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Completion ofevaluation required by Section 3.03.2(2). The Division has conducted an evaluation <br />of the reclamation work, in accordance with Section 3.03.2(2). This evaluation considered, among <br />other things, the results of inspections and monitoring, the need for further reclamation work, and <br />whether pollution of surface or subsurface water is occurring, and the probability of future <br />occurrence of such pollution. The results of the evaluation of hydrologic impacts are summarized <br />below. The evaluation concluded that all reclamation has been completed in the bond release area, <br />no water pollution is occumng, and there is no potential for future water pollution. Impacts to <br />ground water and surface water aze described below. <br />Ground Water Impacts: <br />The Division conducted a detailed analysis of potential ground water impacts at the Edna <br />Mine in a review of the 2002 annual hydrology report. The results of the analysis aze <br />described in a memo to the annual hydrology report file dated October 10, 2003. <br />Mining and reclamation operations in the bond release azea are unlikely to have caused <br />adverse impacts to water in bedrock aquifers for the following two reasons: 1) there was <br />no significant disturbance of bedrock in the bond release area (the coal strip pits were <br />down-dip from the bond release azea), and 2) the bond release azea is not within a <br />significant rechazge zone of bedrock aquifers. Operations in the bond release azea did not <br />generate significant amounts of leachates or contaminated dischazges, therefore, direct <br />contamination of both bedrock and alluvial aquifers was unlikely. All of these conditions <br />(geologic setting, lack of contaminants, etc.) indicate the permittee minimized hydrologic <br />impacts within the bond release azea, and has prevented material damage to ground water <br />outside the permit area, down-gradient from the bond release area. Also, aquifer rechazge <br />has not been diminished (infiltration of meteoric waters into the ground surface has not <br />been reduced), and the permittee has not caused adverse impacts to ground water that <br />impair the postmining land use. The improbability of adverse impacts to ground water <br />indicates the operation is in compliance with the Basic Standazds for Ground Water <br />(Colorado Water Quality Control Regulation 41.S.C.6). <br />Surface Water Impacts: <br />The only surface water features in the bond release azea are the perennial stream, Oak Creek, <br />and ephemeral drainages that extend down the east facing hillslope of the bond release area. <br />These ephemeral drainages drain to Oak Creek. The ephemeral drainages have not been <br />disturbed by P & M's operations. Ditches route runoff from the conveyor corridor and the <br />Goat Trail roadway to the Tipple ponds a short distance north of the bond release azea. P & <br />M has conducted long-term monitoring at a flume at the outlet of the Tipple Pond farthest <br />downstream (CDPS outfall 001). The ponds hold water only a few weeks each year <br />following springtime snow melt and large rain storms. There have been no exceedances of <br />dischazge limitations at outfall 001 for at least 5 yeazs. These dischazge limitations were <br />based on which chemical constituents were likely to be present in discharge effluent, and did <br />not include all of the constituents for which there are instream standazds in Oak Creek. It is <br />unlikely, however, that the influent would have contained these other constituents in <br />10 <br />