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Railroad Ties are NOT Legal for Home Landscape Use
Q: Pattie writes: "I recently bought a house just over the Pennsylvania border in Maryland. The previous owner had many garden beds, and the one he used for vegetables had old timbers surrounding it that looked questionable. I asked him if they were 'treated wood' and he said he didn't know; that they were there when he purchased the house over ten years ago. The timbers are rotted and in bad shape. How do I find out whether they are treated wood; and if they are, do I need to remove all the soil? Is there a place I could take a piece of wood to show someone or have it analyzed?"
A. Pattie attached photos that show badly rotted timbers; some with a telltale green color—which might be mold, but more likely it's a sign that the wood was treated with arsenic or other toxic wood preservative. So I went to the EPA to see what kind of advice they had for people who discover that they have the worst kind of wood on their property: Old railroad ties. And what I discovered was shocking.
(And I don't shock very easily…)
Every EPA site said the same thing about the main preservative in old railroad ties: "Creosote is a possible human carcinogen and has no registered residential use." So it's actually illegal to use old railroad ties in a home landscape.
Again, I quote the EPA: "Creosote is not approved to treat wood for residential use, including landscaping timbers and garden borders. There are no approved residential uses of creosote treated wood. The Agency is aware that creosote-treated railroad ties are being used in the residential setting for landscape purposes and as a border around gardens. Such uses in residential settings are not intended uses of creosote. If you have creosote-treated wood in your yard, consult the handling precautions outlined in this document."
Now—you may be scratching your head and saying, "but I think I've seen old railroad ties for sale recently." And you probably have. I found one online seller who specializes in them, boasting on their website that "Used railroad ties are great for retaining walls and other applications around the house."
…Which, since it's an unapproved use of a registered pesticide, can't be legal. But it doesn't look like there's any enforcement. I found old railroad ties for sale this month at the website of one of the 'big box' national home center chains (not modern 'imitations' either—"old railroad ties").
If you see old railroad ties for sale, report the seller to the EPA; and warn your friends not to buy them.
And people like poor Pattie, who 'inherit' them?
They can have the wood and soil tested for arsenic, creosote, chromium and other worrisome wood preservatives, but the tests can be expensive, and the odds are so strong that old wood was toxic that I would just cut to the chase and spend the money on safe removal, following the EPA guidelines for old railroad ties: Don't touch the wood with bare skin; don't let animals or children near it; don't let it get near a water supply; don't inhale the dust; wear protective equipment when you handle it—including gloves that are "chemically impervious"; and don't burn it—the fumes can be deadly.
Now: Back when I was younger, I might have felt comfortable doing this kind of removal work myself. But I am no longer younger; and I have become, as my Pennsylvania Dutch neighbors like to say, "Too soon old; too late smart", which means I now realize that I might have been tempted to cut corners back in my youth thanks to the invincibility felt by all men previous to their third or fourth decade on this planet. (IF they get that far.)
Older, and thankfully, wiser (there was honestly only one direction to go in) I now realize that the cost of buying the right kind of protective gear would probably be close to the same as paying professionals to do it. So today, I would get bids from several local companies that do asbestos removal—they already have the expertise, the right protective equipment, and perhaps of equal importance: access to safe disposal options—and get pros to do it.
Have them remove all the rotting wood and the top inch of soil. Then the homeowner or a landscaper —wearing long sleeves, protective gloves and a heavy duty dust mask—can have soil brought in to level the area, lay cardboard over the soil, frame out raised beds, drop them on top of the cardboard and fill them with topsoil, compost and perlite (as discussed at length in our previous Questions of the week on raised beds—found under the letter R). You can use non-dyed wood chips or bark mulch to cover the two-foot-wide walking lanes between the beds, but nothing weirdly colored or bad smelling.
Then you'll be growing in clean soil for sure. And there won't be contaminated soil or sawdust blowing around for people to inhale or otherwise come into contact with. As we've stressed in the past, the big danger with treated wood comes from inhaling the toxins and absorbing them through your skin—so "just growing ornamentals there" as opposed to food crops isn't a safe option. Do it right; you'll sleep better at night, and you'll also get highly productive garden beds out of the deal.
You can even take your time and build a few of the new raised beds every season—my 'go slow' approach for people who have just moved into a new place. But that's just for building the new beds. I'd want all the old wood and that top inch of soil out of there right away. Otherwise, the people in that house are in danger of inhaling toxins every day.
And if those people were to try and work in un-remediated soil without protection, they'd risk ingesting the chemicals through inhalation and skin contact; and even worse, getting a toxic splinter. No matter what kind of wood treatment was used, the splinters are nasty!
So get rid of it. The only legal use for railroad ties is ON a railroad.
EPA on railroad ties: