EPA asks for expansion of Ameren PCB investigations
U.S. Environmental Protection Agency Region 5 has asked that Ameren Corporation and its subsidiaries expand their investigation into PCB-contaminated liquids found in natural gas distribution systems in Alton and East St. Louis, Ill.
Ameren, under EPA and Illinois EPA oversight, recently inspected the gas supply equipment at Alton Middle School and 12 residences in East St. Louis. The gas equipment in the school did not contain PCBs. However, three liquid collection points outside the school were found to have liquids with PCBs and Ameren removed them. Low levels of PCBs were discovered in liquids in gas meters outside three of the residences in East St. Louis. Ameren replaced the meters and cleaned up the soil beneath them.
PCBs were used historically in some natural gas distribution equipment, typically as a compressor lubricant or valve sealant. If sources of PCBs are found, EPA will require that they be removed.
EPA has specified that Ameren revise a draft inspection plan submitted to EPA for buildings where the PCBs were previously found. EPA also asked for Ameren to use specific procedures for sample collection, analysis and further investigation, if warranted.
EPA anticipates a response from Ameren in the next few days. Ameren's proposed approach will be reviewed by EPA and partner agencies including Illinois EPA and the Illinois Attorney General's office.
The investigation is an outgrowth of Nicor's recent disclosure to EPA that PCB liquids were found in a Park Ridge, Ill., gas distribution system. EPA requested that other Illinois natural gas utilities review their records for similar incidents. As a result, Ameren recently disclosed that they found liquids in their systems in certain buildings in Alton and East St. Louis during the 1980s-which were then re-inspected by the agencies and Ameren.
PCBs are mixtures of synthetic chemicals ranging from oily liquids to waxy solids. Because of evidence that PCBs persist in the environment and cause harmful effects, domestic manufacture of commercial mixtures stopped in 1977 and existing PCBs continue to be used. EPA data indicates that PCBs are probably cancer-causing substances.
For more information on the health effects, regulations, and cleanup of PCBs, go to www.epa.gov/pcb
This article originally appeared in the 08/01/2007 issue of Environmental Protection.