Arch Coal is laying off 500 miners in Eastern Kentucky by mid-August.
On it's website, Arch Coal describes itself as "one of the world's top frive coal producers."
Layoff notices sent to the state cite a decline in demand for coal.
Layoffs will occur in stages with a August 20th deadline.
Laid-off miners can apply for vacant positons within Arch but the company says there's no guarantee workers will be rehired.