Laserfiche WebLink
SQUAW GULCH VALLEY LEACH <br />FACILITY AND ADR PROCESS <br />DESCRIPTION & DESIGN BASIS <br />1/25/2012 <br />Page 3 of 3 <br />containers. The container is positioned on a double contained unloading area and a basic water <br />solution is pumped through the containers to dissolve the briquettes. The dissolved solution is <br />stored in tanks (approximately 25,000 gallons each) in a secondary containment area for use in <br />the SGADR processes. <br />Caustic Solution System <br />Sodium Hydroxide is used in the SGADR to raise the pH of the barren solutions. This is required <br />to prevent the formation of hydrogen cyanide gas. The sodium hydroxide will be delivered by <br />tanker trucks and will be stored in a tank (approximately 20,000 gallons) within a double <br />contained area. <br />Hydrochloric Acid System <br />The pregnant solution at this site causes potential scaling to occur on the activated carbon. To <br />manage this scale, the carbon is occasionally washed with a dilute acid solution in the Carbon <br />Acid Wash System. Hydrochloric acid is used for this process. The acid is delivered by tanker <br />trucks to the SGADR. It is stored in a separate double containment area in an FRP storage tank <br />(approximately 10,000 gallons). The tank is equipped with an acid scrubber to remove any acid <br />vapor that would be released during filling or tank expansion due to high ambient <br />temperatures. <br />