Tagsoil(64)

This August 2025 draft report by Haley & Aldrich, Inc., prepared for the Port of Seattle, presents geotechnical and hydrogeological findings for the Industrial Wastewater Treatment Plant (IWTP) Above Ground Basin (AGB) site at Seattle-Tacoma International Airport. The report covers subsurface soil and groundwater conditions, seismic hazard assessments, and engineering design recommendations for elements such as slopes, embankments, and excavation support. It serves as a technical reference to guide construction and infrastructure decisions at the airport site.

The King Conservation District (KCD) offers a Soil Nutrient Testing Program for landowners in King County, Washington, providing up to five free soil tests per address to help residents manage fertilizer use, protect water quality, and optimize plant growth. Samples are sent to a certified lab to analyze key nutrients, pH, and organic matter, with results typically returned within three weeks. Additional tests beyond the free allotment are available for $30 each.

This Washington State University Cooperative Extension factsheet explains the risks of heavy metals such as lead, cadmium, and arsenic in garden soils, with a focus on the greater Seattle-Tacoma region. It identifies locations most likely to have contamination, including sites near old painted buildings, heavily traveled roads, and areas affected by the former Tacoma smelter. The factsheet offers practical gardening tips to reduce exposure, such as growing fruiting crops, adding organic matter, liming soil, and washing produce thoroughly.

This 2020 environmental study examines groundwater and soil quality at and around Seattle-Tacoma International Airport from 1997 to 2019, tracking changes in contamination levels and evaluating whether they stem from airport operations, other pollution sources, or stormwater runoff. The report draws on data from the Port of Seattle, surrounding cities, and state environmental agencies to assess the effectiveness of the airport's cleanup efforts and identify any contamination that may have spread beyond airport property. The underlying geology—dense glacial till soils—generally slows the movement of contaminants through the ground in the area.

Handwritten notes dated 2/13 document a phone call at 9:56 AM regarding fill and runway notification related to a sales tax exemption, referencing figures of 1,500 and 10/5/2000. The notes also address Reports of Remedial Action concerning tax exemption copies, a Bellevue Site with TPH contamination, and 1,500 tons of suspected contaminated soils transported to three RW sites. A 4:00 PM follow-up call with Pete confirmed that soil was removed from three RW project areas for treatment (ISR) shortly after it was placed.