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Aaency Responses <br />3 ] . In Technical Revision No. 22 (TR-22), BRL proposed to incorporate a geotechnical data report and a <br />seismic monitoring plan into the Bowie No. 2 permit application. Because ofoutstanding adequacy <br />issues, TR-22 was withdrawn on August 18, 2003. However, two unresolved issues from TR-22 are <br />sill relevant to the adequacy review far PR-10. <br />A. /n TR-22, the Division requested that a demonstration be made that the modified earthquake- <br />generated seismic signal used in the Bruce Park dam seismic analysis reasonably <br />approximates a seismic signal generated from longwall mining at the Bowie Na. 2 Mine. <br />Please provide such a demonstration. <br />In the response letter dated December 28, 2006, BRL stated that the site generated seismic <br />signal will be different from that used in the GE[ report but would appazently result in vertical <br />accelerations significantly Tess than those predicted in the GEI report. However, the GEI <br />report used a modified north-south component of the EI Centro, California earthquake of <br />1940. The Division believes that asite-specific mining-induced seismic signal could possibly <br />be more reliable since this entire project hinges on the results of the GEI report. This site- <br />specific seismic signal could be from the Bowie No. 2 Mine or possibly from the West Elk <br />Mine, as suggested in the USDA-Forest Service letter dated February 22, 2007 letter. <br />Therefore, the Division requests that the GEI report "Geotechnical Evaluation of Mine- <br />[nduced Seismicity on Bruce Park Dam" be updated with asite-specific seismic signal. <br />B. In the TR-22 review, the Division received a letter from the Colorado Division of Water <br />Resources (DWR), dated June 11, 2003, in which additional information was requested <br />concerning the landslide immediately adjacent to the Bruce Park main dam. A copy of this <br />letter is attached. Please submit these data and report, per the recommendations described in <br />the DWR letter of June 1 /, 2003, as part of the adequacy review for PR-10. <br />In a submittal dated November 14, 2006, BRL provided a report by Yeh and Associates <br />entitled "Final Geotechnical Investigation and Evaluation Report- Bruce Park Landslide". <br />The Colorado Division of W ater Resources has reviewed this report and their comment letter <br />is attached. <br />32. The Division has received several comment letters from various governmental agencies and <br />organizations concerning the activities proposed in PR-]0. Some of these comment letters have <br />already been forwarded to BRL. Attached to this adequacy review letter are copies of all of the <br />comment letters. Issues brought up in these comment letters that relate to the Division's jurisdiction <br />have a corresponding question or comment from the Division as well. The following are the comment <br />letters that are attached: <br />A. Letter, dated March 15, 2006, from the Colorado Historical Society, <br />B. Letter, dated March 20, 2006, from the U.S. Department of the Interior Bureau of Land <br />Management. <br />C. Letter, dated March 20, 2006, from the US. Department of the Interior Office of Surface <br />Mining. <br />10 <br />