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Results-Locations <br />For a selected set of the larger events preliminary locations and magnitudes were calculated. <br />These locations are shown on Figure 3. Though the locations are preliminary and the sample is <br />not exhaustive, two distinct areas of activity are present, one WSW of station FGH and one ENE <br />of station FGH. Ony four located events fell outside of these two areas; one event is located near <br />the reported MCC mining activity. but the other three are several kilometers from the mining <br />activity in the quarter. Note that the accuracy of the locations for these events which are outside a <br />subarray (no station within 2.5 km) is less than for the other events. <br />Ground motions (including time histories) with peak accelerations of several g's were used to <br />evaluate the Bruce Park Dam(GEI Consultants, 2002). The dam was judged to be safe under <br />such seismic loading. <br />These results are based on the preliminary analysis of a sample of the data. <br />CONCLUSIONS The seismic network is in place and operational. The seismic activity in the <br />North Fork Valley is being recorded and the larger events are processed in a preliminary fashion. <br />References: <br />Huzjak, Robert J., 2002, Geotechnical evaluation of mine-induced seismicity on Bruce Park Dam, <br />Delta County, Colorado, 2002, GEI Consultants, Inc., Englewood, Colorado 80112. <br />Swanson, P. and W. Koontr, Measurement and Analysis of Mining-Induced Seismic Ground <br />Motion in the ViGnity of the West Elk Coal Mine, Somerset, CO (abstract), Seism. Res. Lett., v. 77, <br />no.2, p. 318, 2006. <br />Thatcher, Wayne, 1973, A note of discrepancies between local magnitude (ML) and <br />microearthquake magnitude scales, Bull. Seis. Soc. Am. 1973, v. 63, no. 1, p. 313-318. <br />