2014-06-20_REVISION - M1981207 (10)

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Blue Pit 112 Permit Amendment Exhibit I - Soils Information The soil survey performed by the NRCS covers the permit area. The soil mapping is shown on the Exhibit B Map. The associated soil type descriptions are listed below. Soils encountered on the site were comprised entirely of Empedrado loams as mapped by the NRCS. These soils ranged from 2 -6% slope and are deep, well- drained soils with moderate permeability and high water capacity. Surface runoff is medium and erosion hazard is slight on the Empedrado soils. These soils are well- suited for bay production, small -grain crops and pasture. Records indicate this soil type can annually yield 5 tons bay /acre or go bushels of barley /acre under proper management. It has few limitations, but performs best if a crop residue is left covering the field over the winter and with adequate fertilizer added annually. An existing topsoil stockpile is located at the eastern edge of the current disturbance area, as shown on Maps C -i, C -2A and C -213. This pile contains approximately 104,000 cubic yards and is located within Area 1. This material will be used to reclaim Mining Area 1 once final grade is achieved. The excess topsoil from Area 1 will be used for Area 2, which is deficient in topsoil. Table 6: Topsoil Volumes 64.57 109,013 138,261 65.91 110,073 106,335 4.20 7,092 6,776 134.68 226,178 251,372 The existing disturbance of Mining Area 1 requires 109,013 cubic yards of topsoil for reclamation based on the restored thickness of 12 inches. The volumes for all areas are shown in Table 6. The excess will be used in other areas. Additional topsoil stockpiles will be located in the pit as it is expanded. Additional area to the north of the existing excavation may be used to temporarily store the topsoil from the expansion area that cannot be directly placed on backfilled areas, Overburden will continue to be stripped in advance of the mining operation. Its thickness varies from 2 feet to 10 feet but it is expected to average 4 feet over the entire expansion area. Since there is a significantly lesser amount of topsoil and overburden compared to gravel, the topsoil /overburden stripping will only be needed a few days per year. Topsoil will be stockpiled for the initial period until the mining operation has progressed far enough for reclamation to start. This is expected as mining transitions to Mining Area 2. Once areas are ready for reclamation, the stripped topsoil will be directly placed in these areas. Overburden will always be directly placed because there are areas currently ready for overburden placement and this will continue until the end of mining. The topsoil will be removed with a loader or excavator at the existing ground level. The material will be loaded into trucks and hauled to the topsoil stockpile or areas ready for reclamation. The overburden will also be removed with a loader or excavator at near the existing ground level. The Blue Pit May 2014 I -1