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■NewFields <br /> Perspective.Vision.Solutions. <br /> TECHNICAL MEMORANDUM <br /> 9400 Station Street <br /> Suite 300 <br /> Lone Tree,CO 80124 <br /> T:720.508.3300 <br /> F:720.508.3339 <br /> To: Newmont Mining Corporation <br /> From: NewFields Mining Design &Technical Services <br /> Project: Stage 2A—VLF2 Risk Reduction Study <br /> Project No: 475.0106.009 <br /> Subject: Nonagglomerated Tailings Strength Assessment and Stability Evaluation - Rev 2 <br /> Date: 1 June 2017 <br /> ...........................................................................................-......................--.................................................---............................. ................. <br /> 1.0 INTRODUCTION <br /> Newmont is considering removal of the existing agglomerator in the High Grade Mill at the <br /> Cripple Creek & Victor Gold Mine (CC&V). The current operational permit specifies that tailings <br /> are agglomerated prior to mixing with virgin ore and placement on the leach pad. NewFields <br /> was requested to assess if the placement of nonagglomerated tailings in the Squaw Gulch <br /> Valley Leach Facility (SGVLF) influences the global stability of the pad. For this study, NewFields <br /> performed testing on a variety of ore and tailings blends primarily to assess their shear strength <br /> and compare the results to the existing shear strength data for the ore. Ore samples from both <br /> the Cresson and Wild Horse Extension (WHEX) pits were obtained and evaluated, along with <br /> tailings from the process circuit. NewFields subsequently evaluated global stability by <br /> determining minimum shear strength of heap leach material (ore or ore/tailings mixtures with a <br /> maximum of 10% tailings) to achieve acceptable factors of safety for SGVLF. The laboratory <br /> testing and stability evaluation are summarized in this Technical Memorandum, along with our <br /> recommendations for future operation of the leach facility. <br /> 2.0 LABORATORY TESTING AND RESULTS <br /> Laboratory tests were performed on a variety of virgin ore and ore/tailings blends to determine <br /> material characteristics and shear strength properties. Ore 1 and Ore 2 come from the Cresson <br /> and WHEX pits, respectively. Based on information provided by CC&V, an approximately equal <br /> ratio of Cresson and WHEX ore will be mined and placed in the SGVLF during the year of 2017. <br /> The nonagglomerated tailings were mixed with each type of ore at a ratio of 10 percent tailings <br /> to 90 percent ore, based on the production of tailings and similar to existing field conditions. <br />