shawna.morrison@roanoke.com 981-3349

A metal-finishing shop in downtown Roanoke is under investigation by the U.S. Environmental Protection Agency, officials said Thursday.

Paul Truntich, the city's environmental administrator, confirmed that Advance Metal Finishing at 523 Norfolk Ave. S.W. is under scrutiny but said he could not disclose exactly why the EPA was conducting the investigation.

Special agents with the EPA's Criminal Investigation Division spent Thursday looking into the sanitary sewer lines through manholes on Norfolk Avenue near its intersection with Fifth Street Southwest.

Susan Helbert, EPA assistant special agent in charge, said the group was investigating a complaint but would not say who made the complaint or exactly what the EPA was searching for.

"We get involved when we believe it's a serious concern for the environment," Helbert said. But, she said, there was no reason to believe there were any health or safety concerns.

Helbert said the EPA was expected to wrap up its search late Thursday.

Truntich said the investigation had been going on longer than the one day, but he wouldn't say how long.

U.S. Attorney John Brownlee said the investigation was a pending matter and that he couldn't comment on it.

Metal finishing is the process of changing the surface of an object to improve its appearance or durability. There are many ways to finish metal, including electroplating, organic coating, powder coating, anodizing, electropolishing and phosphate coating. It can be done by spray applications, chemical baths, electrodeposition and other mechanical applications.

Electroplating, a common finishing method, involves applying a thin metal coating by using an electrochemical reaction that pulls metal particles from a sodium solution and binds them to their host. Parts can be plated with zinc, nickel, brass, copper, silver or black oxide.

A Virginia Waste Minimization Program fact sheet on waste reduction for metal finishers posted on the EPA's Web site says typical wastes generated are industrial wastewater and treatment residues, spent plating baths and process baths, spent cleaners, and waste solvents and oils.