Bellona’ s response regarding a possible Tc-99 moratorium

Publish date: January 15, 2003


Mr. Michael Meacher, Environmental minister
Department for Environment, Food & Rural Affairs
Nobel House
17 Smith Square


The Bellona Foundations Response to the Secretary of State for the Environment, regulation of Tc-99

1. Summary

This document sets out the response of the Bellona Foundation to the State’s Decision Document concerning the Environmental Agency’s proposed decision for the future regulation of technetium-99 (Tc-99) discharges from the BNFL Sellafield site into the Irish Sea. The document first describes some of the background for the liquid discharges of Tc-99. It then describes Bellona’s position according to the Ministers suggestion to introduce a moratorium on Tc-99 discharges. Bellona argues that:

* A moratorium on the Tc-99 discharges should be introduced at once, and not be delayed by a new time-consuming review. Information from the Environment Agency’s recent reviews of Tc-99 options is already sufficient to assess the consequences, cost and benefits of such a moratorium.

* It must be up to the company involved, and the regulators to choose which technology which in the best way meets the challenges arising from such a moratorium.

* Ministers must make an exception from the NIREX requirements, and make it possible to conduct a TPP-plant-trail. This exception must be made to make it possible for the regulators and the company to choose between the different abatement technologies. A full review of the NIREX requirements may only be needed if the TPP-process proves to be successful.

* Welcomes the fact that ministers support the Environmental Agency’s proposed decision to introduce MAC diversion no later than March 2003.

2. Background
The oldest, still operating reprocessing plant at Sellafield is B205. This plant was put into operation in 1964 and reprocesses Magnox fuel from the oldest reactors in Great Britain. Magnox fuel is made from metallic uranium. The second reprocessing plant at Sellafield, THORP, commenced operation in 1994. THORP reprocesses regular spent reactor fuel made from uranium oxide. The total Tc-99 discharge outlet from these two plants amounts to 70 –90 TBq of per year. Reprocessing of Magnox fuel in the oldest reprocessing plant (B205) is by far the greatest source of Tc-99 discharges. Depending on the fuel burn-up, reprocessing of Magnox fuel generates between 20 TBq-30TBq of Tc-99 annually. In addition, between 50 TBq-60TBq of Tc-99 from the historic waste is discharged annually. The historic waste is stored on the Sellafield site and originates from the B205 plant. For comparison, the annual discharge of liquid radioactive waste from THORP is about 1TBq of Tc-99.

The reason for these discrepancies is that THORP has a technology that separates more than 99 per cent of the Tc-99 waste, which is vitrified along with other high-active waste, and subsequently stored onshore. In the much older B205 plant, only 30 per cent of the Tc-99 waste is handled along with the high-active waste. The remaining Tc-99 is handled together with the medium-active (MAC) liquid waste, which following purification is discharged into the sea.

2.1 The opening of EARP
The opening of the Enhanced Actinide Removal Plant (EARP) in 1994 led to a dramatic increase in Tc-99 discharges. Though EARP purifies the alpha-emitting radionuclides, it does not extract the Tc-99, which is a beta-emitting radionuclide. In 1995 BNFL discharged as much as 190TBq of Tc-99. At that point the discharge permit was set to 200TBq/year. In January 2000 the authorities restricted the permit to 90TBq annually.

In 2012 BNFL is going to close down the B205. By that time, all the produced Magnox fuel must be reprocessed. Three years later the discharges of Tc-99 will cease, and the only remaining discharges will come from THORP. Unless new purification technologies are implemented, the total Tc-99 discharge from B205, including the discharges of historic waste, will add up to 590TBq.

For the last few years the British Environmental Agency (EA) has examined all BNFL’s discharge permits for discharges to sea, air and soil. As part of this project the EA made an evaluation on how they are going to regulate discharges of Tc-99 in the future.

