2017-08-16_REVISION - C2010089 (2)

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11 The San Miguel River, with a drainage area of 1,080 square miles, derives the majority of its flow from snowmelt runoff. Mean flow at Naturita for water years 1995-2009 is 247 cfs. The USGS station at Uravan has a mean flow of 358 cfs for water years 1954-2011. At Nucla, the mean is 246 cfs for water years 1995-2011. During irrigation season, roughly mid-April to early October, the CCC Ditch diverts approximately 100 cfs from the San Miguel River just upstream of the town of Naturita, so lower flows are experienced during the latter part of the irrigation season. The ditch is used primarily for flood irrigation of the Tabeguache plateau area, which includes the permit area. As mining operations move to the north, the ditch will be replaced by a permanent pipeline. WFC has conducted baseline water monitoring on twenty surface water sites within and adjacent to the permit boundary. In addition to the monitoring conducted by WFC, Peabody Coal Company conducted baseline monitoring in the early 1980’s prior to mining in what is now the southern portion of NHN. WFC has also collected surface water data on Tuttle Draw for it is adjacent to the Mine 2 area at the New Horizon Mine. Maps 2.04.5-1, 2.04.7-1, and 2.04.7-10 of the permit application package depict all of the surface water monitoring sites. Baseline data on the 2nd Park Lateral and Tuttle, Nygren, Meehan and Glasier Draws have been collected (monthly field parameters and bi-monthly laboratory analysis) since October 2008 and are available in Appendix 2.04.7-2. Climate- Section 2.04.8 of the permit The climate of the NHN area is typical of intermountain regions. It is characterized by hot summers, cold winters, low precipitation, and relatively short growing seasons. Climatological information for the area is described in Section 2.04.8 of the permit. A NOAA weather station is located at Uravan, Colorado, approximately 10 miles northwest of the permit area at an elevation of 5,010 feet. The mine receives approximately 12 inches of precipitation in an average year. The majority of the precipitation falls between May and October. The average annual temperature is 53.4° F, and the prevailing wind direction is ESE at 7.8 mph. Soils - Section 2.04.9 of the permit The applicant conducted a detailed baseline soil survey of the entire NHN Mine permit area in 2008. For this effort, a total of 183 backhoe pits were dug, located as shown on permit Maps 2.04.9-2 and -3. Of these, 118 pits were dug at locations undisturbed by mining activities, while 65 were located within the area disturbed and reclaimed by Peabody. At each undisturbed location, a formal soil pedon description was taken. The completed pedon forms are found in Appendix 2.04.9-1. Each pit was photographed, and 28 samples from 11 sites were collected for laboratory analysis. Table 2.04.9-6 lists the chemical and physical properties of those samples. For test pits located in the disturbed and reclaimed area, only depths of topsoil to be salvaged were noted. WFC has mapped eight soil units in the NHN permit area: Aquolls, 0 to 3% slopes; 77 Pinon, 3 to 12% slopes; 78 Pinon, 5 to 30% slopes; 78 Ustic Torriorthents, 5 to 30% slopes; 81 Progresso loam, 3 to 6% slopes; 82 Progresso loam, 6 to 12% slopes; and Rock Outcrop-Orthents Complex, 40-90% slopes. Soils redistributed upon the reclaimed Peabody disturbance are mapped as REC.