Section R. 325.1642 - Belowground well casing connectionsRule 142.
(1) A connection to a well casing that is made below the ground, or less than 12 inches above the ground surface, shall be protected by approved threaded or welded joints or by an approved pitless adapter. A belowground connection shall not be submerged in water during installation.(2) Clamp-on, saddle-style pitless adapters shall have both gaskets pressurized by water from the pump so that any water leakage will be from the pressure system outward. A pitless adapter shall provide complete clearance within the internal diameter of the casing and shall vent the casing if required by the provisions of R 325.1657. A person shall not install a pitless adapter that has not been approved, in writing, by the department.Mich. Admin. Code R. 325.1642