Notes
This document describes the Washington State Department of Ecology’s review process for Section 401 water quality certificates required before the U.S. Army Corps of Engineers can permit wetlands filling for Sea-Tac Airport’s third runway. It details three successive applications filed by Sea-Tac Airport, culminating in a temporary stay of the third certificate granted by the Pollution Control Hearings Board following an appeal by the Airport Communities Coalition. The PCHB identified three major issues of concern: contaminated fill, lack of water rights for stream augmentation, and adequacy of wetlands mitigation.