TagWater Quality(478)

Washington State Department of Ecology (Ecology) Water Quality Certification letter dated August 10, 2001, addressed to Port Of Seattle, Attn: Elizabeth Leavitt, for U.S. Army Corps of Engineers Public Notice 1996-4-02325. Certifies that construction of a Third Runway and related projects at Seattle-Tacoma International Airport (STIA) in the Miller, Walker, and Des Moines Creek watersheds

Washington State Department of Ecology Water Quality Certification (Order #1996-4-02325) issued August 10, 2001, to Port Of Seattle for construction of a 8,500-foot third parallel runway and related projects at Seattle-Tacoma International Airport (STIA) in the Miller, Walker, and Des Moines Creek watersheds and wetlands in SeaTac and Auburn, King County. Certifies compliance with Clean

Memorandum dated August 7, 2001 from Dave Garland, NWRO Water Quality Watershed Unit Supervisor, Washington State Department of Ecology, to Ann Kenny, Kevin Fitzpatrick, and Ray Hellwig, reviewing Parametrix Inc.’s July 2001 “Low Flow Analysis, Flow Impact Offset Facility Proposal” prepared for the Port Of Seattle regarding the proposed third runway at Sea-Tac Airport. Reviews

Memorandum dated August 7, 2001 from Dave Garland, NWRO Water Quality Watershed Unit Supervisor, to Ann Kenny, Kevin Fitzpatrick, and Ray Hellwig of the Washington State Department of Ecology Northwest Regional Office. Reviews the Parametrix Inc. July 2001 report ‘Low Flow Analysis, Flow Impact Offset Facility Proposal’ prepared for Port Of Seattle regarding predicted impacts

Memorandum dated August 7, 2001, from Katie Walter (Shannon & Wilson, Inc.) to Ann Kenny (Washington State Department of Ecology) regarding draft 401 conditions for the Port Of Seattle Natural Resource Mitigation Plan (NRMP), marked Deliberative — Do Not Disclose. Covers Auburn mitigation site culvert placement issues from the June 28, 2001 revised grading plan,

Memorandum dated August 7, 2001, from Katie Walter (Shannon & Wilson, Inc.) to Ann Kenny (Washington State Department of Ecology), marked ‘Deliberative – Do Not Disclose,’ regarding draft 401 conditions for the Port Of Seattle Natural Resources Mitigation Plan (NRMP), Auburn Mitigation Site. Document addresses culvert placement issues in the revised grading plan (June 28,

A water resources consultant, writing on behalf of the Airport Communities Coalition, argues that the Port of Seattle's July 2001 Low Flow Analysis for Sea-Tac Airport expansion fails to provide reasonable assurance that the project will meet water quality standards in Miller, Walker, and Des Moines Creeks. The letter criticizes the submission as incomplete and rushed, noting missing figures, unfinished sections, and an unresolved plan to store the required 46 acre-feet of stormwater across the three watersheds. The consultant contends that the Port's proposed water quality protections—including filtration, aeration, and biofiltration swales—are unproven, inadequately designed, and fall short of the regulatory standard required for Section 401/404 permit approval.

A August 6, 2001 letter from Water Resources Consulting L.L.C. on behalf of the Airport Communities Coalition critiques the Port of Seattle's 'Low Flow Analysis - Flow Impact Offset Facility Proposal' submitted in support of its Section 404/401 permit application for SeaTac Airport expansion. The letter argues that the Port's plan fails to provide reasonable assurance that the airport's stormwater management will meet water quality standards in Miller Creek, Walker Creek, and Des Moines Creek. Key concerns include an incomplete and unfinished proposal, insufficient stormwater storage capacity, unproven water quality treatment methods, and reliance on vague future 'adaptive management' rather than concrete, enforceable designs.

Draft memorandum dated 8/6/01 from Ray Hellwig, Director, Washington State Department of Ecology, to Tom Fitzsimmons, Director, recommending approval of a 401 Water Quality Certification for the Port Of Seattle’s Sea-Tac International Airport Third Runway project. Document covers 8,500-foot parallel third runway, Runway Safety Areas (RSAs), South Aviation Support Area (SASA), impacts to approximately 700

A biological scientist hired by the Airport Communities Coalition reviewed the Port of Seattle's plan to store airport stormwater in detention vaults and release it into Miller, Walker, and Des Moines Creeks during summer low-flow periods. The review found that the plan could worsen water quality in those creeks, because stored sediments may release toxic levels of copper and zinc, and potentially harbor human pathogens from airplane wastewater. The scientist concluded that regulators lacked sufficient information to approve the proposal without further testing, modeling, and independent scientific review.