I hope that someone can help me. I am installing a septic system for the first time. I have a 1000 gallon concrete tank already in the ground and the pipe running from the house to inside the tank but need some help. I have the washed rock under the piped coming out of the house, Can I just cover it up with the dirt now? Also I need to know how wide and deep the leach lines need to be? How much rock needs to go under the pipe first in the lines with the pipe sitting on top of them? Will plastic be fine on top of the holed pipe and then the dirt? Hope that someone understands my questions and can help. Also what machine is best to dig the leach lines? Thanks