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�46 e, <br />Picture 3 - Highwall in Pit showing Track Hoe Excavator and ramp leading to the mining pit <br />Based on the site observations and discussing performance with the operators on site, Mr. Lewicki <br />concluded that highwalls could be included in the mining operation as long as site personnel were <br />observant for any cracks, mud zones, gravel zones without cementing fines, slips, or any other <br />signs of instability. No highwall should exceed MSHA requirements and any signs of instability <br />must be addressed immediately through backfilling or other means. All past highwalls were con- <br />structed not to exceed 80 degrees from horizontal. No slope stability problems of any kind were <br />identified in any of these highwalls over a minimum of 1 year's time. Scrutiny of the cuts revealed <br />that the material above bedrock can be basically divided into 2 distinct zones: the upper zone is a <br />stiff clay that has some minor gravel and reaches a depth of approximately 40 -60 feet. None of the <br />following things were observed in this zone: slips, clay lenses, sand lenses, unconsolidated free <br />flowing material, wet unstable material. All bank material was well- cemented and held up at very <br />steep angles. Pictures 2 and 3 above show evidence of the strength of this material. <br />Gloria Z Mine TR -03 2015 12 <br />