RWMAC report on MoD radioactive waste practices

ANNEX 8
ESKMEALS AND KIRKCUDBRIGHT

1. The last RWMAC report on defence radioactive wastes described the layout of the Eskmeals land firing range, and its activities, in some detail. The most recent programme of improvements to the VJ battery and butt ("the battery"), where firing of depleted uranium projectiles took place, which had been completed by the time of the last report, was also described. As will be clear from the coverage of Eskmeals in section 8 of the main report, the battery is presently mothballed. The issues which RWMAC believes are relevant to MoD's decision about the site's future are set out in section 8 and it is not necessary to repeat them here.

2. Nevertheless, RWMAC visited Eskmeals in July 2000 and held valuable discussions with MoD staff. The meeting also covered the Kirkcudbright land range. The information that emerged from the visit, covering both sites, and RWMAC's impressions of the radioactive waste management and radiological protection issues with which the two sites deal, are the subject of this Annex.

Status and management of the sites

3. The Eskmeals site is part of the Defence Test and Evaluation Organisation (DTEO) which, in turn, is part of the Defence Evaluation Research Agency (DERA). Together with a few other sites where test firing is carried out (although these do not deal with radioactive wastes), it belongs to part of DTEO known as "Test & Evaluation - Ranges", or informally as "Land Ranges". The present situation appears to be that Eskmeals is likely to be included in the planned privatisation of parts of DERA. The site will remain in MoD ownership and will be leased to the privatised DERA. It is understood that the Kirkcudbright site is owned by the Army and is used as an infantry training area.

4. The Eskmeals site has a MoD top management structure, about 25 per cent of the total workforce, but, since 1987, most of the site staff have been supplied by the private sector. RWMAC's observation of MoD's caretaker arrangements for the battery did not suggest that accounting for safety posed significant difficulties. Overall, however, the site arrangements were said to make safety accountability a "complex problem".

Site operations

5. Both sites are used for proof firing of a wide range of calibre weapons by the UK's armed services. The only activity at either site which has radioactive waste management implications is the test firing of projectiles made up in part of depleted uranium and related alloys. These projectiles are "solid rounds" (not containing explosives). As well as "soft targets" (used, for example, to test accuracy, behaviour of the projectile in flight, etc.), "hard targets" are used for testing the effect of depleted uranium projectiles against conventional and experimental armour plating, also including depleted uranium.

6. Eskmeals was used for short range firing in the battery and its associated butt. Kirkcudbright is used for distance firing (1-2 miles) through soft targets into the Solway Firth. The essential difference is that at Eskmeals the projectile is designed to destruct on hitting the hard target, with the radioactive debris contained within the butt. At Kirkcudbright, the depleted uranium projectile is intended to be "placed" intact in the Solway Firth.

Radiological protection

7. At Eskmeals, a well-defined protocol is in place for workers required to enter the VJ butt after test firing. Before they can do so, allowance is made for a cooling period during which cooling fans with three layers of air filtration are in operation. Members of the butt entry party are required to wear full protective clothing with pureflow hoods and carry personal air samplers.

8. Before any workers are allowed to enter the butt without full protective clothing, decontamination procedures are first carried out. The butt must be officially declared free of mobile DU material.

9. All butt working parties undergo urine analysis and whole body monitoring is also available. RWMAC understands that a positive result for internal DU exposure has never been recorded. MoD has maintained a dedicated health physics team at Eskmeals since cessation of DU projectile testing in 1995.

10. In RWMAC's view, these precautions, taken against the possible exposure of workers, are robust.

11. As RWMAC's previous report made clear, the butt is (to the greatest practical extent consistent with its function) enclosed in order to prevent uncontrolled dispersal of material after firing. RWMAC understands that MoD has carried out some work in the past on particle size in order to be able to assess both the potential for particle movement beyond the butt and risk of ingestion by workers. This work was completed in 1983, however, and has not, to the Committee's knowledge, been reviewed.

Ground contamination

12. Against "design" operations at either site, the extent of contamination is complicated by two factors. First, the projectile can break up in the gun barrel, causing it to "splay out" short of the battery butt or the Solway Firth causing land contamination; second, depleted uranium (whether as "placed", lost or destructed rounds) can degrade in the soil or sea bed environment to uranium oxides.

13. At Eskmeals, the contamination is mainly found within the radiologically controlled area of the VJ battery and butt and, to a small extent, around it. Potentially, at least, it may be present elsewhere on the site. Health physics monitoring is carried out within the battery and the surrounding controlled area. Soil samples (six cores per m²) are regularly taken. The health physics staff at Eskmeals consider that this identified ground contamination is not likely to migrate.

14. At Kirkcudbright, contamination occurs adjacent to the battery, on other parts of the site particularly near the cliffs, and in the Solway Firth sea bed. Land contamination is thought to be more discrete than at Eskmeals (possibly because of the absence of hard targets), although it is possible that some projectiles are embedded deep in the ground. MoD has indicated that a detailed land survey will shortly be undertaken with the aim of identifying the extent of ground contamination at the site. Projectiles are also known to be on or, more likely, deeply embedded in the sea bed. On rare occasions, they have been recovered by dredgers.

15. Partly, but not solely, because both sites will, in due course, be subject to remediation measures to permit their redevelopment, RWMAC believes it is important that MoD has comprehensive knowledge of the nature of the ground contamination. To a major extent, this can be obtained through site surveys. However, it would also be sensible to look into the precise composition of the DU projectiles (which are believed to be of US origin) in order to assist the process of characterising the radioactive contamination present on the two sites. In the light of press reports that DU projectiles may contain small amounts of plutonium and uranium-236, RWMAC believes that MoD needs to address the potential for radioactive contamination arising from the projectile testing programme after confirming the composition of the DU munitions used. A similar view is taken in relation to environmental monitoring carried out at the sites (see paragraph 8.3 of the main report).

