The Council on Environmental Quality (CEQ) recently issued a proposed memorandum, 48 Fed. Reg. 36486 (1983), for federal agencies concerning the implementation of CEQ's "worst case anslysis" regulation, 40 C.F.R. 1502.22, ELR REG. 46023, promulgated under the National Environmental Policy Act (NEPA). The regulation provides for a "worst case" analysis in environmental impact statements (EISs) in rare but important circumstances. The basic requirements of the rule are simple—if an agency would like to do something which may have severe environmental consequences and it does not know what the effects will be and either cannot find out (i.e. it is beyond the state of the art), or is unwilling to pay the cost of finding out, it must at least determine and take a look at the worst that might happen before it plunges ahead. The proposed guidance memorandum would create an "initial threshold" of "reasonably foreseeable impacts or effects" before a "worst case" analysis would be required. "Potential adverse impacts" with an extremely low probability of occurrence would not be subject to analysis because they do not meet the threshold.

At first blush, any proposal calling for reasonable foreseeability is compelling. For several reasons, however, the proposal is not a reasonable interpretation of the worst case rule and is, indeed, downright harmful. It would not only gut the purpose of the rule, but is contrary to existing case law and previous CEQ interpretation of the rule, and to judicial interpretations of NEPA prior to the rule's promulgation.