Evaluation of Criteria for Selecting a Salt Processing Alternative for High-Level Waste at the Savannah River Site: Interim Report (2001)

informed judgement of these experts. The TWG program plans to reevaluate quarterly the scoring of the alternative processes to take into account the relative progress in the R&D efforts for each alternative. A final downselection decision to one process is scheduled for June 2001.

Criterion 1: Schedule Risk. The time frame for completion of the cleanup activity could readily be modified by subsequent funding or policy decisions or by environmental issues. Hence, while the criterion is generally useful in broad terms, it may not be a significant discriminator among the processes. It might be preferable to employ this criteria on a ‘go/no go' basis, in which it would have zero weight unless the calculated risk exceeded the inherent uncertainty.

Criterion 2: Project Cost Reduction Potential. Cost is an important consideration in any project of this magnitude. The costs assigned to the process are likely to be governed largely by the cost of major new facilities, and DOE has carried out extensive cost estimates. These initial estimates did indicate differences between the three processes, but the uncertainty in these estimates is sufficiently large that the projected costs for the three alternatives may be essentially equivalent.³ Cost reduction would result from divergence from the estimates, so if these have been carried out consistently (i.e., with the same level of conservatism), it is unlikely that the criterion will discriminate among the alternatives. At this early stage, cost estimates are not very accurate, and from a policy standpoint there may be a difference between capital costs and operating costs that makes the current estimate of life cycle costs inadequate as a factor for decision making.

Criterion 3: Life-Cycle Costs Through Decontamination and Decommissioning. The federal budgeting procedure takes place on an annual basis and does not ordinarily include life-cycle costs. In addition, funding from more than one DOE Environmental Management office complicates the financial aspects of the cleanup. Consequently, while life-cycle cost is an important issue, the high uncertainties in DOE cost estimates may limit its value in decision making unless the project is privatized.

Criterion 4: Technical Maturity. This criterion appears to provide reasonable input for the downselection procedure, since the major uncertainties identified by the previous committee (National Research Council, 2000) were in areas of science and technology.

Criterion 5: Implementation Confidence. This criterion evaluates the extent to which a given technology has been demonstrated or deployed at large scale, with higher scores assigned when previously used for processing radioactive materials or used within the DOE complex. This does not appear to be independent of Criterion 4, and if given too large a weighting, could result in double counting.

Criterion 6: Minimize Environmental Impacts. Any process selected for implementation would need to gain the necessary regulatory approval, which will be a clear “yes/no” decision. While it is an appropriate goal for each of the alternative processes to minimize radioactive and chemical emissions and generation of secondary waste, the process to be selected will either meet regulatory approval or it will not. The minimization of waste streams is closely tied to project