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2801 Youngfield Street, Suite 171 <br /> Matheson Golden, CO 80401-2266 <br /> 303-456-5638 <br /> Mining Toll Free 888-456-5638 <br /> Consultants Inc. Fax onmini 6-5639 <br /> � www.mathesonmining.com <br /> February 15, 2016 <br /> Mr. Michael Coleman <br /> President, ACA Products, Inc. <br /> P. O. Box 1887 <br /> 702 Gregg Drive <br /> Buena Vista, CO 81211 <br /> RE: Trout Creek Quarry Blasting <br /> Dear Mr. Coleman, <br /> Matheson Mining Consultants, Inc (MMC)has reviewed the report"Evaluation of Effects and <br /> Recommended Controls for Blasting at the ACA Products, Inc. Trout Creek Quarry in Chafee <br /> County, Colorado'by Revey Associates, Inc. dated July 2001. The report is thorough and well- <br /> reasoned. The recommendation of a Scaled Distance of 15.5 to keep Peak Particle Velocity <br /> below 3.0 inches per second provides a high degree of protection for the dam. <br /> Current blasting is approximately 600 feet from the dam, using a Scaled Distance of 15.5 would <br /> allow 1498 pounds per 8-millisecond delay period. ACA proposes using no more than 500 <br /> pounds per delay, which at 600 feet equates to a scaled distance of 26.8 and using Revey <br /> Associates Equation 2.2 on page 6 of the report the estimated particle velocity is 1.24 inches per <br /> second. <br /> MMC recommends measuring the blast effects at the foot of the dam and keeping vibration <br /> below 3.0 inches per second. Allowing blasting at a scaled distance of 26.8 will keep the blast <br /> effects well below the proscribed limit. <br /> MMC recommends allowing ACA to design blasts and the maximum charge weights per 8- <br /> millisecond delay using the logic as outlined in the Revey Associates, Inc. report as long as the <br /> blast effects are measured at the dam. <br /> Sincerely, <br /> A- <br /> Colin Matheson <br /> President <br />