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Based on the foregoing analysis, the Division makes the finding that the Seneca II Mine site has been designed to minimize off-site surface water impacts. Ground Water Both consolidated and unconsolidated aquifer systems have been identified at and near the Seneca II Mine site. These aquifers may be affected by surface coal mining operations at this site. The Trout Creek Sandstone stratigraphicallyundeAies the Wolf Creek Coal by 70 feet. The intervening strata between the Wolf Creek Coal and [he Trout Creek Sandstone, which consists of lenticulaz sandstone lenses, shale and siltstone, has been identified as a confining layer in this area. This confining layer, which will not be actively disturbed by mining, will mitigate mining related impacts to the Trout Creek Sandstone. There will be no depletion or degradation of the water in this regional aquifer. The Twentymile Sandstone may be slightly impacted by the mining operation. The Bond Creek and Cow Camp Creek drainages intersect the dipping sandstone outcrop adjacent to the southeastern portion of the permit area. The alluviaUcolluvial material within each drainage will transmit water discharged from spoils aquifers upgradient in each drainage. This water, which is high in TDS, may recharge the Twentymile Sandstone at the point where the alluvial/colluvial material bisects the outcrop. The potential for water quality degradation due to potential recharge by the poor quality alluviaUcolluvial water, is the only identified potential impact to this regionally significant aquifer. The Wolf Creek Coal stratigraphically the lowest seam to be mined, along with its associated overburden, is capable of storing and transmitting small amounts of water, and in the permit area, may not meet the definition of an aquifer. Reported yields from wells completed in the Wolf Creek Coal are generally less than one gallon per minute (GPM). Furthermore, high pre-mining concentrations of iron, manganese and sulfate generally preclude use of this water for domestic or livestock use. The Seneca II Mine operation is removing the Wolf Creek Coal and overburden in the north central portion of the active mine azea, located within the regional Sand Wash Basin. One consequence of mining will be the physical removal of this unit, thus interrupting recharge to the coal and overburden aquifer. As the Wolf Creek mining area is reclaimed, the backfilled mining pits will gradually resaturate. Spoil aquifers will develop and discharge to the surface 30