WHITE PAPERS

DOES TREATED WOOD USED FOR POSTS, POLES, AND IN OTHER GROUND CONTACT APPLICATIONS LEACH CHEMICALS INTO THE SOIL?

Excerpted from Frequently Asked Questions About Preserved Wood, A Guide for Consumers and Wood Industry Professionals, Third Edition, American Wood Preservers Institute:

Several studies have been completed by utility companies and by universities addressing the migration of preservatives from poles. These studies indicate that preservatives from poles do not cause ground-water contamination. Penta and creosote are biodegradable, and minute quantities of preservatives that enter the soil around the pole are absorbed into the soil due to the affinity to organic material. The concentrations of preservatives released from treated wood pose no threat to human health and the environment.

Late in 1993, the Tasmanian (Australia) Parks and Wildlife Service published its study on the effects of CCA-treated wood walkways, some of which had been in place for 15 years. The study, which included soil sampling and laboratory research, concluded that the treated-lumber poses “very low risk to the environment and workers”, and pointed out the advantages of treated wood.

The preservative in CCA pressure-treated wood constitutes only several percent of the product, by weight. More importantly, the preservative is driven deep into the wood cells, where it undergoes a chemical reaction to convert it into an insoluble mineral form that is highly leach-resistant.

Data collected to date demonstrate that any leaching from copper naphthenate-treated wood into the soil will remain very close to the source and not move readily into surrounding soil or ground water.

 

“PRESSURE TREATED WOODEN UTILITY POLES AND OUR ENVIRONMENT”, BY DR. KENNETH BROOKS

Excerpted from North American Wood Pole Coalition Technical Bulletin:

Conclusions: There are environmental risks associated with everything we do and with all of the materials used to construct utility structures. For instance, Morris (1998) documented the leaching of zinc from steel utility poles and found concentrations around two of five poles that exceeded the Canadian Council of Ministers of the Environment (CCME, 1997) benchmark of 200 mg zinc/kg soil for residential and agricultural use.

It is a basic truth that essentially every human activity – from the soil erosion associated with growing the wheat for a loaf of bread to producing the power that runs our appliances – has an associated environmental cost and risk associated with it. As environmental management matures in North America, we will better understand that, lacking an ability to eliminate risk, well educated societies everywhere will turn from the polemics of risk aversion to the more proactive and fruitful task of risk management.

Automobile travel is certainly Risky Business. We manage those risks with stop signs, speed limits, air bags, and a host of rules that, if followed, can make any journey much safer – but not risk free. Appropriate rules are also required to manage the environmental risks associated with our utility infrastructure. Years of research and experience have developed a strong basis of science supporting a conclusion that properly produced and used utility poles pose minimal and totally manageable environmental risks.

The Utility industry can assure worker safety and environmentally appropriate use by carefully adhering to the guidelines in the Consumer Information Sheet and the MSDS for the treated wood product provided by the producers.
Utility poles removed from service can appropriately be reused for landscaping and other non-structural applications by the public. Utilities should ensure proper transfer of ownership and should supply a Consumer Information Sheet to the new owner.
Computer risk assessment guides are available for evaluating uses in especially sensitive aquatic environments where the treated wood utility poles need to be carefully managed.
Following these simple guidelines can insure that the long history of safe pressure treated wood use continues into the future. Properly produced and used, pressure treated wood utility poles pose no greater risk to the environment than growing the wheat used to bake your next loaf of bread, and present far less personal risk than driving to your local grocery store to purchase that bread.

 

HOW LONG WILL PRESERVATIVE-TREATED WOOD LAST?

Excerpted from Frequently Asked Questions About Preserved Wood, A Guide for Consumers and Wood Industry Professionals, Third Edition, American Wood Preservers Institute:

OIL-BORNE PRESERVATIVES: Pentachlorophenol was first described in scientific literature in 1841, and has been commercially produced since 1936. Due to penta’s wide-ranging properties and relatively low cost, it has been widely used for generations to preserve wood. It is primarily used for the treatment of utility poles, and it is not unusual to find penta poles installed in the early 1930s still in service today.

WATER-BORNE PRESERVATIVES: The use of water-borne preservatives results in wood that retains its structural integrity from ten to twenty times longer than untreated wood. Wood treated with water-borne preservatives and installed as far back as the 1930s is still in use and in serviceable condition today. The Bell Telephone System began using CCA-treated utility poles in 1940. As with creosote- and penta-treated poles, when CCA-treated utility poles are removed from service, the reason is more often related to the need for larger poles, auto accidents, etc., than to failures caused by fungal decay or termite attack.

 

DOES PENTA MIGRATE FROM TREATED WOOD?

Excerpted from Frequently Asked Questions About Preserved Wood, A Guide for Consumers and Wood Industry Professionals, Third Edition, American Wood Preservers Institute:

Tests have shown that penta migration from utility poles adsorbs into the adjacent soil and migrates only a very short distance from the pole.

