Impending Risk of Orphaning: The number and status of onshore U.S. oil and gas wells

When trying to describe the scale of the risk of wells being orphaned to state authorities for final decommissioning with public funds, people often cite a range of numbers from under a million to over 5 million based on diverse meaning and sources. This paper undertakes a comprehensive and systematic review of documented and indicated wells drilled onshore in the U.S. to create a clearer and more authoritative explanation of the number of wells and their status.