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report. They are located approximately 1000 feet south of the study area. The <br />two gate entries terminate at the anomaly. <br />2. Two Coal Bed Methane (CBM) Wells are located within the study area. <br />These were plugged and abandoned in October of 2000. The Colorado Oil and <br />Gas Conservation Commission (COGCC) concluded in late 2000, that "the <br />gas wells are definitely not the source of the methane seep". <br />Since these studies were initiated, two events have occurred that may have impacted the <br />presence of methane gas within the study area: <br />1. The two CBM wells were abandoned in late 2000. This was followed by an <br />observed general decline in methane concentrations after 2000. <br />2. Since closure of the mine in 1996, the mine workings have been flooding. Water <br />levels flooded the 1-Right and 2-Right area during 2002. Rising water levels may <br />have trapped and pressurized the methane present in the two sections gradually <br />forcing the remaining methane gas into the strata This may be the mechanism <br />that caused an increase in methane concentrations in the study area in 2003 prior <br />to the resumption of declining methane levels in 2004 and 2005. (All but the <br />extreme southern portions of the mine are now flooded. The water levels in the <br />mine rose 10.9 feet in 2004 to an elevation of 6820, approximately 423 below the <br />surface level of the South intake air shaft.) <br />Assmning that mine dewatering was a primary causal factor in the presence of <br />methane in the study area, the downward trend in methane concentrations should <br />continue until soil gas concentrations return to normal. <br />A concern is the potential effect that co~nued Coal Bed Methane development may have <br />on the study area Methane migration to the surface has been observed in at least two <br />locations east of the study area: <br />1. Methane gas has been observed bubbling to the surface in the creek in Cow <br />Canyon approximately six miles east of the Golden Eagle Mine. <br />2. Methane accumulations were recently detected in a home, buildings and alfalfa <br />field near Madrid about twelve miles east of the mine site. The incident is being <br />investigated by the COGCC and reportedly monitoring and ventilating devices <br />were supplied by COGCC and the CBM well developer. The home has since <br />been condemned and the occupants relocated. <br />CBM well development is continuing in both areas and also around the methane study <br />area. The effect it may have on the study area is unknown. <br />Conclusion <br />No single factor has been identified as the causal factor contributing to the presence of <br />methane in the study area If strata dewatering caused by mining related activities were a <br />primary contributing factor, then mine flooding will contribute to the continued decrease <br />in methane concentrations and a return to normal soil gas ogna~tp~pops. <br />