Washington’s State Environmental Policy Act (SEPA) requires that prior to any decision with a “probable significant environmental impact,” the public decision maker publish an environmental impact statement (EIS). When any governmental permit is requested (with narrow exceptions), the government must first make a threshold determination as to whether the proposal does have a probable significant environmental impact. If not, or if that impact can be mitigated to non-significance, the proposal can proceed based on a determination of non-significance (DNS) or a mitigated determination of non-significance (MDNS). A threshold determination that an EIS is required, on the other hand, can literally add years to the permitting process and hundreds of thousands of dollars to the cost of entitlements.

So, it is of interest to all parties who routinely need permits from state or local government that on May 27 the Department of Ecology released draft guidance for addressing greenhouse gas emissions under SEPA. Ecology will take comments on the draft guidance until June 25, 2010.

Sources of greenhouse gases that would require SEPA review include not only the usual suspects – electricity generating plants, manufacturing facilities, and fuel combustion at industrial sites – but also residential and commercial development. Emissions to be considered include not just emissions under the direct control of the project proponent (Scope One emissions), but also emissions from purchased energy (Scope Two emissions), and emissions that will be produced as a consequence of the proposal, such as transportation demand created by the project (Scope Three emissions).

The draft guidance encourages the SEPA responsible official (the government person who makes the threshold determination of EIS/no-EIS) to consider mitigation of greenhouse gas emissions that could be imposed under SEPA. As a practical matter, that will mean that transportation demand management will now become a standard part of SEPA review, whether or not there is a congestion issue in the area.

The draft guidance also points out that SEPA requires that cumulative impacts be addressed. Of course the actual greenhouse gas emissions of any particular project may be barely measurable, but the cumulative effect of all those barely measurable emissions is huge. The draft guidance leaves for local jurisdictions to decide at what emissions become “significant” when viewed on a cumulative basis.

Finally, the draft guidance requires that the public official consider the vulnerability of the proposal itself to the impacts of climate change. If sea levels rise, what will that mean to the project? If future storms are more severe, how will that change the impacts of the proposal?

This draft guidance is hardly a surprise. The Council on Environmental Quality (CEQ) issued draft NEPA guidance in March. But SEPA applies to a far greater number of governmental decisions than NEPA applies to. The discretion afforded by SEPA reaches to all levels of state government. As a result, this draft SEPA guidance will potentially make climate change an active issue to be addressed in a far broader range of governmental decisions.