PCB cleanup plans revealed

Federal officials detail the blueprint for decontaminating the Ward Transformer site

Federal environmental officials on Tuesday unveiled the plan to clean up the contaminated Ward Transformer industrial site near Raleigh-Durham International Airport.

The plan calls for the contractor to dig up about 100,000 tons of contaminated soil from the Ward site, starting in early summer. About a third of the soil with low levels of contamination will be trucked off to a private landfill in Roxboro, and about 67,000 tons of the more highly polluted soil will be decontaminated on site, then placed back in the ground.

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 calls for Ward and its former industrial customers, including Progress Energy, to pay for cleaning up the 11 contaminated acres. The estimated cost is $10 million.

"The whole project is expected to take about 13 months," said Gary Collison of Golder Associates Inc., a project consultant based in Atlanta. Collison said workers expect to be on site in late May or June, once the U.S. Environmental Protection Agency gives final approval.

The cleanup method involves a process called thermal desorption, in which chemicals are heated and turned to gases. The highly 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.

Raleigh officials have asked the contractors to test the decontaminated soil to ensure it does not contain unsafe levels of dioxins, toxic chemicals that can be formed during the combustion of PCBs.

Tim Briggs, project manager for Compass Environmental Inc., which will operate the desorption equipment, said the firm will do additional testing for dioxins in treated soil initially to ensure the process is working properly.

An unanswered question is whether contamination downstream from the Ward industrial site such as in Lake Crabtree County Park will be cleaned up. EPA officials are doing a separate feasibility study of cleanup alternatives for the area that includes Lake Crabtree County Park and Crabtree Creek. That will be released in September.

Luis Flores, EPA's project manager, said tests picked up minute levels of PCBs in sediment in the bottom of Lake Crabtree but none in soil along the shoreline or farther downstream in Crabtree Creek. However, fish from Lake Crabtree and Crabtree Creek have shown unsafe levels of PCBs, prompting the park and state health officials to post warnings about consuming the fish.