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<br /> <br /> <br />(7) Please describe how BMG believes the reported release <br />of cyanide from the flo-bin storage area occurred. Is there <br />a flaw in the design of the flo-bin or in current <br />housekeeping methods? Is there an additional apparatus <br />available which could preclude the loss of cyanide to the <br />environment? <br />The release of cyanide from the storage area occurred as a <br />direct result of the area being inundated with mud and water <br />from the hillside slough. The potential for a release <br />outside of the storage area of this type occurring again has <br />been eliminated by moving the area away from the hillside <br />and providing for internal drainage of the storage area to <br />the leach circuit sump. <br />The presence of cyanide in the storage area which was <br />released from the area during the inundation could have been <br />from dust on the outside of the bins or from a partially <br />open gate which allowed water inside of an empty bin. As <br />described in items 2 and 3, by the design of the new storage <br />area, securing and locking the gates, rinsing the empty <br />bins, visual inspections, care during transport, and <br />training, BMG believes that the potential for future <br />releases has been minimized to the extent possible. <br />(8) BMG reported that it pumped 2500 gallons of <br />contaminated water to the leach circuit and treated the <br />affected area with sodium hypochlorite to neutralize any <br />remaining cyanide. BMG also stated that "the mud was <br />scraped from the area and placed in the tailings pond." <br />What steps did BMG take to determine whether the yard <br />surfacing or subgrade materials in the affected area had <br />been contaminated? If any subgrade materials sampling was <br />completed, what were the results? Was any subgrade soil <br />clean up completed? <br />The standing water was pumped from the area to the leach <br />circuit. The mud was removed down through the layer of <br />wetness and placed in the tailings pond. Then, the area was <br />treated with sodium hypochlorite to neutralize any remaining <br />cyanide. A soil sample was collected from the northwest <br />corner just outside the storage area at a depth of 6 inches. <br />This location was chosen since it was the area of the <br />greatest amount of ponded water. The sample was taken by <br />Alana Scott and analyzed for WAD cyanide at BMG's on-site <br />laboratory. The results indicated less than 0.5 ppm CN. <br />Additional sampling occurred on September 16, 1992 around <br />the perimeter of the storage area at a depth of <br />approximately one foot. These samples were taken by A1ana <br />Scott and are being analyzed by BMG's lab. Results will be <br />available the week of September 21 and will be forwarded to <br />the Division when available. <br />