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around the reservoir. Due to the steep slopes and long drop from the crest of said slopes in some <br />places, wildlife and people will need to be kept out of the reservoir area for their own safety. <br />The operator commits to clearly marking the permit boundary on site. <br />The currently existing access road will be maintained throughout the life of the mine, and will <br />remain following reclamation to facilitate access of the reservoir. <br />3.2 Blasting <br />The basalt is blasted in place using a blasthole drill which sits on a bench created by previous <br />blasting. The drill creates a series of holes which are then loaded with ammonium nitrate and <br />fuel oil. Blasting caps and delays are employed to minimize the amount of explosives used. The <br />holes are generally 5.25 inches in diameter and 38 feet deep. <br />Seismic measurements are recorded for every shot to ensure that no damage will occur to <br />surrounding properties and structures. The mine has not had any complaints of blasting damage. <br />3.3 Denver Water Tunnel <br />As shown on Maps C -1, C -2, C -3 and F, a water tunnel of approximately six feet diameter was <br />constructed many years ago by the Denver Water Board. This tunnel carries water from a ditch <br />west of the permit area underneath the permit area to Upper Long Lake Reservoir located east of <br />the permit area. This tunnel has operated for many years. <br />The mining plan will avoid this tunnel by maintaining a minimum 40 foot buffer of existing rock <br />(basalt) between the pit and the tunnel. This higher elevation will be maintained until the <br />northern end of the pit is reached, as shown on Map C -3. This area from the tunnel to the north <br />edge of the pit will not be part of the planned water reservoir. <br />4. Topsoil and Overburden Handling <br />In the undisturbed areas, the top 2 -10 feet of the mining area is covered with a topsoil material <br />mixed with sizeable basalt rocks. This material is screened for large rocks during excavation. <br />The rocks are used in the construction materials operation, and the remaining topsoil material is <br />used in reclamation. This fine material will be used as a topsoil and backfill in the final <br />Ralston Quarry, February 2015 D -5 <br />