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3.0 <br />There is potential for dewatering of groundwater aquifers located within and above the Maxwell coal seam <br />member of the Raton Formation. Previous studies included in the mine permit document project inflow of as <br />much as 180 gpm and indicate an azea of influence on groundwater up to 2.1 miles from the perimeter of the <br />mine workings. The average discharge when discharge occurred from the mine at Pond 002 was 76 gpm. The <br />maximum discharge from Pond 002 was 148 gpm. The workings are now flooding, which is resulting in <br />changes in the potentiometric surface around the mine in the future. <br />Localized dewatering was evident from the flow of groundwater (seeps, etc.) into the underground mine <br />workings, and the pumping and discharge of these mine waters into surface flows. However, no loss of springs <br />or impacts to existing adjudicated wells have been noticed to date. Relatively constant flows suggest a general <br />low quantity of water within the formations, and retention of member integrity with retention of low vertical <br />transmissivity of free water. Future monitoring will be used to further identify effects of dewatering. <br />There has been no noticeable impact on groundwater hydrology from the gradual flooding ofthe Golden Eagle <br />Mine. The apparent low vertical transmissivity and integrity of the surrounding rocks might inhibit any effect <br />of free water on the recharge of the overburden. Monitoring of the underground workings began in 1997 at <br />GEM-1, GEM-2, and GEM-3. Rate of filling of the workings will be monitored through time and any effects <br />will be identified. GEM-1 showed a slight rise in water level in 2002. GEM-2 had water for the first time in <br />the fourth quarter of 2000 and the level rose approximately I S feet in 2002. GEM-3 had water for the first <br />time in first quarter of 2001 and the level rase approximately 15 feet in 2002. GEM-1 is the highest elevation <br />of the mine floor of the three GEM wells. Water measured at this site is probably spilling to the north into the <br />extensive area of longwall mining north of Highway 12. <br />3.2 WATER QUALITY <br />3.2.1 Springs and Seeps <br />The 2002 spring and seep survey occurred during August 22 to September 6, 2002. Flows were consistent <br />with those previously measured; however, drought conditions during the past year eliminated flow at many of <br />the monitoring sites. There is no evidence that mining activities have affected the water quality of springs or <br />seeps, nor are such changes anticipated. <br />3.2.2 Surface Water (Streams, Ponds and Direct Discharges) <br />All surface water monitoring points have been eliminated from the monitoring program. <br />3.2.3 Alluvial Groundwater <br />PAW-6 documents an additional loading of dissolved solids greater than that observed at PAW-5, in that it <br />detects mine water discharges. Solids levels in the PAW-6 sample taken in 2002 show decreases from <br />previous years which indicates that effects of mine water discharge are diminishing. Figure 3.2-1 shows water <br />quality at the two PAW stations. However, the historic records of PRS-3 indicates little effect on stream <br />quality from the local sources of alluvial groundwater. Well CCAW-1 is located down gradient of the <br />development waste storage area and shows elevated levels of dissolved solids (Figure 3.2-1). <br />292-2002 AH Report (Mar.03.03)_rev2 1 1 <br />