Polychlorinated biphenyls, or PCBs, are a class of chemicals regulated under various government programs. PCBs are very flame-resistant and thus are good for products used in electrical transmission infrastructure including plastic components.
Background
PCBs do not degrade easily, can disperse over large geographic areas, and move up the food chain rapidly. This class of chemicals is thought to be a cancer causing agent and impair immunity, harm the nervous system and impose a threat to reproductive health. PCBs have not been manufactured in products in the United States since 1977. However, products imported from other countries still contain PCBs.
PCBs are problematic because of their long-lasting and high-dispersal characteristics. PCB contamination from the 194's still presents risks to human health and the environment. EPA has prescribed cleanup methods to limit PCB risks. Once a spill occurs cleanup methods are determined by the size and location of the spill. A small spill on a nonporous surfaces may just require washing with a specail solvent and subsequent disposal of rags in a proper waste facility.
Generally, any spill or release that results in PCBs at concentrations of 50 parts per million or greater must be reported, disposed of properly and cleanup sampling must occur. If the spill has reached surface water, sewers, drinking water supplies, grazing lands or vegetable gardens, the appropriate EPA regional office must be notified to provide specific cleanup guidance.
Clean-up Methods
Spill location and size detemines what type of cleanup method to employ: Liquids with concentrations of 50 ppm or greater, no matter what type of liquid, require incineration at an approved facility. High efficiency boilers can be used for mineral oil dielectric fluid with PCB concentrations less than 500 ppm. Electrical transformers can be incinerated or disposed of in a chemical waste landfill.
Larger areas with PCB-contaminated material must be treated, capped in place or disposed of in a chemical waste landfill. One type of treatment method of bulk PCB waste is a soil washing process that removes PCBs from the soil without damaging other soil properties.
Record Keeping
There can be significant liabilities associated with PCB contamination levied through CERCLA (generally for human health impacts) and also the Natural Resource Damage Assessment (NRDA) program (generally for ecological impacts). Proper cleanup of PCBs is mandatory and good reporting and record keeping will limit your liabilities.
