Radiological criteria for the remediation of sites for spent fuel and radioactive waste storage in the Russian Northwest

Abstract

In the 1960s, two technical bases of the Northern Fleet were created in Northwest Russia, at Andreeva Bay in the Kola Peninsula and Gremikha village on the coast of the Barents Sea. They maintained nuclear submarines, performing receipt and storage of radioactive waste and spent nuclear fuel, and are now designated sites of temporary storage (STSs). An analysis of the radiation situation at these sites demonstrates that substantial long-term remediation work will be required after the removal of the waste and spent nuclear fuel. Regulatory guidance is under development to support this work. Having in mind modern approaches to guaranteeing radiation safety, the primary regulatory focus is on a justification of dose constraints for determining acceptable residual contamination which might lead to exposure to workers and the public. For these sites, four principal options for remediation have been considered-renovation, conversion, conservation and liquidation. This paper describes a system of recommended dose constraints and derived control levels formulated for each option. The unconditional guarantee of long-term radioecological protection provides the basis for criteria development. Non-exceedance of these dose constraints and control levels implies compliance with radiological protection objectives related to the residual contamination. Dose reduction below proposed dose constraint values must also be carried out according to the optimisation principle. The developed criteria relate to the condition of the facilities and the STS areas after the termination of remediation activities. The proposed criteria for renovation, conversion, conservation and liquidation are entirely within the dose limits adopted in Russia for the management of man-made radiation sources, and are consistent with ICRP recommendations and national practice in other countries. The proposed criteria for STS remediation and new industrial (non-radiation-hazardous) facilities and buildings on the remedied sites had, until now, no analogues in the Russian system of regulation of radiation-hygienic standardisation. The proposals made here may serve as a basis for corresponding standards at other sites.

Protection of the environment in existing exposure situations

“…The contamination levels are dominated by Sr-90 and Cs-137, and the levels vary significantly across the site (Shandala and Kiselev, 2014). Table 1 presents the extant regulatory dose constraints for people for each remediation option proposed, taken from Shandala et al (2008), together with concentrations of Sr-90 and Cs-137 in soil that correspond to the dose constraints applied. It is recognised that reference levels could be considered in this context, but given that the context involves rehabilitation of the previously occupied land as described in Chapter 1, it could also be considered as a planned situation.…”

“…Andreeva Bay is a site for the temporary storage (STS) of spent nuclear fuel and radioactive waste. Despite its current use, it is a major nuclear legacy site, which is also being remediated in the north-west of Russia (Shandala et al., 2008). As part of a regulatory cooperation programme between the Federal Medical and Biological Agency of Russia and the Norwegian Radiation Protection Authority, a project has been set up to investigate the possible impact of radioactive contamination on representative animals and plants in the STS area.…”

“…As part of a regulatory cooperation programme between the Federal Medical and Biological Agency of Russia and the Norwegian Radiation Protection Authority, a project has been set up to investigate the possible impact of radioactive contamination on representative animals and plants in the STS area. The objective was to determine whether the criteria, based primarily on the protection of humans, set out in Shandala et al. (2008) for the range of proposed remediation options would be sufficient to meet protection objectives for the environment as represented by ICRP’s DCRLs.…”

“…Table 1 presents the extant regulatory dose constraints for people for each remediation option proposed, taken from Shandala et al. (2008), together with concentrations of Sr-90 and Cs-137 in soil that correspond to the dose constraints applied.…”

“…Several factors should also be considered more widely when interpreting the above results in the context of existing exposure situations. Firstly, the regulatory dose constraints were set at a time when there were no Russian documents to regulate issues of remediation of radioactively contaminated areas relating to existing exposure situations (Shandala et al., 2008); it should be noted that all the constraints are within respective dose limits. Secondly, the exposures to the fauna and flora at the site are likely to continue for long periods of time, covering the life span of several, or more, generations of the relevant species, and we are still learning about the consequences of long-term transgenerational exposures of wildlife.…”