I believe Esshup has mentioned a tamper that is good for small areas like around a pipe. I will tell how I did it, but its not the proper way. I used a backhoe to sprinkle light layers of dirt, then I took the opposite end of a spud bar and used it as a ram to manually tamp the dirt. Long process, doing each layer at a time. My pipe is not that deep, so I do not have a lot of pressure against it, about 3' of water. I do not have a leak yet, it has been in use for a year or so. If I had known about this forum before installing mine, I would have set it up as a siphon drain. Live and learn. I could have used the teeth on the bucket to act like a tamper, but just didn't want to take a chance of damaging the pipe. I don't see how a dozer could "tamp" around a pipe properly, but then again, I never run one, so perhaps I shouldn't be so judgmental.
