§ 816.102 - Backfilling and grading: General requirements.

§ 816.102 How must I backfill the mined area and grade and configure the land surface?

(a) You, the permittee or operator, must backfill all mined areas and grade all disturbed areas in compliance with the plan approved in the permit in accordance with § 780.12(d) of this chapter

Backfilling and grading: General requirements.

(a) Disturbed areas shall be backfilled and graded to -

(1) Restore Achieve the approximate original contour as the final surface configuration, except in the following situations:

(i) Mountaintop removal mining operations approved under § 785.14 of this chapter.

(ii) Sites for which the regulatory authority has approved a variance under § 785.16 of this chapter.

(iii) Operations to which the thin overburden standards of § 816.104 of this part apply.

(iv) Operations to which the thick overburden standards of § 816.105 of this part apply.

(v) Remining operations on previously mined areas, but only to the extent specified in § 816.106(b) of this part.

(vi) Excess spoil fills constructed in accordance with § 816.71 or § 816.74 of this part.

(vii) Refuse piles constructed in accordance with § 816.83 of this part.

(viii) Permanent impoundments that meet the requirements of paragraph (a)(3)(ii) of this section and § 780.35(b)(4) of this chapter.

(ix) The placement, in accordance with § 780.35(b)(3) of this chapter, of what would otherwise be excess spoil on the mined-out area to heights in excess of the premining elevation when necessary to avoid or minimize construction of excess spoil fills on undisturbed land.

(2) Minimize the creation of uniform slopes and cut-and-fill terraces. The regulatory authority may approve cut-and-fill terraces only if -

(i) They are compatible with the approved postmining land use and are needed to conserve soil moisture, ensure stability, or control erosion on final-graded slopes; or

(ii) 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.

(3)

as provided in paragraph (k) of this section;

(2) Eliminate all highwalls, spoil piles,

impoundments,

and depressions, except

in the following situations:

(i) You may construct or retain small depressions if -

(A) They are needed to retain moisture, minimize erosion, create or enhance wildlife habitat, or assist revegetation;

(B) They are consistent with the hydrologic reclamation plan approved in the permit in accordance with § 780.22 of this chapter; and

(C) You demonstrate that they will not result in elevated levels of parameters of concern in discharges from the backfilled and graded area.

(ii) The regulatory authority may approve the retention of permanent impoundments if -

(A) They meet the requirements of §§ 816.49 and 816.55 of this part;

(B) They are suitable for the approved postmining land use;

(C) You demonstrate compliance with the future maintenance provisions of § 800.42(c)(5) of this chapter; and

(D) You have obtained all necessary approvals and authorizations under section 404 of the Clean Water Act, 33 U.S.C. 1344, when the impoundment is located in waters subject to the jurisdiction of the Clean Water Act, 33 U.S.C. 1251 et seq.

(iii) You may retain highwalls on previously mined areas to the extent provided in § 816.106(b) of this part.

(iv) You may retain modified highwall segments to the extent necessary to replace similar natural landforms removed by the mining operation. The regulatory program must establish the conditions under which these highwall segments may be retained and the modifications that must be made to the highwall to ensure that -

(A) The retained segment resembles similar landforms that existed before any mining and restores the ecological niches that those landforms provided. Nothing in this paragraph authorizes the retention of modified highwall segments in excess of the number, length, and height needed to replace similar landforms that existed before any mining.

(B) The retained segment is stable. Features that result in the creation of talus slopes for wildlife habitat are acceptable if they meet the requirements of paragraph (a)(3)(iv)(A) of this section.

(C) The retained segment does not create an increased safety hazard compared to the features that existed before any mining.

(D) The exposure of water-bearing strata, if any, in the retained segment does not adversely impact the hydrologic balance.

(4)

as provided in paragraph (h) (small depressions) and in paragraph (k)(3)(iii) (previously mined highwalls) of this section;

(3) 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

.

;

(

5

4) Minimize erosion and water pollution

,

both on and off the site

.

; and

(

6

5) Support the approved postmining land use.

