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mny transmit only small quan[ities of water, secondary porosity may result in signifrcan[ quantifies ojgroundwater/mine inflow water migrating downgradient away from the mine workings. One concern is [hat this water would likely contain high levels of total dissolved solids (TDS) and may discharge as seeps and springs particarlarly along the coal outcrop north of [he mine workings along Hubbard Creek. The existing monitoring program does not adequately quantify impacts due to the potential for mine discharge via the coal bearing strata and/or surrounding stra[a, and no monitoring has been provided in the "D"seam down gradient ojthe mine workings to verify these conclusions or assess potential impacts. DH-l3 (completed in the upper portion of the "D "seam) is located immediately downgradient of [he proposed panel locations. However, no monitoring has ever been provided for this well since, apparently, the well had filled up with mud The well has only recently been reestablished as a monitoring well. The operator will need ro provide information to demonstrate that potential discharge of water via the mine workings will not adversely impact the Hubbard Creek drainage and/or the North Fork of the Gunnison River. Please provide an explanation of what rmpacts would occur if groundwater/mine inflow water is transmitted offsite via the abandoned mine workings and/or "D "seam. These potential impacts should be discussed in the Probable Hydrologic Consequences (PHC) portion ojthe permit. 23. An Upper Perched Water Zone is discussed on page 2.04-2~ of the revised permit text and Map 10 shows a potentiometric surface for this water bearing zone. Information presented in the TR-07 submittal indicates that the Upper Perched Water Zone may be dewatered due to mining operations, and that this perched water zone may be a major source for water flowing into the mine workings below. Based on a predicted mine discharge rate of 175 gallons per minute, this inflow may be substantial. To assess changes in the hydrologic balance and to establish baseline information on inflows, mine inflow monitoring and reporting should be incorporated into the approved water quality monitoring program. It is recommended that for flows of s:tff cient discernable volume (>Sgpm), an initial sample be obtained for laboratory anafyses and then sampled annually thereafter. The parameter list should be the same for the groundwater list currently used. Field parameters (pH, conductivity, and temperature) and inflow rates should be measured quarterly and reported in [he AHR. As indicated on page 2.O.i-67, in addition to water moving from formations above the coal seam, some water may occasionally seep into the mine from the coal seam and surrounding strata. Thus, the mine inflow monitoring should include all significant sources of inflow. 24. The PHC and the Hydrologic Reclamation Plan presented with the revised lest do not 7