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Of the two mineable coal seams exposed in the permit area, only the upper seam (Peacock, or <br />"A ") of the Menefee formation was developed at the King I Mine and is currently being <br />developed at the King II Mine. Thickness of the upper seam ranges from less than 48 inches to <br />more than 76 inches. The upper seam lies approximately 22 feet below the base of the Cliff <br />House sandstone, and has 100 to 400 feet of overburden throughout much of the permit area. <br />The lower ( "B ") coal seam is well exposed at the Burnwell Mine. This operation, located <br />adjacent to the King I Mine, began in the 1940s, but has long been abandoned and was never <br />permitted under SMCRA. The lower coal seam of the Menefee Formation has an average <br />thickness of 48 inches. This seam lies approximately 80 feet below the upper seam, with inter- <br />bedded sandstone and shale between the two seams. To the north of the permit area, the <br />interburden between the "A" and "B" seams may thin out, resulting in a single, thicker "A" <br />seam. <br />Ground Water Hydrology (2.04.5 and 2.04.7) <br />The following four water - bearing stratigraphic units have been identified in the vicinity of the <br />permit area: the alluvium of Hay Gulch (unconsolidated stream gravel, sand, silt, and clay of <br />Recent age), the Cliffhouse Sandstone (Cretaceous marine barrier bar complex), the Menefee <br />Formation (Cretaceous fluvial sandstone and coal deposits), and the Point Lookout Sandstone <br />(Cretaceous marine beach and bar deposits). <br />The Hay Gulch alluvium consists of unconsolidated and poorly consolidated gravel, sand, silt, <br />and clay that was deposited by stream flow in Hay Gulch during the last several thousand years. <br />The alluvium is several tens of feet thick and approximately 1,000 feet wide. GCC has monitored <br />the Hay Gulch alluvium for more than 20 years in a monitoring well (the Wiltse well) next to the <br />King I Mine. Ground water in the alluvium is unconfined. The alluvium is recharged by <br />snowmelt and precipitation, and by seepage from the Menefee Formation subcrop along the <br />north side of Hay Gulch. The elevation of the water table varies seasonally, ranging from just <br />above the ground surface to a few feet below the surface. Ground water in the alluvium probably <br />flows downstream along Hay Gulch. GCC's annual hydrology reports show ground water in the <br />Hay Gulch alluvium is a magnesium - calcium - sulfate type of water that has a high concentration <br />of total dissolved solids (TDS). TDS concentrations consistently are more than 1,500 mg /1, <br />rendering the water unsuitable for domestic and irrigation purposes, but marginally suitable for <br />stock watering. Sulfate concentrations are greater than 600 mg/l. Sulfate concentrations greater <br />than 250 mg/l can cause weight -loss in livestock. There are no known private wells completed <br />in the Hay Gulch alluvium near the permit area, other than a well used by the King I Mine. <br />The Cliffhouse Sandstone is a fine- grained sandstone that was deposited in a barrier bar complex <br />along a marine shoreline. The Cliffhouse is more than 200 feet thick. NKC's mine workings <br />directly underlie the Cliffhouse in the Menefee Formation. Water supply wells that are located <br />within one mile of the permit area and are probably completed in the Cliffhouse Sandstone <br />include the G. Paulek and L. Paulek wells located in Section 11 and drilled in 1969 and 1979, <br />respectively. A domestic well located in the SE corner of Section 6 (the Shafer well), completed <br />in 1977, may also tap the Cliffhouse unit. This well is located within the southern portion of the <br />permit boundary, and was not under - mined. <br />0 <br />