On Wednesday, June 29, 2016 at 9:54:08 PM UTC-4, wrote:
The foundation drain sump pit is where you can expect to find radon, if anywhere. The sealed unit you are talking about shouldn't have any place for radon to infiltrate.



Aren't the foundation sump pits perforated to allow water to enter?

If water can get in, so can radon.

I think a small air pump pulling air from the pit to the outside is good for getting rid of odor as well.