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include, and require, reduction of material sizes from solid rock by initial blasting <br /> followed by additional mechanical size reduction to allow sorting, sampling, and <br /> production testing f materials. The mechanical reduction area might be located <br /> underground or possibly above-ground. If the size reduction takes place on the surface, <br /> the location will likely be either immediately west of the adit, or in the area labeled <br /> Reduction/Doghouse as shown on Exhibit Map E. Equipment required will be chosen <br /> once more is known about the properties of the materials that will require size <br /> reduction." In 2015, at the time the permit was approved, the above description was <br /> deemed by DRMS to be sufficient, and correctly described the plan that was being <br /> followed by the operator during the summer of 2020. Per the orders of the CMLRB, the <br /> description of the test milling, and possible production milling is expanded as follows: <br /> Exploration of the subsurface continues and as material that is potentially valuable is <br /> encountered, it is first tested using laboratory sized equipment and then further tested <br /> using pilot sized milling equipment. The rock is reduced in size in a small crushing <br /> plant currently located on the waste rock pile as shown on the map. Since the equipment <br /> is portable, it might remain at that location, or might be moved elsewhere within the <br /> disturbed area to make room for other work. It is also possible that the equipment might <br /> be moved underground. The grinding and mineral recovery equipment is located in an <br /> underground room to keep it out of the weather and also to keep it away from freezing <br /> conditions, thus requiring less energy needs and putting less stress on our fragile <br /> environment. The equipment located in the milling room area is used to test the amount <br /> of target product contained in the mined rock and how much of that can be successfully <br /> collected. Any finished product produced will be stored in the mill room, in the <br /> warehouse or at another suitable location in shelter and protected from weather. <br /> In July 2020, the test equipment was locked out of operation. Its layout is described as <br /> follows, and a typical example flow sheet is attached to assist those unfamiliar with this <br /> type of process. At this site, the rock from the mine is crushed and then returned back <br /> underground to the mill room where it is fed through a ball mill to make it finer. The <br /> output from the ball mill is sent to gravity collection equipment, and then reground and <br /> sent through a flotation process, where a small amount of xanthate and other reagents are <br /> added to collect the gold, allowing it to be separated from the ground rock. As is <br /> commonly known and has been practiced in this industry in Colorado for over 100 years, <br /> xanthate works by binding to the gold concentrate and both the gold and xanthate are <br /> collected with the gold concentrate. If the process is performed correctly, only very low <br /> concentrations of xanthate remain in the product that exits the process (tailings sand). <br /> 5 <br />