2015-08-11_GENERAL DOCUMENTS - C1992080

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1600 and 1800 feet of light to dark gray and black shales that contain interbeds of light brown sandstone, sandy to silty limestones, calcareous concretions, and bentonite. This formation is erosive and wide valleys have formed within this unit to the north. The Pictured Cliffs Sandstone conformably overlies the Lewis Shale, is 200 feet thick, and consists of two members. The lower member consists of 80 feet of interbedded shales and sandstones. The Upper Pictured Cliffs Sandstone consists of 120 feet of massive sandstone with some thin interbeds of shale and siltstone. The sandstone is white to light gray, well sorted (uniform grain size), fine to medium grained, and contains silica and calcareous cement. This sandstone is resistant to erosion and forms prominent ridges, cliffs, and steep sided stream valleys (water gaps) in the area. (Fassett and Hind, 1971 and Shomaker, et. al., 1971.) The Upper Pictured Cliffs Sandstone locally intertongues with the overlying Fruitland Formation. The Fruitland Formation is coal -bearing. The Lewis or "C" coal seam is in the Fruitland Formation. The Lewis coal seam is the lowest coal seam that was to be mined. The Fruitland Formation is the coal bearing formation in the permit and adjacent areas. This formation is composed of laterally discontinuous interbedded and lenticular sandstones, siltstones, shales and coals. The formation is a terrestrial deltaic deposit and is gray to brown and black with greenish shale and gray - green fine grained dense feldspathic sandstones in the upper parts. The Fruitland Formation contains three minable coal seams. In ascending stratigraphic order, the seams are the Lewis or "C" seam, the Carbonero or "B" seam, and the Shamrock or "A" seam. The Lewis seam is approximately 17 feet thick and consists of high volatile C bituminous coal. The Carbonero or "B" seam is approximately 28 feet thick, contains a five-foot parting of shale and bone, lies 105 feet above the Lewis seam, and is a high volatile C bituminous coal. The Shamrock or " A" seam is located about 87 feet above the Carbonero seam, is about 21 feet thick, and is classified as a high volatile C bituminous coal. The Shamrock seam is overlain by 0 to 120 feet of overburden strata in the permit area. The entire overburden section is in the Fruitland Formation. The Kirtland Shale conformably overlies the Fruitland Formation. This shale is divided into three main members: the upper and lower shales and the middle Farmington Sandstone. The Farmington Sandstone member forms a permanent ridge separating Carbon Junction Canyon and REA Canyon. The lower shale member consists of gray to gray -green shale and sandy shales. The upper shale member consists of interbedded shales and sandstones. The Quaternary terrace deposits consist of Pleistocene -aged gravels related to glaciation in the area. Three gravel terrace layers have been mapped in the area and represent previous flood plains of the Animas River. These deposits vary between I and 100 feet thick and consist of boulders and cobbles in a silt clay matrix. Quaternary alluvial deposits are primarily located along the Animas River. Thin (less than three feet thick) isolated alluvial bodies are located in Carbon Junction Canyon. The Quaternary terrace deposits are at best limited aquifers. These deposits have a coarse gravel -boulder layer at their base that tends to drain the deposits to the side slopes of the Animas River Valley. The terrace deposits do not supply subirrigation to crops. These terrace deposits are currently used regionally for dry land wheat farming. The alluvium of the Animas River is a regional aquifer located 400 feet below the main mining operation. The alluvium is poorly sorted and coarse-grained, with ground water levels coincident with the river level. The alluvial body thins and becomes narrow at the point where the Animas River cuts through the