Requirements for Topsoil Removal, Storage and Redistribution

PURPOSE: This rule sets forth the requirements for topsoil removal, storage and redistribution pursuant to sections 444.810 and 444.855.2(5), RSMo. (1) General Requirements. (A) Topsoil and subsoils to be saved under section (2) of this rule shall be separately removed and segregated from other material. (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. (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) Topsoil Removal. (A) Timing. Topsoil shall be removed after vegetative cover that would interfere with the use of the topsoil is cleared from the areas to be disturbed, but before any drilling, blasting, mining or other surface disturbance identified and approved in the permit and plan. (B) Materials to be Removed. All 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. (C) Materials 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. (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. (E) Topsoil Substitutes and Supplements. 1. Selected overburden materials may be substituted for or used as a supplement to topsoil, if in the permit and the plan it is determined that the resulting soil medium is equal to or more suitable for sustaining revegetation than is the available topsoil and the substitute material is the best available to support revegetation. This determination shall be based on— A. The results of 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 may also 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; and B. Results of analyses, trials and tests submitted to the director. Certification of trials and tests shall be made by a laboratory approved by the commission or director, stating that the— (I) Proposed substitute material is equal to or more suitable for sustaining the vegetation than is the available topsoil; (II) Substitute material is the best available material to support the vegetation; and (III) Trials and tests were conducted using standard testing procedures. 2. Substituted or supplemental material shall be removed, segregated and replaced in compliance with the requirements for topsoil under this section. (F) Limits on Topsoil Removal Area. These limits shall be addressed and approved as required to meet 10 CSR 40-3.040, 10 CSR 40-3.090, 10 CSR 40-6.040 and 10 CSR 40-6.050. Where the removal of vegetative material, topsoil or other materials may result in erosion which may cause air or water pollution— 1. The size of the area from which topsoil is removed at any one time shall be limited; 2. The surface soil layer shall be redistributed at a time when the physical and chemical properties of topsoil can be protected and erosion can be minimized; and 3. Other measures shall be taken as approved or required in the permit and plan to control erosion. (3) Topsoil Storage. (A) Topsoil and other materials removed under section (2) of this rule shall be stockpiled only when it is impractical to promptly redistribute this material on regraded areas. (B) Stockpiled material shall be selectively placed on a stable 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. Protection measures shall be accomplished either by— A. An effective cover of nonnoxious quickgrowing annual and perennial plants, seeded or planted during the first normal period after removal for favorable planting conditions; or B. Other methods demonstrated in and approved in the permit and plan to provide equal protection. 2. Unless approved in the permit and plan, stockpiled topsoil and other materials shall not be moved until required for redistribution on a regraded area. (4) Topsoil Redistribution. (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 the surface 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. (B) Topsoil and other material shall be redistributed in a manner that— 1. Achieves an approximate uniform, stable thickness consistent with the approved postmining land uses, contours and surface water drainage system; 2. Prevents excess compaction and/or contamination of the topsoil; and 3. Protects the topsoil from wind and water erosion before and after it is seeded and planted. (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 10 CSR 40-3.120. All soil tests shall be performed by a qualified laboratory using standard methods approved in the permit and plan. AUTHORITY: section 444.530, RSMo 1994.* Original rule filed Oct. 12, 1979, effective Feb. 11, 1980. Amended: Filed July 3, 1990, effective Nov. 30, 1990. Amended: Filed Sept. 15, 1994, effective April 30, 1995. *Original authority 1971, amended 1983, 1990, 1993.