Current through Register Vol. XLI, No. 24, June 14, 2024
Section 38-2-23 - Performance Standards Applicable Only to Remining Operations23.1. Backfilling, Remining, and Grading of Previously Mined Areas. 23.1.a. Remining operations on previously mined areas that contain a pre-existing highwall shall comply with the applicable performance standards of the Act and this rule unless otherwise exempted in accordance with the provisions of this subsection.23.1.b. The requirement of highwall elimination shall not apply to remining operations where the operator can demonstrate in writing that the volume of all reasonably available spoil located in the vicinity of the remining operation is insufficient to completely backfill the reaffected or enlarged highwall. The highwall shall be reduced to the maximum extent technically practical. All spoil generated by the remining operation and any other reasonably available spoil in the vicinity of the operation shall be included in the permit area. For purposes of this paragraph, the term reasonably available spoil means spoil and suitable coal mine waste material generated by the remining operation or other spoil or suitable coal mine waste material located in the permit area that is accessible and available for use and that when rehandled will not cause a hazard to public safety or significant damage to the environment.23.1.c. Achieve a postmining slope that does not exceed either the angle of repose or such lesser slope as is necessary to achieve a minimum long-term static safety factor of 1.3 and to prevent slides.23.1.d. Minimize erosion and water pollution both on and off the site.23.1.e. Support the approved postmining land use.23.1.f. Spoil and waste materials shall be compacted where advisable to ensure stability or to prevent leaching of toxic materials.23.1.g. Disposal of coal processing waste and underground development waste in the mined-out area shall be in accordance with section 22 of this, rule except that a long-term static safety factor of 1.3 shall be achieved.23.1.h. Exposed coal seams, acid- and toxic-forming materials, and combustible materials exposed, used, or produced during mining shall be adequately covered with nontoxic and noncombustible material, or treated, to control the impact on surface and ground water in accordance with subsection 14.5 of this section, to prevent sustained combustion, and to minimize adverse effects on plant growth and the approved postmining land use.23.1.i. Cut-and-fill terraces may be allowed where:23.1.i.1. Needed to conserve soil moisture, ensure stability, and control erosion on final-graded slopes, if the terraces are compatible with the approved postmining land use; or23.1.i.2. Specialized grading, foundation conditions, or roads are required for the approved postmining land use, in which case the final grading may include a terrace of adequate width to ensure the safety, stability, and erosion control necessary to implement the postmining land use plan.23.1.j. Small depressions may be constructed if they are needed to retain moisture, minimize erosion, create and enhance wildlife habitat, or assist revegetation.23.l.k. Spoil placed on the outslope during previous mining operations shall not be disturbed if such disturbance will cause instability of the remaining spoil or otherwise increase the hazard to the public health and safety or to the environment.23.1.l. Any highwall remnant left after remining must be demonstrated by the operator to be stable and not pose a hazard to the public health and safety or the environment.23.2. Revegetation. 23.2.a. All revegetation shall be carried out in a manner that encourages a prompt vegetative cover which, at a minimum, shall be adequate to control erosion and is consistent with the reclamation plan. The ground cover requirements for revegetation set forth in section 9 of this rule may be modified on a case-by-case basis, by the Secretary, except that at a minimum the vegetative ground cover shall be no less than that which existed before remining and shall be adequate to control erosion. Determination of premining ground cover success and productivity shall be made using sampling techniques described by the Secretary.23.2.b. The responsibility for successful revegetation, as required by the Act, shall be for a period of not less than two growing seasons, as defined by the Secretary, after the last year of augmented seeding, fertilizing, irrigation or other work.23.3. Water Quality. A coal remining operation may qualify for the effluent limitations set forth in Title 47 Series 30 subdivision 6.2.d..23.4. Requirements to Release Bonds. Bond release for remining operations shall be in accordance with all of the requirements set forth in subsection 12.2 of this rule. Provided that there is no evidence of a premature vegetation release.