2008-03-03_PERMIT FILE - C2006085 (2)

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overlain by the Raton and Poison Canyon formations that are of Upper Cretaceous t;o Early Tertiary Age. Surficial materials tend to be moderately thin over most areas with the exception of localized accumulations in the larger drainage channels. These materials are geographically recent colluvial/alluvial out-wash deposits derived from the combined erosion of the Wet Mountains to the west anti locally present Vermejo and Raton Formation -strata. Exposed sandstone members of the Raton Formation are visible in the higher elevations of the permit area, and form the top of significant and continuous cliff areas due to their resistance to erosion. The Vermejo Formation is underlain by the Trinidad Sandstone which is a massive sandstone considered to be the basal unit in this area. Essentially all of the three types of units described above have the capability to store and transmit water. Each of the strata were evaluated to~ determine if geologic and hydraulic criteria for designation as an aquifer as defined by Rule 1.04 are applicable. Identification of groundwater. aquifers The proposed permit and adjacent areas lie on the flank of the Wet , Mountains, ~~long the east edge of a closed elliptical synclinal basin. This synclin~~l structure runs approximately parallel to the mountain range, termiinating approximately 7 miles to the south. The basin was formed by folding associated with Wet Mountain ,uplift and bordered on the west by the Wet Mountain thrust fault. Known as the Chandler Syncline, it is an asymmetrical structure with a steeply inclined western timt~ and a gradual eastern limb containing the area of interest. ThE: axis of the basin dips from the south end to its low point at the Arkansas River. In the proposed mine area on the eastern- limb, the dip is almost due west at an average slope of 3.3 degrees. The predominate stratigraphic units previously mentioned in the area include surficial colluvial/alluvial deposits, and the Raton, Vermejo, and Trinidad Formations. None of these units contain significant or identifiable Groundwater aquifers. Information regarding aquifers-and groundwateir movement is discussed Exhibit K. All of the formations produce wager to a limited number wells in the area. However, all wells are determined to be completed in poor aquifers generally yielding between one and ten gallons per minute to domestic or stock wells. Water well y-ields are limited by low annual precipitation in the semi- arid climate and because the strata within the Vermejo and Raton formations have very limited lateral continuity. Groundwater stora a and movement in the Vermejo formation is 9 impeded by the types and depositional characteristics of the strata. 2.04-17 Revised 8/20/07