EXH0634024616

_ if significant changes occur in the receiving water or in the effluent. The reevaluation may be reduced in scope from the original determination but will include toxicity testing and receiving water _alysis at the critical condition. b. WET testing will be required in the permit. c. A receiving water bioassessment _ay_e required in complex discharge situations... d. Regardless of the magnitude of the WER determined in a WER study, Ecology will only _ authorize the highest WER that allows a permittee to fall below the "reasonable potential" threshold. 6.3. Sample-Specific WER approach (EPA pg 13-15) Tbe implementation process for this approach is not fully developed in the EPA guidance document and is not applicable to discharge situations. 6.4 Determining WERs for areas in. or near plumes (Method _ 1). (EVA pg 17) The WER in fresh _ sho_ld be determined using: a. upstream water _ 0 _' ' _-_ C), b. simulated downstream water at the acute dilution factor _t_d) 0 c. Simulated downstream at the complete mix ratio when the-dilution factor for complete mix is 20 or less. When the dilution factor is greater than 20 for complete mix, use simulated downstream water at the chronic dilution factor. The WER in salt water should be determined using: a. Water from the area of discharge but away from the influence of the discharge b. Simulated effluent/receiving water at the chronic dilution ratio. 7%6.5 Design flows for WER(s) The WER's should be measured three times at the time o.fcritical condition…

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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 [...]