Section 144-232-8-804.0 - PIPE TRENCHES804.1General: Trenches for well lines shall conform to the current edition of Chapter 238 State of Maine Internal Plumbing Rules and Chapter 241 State of Maine Subsurface Wastewater Disposal Rules.804.2Water and sewer pipes in same trench: Building sewer or drainage piping shall not be run or laid in the same trench with water service pipes or any underground water pipes unless both of the following requirements are met: 804.2.1Separation distance: The bottom of the water piping at all points shall be at least twelve (12) inches above the top of the sewer piping.804.2.2Separate shelf: The water piping shall rest on a solid shelf at one side of the common trench.804.3Fill material: Pipes in trenches are recommended not to be installed in direct contact with rocks. Use loose soil whenever possible.10-144 C.M.R. ch. 232, § 8-804.0