Noble gases identify the mechanisms of fugitive gas contamination in drinking-water wells overlying the Marcellus and Barnett Shales
Data appears to rule out gas contamination by upward migration from depth through overlying geological strata triggered by horizontal drilling or hydraulic fracturing. By Thomas H. Darrah, Avner Vengosh, Robert B. Jackson, Nathaniel R. Warner and Robert J. Poreda published in the Proceedings of National Academy of Sciences, August 2014.
Assessment and risk analysis of casing and cement impairment in oil and gas wells in Pennsylvania, 2000–2012
"The identification of mechanisms through which methane may migrate to the atmosphere as fugitive emissions is important to understand the climate dimensions of oil and gas development." By Anthony R. Ingraffeaa, Martin T. Wells, Renee L. Santoro, and Seth B. C. Shonkoff, published in the Proceedings of the National Academy of Sciences, May 30, 2014.
Towards a Road Map for Mitigating the Rates and Occurrences of Long-Term Wellbore Leakage
By Maurice B. Dusseault, Richard E. Jackson, Daniel Macdonald. Published by the University of Waterloo and Geofirma Engineering, LTD., May 22, 2014.
Oil and gas wells and their integrity: Implications for shale and unconventional resource exploitation
The percentage of wells with barrier element failure is between 1.9% and 75%. By Richard J. Davies, Sam Almond, Robert S. Ward, Robert B. Jackson, Charlotte Adams, Fred Worrall, Liam G. Herringshaw, Jon G. Gluyas, Mark A. Whitehead in
ScienceDirect, March 1, 2014.
The Latest Evidence on Leaky Wells
A presentation by A.R. Ingraffea Ph.D, P.E.; M.T. Wells, Ph.D, Cornell University; R. Santoro, R. Shonkoff, Ph.D, Physicians, Scientists and Engineers for Healthy Energy, Inc. November 21, 2013. (Video: 2:33:00)