Jefferson Avenue Site

Environmental cleanup is complete at the site and no further cleanup actions are needed. Ecology is in the process of removing the environmental covenant from the site. 

Ecology held a comment period from June 3 to July 6, 2021, and asked the public to comment on the proposal to remove Environmental Covenant Number 201312260516 from the site. We received no public comments during the comment period. 

The Jefferson Avenue Site is located at 2112-2122 Jefferson Avenue in Tacoma. The area was used for houses, a gas station, automobile sales and repair, welding, and steel fabrication. The structures were removed in 2002, leaving the parcels vacant.

In 2017, the City of Tacoma sold the property, which is being developed for housing and offices. 

In 1995, three 2,000-gallon and one 10,000-gallon underground storage tanks (USTs) and the associated piping were removed. Approximately 600 to 800 cubic yards of petroleum-contaminated soil were stockpiled on the site. About two years later, testing of the stockpile indicated that petroleum hydrocarbons were no longer detected. 

In 2002, one 500-gallon waste oil UST, one 1,800-gallon gasoline UST and associated piping, and a hydraulic hoist were removed. Approximately 175 cubic yards of gasoline-contaminated soil were removed from the area where the USTs were located and disposed of off-site. After soil removal, there was no further soil contamination above state cleanup levels in that area.  Groundwater samples indicated contamination with gasoline and benzene concentrations above state cleanup levels.

Soil collected from the hoist excavation was contaminated with petroleum and about 220 cubic yards of soil were removed and disposed of off-site. Water collected from the excavation showed diesel- and oil-range petroleum hydrocarbons were above state cleanup levels.

Six groundwater monitoring wells were installed to determine conditions at the site due to the known presence of gasoline- and diesel-range hydrocarbons in groundwater from leaks from the USTs and the hoist. Between 2004 and 2005, diesel-range hydrocarbons were detected in one well. But continued monitoring showed petroleum contamination decreased to below cleanup levels.

A brownfields assessment was conducted in 2012 to determine if any USTs and contamination remained at the site. Results showed the USTs had been removed and soil conditions were below the cleanup standard. One monitoring well detected arsenic above the cleanup level in groundwater.

Shallow groundwater in the area of the site is not typically used for drinking water. Ecology decided that institutional controls could be used to address the arsenic that was found in groundwater in one area. 

An environmental covenant was recorded for the site in 2013 because arsenic contamination was detected in groundwater after cleanup. Ecology issued a No Further Action (NFA) letter in 2014. 

Arsenic in groundwater was measured again in 2019-2020. The amount of arsenic had decreased over time, but remains slightly above the cleanup level in one well. The amount is low and it is below the state background level. Groundwater will not be used for drinking because the city supplies drinking water to the Site.

In 2021, it was Ecology’s opinion that the covenant was no longer required, and the owner requested it be removed from the property.