(b) You must return all spoil to the mined-out area. This requirement does not apply to -

(1) Excess spoil

Spoil, except excess spoil disposed of in accordance with

§

§§ 816.71

or §

through 816.74

of this part

, shall be returned to the mined-out area.

(

2) Mountaintop removal mining operations approved under § 785.14 of this chapter. (3) Spoil placed

c) Spoil and waste materials shall be compacted where advisable to ensure stability or to prevent leaching of toxic materials.

(d) Spoil may be placed on the area outside the mined-out area in

non-steep

nonsteep slope areas to restore the approximate original contour by blending the spoil into the surrounding terrain

, provided that you comply with

if the following requirements are met:

(

i) You must remove all vegetation and other organic matter from the area outside the mined-out area before spoil placement begins. You may not burn these materials; you must store, redistribute, use, or bury them in the manner specified in § 816.22(f) of this part.

(ii) You must remove, segregate, store, and redistribute topsoil on the area outside the mined-out area in accordance with § 816.22 of this part.

(c) You must compact spoil and waste materials when necessary to ensure stability or to prevent the formation of acid or toxic mine drainage, but, to the extent possible, you must avoid compacting spoil, soil, and other materials placed in what will be the root zone of the species planted under the revegetation plan approved in the permit in accordance with § 780.12(g) of this chapter.

(d)

(1) You must cover all exposed coal seams with material that is noncombustible, nonacid-forming, and nontoxic-forming.

(2) You must handle and dispose of all other

1) All vegetative and organic material shall be removed from the area.

(2) The topsoil on the area shall be removed, segregated, stored, and redistributed in accordance with § 816.22.

(3) The spoil shall be backfilled and graded on the area in accordance with the requirements of this section.

(e) Disposal of coal processing waste and underground development waste in the mined-out area shall be in accordance with §§ 816.81 and 816.83, except that a long-term static safety factor of 1.3 shall be achieved.

(f) 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 § 816.

89 of this part in a manner that will

41, to prevent sustained combustion,

as approved in the permit in accordance with § 780.12(j) of this chapter.

(3) You must handle all other acid-forming and toxic-forming materials -

(i) In compliance with the plan approved in the permit in accordance with § 780.12(n) of this chapter;

(ii) In compliance with § 816.38 of this part;

(iii) In compliance with the hydrologic reclamation plan approved in the permit in accordance with § 780.22(a) of this chapter; and

(iv) In a manner that will minimize adverse effects on plant growth and the approved postmining land use.

(e) You must dispose of any coal mine waste placed in the mined-out area in accordance with §§ 816.81 and 816.83 of this part, except that a long-term static safety factor of 1.3 will apply instead of the 1.5 factor specified in § 816.81(d)(2) of this part.

(f) You must prepare final-graded surfaces and to minimize adverse effects on plant growth and the approved postmining land use.

(g) Cut-and-fill terraces may be allowed by the regulatory authority where -

(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; or

(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.

(h) Small depressions may be constructed if they are needed to retain moisture, minimize erosion, create and enhance wildlife habitat, or assist revegetation.

(i) Permanent impoundments may be approved if they meet the requirements of §§ 816.49 and 816.56 and if they are suitable for the approved postmining land use.

(j) Preparation of final-graded surfaces shall be conducted in a manner that minimizes erosion and provides a surface for replacement of

soil materials

topsoil that will minimize slippage.

(k) The postmining slope may vary from the approximate original contour when -

(1) The standards for thin overburden in § 816.104 are met;

(2) The standards for thick overburden in § 816.105 are met; or

(3) Approval is obtained from the regulatory authority for -

(i) Mountaintop removal operations in accordance with § 785.14 of this chapter;

(ii) A variance from approximate original contour requirements in accordance with § 785.16 of this chapter; or

(iii) Incomplete elimination of highwalls in previously mined areas in accordance with § 816.106.

[48 FR 23368, May 24, 1983, as amended at 48 FR 41734, Sept. 16, 1983; 81 FR 93392, Dec. 20, 2016; 82 FR 54979, Nov. 17, 2017]