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Some of these features were on previous iterations of the mine plan map but were <br />left off the latest version. Please revise the map to include these Features. <br />3. The stability analysis that was submitted to address mining within 200 feet of <br />structures where no damage agreement has been reached, indicates that at 2H:1 V <br />slopes, the safety factor was less than 1.25. These calculations were apparently <br />processed using the most conservative assumptions available for the type of <br />material that is being mined. Unfortunately, this demonstrates that not only could <br />the identified structures not safely be mined to within 200 feet, the post-mining <br />slopes of 2H:1 V would also be unstable. Therefore, actual field data must be <br />gathered to use in the analysis. If the properties from field samples are such that a <br />higher safety factor can be achieved, that will solve the problem. However, if the <br />safety factor is still unacceptable after utilizing real data, the slopes may have to <br />be modified as well. In any event, a demonstrated safety factor of 1.25 or greater <br />must be met for all post-mining slopes as well as slopes that will be closer than <br />200 feet of a structure without a damage agreement. <br />4. There are still several structures for which no damage agreement has been <br />provided and a stability analysis has not been provided to demonstrate that mining <br />could safely occur within 200 feet of such structures. These structures include <br />power lines, oil and gas well heads and collection lines and facilities, etc. There <br />must be an agreement or satisfactory stability analysis for these structures or the <br />office approval must stipulate a 200 foot mining off-set from these structures. <br />5. Part of the proposed wetland mitigation would be to introduce water <br />corresponding to Last Chance water shares and owned by the operator into the <br />slough via the Side Hill Ditch. However, there is presently not a diversion head <br />gate that would allow for this to occur. It was indicated that positive preliminazy <br />discussions have been held with the Last Chance Ditch Company concerning <br />installation of a new head gate which would allow water to be diverted into the <br />slough. In order for this application to be approved, a new point of diversion (ie <br />head gate, pump location, etc) must be installed or a legally binding agreement <br />between the ditch company and Owens Brothers for a future installation must be <br />submitted. <br />6. We still have not received confirmation of a gravel pit type well permit or <br />augmentation plan and substitute supply plan from the State Engineer's Office. As <br />previously mentioned, if this information is not received prior to a decision from <br />our office, the site will be bonded for total backfill or stipulated to prevent <br />groundwater exposure. <br />