2022-06-13_PERMIT FILE - C1980007 (3)

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West Elk Mine 2.04-128 Rev. 01/94- PR05, 08/94- TR71, 06/95- PR06;02/22- MR460 A current description of the soil series and associations within and adjacent to the permit area is found in Exhibit 27 through Exhibit 29. Mapping Units Twenty-three mapping units were identified in the West Elk Mine study area during the original 1976 soil survey. Characteristics of each unit are summarized in Exhibit 27. The distribution of current SCS and USFS mapping units is shown on Map 40. Table 21 addresses the suitability of the mapping units for reclamation. Due to changes in mapping unit description and nomenclature in the soil surveys from 1976 to 1994, cross-referencing and clarification was necessary. Table 22 identifies and correlates map units from the 1976, 1980 and current soil surveys. Four of the SCS's mapping units occur in the disturbed surface areas. Mapping unit number 31 came before the current SCS mapping unit number 2 - Absarokee - Work loams; mapping unit number 6 came before the current SCS mapping unit number 13 - Beenom-Absarokee Association. Two of the original mapping units, numbers 27 and 400, also occur on the plant site in the S Section 9, T13S, R90W, but due to current mining activity on mapping unit number 27 and the rocky nature of mapping unit number 400, it is highly unlikely that any topsoil stripping will occur in these areas. Field verification of soils information will be conducted prior to construction. If areas of suitable seedbed material are encountered in mapping unit numbers 27 and 400, they will be stockpiled. The SCS soil mapping units are described in Exhibit 28. Soil Sampling and Analysis 1976 Soil Survey Soil analyses were made by the Soil Survey Laboratory, Colorado State University, Fort Collins, Colorado on samples taken from the predominant soils in each of the mapping units during the 1976 soil survey. Only the most predominant and the most representative components of each unit were sampled. The samples taken were composite samples of all the soil horizons occurring in the upper 16 inches of the soil at the sample sites. Exceptions were soils of mapping unit numbers 1, 6, X6, and X38. Mapping unit numbers 1, 6, and X6 are predominately shallow soils. In these units the composite sample was from the surface to the top of the bedrock. Mapping unit number 38 is a deep forested soil and the composite sample was of the upper four feet. The samples represent an average of conditions within the zone of maximum rooting of the most important components of each mapping unit and are not specific for any one major soil horizon. Exhibit 26 presents the results of soil analyses conducted on the original 1976 mapping units for the West Elk Mine study area. 1980 Soil Survey During the 1980 survey, soil samples were collected for analysis in those instances where substantial areas of soil were mapped or when there was a question as to the relative suitability of the mapping unit. Soils were sampled and described by exposing the solum with a shovel and then sampling below this point with a bucket auger. Samples were collected by soil horizon to that depth at which soils appears suitable for topsoiling material. If this depth was questionable, samples were collected below the depth in question to determine the chemistry of this material. Soil sample locations are indicated on Map 41.