Under state law and administrative code (WAC197-11-600 and -620), the City may only require an SEIS based upon:
- actual data showing substantial changes to a proposal such that the proposal is likely to have significant additional adverse environmental impacts; and/or
- new factual information indicating a proposal's probable newly discovered significant adverse environmental impacts.
The actual data showing substantial changes, and/or the new factual information about newly discovered impacts must be completely new, and the newly discovered or identified environmental impacts must not be within the range of alternatives and impacts already analyzed in the existing Final Environmental Impact Statement (FEIS). Criticism of the existing FEIS, or speculation about what PSE may do in the future does not constitute completely new factual information, or completely new probable significant adverse impacts.
The FEIS, which was not appealed, addressed the safety of plant operations. Washington State law is clear that an EIS is not a catalog of every conceivable effect. "An environmental impact statement is adequate under the rule of reason if it presents a reasonably thorough discussion of the significant aspects of the probable environmental consequences of the proposed development. An environmental impact statement is not a compendium of every conceivable effect or alternative to a proposed project but is, simply, an aid to the decision-making process. The environmental impact statement need include only information sufficiently beneficial to the decision-making process to justify the cost of its inclusion. Impacts or alternatives having an insufficient causal relationship, likelihood, or reliability to influence decision makers are 'remote' or 'speculative' and may be excluded from the impact statement." Preserve our Islands et al., Appellants, v. The Shorelines Hearings Board, et al, 133 Wn. App. 503 (2006).