Consol Energy Graysville, Pennsylvania, United States

Using innovation for more efficient mine shaft construction

Enlow Fork Oak Springs Slope drill and blast, mine shaft construction

Drill and blast construction of a new slope, bottom station, and rail turnout

Alberici excavated and constructed a 2,568-foot over/under slope entry at Consol Energy’s Enlow Fork coal mine in western Pennsylvania. Using drill and shoot excavation techniques, Alberici removed 25,900 cubic yards of rock during construction of a new slope that sinks to depths of 651 feet below the earth’s surface at a 14 degree angle.

Enlow Fork Oak Springs Slope entrance, mine shaft construction

Using innovation to improve productivity and drive down costs

To reduce costs and help Consol achieve their production goals, Alberici worked closely with MSHA and the Pennsylvania Department of Environmental Protection to gain approval for the state’s first permissible diesel-powered mucker. Compared to a traditional air mucker, the diesel mucker, a custom retrofitted Caterpillar 953 loader, significantly improved productivity and safety on the project. Use of this safer, more efficient equipment resulted in total cost and schedule savings of approximately 20 percent.

Enlow Fork Oak Springs Slope structural reinforcement, mine shaft construction

Structural reinforcement and shaft lining techniques

The $23 million Oak Springs slope project also included installation of a 75-by-30-foot bottom station with a rail turnout and an 84-foot material transport conveyor. High-strength epoxy bolts, straps, mesh, and shotcrete support the roof and ribs of the new tunnel, while finished concrete floors were placed in the bottom station and throughout the tunnel’s intermediate section.

Enlow Fork Oak Springs Slope pittsburgh, mine shaft construction

Experience in the Pittsburgh Coal Seam

In addition to Enlow Fork, Alberici also performed slope access construction at nearby Bailey Mine. Together, the two mines feed the Bailey preparation plant, which processes 28 million tons of coal annually and is among the largest coal production facilities in the United States. Pittsburgh Coal mined from the seams at Enlow Fork generates more power per pound and leaves less fly ash after burning than any other type of coal.