EXH0729026593

Re: Review of Dra_ De-Icing Dissolved Oxygen Report Parametrix has reviewed the Draft De-Icing Dissolved Oxygen Report, and submits the following comments: • The report should be simplified to clearly state that there is no evidence that state water quality standardsfor DO are violated in Miller Creekand Des Moines Creek. There is much focus on relatively minordetails. The report's emphasis should be on the overall non-effect in Miller Creek andDes Moines Creek. • As a point of reference, both the executive summary and the introduction should quote the June 9, 1998 letter from Lisa Au_n of Ecology, stating "Unless the Port canshow that the dissolved oxygen _DO) in Miller and Des Moines Creeks is not lowered below the water quality standard (9.5 rag/L) by the washoff of acetate from the runways and taxiways, the first flush from the runwaysand taxiwayswill have to be collected and treated." Startwith the hypothesis that DO in the streamsis affected by de-icing chemicals. The report should subsequentlyshow that there is no significant evidence that this hypothesis is correct;that is, the state water quality standard for DO was not violated in the creeks following the de-icing events (although the letter states the 9.5-mg/L standardfor Class A.A.streams, the report should use the 8-mg/L standardfor Class A). • Contrary to the current position stated in the report, it does not appear that the data conclusively demonstrates that de-icing chemicals do not affect DO in the NW Ponds and Lake Reba. However, the reportshould use the data, coupled with…

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PSCAA Advisory Council Meeting Agenda
Add to CalendarMWednesday Mar 11, 9:00am - 11:35am
1904 3rd Avenue, Suite 105, Seattle, WA 98101
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 [...]