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RE. J-2 Contracting Company—DPG Pit—Permit No. M-2019-028 <br /> 112(c)Permit Application <br /> Adequacy Review No. 1 Response 8126119 <br /> -15- <br /> advised, the Division considers the majority of the structures located on or within 200 <br /> feet of the proposed affected lands (including all structures assessed in the slope <br /> stability report) to be critical structures. Therefore, please revise the report to include <br /> design criteria based on a FOS of 1.5 for static conditions and a FOS of 1.3 for <br /> analyses using seismic parameters. <br /> d. The report lists four recommendations for monitoring of slope stability, including, <br /> conducting a visual inspection of the excavated slopes on a weekly basis for the <br /> duration of mining, conducting a visual inspection after a major precipitation event <br /> that has saturated the ground using the same procedures, contacting qualified <br /> personnel to evaluate and recommend remediation work to stabilize the area in the <br /> event a visual inspection detects signs of potential slope failure, and if no visible <br /> signs of slope failure are detected during mining, reducing visual inspections to once <br /> every six months after mining completion, or after every major precipitation event. <br /> Please incorporate these recommendations into the proposed mining and <br /> reclamation plans. <br /> Response: <br /> a. An agreement with DPG Farms, LLC is attached. For all the structures not owned <br /> by DPG Farms, LLC within mining phases there are several that are in the process <br /> of being abandoned and J-2 Contracting Company is actively working with these <br /> structure owners to determine when they will be abandoned. J-2 Contracting <br /> Company commits to not mining within 200 feet of the structures not owned by <br /> DPG Farms, LLC that are within the mining phases until the structure owner <br /> abandons and removes them from the mining phases. <br /> b. For all the structures not owned by DPG Farms, LLC within mining phases there <br /> are several that are in the process of being abandoned and J-2 Contracting is <br /> actively working with these structure owners to determine when they will be <br /> abandoned. J-2 Contracting Company commits to not mining within 200 feet of the <br /> structures not owned by DPG Farms, LLC that are within the mining phases until <br /> the structure owner abandons and removes them from the mining phases or an <br /> agreement is in place. A copy of any agreement once it is in place will be provided <br /> to the DRMS. The other structures that are outside the mining limits have slope <br /> stability cases that are associated with the worst case scenario based on the <br /> proximity to the top of slope of the mining and the setbacks have been determined <br /> and updated to meet the factors of safety required by the MLRB Policy. <br /> c. The slope stability models have been revised and updated. The setbacks have <br /> been determined and updated to meet the factors of safety required by the MLRB <br /> Policy. <br /> d. J-2 Contracting Company commits to incorporating the recommendations for <br /> monitoring the slopes of the mining from the slope stability study into the mining <br /> and reclamation plans. <br /> Additional Item(s): <br /> 55) Pursuant to Rule 1.6.2(1)(b), the Applicant shall provide a signed affidavit with the <br /> application that notice signs have been posted at the location of the proposed mine site <br /> jq <br /> 1 305 Denver Avenue-Suite D•Fort Lupton CO 80621 •Ph: 303-857-6222•Fax:303-857-6224 <br />