, monitored storage is the least-bad option for existing nuclear waste. This option has been identified as technically feasible for Magnox nuclear waste fuel by a number of detailed studies in the past. What can you do? Please email or write to the Environment Agency before the deadline of 5 March. Ask them to:
Note: Greenpeace also believes that reprocessing in Sellafield’s newer reprocessing plant (THORP) should be stopped, however this plant is not being considered in the current consultation, because it is not the main source of Tc-99. The Environment Agency’s website contains more information and you can also send an email to the consultation from there: http://www.environment-agency.gov.ukOr you can write to: Sellafield Review, Environment Agency PO Box 114, Penrith , Cumbria, CA11 9GN Tel: 01768-866666, Fax: 01768-892456 References: BNFL(1997), Statutory Environmental Monitoring Programmes, Quarter 2 1997, April-June. Strategy with Regard to Radioactive Substances, Ministerial Meeting of the OSPAR Commission, Sintra, Portugal, 22-23 July 1998. The Strategy promised that "by the year 2000…the [OSPAR] Commission will, for the whole maritime area, work towards achieving further substantial reductions or elimination of discharges, emissions and losses of radioactive substances." The OSPAR Strategy also promised "close to zero" concentrations of all radioactive substances in the marine environment by 2020 (excluding historic contamination). DETR Press Release, 23 July 1998. Environment Council, An Addendum to the BNFL Stakeholder Dialogue Discharges Working Group Interim Report of February 2000. Discharge levels at "nominal full throughputs". Sintra Statement, Ministerial Meeting of the OSPAR Commission, Sintra, Portugal, 22-23 July 1998. Contracting Parties are Belgium, Denmark, Finland, France, Germany, Iceland, Ireland, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, UK and the European Commission. FSA/SEPA(2000), Radioactivity in Food and the Environment, 1999, gives a level of 4700Bq/kg of Tc-99 in lobsters in the Sellafield coastal area. The intervention level is 1250Bq/kg. BNFL(2000), Submission to theUK Government’s Consultation on its Strategy for Radioactive Discharges, para A2iv. BNFL(2000), para C1iii. Greenpeace International (2001), BNFL’s Refusal to Implement the OSPAR Strategy with regard to Radioactive Substances, Submitted by Greenpeace International to the Meeting of the OSPAR Radioactive Substances Committee, Tromsų, 15-19 January 2001. BNFL(2000), para 15. BNFL(2000b), Annual Report and Accounts, September 2000. Environment Agency (2000), Explanatory Document to Assist Public Consultation on Proposals for the Future Regulation of Technetium-99 Discharges from British Nuclear Fuels PLC, Sellafield into the Irish Sea. EA(2000), Table A.2.1. EA(2000), para A2.37. For comparison, the Environment Agency’s preferred option (which would allow more waste to be produced and keep the existing discharge limit until 2006) is estimated to cost between £18 million and £185 million: EA(2000), Table A.2.1 (cost of MAC diversion plus TPP or abatement). HSE(2000), The storage of liquid high level waste at BNFL Sellafield, February 2000. The Observer, "Sellafield ignored blast alert", Sunday 11 February 2001. Environment Agency (2000), Explanatory Documents and Draft Authorisations to assist public consultation on applications by British Nuclear Fuels PLC to dispose of nuclear wastes from the Magnox power stations, May 2000. (Note: separate documents are available for each site). Greenpeace (2001), Wylfa nuclear power station and the National Assembly for Wales. Kempe, TF, Martin, A and Thorne, MC (1980), "Long-term storage of spent nuclear fuel", Work carried out for the Nuclear Waste Management Division, Department of the Environment, Associated Nuclear Services, ANS Report No.206, June 1980; DoE(1988), Commissioned Research on radioactive waste management 1987/88: Magnox fuel dry storage and direct disposal, Assessment of CEGB/SSEB reports, DoE report PECD7/9/400.
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