CORRECTION

A story Tuesday on the City & State front about the cleanup at the Ward Transformer property in Wake County referred to Dana Yeganian with a pronoun of the wrong gender. Yeganian is a woman.

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The companies responsible for cleaning up the contaminated Ward Transformer industrial property are considering treating the soil and incinerating the toxic PCBs on the site. The method will leave a residue of other toxic chemicals in the community -- a point that some say merits further discussion.

A portable unit with an afterburner is the first choice of three disposal methods under review for decontaminating 100,000 tons of polluted soil at the Superfund site near Raleigh-Durham International Airport.

"That is the one that we are leaning toward and pursuing the most," said Dana Yeganian, a spokeswoman for Raleigh utility Progress Energy, one of the companies involved in the cleanup. He said the unit was available for prompt use.

The contamination -- primarily polychlorinated biphenyls -- came from spills of oil used in electrical transformers in the 1960s and '70s. Ward Transformer built and reconditioned transformers at the site from 1964 until the end of 2005. The company's methods of handling PCB-laced oil drained from the transformers led to widespread contamination of the site and nearby creeks, causing the site to be designated a high-priority cleanup under the federal government's Superfund Program.

A settlement approved by the U.S. Department of Justice last fall calls for Ward and its customers, including Progress Energy, to pay for cleaning up the 11 contaminated acres.

The companies are focusing on a cleanup method called direct-fired thermal desorption, in which chemicals are heated and turned to gases. Contaminated soil is dug up and heated in a giant industrial dryer, similar to a clothes dryer, causing the pollutants to vaporize. In a second step, the PCB vapors are destroyed in an afterburner and the gases scrubbed and vented through a stack.

Thomas F. McGowan, president of TMTS Associates of Atlanta, an engineering consultant on the project, said by that method Ward's estimated 100,000 tons of contaminated soil could be cleaned up in less than five months.

McGowan said the equipment would comply with federal emissions limits.

Jim Sherman, an industrial toxicologist and member of the citizens task force that has monitored the Ward cleanup, said the proposed disposal method would create a new source of dioxin pollution. Dioxins are formed as a result of combustion processes such as commercial or municipal waste incineration and from burning fuels. Some studies have suggested a higher risk of cancer for people exposed to higher levels of dioxins.

"There is absolutely no doubt there will be dioxins created, and those dioxins will be distributed in the community," Sherman said. "The quantity of dioxins emitted are not likely to pose a cancer risk great enough to pose a real health concern."

But Sherman said the prospect of an incinerator emitting dioxins had received little debate locally.

"It's often unacceptable to communities to have new sources of dioxin emissions," he said.

The companies received bids on three disposal methods. Progress Energy declined to release the bids until a contract is signed.

Yeganian said digging up the contaminated soil and hauling it away for disposal would cost about $5 million more than treating it on site. A third option involves heating the soil to vaporize the PCBs, then turning the vapor into liquid and hauling it off. It was the least expensive option, Yeganian said, but could not be done as quickly.

Jim Warren, executive director of the N.C. Waste Awareness and Reduction Network, an advocacy group, served on a citizen task force that oversaw the cleanup of a landfill containing PCBs in Warren County. Warren said that the Warren County task force rejected the disposal method that the companies are favoring for the Triangle.

"That's a toxic waste incinerator on site," Warren said. "We rejected on-site incineration as too dangerous. The worst thing to do is convert toxic PCBs into even more toxic dioxins and furans."

Officials with the Environmental Protection Agency have said they were comfortable with all the cleanup methods under consideration.

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