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Review of Blasting Operations at Denver Brick Company's Golden Mine <br /> The intensity of this motion is 3 times lower than the 0.5 in/sec damage threshold limit. The <br /> intensity of ground motion at the areas of concern at 1700 feet or farther would not likely exceed <br /> 0.03 in/sec. Since this is the closest structure, it is clear that blast induced ground motion at <br /> nearby structures will be orders of magnitude lower than the threshold of damage. With this <br /> result, if charge weight per delay is limited to 50 pounds per delay, Stanto Group Inc concludes <br /> that blast induced ground vibration will cause no damage to adjacent property. <br /> 2.1.3 Potential for Blast Damage to Area Water Wells <br /> Based off of the surveyed water wells in the general area of the mine site, water well#1 and#2, <br /> the nearest water well is approximately 3300 feet. It is unknown the state of the water wells near <br /> the property and proposed general blast area. Information about water wells, from the Colorado <br /> Department of Water Resources, stated that the depth of water wells ranges from 355 to 703 <br /> feet and the minimum water depth is 170 feet. With overall distance considered, the wells are <br /> topographically separated from the proposed rock blasting and extraction areas, ground <br /> fracturing and excavations at Golden Mine will not interfere with the recharging capability of <br /> these water wells. <br /> Since the maximum charge per delay of 50 pounds per delay, the particle velocity of ground <br /> motion at the nearest water well (Water well#1 3300 feet) it would likely not exceed the 0.020 <br /> in/sec threshold. With these conditions, the proposed blasting location at Golden Mine will have <br /> no negative impacts on the neighboring water wells in the general area. <br /> 2.2 Potential For Damage to Traffic on Nearby Roads <br /> The area map indicates that the permitted Mining area is near Colorado Highway 93 and <br /> bounded to the North of Golden.There are no overhead power lines in the designated blasting <br /> area of the proposed mining area. The only conceivable way that the proposed blasting could <br /> impact this road is if flying rock from a blast hit them. In order to prevent any chance of this <br /> occurrence, Stanto Group Inc recommends the follow control measures: <br /> 1. No blasting should occur within 100 feet of Colorado Highway 93 road. <br /> 2. The height of inert charge stemming material will be equal or greater than the minimum <br /> blasthole spacing dimension. <br /> 3. When blasting occurs within 1,000 feet of any public roads,traffic should be cleared from <br /> the road and guards -wearing orange vests and using traffic flags should block further <br /> traffic entry at a distance of/4 mile in all directions from the blast site. <br /> By employing these cautious measures, the blasting and other mining activities at Golden Mine <br /> should have no negative impacts on adjacent roads. Colorado Highway 93 is over 1900 feet <br /> from the proposed mining area so the only real impact on the traffic would be individual cars <br /> slowing down to observe the post blast effects such as the clearing of a dust cloud or the sliding <br /> of any residual rock after a blast. <br /> 11 <br />