30 CFR 819.15 - Auger mining: Hydrologic balance.
(b) All auger holes, except as provided in paragraph (c) of this section, shall be -
(1) Sealed within 72 hours after completion with an impervious and noncombustible material, if the holes are discharging water containing acid-or toxic-forming material. If sealing is not possible within 72 hours, the discharge shall be treated commencing within 72 hours after completion to meet applicable effluent limitations and water-quality standards until the holes are sealed; and
(2) Sealed with an impervious noncombustible material, as contemporaneously as practicable with the augering operation, as approved by the regulatory authority, if the holes are not discharging water containing acid-or toxic-forming material.
(c) Auger holes need not be sealed with an impervious material so as to prevent drainage if the regulatory authority determines that -
(1) The resulting impoundment of water may create a hazard to the environment or public health or safety, and
(2) The drainage from the auger holes will -
(i) Not pose a threat of pollution to surface water, and