1. Methane Leakage from Abandoned Oil and Gas Wells Alana Miller ‘15, EJ Baik ‘16, Daniel Ma ‘17 October 3rd, 2014 Summer of Learning Symposium

2. Project Summary ● Methane is a potent greenhouse gas ● A significant amount of methane is leaking from abandoned oil and gas wells ● Our project is to learn more about the methane leakage ● Two field trips to Pennsylvania over the summer

7. Data Analysis Overview ● Determining Methane Concentrations/Calibration ● Flow Calculations ● Statistical Analysis

8. Determining Concentrations/Calibration Flame Ionization Gas Chromatography ● raw data is the peak area for a specific gas (mVolts.min) ● different gases have specific time signatures ● use gas standards to determine the time signature and calibration ratio

9. Flow Calculations dc/dt is slope of concentration vs. time plot Scaled the control flow based on the well chamber area

10. Methane Flows (June 2014)

11. Statistical Analysis

12. Well Drilling History, Pennsylvania Estimate for total wells: 300,000 – 920,000 Arnold R, Kemnitzer WJ (1931) Petroleum in the United States and Possessions. Harper and Brothers, New York and London Commonwealth of Pennsylvania Department of Environmental Resources. (1989). Oil and Gas Developments in Pennsylvania in 1989 (Report No. 203) (J. A. Harper & C. L. Cozart, Authors). Harrisburg, PA.

13. Average Well Depths (PA)

14. Estimate for Total Plugging Cost, PA Factors that influence plugging costs include: –Depth –State/Location –Type (conventional, shale, etc) –Condition and Accessibility –Plug length, Age, Complications, Materials used Well plugging – high correlated with depth Number of wells and average depth by year used Estimate: $1.5 billion Range: $840 million - $2.4 billion Plugging cost of high emitters (16% of wells)- $240 million Andersen, M., & Coupal, R. (2009). Economic Issues and Policies Affecting Reclamation in Wyoming’s Oil and Gas Industry. University of Wyoming. Mitchell, A., & Casman, E. (2011). Economic Incentives and Regulatory Framework for Shale Gas Well Site Reclamation in Pennsylvania. Carnegie Mellon University.

15. Value of Methane from highest-emitting well: $376, $330, and $220 Natural Gas Prices (US)

16. Alternative Energy Credit Prices Kang, M. (2014). Pennsylvania’s Alternative Energy Portfolio Standard: A Review of In-State Trends, Princeton University, Princeton, NJ.

17. Acknowledgments We would like to thank Mary Kang, Cynthia Kanno, Kenny Campbell, David Pal, Matt Reid, Peter Jaffe, Yuheng Chen, Joe Vocaturo, Wangyal Tsering, Ryan Edwards, Michael Celia and Denise Mauzerall for all of their help and guidance in this work