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-5- There are three ma,~or bedrock aquifers within the mine area; the Upper Sandstone, the Middle Sandstone, and the Rollins Sandstone. These are regional aquifers and are relatively thick and laterally extensive throughout the mine area. The Rollins sandstone is below the lowest coal seam to 6e mined ("A" seam") and is within the Iles Formation. The "A" coal seam, the Middle sandstone and the Upper sandstone all lie within the Bowie member of the Williams Fork Formation. The Anderson coal seam lies within the Paonia member. The North Thompson Creek No. 1 Mine is to the "A" seam, while the No. 3 Mine is in the Anderson seam. In addition to •t he sandstone aquifers mentioned above, several other potential Sandstone aquifers exist above and below the Anderson seam. However, these sandstones are thin and laterally discontinuous. An alluvial aquifer exists on portions ad,Jacent to North Thompson Creek. However, this aquifer 15 shallow and very discontinuous. The loadout site, located adjacent to the Roaring Fork River, is situated on an ancient valley floodplatn. The alluvium ad,Jacent to the river at this point is laterally extensive with thicknesses from 50 to 100 feet in many areas. The alluvial aquifer along the Roaring Fork River has good quality water. Historically, agricultural communities in the Roaring Fork Valley have produced cattle, sheep and hay. Today, however, sheep production is extremely limited and, on a relative scale, cattle are now the only significant agricultural commodity exported from the Valley. Other land uses in this region are recreation, timber production, and mining. Recreational uses are seasonal, including skiing in winter, hunting 1n fall, and fishing, camping, river rafting and backpacking in summer. The Roaring Fork Drainage Basin has become a popular location for vacation homes and condominiums, this due in part to the skiing, recreation, and tourism which is popular in the area. Topsoil in the Thompson Creek drainage is limited. Only a thin veneer of topsoil exists on the steep sideslopes of the ridges. Furthermore, much of the topsoil at the mine facility area was lost through historic mining disturbances. In contrast, the loadout site was built on a wide valley floor where topsoil was rich, thick and extenslve. Since the loadout was recently constructed, all available topsoil has been salvaged. The mine permit area is characterized by five vegetation types: riparian woodland, mountain shrubland - dry and moist phase, aspen forest and spruce-fir forest. Riparian woodland is prevalent along the Thompson Creek streambanks and its tributaries ad,~acent to the mine area. ,~~ The loadout vegetation communities are primarily introduced species for grazing and haying purposes. However, pinyon-juniper woodland, riparian woodland, big sagebrush shrubland and rabbttbrush shrubland are also found to and ad,)acent to the loadout site.