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transmission. As a result of this review, the soils in the Dawson Mine project were <br /> conservatively classified as group "D" soils, which are the least permeable soils in the NRCS <br /> hydrologic group system. Group "D" soils are considered to have a very slow infiltration rate <br /> and very slow rate of water transmission. <br /> Climate <br /> Fremont County, Colorado averages 13 inches of rain, and averages 44 inches of snow per <br /> year. On average, there are 260 sunny days per year. The summer high is around 89 degrees, <br /> and the winter low is around 16 degrees. <br /> Site Impacts <br /> Surface water flows leaving the project site will be controlled and released to match historical <br /> 10-year and 100-year storm levels using a detention/sedimentation pond and an outlet structure <br /> at the north end of the topsoil stockpile area. The increased water now caused from adding <br /> gravel areas such as roads, the adit/plant pad, maintenance pad, and low permeable buildings <br /> have been calculated and will be reduced to meet historical flow rates at the detention pond <br /> location. <br /> Three (3) areas have been defined for the project. These areas were broken into numerous <br /> water basins based on topography and proposed design requirements. Basin delineations are <br /> shown on Sheet SW 1 and Table 1.0 below summarizes each area and basin. Site impacts for <br /> these areas are described in the sections that follow. <br /> Table 1—Water Basin Summary Table <br /> Area Basin Area Impacted Facility <br /> Mark (acres <br /> Offsite Stormwater Al 30.57 Channel A <br /> A2 28.39 Channel A <br /> DI 8.83 Culvert 4 Channel C, Det. Pond <br /> D2 9.20 Culvert 3, Channel C, Det. Pond <br /> D3 2.92 Culvert 2, Channel C, Det. Pond <br /> D4 2.55 Road B Ditch <br /> E 207.03 Culvert 6, Culvert 7 <br /> Operations Area B 8.38 Channel B, Contact Water Pond <br /> Onsite Stormwater C 9.23 Laydown, Stockpiles, Channel C, Det. Pond <br /> F 8.84 Access Road <br /> Offsite Stormwater Impacts (Basins Al, A2, D1, D2, D3, D4, and E) <br /> Southern Boundary Offsite Flows (Basins Al and A2)— Water generally flows <br /> downward to the southern edges of the project after a storm event from the ridges running N <br /> up to and including Dawson Mountain. Basins Al, A2 and E were defined in this analysis o <br /> to determine 10-year and 100-year 24-hour surface water flows. These flows were then o <br /> used to design Channel A, which diverts water around the tailings and operations area into <br />