I would like to put a raised bed vegetable garden on top of my septic fields. It will need a fence as it is on a deer and woodchuck highway. Can I build a fence over my septic fields without ruining them:confused:

More than likely you will not cause any problems. Do you have good loamy or sandy soil with an absence of rock layers? Soil that perks properly, e.g is sandy and allows the water to penetrate to deeper levels easily will be very unlikely to be adversely affected. Field lines are generally 30" to 36" deep and while they technically do loose some moisture to evaporation it isn't much. A light garden mix of soil shouldn't cause any problem. You will likely have 500 linear feet or more of field lines and it would be a large garden that covered them all. Try not to dig into them setting the fence posts.