When properly applied, penta remains in treated wood products for many years. Penta is broken down by sunlight, however, and it is also degraded by certain bacteria when penta is present in low concentrations. Consequently, over time, wood surfaces become relatively free of penta while the preservative continues to work against microorganisms below the treated surface.

 

CAN WOOD TREATED WITH PRESERVATIVES BE BURNED?

Excerpted from Frequently Asked Questions About Preserved Wood, A Guide for Consumers and Wood Industry Professionals, Third Edition, American Wood Preservers Institute:

As with many building products, treated wood should not be burned in open fires or stoves, fireplaces, or residential boilers.

Wood treated with water-borne preservatives must not be burned because combustion breaks the unique bond formed between the preservative and the wood. When this bond is destroyed, the components of the preservative can be released in the form of ash and particulates. These can be harmful if inhaled. The American Medical Association also advises against burning plywood, particle-board and old furniture.

Treated wood should only be burned in an approved commercial or industrial permitted co-generation or incinerator facility which is properly permitted to accept the treated wood under the applicable state and Federal regulations.

 

WHAT IMPACT DOES PRESERVATIVE TREATMENT OF A UTILITY POLE HAVE ON STRENGTH?

Excerpted from Frequently Asked Questions About Preserved Wood, A Guide for Consumers and Wood Industry Professionals, Third Edition, American Wood Preservers Institute:

Generally, the type of preservative used to treat the wood will not affect its strength. Before a pole can be treated with any type of preservative, moisture must be removed from the wood to make room for the preservative. The removal of the moisture from a utility pole can be accomplished by steam conditioning, air drying or kiln drying.

Drying processes may affect the mechanical properties of wood. Utility companies design their products with the consideration of drying properties, wood species, and preservatives that are to be used.

 

WHAT PRECAUTIONS SHOULD LINEMEN TAKE WHEN CLIMBING PENTA- OR CREOSOTE-TREATED UTILITY POLES?

Excerpted from Frequently Asked Questions About Preserved Wood, A Guide for Consumers and Wood Industry Professionals, Third Edition, American Wood Preservers Institute:

Linemen who climb utility poles are advised to wear long-sleeved shirts, pants, and gloves to avoid splinters. The same gloves that linemen use to handle electrical components are adequate for climbing poles.

 

“WOOD POLES REMAIN BEST LONG-TERM INVESTMENT, ACCORDING TO EDMI STUDY”, BY DENNIS HAYWARD

Excerpted from Electric Light and Power, October 1997:

Conclusion: The maintenance and inspection costs, which are incurred several years following initial line construction, are not the major determinants of present value. As a general rule, wood pole lines tend to be the most costly to maintain. Even so, this example shows that the costs of future inspection, maintenance and pole replacement add only 5 to 11 percent to the present value of a wood pole installation and 0 to 1 percent to the present value of an alternative material pole line.

Although this results in a decrease in the cost advantage of wood when compared to alternative material, it does so to a lesser degree than is often perceived. The actual calculated difference in post-installation costs between wood and the alternative materials ranged between just 5 and 10 percent of the initial installation cost. This equates to $30 to $90 per pole for most distribution lines and $100 to $300 per pole for most transmission lines.

Because the post-installation cost differences in many cases are not great, the major factor in the economic evaluation for pole selection is the initial cost for materials and labor. Wood poles tend to have the lowest construction costs for most pole sizes.

For most overhead line applications, treated wood – compared to steel, fiberglass or concrete – remains the most cost-effective material in terms of initial costs as well as total life cycle costs.

 

HOW SHOULD I DISPOSE OF PRESSURE-TREATED WOOD?

Excerpted from Frequently Asked Questions About Preserved Wood, A Guide for Consumers and Wood Industry Professionals, Third Edition, American Wood Preservers Institute:

Before considering disposal, an option to reuse or recycle the used treated wood product should be considered. Treated wood can be reused in a manner compatible with its original purpose, such as fence posts, retaining walls, landscaping, decks, general construction and the like. For example, railroad ties or utility poles may often be reused in erosion containment projects. Many utilities sell or give out-of-service preserved wood poles to businesses, farmers, and others – recycling the material and helping ease demand on forest resources. When poles are transferred to others they are accompanied by information on the proper use of the products and information on good handling practices.

Pressure-treated wood is not a hazardous product and, although it contains a pesticide in the cells of the wood, it is not a hazardous waste.

You may deposit treated wood in a landfill. However, due to the growing shortage of landfill space, many industrial users are recycling treated wood as a disposal option.

In cases where the wood cannot be reused, creosote- and pentachlorophenol-treated wood are increasingly being utilized as fuel in properly permitted industrial burners for the generation of steam energy to power a manufacturing plant on-site and to co-generate electricity which may be fed into the electric utility power system.

 

  • BROWN WOOD PRESERVING CO., INC. 

    Headquarters

    6201 Camp Ground Road
    Louisville, KY 40216
    Telephone: (800)537-1765 / (502)448-2337
    Fax: (502)448-9944

    BROWN WOOD PRESERVING CO., INC. 

    Kennedy Plant

    16851 AL-96
    Kennedy, AL  35574
    Telephone: (205) 596-3529