Carpet Weedkiller?

As we work on our garden, we read or hear about ideas that have worked well for others and are eager to try these things. I am not sure that all of these are GOOD ideas, but since this is the 'show me' state, we like to see these things for ourselves.

Steve (friend with much more gardening experience) told me about a house he recently worked on, a very nice house that belonged to an old woman who'd passed away. The garden space was covered by old carpet, and at first Steve could not understand why anyone would do such a thing. Ugly outdoor patio area? Garden as landfill? He removed the carpet and saw the rich, weed-free soil underneath, and realized this must have been this old-timer's way of prepping for the following season.

I was especially excited about the idea of using old carpet. We'd pulled up some nasty carpet from our house when we first moved in. It was part of our 'greening' up the house efforts, but I knew that carpets were a major issue in landfills and wasn't looking forward to being part of the problem. With this new idea, I could put the carpet to work AND keep it out of the landfill. Happy days.

But now, I am concerned. Since carpets leach toxins (one of the reasons they are a problem in landfills) it’s possible that our carpet is doing just that, right now, in our vegetable garden! How will I know if my soil is safe? I am hoping it will be okay, especially after we add the layers, but I would hate to think our effort to do something green turned out to be really, really brown.

I asked for help in the ever-entertaining “I Dig My Garden” forum on the Baker Creek website, and got a wide range of suggestions and helpful (and not as helpful, but funny. High heels? Oh, it does digress there) advice. Ultimately, though, I don't think anyone knows for certain. I will probably remove it, just to be safe. After all, we will be topping all of this off with cardboard, newspapers, leaves, compost and soil in the Spring.