Good site!!! My house is 40 years old. The previous owner replaced the septic tank in the mid'80's and the system has worked fine since. I am getting ready to sell my house and it was suggested that I get an septic certification. I called a well respected company and they couldn't find the a holding tank. My plumber used a sowser and found what he believes is a drain field. There is no lid to inspect the field. What should I do? Thanks, Chuck