According to allegations in the complaint, Clean Rock accepted 66 to 77 tons of oil-contaminated sludge known as "tank bottoms" from a tank-cleaning operation being performed on an oil tank at Mack Trucks.
The sludge, which contained waste-cutting oil and other oil products, was sent to the 107 Oak Ridge Place facility from Aug. 20 to Aug. 26, according to the complaint.
The complaint alleges that the company mixed the sludge with cement and kiln dust and dumped it onto a large pile of asphalt millings.
"It's kind of like mixing a gigantic cake batter," Banks said.
Clean Rock was placing the contaminated soil in a pug mill, where it was mixed, and released it from the facility as clean soil, according to the complaint.
Susie Smith, who lives next to Clean Rock, said she called the Washington County Health Department.
"We could smell this cutting oil," she said. "It was in my house, which is some distance away."
Timothy Henderson, an attorney for Clean Rock, said the firm intends to file a request for a hearing before an administrative law judge to contest the complaint. He said the request protects the company's right to a hearing if it cannot settle the dispute with the department.
Henderson said the company has filed for a modification of its permit, but does not concede any wrongdoing. He said the firm wants to clarify the situation.
"From the facts I have, the agency was premature," Henderson said.
Banks said oil-contaminated soil poses a potential threat to ground water, although he added that the department's complaint does not contend the soil damaged the environment.