_GENERAL DOCUMENTS - C1981017 (258)

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The elevation of the toe of each Outslope is somewhat variable. Most of the Outslope toes are located at elevations between 9,100 and 9,600 feet. All of the Project work will be accomplished between elevations 9,100 and 10,100. The aspect of each Mine Bench Outslope is to the south or south east. Due to the southerly aspect and the black color of the surface materials, the surface temperature of Outslopes is very hot during the summer months. The Mine Bench Outslopes are complex slopes with variations of slope angle at each slope. Slope angles have been measured from between 68% to 78%, with an average slope angle of 74%. Dominant Land Form The Project will take place within Coal Basin. Coal Basin is a large mountain basin located on the easterly flank of the Grand Hogback, immediately north of the West Elk Mountains. The Mine Bench Outslopes, which collectively comprise the Project Area, are man made features created in the late 1950's through the mid 1960's. The features were created as ridgelines projecting eastward from the north —south trending Huntsman Ridge, and were excavated to provide access to the coal seams of interest. The overburden and waste coal material excavated from the ridge lines was cast down the ridge sides forming long, steep unconsolidated slopes. Following mine development, trommel reject and other run-of-mine waste were added to the Outslopes. Very little vegetation has volunteered onto the slopes. The predominant species which currently exist on the slopes are reclamation species introduced as part of revegetation tests conducted by the Division of Minerals and Geology. The unconsolidated materials which form the Mine Bench Outslopes are subject to high rates of erosion, and to soil creep processes. The Outslopes are characterized by numerous large gullies interspersed with smaller rills. The rills and gullies are active following snow melt and summer rain storm runoff. Surficial creep of the Outslope material has been observed to occur. Creep in areas vegetated as part of demonstration test plots appears to be less than at unvegetated areas. No wetlands occur on the Outslopes. The toe of the Mine 3 Outslope, at the lower road remnant crossing, is seasonally wet, as a result of seep(s) emanating from the contact of the Outslope materials with the underlying bedrock materials. Infrequent willows are observed uphill of the Outslope toe, adjacent to the road remnant, and some distance downhill, below the road remnant fill slope. This area is not believed to be a wetlands. The Project hopes to take advantage of the moist conditions in this area by planting it with shrubs to act as natural sediment barriers. Condition of Land The Mine Bench Outslopes are heavily gullied, and support little vegetation. Volunteer species are generally limited to Calamagrostis purpurascens and Senecio atratus. It is estimated that the total cover afforded by the combination of both species is less than five percent (5%). As a result of the paucity of vegetation, erosion of the Outslopes is significant. Sediment generated from the Outslopes is thought to contribute to the overall iron loading of Coal Creek.