A bench is created from the removal of overburden material and coal from the surface of the perimeter of a coal seam, and the machines are generally operated from it. Previously augered areas and trench mining can also be used with a highwall miner. When the highwall miner is operated off a bench, a minimum bench width of forty-two feet is required, with fifty-five feet or more being ideal. The highwall miner is capable of mining coal seams from thirty inches to sixteen feet in thickness and depths up to one thousand feet. The highwall miner mines this range of coal seam heights because of its fitting interchangeable cutterhead modules. A highwall miner has low, medium, or high seam mining ability.