2012-10-01_REVISION - M1977306 (22)

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(5) Designated Chemical Evaluation Dewatering operations at the mine result in groundwater that requires treatment before being discharged into the environment. The water treatment chemicals used on site include barium chloride and an anionic flocculant. No more than 100 lbs of barium chloride and 50 lbs of anionic flocculant will be stored on site. Neither of these is a "designated chemical" and therefore will not require additional handling requirements beyond what is recommended in the accompanying Material Safety Data Sheets (MSDS) provided in Appendix II. MSDS sheets for all chemicals are maintained in a binder at the mine site. The water treatment chemicals are designed to remove potentially harmful constituents from the mine discharge water during the water treatment process. Barium chloride is added to the untreated water to precipitate dissolved radium -226. The flocculant is added to assist in the settling process. The barium chloride is mixed into a 3% solution in a 500- gallon tank and then added to the mine water as it is pumped to the treated water ponds located on Monogram Mesa above the mine site. This will generate radium/barium sulfate precipitate that settles in the treated water ponds. Flocculants will be added as needed, particularly in the winter. Flocculants are typically non -toxic chemicals that cause the fine particles in solution to agglomerate into flocs, which settle much more rapidly than would the individual dispersed particles. Flocculants are commonly used in municipal water treatment plants. The chemical precipitate produced from the treatment will settle out in the ponds as sludge. This sludge will contain low levels of radionuclides. Also, the amount of sludge produced is very small, and the ponds may need to be cleaned out prior to the end of mining operations. Post treatment mine water is sampled on a routine basis as required by the CPDS discharge permit regulated by the CDPHE before discharge to the environment. During mining operations, treated water flows by gravity down the hill and discharges to the major drainage near the waste rock pile. Magnesium chloride or a similar non - hazardous chemical may be used to treat haul roads within the mine and the waste pile area as needed. The chemical will be added in a dilute solution to the road surface where it will bind with the road material. The hard surface created by this treatment will minimize the amount of fugitive dust generated by mine haulage activities. Road treatment will be performed by a contractor who will provide the magnesium chloride as well as the equipment to distribute it. No onsite storage will be necessary. Diesel fuel, oils, and antifreeze will be used in the mine equipment. Storage and use of these products is discussed in Rule 8, Materials Containment Plan, and the Drainage Design Plan (Appendix III). O'Connor Design Group Inc. U - 7