Notes
AR026488. Water quality assessment (WQA) summary prepared by Parametrix in support of the Port Of Seattle Master Plan Update for Seattle-Tacoma International Airport (STIA), filed in PCHB proceedings related to the third runway EIS. Document describes a three-pronged approach: (1) Water Effect Ratio (WER) / Indicator Species Procedure to modify state water quality standards for copper under US EPA 1984 guidelines; (2) mixing zone analysis to determine point of compliance in receiving streams; (3) stormwater quality variability examination. References NPDES permit No. WA-002465-1, 401 certification, Washington Department of Ecology, LC50 toxicity testing per US EPA 1993 and Ecology Publication WQ-R95-80, Parametrix toxicity testing laboratory in Kirkland WA, best management practices (BMPs), and stormwater/receiving water hydrograph modeling for post-third-runway construction conditions.