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The uppermost portal seeps aze occurring along areas that aze overlain by burned coal zones. Due to the good quality characteristics of the water, it is assumed that this seep is occurring due to contact of the burn zone with water that is tributary to the Grass Valley Reservoir and/or Harvey Gap Drainage. This portal seep has been measured at 2 gpm. This yield is equivalent to .0045 cfs or 3.23 acre- feeUyeaz. This quantity compazed to the 5800 acre-feet storage capacity of the Grass Valley Reservoir is insignificant. During active mining, the operation plan called for this water to be consumptively used by the applicant for dust suppres- sion, and replacement of water or an augmentation plan was required. Because water is no longer being consumptively used, that requirement is no longer applicable. In summary, the level of salinity in the Harvey Gap surface water system is not predicted to rise significantly during the critical irrigation season. The level of TDS could rise in a worst-case scenario during the non-imgation season. The alluvium directly recharged by the Harvey Gap surface water system could experience a rise in TDS levels. However, due to the already high level of TDS in the alluvium, this rise is not projected to diminish the agricultural use of the alluvial water. The potential for diminution or degradation of ground water in the bedrock aquifers overlying the mined coal seam is small. This is due to: (1) the small size of the mine, (2) the lack of communication of the coal seam with overlying beds due to interbedded shale layers, and (3) the lack of potential of the rock strata within the affected section to supply a high quality ground water resource. However, although the water quality in the overlying bedrock aquifers is poor, those aquifers are used for domestic supply in the vicinity of the mine. Addifionally, mining-related subsidence has the potential to create fractures in the interbedded shale layers between the mined coal seam and the aquifers. Although the existing domestic wells lie outside the angle of draw for the mine, subsidence- related fractures could create communication between the aquifers and the coal seam, thereby disrupting the recharge zones for these aquifers, which could result in the diminution of water supply of current users. Reference: McWhorter, D.B., 1980, Procedures for Predictive Analysis of Selected Hydrologic Impacts of Surface Mining, Office of Research and Development USEPA, Cincinnati, Ohio. IV. Sealing of Drilled Holes and Underground Openings The Division will require that each hole, well, or other underground opening be capped, sealed, backfilled, or otherwise properly managed (4.07.3). 14