EXH0723026486

Re: Development of a site-specific copper translator for the Port of Seattle The purpose of this memorandum is to summarize the options available for developing a site- specific metals translator. In developing a translator, WDOE recommends conducting a dissolved/total recoverable metal partitioning study that incorporates seasonal variation. Mark Hicks at Ecology., the primary contact for the Washington State Water Quality Standards Manual (WAC 173-201A), could not provide much information on site-specific translators and is not aware of any studies that have been conducted in the state. He also mentioned that there would be an intensive review process of the first site-specific translator proposed in Washington State. We have obtained two documents outlining a translator study: 1) Prothro (1993), attachment B from the Water Qualily Standards Handbook, and 2) The Metals Translator: Guidance For Calculating A Total Recoverable Permit Limit From A Dissolved Criterion (1996) (EPA 823-B- 96-007). To conduct a partitioning study, total recoverable and dissolved metal samples need to be collected over time. In Prothro, the EPA recommends at least four pairs of total recoverable and dissolved metal measurements be made during low flow conditions or 20 pairs over all flow conditions. The EPA also suggests that the average of data collected during low flow or the upper 95thpercentile for all flows be used. Another approach to developing a site-specific translator is discussed in both Prothro and The EPA Metals Translator document. Using historical data on TSS and I_ values from the Technical Guidance Manual for Performing Ff'ZA 's…

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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 [...]