I have a retirement cabin in Tennessee, which will be occupied full time as soon as all the pension/ssa paperwork is complete. I'm trying to precisely locate the septic tank and field - I know generally where they are. I want to put a garden in, and some fencing for a dog run, but don't want to interfere with the operation of this very important system. Does anyone have any feelings about growing a garden in/over the septic field? I don't think the tank has been pumped in the last 10 years. Any feelings on how often this should be done and how to locate the tank access lid?