After more than a decade of cleanup efforts and testing, the Environmental Protection Agency (EPA) is ready to essentially shut down a Superfund site in south Minneapolis where industrial arsenic had contaminated the soil surrounding about 600 homes.

The East Phillips neighborhood site, near Hiawatha Avenue and E. 28th Street, has been on the EPA's list of priorities under its Superfund program for years after extremely high arsenic levels were found in many of the yards surrounding an old rail line.

Remediation efforts have been almost entirely finished since 2011, when the EPA completed a $25 million project to dig up and replace most of the contaminated soil. A scheduled review conducted in April found that the soil poses no threat to humans or the environment and that it's time to take the vast majority of the neighborhood off the priority list.

"The remedy is functioning as intended," the review said.

The EPA plans to keep just nine properties on the cleanup list, where homeowners have refused to allow soil tests. The agency will continue conducting regular reviews until all nine are tested and remediated.

With the soil safe, there's really no reason to keep the rest of the neighborhood on the list, said Cathy Villas-Horns, supervisor of the incident response unit for the Minnesota Department of Agriculture.

"Except for those nine properties, the cleanup has been completed," Villas-Horns said.

Regulators believe that wind carried the arsenic into the neighborhood over the course of three decades from a site where the now-defunct Reade Manufacturing Co. had been storing, producing and dumping an arsenic-based insecticide from the 1930s until the 1960s.

In the early and mid-2000s, the EPA and Agriculture Department tested the soil of more than 3,500 houses, day-care centers and parks, as well as a cemetery in the area, finding unsafe levels of arsenic in more than 600 properties. By 2011, the two agencies had spent more than $25 million, largely from federal economic stimulus money, tearing out the yards and removing at least 1 foot of topsoil in each of the contaminated properties. They poured in clean topsoil and reseeded each lawn with grass.

There were roughly 30 holdouts in 2011 — properties where owners refused to grant permission to test their lawns. Over the past eight years, the EPA has whittled that number down to the nine who continue to deny permission.

Minnesota has 25 sites on the EPA Superfund priority list, which serves as a roster of contaminated areas that are eligible for federal cleanup funding. It primarily helps EPA managers decide where to focus limited funds. The site's removal from the Superfund list "does not in any way alter EPA's right to take enforcement actions, as appropriate," the agency said in a statement.

If more contaminants are found, the EPA could place the area back on the list.

The state keeps its own list of cleanup priorities for the Superfund sites in Minnesota, including the former Reade Manufacturing property itself, at 2800 Hiawatha Av. The EPA decision will not affect the state's ongoing groundwater cleanup and monitoring efforts at that property, which is a now a business center, Villas-Horns said.

Neighbors still worry

Some residents expressed concern Wednesday about potential consequences of taking the neighborhood off the Superfund list, saying the area is far from clean.

"If anything deserved the designation of a Superfund site, this neighborhood did and still does," said Brad Pass of the East Phillips Improvement Coalition.

Properties in the area, such as the former Roof Depot immediately west of the Reade site, are slated for redevelopment, Pass said. But the building and asphalt parking lots may have been built on top of potentially polluted soil, trapping contaminants there for years.

Once those structures are torn down, Pass said, he's worried there may be arsenic underneath that is once again blown into the neighborhood.

"Although they have remediated certain lots, this is going to open up tremendous potential for spreading this arsenic all over the place," Pass said.

Greg Stanley • 612-673-4882