There’s been some recent social media chatter in Australia about the recent work of United States professor Tony Ingraffea.
In the United States, Tony Ingraffea has made a name for himself for making assumptions in regards to methane emissions that have since been disproved.
After putting together a study that claimed natural gas was worse for the environment than coal, many universities and experts began looking into this phenomenon.
Over the next couple of years studies from Carnegie Mellon, Massachusetts Institute of Technology, Department of Energy and even a colleague of Mr. Ingraffea’s from Cornell found his work based in fiction rather than reality.
From there, experts have denounced Ingraffea for using his credentials as a hired gun for those strongly opposed to the development of clean burning natural gas.
“Alas, [the Cornell] analysis is based on extremely weak data, and also has a severe methodological flaw (plus some other questionable decisions), all of which means that his bottom line conclusions shouldn’t carry weight.”- Michael Levi, Council on Foreign Relations, April. 2011
“ [W]hat Ingraffea is doing in continuing to claim that natural gas is as bad as coal is not a matter of looking at the same data as everybody else and drawing different conclusions. It is more a matter of distorting science in order to support a preconceived political agenda.”-Raymond Pierrehumbert University of Chicago, Aug. 2013
“This paper is selective in its use of some very questionable data and too readily ignores or dismisses available data that would change its conclusions.”- Dave McCabe, Clean Air Task Force, Apr. 2011
“There were numerous studies on fugitive emissions of methane. There was a very famous Cornell report which we looked at and decided was not as credible as…well we didn’t think it was credible, I’ll just put it that way and it was over estimating fugitive emissions.” – former President Obama Energy Secretary and Nobel Prize-winning physicist Steven Chu
This time around, Ingraffea’s study uses many of his same tactics by using selective data points to garner sensational headlines like the one being touted by the Lock the Gate movement.
However, once again, the truth is far different than what is being touted by Ingraffea.
Ingraffea is no stranger to manufacturing commentary regarding well casing failure rates regarding onshore development of natural gas.
He is quite fond of claiming “half of all shale wells leak” and bases his claims on a decade old paper in Oilfield Review.
There are three good reasons to question the veracity of his claims about well leakage:
- Firstly, the paper he is referencing had nothing to do with onshore oil and gas development. It only looked at offshore development in the Gulf of Mexico. These are two very different scenarios
- Secondly, the detection of something called sustained casing pressure (SCP) is not a sign of well failure or an actual leak
- Thirdly, he ignores the fact that well casing practices and technology are far more advanced than just 5 years ago.
In rare cases, sustained casing pressure or the buildup of pressure in a well may lead to a crack in a layer of casing. However, given the fact that Australian operators are required to utilise multiple layers of cement and steel casing, this is not a reason for concern.
For a well to actually leak all of these layers would have to be compromised, which is extremely uncommon.
As petroleum engineer George E. King explained at an International Society of Petroleum Engineers presentation,
“[A]ctual well integrity failures are very rare. Well integrity failure is where all barriers fail and a leak is possible. True well integrity failure rates are two to three orders of magnitude lower than single barrier failure rates.”
This Ingraffea study, much like his assumption a couple of years ago, are both based on this premise that surface casing pressure and a leaking well are the same exact thing.
In his study, he states,
“A leaking well, in this context, is one in which zonal isolation along the wellbore is compromised due to a structural integrity failure of one or more of the cement and/or casing barriers.” (p. 1).
That statement to someone familiar with the industry is a red herring. Unfortunately the public in general would quickly gloss over it without batting an eye.
In Canada, British Columbia Oil and Gas Commission spokesman Hardy Friederich explained that while 10 percent of wells in British Columbia have experienced pressure or some kind of leakage between the barriers inside the well,
“This gas does not migrate to soil or water — it is trapped within the surface casing protection layer. From there it has to be vented to ensure it is safely disposed.”
While industry and regulators acknowledge the fact that surface casing pressures exists and is remediated when needed, it does not mean there is an actual increase in well casing failure rate.
But that doesn’t stop Mr. Ingraffea from making even more precarious assumptions to elevate his already grandiose claims.
To increase the rate of a wells failure rate in his modeling, Mr. Ingraffea relies on “findings” like the ones below:
- “[V]iolation codes are sometimes entered incorrectly as non-cementing/casing issues and later corrected in violation comments.” (p. 2)
- “[W]ells drilled during boom periods may be more susceptible to loss of zonal isolation because operators might cut corners in an attempt to increase the number of wells drilled over a short period of time.” (p. 2)
- “This suggests that the majority of these active, older wells are no longer being inspected.” (p. 4)
Actual research into well casing failure rates tells a much different story.
In the United States, the Ground Water Protection Council, a group of state regulators whose mission is “to mutually work toward the protection of the nation’s ground water supplies”, found wells casing failure rates to be minuscule.
Their 2011 study looked at more than 34,000 wells in Ohio from 1983 to 2007 and more than 187,000 wells in Texas between 1993 and 2008. The study found a well failure rate of 0.03 percent in Ohio and only about 0.01 percent in Texas.
Since that study, oil and gas producing states across the United States have all updated their well casing programs to increase safeguards for their aquifers.
This latest report is just another attempt to cloud the facts regarding the safe and responsible development of natural gas.