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laterally extensive throughout the mine azea. The Rollins Sandstone is below the lowest coal seam that was 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 in the A seam, while the No. 3 Mine is in the Anderson seam. There was some development work in the B seam at the No. 1 Mine. In addition to the sandstone aquifers mentioned above, several other potential sandstone aquifers exist above and below the Anderson seam. However, these sandstones are thin and laterally discontinuous. A shallow and discontinuous alluvial aquifer exists on portions of the permit area adjacent to North Thompson Creek. The loadout site, located adjacent to the Roaring Fork River, is situated on an ancient valley floodplain. The alluvium adjacent to the river at this point is laterally extensive with thicknesses from 40 to 50 feet. Surface Water Hvdroloev Two perennial streams are in the mine site permit azea: North Thompson Creek and Middle Thompson Creek. The watersheds of both drainages aze very similaz. Elevation ranges from 7,600 feet at the azea of the former mine office to over 11,000 feet in the headwater. Stream flow on North Thompson and Middle Thompson Creeks is derived primarily from snowmelt. Flows resulting from snowmelt typically have a gradual rise, moderate peak, lengthy recession and lazge volume. The peak occurs in May or June, while base flow is in late fall or winter. All surface disturbances at the mine site aze in the North Thompson Creek drainage, except for small azeas associated with a ventilation adit, a ventilation shaft, and two water monitoring flumes located in the Middle Thompson Creek drainage. Underground workings of the No. 1 Mine extend from entrance portals in the North Thompson Creek drainage south into the Middle Thompson Creek drainage. The underground workings for the No. 3 Mine are entirely within the North Thompson Creek drainage. All surface disturbances at the loadout site are in the Roaring Fork River drainage basin. Climate Annual precipitation at the mine is approximately 22 inches, with upland azeas receiving up to 35 inches. Approximately 65 percent of the annual precipitation occurs as snowfall. Vegetation Five vegetation types characterize the mine site: ripazian woodland, mountain shrubland -dry and moist phase, aspen forest, and spruce-fir forest. Riparian woodland is prevalent along the Thompson Creek stream banks and its tributaries adjacent to the mine area. The loadout vegetation communities are primarily introduced species for grazing and haying purposes. However, pinon juniper woodland, riparian woodland, big sagebrush shrubland, and