TagThird Runway(1098)

A water resources consultant submitted comments to the Washington State Department of Ecology in September 2000, raising serious concerns about the Port of Seattle's proposed Des Moines Creek Flow Augmentation Facility, which was intended to mitigate water quality impacts from SeaTac Airport's third runway expansion. The consultant argues the plan is vague and incomplete, lacking secured water sources, hydrologic analysis, and finalized design details. Key technical problems identified include unreliable water temperature from one proposed source, dependence on continuous technological systems, and a disputed well design that may violate state groundwater protection guidelines.

Draft subsurface conditions data report prepared by HartCrowser for HNTB regarding the Third Runway Embankment at Sea-Tac International Airport, project numbers J-4978-23, -26, -27, and -31. Covers additional field explorations and advanced geotechnical testing including auger borings, standard penetration tests (SPT), Shelby tubes, pocket penetrometer, test pits, piezocone penetrometer probes, cone penetration tests (CPT), and

A September 2000 report by Azous Environmental Sciences, commissioned by the Airport Communities Coalition, critically analyzes the Port of Seattle's wetland mitigation plan for the SeaTac Third Runway construction project. The report identifies numerous errors in wetland acreage accounting, inadequate mitigation ratios, and flaws in the proposed compensatory measures, including out-of-basin mitigation that fails to replace lost wetland functions in the affected Miller, Walker, and Des Moines Creek watersheds. The author concludes that the Port's plan falls short of Washington State Department of Ecology standards and the regulatory goal of no net loss of wetland functions.

This September 2000 preliminary design report, prepared by Kennedy/Jenks Consultants for the Port of Seattle, outlines a plan to augment water flow in Des Moines Creek near Seattle-Tacoma International Airport. The report covers facility configuration, process components such as backflow prevention, dechlorination, and aeration systems, as well as an evaluation of chemical dechlorination alternatives. The project was designed to improve creek water quality by treating and releasing water in a controlled manner.

Internal email chain from Chung K. Yee to Kevin Fitzpatrick (Supervisor, Industrial Permit Unit, Water Quality Program, NWRO, Washington Department of Ecology) dated August 24, 2000, commenting on draft clean fill criteria language for the 401 Certification for the Third Runway at Sea-Tac Airport. Comments address sections E6, E7c.2(b), E7c.2(e), E7c.2(f), and E7c.3, covering issues

AR017487. Email from Chung K. Yee (Ecology, NWRO Water Quality Program) to Kevin Fitzpatrick dated August 24, 2000, commenting on draft clean fill criteria language for the 401 Certification for the Third Runway at Sea-Tac Airport. Comments address sections E6, E7c.2.(b), E7c.2.(e), and E7c.3, covering inappropriate fill, EPA databases, Confirmed & Suspected Contaminated Sites Report,

Draft memorandum dated August 21, 2000 from Jamie Beaver, Mike Bailey P.E., and Barry Chen P.E. of Hart Crowser, Inc. to Jim Thomson at HNTB (project J-4978-30) providing geotechnical design information for RECo for MSE wall and reinforced embankment fill design for the Third Runway Embankment at Sea-Tac Airport. Document includes minimum factors of safety

A wetland scientist hired by the Airport Communities Coalition reviewed the Port of Seattle's proposed wetland mitigation plan for the SeaTac Third Runway construction and concluded it was wholly inadequate. The report argues that the planned out-of-basin mitigation at an Auburn site fails to replace the wetland functions lost in the Walker Creek, Des Moines Creek, and Miller Creek watersheds, and that placing mitigation in a different drainage basin cannot scientifically compensate for local losses under Washington State environmental law. The reviewer also warns that the Auburn mitigation site faces multiple risks and is unlikely to be sustainable long-term.

Memorandum from Brian Pippin (Parametrix, Inc.) to Linda Logan (cc: John Brooker), dated August 14, 2000, Project Number 556-2912-001, Port of Seattle WERs. Discusses critical conditions for Water Effect Ratio (WER) sampling per the Permit Writers Manual for the third runway treated stormwater discharge into Miller Creek. Uses HSPF hindcasting over 49-year period to evaluate

Hart Crowser draft report prepared for Port of Seattle, August 9, 2000 (J-4978-13), evaluating perched groundwater zone interception and potential wetland hydrology impacts from Borrow Area 3 excavation for the Sea-Tac Third Runway project. Addresses Pacific Groundwater Group (PGG, 2000) concerns commissioned by Washington State Department of Ecology regarding impacts to Wetland 29. Includes ModFlow