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West Elk Mine 2013 Annual Hydrology Report 51 No significant mining induced impacts to water quality or flows in the NFGR are anticipated in WY 2014, because mine discharges are not expected to increase significantly and the discharge water quality is expected to remain the same. Table 13. Summary of Salinity Loading in the North Fork of the Gunnison River (1) Using WY 2013 CDPS DMR TDS concentrations and flow measurements provided by MCC (MCC, 2014) (Z) Based on maximum permitted discharge rate 5.2 Springs and Seeps MCC currently monitors 40 springs and seeps (Table 5). Hydrographs of the spring and seep flows are presented in Appendix D and the spring flow and water quality data are presented in Appendix E. 5.2.1 Impacts to Spring and Seep Water Quality Spring water quality data are collected for permit - specified parameters at monitored springs and seeps throughout the permit area, in order to detect potential impacts of mining activities. Typically, underground coal mining does not impact spring water quality, but it can reduce or eliminate flows due to subsidence or dewatering. Water quality data from WY 2013 do not indicate significant changes from baseline conditions for most of the monitored springs. However, many of the springs had slightly elevated TDS /TSS, iron, and /or conductivity values that were also noted in WYs 2004- 2012. These elevated values are likely the result of seasonal variations and are not related to mining operations. Potential mining impacts to area spring and seep water quality are determined by comparing current water quality data to maximum baseline values and climatological conditions such as drought or high precipitation periods at monitored sites hydraulically connected to areas with mining activities. Field pH values were used for comparison when they were available, as the holding time for the lab pH is typically exceeded due to the shipping time required for samples to reach the analytical lab. The discussion below includes monitoring locations where one or more parameters had values 10 percent or higher than comparable maximum baseline values. Spring water quality parameters that are above 10 percent of the baseline maximum are typically the result of natural variations in climate or flow conditions the day the sample was collected. It should also be noted that baseline values are based on limited data and only give a general indication of seasonal variability. Baseline water quality data for springs 2012 -1, 2012 -2, 2012 -3 and 2012 -4 was collected from May through October 2013. The following springs did not have any parameters June 2014 HydroGeo, Inc. Average Maximum Flow Calculated Continuous Weighted TDS Annual Percent of Scenario Discharge Rate Concentration Salinity CHIA (gpm) gym) Loading Loading tons/ ear WY 201311 1.98 <1 0.91 0.003 2003 CHIA �Z� 5,520 2,500 30,159 - - (1) Using WY 2013 CDPS DMR TDS concentrations and flow measurements provided by MCC (MCC, 2014) (Z) Based on maximum permitted discharge rate 5.2 Springs and Seeps MCC currently monitors 40 springs and seeps (Table 5). Hydrographs of the spring and seep flows are presented in Appendix D and the spring flow and water quality data are presented in Appendix E. 5.2.1 Impacts to Spring and Seep Water Quality Spring water quality data are collected for permit - specified parameters at monitored springs and seeps throughout the permit area, in order to detect potential impacts of mining activities. Typically, underground coal mining does not impact spring water quality, but it can reduce or eliminate flows due to subsidence or dewatering. Water quality data from WY 2013 do not indicate significant changes from baseline conditions for most of the monitored springs. However, many of the springs had slightly elevated TDS /TSS, iron, and /or conductivity values that were also noted in WYs 2004- 2012. These elevated values are likely the result of seasonal variations and are not related to mining operations. Potential mining impacts to area spring and seep water quality are determined by comparing current water quality data to maximum baseline values and climatological conditions such as drought or high precipitation periods at monitored sites hydraulically connected to areas with mining activities. Field pH values were used for comparison when they were available, as the holding time for the lab pH is typically exceeded due to the shipping time required for samples to reach the analytical lab. The discussion below includes monitoring locations where one or more parameters had values 10 percent or higher than comparable maximum baseline values. Spring water quality parameters that are above 10 percent of the baseline maximum are typically the result of natural variations in climate or flow conditions the day the sample was collected. It should also be noted that baseline values are based on limited data and only give a general indication of seasonal variability. Baseline water quality data for springs 2012 -1, 2012 -2, 2012 -3 and 2012 -4 was collected from May through October 2013. The following springs did not have any parameters June 2014 HydroGeo, Inc.