Jeff, what is this for? Septic? sump pump? where do you live? if you are burying a pressured line keep it below the frost line.Ct/ ny is 4ft. use a schdule 40 pvc. if it not under pressure use a 1/4 inch per foot pitch to where you are discharging too. it can be any where in the ground. Watch out for power lines, Water lines Sewer/Septic lines, and most important Gas lines, when you are getting ready to dig!! I hope this helps you!! I tried