pressure treated wood next to my garden!

Help! My neighbors are building a retaining wall on our property line right next to my vegetable garden, the only really sunny place in my yard.
they are burying pressure treated wood there. I called the city and they say it is legal. supposedly later today the "boss" is returning and they kind of said "if you ahve a problem we can use something else." but the owner of the house next door already told me that stones "were too expensive" --I can't believe it would be THAT much more expensive it is basically just filling in a little trench along the property line (they say to stop the ground from being carried away in the rain as their property is on a hill. mine is more flat so their rain would run into my yard).
this stuff is coated with arsenic?
How about Trek? would that be better?
Thanks for any help you can offer! theresa

Well, first you have to do a little research. Most of the treated lumber these days is not the kind treated with arsenic. It's treated with other stuff. I got the next 3 paragraphs off a website about the stuff that IS arsenic treated (which is probably not what they are using) so this would be your worst case:

Most treated lumber over the past two decades has been treated with CCA (chromated copper arsenate). Recent research by Prof. Carl Rosen, Department of Soil, Water and Climate at the University of Minnesota, and his colleagues, has shown that CCA treated landscape timber about 10 years old does leach chromium, copper and arsenic into the soil. The levels of all three elements were highest near the timber, and were near normal background levels a foot or so away. Furthermore, Rosen's group also showed that vegetable plants grown in soil taken from within 1 inch of the timber will take up arsenic (though not chromium or copper).

The amount taken up was measurable but substantially less than U.S. Public Health Service standards and also substantially less than Canadian statutory limits. Some argue, however, that these standards are not sufficiently strong and not scientifically based. For further details about this study, see this Yard and Garden Newsletter: http://www.extension.umn.edu/yardandgarden/YGLNews/YGLN-June0101.html#as

The EPA and the lumber industry have agreed to stop sales of CCA treated lumber starting in 2004. One reason for this is that there are now good arsenic-free alternatives. Some of these alternatives are discussed in this Yard and Garden Newsletter: http://www.extension.umn.edu/yardandgarden/YGLNews/YGLN-July0101.html#wood Note that one alternative is to use naturally rot- and insect-resistant woods such as redwood or cedar.

Okay, secondly, Trek would be better but way more expensive and also since it's made from wood "dust" that is encapsulated in plastic, it might also break down over time. The composite manufacturers seem to like to say that it doesn't break down over time, but experience of those I know with those composite timbers seems to indicate otherwise.

Now, on the positive side, if it's the newer kind of treated lumber, then it's probably not as much of a concern. Scroll down on this site (past all the stuff on the arsenic type, which gives you more info than I gave above) and look at the paragraph on ACQ treated. That is probably what they are using. Try to find out from the "boss" when he is back. It would certainly be preferable.
http://www.taunton.com/finegardening/pages/g00028.asp

HOpe this helps!
CMox

wow that is so helpful, thanks! I'll do some reading and talk to the "boss." I'm willing to help wiht costs just I wasnt told about this till this AM and it all came as a shock. ........
m aybe I should ask to see the receipt to verify it is the newer type of wood.......
thanks again! theresa

Usually there is a stamp or a sticker on the lumber that indicates ACQ or other abbreviations so you can probably look right at the wood if it's visible. And if it doesn't say ACQ but it says something else, you can probably look it up online. Our local hardware stores (i.e. Mendards, Home Depot, Lowes) all carry that new stuff. I hope that's what they're using, and I hope they'll be up-front with you about it. It's only going to be that old stuff with the arsenic if they are trying to use up old stock purchased pre-2004.

In any case - let us know how it works out!
C.

The other thing that the studies on pressure treated wood all seem to say is that, even with the old arsenic-treated wood, the problem is with *unsealed* lumber. A couple of coats of polyurethane on the wood before it goes in should also make it safe... We did that with our deck posts, since several years ago we could get decking made the "new" way (which I think involves some sort of citrus oil), but 4x4 posts were only available with the old arsenic-treated method.

Hopefully, the wood will be the "right" kind, and you won't have to be concerned!