EXH1010034995

Summary of mitigation actions taken to avoid and minimize wetland impacts. Mitigation Action Mitigation Requirement Avoid the impact by not Avoid fill in wetlands and Miller Creek by desi_nlnp the runway to meet the t,kin_ a certain actionor minimumopera_onal,en_ safety,andmaintenancestandards. partsof anaction. Locate,wherefeasfole,pemanentsu,.mwaterdetentionpondsin uplands.Avoid excavationwithin 50 fl of Category!1and111weflsntk in Borrow Area3. Avoid wetlands in Borrow Areal where practical. C.onsm_ retainingwalls at the northwestend of the runway to reduce impacts to Miller Creekand Category II wetlands(Wetlatah 8, 9, and A1) located at the north end of theproject. Install a retainingwall near the west-centralportion of the enfl_-kngnt to reduce impacts to Category 11Wetlands 18 and 37 and avoid relocating a second segment of MillerCreek. Minimi'p_ the impact by place a _ wall near thc _,hwest end of the nmway to reduce impact to a limiting the degree or CategowHwethnd(Wetbnd44). magnitude ofthe action. Design Borrow Areas I and 3 witha 150- to 200-fl setback fromDes Moines Ct_k to minimizepotentinl impa_ to the=ream andits buffers. Implement stormwater pollution prevention plans (SWPPPs) prior to any - _ I_roject. Maintainhydrologyto wetlandsby directingseepage water fromthe embankmentto wetlandsdownslope of the Provide water quantityand water quality mitigation to protect aquatic habitat in Miller Creekfromstormwaterimpacts duringoperation. Avoid the impact by not Constngt retaining walls to support relocated South 154" Street and avoid taking a certain action or penmnent fill in Wetlands3 and4. partsof an action. Minimize the impact by Construct retaining walls to support relocated South 154' Street and reduce lin_ting the degree or penmnent fill and minimizetempcmuyimpacts in…

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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 [...]