Here is the definition, taken from the first paragraph of the City of Seattle's Department of Planning and Development's SEPA Checklist. Developers have to fill one of these out as part of the permitting process.
"The State Environmental Policy Act (SEPA), Chapter 43.21 RCW, requires all governmental agencies to consider the environmental impacts of a proposal before making decisions. An environmental impact statement (EIS) must be prepared for all proposals with probable significant adverse impacts on the quality of the environment. The purpose of this checklist is to provide information to help you and the agency identify impacts from your proposal (and to reduce or avoid impacts from your proposal, if it can be done) and to help the agency decide whether an EIS is required."Prior to our public meeting last Wednesday, several neighbors reviewed the SEPA checklist the Alki 11 developer filed with the city. They found inaccuracies and incomplete responses which they have addressed in both written comments and in their oral comments at the meeting.
If a project in your neighborhood is under SEPA review, this is what it is all about. To access the developer's checklist for that project, follow the instructions here. Fill in the project's Master Use Project (MUP) number. When the records come up, scroll down to find the SEPA checklist.
How To Access Permit and Property Records for Seattle Development Projects
The Environmental Impacts of the Alki 11 Row Houses
Will the Alki 11 Row Houses Cause Flooding?