Coal Pillar Study

The Pennsylvania Department of Environmental Protection (DEP) reviewed a study proposing changes to existing requirements for coal mine pillars as well as alternative methods for constructing natural gas wells where coal is mined underground. DEP found that the study did not provide results supporting changes.

Coal mine pillars are columns of coal or rock left in place in the mine to support overlying rock and furnish protection for gas wells drilled in the permitted area of a mine. Currently, the size of pillars suitable for ensuring the integrity of gas wells and miners’ safety is specified by the Joint Coal and Gas Committee report, first published in 1957.

The new industry-agency study, titled the Gas Well Pillar Study Update, is the result of Act 2 of 2011, which called for a review of the 1957 study in light of modern longwall mining methods and their impact on natural gas well development.

• John T. Boyd Company Gas Well Pillar Study Update (see Appendix A for 1957 Coal Pillar Study)(PDF)
• The Pennsylvania Department of Environmental Protection’s Review of the Gas Well Pillar Study Update Completed by the John T. Boyd Company (PDF)