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<br />A description of surface water occurrence and mining impacts on surface water <br />within the permit and adjacent areas can be found in the "Probable Hydrologic <br />Consequences of hli ning" section of this document and the "Cumulative Hydrologic <br />Impact Study" document for this mine area. <br />The permit area is drained primarily by the North Fork of the Gunnison River and <br />two ephemeral tributaries to the North Fork. There are no perennial or <br />intermittent streams on the permit area or adjacent to the permit area. The Fire <br />Mountain Canal and the Deer Trail Ditch intersect all overland flow upstream from <br />the permit area. Production of agricultural products at the site is possible <br />only by irrigation. <br />Geoloav-Rules 2.04.5 and 2.04.6 <br />For a description of the geology, refer to Section 2.04.6 in the permit document. <br />Map 2 details [he Geology/Hydrology within the permit and adjacent areas. <br />The rocks exposed in the vicinity of the permit area are the sandstones and <br />shales of the Upper Cretaceous Mesaverde formation, The structure of the <br />sedimentary rocks in the area dips gently to the east. Localized faults and <br />rolls occur as a result of tectonic activity. Due north of the permit area, the <br />Mesaverde formation contains several sequences of coal bearing rocks. The rocks <br />present in the area of the Terror Creek site are of Mancos shale formation. <br />Within the North Fork of the Gunnison River Valley, Quaternary Age alluvial <br />deposits are found. A colluvial deposit in excess of 50 feet thick overlies the <br />Mancos within the permit area and consists of an unconsolidated mixture of large, <br />angular shaped boulders, and rocks and cobbles of various sizes. The <br />unconsolidated material stratigraphically overlies the Mancos shale in the permit <br />area, and since the early 1900s has been graded to its present surface <br />configuration to allow for irrigated agriculture. The unconsolidated and poorly <br />sorted nature of the colluvial material indicates that it was placed by <br />gravitational mass wasting from the adjacent steep slopes. Some transport by <br />overland flow of surface waters is also evident. The unconsolidated nature of <br />the material lends itself to deep weathered zones and infiltration of surface <br />water. <br />Climatological Information-Rule 2.04.8 <br />Information on the climate in the area of the Terror Creek Loadout is detailed <br />in Section 2.04.8 in the permit document. In addition, Exhibit 6 provides data <br />from the weather station in Paonia, Colorado, on average precipitation, <br />temperature, and wind. The wind information was developed for the west Elk Mine <br />site. <br />The climate of the region is typical of the Rocky Mountain area. The valley is <br />semi-arid with annual precipitation averaging about 15 inches per year. The <br />May-September precipitation is 5 inches for the lowlands and 13 inches for the <br />mountain peaks. Temperature extremes at Paonia have ranged from -28°F in January <br />to 100°F during July and August. The average annual temperature is approximately <br />49°F. Snowfall averages 58 inches per year. <br />Terror Creek Loadout Page 5 <br />