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3.0 METHANE MONITORING AND RESULTS <br />Locations of the four new monitoring points were selected based on the potential for the eastern <br />CBM well to be a source of methane at the site. One point was located near the former location of <br />the eastern well. A second point was installed to the east in an area of stressed vegetation, and a <br />third point to the north near Highway 12 in an area of stressed vegetation. A fourth point was <br />installed near the Toupal residence south of the former CBM well location. When monitoring <br />points AM 1, AM2, and AM4 were drilled, elevated levels of methane were detected. In addition, <br />stained soils were observed in these boreholes coincidental with the elevated methane. <br />A summary of the field analytical results is included in Table 1 and Figure 2. Concentration of <br />methane in field gas measurements from four new monitoring points ranged from 0.0 percent in <br />monitoring point AM3 near the Toupal residence to 100 percent in monitoring points AMl, AM2, <br />and AM4. Monitoring points installed in areas of stressed or no vegetation indicated high <br />concentrations of methane gas. Carbon dioxide and oxygen were also measured, and their <br />concentrations varied with the amount of methane. As methane in the soils increase, it displaces <br />oxygen and carbon dioxide, creating anaerobic conditions that result in death of vegetation and <br />staining of the soils. <br />Methane concentrations varied with depth. Monitoring point AM1 had low concentrations of <br />methane (5-15 parts per million [ppm]) from the surface to approximately 14 feet below grade. At <br />this point, a layer of cobbles was encountered that coincided with elevated concentrations (18,000 <br />ppm) of methane. <br />Additional monitoring was undertaken at the former site of the Golden Eagle Mine. This <br />monitoring consisted of the measurement of gas emanating from the former air shafr locations. A <br />valve exists to access the shaft at each of these locations. Each of the valves exhibit positive <br />pressure when opened. This flow was monitored by a Landtec GA-90 for the presence of methane. <br />At both shafrs monitored, methane levels were 100 percent. <br />Meth-(292)-11-02.doc/November 20, 2002 20 <br />