A review and evaluation of the Draft EPA standard (40 CFR 191)

The Environmental Protection Agency's proposed rule for the management and disposal of high-level waste (Draft Standard, 40 CFR 191), was reviewed and analyzed using the risk assessment methodology developed at Sandia National Laboratories. The methodology was exercised on hypothetical repository systems in basalt, bedded salt, and tuff. Among the issues addressed were achievability, release limits, uncertainty, and compliance. The proposed release limits were also analyzed in terms of their relationship to the health effects. The uncertainty in the input parameters of the deterministic models was taken into account in calculating releases to the accessible environment. Extentions to an existing compliance-assessment methodolog are suggested that would allow one to incorporate the uncertainty associated with the frequency of occurrence of scenarios. The results indicate that, in general, the standards are achievable and the release limits are sufficiently conservative