2006-12-12_REVISION - M1987028 (2)

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RECEIVE EXHIBIT I--- SOILS INFORMATION DEC 12 2006 Division of Reclamation, Mining a d S f ry Site investigation of soils type and availability reflect a wide range oinso~~ ti~ickness depending on location and slope. Soils present reflect a dark, almost black organic rich surface layer 0-6" with a course, rocky component. Soil is gravelly, with angular rock fragments grading to a very rocky component as one moves downward in the soil horizon. Soils viewed above the highwall support alpine grasses, forbs, lodgepole pine., Douglas fir, Engleman spruce, and aspen stands and can be as much as six feet thick in localized areas. Other zones of exposed soil along the highwall contact reflect soil thickness at about one foot and quickly grading to highly angular sub-soil and fractured bedrock within 3 feet from surface. Thick soil horizons aze also evident in localized areas along the Taylor Gulch drainage channel, where tree growth has protected soils from erosion and transport from the bottom of the basin by storm events or seasonal snow melt run-off. Soil occurrence over the marble bed is variable, with a zone (2-3 acres max.) of thicker soil (possibly 1-2') for a short distance just north of the present disturbance, followed by an azea of little to no soil covering the marble bedrock outcrop as it is followed to the northern end of the affected land area. Past alpine glaciation may have removed volumes of soil at the head of Taylor Basin, reflected in the lack of soil horizon in this area as compared to the slopes flanking the basin. Soils north of the currently disturbed lands are very rocky, with large (12") angular rocks exposed on the surface and mixed with float material from igneous and metamorphic bedrock exposed at the ridgeline'/ mile or more above the western affected land boundary line. In general, site soil characteristics reflect high organic material content within the first six inches of surface, course textures with high percolation potentials, albeit fair to good moisture retention characteristics. Soils appeaz to support a variety of alpine vegetation including grasses, forbes, and tree species and do not appeaz to be a limiting factor in regards to nutrient source nor volume of soil available for re-vegetation of disturbed azeas. United State Forest Service soils surveys show three soil types mapped at this site, the Howardville family soil type found in the bottom areas neighboring Taylor Gulch and the mine site, Howazdville-Leighcan families complex, occurring over the southern portions of the affected lands primarily within the heavily timbered areas south and west of the mining zone, and Moran family-Rock outcrop-Teewinot family complex, found on the western slope of Taylor Basin north and west of the mining zone. Future mining progress will incur primarily Moran family type soils. Amore detailed discussion of soils follows from appropriate sections of the 2005 Draft of the USFS Northern San Isabel and Western Pike National Forest Soil and Ecological Land Unit Survey: 21