A public comment period continues for air permit revisions requested by operators of the Eagle Mine in Marquette County.
Owners want to install and operate a paste backfill process and to increase the ore trucking limit in their existing permit.
Paste backfill is a method of disposing tailings back into the mine cavity. It involves mixing the tailings with a binder, such as cement. The resulting slurry is then pumped back into sections of the mine that are no longer being used. It helps stabilize the mine structure to prevent sinkholes and cave-ins, and also minimizes the amount of mine waste that’s stored on the surface. It is a more expensive process than other backfill methods.
An air permit is required before any of those changes can be made. A permit limits the release of air pollutants and ensures the request will meet air quality standards, and defines the methods needed to meet the standards.
The public comment period continues until March 17th. You’ll find more information about the request here.
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