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Groundwater Quality <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 2003, each <br />of the wells was monitored quarterly for water level and field parameters and water <br />samples were obtained semiannually for laboratory analyses. Summary tables showing <br />the results from all the alluvial wells are included in Appendix 1. <br />Results from the laboratory analyses of baseline samples were interpreted through the use <br />of trilineaz and Stiff diagrams. Copies of these diagrams are also included in Appendix 1. <br />The principal water type observed in the alluvial wells is acalcium-sodium bicarbonate <br />type. This water is typically neutral with low hardness, and low to moderate salinity .The <br />pH ranges from 7.42 to 8.7 and hardness ranges from 208 mg/L to 605 mg/L. Total <br />dissolved solids in the samples ranged from 440 to 1310 mg/L (filterable residue). <br />Discharge associated with coalbed methane has increased dissolved solids in streams and <br />alluvial well waters. Stations MWJC-1, MWLC- I, MWLC-2, and MWPC-1 show <br />changes from the other samples taken during the period of record. <br />Surface Water Quantity <br />Watersheds in the area display dendritic drainage patterns characteristic of flow through <br />relatively flat-lying, generally uniform geologic features (Leet, et al., 1982). Eleven <br />drainage basins are within the permit boundary or received drainage from within the <br />permit boundary. All of these drainages are included in the Purgatoire River drainage. <br />The watersheds contain both forested and open slopes. <br />Surface Water Stations <br />Flow data was collected from each of the monitoring stations (Map 2.04.7-1) quarterly <br />during 2003 (Appendix 2). Flows were determined from direct measurements of the <br />water in the stream. Analyses of flow data was performed from hydrographs generated <br />from the flows. Copies of these hydrographs are also included in Appendix 2. Analyses <br />of the hydrographs from the Lorencito Stations indicate a similarity of flow. During the <br />first quarter, January through Mazch, flows were low or non-existent at some stations. <br />During the higher precipitation second quarter, flows were higher especially during May <br />when runoff was high. Flows at the side canyon stations were extremely low with some <br />stations exhibiting no flow conditions over several months. <br />• <br />6 <br />