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This close-up photo shows the dramatic ddference of methane-contaminated sods vs native vegetation <br />Gas analysis <br />Samples of coal bed methane well gas, mine gas. and sort monitoring gas were taken and tested for isotope <br />characteristics. These tests were inconclusive and provided no clear mdlcation of the source o} the gas In the <br />sod profile. <br />Hypothesis <br />A number of assumptions must be true in order for methane gas to contaminate surface soils <br />Is there a source or reservoir for the methane m the immediate area? The answer is yes Presence of methane <br />In the subsurface has long been Identified and researched m numerous papers and reports The presence of <br />methane in the subsurface in the area of interest has been proven through both mrning and dnning. Gas lids m <br />shallower horizons have been confirmed through drilling activities and contamination around well LA 218 also <br />confirms the presence of gas in the rocks above the Maxwell coal seam. Methane is commercially produced in <br />the immediate vicinity. Large volumes of water exert the pressure necessary to keep the methane confined m <br />the micropores of the coal. This water must be removed before the methane Is free to flow. Both drilling <br />activities and mining can remove water pressure allowing methane to move <br />Is there a pathway of migration for subsurface methane to reach the surface in the area? Again, the answer Is <br />yes. Drill holes confirm fracturing in the subsurface at a depth of 400-500 feel Faulting may reach the surface <br />but is not visible due to geology of the region (poor bed correlation) Improperly completed gas welts, completed <br />water wells, and coal exploration boreholes in the area have been positively confirmed as conduits for methane <br />to reach the surface. One of the improperly completed gas walls (now abandoned) Is located in the south :S of <br />section 28. <br />Are there other potential explanations for methane in the sods? The answer is no, Landfills can produce <br />methane due to the decomposition of organic matter No known landfills exist In the rmmed~ale are of <br />contamination, Gas pipelines do cross the affected area. Verbal communication during the investigation <br />Indicated the lines were checked for leaks and no leaks were found. Since these lines are commeraal and <br />currently in use, leak testing end awareness should have identified any past leaks and correct any current leaks <br />If discovered. Even d a pipeline leak was suspected, the elevation of much of the vegetation die-out could not <br />be explained by a gas leak In a pipeline at a higher topographic elevation. <br />6 <br />