Underground Coal Mining
Underground mining involves opening one or more portals or shafts into the earth that follow or intercept coal seams that are too deep for surface mining methods. Two main methods of underground mining are practiced in Pennsylvania:
Room-and-Pillar: Generally used for seams that are relatively flat or gently dipping. As the 'room' is mined, large 'pillars' of coal are left behind to support the weight of the overburden and rock layers above. This type of mining is the traditional method of underground mining used in Pennsylvania and can result in as much as 75% recovery of the target coal seam.
Longwall Mining: A mechanized coal shearer is mounted between a conveyer system and a series of self-advancing hydraulic roof supports. This machine moves along the panel of coal to lengths of 820 feet and is almost completely automated. As the coal is removed and transported away via the conveyer, the roof supports are removed and allowing the roof to collapse into the void. This method of mining can result in seam extraction of greater than 90% but may cause surface subsidence features.
The following Chapters of the Pennsylvania Code (Title 25) provide the regulatory basis for surface coal mining and reclamation in Pennsylvania:
86: Surface and Underground Coal Mining: General
88: Anthracite Coal
89: Underground Mining of Coal and Coal Preparation Facilities
A permit is required to conduct underground mining activities. Underground mining activity includes the surface operations incidental to the underground area of extraction. The permit area includes support areas, facilities and roads. Permits are also required for underground exploration activities and processing plants. A coal mining permit must be renewed every five years. An operator of a coal mining permit must be licensed. The area covered under a coal mining permit must be bonded to ensure reclamation is completed. Permit application documents, additional forms, informational publications and Technical Guidance documents can be found in the Department's eLibrary.
Underground bituminous coal mining (which includes all longwall mining) is permitted by the California District Mining Office located in Coal Center, Pennsylvania. Anthracite underground mines (no longwall mines) are permitted by the Pottsville District Mining Office.
Public Notification: Coal Mining Permits
Citizens Guide to Permits (PDF)
Effects of Underground Mining
Act 54 Reports are conducted in 5 year increments to document the effects of underground mining in the state.
Surface Subsidence Agent Program
Methane Gas in Water Wells (PDF)
Stray Carbon Dioxide in Homes (PDF)
Surface Owner Rights and Responsibilities Summary (PDF)
Water Supply Replacement and Subsidence Damage Repair – Underground Bituminous Coal Mining Operations (PDF)
A Guide to Water Supply Replacement and Subsidence Damage Repair (PDF)