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Reclamation Act (SMCRA). Topsoil was salvaged from subsequently disturbed areas <br />including the sediment pond, riprap stockpile, and office facility areas, and, with the <br />exception of one small area addressed below, will be salvaged from approved disturbance <br />areas where construction has not yet been initiated. <br />Figure 2.2-2 (Surface Facilities Map), shows site specific mapping of soils at an Order I or <br />II level of intensity. The mapping indicates that soils in the vicinity of the sediment pond <br />and riprap stockpile were Rivra Gravelly Sandy Loam Variant, and Nihill Loam, and <br />office facility soils were Glendive Sandy Loam. Soils to be affected by the proposed <br />McClane to Munger haul road are mapped as Glendive Sandy Loam, and a small area of <br />Rivra Gravelly Sandy Loam. A small area to be affected by the proposed realignment of <br />the access road segment at the junction with the state highway is mapped as Havre Loam, <br />saline phase. <br />Twelve (12) to eighteen (18) inches of soil were salvaged from the sediment pond and <br />riprap stockpile area, and 24 inches of soil were salvaged from the office area. <br />Information in Tables 4.4-1 through 4.4-6 documents the suitability of affected soil types <br />by horizon. Upper horizons of the affected soil types are generally good growth media, <br />with the exception of the Havre Loam, which exhibits SAR values in excess of 40, within <br />each sampled horizon below a depth of 1.5 inches. <br />Because no topsoil was salvaged initially, portions of the reclaimed mine bench <br />access/haul road may not be topsoiled upon final reclamation, and the mixed soils and <br />overburden material in the bench and outslopes would be used as plant growth medium <br />for final reclamation. Section 4.4.5.4 summarizes evaluation of the surficial and <br />subsurface bench materials required by the Division through stipulations attached to the <br />1982 and 1985 permit approvals. Analyses submitted in response to the stipulations <br />demonstrated that the material would be suitable for plant growth, and that no special <br />handling would be required. <br />Upon final reclamation, topsoil will be re-spread to a minimum depth of 24 inches in the <br />office area, and 4 to 8 inches on other post-law disturbance areas and approximately 1 <br />acre of the mine bench. Sediment that has been removed from the sedimentation pond <br />during particular sediment cleanout events in the past has been demonstrated to be <br />suitable plant growth material, and has been allowed to be placed in the topsoil stockpile. <br />Pond cleanout material will be approved for use as topdressing on pre-law disturbance <br />areas only upon submittal of chemical and physical analyses demonstrating its suitability. <br />During periods of active mining, coal fines are a significant component of sediment <br />delivered to the pond, and the sediment cleanout material is not a suitable plant growth <br />medium at such times. The following stipulation is necessary. <br />STIPULATION NO. 27 <br />SEDIMENT REMOVED FROM THE SEDIMENT POND MAY BE USED AS A <br />TOPDRESSING OR TOPSOIL SUPPLEMENT PURSUANT TO RULE <br />4.06.2(4)(a), UPON SUBMITTAL OF CHEMICAL AND PHYSICAL ANALYSES <br />DEMONSTRATING THAT THE MATERIAL IS EQUAL TO OR MORE <br />22