Commencement Bay, Near Shore/Tide Flats covers 12 square miles of shallow water, shoreline, and industrial land near Tacoma, Washington. It was added to the Superfund National Priorities List in 1983 after widespread contamination was found in water, sediments, and upland areas. Remedial work started in 1989 and is still ongoing, with construction not yet complete across the full site.
Contaminants include heavy metals such as arsenic, lead, cadmium, copper, mercury, and zinc, along with organic chemicals including benzene, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and tetrachloroethene. These substances have been found in sediment, groundwater, surface water, soil, and fish tissue. People face health risks from eating contaminated seafood, direct contact with contaminated soil and water, and inhaling contaminated particles. Aquatic life is also at risk from sediment and surface water contamination. Human exposure is not under control, meaning unsafe contamination levels have been detected and people could still be exposed.
EPA has divided the site into seven operable units. Major sediment dredging and capping has been completed in the Hylebos, Sitcum, St. Paul, Middle, and Thea Foss Waterways. At the former Asarco Tacoma Smelter, Phase I remediation finished in 2015, with remaining cap construction and related work estimated to wrap up by late 2028. In the Ruston and North Tacoma area, EPA sampled 3,570 properties and cleaned up 2,436 with the worst arsenic and lead contamination. The Washington Department of Ecology has been conducting additional voluntary cleanups in a broader study area since 2013. At the Tacoma Tar Pits, roughly 185,170 cubic yards of contaminated material was excavated and stabilized in 2002, and a groundwater treatment system was installed to prevent off-site migration. Cleanup levels for metals, cancer-causing PAHs, and PCBs have been achieved at the tar pits. The most recent five-year review was completed in April 2025.
Redevelopment tied to the cleanup has brought real economic benefit. The Thea Foss Waterway now hosts a waterfront park, restaurants, condominiums, and the Museum of Glass. The former Asarco smelter site is being redeveloped as Point Ruston, a mixed commercial and residential area that also includes the 23-acre Dune Peninsula Park, opened in July 2019. As of December 2024, on-site businesses numbered 713, employed 16,439 people, and generated about 4.3 billion dollars in annual sales.
Community members can get updates by joining EPA's mailing list and email listserv. A recording from EPA's March 2024 community meeting in Ruston is available. Residents can contact the Community Involvement Coordinator or the Remedial Project Manager with questions about the five-year review or the site overall.
