2012-02-28_REVISION - M1980244 (82)

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Strip Pregnant Tank 20,000 Strip Barren Tank 20,000 Strip Intermediate Tanks 20,000 20,000 Pre - treatment Tank 4,500 4.3.1.2 Spill Prevention, Control, and Countermeasures for Process Reagents VLF — Dilute cyanide leach solution (typically 0.01 % to 0.02% or 100 — 200 ppm) is directed to and from the VLF through an HDPE /steel piping system. Pregnant lines are steel and barren lines are steel /HDPE. The pipelines are also equipped with an automatic shut -off, triggered by flow or pressure differentials. In the unlikely event that solution drains or sprays off liner, spill response procedures described in section 5.2.3 of this SRP /SPCC should be followed expeditiously. Pipes, drip lines, and conveyances that direct cyanide solution to and from the VLF are generally installed 15 feet between the conveyance and the edge of the liner. CC &V may also affix pieces of synthetic liner on the side of flanges and valves facing the edge of the liner to reduce the chance of off-pad spraying should a leak develop. Sodium Cyanide Briquettes - Solid briquettes of NaCN contained in vendor - provided lso-Container trailers are stored west of the ADR Plant in a lined, fenced area that drains north to the adjacent VLF. These trailers are transported by tractor truck to the mixing area located on the southwest side of the ADR facility.. During ADR operations, releases from the stored NaCN flow bins would remain on the VLF liner and migrate north toward the main liner system as the cyanide dissolved. The Iso Container trailers are returned to the vendor. The trailers are visually inspected to ensure all NaCN is dissolved and removed from the container prior to returning, . Bulk Cyanide Delivery Cyanide briquettes are delivered in lso-Container trailers for mixing. The transporter will park the trailer in the unlading area for on demand mixing. . Sodium Hydroxide - NaOH liquid is stored directly west of the ADR Plant in a 20,000 - gallon tank within concrete secondary containment and within the tertiary containment of the lined area of the VLF. The concrete containment sump is equipped with a float- activated pump that would return fluid to the plant circuit in the event of a release. A release outside the concrete containment would remain on the VLF liner and migrate north toward the main liner system. Hydrochloric Acid - HCI liquid is stored directly west of the ADR Plant in an 8,200 - gallon, double - walled tank within concrete containment and within the lined area. Releases outside the tank containment would flow north, completely contained within the liner. Antiscalant - Antiscalant liquid is not a hazardous chemical. It is stored outside the ADR Plant in a 4,000 - gallon capacity single - walled, foam - insulated tank on the concrete floor. The ADR Plant is located on liner that drains to the VLF. Antiscalant is also stored within the VLF in insulated tanks. Release of Antiscalant should be controlled, even though the residue is not hazardous. Complete removal of impacted soils is not required. Contaminated soils may be placed on the VLF if desired. Secondary and Tertiary Containment at the ADR Facility - Several redundant containment features exist at the ADR including: (1) liner extends under the building itself forming a continuous barrier to guard against spills reaching the ground water; (2) the ADR building has a concrete floor and curbing that provides secondary containment for spills from reagent tanks; and (3) some of the tanks are double walled construction. 4.4 Spent Carbon, Refinery Slag, and Used Furnace Crucibles Spent carbon fines and used refinery furnace crucibles are generated from gold beneficiation and refining processes. These items are shipped off site for further gold recovery. Spill Response Plan EMS: AGANA/CCV G:\EMS\Plans\Emergency Response Plans \SRP Plan \SRP Ptan.doc Printed Copies are Uncontrolled August 17, 2010 Doc. # E -006 Revision 05 29