Are the underground storage chambers really safe?
A. The current storage of arsenic trioxide underground at Giant Mine is safe. The underground storage chambers are contained in bedrock and sealed with concrete bulkheads. The pumps at Giant Mine keep the level of groundwater well below the storage chambers. Any water seepage that comes into contact with the storage chambers is collected in the mine water system, pumped to the surface and treated. The mine and local surface waters are regularly monitored to ensure that arsenic trioxide does not escape into the environment. The arsenic trioxide at Giant Mine has been stored safely underground for decades and will continue to be safely stored until the Remediation Plan — and Frozen Block Method — is fully implemented.