16. The results of any such investigations should be made public. If necessary, the findings of the environmental assessment of Eskmeals carried out in 1995 (see paragraph 20, below) should be reviewed.

Environmental monitoring

17. The environmental monitoring programmes at both Eskmeals and Kirkcudbright are endorsed by EA and SEPA respectively. This is, of course, separate from the required monitoring of the controlled area, established, for radiological protection purposes around the Eskmeals VJ battery and butt. General site monitoring is carried out using Geological Survey Instrumentation and contaminated areas are pegged out for exploratory digging. Sea bed monitoring at Kirkcudbright has not produced evidence of radioactive contamination. Interpretation of results generally is, however, made difficult by the existence of natural uranium seams, particularly at Kirkcudbright.

18. There are 19 environmental monitoring points on the Eskmeals site and seven high volume air samplers are in continuous operation off-site. Nineteen environmental monitoring points are believed to be in operation at Kirkcudbright. There is detectable, but not significant, contamination from depleted uranium in the general environment of both sites.

19. DERA collects samples from both sites for monitoring by DRPS. This covers air, groundwater, drinking water, agricultural produce and animal droppings. Kirkcudbright monitoring also takes in fish, shellfish (including offshore mussel beds) and seaweed. The mussel beds could potentially be affected by the outflow of contaminated groundwater, but nothing has been detected to date. For marine monitoring at Eskmeals, only shellfish are analysed, but the off-shore mussel beds are monitored. DRPS produce annual monitoring reports for both sites which are widely distributed.

20. A baseline for contamination at Eskmeals has, in broad terms, been established by an environmental assessment report produced for MoD by NNC Ltd and W. S. Atkins Consultants Limited in January 1995. This could be significant in terms of establishing liability for possible future decommissioning at Eskmeals since test firing of depleted uranium ceased later that year.

21. In RWMAC's view, these arrangements appear comprehensive and effective. A slight cause for concern is that the publicly-available DRPS monitoring reports do not include information for the most heavily contaminated area of either site - the Eskmeals controlled area. RWMAC understands that SEPA has voiced concerns that contamination should be contained within the Kirkcudbright site, and, where this occurs, it should be physically marked out.

Waste management and regulation

22. Because test firing is suspended, there is almost no active radioactive waste management at Eskmeals. Residual arisings are from malfunctioning monitoring equipment, etc. The only waste now stored on site is solid LLW, about three cubic metres, in metal drums.

23. During the visit, RWMAC was provided with more information on the historic solid waste streams than was included in the last report. Since the information would be relevant if firing was to resume, a more complete account is given here.

24. These historic waste streams consisted of destructed depleted uranium projectiles and target armour, associated debris, and a variety of soft waste - filters, contaminated overalls, etc. This was dealt with in three ways :

- where depleted uranium was lodged in armour plate, the surrounding area ("coupon") was cut out. Up to 10 coupons could be sealed within a steel box (pallet), mixed with contaminated debris and cement, and topped with clean cement. This was the packaging accepted for disposal at Drigg;

- soft LLW was drummed for disposal at Drigg;

- other armour plate (below activity levels for classification as radioactive waste under RSA93) was stored on site pending EA agreement for clearance and recycling via bona-fide smelting operators.

25. A liquid waste stream arose from decontamination operations within the VJ butt where high pressure hosing was used to reduce suspension in air, clean the target and concentrate contamination. The liquid waste was initially collected in catch pots where the larger depleted uranium particles were removed. The liquids were then transferred to re-settlement tanks for monitoring, but were not held back unless they contained a significant amount of sludge. If so, they were pumped into a holding tank. Sludge in the tanks was monitored, spaded into drums, mixed with cement and sent to Drigg. The liquid wastes were subsequently disposed of by pipeline into the dunes. There was no provision for decay. Sampling within the dunes area was by means of two boreholes below the discharge points. Sampling and assaying was also carried out at a well (which does not provide potable water) two kilometres south of the beach.

26. The EA "letter of approval" for the disposal of radioactive waste is unchanged since the last visit and solid and liquid disposals have always been well within limits. There is no authorisation for gaseous waste. EA Noting Letters (which are pseudo-RSA93 registrations) cover calibration sources. All MoD practices on the site which involve radioactive materials are covered by the provisions of the relevant Joint Service Publication.

Local involvement

27. There appears to be limited public interest among the nearby community other than attendance at an annual meeting to launch the environmental monitoring reports. There is no Local Liaison Committee, but it is understood that the public are able to visit the site by appointment.

28. The local authority is Copeland BC in whose area the Sellafield and Drigg nuclear sites are also located.

RWMAC observations

29. The Committee sees no reason to depart from the view expressed in its last report that considerable care is taken at the Eskmeals site with regard to the management of radioactive materials and wastes. Equally, the standards of radiological protection applied are high. Although the site has evidently not been brought within MoD's LQA system (see paragraph 8.12 of the main report), local knowledge about the extent of contamination is said to be thorough.

30. Environmental monitoring appears to be comprehensive at both Eskmeals and Kirkcudbright. The one proviso is that RWMAC believes DERA should make public (through release of the DRPS report) the information it holds about the degree of contamination within the VJ battery controlled area.

31. The factual information provided to the Committee about Kirkcudbright is recorded here, but RWMAC Members did not visit the site and no further comment is, therefore, possible.