EXH2097033691

TO: Ann Kenny, NWRO Shorelands and Environmental Assessment Program Kevin Fitzpatrick, NWRO Water Quality Program FROM; Dave Garland, NWRO Water Qua_/_, _, SUBJECT: Sea-Tac Third Runway Borrow Area 3 Wetland Impacts Recommendations for Wetland Preservation BACKGROUND; This memo constitutes my final review comments on potential wetland impacts from the Port of Seattle proposal to excavate sand and gravel fill material from a borrow pit located just south of Sea- Tac Airport. The borrow pit, known as Borrow Area 3, is proposed to be excavated to provide some of the material needed for the proposed Sea-Tac Third Runway fill embankment. Concern for hydrologic impacts from mining in Borrow Area 3 beE'an when independent hydrologic studies conducted for Ecology by Pacific Groundwater Group (PGG, 2000) concluded that the proposed excavation "would likely have substantial impacts to wetland water flows, and possibly biota."(pg. 74) "Ihere are three wetlands located in Borrow Area 3 that are over one-half acre in area, arid four smaller wetlands less than 0.1 acre. The proposed excavation in Area 3 is designed to narrowly avoid these seven wetlands and excavate sand and gravel to depths slightly lower (10 - 20 feet) th_n the elevations of the wetlands. Groundwater flow direction near Borrc_wArea 3 was :mcertair_ a" the time of the PGG report, but now has been determined to be generally from the northwest. Recharge to the wetlands is believed to be partially dependent on water from a perched water-bearing zone. The excavation proposal is to remove the perched water-beating…

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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 [...]