PURPOSE: This rule sets forth the requirements for topsoil removal, storage and redistribution pursuant to sections 444.810, 444.855.2(5) and 444.860, RSMo.

1. (1) General Requirements.

   1. (A) Before disturbance of areas affected by surface operations, topsoil and subsoils to be saved under section (2) of this rule shall be separately removed and segregated from other material.
   2. (B) After removal, topsoil shall either be immediately redistributed, as required under section (4) of this rule, or stockpiled pending redistribution, as required under section (3) of this rule.
   3. (C) Topsoil and subsoils to be saved under section (2) of this rule shall be removed twenty-five feet (25') in advance of mining, unless otherwise stated in the permit.

2. (2) Topsoil Removal.

   1. (A) Timing. Topsoil shall be removed from surface areas to be affected by underground or major structures, after vegetative cover that would interfere with the use of the topsoil is cleared from portions of those areas that will be disturbed, but before any drilling for blasting, mining or other disturbance of surface lands.
   2. (B) Materials to be Removed. Topsoil shall be removed in a separate layer from the areas to be disturbed, unless use of substitute or supplemental materials is approved in the permit and plan in accordance with subsection (2)(E) of this rule. If use of substitute or supplemental materials is approved, all materials to be redistributed shall be removed.
   3. (C) Material to be Removed in Thin Topsoil Situations. If the topsoil is less than six inches (6"), a six-inch (6") layer that includes the A horizon and the unconsolidated materials immediately below the A horizon, or the A horizon and all unconsolidated material if the total available is less than six inches (6"), shall be removed and the mixture segregated and redistributed as the surface soil layer, unless topsoil substitutes are approved in the permit and plan pursuant to subsection (2)(E) of this rule.
   4. (D) Subsoil Segregation. The B horizon and portions of the C horizon, or other underlying layers demonstrated to have qualities for comparable root development, shall be segregated and replaced as subsoil, if the permit and plan requires that either of these is necessary or desirable to ensure soil productivity consistent with the approved postmining land use.

   5. (E) Topsoil Substitutes and Supplements.

      1. 1. Selected overburden materials may be

substituted for, or used as a supplement to, topsoil, if in the permit and plan, it is determined that the resulting soil medium is equal to or more suitable for sustaining the vegetation than is the available topsoil and the substitute material is the best available to support the vegetation. This determination shall be based on the results of—

1. A. Chemical and physical analyses of

overburden and topsoil. These analyses shall include determinations of pH, net acidity or alkalinity, phosphorus, potassium, texture class and other analyses as required in the permit and plan. It also may be required in the permit and plan that results of field-site trials or greenhouse tests be used to demonstrate the feasibility of using these overburden materials; or

1. B. Analyses, trials and tests shall be

submitted to the director. Certification of trials and tests shall be made by a laboratory approved by the commission or director stating that the—

1. (I) Proposed substitute material is

equal to or more suitable for sustaining the vegetation than is the available topsoil;

1. (II) Substitute material is the best

available material to support the vegetation; and

1. (III) Trials and tests were conduct-

ed using standard testing procedures.

1. 2. Substituted or supplemented material

shall be removed, segregated and replaced in compliance with the requirements for topsoil under this section.

1. (F) Limits on Topsoil Removal Area. Where the removal of vegetative material, topsoil or other materials may result in erosion which may cause air or water pollution—

   1. 1. The size of the area from which top-

soil is removed at any one time shall be limited;

1. 2. The surface soil layer shall be redis-

tributed at a time when the physical and chemical properties of topsoil can be protected and erosion can be minimized; and

1. 3. Other measures shall be taken as

approved or required in the permit and plan.

1. (3) Topsoil Storage.

   1. (A) Topsoil and other materials removed under section (2) of this rule shall be stockpiled only when it is impractical to promptly redistribute these materials on regraded areas.

   2. (B) Stockpiled materials shall be selectively placed on a stable surface area within the permit area, not disturbed and protected from wind and water erosion, unnecessary compaction and contaminants which lessen the capability of the materials to support vegetation when redistributed.

      1. 1. Protection measures shall be accom-

plished either by—

1. A. An effective cover of nonnoxious,

quick-growing annual and perennial plants, seeded or planted during the first normal period after removal for favorable planting conditions; or

1. B. Other methods demonstrated to

and approved in the permit and plan to provide equal protection.

1. 2. Unless approved in the permit and

plan, stockpiled topsoil and other materials shall not be moved until required for redistribution on a disturbed area.

1. (4) Topsoil Redistribution.

   1. (A) After final grading and before the replacement of topsoil and other materials segregated in accordance with section (3) of this rule, regraded land shall be scarified or otherwise treated as required in the permit and plan to eliminate slippage surfaces and to promote root penetration. If the person who conducts underground mining activities shows, through appropriate tests, and the commission or director approves, that no harm will be caused to the topsoil and vegetation, scarification may be conducted after topsoiling.

   2. (B) Topsoil and other materials shall be redistributed in a manner that—

      1. 1. Achieves an approximate uniform,

stable thickness consistent with the postmining land uses, slopes and surface drainage system;

1. 2. Prevents excess compaction of the

topsoil; and

1. 3. Protects the topsoil from wind and

water erosion before and after it is seeded and planted.

1. (5) Topsoil Nutrients and Soil Amendments. Nutrients and soil amendments in the amounts determined by soil tests shall be applied to the redistributed surface soil layer so that it supports the approved postmining land use and meets the revegetation requirements of rule 10 CSR 40-3.270. All soil tests shall be performed by a qualified laboratory using standard methods approved in the permit and plan.

AUTHORITY: section 444.810, RSMo 1994.* Original rule filed Aug. 8, 1980, effective Dec. 11, 1980. Amended: Filed July 3, 1990, effective Nov. 30, 1990. *Original authority 1979, amended 1983, 1993.