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' _ _ _ 4.0 CONCLUSIONS <br />Methane <br />characterization was performed east of the Golden~Eagle Mine in Weston, Colorado, to <br />measure methane concentrations in an area of stressed and dead vegetation and to define the <br />' potential extent of subsurface methane gas. <br />This assessment included the installation of four monitor points. Concentration of methane ranged <br />from 0.0 percent in monitoring point AM3 to 100 percent in monitor points AMI, AM2, and <br />AM4. Monitoring point AM4 is located on the south side of Highway 12, east of the area of <br />stressed and dead vegetation. The monitoring results indicate that the methane impact is to the <br />competent bedrock in monitoring points AM2 and AM4, which indicates the source of the methane <br />is below the alluvium, and is therefore from the bedrock. <br />' Measurements from the former mine shafts indicate that concentration of methane exist in the <br />former mine works. The measurements indicated a concentration of almost 100 percent methane. <br />' The methane from the shafts was emanating under pressure. The mine works represent a potential <br />source of methane in the area. However, since the two CBM wells have been reclaimed in October <br />2000, levels of methane in the surface soils have been decreasing. <br />Finally, graphs of data collected from the monitoring wells from year 1999 to year 2002 indicate <br />an overall decrease in the concentration of methane (Appendix A). <br />Metlr-(292)-11-02.doc/NOVem6er 20, 2002 21 <br />