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Flows from the springs and seeps were estimated during the site visit. <br />Most of the flows were observed to be less than one or two gpm. The <br />highest spring discharge was estimated to be five gpm. All of the water <br />flow in, or adjacent to, the mine permit area at the time of the study <br />was observed in Goodspring, Taylor, and Wilson Creeks. The springs and <br />seeps occurred at random elevations on the mine permit property and their <br />discharge was consumed by evapotranspiration on the valley sides and on <br />the mine face floor. There was no discharge from the seeps and springs <br />to a natural body of water such as Goodspring or Taylor Creeks. <br />During the investigation for the LRCWE report, the cut made by the <br />Colowyo Mine into the Williams Fork Formation was estimated to be 450 <br />feet deep. The mine face consisted of a series of steps or benches and <br />exposed many interbeds of sandstones and shales. At no time during the <br />excavation or mining processes was an appreciable quantity of water ever <br />encountered by the Colowyo Mine. In parts of the mine face, where the <br />mining process cut into a sandstone containing water, the water drained <br />from the sandstone onto the mine face or into the mine pit. The <br />discharges of water from these seeps were so small that the water was <br />consumed from the face or the floor of the pit by evaporation. This <br />condition has continued to persist over the past twelve years as the mine <br />advances . <br />The 1979 LRCWE report documented the absence of groundwater on the <br />property. This report is attached in Exhibit 7, Item 1. <br />Whereas most of the sandstones on the Colowyo Coal Company property are <br />lenticular and interbedded with shales, the Trout Creek Sandstone is a <br />regional geologic unit that can be mapped across the mine property and <br />regionally. This sandstone occurs approximately 800 feet beneath the <br />lowestmost coals to be surface mined. It is exposed to the surface north <br />of the mine property because of the uplift in the Axial Basin. The <br />sandstone is 75 feet thick and consists of white, fine-grained and well <br />sorted sand, cemented with calcareous materials. The sandstone is <br />relatively uniform across the area and can be correlated throughout most <br />of northwestern Colorado. <br /> <br />2.04.7-4 Revision Submitted 3 - z ~ - 0 1 <br />Revision Plo. T ~Z - S I <br />