R 324.422
R 324.422 Sealing of cellars and rat and mouse holes.
Cite as Mich. Admin. Code R 324.422
Rule 422. (1) A permittee of a well shall seal and set into the earth rat and mouse hole
casings and cellars in a manner to prevent the migration of the drilling fluid and other
foreign fluids into the groundwater.
(2) Immediately after drilling completion, a permittee of a well shall fill rat and mouse
holes on all rotary-drilled wells solidly from bottom to top with cement or other suitable
material approved by the supervisor.