Speak to a local attorney about this regarding the specifics of the facts. In my state we have disclosure forms and a process by which sellers have to provide a certificate showing that septic systems are in compliance with the law. Not sure about WV if that is a strictly seller or negotiable requirement. The general rule in all states is "let the buyer beware", meaning that if the seller wasn't asked a question, he doesn't have to volunteer info. However, if asked, he has to be truthful. If the condition of the septic was asked about, or was a subject on the disclosure form and misrepresented, or was the subject of a requirement that he demonstrate compliance with state enviro law re: septic systems, then it sounds as if you might have a good case for misrepresentation. But please speak to a local attorney about the specifics.