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medium has the additional negative of reducing the volume of soil available for plant roots to <br />access important nutrients needed for maximizing growth potential and crop yields. <br />For the Morgan property disturbed after February 2008, the currently approved permit authorizes <br />the mixing of B and C horizon materials during the salvage of the 2n lift. Based on the limited <br />data that is available to characterize these horizons, mixing the B and C horizons, has a strong <br />potential to degrade the agricultural quality of the B horizon material and therefore cause the <br />mixed B/C horizon materials to exceed the suitability guidelines for excessive content of <br />carbonates. <br />For the lands disturbed after February 2008, to address minimizing the salvage of C horizon <br />materials having excessive rock content, the permit includes the following statement: "The <br />operators will be trained to evaluate the change where course fragments rise from less thanl0% <br />volume in Lift B to material that has significantly higher coarse fragment (20 -25 %, which is <br />Bench 1) ". For the C horizon materials to be placed below the mixed A/B horizon on the lands <br />disturbed prior to February 2008, the permit includes a threshold for rock content that is to be <br />verified through field sampling by the mine permittee. <br />The C horizon does have similar color characteristics as the B horizons above it and quite often a <br />Cr (rock fragment) horizon is noted. The IRI Order 1 soil survey identified some portions of the <br />C horizon materials as being salvageable for use in reclamation. As used in the original <br />approved permit (PR -5) this survey designated what portion of the C horizon could be salvaged <br />for use as a suitable plant growth material. The Cr horizon was not included in this survey as a <br />layer that was suitable for salvage. According to IRI's field notes, salvageable material for the C <br />horizon varied in depth from 6 inches in some locations to 34 inches in other locations of the <br />Morgan property (Table 5, Attachment A). <br />OSM's review finds that relying on the chemical analysis taken from only 2 test pit <br />locations is insufficient data for determining that the C horizon is suitable for salvage and <br />redistribution; and that use of these soil materials will not likely inhibit plant growth or <br />reduce the water holding capacity of the reclaimed soil (4.25.4(1)(a) and (b)). Colorado <br />Rule 2.04.9(1) (a) contains the following language: "Description, sampling and analysis of <br />soil horizons in sufficient detail to determine the horizons suitable for salvage ". OSM's <br />review finds that the permit lacks sufficient detail to determine that the C horizon is <br />suitable for salvage and use in prime farmland reclamation; therefore the permit is not in <br />accord with the requirements of the regulations at 2.04.9(1). <br />Prime Farmland Reclamation Practices and Permitted Topsoil/Subsoil Handling Plans <br />Within the approved permit WFC is authorized to redistribute soils on the Morgan property <br />within 4 individual zones. Zones 1, 2, and 3 were disturbed prior to February 2008, while Zone <br />4 was disturbed after the state began requiring two separate lifts during soil salvage operations. <br />6 <br />