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<br />0 INTRODUCTION <br />This report is prepared by David Butler, Senior Geophysicist, Zonge Geosciences, Inc., Lakewood, <br />Colorado, in partial fulfillment of a commitment by Bowie Resources LLC (BRL) to monitor the <br />microseismic activity near longwall mining activity at the Bowie No. 2 mine just east of Paonia, <br />Colorado. This commitment is to the Colorado Division of Natural Resources, Division of <br />Reclamation, Mining and Safety. <br />The five stations specific to the Bowie monitoring network are located in T12 and 13 S, R91 W, North <br />of Colorado State Highway 133 (see Figure 1). The area encompassed by the ten stations of the <br />combined network extends east-west from Coal Creek Mesa to West Tower Mountain and north- <br />south from Terror Creek Reservoir to Lion Mesa. The larger area includes West Elk coal mine <br />operated by Mountain Coal Company, LLC and Bowie No. 2 Mine, property of Bowie Resources, <br />LLC (BRL). Seismicity from the Elk Creek mine owned by Oxbow Mining, Inc. is also recorded. <br />This report contains preliminary analyses of data collected in the fourth quarter of 2006, i.e. from <br />October to December, 2006. Stations in the network operated previous to this quarter, but this <br />report contains only information about the fourth quarter of 2006. Some seismological aspects of <br />the analysis are not yet completed. The velocity model, a ground-motion attenuation model, <br />station delay times and network magnitude definitions are under construction. Further <br />development of these parameters and models will lead to refinement in the calculated event <br />location coordinates and magnitude estimations; however, the basic record of the seismic activity <br />is will remain unchanged. This report focuses on progress towards seismologic conclusions <br />completed during the analysis period. <br />The seismic monitoring program was designed to monitor seismicity levels, provide locations for <br />local events, measure ground motion quantitatively, determine focal mechanisms when feasible, <br />and establish the ground motion regime that structures within the network are and will be subject <br />to during mining. <br />OPERATIONS <br />Station Locations and Descriptions <br />A multi-station seismic array (10 stations) was installed by a cooperative effort of MCC and BRL <br />and the Spokane Research Laboratory of NIOSH/CDC (National Institute for Occupational Safety <br />and Health/Centers for Disease Control and Prevention). Station locations were determined by <br />consideration of access, permission of landowners, specific array geometry, radio line-of-sight to <br />the common recording site (the Paonia Airport) or a repeater station and uniform coverage of the <br />target area (see Figure 1). <br />The location of stations presently operating are shown on Figure 1 and corresponding station <br />coordinates are listed in Table 1.