2013-02-22_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 newly constructed highwall slopes should not exceed 80 degrees from horizontal. Depths above 60 feet vertically may require benching. 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 and the highwall will eventually be filled in from the ongoing processing. It is, however, understood that the highwall must be bonded for the worst case, which is the current condition. This current highwall at the infiltration pond will require 12,000 cubic yards to backfill to the ac- cepted post -mine land use of rangeland. A swale may be left in the landscape but no slope will be steeper than 4H:1 V. Gloria Z Mine 2013 Amendment 11