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Azurite,Inc. <br /> 10001 CR 12 P.O. Box 338 <br /> Cotopaxi, Colorado 81223 <br /> 719-942-4178 <br /> June 5, 2017 <br /> Danny Tezak, <br /> Byzantine Quarry LLC <br /> 1087 East Holiday Drive <br /> Pueblo West, CO 81007 <br /> RE: BYZANTINE QUARRY HIGHWALL INSPECTION, MAY 26, 2017 <br /> The writer visited the Byzantine Quarry Site on May 26, 2017 to inspect the working face <br /> and highwall condition. The strike of the limestone, limestone marl, and siltstone <br /> sequence of sedimentary rock found at that this mining site varies+- 10 degrees of N20W <br /> with dips up to 30 degree east. This conformation results in a potential for bedrock <br /> separation and failure reflected in exposed bedding plane and loose rock generated along <br /> the working face edge from the un-blasted rock face westward up to twenty feet from the <br /> highwall edge. The edge rock appears to have been cleaned of loose material during <br /> blasted muckpile removal so that any bedrock behind (west) and above the blasting <br /> pattern is removed and not left hanging along the top of the remaining highwall. The <br /> working face along the —250'length of the exposure along strike shows no slippage along <br /> bedding planes or other evidence of delamination of the bedding plane along the dip <br /> angle (30 degrees east). The working face has recently been disturbed by blasting and <br /> rock removal for crushing, exposing a 30'-40' (depending on location) highwall. As <br /> explained above, the upper edge of the highwall is angled back after cleaning of any <br /> loose bedrock dislodged by blasting of the rock immediately east of the un-blasted <br /> bedrock. <br /> The site was traversed from several directions, carefully walking out the mining benches <br /> looking for any evidence of tensional cracking or shifting of bedrock on the mine benches <br /> directly west of and above the active mining face. No cracks or other signs of bedrock <br /> movement were noted. After inspection of the working face from the lowest mining level <br /> as well as the mining benches, a careful examination of the lateral aspects of the <br /> limestone/siltstone beds was undertaken, walking through the active mining zone as well <br /> as the perimeter of the active mining zone, following east/west erosion derived shallow <br /> gullies that cut the mining area into two or three basic zones. The central and southern <br /> parts of the active mining zone are the most straight-forward and will be addressed first. <br /> As one proceeds up slope to the west from the mining face in the southern and central <br /> portion of the site, the limestone/siltstone beds are truncated by a northwest/southeast <br /> trending erosional channel that has incised the eastward dipping bedrock on the surface <br /> deep enough to expose nearly half, if not more of the unit currently being mined down <br /> dip. This means that the rock being mined at the face is not likely under much, if any, <br /> loading due to the weight of bedrock up dip from the mining area and movement of rock <br /> along the bedding plane would most likely be caused by gravity of the mass of rock <br />