Disposal & RecyclingThe lifespan of treated poles depends on factors such as the type of wood, climate, and type of treatment. The average expected useful life is 30-50 years, but the turnover in urban areas is more rapid because of changes in pole location due to changing utility service or street repair and modification.
Disposal methodsIn excess of three million poles are removed from service each year. Largely due to intense lobbying by the wood preserving industry, there are very few restrictions on the disposal of chemically- treated wood poles. Treated wood is not considered a pesticide and therefore not subject to the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA). Reused wood is not a waste and therefore not subject to the Resource Conservation and Recovery Act (RCRA.) Treated wood that is no longer usable is waste, but has not been listed as hazardous waste. Therefore, several different disposal methods are available nationwide.
LandfillTreated wood is eligible for disposal in municipal landfills and a great deal is sent to them.
IncinerationTreated wood poles are burned for their energy value in co-generation facilities permitted for burning treated wood, in hazardous waste incinerators, and in the fireplaces and wood stoves of scavengers. Burning of penta-treated wood releases dioxins into the air. Arsenic and chromium VI are released in the burning of arsenicals.
Disposal in hazardous waste facilitiesSo far, disposal as hazardous waste is an option that has been avoided. While this represents an out-of-pocket savings for the utility industry in the short-term, it represents a real hazard to communities with associated long-term cleanup costs.The Electrical Power Research Institute estimates that "by avoiding the hazardous waste designation, the utility industry will save $15 billion between 1989 and 1993." For example, despite classifying the wood preserving chemicals as hazardous waste in levels often found in used poles, the state of California has exempted Pacific Gas & Electric (PG&E) from disposing poles in hazardous waste landfills. The long-term impacts of this decision could be vast.
Reuse and recyclingMany poles are reused by farmers or others who receive them from utility companies. At least one company recycles poles for reuse by shaving them down, recovering wood preservative from the shavings, retreating them as smaller poles, and selling the processed shavings for a filler for asphalt shingles.
Chemical recovery/bioremediationProcesses for removing and/or reclaiming wood preservatives from unusable poles are being researched, but not used commercially, except in the pole recycling operation cited above.
Risks of disposal and reuseEvery method of disposing of treated wood poles in general use poses substantial risks. The reuse of poles by people who are not familiar with the risks associated with exposure to the toxic chemicals is very likely to lead to problems. Often poles are used for landscaping, for building - dwellings, animal shelters, and even children's play equipment - and for fence posts. Children can be exposed directly or through contaminated soil. Poisons can be picked up by vegetables, by farm animals or by pets.
Wood preservatives are known to migrate away from poles in service in concentrations that are high enough to be toxic to aquatic organisms. In landfills, many poles may be disposed of together, so the concentration may be even higher.
Burning is particularly hazardous, since extremely toxic compounds may be carried great distances, to be breathed directly or concentrated in other organisms after falling to the ground.