Since that report was issued in August 2000, DOE has funded research and development on the three alternative processes, and significant progress has been made in ameliorating many of the technical uncertainties. DOE noted in its briefings to the committee that tests of all three treatment alternatives have demonstrated their ability to meet functional requirements. On that basis, and with the associated changes in the work programs of the three alternatives and their management, the DOE Technical Working Group (TWG)1 has produced downselection criteria. These were presented to the committee at its first meeting on 20-21 November 2000 (Harmon, 2000a, b), and represent the basis for this report.
DOE SELECTION CRITERIA AND GOALS
The TWG and its associated committees and consultants employed systematic and relatively transparent approaches for devising quantifiable evaluation criteria. Using information gathered from other DOE sites and other organizations, they began with twenty criteria and reduced them to the final eleven in an effort to eliminate redundancy and criteria unable to discriminate among the alternatives. The final set of criteria (see Box 1) was approved by the DOE Office of Environmental Management for use in making recommendations on process downselection.
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1 |
The TWG has the lead responsibility for developing recommendations on both research and development (R&D) direction and the bases for subsequent recommendations on process selection. This group, using input from a technical advisory team and the Tanks Focus Area (TFA), interacts with a representative of the DOE Office of Environmental Management responsible for the process development and recommendation for downselection. This representative recommends to the DOE Assistant Secretary for Environmental Management the final determination on the downselection outcome. |
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BOX 1 DOE Criteria for Process Selection at the Savannah River Site
SOURCE: Harmon, 2000a, 2000b (viewgraph on p. 20 entitled “Criteria Weights–Case A”), and H. Harmon, DOE, email communication, January 5, 2001. |
In recognition of some commonalties, the eleven criteria for process selection were grouped by the TWG under the set of six goals shown in Box 2. The criteria were used as a measurement for the effectiveness in reaching these goals.
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BOX 2 DOE Goals for Process Selection at SRS Goal 1: Meet schedule (Criterion 1) Goal 2: Minimize cost(Criteria 2 and 3) Goal 3: Minimize technical risk (Criteria 4 and 5) Goal 4: Minimize environmental safety and health impacts (Criteria 6 and 9) Goal 5: Minimize impact to interfaces(Criteria 7 and 8) Goal 6: Maximize process flexibility (Criteria 10 and 11) SOURCE: Harmon, 2000b, viewgraph on p. 14 entitled “Criteria Aligned by Goal” |
Other possible goals, such as ‘minimize tank space requirements' and ‘stakeholder acceptance,' were not included by DOE, because they were considered to be integral to the goals listed above or were not considered to be good discriminators among the alternatives.
The TWG employed a series of steps to develop and implement the proposed criteria. In particular, they used several groups of experts to carry out preliminary application of the criteria to evaluation of the three processing alternatives. This preliminary screening was intended to determine if the criteria were capable of distinguishing among the alternatives and to determine to what extent the outcome might depend on the relative weighting assigned to each of the criteria. In conducting this preliminary screening, each alternative was evaluated by the group of experts and assigned an integer score from 1 (worst score) to 5 (best score). The resulting scores were then normalized to generate ‘utility values'2 that ranged from 0 (worst) to 1 (best). Finally, each utility value was multiplied by a weighting factor ranging from 0.03 (low weight) to 0.14 (high weight); the highest weighting was given to technical risk (Criteria 4 and 5). Finally, a total score for each of the alternatives was calculated by summing the eleven individually weighted utility values.
Several preliminary scoring exercises (carried out by various advisory and management groups of the TWG) were reported at the November committee meeting. In all of the exercises the resulting total scores for the three alternative processes all fell within the range of 0.60 to 0.69; in one exercise the identical total score of 0.63 was calculated for all three alternative processes. The actual scoring and weightings were consensus values arrived at in review meetings among the experts following extensive discussion. This consensus represents the
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The utility value is computed by the formula ui= 0.25 (Ai-1), where Ai is the score from 1-5 for criterion i. The total score is then determined by multiplying each utility value by an assigned weighting factor (ki) and summing the weighted scores. Total Score = ∑ (ui kI) |
