Doesn't sound good, does it? Even if I didn't know it is caused by the break-down of Uranium, and omits gas that isn't like Aunt Edna's, smells bad but won't hurt you much. Radon doesn't smell bad and can cause cancer and bad stuff. As a matter of fact it does not smell at all and you have to test for it.
When I cut a 5" wide trench and a approx 30" hole for an extra sump pump, I got a test kit and tested for it. Get them at hardware stores, un-cap two cannisters for 4 days, send them in with $30.00 and you get a result back in a week or two. Concrete can be porous and emit Radon gas right through the concrete, you don't even have to cut it. I ran another test about 8 years ago here.
My average level was 3.1 pCi/L the average level across the U.S. is 1.3 pCi/L The EPA's 'Action level' is 4 pCi/L
So, I guess we are Ok.
If you haven't checked your basement in your stick home, it would be a good idea.
This explains it better than my mumblings abut it:
http://www.radonseal.com/radon-indoor.htm
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