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Varra - Coulson - Fourth Stability Analysis <br />Page 2 of 3 <br />July 9, 2014 <br />Using Clover Technology's Galena v6.1 slope stability software, the Division conducted further <br />analysis of the two critical slope area configurations and mining slope combinations for the <br />Varra - Coulson Resource Project. Specific comments and requirements for each of the cross <br />sections are provided below. <br />Mine Slope with unconsolidated pit floor material <br />• Typical 1.25:1 Mine Slope with 10' offset, unconsolidated pit floor material and topsoil <br />stockpile loading <br />The Applicant's cross section was duplicated for verification with unconsolidated pit floor <br />material and with a topsoil stockpile to represent the worst case scenario for this slope <br />configuration. The safety factor produced by Galena is significantly lower (1.01) than the safety <br />factor produced by the Applicant's model (1.267). Therefore, this slope configuration is <br />unacceptable for the perimeter of the proposed site. A copy of the Galena model is attached. <br />The Applicant must revise the typical mine slope cross section by increasing the offset distance, <br />changing the mine face slope or by another acceptable method. <br />Mine Slope with bedrock pit floor material <br />Typical 1.25:1 Mine Slope with 10' offset, bedrock pit floor material and topsoil stockpile <br />loading <br />The Applicant's cross section was duplicated for verification with bedrock pit floor material and <br />with a topsoil stockpile to represent the worst case scenario for this slope configuration. The <br />safety factor produced by Galena is significantly lower (1.01) than the safety factor produced by <br />the Applicant's model (1.267). Therefore, this slope configuration is unacceptable for the <br />perimeter of the proposed site. A copy of the Galena model is attached. The Applicant must <br />revise the typical cross section by increasing the offset distance, changing the mine face slope <br />or by another acceptable method. <br />Critical Slope Area with unconsolidated pit floor material <br />Typical Critical Slope Area with 3:1 to 1.25:1 Mine Slope with 10' offset, unconsolidated <br />pit floor material and topsoil stockpile loading <br />The Applicant's cross section was duplicated for verification to represent the worst case <br />scenario for this slope configuration. The safety factor produced by Galena (1.55) confirmed <br />