PCBs -- still a potent problem

By John Crowe, Gary Steacy Dismantling Ltd.

This skillet contained PCB contaminated oil at 587,000 ppm.

The mere mention of polychlorinated biphenyls can still cause many people to shudder. These once life-saving chemicals have been blamed for everything from cancer to low intelligence. The push has been on since the 1980s to rid ourselves of this material and everything with which it has come into contact.

Since its inception in 1987, the Swan Hills treatment centre in Alberta has processed close to 200,000 tonnes of waste, much of this PCB waste. Our company's privately owned and operated PCB waste incinerator in Colborne, Ontario, started operation in 1998 and has processed over 3,500 tonnes of PCB waste since receiving its Certificate of Approval. Add to these incinerators the companies that are decontaminating waste equipment with solvents and sodium-based solutions and you have large amounts of PCBs that have been processed.

Yet there is still a large volume of PCB contaminated equipment both in use and in storage. Apparently, many generators of PCBs, with waste in storage, are still holding on to their inventories, hoping that prices will fall or perhaps that the regulations will change. However, due to the price of petroleum-based products, prices are starting to creep upward and the regulations are changing. They are becoming more strict. Equipment that had been considered PCB-free may soon be considered PCB-contaminated.

So why all the fuss about getting rid of PCBs? After all, because of their very high flash point and great stability, they were used in everything from electrical equipment to newsprint to floor tiles. Even cooking utensils such as electric skillets may contain high levels of PCBs. The chemical itself is not yet proven to be a highly toxic health hazard. It is a persistent chemical, however, in that it does not readily break down in the environment and it also bioaccumulates.

But the real hazard in PCBs is when they are degraded through heat at a relatively low temperature, less than 1,000 degrees Celsius. At low temperatures, such as in a house fire or transformer fire, the PCBs release polychlorinated dibenzodioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and quaterphenyls (PCQs) into the atmosphere. These are proven health hazards. Even the burning out of a simple fluorescent light ballast can release a small cloud of acrid smoke contaminated with dioxins and furans. It was the dioxins and furans in the PCB-contaminated rice oil incidents in Japan and Taiwan in 1968 and 1978 that started the PCB hysteria of the '70s and '80s. The PCBs were thermally degraded during the cooking which formed the toxins.

Generally, an article containing a concentration of 50 parts per million (ppm) or more of PCB was considered PCB material, except for Saskatchewan where the limit is 5 ppm. Until the CCME guidelines for Transformer Decontamination were recently adopted, Ontario, under the Gott's Rule, allowed PCB-contaminated transformers of up to 500 ppm to be sent to landfills and other non-regulated sites as long as they were carefully drained and redrained. It has been our experience that even with the most carefully drained transformers, one or more barrels of residual PCB oil that had leached out of the porous materials could still be drained from a truckload of transformers.

Perhaps some of this oil that could be drained off, made its way into the soil and some was possibly saved by an economy-minded landfill or yard operator to be burned in an oil-fired heater. The limit now in Ontario is 200 ppm.

Presently, incineration is the only way to totally destroy all traces of PCBs while leaving no contaminated residues or other contaminated substances; however, great strides have been made in bioremediation. Someday, even incineration may be replaced.

Whether or not a limit of 2 ppm comes into effect nationally under the proposed amendments to the Chlorobiphenyls Regulations and to the Storage of PCB Material Regulations under the Canadian Environmental Protection Act, there is still a large inventory of PCB contaminated waste held in storage. The Ministry of the Environment in Ontario has begun a push to convince holders of these inventories to dispose of them sooner rather than later. The longer this waste is kept in storage, the greater the risk of containers deteriorating and the greater the risk of an incident.

Until the waste is received at a regulated waste disposal site, holding a Certificate of Approval for that waste, ownership and, therefore, the consequences of any incident, remain with the generator.

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