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other concerned agencies and parties are working with the same information. <br />In the submittal dated December 28, 2006, BRL provided a Microseismic Monitoring Report for the <br />3rd quarter of 2006 in Exhibit 18 of Volume IIIA. The Microseismic Monitoring Report for the 4th <br />quarter of 2006 was submitted to the Division on March 12, 2007. The Division has reviewed both <br />reports and has the following comments on the report format. <br />A. The report should contain a clear description of the ultimate objective of the seismic <br />monitoring program, the methodology used to gather, analyze and report the data in support of <br />the objective, a description of the threshold monitoring program, a comparison of the data to <br />the threshold limits and conclusions as to whether or not the objective is being achieved. <br />B. The Microseismic Monitoring Report for the 4'h quarter of 2006 presents information for the <br />entire seismic network, which includes both the Bowie No. 2 Mine and the West Elk Mine. <br />The inclusion of West Elk Mine data into a Bowie No. 2 Mine report appears to be <br />unnecessary. Is it possible to briefly describe the entire network at the beginning of the report <br />but to, then, filter out the West Elk data in the rest of the report so that only the Bowie No. 2 <br />Mine is presented and discussed? <br />C. The Division would like to see a clearly-stated summary description of the <br />mining activity during the report period in relationship to the reservoir, dams and landslide. <br />D. The Division would like to see the actual field data presented in the report in the form of a <br />table. The table data might include date of event, event number, epicenter location, event <br />magnitude, station location, station distance from epicenter and the acceleration at the station. <br />If possible, a note might be added to each event that indicates whether the event was mine <br />induced or natural. Consistent units should be used throughout the report. As an example, <br />currently, magnitude and acceleration are both used. <br />E. Maps and figures should be presented at a larger scale with more detail. Cross sections would <br />be helpful, especially for events that occur in close proximity to the longwall and are recorded <br />by stations that are relatively close to the seismic source/longwall position. <br />F. Depending on the mine plan, some station locations may be of more interest due to their <br />proximity to current mining and may be deserving of additional analysis and report <br />discussion. <br />G. A discussion of the results of the analysis of the data, the relationship between the data <br />analysis and the threshold triggers, how the data compares with previous data and whether the <br />data supports the initial prediction. <br />H. The reporting format should be flexible enough to allow for changes as more data is gathered <br />and more is learned about seismicity in the area. <br />In the introduction to the Microseismic Monitoring Report for the 4`h quarter 2006, it is stated <br />that "Some seismological aspects of the analysis are not yet completed. The velocity model, a <br />ground-motion attenuation model, station delay times and network magnitude definitions are <br />under construction." Please advise the Division as to the status of these efforts and when the <br />seismic monitoring and analyses system will be fully operational. <br />8