TagACC(1531)

A September 2000 letter from Northwest Hydraulic Consultants raises concerns about the Stormwater Management Plan for Seattle-Tacoma International Airport's third runway expansion, finding that it fails to demonstrate compliance with the Governor's Certification requirement to protect water flow in Miller and Des Moines Creeks. The letter also identifies serious problems with the airport's plan to manage stormwater through expansions to its Industrial Wastewater System, including unresolved engineering uncertainties and potential conflicts with FAA wildlife safety guidelines that prohibit wastewater facilities within 10,000 feet of runway areas.

Attorney-client privileged deliberative document dated September 27, 2000, from Gordon White (Washington Department of Ecology, Shorelands and Environmental Assistance Program) to Tom Luster, Raymond Hellwig, Kevin Fitzpatrick, Joan Marchioro (ATG), and Erik Stockdale. Transmits draft letter to M.R. (Mic) Dinsmore, Executive Director, Port Of Seattle, regarding 401 Water Quality Certification review for the Third Runway

Internal deliberative email chain dated September 27, 2000, among Washington State Department of Ecology staff Tom Luster, Raymond Hellwig, Kevin Fitzpatrick, Joan Marchioro (ATG), and Erik Stockdale, marked Attorney Client Privileged. Discusses draft denial letter and withdrawal letter related to the Dinsmore 401 water quality certification review for a Port Of Seattle project (Sea-Tac Airport).

Internal email chain dated September 27, 2000, among Washington State Department of Ecology staff Tom Luster, Raymond Hellwig, Joan Marchioro (ATG), Kevin Fitzpatrick, and Erik Stockdale, forwarded to Gordon White, marked ‘Attorney Client Privileged’ and ‘Deliberative Document.’ Concerns the Dinsmore project draft 401 certification denial letter and withdrawal letter (AR017924–017926). Luster raises concerns that the

A September 26, 2000 letter from Water Resources Consulting L.L.C. to the Washington State Department of Ecology critiques the Port of Seattle's plans to augment water flow in Des Moines Creek, a project related to Sea-Tac Airport operations. The letter identifies several serious flaws in the proposal, including the lack of a secured water source, concerns about water temperature and fluoride toxicity to fish, and a maintenance-intensive design prone to failure. The author concludes that the Port's 'preliminary design' does not provide reasonable assurance that water quality standards will be met.

This September 2000 letter from environmental reviewers raises concerns about the Seattle-Tacoma International Airport third runway expansion project, specifically arguing that the Port of Seattle's Stormwater Management Plan fails to adequately assess or mitigate reductions in stream base flows and seepage flows to nearby wetlands. The reviewers present hydrological modeling data suggesting that groundwater inputs to Miller Creek could be reduced significantly more than the Port's own estimates indicate, and that the fill embankment's actual drainage behavior contradicts the Port's claims that it would function like natural outwash soil. The letter challenges the Port's assurances that seepage flows to downstream wetlands would be preserved, citing conflicting data within the Port's own documents and questioning the reliability of the analyses used to support those claims.

A September 2000 letter from Northwest Hydraulic Consultants raises concerns that the Seattle-Tacoma International Airport's Stormwater Management Plan fails to adequately assess or mitigate the third runway embankment's impact on stream base flows and seepage flows to nearby wetlands. The consultants argue that the Port of Seattle's own data contradicts its claims that the embankment fill would maintain groundwater recharge, and that independent re-analysis suggests summer groundwater reductions to Miller Creek could be roughly twice what the Port reported. The letter calls for more rigorous and consistent hydrologic modeling before construction commitments are made.

A September 2000 letter from Northwest Hydraulic Consultants, written on behalf of the Airport Communities Coalition, raises serious technical concerns about the Stormwater Management Plan for Seattle-Tacoma International Airport's proposed third runway. The letter highlights findings from King County reviewers showing that multiple stormwater facilities in the plan were unverified, potentially infeasible, or unlikely to meet required flow control performance standards. The consultants argue that the review timeline was insufficient and that the Port of Seattle had a history of failing to deliver promised stormwater mitigation measures.

In September 2000, Northwest Hydraulic Consultants submitted preliminary technical comments on behalf of the Airport Communities Coalition, raising serious concerns about the adequacy of the Stormwater Management Plan for Seattle-Tacoma International Airport's proposed third runway expansion. The letter highlights findings from King County's independent review, which identified numerous cases where proposed stormwater control facilities were unverified, infeasible, or unlikely to meet required flow control performance standards. The consultants warned that the compressed public review timeline was insufficient for thorough evaluation of the plan before Ecology's 401 Certification decision.

A water resources consultant hired by the Airport Communities Coalition reviewed Sea-Tac Airport's August 2000 Stormwater Master Plan and found it seriously deficient in protecting local water quality. The review concludes that existing pollution controls at the airport are not working, that stormwater discharges regularly violate Washington State Water Quality Standards, and that the Plan's proposed measures fail to provide reasonable assurance that those standards will be met in the future. Key concerns include the diversion of polluted runoff away from local creeks, inadequate handling of metal roof runoff, and the lack of meaningful mass-balance accounting for long-lived pollutants.