30 CFR § 817.22 - Topsoil and subsoil.
(a) Removal. (1)(i) All topsoil shall be removed as a separate layer from the area to be disturbed, and segregated.
(ii) Where the topsoil is of insufficient quantity or of poor quality for sustaining vegetation, the materials approved by the regulatory authority in accordance with paragraph (b) of this section shall be removed as a separate layer from the area to be disturbed, and segregated.
(2) If topsoil is less than 6 inches thick, the operator may remove the topsoil and the unconsolidated materials immediately below the topsoil and treat the mixture as topsoil.
(3) The regulatory authority may choose not to require the removal of topsoil for minor disturbances which—
(i) Occur at the site of small structures, such as power poles, signs, or fence lines; or
(ii) Will not destroy the existing vegetation and will not cause erosion.
(4) Timing. All materials to be removed under this section shall be removed after the vegetative cover that would interfere with its salvage is cleared from the area to be disturbed, but before any drilling, blasting, mining, or other surface disturbance takes place.
(b) Substitutes and supplements. Selected overburden materials may be substituted for, or used as a supplement to, topsoil if the operator demonstrates to the regulatory authority that the resulting soil medium is equal to, or more suitable for sustaining vegetation than, the existing topsoil, and the resulting soil medium is the best available in the permit area to support revegetation.
(c) Storage.
(1) Materials removed under Paragraph (a) of this section shall be segregated and stockpiled when it is impractical to redistribute such materials promptly on regraded areas.
(2) Stockpiled materials shall—
(i) Be selectively placed on a stable site within the permit area;
(ii) Be protected from contaminants and unnecessary compaction that would interfere with revegetation;
(iii) Be protected from wind and water erosion through prompt establishment and maintenance of an effective, quick growing vegetative cover or through other measures approved by the regulatory authority; and
(iv) Not be moved until required for redistribution unless approved by the regulatory authority.
(3) Where long-term surface disturbances will result from facilities such as support facilities and preparation plants and where stockpiling of materials removed under paragraph (a)(1) of this section would be detrimental to the quality or quantity of those materials, the regulatory authority may approve the temporary distribution of the soil materials so removed to an approved site within the permit area to enhance the current use of that site until needed for later reclamation, provided that—
(i) Such action will not permanently diminish the capability of the topsoil of the host site; and
(ii) The material will be retained in a condition more suitable for redistribution than if stockpiled.
(d) Redistribution.
(1) Topsoil materials and topsoil substitutes and supplements removed under paragraphs (a) and (b) of this section shall be redistributed in a manner that—
(i) Achieves an approximately uniform, stable thickness when consistent with the approved postmining land use, contours, and surface-water drainage systems. Soil thickness may also be varied to the extent such variations help meet the specific revegetation goals identified in the permit;
(ii) Prevents excess compaction of the materials; and
(iii) Protects the materials from wind and water erosion before and after seeding and planting.
(2) Before redistribution of the material removed under paragraph (a) of this section, the regraded land shall be treated if necessary to reduce potential slippage of the redistributed material and to promote root penetration. If no harm will be caused to the redistributed material and reestablished vegetation, such treatment may be conducted after such material is replaced.
(3) The regulatory authority may choose not to require the redistribution of topsoil or topsoil substitutes on the approved postmining embankments of permanent impoundments or of roads if it determines that—
(i) Placement of topsoil or topsoil substitutes on such embankments is inconsistent with the requirement to use the best technology currently available to prevent sedimentation, and
(ii) Such embankments will be otherwise stabilized.
(4) Nutrients and soil amendments. Nutrients and soil amendments shall be applied to the initially redistributed material when necessary to establish the vegetative cover.
(e) Subsoil segregation. The regulatory authority may require that the B horizon, C horizon, or other underlying strata, or portions thereof, be removed and segregated, stockpiled, and redistributed as subsoil in accordance with the requirements of paragraphs (c) and (d) of this section if it finds that such subsoil layers are necessary to comply with the revegetation requirements of §§ 817.111, 817.113, 817.114, and 817.116 of this chapter.