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Mayo and Associates, LC <br />li <br />'~ <br /> <br /> <br /> <br />J <br />'~ <br />J <br />Personal Communication, 1997). Groundwater dischazge rates from other locations on <br />the Pleasant Valley Fault aze also small but aze more constant. <br />Groundwater dischazging from the Pleasant Valley Fault is of ancient origin. Water <br />issuing from 6W X 20, MN-ME, and 1.SN X 29 have14C ages of 2,000, 7,000 and 4,500 <br />years, respectively (Mayo and Associates, 2001). The recession hydrograph for MN-ME <br />(Figure 9) shows that discharge has steadily declined from about 0.5 to 0.2 gpm over 4 <br />years. <br />3.2.3.2 Roans Canyon Fault <br />The Roans Canyon Fault systems, forms a narrow graben in the central portion of Trail <br />Mountain and in the northern portion of East Mountain. The fault system roughly <br />pazallels the Straight Canyon Syncline and appears to be scissor faults hinged neaz the <br />center of Trail Mountain (Figure 10). At the hinge location there is essentially no vertical <br />or horizontal displacement. Maximum displacement on the faults in the lease area is <br />estimated to be 160 feet (Semborski, Persona] Communication, 1997). The Roans <br />Canyon Fault was first encountered in the Deer Creek Mine in a series of horizontal drill <br />holes completed in 1985. A second series of horizontal drill holes penetrated the fault <br />system in 1989. Limited lateral communication along the fault system was suggested by <br />the fact that dischazge from drill holes located only 200 feet apart did not significantly <br />affect the dischazge rates of the individual holes. <br />Evaluation of Potential Groundwater Inflows 34 <br />Associated with E Seam Mining, <br />West Ells Mine, Somerset, Colorado <br />February 24, 2004 <br />