Well, for all of you living in Wisconsin, mainly in the southern part by Madison/Milwaukee, and on the western shores of lake Winnebago, you are sitting on a large chunk of Uranium 234 (i think thats the one we were sitting on, could be U84 or something like it). this stuff decays and turns into radon gas and eventually seeps up into your basement, known for causing lung cancer. the federal law on this is that you can have at max 4 pcI/L of it in your basement. if you have more than the legal limit, you must spend 800-1000 dollars just to get something to clean it out, or you could open a window and have it flushed out like that, but thats a big problem in the winter.
just thought i should share.