Miners at Arch Coal's Dal-Tex mine in Logan County began receiving layoff notices Saturday, three days after a federal judge in Charleston barred expansion of the mine pending a September trial.
Arch spokesman David Todd confirmed layoffs had begun, but declined Saturday to elaborate on the extent of the job loss.
More than 300 workers are employed at the Dal-Tex mountaintop removal complex.
The mine is at the center of the controversy over mountaintop removal strip mining, a method in which mountaintops and ridges are sheared away, revealing the coal inside. Excess dirt and rock is then dumped into nearby valleys.
U.S. District Judge Charles Haden issued a preliminary injunction on Wednesday halting new permits for the mine following environmental groups' contentions that the form of mining causes irreversible damage to the environment.
"In the best case, the timing of the permit delays will require substantial and extended layoffs this year," Arch Coal CEO Steven Leer said Thursday in a prepared statement.
Miners calling the Sunday Gazette-Mail on Saturday said dozens of their co-workers had received layoff notices.
Todd said he wouldn't release layoff figures to the public until he was sure that all affected miners had been notified.
Arch Coal lawyers have appealed Haden's ruling to the 4th U.S. Circuit Court of Appeals.