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submittal, addressed the remaining concerns. <br />35. Confirmation is needed that actual seismic events experienced now and in the future are within <br />the range of events used in the modeling and prediction of impacts (or lack of impact) to the dam. <br />Bowie should determine a seismic "threshold event" that would trigger more detailed monitoring <br />and analysis of the dam should this threshold event occur as a result of mining. No data has been <br />submitted at this time. However, again, Jim Stover has apparently indicated that actually seismic <br />data will be submitted later this year. It should be noted that other information seems to indicate <br />that between September 1, 2004 and November 18, 2004, Bowie experienced mine induced <br />seismic events of 3.2 M, 3.3 M, and 3.5 M. The GEI analysis included one event of 4.2 and a <br />combination of smaller events, the largest of which was 2.5 M. It may be important to re-evaluate <br />the previous analysis with larger events more indicative of actual conditions. Bowie should <br />submit actual data recorded since seismic stations were brought on-line for review in conjunction <br />with this revision. <br />The Division has no further concerns. The seismic monitoring plan that was provided in Exhibit <br />18 of Volume IIIA of the May 12, 2008 submittal was reviewed and is acceptable. <br />36. The Division does not concur with conclusion #7 of the June 2002, GEI report that's states <br />"additional monitoring of the dam and saddle dam ... is not required to address risks associated <br />with mine-induced seismicity. " The Division concurs with the SEO that seismic monitoring is <br />required at the Bruce Park Dam as mining moves inside a one-mile radius of the dam. Without <br />actual monitoring data to compare to pre-mining analysis and conclusions reached, we cannot <br />evaluate the adequacy of any seismic monitoring plan at this time. Bowie should submit actual <br />data along with permit text clearly stating a seismic monitoring plan for the Bruce Park Dam. <br />It is the Division's understanding that the Division of Water Resources will request, in a <br />forthcoming letter, that BRL present a monitoring program for the Bruce Park Dam. When the <br />Division receives this letter from the Division of Water Resources, it will be forwarded to BRL. <br />If you have any questions, please call me. <br />Sincerely, <br />,,Joseph J. dash <br />Environmental Protection Specialist <br />Attachments <br />cc: Jim Stover P.E. (J.E. Stover & Associates) with attachment <br />Ryan Taylor (USDA-Forest Service) with attachment <br />11