Ward Transformer plan poses dioxin risk to Raleigh

There was a worrisome story in this morning's New & Observer, which reported that the companies responsible for cleaning up PCB contamination at Raleigh's Ward Transformer Superfund site want to incinerate the waste there instead of shipping it away for treatment. The problem is, incineration would result in the release of additional toxic chemicals to the environment.

Ward Transformer is located at 6852 Mt. Herman Road, in a fast-developing area of northwest Raleigh near the junction of Glenwood Avenue and Northern Wake Expressway. The site lies about a mile east of the booming Brier Creek development, which includes luxury homes, condos, apartments, a retail shopping center, and Brier Creek Elementary School.

The incineration method the companies want to use is known as direct-fired thermal desorption. N&O reporter Wade Rawlins describes the process like this:

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.

Sounds nifty, but there's a catch: The process results in emissions of public health concern, according to a 2002 review of thermal treatment technologies conducted by the U.S. Agency for Toxic Substances and Disease Registry. Those emissions include toxic chemicals known as "products of incomplete combustion" or PICs (which include polycyclic aromatic hydrocarbons), dioxins and furans, and metals. Among the metals that have been detected in the soil at the Ward site are arsenic, chromium, copper, lead, manganese, and zinc. Some of those are cause for worry when it comes to incineration, ATSDR says:

Arsenic, beryllium, cadmium, and chromium are metals sometimes found in wastes and stack emissions that because of their carcinogenicity could be of health concern.

On the potential for additional dioxin contamination (dioxins are already among the site's contaminants), the story quotes Jim Sherman, industrial toxicologist and member of the citizens task force monitoring the Ward cleanup:

"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 what Sherman doesn't say in the story -- what no one says -- is that cancer is not the only health concern related to dioxin exposure.

Dioxins bioaccumulate -- that is, they build up in bodies over time. Humans are exposed to them primarily by eating high on the food chain -- things like beef, pork, dairy products and fish -- thereby ingesting what's accumulated in the creatures' bodies. Environmental dioxin contamination, as of soils in contaminated yards and gardens, is an additional source of exposure. The EPA itself acknowledges that dioxin is likely to cause cancer. But the documented health effects of dioxin exposure in humans include a host of other problems, including thyroid disorders, immune system impairment, endometriosis, birth defects, and diabetes. Meanwhile, studies of lab animals exposed to dioxin have found increased rates of liver, lung and thyroid cancer.

Is there a potential for public exposure at Ward? Obviously. Tests of waters downstream from the site -- which is located along a stream in a previously undeveloped wetland -- have found widespread PCB contamination. Consequently, the state has issued fish consumption advisories for Little Brier Creek downstream of Brier Creek Parkway, the creek's tributaries, Brier Creek Reservoir, Lake Crabtree, and Crabtree Creek. Once a popular public fishing spot, Lake Crabtree has been operating under a catch-and-release policy since November 2005 because of the high levels of PCB pollution in the fish.

The companies considering the incineration option -- including Raleigh-based Progress Energy -- are expected to come up with their final workplan in the "next few weeks," says EPA spokesperson Laura Niles. But at this point, it's still not too late for citizens concerned about onsite incineration to weigh in. Though the workplan is not subject to a formal comment process, Niles says people may share their thoughts with her agency.

"If there's great public concern, we'll address that," she tells Raleigh Eco News.

People may contact either Remedial Project Manager Luis Flores at flores.luis@epa.gov or Community Involvement Coordinator Angela Miller at miller.angela@epa.gov, says Niles. They can also be reached on EPA's toll-free line at 800-241-1754.