TagArsenic(16)

Laura Hartema of Friends of Des Moines Creek presented concerns about the proposed Des Moines Creek Business Park West Development (File #LUA2022-0044) in October 2024, highlighting significant environmental impacts including the removal of over 500 trees, filling of wetlands and streams, and more than 30 acres of site disturbance. The presentation compared 1936 and 2023 aerial photos showing the area remains largely forested, and raised issues such as arsenic in soils, stormwater management concerns, and negative effects on neighboring residential properties. The group argues the project requires more thorough environmental review to demonstrate it will not cause significant harm to critical natural areas and the surrounding community.

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 technical document describes the background water chemistry and modeling assumptions used to estimate how metals move through soil and groundwater at contaminated sites. It outlines key simplifications in the MINTEQ geochemical model, including the assumption of chemical equilibrium and the exclusion of redox potential, and presents soil-sorption values (Kd) for various metals such as arsenic, chromium, and cadmium that vary with soil pH. The results show that metal mobility is most strongly influenced by pH levels in the subsurface environment.

A soil contamination study by Washington State's Department of Ecology and Public Health – Seattle & King County found elevated levels of arsenic and lead in southern King County soils, linked primarily to the former Asarco smelter in Ruston. Contamination levels were highest near the smelter and on Vashon and Maury Islands, with concentrations decreasing further from the source and following prevailing wind patterns. While the findings are a concern rather than an emergency, officials stress that the study reflects regional trends only and cannot predict contamination levels at individual properties.

Water quality criteria spreadsheet (CRITERIA.XLS) for the SeaTac Third Runway Embankment Project, prepared by Chung Ki Yee, run date 2/20/02, created by D. Nunnallee (rev. 1-92) with last revision 3/00. Lists fresh and marine acute and chronic water quality criteria (in ug/L) for metals including antimony (inorganic), arsenic (dissolved), beryllium, cadmium, chromium (TRI and HEX),