The state Department of Natural Resources added Friday to a list of environmental concerns surrounding Madison-Kipp Corp. on the city’s East Side. The DNR issued a notice of violation alleging the manufacturing facility failed to report PCB contamination it has known could exist at its site for nearly six years.

Earlier this year, contractors excavated soil to deal with contamination from chlorinated solvents at the facility at 201 Waubesa St. The additional PCB contaminants were identified by a disposal facility in Michigan where the soil was shipped, said Mark Giesfeldt, director of DNR’s remediation and redevelopment bureau.

Documents DNR requested from Madison Kipp revealed the company learned in 2006 that spent oil potentially contaminated with PCBs had been used as a dust suppressant on parking lots at the property, Giesfeldt said.

PCBs were banned because they were found to cause neurological problems in humans.

"The concern is that they had information back in 2006 that there was likely PCBs at the site, and they didn’t tell us about it while we were dealing with all this other contamination," Giesfeldt said. "That failure to report is a serious violation in dealing with properly responding and cleaning up contaminated sites in our state."

Much of the attention on pollution from the plant has focused on potentially carcinogenic vapors from tetrachloroethylene, an industrial solvent used at Kipp until 1987 that has seeped into adjacent homes. City water and health officials also are monitoring a contaminant plume that could affect groundwater.

A spokesman for Madison Kipp could not be reached Friday.