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Horizontal boring and loading a conventional hole with explosives was also reviewed. This method was also eliminated because it is <br />unknown whether the charges could get to the area needed to be most effective. It was estimated we would be drilling over 180 feet in some <br />areas. <br />Rod Schuch, a Buckley Powder Blasting Engineer, and Tom Terry, PE, PG, with CTL Thompson, believe it would not take a great deal of <br />explosives to bring down the remaining scarp. As Mr. Schuch has said "what we are attempting to create is a geological failure and bring the <br />remaining slide area down. Based on the number of scarps, see CAD Drawing 2, along with the ever increasing size of the scarps, see Graph <br />1, it is thought that by placing charges directly into the existing scarps that when detonated there would be enough vibration to unhinge the <br />remaining hanging rock. <br />By referencing Photo 5, the Division can see prism 13 is located above the scarp and has been very stable since the initial slide, see Graph 1. <br />It is the area where prisms 15, 18 and 19 are located that we are interested in releasing so that the investigative process can occur <br />It should be noted that DRMS limits the vibration to 0.5 inches per second. Using the USBM formula for estimating the vibration of the blast, <br />it has been calculated by Mr. Schuch based on the following criteria; using 2,000 ft. as the distance to the nearest structure and no more than 150 lbs <br />will be detonated within 8 milliseconds. <br />.5 -1.6 <br />V = 242(D/W ) <br />WHERE: 242 = CONFINEMENT FACTOR <br />D = DISTANCE <br />W = EXPLOSIVE WEIGHT <br />Please reference Photo 6 for the distances to the closest reference points. <br />TIMETABLE: Time is of the essence and Buckley Powder can be ready within a week of the approval by the DRMS. <br />EFFECTS ON BONDING: There would be no effect on the bonding as the work would continue to be located within the current permit area. <br />Investigation of the US Forest Service land to the west of the permit area show no signs of tension cracks above the existing scarps and CTL