2013-05-20_REVISION - M1984094 (7)

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Based on the site observations and discussing performance with the operators on site, Mr. Lewicki concluded that highwalls could be included in the mining operation as long as site personnel were observant for any cracks, mud zones, gravel zones without cementing fines, slips, or any other signs of instability. No highwall should exceed MSHA requirements and any signs of instability must be addressed immediately through backfilling or other means. All past highwalls were con- structed not to exceed 80 degrees from horizontal. No slope stability problems of any kind were identified in any of these highwalls over a minimum of 1 year's time. None of the following things were observed: slips, clay lenses, sand lenses, unconsolidated free flowing material, wet unstable material. All bank material was well- cemented and held up at very steep angles. All newly con- structed highwall slopes after Amendment approval in 2013 should not exceed 45 degrees from horizontal. This milder angle will be more than adequate for the life of the pit. The operator will still be required to observe the excavation for any signs of instability but it is not expected that there will be any. Depths above 60 feet vertically may require benching if any signs of instability EsT&WIP -1111 It appears that there is a zone of some gold in the gravel from the surface to a depth of approxi- mately 20 -30 feet, followed by a barren gravel zone of 30 -40 feet followed by a zone of up to 25 feet that contains a higher percentage of gold. The barren zone will be used to backfill previous pits and the other material will be sent to the plant for processing. Some of the washed gravel will also be used for backfilling and other material may be further crushed and screened for gravel product sale. Once the initial pits have been excavated, barren material and washed gravel will be used to back- fill previous pits. The maximum amount of pit that requires backfilling will be limited to 20,000 cubic yards. A current highwall (start of 2013) of approximately 60 feet height will be implemented at the south end of the infiltration pond. This pond will later become the settling pond for the processing plant Gloria Z Mine 2013 Amendment 12