No doubt, you’ve heard the rumblings of using pressure treated wood, not only for raised garden beds but for play sets, decking, picnic tables, and more. The concerns are valid leading to its withdrawal from the marketplace in 2004 and safer alternatives. From changes in the chemicals used to treat wood to more rot resistant, natural choices and even post-consumer recycled products, eco-friendly gardeners have plenty of choices these days. Yet chances are pretty good that you have at least some of this wood somewhere in your yard or garden right now.
All the hype came about when lumber was impregnated with chromated copper arsenate. You know it as “CCA”. It was to be the answer for anyone needing an inexpensive choice for long-lasting, rot-resistant lumber. It was readily available and touted as safe, even though the wood was treated with chemicals that were all toxic (chromium, copper and arsenic).
Pressure treated (CCA) lumber has enough toxic chemicals to qualify as a hazardous waste. It’s hard to believe but just one 12 foot long 2×6 piece of CCA lumber contains enough arsenic (one ounce) to kill over 200 people. But what’s even more unbelievable is that industry lobbyist in Washington, D.C secured an exemption of CCA treated wood from hazardous waste disposal laws.
Armed with that interesting tidbit of information, it is not surprising then to find that the EPA doesn’t offer much assistance when it comes to specific help regarding the safe disposal of CCA lumber. In fact, disposal information is only one sentence: “CCA treated wood can be disposed of with regular municipal trash (i.e., municipal solid waste, not yard waste).” That may be alright with you but that’s no comfort to me when you learn that the U.S. Department of Energy projects over 400 million board feet of it will be disposed of by 2016. And I’m allowed to just haul my old CCA wood to the dump and walk away. Wow!
Although it is illegal to incinerate CCA treated wood in all 50 states, it is often burned by individuals as scrap firewood, in campsites and construction sites, all the while releasing highly toxic chemicals into the air. Furthermore, the resulting ashes contain potentially fatal levels of arsenic that can easily be inhaled. And then there are a few overly resourceful recyclers that choose to grind up CCA lumber as mulch and then sell it to us so we can put it back into or gardens and around our food crops. This is a very bad idea!
Even placing discarded CCA lumber into unlined landfills where it leaches into the earth and can be potentially carried into ground water is alarming, as are the rest of the examples cited above. Unfortunately, all these methods of disposal and more are implemented every day.
Landfills that have protective liners are currently the most eco-friendly way to dispose of treated wood. Liners prevent possible seeping of contaminants into ground water and provide a much safer disposal method than disposal into unlined landfills.
New ways of safely disposing of CCA treated lumber are being explored around the world. Incineration methods are in various stages of development that may someday provide another option for disposing of CCA wood in a safe and viable manner.
It seems surprising that in spite of the abundance or CCA treated wood in existence, there are not more options for disposing of it safely. You may have better luck by checking with your local government or municipal authorities. They may offer additional disposal resources or provide information and restrictions on disposing of CCA treated wood in your community.
I recognize that I haven’t offered you much in the way of specific suggestions for the safest and most environmentally friendly disposal methods of CCA treated wood. And that’s simply because today, there aren’t many. But I hope that by at least reading this article, you are more aware of the potential problems of disposing of it improperly, and at least that’s a start.