The state Department of Environmental Conservation released cleanup plans late last week for two Niagara Falls hazardous waste sites: Frontier Chemical at 47th Street and Royal Avenue, and Tract II on Highland Avenue.
In both cases, the plans are similar to those proposed at recent public meetings, except for the discovery of radioactive contamination at Tract II, according to Greg Sutton, DEC regional hazardous waste remediation engineer.
The 9-acre Frontier Chemical site also will be scanned for radioactive hot spots.
The DEC requires the scans to make sure there's no interference with plans to excavate and treat contaminated soil on-site. A cover of clean dirt at least a foot thick will be required where the site isn't paved or built over.
Sutton said the thermal cleaning of the soil is estimated to cost $7.1 million and will be paid for by a group of responsible parties that dumped hazardous waste at Frontier from 1974 to 1992.
Frontier had a permit for hazardous waste disposal until the DEC shut the operation down.
"There's 5,300 potentially responsible parties," Sutton said. "We have a record of everyone who dumped there."
At Tract II, a former owner, Honeywell International, has agreed to pay for the estimated $6 million cleanup.
Contaminated soil is to be mixed with cement. The solidified mass will be covered with clean dirt or paved over for redevelopment.
Hazardous waste considered concentrated enough to leach through the ground will be removed to a disposal site, the DEC's plan says.
The city has agreed to sell the 18-acre tract to developer Jon Williams for $1. Williams plans to create a park, a retail development and an incubator for light industry.
Tract II was used as a production site by several businesses from 1903 to 1970.