Posted on

EXH AR023827: Draft Meeting Notes — Low Flow Analysis, STIA Third Runway (Jun 12, 2001)

Document Library
Sea-Tac Airport
Third Runway
PCHB
Box 10

These draft meeting notes from June 12, 2001 document a technical status meeting between the Washington Department of Ecology, King County, and the Port of Seattle regarding low stream flow analysis for the Sea-Tac International Airport Third Runway project. The group reviewed progress on hydrological modeling efforts, including HSPF and Hydrus modeling used to assess how runway embankment construction might affect nearby stream flows. Discussions also covered planned mitigation measures such as stormwater retention vaults, upcoming modeling deliverables, and a follow-up conference call that confirmed the Port team's modeling methodology was acceptable and conservative for evaluating embankment seepage.

Open full document

Notes

Draft meeting notes prepared by Kate Snider (Floyd & Snider Inc.) from a June 12, 2001 status meeting on Low Stream Flow analysis for the Sea-Tac International Airport Third Runway 401 Permit decision-making process. Attendees included Ann Kenny and John Drabeck (Dept. of Ecology), Kelly Whiting (King County), Keith Smith (Port of Seattle), Paul Fendt (Parametrix), and Charles Ellingson (Pacific Groundwater Group). Topics covered: HSPF and embankment seepage modeling status, Hydrus modeling (10′ and 20′ thicknesses for thin fill areas), slice cross-sections, Effective Recharge (ER) methodology, Recharge 1 vs. Recharge 2 comparison, non-hydrologic effects deliverable D-11 under SMP process, pre- and post-project hydrographs for 1991–1994 dry year period, stormwater retention vault sizing for mitigation, and a follow-up conference call on 6/13 with Joe Brascher, Pony Ellington, Aquaterra, and Pacific Groundwater Group confirming Recharge 1 methodology acceptable for evaluating embankment seepage. Administrative Record numbers AR 023827–AR 023829.

Sidebar On/Off
V V