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from 2003 through the present. Finally, MW -65 had an initial steady water level rise, then decline, between <br />1983 and 1988; water levels have remained within 10 feet of historic data from 1988 through the present. <br />Localized alteration of groundwater flow patterns are probably occurring, as explained by Boulay, due to <br />the groundwater preferentially passing through the abandoned mine workings. Similar changes in <br />groundwater flow patterns have been occurring in the Southfield Mine area since the establishment of other <br />underground mining operations beginning in the early 1900's. <br />EFCI concurs that there were possible increases in recharge as a result of mine dewatering while the <br />mine was in operation. Mine inflows were significantly less than the predicted 330 acre feet per year, and <br />consequently dewatering flows were insignificant compared to the potential flow rates through the mined <br />strata within the groundwater basin. <br />EFCI reviewed groundwater quality data, presented in the Annual Hydrology Reports, to evaluate <br />potential increases in the levels of TDS and concentrations of specific chemical constituents. As stated by <br />Boulay, indicator parameters including TDS, manganese, and iron were selected for comparison because <br />they are important parameters and they are required by Rule 2.04.7 for baseline characterization. EFCI <br />agrees with Boulay's conclusion that monitoring data do not show any significant trends between the <br />baseline information and recent samples. Likewise there is no discernible trend between up- gradient and <br />down - gradient monitoring points. Boulay goes on in his findings to say that all three wells for which <br />baseline data was collected showed exceedances of the iron and manganese standards in the baseline <br />samples (Regulation No. 41 The Basic Standards for Ground Water). Samples from MW -23 and MW -65 <br />exceeded the manganese standard in more recent samples from these wells on several occasions. However, <br />the manganese exceedances in these wells is on the same order of magnitude as the baseline samples so no <br />discernible trend is identifiable. As stated in the Permit, groundwater within the mine area has a neutral pH <br />and relatively high levels of sodium, sulfate, and iron. Based on analysis results there does not appear to be <br />any significant decrease in coal seam groundwater quality resulting from the Southfield Mining operation <br />as compared to coal seam groundwater quality prior to the Southfield Mine operations. <br />Surface Water Consequences <br />1. Temporary increases in runoff for surface disturbance areas <br />2. Minor reductions in surface flows due to operation of sedimentation structures <br />3. Alteration of surface flow patterns <br />4. Changes in surface water chemistry — Increases in levels of TDS and specific chemical constituents <br />Probable surface water consequences appear to be consistent with the findings made by Boulay and the <br />DRMS (refer to above referenced Memorandum), and are supported by the surface water data provided in <br />the Annual Hydrology Reports and included in the Historical Water Data sheets in Attachment C. <br />Surface disturbance areas likely created increases in runoff while the mine was in operation. Surface <br />runoff has significantly decreased following reclamation and revegetation establishment on disturbed areas <br />based on pond discharge records shown in the Annual Hydrology Reports. <br />Minor reductions in (off site) surface flows have occurred due to operation of sedimentation structures. <br />One sediment pond, Pond 1, was removed during reclamation of the mine site. The volume of water retained <br />in the two remaining sediment ponds, Pond 4 and Pond 5, from storm runoff constitutes a relatively small <br />portion of the total runoff from the Newlin Creek watershed. <br />3 <br />TR -43 Revised: 10/2014 <br />