A proposed plant that would turn coal into diesel fuel in southwest Indiana has overcome a legal challenge to its air permit.

An administrative law judge ruled Indianas environmental agency broke its own public comment rules when it issued an air pollution permit for a planned $2.5 billion coal-to-diesel plant in Spencer County.

The Indiana Department of Environmental Management will collect written comments and hear public testimony about the draft air permit during a Dec. 5 hearing in Lincoln City.

A planned $2.5 billion diesel fuel facility would be located on a 550-acre site annexed by the town of Dale last year.