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Geologically, except for surficial deposits, only the coal hearing <br />Cretaceous Plesa Verde Group outcrops within the permit area. The <br />Expanded Columnar Section, Figure 1, shows tfie stratigraphic location of <br />the three coal seams in the area. They are in ascending order the Lower <br />Pinnacle, the Upper Pinnacle and Zone 3 seams. All three seams are part <br />of the Iles Formation which is hounded by the Trout Creek Sandstone <br />Member above and the Tow Creek Sandstone plember below, Horst and graben <br />faulting has divided the permit area into three fault blocks. The faults <br />run towards the northwest and the coal dips 10 degrees also to the <br />northwest. <br />Two categories of potential aquifers exist within the permit area: <br />alluvial deposits associated with the stream of Trout Creek and bedrock <br />groundwater stored in the Tow Creek Sandstone. Small, isolated alluvial <br />deposits line Trout Creek within the permit and adjacent areas. The <br />nearest alluvial well downstream of the mine is over a mile and a half <br />away, <br />The only regional aquifer within the permit area is the Tnw Creek <br />Sandstone which is over 600 feet below the coal seam being mined. The <br />Trout Creek Sandstone, another regional aquifer in the general area, has <br />been eroded from above the coal seams being mined. Because of the low <br />permeability of the interheddeA shales and siltstones of the Iles <br />Formation, the Tow Creek Sandstone is recharged primarily where it <br />subcrops in the stream bottoms. The nearest subcrop of the Tow Creek <br />Sandstone to the permit area is approximately one mile upstream of the <br />mine. Low vertical permeability results in the formation of parched <br />aquifers in local lenticular strata. These percheA aquifers recharge and <br />discharge within a short distance forming small seasonal springs and <br />seeps. These springs have been identified and are shown on the attacheA <br />map of Regional Geology and Cross-Section, Map 2. <br />Map 2 also shows the surface water features of the permit and adjacent <br />areas. The permit area lies on the drainage divide between MiAdle Creek <br />to the north and Trout Creek to the south, both of which are trihutary to <br />the Yampa River. All runoff from tfie 5.6 acres of disturbed surface is <br />diverted to the sedimentation pond which eventually discharges to Trout <br />Creek. <br />The surface facilities area was disturhed prior to the enactment of the <br />Colorado Surface Coal Mining Reclamation Act. Since quantitative <br />vegetation data was not required when the surface disturbance occurred at <br />the Apex Mine, no premining soils or vegetation data is available, <br />Therefore, the operator provided SCS soils mapping and range site <br />descriptions based on adjacent areas with similar topography, aspect anA <br />parent material. <br />Extensive wildlife haseline studies which cover the Apex No. 2 Mine <br />permit area have been conducted by the Colorado Division of Wildlife and <br />Colorado-Yampa Coal Company, a nearby surface coal mine. No rare or <br />endangered species were identified within this permit area. <br />-5- <br />