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<br />Cripple Creek & Victor Gold Mining Company Exhibit D Cresson Project Amendment 13 22 <br />6 PRECIOUS METALS RECOVERY FACILITY <br />The existing precious metals recovery facilities include the Arequa Gulch Absorption, Desorption and Recovery (ADR1), the Squaw Gulch ADR (ADR2) and the refinery, which is included in the ADR1 complex. ADR1 is located on the south side of the VLF1. ADR2 was constructed pursuant to Amendment 10 to provide gold recovery from pregnant solution from the VLF2. No change to either facility is anticipated as part of this Amendment 13. Pregnant solution generated as part of VLF2 Phase 3 will be pumped to ADR2 for recovery. Both facilities are shown on Drawing C-2. <br />6.1 Chemical Usage at ADRs <br />The same chemicals currently permitted for use will be used in the ADRs as part of this Amendment 13 and are described below. <br />Activated carbon is used in the adsorption process to pull gold from solution and reactivated, as needed, by burning at high temperatures using the reactivation kiln. The activated carbon is be shipped in bags and stored outside of each ADR building. <br />Hydrochloric acid is used in a dilute form to remove scale that builds up on the carbon from the pregnant solutions and is disposed by neutralizing with sodium hydroxide and adding to the makeup water for the barren solution. Acid is delivered by tanker trucks to each ADR and is stored in a fiberglass reinforced plastic mixing tank located within concrete containment. Acid tanks are equipped with an acid scrubber to remove acid vapor that would be released during filling or tank expansion due to high ambient temperatures. <br />Sodium hydroxide is used to neutralize hydrochloric acid solution prior to reuse of the water for makeup water and is used to maintain the pH levels above 10 during carbon stripping. Sodium hydroxide is delivered by tanker trucks and stored within concrete containment area in a tank of approximately 20,000 gallons. <br />Sodium cyanide is used in a dilute solution to pull gold from the carbon during carbon stripping and is added to barren solution to dissolve gold during heap leach operations. Once the gold is removed by electro-winning, the dilute sodium cyanide solution is recycled as barren solution. Sodium cyanide is delivered in liquid form by truck to the site in USDOT-approved containers. The containers are positioned on an unloading area which is surrounded by a concrete containment berm and is adjacent to the ADR buildings within lined areas. The solution is transferred from the containers into storage tanks that are within the containment.