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The three primary factors affecting soil availability and suitability are previous site disturbance, <br />topographic and physical constrainu on soil salvage, and soil depth and material limitations. Early <br />muting disturbance did not incorporate soil recovery and salvage operations, with the result that <br />available soil resources were lost or mixed with and contaminated by coally materials, coal refuse, and <br />ash. Because of this, there is an inherent soil material shortage and surficial materials in several <br />existing surface disturbance areas maybe unsuitable or marginally suitable due to high coal and coal <br />refuse content. <br />Topographic and physical constrainu which may limit soil recovery include steep sideslopes where <br />safe equipment operations may not be feazible, naturally occurring areaz of surface instability, <br />extensive rocky outcrops, and soils with very high rock fragment content. Relatively thin soils on <br />ridges and steep valley sideslopes and highly variable soil depths represent both a physical soil <br />recovery and a soil suitability limitation since effettive soil recovery while **++~+~*+~>~~g dilution with <br />non-soil materials maybe difficult. Additional soil suitability limitations include high rock fragment <br />content and relatively extensive clay soils. Minor concerns with boron and selenium content were <br />noted for isolated samples but should not genetallyaffea overall soil suitability. <br />Soil Recovery and St_ockoiline <br />As previously noted, soil recovery and stockpiling operations were implemented for all new mining- <br />related disturbance after 1977. Because of soil depth variability, no reasonable documentation is <br />available on average soil recovery depths, although general prattice has involved recovery of all <br />operationally recoverable soils. Similarly, good documentation on soil recovery volumes is not <br />available. At the time that soil recovery operations occurred for the Elk Geek Coal Handling <br />Facilities and Stockpile expansion and West Valley Fill construction activities, documentation of soil <br />recovery volumes for the individual component sub-areaz was not collected. Verifiable <br />documentation is limited to a survey of the Elk Geek Soil Stockpile following completion of soil <br />recovery operations. This survey indicated a stockpile volume of approximately 18,600 cubic yards. <br />Contractor surveys and load counu for the North Elk Geek Soil Stockpile indicate a total volume of <br />approximately 65,200 cubic yards, which includes the volume moved from the Elk Geek Soil <br />Stockpile. Subtratting the Elk Geek Soil Stockpile volume from the total yields a volume of <br />approximately 46,600 cubic yards of soil material recovered from the Elk Geek Mme Surface <br />Facihties Area. Total stockpile volume will be confurtted by ground or aerial survey on completion of <br />construction activities. <br />Table 2.05-ES-Tl, Soil Recovery and Replacement Summary, presents soil recovery and replacement <br />information and estimates based on both verifiable documentation and other information. Breakouu <br />by disturbance area are, in most Gazes, estimates based on the limited historical documentation <br />available and conversations with mine personnel. <br />Soil Replacement <br />Because of the overall soil material shortage, available stockpiled soil materials will be dstributed to <br />maximize revegetation benefiu for the entire mine disturbance area. Because of the material <br />movement distances involved, stockpiled soil resources for individual satellite facilities have been or <br />will be used in reclaiming the associated individual disturbance areas. OMI haz committed to replace <br />approximately 8 inches of soil material on those areas disturbed by construction of the Elk Creek <br />Mute Surface Facilities and will replace 1 foot of soil material on the West Valley Fill Coal Refuse Pile. <br />Remaining available stockpiled soil materiak will be distributed az outlined by Table 2.05-El-Tl, with <br />the priority of placement of a minimum of 6 inches of soil or suitable substitute materials on historic <br />disturbance areas that have been identified as marginally suitable or unsuitable. <br />Soil testing, az described in Section 2.04.9, Soik Resource Information, indicates that some of the <br />undifferentiated mixed soil and refuse materials in the Pre-Iaw disturbance areas generally meet <br />revegetation soil suitability criteria, but may have suitabilitylimitatioru. These areas can effectively be <br />reclaimed through the use of approximately 6 inches of soil material In addition, surficial and near <br />