TagSea-Tac Airport(2025)

This December 2001 letter from the U.S. Fish and Wildlife Service's Western Washington office provides detailed comments on a Monitoring Plan for Embankment Fill Seepage related to a Sea-Tac Airport Master Plan Update, reviewed under the Endangered Species Act. The agency requested key revisions, including monitoring both seepage quality and quantity, beginning monitoring when seepage first occurs rather than after embankment completion, and ensuring groundwater wells are considered as a monitoring pathway. The letter also clarified that any exceedances of water quality criteria must be reported promptly, and that the Federal Aviation Administration—not the Port—would be responsible for reinitiating formal consultation.

Memorandum dated December 20, 2001 from Michael Bailey, P.E. and Reda A. Mikhail, P.E. of Hart Crowser, Inc. to Jim Thomson, P.E. of HNTB Corporation regarding AR053223, project 4798-40. Analyzes sensitivity of MSE (Mechanically Stabilized Earth) wall design to variations in soil shear modulus under dynamic/seismic loading for the Third Runway Project at Sea-Tac Airport,

Letter dated December 20, 2001 from Ken S. Berg, Manager, Western Washington Fish and Wildlife Office (U.S. Fish & Wildlife Service) to James M. Lynch, Stoel Rives LLP, providing 20 numbered comments on the Monitoring Plan for Embankment Fill Seepage submitted August 10, 2001 under Endangered Species Act consultation 1-3-00-F-1420 (Sea-Tac Airport Master Plan Update).

Memorandum dated December 12, 2001 from Michael Kenrick and Reese Hastings of Hart Crowser Inc. to Jim Thomson of HNTB, project number 4978-62, analyzing pre-construction and post-construction hydrologic conditions at Borrow Area 1 associated with the Port of Seattle Master Plan Update for Sea-Tac International Airport (STIA). Covers surface water and groundwater impacts, wetland hydrology,

Parametrix, Inc. report prepared for Port of Seattle, Seattle-Tacoma International Airport Master Plan Update Improvements, December 2001. AR 052659/052660/052661. Volume 1 includes main text and Appendices B through J. Sub-consultants include Aqua Terra Consultants, Earth Tech Inc., Foster Wheeler Environmental Corporation, HNTB, and Pacific Groundwater Group. Addresses low streamflow analysis and summer low flow impact

Wetland Functional Assessment and Impact Analysis prepared by Parametrix, Inc. for Port Of Seattle, December 2001, project number 556-2912-001 (03). Assesses wetland functions and impacts associated with Seattle-Tacoma International Airport Master Plan Update Improvements including the new Third Runway, Runway Safety Areas (RSAs), relocation of South 154th Street, Borrow Area 1 excavation, South Aviation Support

This December 2001 report, prepared by Parametrix, Inc. and several partner firms for the Port of Seattle, analyzes low streamflow conditions and proposes a Summer Low Flow Impact Offset Facility as part of the Seattle-Tacoma International Airport Master Plan Update Improvements. The study examines how planned airport expansion may affect seasonal low-flow water resources in the surrounding area and outlines mitigation measures to offset those impacts. The report is organized across multiple volumes, with Volume 1 containing the main text and Appendices B through J.

This document presents site features and cross-sectional diagrams used for Hydrus-Slice hydrological modeling of the Sea-Tac Third Runway Embankment Fill project. It shows fill depths ranging from 0 to 160 feet across multiple modeled slices, with cross sections identifying impervious areas, elevation contours, and the watershed divide between Miller Creek and Walker Creek. The figures were produced in November 2001 as part of environmental engineering analysis for the third runway construction.

Draft map prepared by Parametrix, Inc. on November 07, 2001, AR 051191. The document is a draft aerial/planning map showing what appears to be the Sea-Tac Airport area and surrounding communities, with various zones, boundaries, and site designations marked. Labeled as draft and subject to change.

A 2001 technical memo from Hydrocomp, Inc.'s Norm Crawford outlines recommendations for hydrological modeling of Miller, Walker, and Des Moines Creeks near Sea-Tac Airport's new runways and taxiways. The document describes how surface runoff and groundwater flow from both impervious runway surfaces and surrounding pervious grasslands should be calculated and linked across three modeling tools: HSPF, Hydrus, and the Slice model. Key recommendations include properly accounting for infiltration, reducing till seepage by 33% for inactive groundwater recharge, and reconciling discrepancies in land area calculations between the different models.