2014-01-14_REPORT - C1980004 (4)

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2013 AHR McClane & Munger Canyon Mines Page 5 above and below the mine site are generally the same for all parameters. The McClane Canyon Mine discharged to East Salt Creek every month of the water year, October 2012 through September 2013. Routine quarterly wet tests were performed in each quarter. No pattern of toxicity was found. Table 6 contains analyses of mine water discharged into East Salt Creek all four quarters, with a full suite being analyzed in the first quarter of 2013. The mine water had an average TDS value of 2,380 mg /I. Due to dry conditions at the time of quarterly inspections, no samples were collected for East Salt Creek during water year 2013. But it is unlikely mine discharge had a negative impact on the quality of East Salt Creek due to the limited disturbance associated with the mines and as evidenced by documents presented in past annual hydrologic reports. Groundwater Table 5 shows the results of groundwater sampling during the water year. Table 5a was created in 2011 for GW -10 to be used to gather a year of baseline data, however, GW -10 was sealed in 2012 since a large coal mine waste pile is no longer planned and therefore GW -10 is no longer required. Baseline data for Table 5 from the 1981 & 1986 monitoring is also shown. Baseline data for GW -9 for the period October 2007 through September 2008 is included. Results of quality sampling are consistent with the results from previous years. GW -4 was in close proximity to a hay field that is irrigated during dry periods and in danger of being eroded with an oxbow has been replaced with GW -3. GW -3 is located adjacent to the road south of GW -4 and should be outside of the influence of the irrigation of the hay field. Refer to Figure 4.2 -2 of the McClane Canyon Permit. The Division of Reclamation, Mining and Safety has approved this substitution. Ground water wells GW -2, GW-4, GW -7, and GW -8 were sealed during 2007. Pond Discharges There was no discharge from the McClane or Munger sediment ponds during the water year. The sediment fences at McClane, Munger Canyon and Loma were maintained as necessary. Discharge monitoring from the sediment ponds and mines are regulated by the Colorado Discharge Permit System Numbers CO- 0038342 (McClane) and CO- 0040827 (Munger). Copies of Quarterly Discharge Monitoring Reports have been provided, under separate cover, to the DRMS at the same schedule required by the CDPS Permit. They are included in this report by reference. McClane Creek Temporary Diversion The Operator placed four wooden gabions in the McClane Creek channel during 1997 to ensure the channel would remain stable. The gabions were to provide a solid place in the channel bottom to limit any further erosion. In 2004 a re- survey