EPA working at former BA landfill found potentially dangerous levels of radioactivity

Workers are placing two 6-inch layers of compacted clay on the Wagoner County parcel, located on seven acres of vacant land south of Kenosha Street and east of South 219th East Avenue, said David Robertson, a on-site coordinator with United States Environmental Protection Agency Region Six.

The primary concern is thorium-232 and its “decay chain” parent, radium-228; the latter decays into radon gas, a carcinogen.

“The primary concern at the site is the presence of Th-232 contaminated soil above a site-specific action level, impacting potential future workers at the site and the surrounding population,” a memo reads. from the EPA in August.

While officials have known about the presence of radioactive material at the site for years, the amount discovered recently came as a surprise.

Robertson said the agency plans to remove the top 6 inches of material it believes to be contaminated. But after excavation began, they determined that the top foot of the floor was largely free of contamination, Robertson said.

“Then there was about 4 feet of solid material that had a lot of thorium-232 in it,” Robertson said in an interview.

“We found there was more material than we could reasonably have available,” said Robertson, who described the material as blue-gray in appearance and color concrete.

“It looks like industrial waste,” Robertson said. The EPA’s enforcement unit is trying to trace the source of the material, which was believed to have been left there while the property was in use as a municipal landfill, Robertson said.

Robertson said the current owner, a limited liability company, discovered the excessive radioactivity after buying the property to redevelop.

Workers have been at the site since early October, Robertson said. The project is expected to be completed by mid-December unless rain delays, he said.

Once the cap is placed on the ground, it will be fenced off and seeded, Robertson said. The property will then need to be mowed regularly and monitored for erosion, he said.

The parcel also has a deed restriction that requires approval from the Oklahoma Department of Environmental Quality before it can be developed.

Details of past use of the property are conflicting.

The City of Broken Arrow licensed the property in 1973 for use as a sanitary landfill. The permit was closed in 1976, according to the EPA. While records indicated the property may never have been used for a landfill, Robertson said workers digging the land found evidence it was used as such.

Before being cleared for landfill, the parcel was part of an 80-acre parcel used to strip coal from the mine in the 1920s and 1930s, according to the EPA.

The leaflet came under government scrutiny when it became part of the Oklahoma Department of Environmental Quality’s Brownfield program sometime after 2008, according to EPA records.