MSHA - Code of Federal Regulations - 30 CFR 77.1915
30 CFR § 77.1915
Storage and handling of combustible materials.
(a) Compressed and liquefied gas, oil, gasoline, and other petroleum
products shall not be stored within 100 feet of any slope or shaft
(b) Other combustible material and supplies shall not be stored
within 25 feet of any slope or shaft opening.
(c) Pyritic slates, bony coal, culm or other material capable of
spontaneous combustion shall not be used for fill or as surfacing material
within 100 feet of any slope or shaft opening.
(d) Areas surrounding the opening of each slope or shaft shall be
constructed to insure the drainage of flammable liquids away from the slope
or shaft in the event of spillage.
(e) Oily rags, waste, waste paper, and other combustible waste
material disposed of in the vicinity of any slope or shaft opening shall be
stored in closed containers until removed from the area.