TagACC(1534)
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1999-10-08EXH AR043079: Hart Crowser Memorandum — Sea-Tac Airport Third Runway Probabilistic Seismic Hazard Analysis Results
Hart Crowser memorandum from Michael Bailey, Allen Jones, and Doug Lindquist to Jim Thomson (HNTB), dated October 8, 1999, presenting probabilistic seismic hazard analysis (PSHA) results for the Sea-Tac Airport Third Runway project (J-4978-14). Reports peak horizontal acceleration (PHA) values for common design return intervals: 0.16 g (72-year), 0.36 g (475-year), 0.47 g (975-year), and -
1999-09-24EXH AR042987: Subsurface Conditions Data Report, Borrow Areas 1, 3, and 4, Sea-Tac Airport Third Runway
Hart Crowser subsurface conditions data report (project J-4978.02) prepared for HNTB and Port Of Seattle, dated September 24, 1999, covering Borrow Areas 1, 3, and 4 for the Sea-Tac Airport Third Runway project. Report includes generalized geologic conditions, subsurface soil conditions, hydrogeologic regime, groundwater elevation data, and perched water-bearing zone analysis. Field explorations used dual-wall -
1999-09-20EXH AR024773: Parametrix Memo — Review of 1999 Annual Stormwater RP, STIA
A September 20, 1999 internal memorandum from Parametrix, Inc. consultants to Scott Tobiason provides technical review comments on the first draft of the 1999 Annual Stormwater Report for Seattle-Tacoma International Airport (STIA). The memo raises concerns about consistency in water quality comparators, statistical methods for 'trimmed' data sets, and the attribution of reduced sediment levels to construction wheel wash versus other factors. It also flags regulatory issues regarding mixing zones, water quality standards language, and potential NPDES permit compliance implications of identifying pollution sources in the annual report. -
1999-09-17Exhibit 165: RE: Sea-Tac Third Runway — 401 Certification Timing and Governor’s Commitment
Email chain from Raymond Hellwig (Washington State Department of Ecology) to Thomas Fitzsimmons and Bill Alkire, cc’ing Carol Jolly, Ron Langley, Tom Luster, Kevin Fitzpatrick, Dave Garland, Erik Stockdale, Roger Nye, and Paul David Carr, dated September 17, 1999. Discusses Governor’s reported commitment to Sea-Tac legislators (Paterson et al.) that the Section 401 Water Quality -
1999-09-16Exhibit 2115: Internal Email — Ecology on Sea-Tac Water Quality Standards Compliance, Des Moines Creek 401 Certification
Internal email from Tom Luster (Ecology) to Raymond Hellwig, Kevin Fitzpatrick, Erik Stockdale, and Paula Ehlers, dated September 16, 1999, regarding SeaTac Airport 401 certification and compliance with water quality standards under the Clean Water Act. Discusses non-attainment of water quality standards in Des Moines Creek and Miller Creek, antidegradation requirements, Level 2 detention requirements, -
1999-09-16EXH AR042985: Fax Transmittal and Map — Proposed Groundwater Level Monitoring Well Network, STIA Groundwater Study
Fax transmittal dated 9/16/99 from John Strunk of Associated Earth Sciences, Inc. (Bainbridge Island, WA) to Roger Nye at Ecology, transmitting a map showing proposed well locations for measuring groundwater levels at Seattle-Tacoma International Airport (STIA). The attached map titled ‘Proposed Groundwater Level Monitoring Well Network, STIA Groundwater Study’ (September 16th, 1999) shows on-site and -
1999-09-16EXH AR027877: Internal Email on Unresolved Sea-Tac Stormwater Issues — 401/CZM Review, Des Moines Creek RDF, and Water Quality BMPs
Internal email from Tom Luster (Washington State Department of Ecology) to Raymond Hellwig, Kevin Fitzpatrick, Erik Stockdale, and Paula Ehlers dated September 16, 1999, outlining unresolved stormwater issues in the 401/CZM review of Port Of Seattle’s Sea-Tac Airport Master Plan Expansion. Topics include: definitions of ‘modified Level 1’ and ‘Level 2-type flow control’; role of -
1999-09-08
ACC: Letter to the Editor: It’s never too late to save over a billion dollars in public funds
City of Burien City of Tukwila City of Des Moines City of Federal Way City of Normandy Park Highline School District AIRPORT COMMUNITIES COALITION September 8, 1999 To the Editor: It’s never too late to save over a billion dollars in public funds. It’s not too late to ease freeway gridlock. And it’s not -
1999-09-07EXH AR024681: Sensitivity Analysis Mixing Zone Parameters (cont.) — Stormwater Mgmt
A 1999 technical memorandum from Parametrix, Inc. analyzes whether stormwater discharged near Des Moines Creek meets Washington State dissolved copper water quality criteria, using a Monte Carlo simulation model. The analysis finds that copper levels in the stormwater effluent consistently exceed water quality standards regardless of background ambient concentrations, with dilution factors generally less than 2. The study evaluates several potential remedies, including increased onsite detention, expanded mixing zones, and water effect ratio adjustments, finding that the Water Effect Ratio (WER) is the most influential factor in achieving compliance. -
1999-09-01EXH AR018047: Annual Stormwater Monitoring Report for Seattle-Tacoma International Airport, July 1, 1998 – June 30, 1999
Annual stormwater monitoring report (AR018047) prepared by Port Of Seattle for Seattle-Tacoma International Airport (STIA) covering the period July 1, 1998 through June 30, 1999. Documents NPDES stormwater sampling results across STIA storm drainage subbasins including grab and composite samples for total petroleum hydrocarbons (TPH), fecal coliforms, suspended solids (TSS), turbidity, biochemical oxygen demand (BOD5),