Laserfiche WebLink
Lorenciro Canyon Mine Annual Hydro[oAic ManitorinA Report - 2007 <br />Pond Sites <br />In addition to the springs, seeps, and streams, ponds are also present on [he site. These ponds <br />are utilized to provide water for livestock and wildlife. A total of nineteen ponds were located <br />by ground and aerial surveying methods (Map 2.04.7-1). A large number of these ponds (eight) <br />are located in the Cow Canyon drainage. The other ponds are scattered over the site, with <br />generally no more than two in any drainage. All ponds located appear to be artificial, with man- <br />made dams at one end. Water level in the ponds varies from season to season depending on <br />runoff received in the drainages, however, all ponds consistently hold water. No ponds were <br />monitored in 2001. <br />Surface Water Quality <br />Applicable standards for the Lorencito Canyon Mine are set forth by the Colorado Department <br />of Public Health and Environment, Water Quality Control Commission document Classifications <br />and Numeric Standards for Arkansas River Basin (3.2.0), effective August 30, 1995. Receiving <br />stream standards from Region 7, Lower Arkansas River Basin, Stream Segment Sa were utilized. <br />These standards refer to the Mainstem of the Purgatoire River and the Middle Fork of the <br />Purgatoire from the USGS gage at Stonewall to Interstate 25. Standards included physical, <br />biological, inorganic, and metals. <br />Surtace Water Stations <br />Data was collected from each of the surface water stations during the 1996 to 2001 monitoring <br />period. Each of the stations were monitored semiannually for field parameters and samples were <br />obtained in November 2001 from the site for laboratory analyses. Summary tables showing the <br />results from all the surface water locations are included in Appendix 2. Stations LC-1, LC-2, and <br />PC-1 showed signs of increased levels of TDS related to coalbed methane development. <br />Results from the surface water laboratory analyses was interpreted through the use of Piper and <br />Stiff diagrams. These diagrams indicate principal cation and anion milliequivalents per liter and <br />are useful for determining water type. Copies of these diagrams are included in Appendix 2. <br />The principal water type in the surface waters is acalcium-sodium bicarbonate type. This water <br />is typically neutral to partially alkaline, with low hardness, and low to moderate salinity. pH <br />ranges from 7.4 to 8.7, and hardness ranges from 107 mg/L to 435 mg/L. Total dissolved solids <br />in the samples ranged from 210 - 980 mg/L (filterable residue). <br />Spring and Seep Stations <br />No water quality samples were collected at springs during 2001, however, water quality sampling <br />during the baseline period revealed slightly to moderately alkaline, slightly hard, calcium-sodium <br />bicarbonate water, with total dissolved solids ranging from 300 mglL to 710 mg/L. Total <br />alkalinity in the samples ranged from 223 mg/L to 409 mg/L, and hardness ranged (as CaCO3) <br />from 214 mg/L to 388 mg/L. pH ranged from 6.70 to 9.15. A summary of the 2001 monitoring <br />results are contained in Appendix 3. <br />AHR-OOA]5\APril Z6, 30@ 7 <br />