TagWater Quality(478)

ACC (Airport Communities Coalition) motion filed with the Pollution Control Hearings Board (PCHB No. 01-160) seeking to supplement the evidentiary record on its motion for stay of the Section 401 Certification issued by Ecology on September 21, 2001, for the Third Runway Project at Sea-Tac Airport. Documents obtained via public records request to Ecology on

In November 2001, the Port of Seattle submitted a Third Runway Embankment Seepage and Groundwater Monitoring Plan to the Washington Department of Ecology as required by a § 401 Water Quality Certification order. The plan was designed to detect any impacts of the runway fill embankment on nearby receiving waters and groundwater, both during and after fill placement. The Port requested written approval of the plan from the Department of Ecology's Northwest Regional Office.

Port Of Seattle letter dated November 16, 2001 from Elizabeth Leavitt, Manager of Aviation Environmental Programs, to Ann Kenny at the Washington Department of Ecology Northwest Regional Office, transmitting the Third Runway Embankment Seepage and Groundwater Monitoring Plan in satisfaction of § 401 Water Quality Certification Order #1998-4-02325, Condition E.3. The plan, AR 052417–052419, covers

Port Of Seattle’s objections filed November 15, 2001 to three issues proposed by Airport Communities Coalition (ACC) in Pollution Control Hearings Board (PCHB) Case No. 01-160, concerning §401 certification for the Third Runway project. Objects to ACC Proposed Issues 11, 18, and 19: Issue 11 concerns dam safety permit requirements under WAC 173-175 and reasonable

Respondent Washington State Department of Ecology’s objections filed before the Pollution Control Hearings Board (PCHB No. 01-133, PCHB No. 01-160) to issues proposed separately by Airport Communities Coalition (ACC). Ecology objects to ACC Issue No. 2 as outside the Board’s jurisdiction over the 401 Certification, and to ACC Issue No. 3 as duplicative, vague, and

A 2001 technical memo from Hydrocomp, Inc.'s Norm Crawford outlines recommendations for hydrological modeling of Miller, Walker, and Des Moines Creeks near Sea-Tac Airport's new runways and taxiways. The document describes how surface runoff and groundwater flow from both impervious runway surfaces and surrounding pervious grasslands should be calculated and linked across three modeling tools: HSPF, Hydrus, and the Slice model. Key recommendations include properly accounting for infiltration, reducing till seepage by 33% for inactive groundwater recharge, and reconciling discrepancies in land area calculations between the different models.

A study at Seattle-Tacoma International Airport found that galvanized metal roofing on cargo buildings was the primary source of elevated zinc levels in the airport's stormwater runoff, which drains into salmon-bearing streams including Miller Creek and Des Moines Creek. Researchers used whole effluent toxicity (WET) testing and source-tracing methods to identify the problem, focusing on one outfall (SDN1) that consistently showed higher zinc concentrations and toxic effects on aquatic organisms. The findings prompted the Port of Seattle to investigate remediation options as part of its stormwater pollution prevention program under its NPDES permit.

This 2001 email chain discusses how fill materials used in the construction of Seattle-Tacoma Airport's Third Runway Embankment should meet environmental criteria under a 401 water quality permit. State regulators and Port of Seattle staff debated which materials — including topsoil, utility backfill, base course, and general embankment fill — required testing, supplier certification, or quality assurance plans to demonstrate compliance. Officials agreed that highly processed materials like topsoil could be covered by supplier certification, while bulk embankment fill would require a statistical sampling and QA/QC program.

Final meeting notes from October 30, 2001 Low Flow Analysis meeting regarding Port Of Seattle’s revisions to the Low Streamflow Analysis and Summer Low Flow Impact Offset Facility Proposal per 401 Permit conditions for Sea-Tac Airport Third Runway. Attendees included Ann Kenny (Dept. of Ecology), Kelly Whiting and David Masters (King County), Lisa Scott (Corps

Email from Kelly Whiting (King County Department of Natural Resources, Water and Land Resources Division) to Ann Kenny and Raymond Hellwig, dated October 25, 2001, summarizing a pre-meeting briefing on revised low flow hydrologic modeling related to Port Of Seattle airport embankment impacts. Discusses Hydrocomp (Norm Crawford) independent review findings, HSPF modeling errors including incorrect