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SECTION 3 - RESULTS AND DISCUSSION <br />• The Lorencito Canyon Mine is located on tributaries south of the Purgatoire River, 2.7 <br />miles east of Weston, Colorado. The headwaters of the Purgatoire are located eighteen <br />miles west of the permit area, and the river is draining 403.7 square miles of watershed <br />at its confluence with Lorencito Canyon. The Purgatoire is a tributary of the Arkansas <br />River. Precipitation in the 2007 calendar year was about 110% of average for the year. <br />Groundwater Quantity <br />Water levels in all of the alluvial wells varied seasonally showing increases in the spring <br />to early summer. Generally, these water levels were consistent with 1997 through 2001 <br />measurements. Increases noted in March and May can be attributed to spring moisture <br />and runoff events causing flows in the stream drainage (see surface water discussion <br />below). Since 2000, coalbed methane development and associated dewatering to surface <br />streams has increased water levels in alluvial wells in those drainages where discharge <br />occurs. Monitoring results of water levels in these wells are contained in Appendix I <br />Field Notes and Appendix III Ground Water Data. <br />• Data was collected from each of the alluvial wells (MWJC-1, MWLC-1, MWLC-2, and <br />MWPC-1) during the 1996-2000 baseline monitoring period. Alluvial wells MWLO-W <br />and MWLO-E at the loadout facility were installed during April 2002. During 2007, <br />wells MWJC-1, MWLC-1, and MWLC-2 were monitored semi-annually for water level <br />and field parameters and annual water samples were obtained for laboratory analyses. <br />Summary tables showing the results from all the alluvial wells are included in Appendix <br />III and Lab Reports in Appendix IV. <br />Results from the laboratory analyses of baseline samples were interpreted through the <br />use of Stiff diagrams. Copies of these diagrams are also included in Appendix III. The <br />principal water type observed in the alluvial wells is a calcium-sodium bicarbonate type. <br />This water is typically neutral with low hardness and low to moderate salinity The pH <br />ranges from 7.42 to 8.7 and hardness ranges from 145 mg/L to 605 mg/L. Total <br />dissolved solids in the samples ranged from 260 to 1340 mg/L (filterable residue). <br />Discharge thought to be associated with coalbed methane has increased dissolved solids <br />in streams and alluvial well waters at stations MWJC-1, MWLC- 1, MWLC-2, and <br />MWPC-1 as compared to the baseline period prior to commencing CBM activities. <br />0 6