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Archive - Hazardous Waste Cleanup: PCB and Gas Pipelines Illinois

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  • In May 2007, Nicor gas company informed EPA that four homes in Park Ridge were affected by contaminated liquid in gas lines.
  • Nicor tested 140 additional homes in Park Ridge to ensure that the problem is an isolated one.
  • Nicor also tested 2 school utility rooms and a church with a day-care center; low levels of PCBs were found in all 3. EPA has carried out follow up sampling to ensure that students, faculty and staff at those places are not exposed to PCBs. EPA carried out wipe sampling and air testing at 6 additional schools of District 64, which serves Park Ridge and Niles.

Nicor first learned of the problem and company officials informed EPA in June that contaminated liquid in its natural gas lines affected the Park Ridge homes. Nicor did work inside two homes and worked on the gas meters at the other two homes.

In response to requests for information from other gas companies serving Illinois, EPA learned that a school in Alton and at least 10 homes in East St. Louis were contaminated with PCB. The school and homes are served by Ameren. No PCBs were detected in the Alton school at a follow up inspection and no homes were found with detectable levels of PCBs in East St. Louis. EPA is working with Ameren for expanded inspections using a protocol similar to that used for the Nicor inspections.

Liquid in gas pipelines is rare. It can occur when gas passes through regulator stations in the pipeline, and some of the heavier hydrocarbon gases condense and become liquid, often causing a drop in gas pressure. Gas companies install special equipment in their systems to remove as much liquid as possible.