A Libby company has applied with state regulators to significantly expand a rock quarry in Lincoln County.
Noble Excavating, Inc. is seeking state approval to operate a 150-acre granite and gravel mine northeast of Libby.
The mine would operate for an estimated 80 years and produce gravel, asphalt, fill and riprap.
Herb Rolfes with the DEQ environmental management bureau says an environmental assessment of the proposal will be conducted once the application is deemed complete.
Noble employs 65 full-time and seasonal workers, producing up to 100,000 tons of gravel and rock per season.
The company has been operating under a Small Miner Exclusion Statement, which allows up to five acres to be disturbed without a Department of Environmental Quality permit.