Assessment of Change in Shallow Land Burial Limits for Defense Transuranic Waste (Concentration Limit of 100 nCi/G)

摘要

There is an emerging consensus within the waste management technical community that the current concentration limit of 10 nCi/g for shallow land burial (SLB) of transuranic (TRU) waste is excessively restrictive. A concentration limit for SLB in the range of 100 to 1000 nCi/g is reasonable and justifiable based upon these reasons: Resultant increase in collective radiation dose (total population dose) would be very small, and the net detriment to public health would be negligible. Increasing the limit is cost-effective and could save hundreds of millions of dollars for the national economy over time. The hazard resulting from the increased SLB limit for TRU would be significantly less than that due to many naturally occurring mineral deposits and/or human activities. Expenditures directed toward health and safety conform to the economic law of diminishing returns: as the absolute expenditure increases, the marginal return decreases. Excessive restriction of the TRU concentration limit for SLB needlessly diverts limited resources (time, talent, and money) from other areas of health and safety where they might be more beneficially applied. Despite considerable effort, this study did not find any compelling technical argument to maintain the limit for TRU in SLB at 10 nCi/g. Subsequent to the initial preparation of this document, the US Department of Energy issued DOE Order 5820 which raises the administrative disposal limit for transuranic wastes from 10 nCi/g to 100 nCi/g. In addition, the US Nuclear Regulatory Commission has subsequently proposed and adopted a revised version of regulation 10 CFR 61 in which the disposal limit for shallow land burial of Category C (intruder protected) waste is set at 100 nCi/g. (ERA citation 08:031271)