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There are five bedrock wells and three piezometers which will be used to evaluate water • <br />bearing zones and monitor the effects of dewatering and subsidence. One well in the coal <br />seam (NM-21) will evaluate the Maxwell seam. Three piezometers into the mine <br />workings (GEM-1, GEM-2, and GEM-3) will provide direct information on the flooding <br />of the workings and its recharge. Four wells in the overburden (LA-264, SF-2, NM-22 <br />and NM-20) will evaluate water bearing zones above the coal which could conceivably <br />be utilized for beneficial use and which might be impacted by mining. Well LA-264 was <br />tested in the Fourth Quarter of 2001 at which time a blockage was discovered in a zone <br />approximately 65 feet below ground level. The Division was informed of the defect in <br />the well and the decision was made to abandon the well in December of 2001. <br />Monitoring wells NM-20, NM-21, NM-22, and SF-2 were established in 1994 to provide <br />ground water monitoring in areas to be approached by anticipated future mining of the <br />Maxwell seam to the north of, and southeast of, the permitted mine plan. With the mine <br />closure in 1995, these plans were never implemented. Approval was received from the <br />Division to reduce monitoring of these locations to annual monitoring of water levels in <br />Mid-2003. <br />Point of Compliance <br />Ground water monitoring data for Total Dissolved Solids (TDS) from Alluvial <br />Monitoring Wells PAW 5 and PAW 6 show no deterioration in water quality (TDS) from <br />the baseline year 1994 through 2000 (five years after cessation of mining). V/elI NM-21 • <br />was installed in 1995 to provide baseline data for the Maxwell (Golden Eagle) Coal <br />Seam. Gem-1 monitors water quality of mine-water inflow into the Golden Eagle Mine. <br />Table 26 compares data for PAW 5 and PAW 6 and NM-21 with current data for the <br />Golden Eagle Mine water. <br />TABLE 26 TOTAL DISSOLVED SOLIDS (mg/I) <br /> Annual Maximum Value <br />Monitoring Well Baseline 2000 Percent Change <br />PAW 5 (1994) 390 320 -22% <br />PAW 6 (1994) 330 330 0% <br />NM-21 (1995) 1400 <br />GEM-1 1380 -0. I <br />Based on analysis of present TDS levels as compared to baseline data, there has been no <br />negative (increase in TDS>1.25) impacts on water quality. The determination therefore is <br />that there is no requirement for point of compliance monitoring <br />TR-54 2.05-47-f' (Revision 6/03) <br />• <br />