TagACC(1534)

A February 2000 draft memorandum from Parametrix, Inc. outlines a scope and budget for range-finding Water-Effect Ratio (WER) studies using receiving water from Miller and Des Moines Creeks, conducted in connection with stormwater discharge permitting near the Port. The studies involve acute toxicity tests with copper-spiked water to determine whether site-specific water quality standards could be higher than generic state standards, potentially eliminating the need for a mixing zone. Estimated costs range from $2,110 for one creek site to $2,650 for two sites.

A February 2000 draft memorandum from Parametrix, Inc. outlines a scope and budget for range-finding Water-Effect Ratio (WER) studies using receiving water from Miller and Des Moines Creeks, intended to help determine whether copper discharge standards at a Port facility could be adjusted through site-specific water quality criteria. The studies involve acute toxicity tests comparing copper-spiked site water to copper-spiked laboratory water, with estimated costs ranging from $2,110 for one site to $2,650 for two sites. Results from earlier 1999 range-finding tests suggested WERs high enough to potentially justify more definitive studies, but new tests without mixing zone assumptions were recommended to better assess achievable permit limits.

Email from Erik Stockdale (Ecology NWRO) to Raymond Hellwig and Tom Luster, dated February 17, 2000, summarizing a February 15 meeting with Jim Kelley of Parametrix regarding public comments on the Sea-Tac Airport third runway project (AR 018438–018440, Exhibit 173). Issues raised by commenters Sarah Cooke and Andy Castelle concerned incorrect wetland mitigation ratio calculations

A February 2000 email from hydraulic consultant Bill Rozeboom argues that the proposed expansion of Sea-Tac Airport's Integrated Wetlands System (IWS) lagoon—tripling its storage capacity—is primarily driven by the airport's Master Plan Improvements, including the proposed third runway, rather than being a routine water quality project. Rozeboom notes that the planned increase in impervious drainage area (roughly 521 additional acres) closely mirrors the proposed increase in IWS storage volume, supporting his conclusion that the third runway is the primary driver of the expansion. He also raises concerns that the environmental documents fail to adequately assess the impact of large-scale out-of-basin water transfers on aquifer recharge and stream base flows in the Miller Creek and Des Moines Creek basins.

A February 2000 internal draft memorandum from environmental consultants to Port of Seattle staff summarizes efforts to develop a site-specific water quality criterion for copper in Miller, Walker, and Des Moines Creeks, in connection with stormwater runoff anticipated from a proposed third runway at Sea-Tac Airport. The memo evaluates two technical approaches—the Water-Effect Ratio (WER) and the site-specific metals translator—for potentially raising copper discharge permit limits, and outlines initial toxicity screening and range-finding study results. It also describes ongoing negotiations with the Washington State Department of Ecology regarding unresolved issues such as mixing zones, AKART requirements, and critical sampling conditions.

A February 2000 draft memorandum from environmental consultants to Keith Smith summarizes efforts to develop a site-specific water quality criterion for copper in Miller, Walker, and Des Moines Creeks near Seattle-Tacoma Airport, in anticipation of stormwater runoff from a proposed third runway. The memo outlines two technical approaches—the Water-Effect Ratio (WER) and the site-specific metals translator—for potentially raising copper discharge permit limits, and describes toxicity screening and range-finding studies conducted in 1999. The phased study approach was designed to avoid unnecessary costs if the WER method proved infeasible or if the Washington Department of Ecology would not permit its use in adjusting permit limits.

State of Washington interagency policy guidance (AR 034771, Exhibit 2193) adopted by Washington Department of Fish and Wildlife (WDFW) and Washington Department of Ecology (WDOE) for evaluating aquatic mitigation alternatives under section 401 of the Clean Water Act, the Shoreline Management Act (RCW 90.58), and the Hydraulic Code (RCW 75.20). Covers mitigation sequencing (avoiding, minimizing,

Email chain dated February 8, 2000 among Washington State Department of Ecology staff (Roger Nye, Raymond Hellwig, Steve Alexander) regarding fill criteria compliance for the Third Runway at Sea-Tac Airport. Roger Nye describes the 401/404 permit fill acceptance policy developed with Port Of Seattle governing contaminant criteria for borrow sources used in Third Runway construction

Letter dated February 1, 2000 from John Strunk, Associated Earth Sciences, Inc. (AESI Project No. BV97016D) to Roger Nye, Washington Department of Ecology Northwest Regional Office, submitting first and second quarter ground water level measurements from the C1 (Qva) aquifer monitoring well network at Seattle-Tacoma International Airport. Reports on six pressure transducers installed in the

Memorandum BV97016D dated January 31, 2000, from John Strunk (Associated Earth Sciences Inc.) and Mike Riley (S.S. Papadopulos & Associates, Inc.) to Roger Nye, Department of Ecology, responding to nine Ecology comments on the Conceptual Flow Model Boundary Presentation for the Seattle-Tacoma International Airport ground water study. Topics addressed include MODFLOW model setup covering approximately