title: Effective permeabilities of abandoned oil and gas wells: analysis of data from Pennsylvania.
abstract: Abandoned oil and gas (AOG) wells can provide pathways for subsurface fluid migration, which can lead to groundwater contamination and gas emissions to the atmosphere. Little is known about the millions of AOG wells in the U.S. and abroad. Recently, we acquired data on methane emissions from 42 plugged and unplugged AOG wells in five different counties across western Pennsylvania. We used historical documents to estimate well depths and used these depths with the emissions data to estimate the wells' effective permeabilities, which capture the combined effects of all leakage pathways within and around the wellbores. We find effective permeabilities to range from 10(-6) to 10(2) millidarcies, which are within the range of previous estimates. The effective permeability data presented here provide perspective on older AOG wells and are valuable when considering the leakage potential of AOG wells in a wide range of applications, including geologic storage of carbon dioxide, natural gas storage, and oil and gas development.
authors.affiliation: †Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States.|‡Environmental Earth System Science, Stanford University, Stanford, California 94305-4216, United States.
authors.forename: Mary
authors.initials: M
authors.lastname: Kang
authors.affiliation: †Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States.
authors.forename: Ejeong
authors.initials: E
authors.lastname: Baik
authors.affiliation: †Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States.
authors.forename: Alana R
authors.initials: AR
authors.lastname: Miller
authors.affiliation: †Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States.
authors.forename: Karl W
authors.initials: KW
authors.lastname: Bandilla
authors.affiliation: †Civil and Environmental Engineering, Princeton University, Princeton, New Jersey 08544, United States.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Celia
mesh_terms: D002245:Carbon Dioxide / Q000032:analysis; D060587:Groundwater; D008697:Methane / Q000032:analysis*; D061329:Oil and Gas Fields; D010414:Pennsylvania; D010539:Permeability; D014876:Water Pollution
chemical_list: D002245:Carbon Dioxide; D008697:Methane