In September 2001 the EA handed over its report to the Department of the Environment, Food and Rural Affairs (DEFRA) for review. EA has in this report to a large extent relented to BNFL’s arguments. For instance, the EA recommends that BNFL is given a permit to discharge what is left of the historic waste. Consequently, an additional 2,000 cubic metres of MAC, and 200TBq of Tc-99 will be discharged into the sea. Furthermore, the EA recommends that BNFL’s current discharge permit, allowing 90 TBq of Tc-99 to be discharged annually, is maintained until 2006. The EA reckons that BNFL must have developed the new TPP purification technology at that point, which allows for a retrenchment in the discharge permit to 10TBq/year. However, the discharge limit will still be three times as high as the permit in early 1994.

With reference to future MAC arising, resulting from the reprocessing in B205, the EA require BNFL to re-route this waste to the plant handling highly active liquid waste (B215) for future vitrification. The EA recommends the implementation of such a treatment by March 31st 2003

3. Environmental and economic consequences
Technetium-99 spreads relatively easily into the environment. The Norwegian Radiation Protection Authority (NRPA) estimate that discharges from Sellafield take approximately 2.5 years to reach the Norwegian coast.

Thus, relatively soon after the increase in discharges, there were increased values of Tc-99 along the entire Norwegian coast. As early as November 1996, Tc-99 had reached the coastline outside Rogaland on the west coast of Norway, and by December 1997, the substance had reached the coastline outside Troms in the northern part of Norway.

Samples prepared by the NRPA in 2000 show traces of Tc-99 as far away as Svalbard. The concentrations ranged from 0.1 – 7 Bq/m3. The highest levels were observed in the North Sea.

Bellona has previously documented a maximum concentration at a level of 33 Bq/kg Tc-99 (wet weight) in lobster caught off the southern coast of Norway in 2001. Furthermore, in 1998, the Norwegian Radiation Protection Authority reported a maximum concentration of Tc-99 in lobster mounting to 42 Bq/kg (wet weight).

Another issue is the high level of Tc-99 in seaweed, resulting from the increased discharges of this isotope from Sellafield over the last few years. Up to 510 Bq/kg (dry weight) Tc-99 was observed in seaweed off the southern coast of Norway in 1999. Although the Norwegian waters, fish and other seafood in general can be considered clean, the seaweed and lobsters can not. This clearly demonstrates the actual environmental problems caused by Sellafield, and there should be no doubt that the source of Tc-99 must cease.

Beside the environmental concerns, Norwegian business interests are threatened by the discharges. Norwegian enterprises basing their activity on raw materials such as seaweed, sea tangle, lobsters and related organisms experience a loss of both national and international market share. Norwegian aquaculture sell high-quality products of “arctic quality” harvested in the cold and pure waters in the northern areas. Obviously, international customers react strongly to buying polluted commodities, which also are the most expensive on the market. The value of being able to market raw materials as “clean” has now been lost. Norwegian enterprises experience that unique raw materials no longer satisfy the quality demands established by the international market. Most likely, the value of these commodities will be further reduced if Sellafield continues to handle Tc-99 with its current technology.

4 The Ministers’ Decision of December 2002
The secretaries of the Department of Health and Department for Environment, Food and Rural Affairs reviewed the Environment Agency’s decision and announced their ministerial decision on 11 December 2002 (DEFRA and DoH, 2002), with a proposed direction to the Agency.

The Ministers’ decision document states that the Agency’s Tc-99 Decision Document has “been admirably detailed and thorough” and that “Ministers recognise that the Agency has had to deal with a difficult and complex review and consider that it has done so in way which is objective and which has balanced the conflicting pressures so as to produce a fair and reasonable outcome”.
Ministers propose that the Agency should now be directed “to invite representations, consider and report back in writing to the Ministers on whether it would be possible to impose a moratorium on the discharge of Tc-99 pending the introduction of TPP abatement technology”.

4.1 The proposed direction specifies that:
The Agency shall invite representations from interested parties and consider whether it would be possible to impose a moratorium on the discharge of technetium-99 from the Sellafield site pending the introduction of TPP abatement technology.

In considering the possibility of such a moratorium, the Agency shall consider the possible options for the storage of MAC, in particular:

(a) the possibility of refurbishment of B211 with a view to extending the use of that building;

(b) the possibility of storing MAC in other buildings, such as B212 and B213, if the tanks in those buildings are not already irreversibly committed; and

(c) the possibility of further concentrating MAC so as to reduce the volume that would need to be stored.

