Radon Mitigation - Omaha, NE

Met with Allyson and her two young kids. It's a very old home with radon levels of 8.5 in the basement, and 7 on the main level, and upstairs. It has two chambers in basement with brick wall torn out so open access to second chamber. Basement had been finished and they had water damage and demoed it. There is no sump pit or visible plumbing stack. This is not their forever home so they were looking into selling. Lo and behold, a radon mitigation appraises the value!