The Nineteenth Avenue Landfill covers 213 acres in Phoenix, Arizona, and holds about nine million cubic yards of waste. The site entered the Superfund program after an initial assessment in October 1979, was added to the National Priorities List in September 1983, and was deleted from that list in September 2006 after cleanup goals were met. It is also known as the 19th Avenue Landfill and the Salt River Landfill.
Improper waste management practices contaminated soil and groundwater at the site. Contaminants of concern include metals in groundwater such as antimony, arsenic, barium, beryllium, nickel, thallium, and pentachlorophenol. Volatile organic compounds including toluene, xylene, and naphthalene were found in solid waste and groundwater. Methane is present in landfill gas and solid waste.
The City of Phoenix led the cleanup. Short-term actions in 1981 included covering the site with sand, gravel, and stones, constructing berms and a fence to limit access, and installing groundwater monitoring wells. The long-term remedy consists of an engineered cap over the landfill waste, a methane gas collection and flaring system to prevent off-site gas migration, and levees along the Salt River to prevent flooding and waste washout. Remedy construction finished in 1996, and the gas collection system began operating in 1997, with overall construction completed in February 1998. The City of Phoenix continues to maintain the cap and gas collection system and monitors groundwater. The landfill has not impacted off-site groundwater quality.
The most recent five-year review, completed by EPA in August 2025, found that cleanup actions are in accordance with the selected remedy and continue to protect human health and the environment. The review characterized the cleanup as short-term protective. Human exposure at the site is currently under control, all cleanup goals for current and reasonably anticipated future land uses have been achieved, and required land-use restrictions are in place. The site achieved ready-for-anticipated-reuse status in October 2007.
Community members can review site records at the EPA Superfund Records Center at 75 Hawthorne Street, 3rd Floor, San Francisco (415-947-8717), or at the Arizona Department of Environmental Quality Records Management Center at 1110 West Washington Street in Phoenix. For questions, residents can contact the EPA Community Involvement Coordinator, the EPA Remedial Project Manager, the Arizona Department of Environmental Quality Project Manager, or the City of Phoenix Engineering Supervisor.
