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• SECTION 3 - RESULTS AND DISCUSSION <br />The Lorencito Canyon Mine is located on tributaries south of the Purgatoire River, <br />2.7 miles east of Weston, Colorado. The headwaters of the Purgatoire are located <br />eighteen miles west of the permit area, and the river is draining 403.7 square miles <br />of watershed at its confluence with Lorencito Canyon. The Purgatoire is a tributary <br />of the Arkansas River. Predicted average annual precipitation is shown by Table 3-1 <br />Average Annual Precipitation. The Loadout is located at 6615 feet; the area of <br />active mining at 7200 to 7600 feet. Precipitation in the 2008 calendar year was <br />about 80% of average for the year with the majority of precipitation occurring in <br />August. <br />Table 3-1 <br />ANNUAL PRECIPITATION - LORENCITO CANYON MINE <br />Month 6600 Feet Elevation 7200 feet Elevation <br /> Precipitation Snow Precipitation Snow <br /> (inches) (inches) (inches) (inches) <br />JAN 0.53 5.6 0.64 6.1 <br />• <br />FEB 0.6 6.7 0.71 7.5 <br />MAR 1.02 10 1.19 11.9 <br />APR 1.19 6.9 1.34 8.4 <br />MAY 1.96 2 2.03 2.4 <br />JUN 1.45 0.1 1.44 0.1 <br />JUL 2.43 0 2.71 0 <br />AUG 2.27 0 2.46 0 <br />SEP 1.17 0.3 1.25 0.3 <br />OCT 0.9 2.8 1.01 2.7 <br />NOV 0.78 6.4 0.84 6.4 <br />DEC 0.63 7.1 0.71 7.5 <br />Annual Total 14.94 47.8 16.32 53.3 <br />Groundwater Quantity <br />Water levels in all of the alluvial wells varied seasonally showing increases in the <br />spring to early summer. Generally, these water levels were consistent with 1997 <br />through 2001 measurements. Increases noted in March and May can be attributed to <br />spring moisture and runoff events causing flows in the stream drainage (see surface <br />water discussion below). Since 2000, coal bed methane development and associated <br />• dewatering to surface streams has increased water levels in alluvial wells in those <br />drainages where discharge occurs. Monitoring results of water levels in these wells <br />are contained in Appendix I Field Notes and Appendix III Ground Water Data. <br />6