Notes
Draft memorandum dated April 20, 2000, authored by Doug Henderson and Linda Logan (job number 556-2912-001) for Port of Seattle project files, summarizing range-finding water-effect ratio (WER) toxicity tests for copper in streams receiving Seattle-Tacoma International Airport (STIA) stormwater. Tests used Daphnia magna as indicator species; copper was spiked into site water and synthetic laboratory water to determine LC50 values and calculate WERs. Samples collected April 13–14, 2000 during a qualifying storm (0.34 inches rain, 74-hour dry antecedent period) at five sites: Miller Creek Upstream, Miller Creek Detention Facility, Northwest Ponds Outlet, Northwest Ponds Inlet, and Des Moines Creek Weir. Flow-weighted composite samples collected by Taylor Associates using ISCO samplers. Copper stock solution (CuSO4·5H2O, CAS#7758-99-8) verified at 500.0 mg/L by Battelle. Tests conducted per EPA/600/4-90/027F, August 1993. AR 042316–AR 042318.