My basement had an average radon level of just over 4.0 so I designed and installed a radon mitigation system myself. Using 4" PVC pipe venting from the sump pump pit cover in the basement, through the wall outside where it connects with the RadonAway fan and remaining PVC pipe up the side of the house venting above the roof line. Radon levels dropped from around 4 to 0.3 on my electronic detector. So I have concluded that my radon mitigation system is a success! Everything continues to run smooth and quiet.