124 Fixing the Silent Leak: Identifying, Quantifying, Prioritizing, and Mitigating the Environmental and Health Impacts of Legacy Oil and Gas Drilling in North America

This session invites abstracts applying field studies, laboratory experiments, process-based and machine learning modeling, or multidisciplinary datasets to identify, quantify, and mitigate impacts from oil/gas wells of all types and statuses (active, abandoned, orphaned).

Monday, 20 October 2025
1:30 PM - 5:30 PM
HBGCC, 214A

Testing Methodologies for Locating and Measuring Emissions from Orphaned Oil and Gas Wells in Western Pennsylvania

Paper number: 124-2
Program: Technical Sessions
Time: 2:00 PM – 2:20 PM

Authors

Abstract

There are over 30,000 documented orphan oil and gas wells in Pennsylvania with estimates of an additional 300,000 to 700,000 undocumented wells. Developing methodologies to efficiently and cost effectively locate these wells remains a challenge for oil and gas regulators across the U.S. In collaboration with the Pennsylvania Department of Environmental Protection, the US Department of Energy’s Orphan Well Program, McGill University, and Sawback Technologies, we present the Environmental Defense Fund-led drone and ground geophysical surveys in northwest Pennsylvania designed to test methods to locate undocumented wells and measure their methane emissions. Machine learning algorithms analyzed data from a drone magnetic survey, collected over 8 square miles of mountainous terrain, and yielded 257 target anomalies. ~230 of the sites were accessible by ground truthing field technicians, of which 36 are verified as previously documented well sites, 33 are undocumented wells with above ground features, and 22 likely wells buried beneath a former strip mine. Initial field verification using metal detectors and visual inspection confirmed 35% of predicted locations to be wells (both documented and undocumented), whereas an additional verification survey using ground magnetometers verified 65% of ~50 accessible predicted locations within a strip-mined area to have distinctive signatures of undocumented buried wells. In addition, 30 undocumented wells were verified to match historic well locations on historical US Geological Survey topographic maps. The Environmental Defense Fund will also share insights on the potential for detecting methane emissions from wells using drone-based tunable diode laser absorption spectroscopy, an emerging technology for methane monitoring, and the challenges and successes of a collaborative approach to large scale area identification, and public outreach.

Geological Society of America Abstracts with Programs. Vol. 57, No. 6

doi: 10.1130/abs/2025AM-412926

© Copyright 2025 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.