Opinion ID: 407564
Heading Depth: 2
Heading Rank: 2

Heading: Consideration of Other Uncertainties

Text: 75 The NRDC seems to argue that Table S-3 masks uncertainties underlying waste-management activities other than permanent disposal. 138 It has not, however, indicated where those uncertainties lie or what values in the Table obscure them. Similarly, the Commission has responded to the NRDC by focusing primarily on the uncertainties surrounding the successful development of a permanent repository. 139 As a result, we face considerable difficulty reviewing this issue. 76 Table S-3 lists several gaseous and liquid radiological effluents along with low-level, high-level and transuranic solid wastes. 140 The gaseous and liquid effluent releases are expected to occur at the early stages of the waste-management process, before the wastes are solidified and prepared for permanent disposal. The staff reports supporting the Table S-3 Rules indicate that there is indeed uncertainty concerning the predictions of these releases. In contrast to its method of projecting releases from the solid waste stored in a permanent repository, however, it appears that the Commission used worst case estimates in determining Table S-3's values for gaseous and liquid releases. The Commission assumed, for example, that all of the tritium, krypton-85 and carbon-14 in spent fuel would be discharged into the environment during reprocessing. 141 The Commission also seems to have used equally conservative assumptions in determining Table S-3's values for releases of iodine-129, iodine-131 and other radioactive gases. 142 One issue before us, therefore, is whether the Commission violated NEPA in treating these uncertainties in this manner, rather than by representing uncertainty itself in the Table. We hold that it did not. 77 As we have emphasized above, NEPA requires an agency to consider the environmental risks of a proposed action in a manner that allows the existence of such risks to influence the agency's decision to take the action. 143 An agency can do this by having the appropriate decisionmakers consider all that is known and unknown about the risks before deciding whether to take an action. Or, it can organize its decisionmaking process in such a manner that the appropriate decisionmakers consider only the upper bound of reasonably foreseeable environmental costs. If, after considering that level of environmental damage, the decisionmakers conclude that the proposed action is worth its societal costs, full account will have been taken of the action's environmental impact. Similarly, if the upper bounds of environmental risks are disclosed in an EIS, Congress, the public, and any interested agency can effectively assess for themselves whether the agency has proposed an action that is not worth its environmental costs. Either method of considering and disclosing uncertainties surrounding an environmental effect is acceptable under NEPA. 144 Thus, to the extent that the Commission has listed the upper bound of reasonably foreseeable gaseous and liquid effluent releases in Table S-3, we hold that it has complied with NEPA. 78 It is impossible for this court to determine whether there are other numerical values in Table S-3 that mask uncertainties without using such conservative heuristic devices as a worst-case scenario. We expect, however, that the Commission's consideration of uncertainties underlying the zero-release assumption will encompass any significant uncertainties underlying other values in the Table. 145 79