Section 312 IAC 25-6-11 - Surface mining; topsoil and subsoilAuthority: IC 14-34-2-1
Affected: IC 14-34
Sec. 11.
(a) All topsoil shall be removed as a separate layer from the area to be disturbed and segregated. Additional topsoil requirements are as follows: (1) Where the topsoil is of insufficient quantity or of poor quality to sustain vegetation, the material approved by the director as a topsoil substitute or supplement in accordance with subsection (c) shall be removed separately from the area to be disturbed and segregated.(2) If the topsoil is less than six (6) inches thick, the permittee may remove the topsoil and the unconsolidated materials immediately below the topsoil to a total depth of six (6) inches and treat the mixture as topsoil.(3) Topsoil need not be removed: (A) at sites disturbed only by power poles, signs, fence posts, electrical substations, transformers and switchboxes, explosives magazines, temporary buildings on skids, topsoil stockpiles, culvert installations, cable routes, cable storage areas, powerline cable suspension towers or "horses", pumps, pump hoses, and pipelines; and(B) with the director's approval, for minor disturbances that will not permanently destroy the existing vegetation and will not cause erosion.(b) All material to be removed under this rule shall be removed after the vegetative cover that would interfere with its removal and use is cleared from the area to be disturbed, but before any drilling, blasting, mining, or other disturbance, except those disturbances described in subsection (a)(3), takes place.(c) Selected overburden materials may be substituted for, or used as a supplement to, topsoil if the operator demonstrates to the director in the permit application that the resulting soil medium is equal to or more suitable for sustaining vegetation than the existing topsoil.(d) Storage requirements are as follows:(1) Materials removed under subsections (a) and (f) shall be segregated and stockpiled when it is impractical to redistribute such materials promptly on regraded areas within the permit area.(2) Stockpiled materials shall: (A) be selectively placed on stable sites within the permit area or within other bonded permit areas of the same permittee within the same mining operation;(B) be protected from contamination and unnecessary compaction that would interfere with revegetation;(C) be protected from wind and water erosion through prompt establishment and maintenance of an effective, quick growing nonnoxious vegetative cover, or through other measures approved by the director in the permit application; and(D) not be moved until required for redistribution unless approved by the director in the permit application.(3) Where long term surface disturbances will result from facilities such as support facilities and preparation plants and where stockpiling of materials removed under subsection (a) would be detrimental to the quality or quantity of those materials, the director may, in the permit application, approve the temporary distribution of the soil materials removed on an approved site within the permit area or another permit area of the same permittee within the same mining operation to enhance the current use of that site until needed for later reclamation, provided that: (A) such action will not permanently diminish the capability of the topsoil of the host site; and(B) the material will be retained in a condition more suitable for redistribution than if stockpiled.(e) Redistribution requirements are as follows:(1) Topsoil materials removed under subsection (a) shall be redistributed in a manner that: (A) achieves an approximately uniform, stable thickness consistent with the approved postmining land use, contours, and surface water drainage systems;(B) prevents excess compaction of the materials; and(C) protects the materials from wind and water erosion before and after seeding and planting.(2) Before redistribution of the materials removed under subsections (a) and (f), 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) Redistribution of topsoil or topsoil substitutes on the approved postmining embankments of permanent impoundments or of roads shall not be required if the permittee demonstrates that: (A) placement of such materials on the embankments is inconsistent with the requirement to use the best technology currently available to prevent sedimentation; and(B) the embankments will be otherwise stable against erosion.(4) Nutrients and soil amendments shall be applied, in amounts determined by soil tests using standard agronomic laboratory procedures, to the initially redistributed material when necessary to establish vegetative cover.(f) The director may require that portions of the subsoil be removed and segregated, stockpiled and redistributed as subsoil in accordance with the requirements of subsections (d) and (e) if he finds such subsoil layers are necessary to comply with the revegetation requirements of this rule. Natural Resources Commission; 312 IAC 25-6-11; filed Jun 21, 2001, 2:53 p.m.: 24 IR 3512, eff Dec 1, 2001; readopted filed May 29, 2007, 9:51 a.m.: 20070613-IR-312070146RFA; readopted filed Sep 19, 2013, 10:12 a.m.: 20131016-IR-312130125RFAReadopted filed 3/26/2019, 3:40 p.m.: 20190424-IR-312190011RFA