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At the time of the initial permanent regulatory permit approval during the first quarter of 1982, no water was discharged from the mine workings. However, subsequent to the extension of the east mains to the east fault and north mains down dip to the northeast in a pazallel line with the east fault, mine inflows increased gradually and required periodic discharge in accordance with an approved NPDES dischazge permit (002). Mine inflows peaked at a rate of approximately 5.4 gpm shortly after the mine was idled in 1983, and steadily decreased until operations resumed in 1988. When mining resumed, additional azea in the satwated portion of the graben was opened, and inflow increased to approximately 3.9 gpm in 1990. In April, 1990, the mine section from which inflow had originated was sealed, and in July, 1992, all areas to the north of the East Mains were sealed and aze now inaccessible. No water has been produced in other areas of the mine since the section which had originally produced water was sealed in 1990. Further dewatering of the mine from areas which previously produced water is not projected to be necessary until water in the originally sealed area backs up to the seals, and is drained to a dewatering sump to be used in the mining process. At the 1990 inflow rate, this would not occur for approximately 60 years. The source of inflows to date is believed to be a mix of water infiltrating the graben along the faults and water in the coal seam. The mine has been idle since 1992, and is currently in temporary cessation. Additional mine inflows would be anticipated in the future, assuming mine operations resume, as the workings extend further to the east into the predicted saturated portion of the Cameo seam. The quantity of inflows which have been observed to date and are projected upon resumption of mining in future permit terms are considered to be insignificant with respect to effects on flow in the ephemeral surface drainages, or with respect to rechazge of the coal seam. Based on information provided in the permit application, ground water intercepted by the mine does not appear to be in communication with any aquifers being put to beneficial use, and there are no registered wells within two miles of the permit boundary. The quality of water discharged from the mine in the past was similar or higher quality than water in East Salt Creek at the confluence with McClane Creek, and any discharge is required to meet NPDES discharge standards. For these reasons, no detrimental impact to Bound water resources or to surface water quality downstream of the permit area is expected. Original ground water flow patterns in the mined area will ultimately be reestablished after the mine is sealed and the abandoned workings slowly fill with water. An alluvial aquifer has been identified along East Salt Creek. Monitoring wells established in the alluvium indicate that alluvial water levels fluctuate seasonally in response to flow in East Salt Creek. Data collected by the applicant from the Salt Creek alluvial aquifer indicate acarbonate-sulfate type water, similar to the characteristics of the surface water in the system as would be expected. No effects to alluvial ground water quality or quantity are anticipated. 20