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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 <br />was to present data collected in 2003 and 2004 that quantifies the extent of impacts. In addition, the results <br />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 <br />second investigation included the installation of 7 more monitoring points at the site in June 2000. These <br />previous investigations included researching the geology of the area, a surface methane survey, researching <br />nearby coal bed methane wells, and determining groundwater extraction in the area. The coal bed methane <br />wells onsite were plugged and abandoned in late 2000. <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 27.7 percent). However, average <br />methane concentrations have increased in the 35 points monitored since the last monitoring report in 2002 <br />(.an average increase from 27.6 to 38.4 percent). Vegetation was observed to be recovering during the 2004 <br />sampling event in areas where methane concentrations had decreased. The effected area of vegetation <br />during the 2000 survey was about 146 acres whereas the 2004 effected area was about 32 acres. <br />Measurements from the former mine's south airshafr indicated that there are methane concentrations in the <br />former mine workings. The measurements indicated a concentration of 88.7 percent methane. The north <br />airshafr was inaccessible during the 2004 monitoring event. The mine workings represent a potential source <br />of methane in the area. <br />There are no inuninent 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 />293-Me[h_(7 14 A4).doc <br />