The University of Arizona


Risk Management Services

Polychlorinated Biphenyls (PCBs)


Background

PCB's are a subset of the synthetic organic chemicals known as chlorinated hydrocarbons. Between 1926 and 1977, PCB-containing products were manufactured for applications demanding stable, fire-resistant, heat-transfer properties. The most extensive use of PCBs occurred in dielectric fluids. Such fluids typically have the following characteristics: heavy oil appearance, high boiling point, high chemical stability, high flash point, low electrical conductivity, and low water solubility. PCBs were also used as plasticizers and additives in lubricating and cutting fluids. PCB's are clear to yellow colored oily liquids or solids. Overheated PCB material from a ruptured capacitor may be black in color. UA applications include electrical transformers, large high- and low-voltage capacitors and fluorescent lamp fixture ballasts.


During the 1970s, federal legislation mandated the elimination of PCBs from distribution in commerce. To minimize the potential for adverse health effects caused by PCBs and other substances, Congress passed the Toxic Substances Control Act (TSCA), which strictly regulates all aspects of PCB use.


EPA regulations affecting the management, removal and disposal of PCB materials began to impact the UA in the early 1980's.


Small, inexpensive, qualitative test kits can be used to determine the presence of chlorine in suspect liquids. If shown to be positive, quantitative information is available through fluid sampling and subsequent, commercial analytical testing.


PCB Transformers

These units may range in size from old, pole mount units, kettle-type pots to very large 5000 KVA units that contain over 1100 gallons of dielectric fluid. Most transformers can be found in basement equipment rooms or electrical vaults and tunnels. The UA historically has employed two management strategies for large transformers. The first is replacement. Typically, during electrical upgrade projects older PCB transformers are removed and replaced with the dry, pad mount variety. The second strategy is called retro-filling. The PCB containing fluid is replaced a number of times with a non-PCB fluid. In theory, over a period of time measured in years, all PCB's should "leach out" of the transformer carcass. After a given number of retro-fill cycles the transformer was filled with a Non-PCB replacement dielectric fluid. This method had very mixed results. Transformers with a PCB content less than 50 ppm are considered to be "Non-PCB." The only management strategy now used is the environmentally sound disposal of PCB oils through incineration and carcass smelting. All PCB transformers and capacitors must be disposed of within one calendar year after removal from electrical service.


PCB Capacitors

As part of building electrical systems, large PCB capacitors have been removed and shipped to disposal facilities. Proper disposal typically includes high temperature incineration.


PCB Light Ballasts

The majority of fluorescent light ballasts manufactured prior to 1979 contain about a teaspoon of concentrated PCB's sealed inside the capacitor. The capacitor is usually surrounded by a tar-like potting material and is enclosed in the steel ballast box. When a ballast fails, the internal capacitor may rupture and leak PCB's. The U.S. Environmental Protection Agency banned the further manufacture of equipment containing PCB's in 1979. LIGHT BALLASTS MANUFACTURED AFTER 1979 DO NOT CONTAIN PCB's AND ARE LABELED "Non-PCB's."


PCB light ballasts are shipped off-site for proper recycling/disposal. What cannot be recycled is disposed of through high temperature incineration. UA PCB wastes ARE NOT landfilled.


For questions or assistance with PCB's contact the Environmental Safety Officer, Lloyd Wundrock at 621-1590 or lloydw@email.arizona.edu.