5. Bellona’s opinions on the proposals

5.1 Introduce the moratorium at once
In general, Bellona is happy that the ministers will look into the possibilities for a moratorium on Tc-99 discharges, although Bellona will advocate the introduction of the moratorium at once. Bellona argues that there is no sensible reason for delaying the moratorium decision. The more time the Ministers spend on considering the different kinds of abatement technologies, the more Tc-99 will be discharged to the Irish Sea, contaminating the marine environment and neighbouring countries’ coastlines. The moratorium must be placed on Tc-99 discharges from B205 and the historic waste in B211 storage tanks. This will make it feasible to reduce Tc-99 discharge limits to the limits prior to commencing of EARP in 1994.

The costs associated with the Tc-99 Authorisation’s review have already been significant. Information from the Environment Agency reviews the different ways to treat Tc-99 is already sufficient to assess the consequences, costs and benefits of the moratorium. Further reviews will only cost valuable time and recourses, which the Agency, BNFL and the NII should spend on finding the best way to implement the moratorium.

Because of the MAC-diversion scheme, there will not be more accumulated Tc-99 waste after March 2003. Therefore a moratorium will not generate more liquid waste stored onsite, and it will not be contrary to the recommendations from the Health and Safety Executive (HSE).

Bellona is fully aware of the HSE’s concerns about the age and condition of the building and the tanks in which MAC is currently stored. Besides, it must be up to the regulators and the company involved to find the most secure solution to this challenge.

5.2 Abatement technologies
There exist several technologies that can remove Tc-99 from discharges. Bellona’s general view is that it must be up to the company involved, and the regulators to choose which technology meets the requirements from the ministers. But the ministers have responsibility to make it possible for the regulators to make a decision about the preferable solution.

Bellona’s position is that historic MAC should be treated the same way as new MAC. It should be vitrified. However, BNFL argues that the high concentrations of iron and sodium in the historic waste make vitrification inappropriate for treatment at B215. The high content of iron and sodium is a result of the repeated evaporation processes that the historic waste has been submitted to (for minimising the volume of MAC). However, this problem may be solved by gradually blending this waste into the continuous stream of HAC diverted to vitrification. The EA has considered such an option, but claims that this method would require at least ten years before B211 would be drained of MAC. Considering the fact that at the current pace it may take five to six years to empty the tanks, this is not a sustainable argument against vitrification.

Bellona recognises that the Tetraphenylphosphonium bromide (TPP) technology is the most developed for Tc-99 treatment. According to BNFL, all the laboratory scale development work has been completed for TPP. The next step is a plant trail. The regulators are currently withholding permission for a TPP plant trail because of concerns about the solid waste produced and its lack of compatibility with NIREX requirements. Regulators are also concerned about TPP toxicity levels.

The solid waste compatibility issue is essentially one of UK national waste management policy to be resolved between regulators and government departments. Further research of this kind will not resolve the issue of the acceptability of the Tc-99 bearing waste to a future NIREX repository.

Before a new waste form can be produced the Regulators require that NIREX issue a Letter of Comfort (LoC) to confirm that it would be acceptable in their generic model of a future repository.

NIREX are presently unable to issue a LoC. This issue is essentially one of UK national waste management policy to be resolved between regulators and government departments. Bellona’s position is that the ministers should make it possible for BNFL to do a plant trail with TPP. This can be done by implementing an exception from the NIREX requirements for the small amount of waste resulting from at plant-trail. A full review of the NIREX requirements may only be needed if the TPP-process proves to be successful

Bellona is well aware of the toxicity problems connected with TPP. To minimise environmental consequences, such a plant-trail has to be well supervised by the regulators. But without testing the technology the regulators wont even be able to figure out which abatement technology is most satisfactory to meet challenges imposed by a possible moratorium, how much TPP such an abatement technology would release and how much Tc-99 it would filter.

Nils Bøhmer
Nuclear Physicists

Erik Martiniussen