EXH0638024628

Background: Paramvtrm has performed a prdiminary dilution analysis for proposed stormwater outfatls around STIA. Effluent mixing in streams is ordinarily evaluated at the 7Q10 and 30Q5 flows for chronic and acute zones, respectively. Although the 7Q10 and 30Q5 flows can be calculated from HSPF simulation lxsults for receiving streams around STIA, stormwater discharge would be quite unlikely during those conditions. For instance, the probability of stormwater discharge from the proposed 3RWN ouffall during either 7Q10 or 30Q5 Miller Creek flows is less than 0.000. This discussion focuses on a site-specific approach for performing the mixing zone analysis. 1. Alternate critical condition definition needed a. Based on 3RWN analysis, probability of stormwater discharge during 7Q10 and 30Q5 streamflow conditions appears to be extremely low (i.e.-P

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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 [...]