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Climax Molybdenum Company <br /> Permit No.1977-342 Technical Revision (TR-35) <br /> 2.3 Reagents <br /> Water treatment chemicals or reagents are identified in the EPP. Reagents used in the WTP process include <br /> hydrated lime for metals precipitation, polymer flocculant to facilitate the settling of precipitated solids, and CO2 to <br /> lower the pH of the treated water to circumneutral prior to discharge. General information for these chemicals <br /> including safety considerations, storage and handling, effectiveness and monitoring activities is provided in the <br /> EPP. Additional specific information relative to the storage and use of these chemicals at the WTP is provided <br /> below. <br /> 2.3.1 Unloading Stations <br /> Access to reagent truck unloading areas at the WTP utilizes the same truck traffic routes as other bulk deliveries <br /> to the Henderson Mill and, as such, do not create any additional risk for chemical release. Further, the WTP area <br /> is contained and drains to the Bear Paw Drainage Pipeline inlet. The Bear Paw pipeline conveys flows to the TSF. <br /> 2.3.2 Lime System <br /> Hydrated lime is used to raise the pH of the water being treated to alkaline conditions, and metals are subsequently <br /> oxidized and precipitated. Contact can cause irritation to eyes, skin, respiratory system, and gastrointestinal tract. <br /> Hydrated lime does not react as violently with water as quicklime but may still release heat upon mixing. Contact <br /> with eyes can cause severe irritation or burning, including permanent damage. <br /> In the presence of acidic conditions such as acid rock drainage or acid mine drainage, hydrated lime reacts as an <br /> acid neutralizer and buffer. It can be used to raise the pH of acidic waters. Should hydrated lime be delivered <br /> directly into a non-process water or a non-acidic water environment, it would cause short-term impacts to aquatic <br /> communities by raising the system pH. Direct long-term impacts would be negligible to non-existent since calcium <br /> hydroxide would neutralize in the natural system and does not bio-accumulate. <br /> The lime system includes the lime silo, lime slurry tank, lime feed pumps, and ancillary support equipment. The <br /> lime silo is approximately 45-ft tall and sized to hold approximately 50 tons of lime. Hydrated lime is transferred <br /> pneumatically to the silo from bulk tanker trucks and the silo will be equipped with a baghouse system to capture <br /> particulate matter. The lime silo will be located on the south side of the WTP building, while the 250 gallon lime <br /> slurry tank and feed pumps will be within the WTP building,with an enclosed screw conveyor to transfer hydrated <br /> lime from the silo to the slurry tank. Within the lime slurry tank, powder lime is combined with raw/fresh water to <br /> obtain the proper slurry concentration for water treatment. Lime feed pumps then pump the lime slurry to the <br /> lime/sludge mix tank for use in the treatment process. Any lime slurry spill will be contained within secondary <br /> containment/sump system of the plant and returned to the plant feed or process tanks. <br /> 2.3.3 Polymer Flocculent <br /> The polymer flocculent(DAF-10 or equivalent)will be used to promote precipitation of metals and improve settling <br /> of sludge in the clarifier. Dry polymer will be mixed with water in the package polymer make-up system in a 100 <br /> gallon mix tank, aged based on polymer product requirements, and delivered to the 140 gallon polymer dosing <br /> tank where it will then be added to the treatment system. The resulting precipitate or sludge is thickened and <br /> removed from the treatment system using a clarifier. Ultimately, waste sludge will be conveyed to the TSF for <br /> disposal. The product does not contain any hazardous components and is non-reactive, non-flammable, and a <br /> slight human health hazard. Eye protection and gloves should be worn when in contact with the product. Avoid <br /> inhalation of vapors or mist. Product produces extremely slippery surfaces when wet. In the environment, DAF- <br /> 10 is stable and non-hazardous. <br /> 2.3.4 Carbon Dioxide <br /> Carbon dioxide (CO2)will be used for effluent neutralization in the Mill WTP. It is an extremely cold liquid and gas <br /> under pressure and may cause frostbite upon skin contact. Eye protection and gloves should be worn when in <br /> contact with the product or product containers. Ingestion is not considered a potential route of exposure. Store in <br /> a cool, well-ventilated place. In the environment, released carbon dioxide will disperse into the atmosphere. Bulk <br /> April 2022 <br />