EXH1295052146

To: Port of Seattle project files October 5, 2001 From: Todd Pollard / Linda Logan 556-2625-002 (01/01) Subject: Summary of analytical results from 1-14-99 storm water sampling This memorandum summarizes the results of chemical analysis conducted on STIA receiving stream samples collected January 14, 1999. The primary objective of the January 14msampling was to evaluate the toxicity of STIA receiving streams through screening level bioassays conducted by Parametrix, Inc.. Results of the screening level bioassays can be found in Parametrix 1999. Sampling Samples were collected from 8 locations during a storm event (as defined in the POS Procedure Manual for Stormwater Monitoring) on the morning of 14 January 1999. The antecedent dry period preceding this storm was 86 hours. Precipitation started at 1600 on January and ended at 1600 on 14 January 1999; samples were taken from approximately 0700 to 1000 on 14 January. Approximately 1.18 inches of rain fell at STIA during this 24-hour storm. Parametrix staff collected two-liter grab samples at 15-minute intervals over a three-hour period from seven of the eight sampling sites. Samples were placed on ice immediately after collection, and delivered to the Parametrix laboratory shortly after collection of the last grab sample at each location. Within 4 hours of receipt by the laboratory, all grab samples were flow-weight-cqmposited into a 10-liter cubitainer based on flow estimates. Flow at each location was estimated by entering stage measurements into the Manning or empirical stage-discharge equations. POS staff collected samples at the eighth location (SDS-3), with an…

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PSCAA Advisory Council Meeting Agenda
Add to CalendarMWednesday Mar 11, 9:00am - 11:35am
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Call to order – Roll Call – Quorum Established – Land Acknowledgement We would like to acknowledge that our Agency operates in four present-day counties, which are the traditional lands of the Coast Salish people, past and present. This acknowledgement does not take the place of authentic relationships with indigenous communities in our jurisdiction and [...]