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and averages 314 µmhos/cm conductivity and pH of 8.5 on the downstream side of the permit <br />boundary. Water quality across the permit boundary remains fairly constant. <br /> <br />Water quality degrades in Glasier and Meehan Draws as it moves across the proposed permit <br />area. Glasier Draw downstream of the permit boundary exhibits 1641 µmhos/cm average <br />conductivity and an average pH of 7.3; the upstream value is 1362 µmhos/cm conductivity and <br />7.6 pH. Downstream Meehan Draw conductivity is 1286 µmhos/cm, and pH is 7.1; upstream <br />conductivity is 628 µmhos/cm and pH is 8.2. The degradation of water quality in Glasier and <br />Meehan Draws is likely attributed to the leaching of solids from irrigation. <br /> <br />Nygren Draw has an average conductivity of 887 µmhos/cm and a pH of 8.2, and the water <br />quality remains consistent over the short segment that passes through the proposed permit area; <br />conductivity in Tuttle Draw is 1860 µmhos/cm and 8.2 pH. Water quality in Tuttle Draw <br />degrades on the downstream end of the permit boundary, due to irrigation water seepage and <br />spoil spring discharge from the New Horizon #1 Mine. <br /> <br />During high flow from snowmelt, the San Miguel River is a calcium bicarbonate sulfate type. <br />Low flow results in less bicarbonate and greater amounts of calcium and sulfate. Percentages of <br />magnesium, potassium, sulfate and chloride increase as flow progresses downstream. Total <br />Dissolved Solids (TDS) generally varies inversely with discharge and also increases <br />downstream. WFC’s baseline hydrology description notes that the historic water samples taken <br />on the San Miguel River at Naturita have a weighted average TDS value of 316 ppm, with a <br />sodium adsorption ration (SAR) of 0.7, and pH of 8.0 or higher. USGS data for the stretch of the <br />San Miguel River between Nucla and Uravan indicates a weighted average TDS of 396 ppm. <br />The water quality is good for irrigation use year round, but is only suitable for domestic use at <br />higher flows due to increased levels of sulfate at low flow. <br /> <br />Climate – Section 2.04.8 of the permit <br /> <br />The climate of the New Horizon North Mine area is typical of intermountain regions. It is <br />characterized by hot summers, cold winters, low precipitation, and relatively short growing <br />seasons. Climatological information for the area is described in Section 2.04.8 of the permit. A <br />NOAA weather station is located at Uravan, Colorado, approximately 10 miles northwest of the <br />proposed permit area at an elevation of 5,010 feet. The mine receives approximately 12 inches <br />of precipitation in an average year. The majority of the precipitation falls between May and <br />October. The average annual temperature is 53.4° F, and the prevailing wind direction is ESE at <br />7.8 mph. <br /> <br />Soils – Section 2.04.9 of the permit <br /> <br />Peabody Coal Company (Peabody), in 1979, commissioned a formal soil survey of what is now <br />the southern portion of the proposed NHN Mine permit area. With this survey, 16 soil samples <br />were collected from six locations; laboratory analyses are provided in Table 2.04.9-1. Results <br />from stockpile sampling are found in Tables 2.04.9-2 and -3. Much of the area surveyed was <br />subsequently mined by Peabody under the Nucla Mine permit, prior to 1983, and reclaimed. <br />This area presently comprises the New Horizon 1 (NH1) portion (the “Rice tract”) of WFC’s <br /> <br /> <br /> <br />13 <br /> <br />