We just completed a very complicated mitigation system design & installation in southeast Canton, Ohio. This 2200 sf colonial was built in 1985, and has a nice sized addition with crawlspace in the rear. The basement was finished, and the finishers decided to build walls OVER the sump pumps! So, we had a crawlspace to contend with and goofy construction practices. Luckily, we were able to reduce the radon levels from 5.3 pCi/L to 1.3 pCi/L. Here’s some pics and videos: