Parkway Mine and Preparation Plant Parkway mine is an underground mine located near the city of Central City in Muhlenberg County, Kentucky that extracts steam coal from the West Kentucky #9 coal seam. Armstrong has been producing coal at Parkway since 2009 utilizing continuous mining units employing room-and-pillar mining techniques. Parkway coal is processed on site at the Parkway preparation plant, which has a throughput capacity of 400 tons of raw coal per hour. Parkway sold 1.5 million tons of coal in 2011.