EXH1151043696

of the two that may receive more deicing chemical applications. Thus, Des Moines Creek, particularly cell NP3 of NWP, has the potential to receive the highest loading from ground deicing chemicals than would other STIA drainage. Moreover, because of the potential for extended detention periods in NWP, this water body, specifically cell NP3, has the potential to experience greater oxygen consumption from deicing chemicals than any other water body receiving STIA runoff. Subbasin SDS1 no longer drains any ramp or landside areas subject to routine ground deicing. Subbasin SDS4 drains 7% of the airfield impervious surfaces and drains directly to Des Moines Creek below Tyee pond. Other minor subbasins in the Des Moines Creek watershed include SDS2, SDS5, SDS6 and SDS7, none of which experience routine ground deicing. Together, these four STIA subbasins drain 2.8% of the total impervious area. However, runoff from these subbasins enters cells NP1 and NP2 combined with drainage from other entities, including City of SeaTac (S. 188th St). Similar to the Lake Reba drainage, streets and parking in these non-Port areas could be subject to ground deicing by these other entities. 2.1.1 Ground Deicing Chemicals and Ooerations The Port tracks and reports all applications of PA, SA and CMA ground deicing chemicals. These reports have been used to design the outfall sampling programs for this project and previous studies (POS, 1999c). Liquid PA (Cryotech E36 LRD)is used principally on the airfield and ramp areas. Solid CMA and SA (both Cryotech products) are used primarily on…

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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 [...]