This part sets environmental protection performance standards for surface coal mining and reclamation operations involving auger mining.

(a) Auger mining operations shall be conducted in accordance with the requirements of part 816 of this chapter, except as provided in this part.

(b) The regulatory authority may prohibit auger mining, if necessary to—

(1) Maximize the utilization, recoverability, or conservation of the solid-fuel resource, or

(2) Protect against adverse water-quality impacts.

(a) Auger mining shall be conducted so as to maximize the utilization and conservation of the coal in accordance with § 816.59 of this chapter.

(b) Auger mining shall be planned and conducted to maximize recoverability of mineral reserves remaining after the operation and reclamation are complete.

(c) Each person who conducts auger mining operations shall leave areas of undisturbed coal, as approved by the regulatory authority, to provide access for future underground mining activities to coal reserves remaining after augering is completed, unless it is established that the coal reserves have been depleted or are so limited in thickness or extent that it will not be practicable to recover the remaining coal. This determination shall be made by the regulatory authority upon presentation of appropriate technical evidence by the operator.

(a) Auger mining shall be planned and conducted to minimize disturbances of the prevailing hydrologic balance in accordance with the requirements of §§ 816.41 and 816.42 of this chapter.

(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

(ii) Comply with the requirements of §§ 816.41 and 816.42 of this chapter.

Auger mining shall be conducted in accordance with the requirements of § 817.121 (a) and (c) of this chapter.

(a) General. Auger mining shall be conducted in accordance with the backfilling and grading requirements of §§ 816.102 and 816.104 through 816.106 of this chapter.

(b) Remining. Where auger mining operations affect previously mined areas that were not reclaimed to the standards of this chapter and the volume of all reasonably available spoil is demonstrated in writing to the regulatory authority to be insufficient to completely backfill the highwall, the highwall shall be eliminated to the maximum extent technically practical in accordance with the following criteria:

(1) The person who conducts the auger mining operation shall demonstrate to the regulatory authority that the backfill, designed by a qualified registered professional engineer, has a minimum static safety factor for the stability of the backfill of at least 1.3.

(2) All spoil generated by the auger mining operation and any associated surface coal mining and reclamation operation, and any other reasonably available spoil shall be used to backfill the area. Reasonably available spoil shall include spoil generated by the mining operation and other spoil located in the permit area that is accessible and available for use and that when rehandled will not cause a hazard to the public safety or significant damage to the environment. For this purpose, the permit area shall include spoil in the immediate vicinity of the auger mining operation.

(3) The coal seam mined shall be covered with a minimum of 4 feet of nonacid-, nontoxic-forming material and the backfill graded to a slope which is compatible with the approved postmining land use and which provides adequate drainage and long-term stability.

(4) Any remnant of the highwall shall be stable and not pose a hazard to the public health and safety or to the environment.

(5) Spoil placed on the outslope during previous mining operations shall not be disturbed if such disturbances will cause instability of the remaining spoil or otherwise increase the hazard to the public health and safety or to the environment.

Auger holes shall not extend closer than 500 feet (measured horizontally) to any abandoned or active underground mine workings, except as approved in accordance with § 816.79 of this chapter.