The Arizona Department of Environmental Quality declared Wednesday that one of its 36 superfund sites is safe, nearly 15 years and $12 million after the project began.
The 10-acre parcel in central Phoenix has become the first superfund site to be removed from the state’s Water Quality Assurance Revolving Fund registry.
“This is a huge day in the history of the Arizona Department of Environmental Quality,” the agency’s director, Henry Darwin, said in a press release. ADEQ had major challenges with the site, Darwin added, which added to the cost of cleanup and the time it took.
The site at the southwest corner of East Buckeye Road and South Fifth Street, within walking distance of Chase Field, made it onto the registry in June 1999 after ADEQ determined that levels of cadmium, chromium, lead, and polychlorinated biphenyls exceeded state and federal safety standards.
The site’s former owner, National Metals Co., used the land to shred automobiles and then to bury the shredded material in a pit on-site, said Danita Hardy, ADEQ project manager, who has managed the site for the last six years.
“Back then doing that was perfectly legal,” said Hardy. “They didn’t have regulations.”
The shredded material, also called auto fluff, was buried as far down as 20 feet, Hardy said. ADEQ dug out only the first 10 feet of auto fluff and soil, over 6,000 tons of hazardous waste. But after sealing the site with a pressurized soil cap, it’s now safe, she added.
Water contamination was not ADEQ’s main concern, though it did drill three wells on site to monitor any contamination, Hardy said. All three wells were dry at last check and have been dry since 2003, she noted.
ADEQ’s main concerns have been soil and air contamination, she said. People on the property could have been harmed by coming into contact with the soil. Air contamination is also a possibility if the hazardous materials somehow became airborne. That is why the cap was placed on the site and why its integrity is important to future safety.
The site was purchased in 2006 by Harrison Properties. In 2010 Harrison placed a two-foot deep layer of crushed concrete material on top of the soil cap. ADEQ approved the work and it is continuing to evaluate any impact to the cap’s integrity.
More information on the site is located at the following link: www.azdeq.gov/environ/waste/sps/download/phoenix/ewf.pdf