Laserfiche WebLink
Lorencito Canyon Mine Annual Hydrologic Monitoring Report - 2001 <br />sample of the water with a decontaminated beaker, and placing the probes in this sample for <br />measurement. Samples were obtained from flowing water where possible. Decontamination of <br />all equipment was performed by first rinsing the equipment with tap water, then washing with a <br />phosphate-free detergent, then rinsing the equipment with deionized water. <br />Samples were obtained using the laboratory provided sampling containers, where possible. Each <br />container was lowered into the water and filled gently, without rinsing out the preservative. For <br />samples requiring field filtration, filtration was accomplished by use of a barrel filter with a 0.45 <br />micron filter. <br />Statistical Data Reduction Methodology <br />The analytical results and field parameters were plotted to determine water types. Mean, <br />median, and standard deviation values were generated to determine the accuracy and precision of <br />the data. Major cations and anions were plotted on trilinear (Piper, 1944) and Stiff diagrams for <br />comparative analyses of water types. <br />SECTION 3 -RESULTS AND DISCUSSION <br />' The Lorencito Canyon Mine is located on tributaries south of the Purgatoire River, 2.7 miles <br />east of Weston, Colorado. The headwaters of the Purgatoire are located eighteen miles west of <br />the permit area, and the river is draining 403.7 square miles of watershed at its confluence <br />' with Lorencito Canyon. The Purgatoire is a tributary of the Arkansas River. Precipitation in <br />the 2002 calendar year was drier than average throughout the year. <br />' Groundwater Quantity <br />Water levels in all of the alluvial wells varied seasonally showing increases in the spring to <br />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 and <br />runoff events causing flows in the stream drainage (see surface water discussion below). Also, <br />coalbed methane development and associated dewatering to surface streams has increased <br />water levels in alluvial wells in those drainages where discharge occurs. Monitoring results of <br />water levels in these wells are contained in Appendix 1 and hydrographs of well data are also <br />contained in Appendix 1. <br />AHR-00.405\MamM1 10, 2003 <br />