The State Environmental Policy Act (SEPA), Chapter 43.21C RCW, was enacted in 1971 and provides the framework for agencies to consider the environmental consequences of a proposal before taking action. SEPA gives agencies the ability to condition or deny a development proposal due to identified likely significant adverse impacts.
SEPA is implemented through the rules (Chapter 197-11 WAC).A categorical exemption is a type of government action that is specifically designated as being exempt from SEPA compliance because it is unlikely to have a significant adverse environmental impact.
Certain proposals are exempt because they are of the size or type to be unlikely to cause a significant adverse environmental impact.
For single-family residential dwelling units, up to 30 dwelling units
For multifamily residential dwelling units, up to 60 units
For barns, loafing sheds, farm equipment storage, produce storage or packing structure buildings, up to 40,000 square feet
For office, school, commercial, recreational, service or storage buildings, up to 30,000 square feet of gross floor area and with associated parking facilities designed for up to 90 parking spaces - This exemption includes stand-alone parking lots
For landfills and excavations, up to 1,000 cubic yards
You may find the requirements and application process in the Spokane Valley Municipal Code (SVMC) 21.20