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<br /> <br />Wildcat Mining Corporation <br />May Day and Idaho Mine and Mill Application <br />112(d) Permit – Technical Revision No. 1 <br />May Day and Idaho Mine <br />M-1981-185 <br />Revised June 30th, 2016 <br />5 <br />• Conducted physical laboratory testing soil and rock material test to support the <br />development of an appropriate restoration plan; <br />• Conducted the following analytical tests including: <br />o Moisture content and dry density; <br />o Atterberg Limits used for general classifications; <br />o Sieve analysis tests to assess the drain distribution of the samples tested; and <br />o Direct shear test to assess strength characteristics; <br />• Observed cut slope excavations to confirm the slope inclinations and material <br />physical construction characteristics. <br /> <br />Data were used to; <br />• Develop a Chief highwall and portal mitigation stabilization strategy; <br />• Designed a rock gravity wall; <br />• Performed a slope and headwall stability analysis; and <br />• Prepared a Chief and LDG drainage technical report and obtained CDRMS approval. <br />(See Technical Revision 5 Approval (Attachment 3); <br /> <br />4) Site Construction Summary (See Photos) <br /> <br />The following assessment activities were completed: <br />• Geological (Robinson-CPG-5022) and geotechnical site reconnaissance by (Rauber,-PE- <br />#26647) R Squared, Inc. March, 2012; <br />• Portal Stabilization Design; <br />• Removal of collapse material from the Chief; <br />• At the collapsed Chief portal limestone bedrock was encountered under 4 feet of <br />colluvium; <br />• The Chief was constructed in limestone; <br />• Installed a forty foot-66 inch pipe in the Chief; <br />• Installed 66 inch pipe at a 4% grade; <br />• The pipe extended approximately 10 feet beyond the lateral extent of the portal; <br />• A gravity block keyway was constructed dense/stiff colluvial material; <br />• Using gravity blocks-Chief Portal entry was stabilized; <br />• Installed a gravity wall (See Photos) <br />• Installed footings that were approximately 4 feet wide and extends at least 2 feet below <br />the finished grade; <br />• Stabilized the highwall using recommended engineering protocols and practices; <br />• Slope backfill was benched into the existing slope and compacted; <br />• Oversized rock was used to stabilize the highwall; and <br />• The stabilized fill slope above the portal is sloped approaching a grade of 1:5:1 <br />horizontal: vertical.