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' EXECUTIVE SUMMARY <br />' This report presents an annual methane monitoring summary of all activities conducted near the former <br />Golden Eagle Mine located near Weston, Las Animas County, Colorado. The objective of this summary was <br />to present data collected in 2003, 2004, 2005 and 2006 that quantifies the extent of impacts. In addition, the <br />' results presented in this report indicate a decrease in methane over time. <br />Previous investigations at the Golden Eagle Mine site included the initial installation of 28 monitor points in <br />' March 1999 to determine the extent and concentrations of methane in the shallow subsurface soils. A second <br />investigation included the installation of 7 more monitoring points at the site in June 2000. These previous <br />investigations included researching the geol--, of the area, a surface methane survey, researching nearby coal <br />' bed methane wells, and determining groundwater extraction in the area. The coal bed methane wells onsite <br />were pugged and abandoned in late <br />The average methane concentrations have shown a decreasing trend in the existing original 22 points that <br />have been monitored since March 1999 (an average decrease from 53.7 to 39.8 percent). Additionally, <br />average methane concentrations have remained nearly the same in the existing 35 points monitored since the <br />.2001 monitoring report (an average of 32.3 percent). Vegetation was observed to be recovering during the <br />2006 sampling event in areas where methane concentrations had decreased. The effected area of vegetation <br />during the 2000 survey was about 146 acres. The effected area of vegetation during the 2005 survey was <br />about 32 acres, the same as in 2004, and approximately 50.2 acres in 2006. <br />Measurements from the mine's airshafts indicated that there were high methane concentrations in the former <br />mine workings. The measurements taken from the south airshaft in 2006 indicated a concentration of 91.1 <br />percent methane. The north airshaft was inaccessible during the 2005 monitoring event because it has been <br />reclaimed. The mine workings have represented a potential source of methane in the area; however, water <br />monitoring studies indicate that the mine workings have been inundated, which should minimize any potential <br />for methane seepage to the surface. <br />There are no imminent hazards associated with the methane seepage other than stressed or dead vegetation. <br />Methane would only be a human or animal health concern within a confined space. <br />2006 Methane Monitoring Report (11.02.06).doc 11