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reconstructions of each of the blasts detonated during this period to determine the <br />maximum peak particle velocities achieved in the azea of the landslide, and to determine <br />compliance with the maximum weight of explosives regulatorily allowed to be detonated <br />within any 8-millisecond period within each blast. The geotechnical and engineering <br />analysis should include a determination of whether ground vibration from blasting <br />contributed to, or otherwise had an etI'ect upon, the landslide. <br />RESPONSE: We have already provided you with the blasting records <br />you request. The blast diagram and other information on the shot <br />reports should provide the data necessary to address the topic identified <br />in your second sentence. We do not know at this point whether it will be <br />possible to determine to a reasonable degree of certainty what effect, if <br />any, ground vibration may have had on the landslide. We will include <br />our current impressions on this topic and on the feasibility of reaching a <br />definitive conclusion regarding it in Phase II of our report. <br />• The effects of water and hydrostatic pressures upon the landslide. This should include <br />precipitation data collected at the Trapper Mine between September 1, 2006 and October <br />8, 2006, and a determination as to whether precipitation contributed to, or otherwise had <br />an effect upon, the landslide. <br />RESPONSE: A 100-year storm event on September 16th dropped 2,34 <br />inches of precipitation in 24 hours, coupled with another 1.48 inches of <br />precipitation between September 16th and the day of the slide (October <br />8th) undoubtedly contributed to the slide. We do not know at this point <br />whether it will be possible to determine to a reasonable degree of <br />certainty the total impact on hydrostatic pressure the precipitation may <br />have had on the landslide. We will include our current impressions on <br />this topic and on the feasibility of reaching a defuutive conclusion <br />regarding it in Phase II of our report. We will provide precipitation data <br />to you by not later than December 8, 2006. <br />• The failure surface/zone within the stratigraphy of the landslide azea. Please determine <br />how this failure surface/zone may have contributed to the landslide. <br />RESPONSE: We do not know at this point whether it will be possible to <br />identify to a reasonable degree of certainty the failure surfacelzone <br />within the stratigraphy of the landslide area. We will include our initial <br />impression on this topic in Phase I of our report. We will update our <br />analysis in that respect in Phase II of our report, and provide then our <br />opinion on the feasibility of reaching a definitive conclusion regarding <br />that topic. We also do not know at this point whether it will be possible <br />to determine to a reasonable degree of certainty what effect, in any, this <br />failure surface/zone had on the landslide. We will include our current <br />impressions on this topic and on the feasibility of reaching a definitive <br />conclusion regarding it in Phase II of our report. <br />• The structural geology of the slide azea. Please determine how the structural geology may <br />have contributed to the landslide. <br />2 <br />