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• <br />PreSe~sTe k 8174 S. Holly St., Suite 402, Centennial, CO 80112-4004 <br />3~~'CERTj~'cd <br />;~J <br />Na[iooal Women Bisinss <br />Owrxrs Corporation <br />August 28, 2006 <br />Attention: Ed Benson <br />21240 Austin Road <br />Austin, CO 81410 <br />ny Phone: 303-324-4116 Fax: 303-488-0053 <br />Email: saranation@preseistek.com <br />RE: Review and Analysis of measured ground motions caused by excavator, doers and <br />operating crushers. <br />Background and Introduction <br />PreSeisTek, Inc. (PreSeisTek) was retained by Benson Brothers and Revey Associates to <br />• collect vibration data at the Benson Brothers Red Shale Quarry in Austin Colorado The <br />purpose of the data collection is to determine the level of vibration occurring in the <br />Quarry area specifically at the rock bluffs above the Croissant property and other area <br />property. <br />On Tuesday July 15th, 2008 at approximately 9:00 a.m. PreSeisTek began setting up one <br />(1) White Seismology seismograph at Global Positioning Station (GPS) N- 38'55.720, <br />W- 107'58.179 on the Quarry site. The unit Serial number 932 had been calibrated within <br />one (1) year. The unit was set up in bargraph mode to pulse every 6 seconds for vibration <br />between the hours of 8:00 a.m. and 5:00 p.m. for 30 days. At the same time PreSeisTek, <br />Inc. conducted a study at the site colleting vibration data at 5 different locations while the <br />heavy equipment was running. The quarry was shut down while parts (high pressure <br />relief valve and accumulator) were ordered for the cone crusher between July 16th and <br />July 23rd. During this time the seismic equipment did not collect data. <br />Location of Seismograph <br />It should be understood that the placement of the unit was decided based on the collection <br />of data that was collected in the study where 5 different locations were monitored for <br />vibration. This site was selected at a distance of at least '/z mile from the rock bluffs so <br />• that data could actually be collected. Had we moved the unit closer to the bluffs we <br />