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Background - Mercury Legislation <br />On February 17, 2011, the U.S. Environmental Protection Agency (EPA) promulgated National <br />Emissions Standards for Hazardous Air Pollutants for gold ore processing and production facilities. <br />Under the final regulation mercury is the only constituent that is regulated. <br />The Clean Air Act of 1990 requires the EPA to establish standards known as Maximum Achievable <br />Control Technology (MACT) for sources of seven air toxics known as persistent, bioaccumulative <br />pollutants, including mercury. The Clean Air Act requires the EPA to; develop regulations for, the sources <br />of the air emissions of seven pollutants known as persistent, bioaccumulative pollutants. <br />The Mercury Export Ban Act of 2008 (MEBA), prohibits the export of elemental mercury from the <br />United States commencing in 2013. Through the MEBA the Department of Energy (DOE) has been <br />tasked with constructing a long term storage facility for elemental mercury waste. The MEBA allows for <br />storage at licensed hazardous waste Treatment, Storage, and Disposal Facilities (TSDFs). The MEBA also <br />requires mercury being sent to the DOE facility for long term storage, have a purity of higher than 99.5%. <br />The DOE is in the process of securing funding to construct the long term storage facility with <br />construction expected to be completed within the next 5 years. Should the DOE long term storage facility <br />not be constructed by this time, it is legislated that the DOE must reimburse the cost of on-site storage to <br />mercury generating sites. <br />Retort Summary <br />Retorts are common place in many industries from; mining, chemical manufacturing, waste treatment and <br />the food production industry. A retort is an airtight vessel in which substances are heated, thus producing <br />gaseous products to be condensed, and captured in a collection vessel. In a chemistry laboratory, a retort <br />is a glassware device used for distillation or dry distillation of substances. It consists of a spherical vessel <br />with a long downward -pointing neck. The liquid to be distilled is placed in the vessel and heated. The <br />neck acts as a condenser, allowing the vapors to condense and flow along the neck to a collection vessel <br />placed underneath. <br />Modifications to the Approved Mine Plan <br />Electric Retort <br />The mercury retort will be operated in a batch process. Gold concentrate from the electrowinning cells <br />will be placed in two trays and loaded into the retort each holding approximately 3 cubic feet. of <br />concentrate. Once loaded, the front hatch of the retort will be closed creating a near air tight seal. Upon <br />closing, vacuum pumps will draw air through the carbon columns, aftercooler, collector, condenser, and <br />the retort. Figure 1 below provides an illustration of the exhaust gas flow. <br />CC&V intends to locate the mercury retort near the furnace inside the refinery located at AGADR. The <br />unit is a 6 cubic feet electric retort, manufactured by Lochhead-Haggerty and the control system consists <br />of six major components; <br />Retort <br />Two condenser tubes (water cooled heat exchangers) <br />Collector <br />Aftercooler <br />Two carbon columns; and <br />Chiller