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ALBERT FREI AND SONS, INC. Page 2 <br />HATCHERY PIT Permit # M- 2014 -043 <br />As an additional safety consideration we decided that to <br />keep all potential impacts within the permit /affected land line <br />we moved the mine face digline to 50 feet. This makes the <br />distance from the toe of the working face slope to the structure <br />60 feet and the slope angle 24.7° (red line). The resulting FS = <br />1.52 and provides adequate protection for all off site structures <br />around the dry mining area. Should the slope fail when the dig <br />line is set at 50 feet the final top of slope would be 11 feet <br />inside the permit area <br />As mining approaches the perimeter of the mine a 25 foot <br />mining setback will be staked from the permit line to establish <br />the mining limit. An additional safety setback of 25 feet will <br />be staked from the mining setback line to establish the limit <br />that mining with a near vertical face will stop. <br />As shown above, by using the setback proposed the safety <br />factor for the closest structure will be 1.52, so by reason, as <br />you move away from the mine face the greater the safety factor <br />would be for any structures within 200 feet of the permit line. <br />