2013-11-04_PERMIT FILE - C1981022A (4)

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1.0 INTRODUCTION This revegetation plan is designed to restore the physical landscape disturbances associated with the development and operation of the Somerset Mine (now sealed), the Sanbom Creek Mine and the Elk Creek Mine. C+perations in the Somerset Mine began in 1902 and continued until 1985. In 1991, Somerset Mining Company opened the Sanborn Creek Mine. Oxbow Mining, LLC (OMLLC) (formerly dba as Somerset Mining Company) is proceeding with development of the Elk Creek Mme. Approximately 72 acres of disturbance (historic figure for Somerset and Sanbom Creek Mine -See Table 2.05-T1 for currem disturbance acreages) are associated with the surface plant facilities, mule portals, power line roads, and other minor disturbances. These disturbances, which occur on both private and federal land, will continue for the life of the mine. The disturbance affects two major vegetation types, Mountain Shrubland and Juniper Woodland. Topsoil was not salvaged during the early construction ("pre-law" or prior to SMCRA) activities at the minesite. Therefore, revegetation will be initiated on surface soils produced by regrading existing surface materials. By the time revegetation activities occur in the future, it has been assumed that areas of old shale materials from pre-law refuse piles will be weathered to a consistency similar to the other materials to be revegetated at the Somerset, Sanbom Creek and Elk Creek Mines. Analytical results from seventeen surface soil collections in disturbed and undisturbed azeas provide an indication of the suitability of surface materials as a medium for plant growth. These data, as analyzed by Ford Chemical Laboratories on August 8, 1980 indicated that there are no problems with salts. Conductivity and sodium adsorption ration (SAR) values are all below the conservative limits of 4000 umhos/cm and 6, respectively (see WRDC 1981). The data on heary metals aze total values derived from acid ex[raction and thus cannot be compared to most standards for reclamation suitability (see Shafer 1979, WDEQ 1981). If samples for undisturbed areas are compared with those from disturbed locations, it is apparent that total heavy metal levels are comparable throughout for boron, cadmium, copper, iron, lead, manganese, mercury, molybdenum, nickel, and selenium Again however, note that the data examined were acid extractable totals and not plant-available levels. Data for heavy metals are not in a form to evaluate the hazard for plant growth. However, total heavy metals in disturbed materials and undisturbed soils aze not significantly different. In the case of soil [exture the 17 samples had a reported texture of either "sandy loam" or "cla}~'. However, this classification was produced without a particle size analysis. The occurrence of numerous samples in two diverse textural classification and the absence of intemrediate textural ranges suggest an imprecise determination. Therefore, the soil textural data may not represent sufficiently precise deternruiation to merit serious evaluation as to their suitability for reclamation. During 1986, soil sample sites for the lower Elk Creek facilities were sampled. These results indicated the soil on the north storage yard is acceptable for revegetation. Other areas of the lower Elk Creek facilities require six inches of suitable root zone material. In 1987, soil test pits were dug on the west bench, central yard and east bench areas. The results are tabulated in Table 1. These test pits confirm the need for 6 inches of topsoil for the central yard area and east bench. The west bench area appears to have sufficient subsoil for revegetation. The coal material layer is generally less than 6 inches thick This gob material will either be scarified and mixed with underlying material prior to topsoil placement or scraped up by mobile equipment for use as fill material. TR 40 H-1 Revised August 2002