TagMiller Creek(260)

Deliberative memo dated October 30, 2000, from Erik Stockdale (Ecology) to Jeannie Summerhays and Ray Hellwig regarding tasks for contractor Dyanne Sheldon. Recommends open-ended ‘Time and Materials’ contract and a firewall between Sheldon and Port Of Seattle. Tasks include evaluating natural resource mitigation plan (NRMP) for compliance with Section 401 of the Clean Water Act

Memorandum dated October 13, 2000 from Michael Bailey P.E. and Michael Kenrick P.E. of Hart Crowser to Jim Thomson P.E. at HNTB (project J-4978-06), analyzing infiltration into the proposed Third Runway embankment at Sea-Tac Airport and effects on shallow water-bearing zone base flow to Miller Creek and adjacent wetlands. Analysis uses three sequential models —

Internal memo from Erik Stockdale (Ecology) to Tom Luster, Kevin Fitzpatrick, Ray Hellwig, Dave Garland, Joan Marchioro, and Jeannie Summerhays, dated October 9, 2000, summarizing 23 remaining issues with the SeaTac Natural Resource Mitigation Plan (NRMP) for the Third Runway project at Seattle-Tacoma International Airport. Topics include: Ecology review transition and 3rd party wetland consultant

A September 2000 letter to the Washington State Department of Ecology raises concerns about the Stormwater Management Plan for Seattle-Tacoma International Airport's third runway expansion, arguing it fails to demonstrate compliance with the Governor's Certification requirement to avoid altering water flow between Miller and Des Moines Creeks. The letter also challenges the feasibility of proposed improvements to the airport's Industrial Wastewater System, citing inadequate modeling, unresolved capacity issues, and potential conflicts with FAA safety guidelines regarding wildlife attractants near runways.

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.

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 environmental consulting firm Azous Environmental Sciences alerts Washington State Department of Ecology officials to an unidentified tributary of Miller Creek that was overlooked in the Port of Seattle's environmental planning documents for Sea-Tac Airport's proposed third runway. The tributary, listed in King County Sensitive Areas records and confirmed to have active water flow, feeds into a Class 2 salmon-bearing stream but was never assessed for potential impacts in the Port's Natural Resource Mitigation Plan. The letter argues this omission—despite four years of environmental analysis—leaves the creek unprotected from planned construction and future aviation operations in the area.

A September 2000 letter from the Airport Communities Coalition to the Washington State Department of Ecology raises concerns about the adequacy of Seattle-Tacoma International Airport's Stormwater Management Plan submitted for 401 Certification. The letter identifies potential flaws in the analysis of base flow impacts on Miller Creek, inconsistencies between the new plan and earlier natural resource mitigation documents, and concerns about proposed changes to watershed basin boundaries. The authors argue that insufficient time was provided for proper review and that the plan fails to fully account for cumulative water quantity impacts of future development.

A September 7, 2000 letter from Northwest Hydraulic Consultants to the Washington State Department of Ecology raises concerns about the adequacy of the Port of Seattle's Stormwater Management Plan for Sea-Tac Airport's Master Plan expansion. The letter identifies significant technical discrepancies in the plan's analysis of baseflow impacts on Miller Creek, questions the reliability of proposed water-rights acquisitions as mitigation, and flags inconsistencies between the stormwater plan and the Natural Resource Mitigation Plan. The consultants also object to the limited time provided for independent review of the four-volume plan and warn that cumulative water quantity impacts of future commercial development in the airport acquisition area have not been adequately assessed.