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Soil salvaged under a 1 lift operation was approved in the permit and occurred on 51.6 acres of <br />the 107.9 acres of the Morgan property, prior to February 2008. According to Table 2.04.9 -3 of <br />the permit and data Table 3 (Appendix A attached to this technical review report), 46.7 inches of <br />material was available for salvage on the Morgan property prior to mine disturbance. Based on <br />the field notes from the IRI Order 1 Soil Survey, there was approximately 42 inches of combined <br />A and B soil profiles available for soil salvage. There is a difference of 4.7 inches between <br />OSM's calculation (42 inches) taken from the field notes (Table 3) and the amount (46.7 inches) <br />shown in the permit (Table 2.01.9 -3). According to OSM's analysis (Table 3) and the data <br />found within the permit on Table 2.01.9 -3, it is evident that only about 47% (22 inches) of the <br />46.7 inches of A/B horizon soil materials that were present on the 51.6 acres mined prior to <br />February 2008 were salvaged for use in reclamation. <br />OSM's review of the permitting records indicate that the approval of the MR -51 (2001) and MR- <br />57 (2002) permit revision applications allowed WFC to use overburden referred to as Bench 1 <br />material, as a soil substitute and approved a mixed lift stripping depth of 22 inches on that <br />portion of the Morgan property disturbed prior to February 2008 (see permit text section 2.04.9- <br />28). It is unclear what happened to the remaining 24.7 inches of B horizon material that was <br />previously approved (PR -5 and TR -57) for soil stripping and continues to be approved under PR- <br />6 for salvage (see Table 2.04.9 -3 of the current permit). OSM's review finds that the permit does <br />not account for all salvageable soil material available prior to mining, and particularly those <br />materials that could have been recovered and used to maximize the opportunity to enable the <br />reclaimed prime farmland acreages to reach full yield potential. <br />Table 4 in Attachment A of this report illustrates differences between OSM's calculated salvage <br />depths taken from IRI's Order 1 Soil Survey field notes (total of 50.8 inches) and the depth (total <br />of 58.6 inches) included within the permit for the same area that is to be stripped post - February <br />2008. The difference between the soil recovery depth estimates (7.8 inches) is due to the fact <br />that OSM does not consider the C horizon to be suitable for salvage, whereas the permit <br />approves the C horizon overburden for salvage. As is common practice in prime farmland <br />reclamation across the country, the C horizon is not normally considered for soil salvage and <br />later use in reclamation of prime farmlands since this horizon is not usually subject to soil <br />forming processes and therefore lacks well defined pedological development. In addition, C <br />horizons often consist of parent material and unweathered rock (Cr horizon). According to the <br />limited amount of chemical data included within Table 2.04.9 -2 of the version of the permit that <br />existed prior to that approved with the PR -6 revision, it appears that significant portions of the C <br />horizon exceed the NRCS threshold for calcium carbonate percentage as well as for rock <br />fragment content. Excessive carbonates in the soil can interfere with water movement in the root <br />zone medium and can inhibit plant root uptake of key micro- nutrients, resulting in less than <br />optimal growth. An increase in the rock fragment content of the soil will decrease the water <br />holding capacity of the soil thus increasing the need to irrigate more frequently to maintain <br />adequate plant growth, potentially using additional water resources that could have otherwise <br />been utilized for agricultural benefit elsewhere. Excessive rock content in the plant growth <br />5 <br />