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recommended maximum particle velocity of 2 in/s, the above equation yields a scaled distance of 15.3. <br />Thus, a 6,500 -Ib charge weight could be used at distances greater than 1,230 ft. When the blast area is <br />nearer than 1,230 ft, the charge weight must be reduced (according to the above equation or the 15.3 <br />minimum SD limit) to maintain a safe vibration level. The predicted vibration level should be calculated <br />prior to each blast and charge weights should be reduced (if necessary) to make sure the vibration level is <br />below the recommended 2-in/s limit. Additionally, AAI recommended that vibration data be measured at <br />the rock art site to confirm that the above equation accurately predicts actual rock art site ground vibration. <br />Trapper proposes to use the above equation recommended by AAI for designing production blasts near <br />the rock art site and to continue to measure ground vibration at the site. <br />3.4.4 Records <br />The record will contain the following information (refer to Figures 3.4-2 and 3.4-3): <br />1. Name of operator conducting the blast. <br />2. Location, date and time of blast. <br />3. Name, signature, and license number of blaster and the names of blast helpers present. <br />4. Identification, direction, and distance, in feet, from the nearest blast hole to the nearest dwelling, <br />school, church, or community or institutional building either, a) not located in the permit area, or b) <br />not owned or leased by Trapper Mining Inc. <br />5. Weather conditions, including temperature, wind direction and approximate velocity. <br />6. Type of material blasted. <br />7. Number of holes and spacing. <br />8. Diameter and depth of holes. <br />3-32 <br />Om• <br />