Carter Carburetor Citizens Advocacy Group

NEWS

March 31, 2011

Citizens Question Unproven Cleanup Technology for Carter Carburetor Toxic Site

(ST. LOUIS, MO)-Purveyors of a proprietary technology who presented at a community meeting sponsored by the Environmental Protection Agency faced tough questions from local citizens Tuesday. Citizens grilled company representatives from TerraTherm, a spinoff of Shell Oil, about their In Situ Thermal Desorption (ISTD) technology that is being proposed for use at the Carter Carburetor Superfund site at St. Louis Ave. and Grand Ave. in north St. Louis.

The EPA is considering permitting the technology to be used to treat two of the most contaminated areas of the site. One area is contaminated with Trichloroethylene, a chlorinated solvent, from leaky above ground storage tanks. The other area is contaminated with polychlorinated biphenyls, or PCB’s, a cancer causing chemical once used in electrical transformers that were disassembled at the former Diecast building on the site (the Diecast building has since been demolished). The PCB contamination at Carter Carburetor extends down to bedrock in some places and contaminates an area encompassing about 30,000 cubic yards of soil. It is found in the soil in alarmingly high concentrations (more than 200,000 parts per million). Portions of the building also contain PCB contamination.

It is the widespread extent of the contamination, the concentration of the PCB’s,  and the potential for PCB’s to form dioxins, some of the most potent cancer-causing chemicals known to man and the famous contaminant from Times Beach, that have sparked community concerns.

The ISTD technology aims to heat up the ground using “thermal wells” or holes drilled to the depth of the contamination and heated with electricity to 635 degrees F. At this temperature, Terratherm expects the contaminants to volatize.  A piping and vacuum system then draws the vapors into an emissions control and filtering system.  The surface of the ground is insulated and sealed in order to allow the vacuum to function.

“Terratherm has not demonstrated that this technology can treat PCB contamination at this scale,” said Romona Taylor Williams, Executive Director of the Metropolitan St. Louis Coalition for Inclusion and Equity and a member of the Carter Carburetor Citizens Advocacy Group. “We are not about to risk the health of our children on an approach that is not proven to be effective and safe.”

Representatives of the Carter Carburetor Citizens Advocacy Group questioned the EPA’s analysis of this technology earlier this year when it was first proposed, noting that children did not factor into the risk assessment and the proposed plan for the cleanup of Carter Carburetor, despite its proximity to the Herbert Hoover Boys and Girls Club and residences.  An analysis of the proposed plan the Environmental Protection Agency is considering for the site found that youth were not part of the risk assessment equations used to determine how much of the cancer-causing contaminants to leave at the site.

“Because heating PCB’s can lead to the formation of dioxins, the on site heat-treatment plan is questionable,” said Kathleen Logan Smith, Executive Director of the Missouri Coalition for the Environment. “PCBs are not very volatile, which adds to the uncertainty.  This, coupled with a flawed risk assessment that okays a higher cancer risk for area children, suggests to us that ISTD won’t be a clean clean up.”

Logan Smith added that ISTD has more potential for effectiveness on the TCE contamination because of the lower temperatures needed, the smaller extent of contamination, and the volatility of the material.

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