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Monitoring Frequency — Ground Water <br />Four ground water wells are monitored at the site on a semi - annual basis for both water level and water <br />quality. Two wells (MW -16 and MW -65) are completed in the Jack 0 'Lantern coal seam and two <br />wells (MW -23 and MW -NW) are completed in the Red Arrow coal seam. These four wells were <br />visited in June and December of 2010. MW -NW and MW -16 were each found dry on both visits. <br />MW -65 and MW -23 returned normal water levels, as compared to historic data, and samples were <br />taken from both wells during both the June and December visits. These samples were tested for the <br />constituents suggested in Exhibit 25, part III (C)(5.) <br />Water Quantity and Quality <br />Review of the 2010 data and the historic data for surface and ground water indicates no evidence of <br />any significant or unpredicted impact to water quantity in the surface and ground water systems. Some <br />decline in water level in the ground water system is evident in past data, likely due to underground <br />mining and subsidence. A slight recovery is noted in MW -23 but more sampling will be needed to <br />determine if this is a trend. Impacts are likely transient and temporary and are locally of no <br />consequence due to the lack of use in the general area. At this time, well MW -NW remains dry and is <br />not recording the flooding of the workings. It could be concluded that the water has yet to reach the <br />elevation of the screened interval of this well. Continued monitoring is necessary to validate the <br />prediction that mine flooding will eventually result in recovery of the local ground water level. Water <br />levels for 2010 indicate no changes due to past mining activities. <br />Water quality sampling data indicate no significant changes in water quality of the surface and ground <br />water in the mine permit area. Field data regarding conductivity and pH indicate no change in general <br />surface water quality. However, some elevated levels must be scrutinized in the future for <br />continuing trends: Calcium and Magnesium in MW -23 and Nitrogen (Nitrate plus Nitrite) in <br />MW -65. <br />Inflow to the workings acts as a pumping well; therefore, ground water flow is from the perched <br />aquifers surrounding the mined area toward the mine workings. Until water is measured in MW -NW <br />(completed in the mine workings), no conclusion regarding ground water quality can be made. <br />Continued monitoring in accordance with the approved plan may provide more definitive information <br />in the future. <br />The mine is in compliance with the hydrologic monitoring requirements and with the predictions made <br />in the permit application regarding impacts to the hydrologic regime, to the extent that the current data <br />can be interpreted. <br />Sincerely, <br />Robert Zuber, P.E. <br />Environmental Protection Specialist <br />