“Water is the one substance from which the earth can conceal nothing; it sucks out its innermost secrets and brings them to our very lips” – Jean Giraudoux
The other month I was invited to an underground citizen group in Greeley, Colorado. I am being literal when I write “underground”, as the meetings are held in neighbors’ basements. Only there in the safety of the basement do people feel comfortable expressing their concerns about pressures from the oil and gas industry to expand hydraulic fracturing within their city limits. Greeley is known as the “donut hole”, a tiny spot among a dense ring of wells that oil and gas companies are hungry to fill.
I asked the person who invited me about the history behind the group and why after all of these years surrounded by the industry it was only now that they were becoming concerned. She responded that their apprehension was fueled by the movie Gasland, which first alerted them to potential dangers associated with hydraulic fracturing.
This certainly was not an atypical response. I have to admit that since sensationalized documentaries rank at the top of my movie watching list, it was one of my first introductions to the industry as well. However, there is much more to the story filmaker Josh Fox presented. He received intense criticism (the most critical from Energy In Depth, for which Fox responded with an Affirming Gasland letter) for his portrayal of contaminated water and human health effects, especially for his depiction of the faucet fires ignited from methane migration in domestic wells. Although measurable methane was present in these wells, had Josh Fox unfairly implicated the oil and gas industry?
Methane is a natural hydrocarbon gas that is produced by bacteria or by geologic processes involving heat and pressure. In certain concentrations, methane can be flammable. There are two types of methane, biogenic and thermogenic. Biogenic is naturally occurring, created by decomposing organic material, while thermogenic is formed by intense pressure in underground rock formations. Typically, thermogenic is found in deeper layers of shale, while biogenic rests in shallower pockets. The type of gas is identified by an isotope test; which is essentially the “fingerprint” of gas. However, the test does not reveal the migratory path, which is important since both forms yield similar effects. It is not only possible for thermogenic methane to migrate into areas usually reserved for biogenic, but further punctures in the earth’s geology can lead to the migration of biogenic methane as well.
The documentary Gasland, profiled four cases of methane migration in domestic drinking wells, one in Dimock, Pennsylvania and three near Fort Lupton, Colorado. Although the film implies that these instances were caused by hydraulic fracturing, oil and gas companies were quick to claim otherwise. Following investigations by the Pennsylvania Department of Environmental Protection (DEP) and the Colorado Oil and Gas Conservation Commission (COGCC), it was determined that the case in Pennsylvania and only one of the three cases in Colorado contained a mixture of biogenic and thermogenic methane. The other two cases, the Markham and McClure wells, were biogenic and not related to oil and gas activity. In addition to the isotope test, the wells were tested for hydrocarbons benzene, toluene, ethylbenzene, and xylenes (BTEX) produced by oil and gas wells. The tests were negative. The following is the famous faucet fire scene from the documentary Gasland.
There have been very few studies about methane migration. One of the first and most notable papers was published in 2011 by Duke University in the Proceedings of the National Academy of Sciences. The scientists collected and analyzed 68 private well samples in the Marcellus shale formation in Pennsylvania and New York. The samples revealed that 85% contained measurable amounts of methane and those levels were on average 17 times higher in wells located within a kilometer of active hydrofracking sites. The study generated the following graph showing methane concentrations in relation to the distance to the nearest gas well.
The isotope analysis was used to fingerprint the origin of the methane, linking it to drilling sites. In an expansion to the study, Duke scientists sampled another 141 wells achieving similar results. This study also found that ethane, a hydrocarbon associated with thermogenic methane, was also present at rates 23 times higher for homes closer to drilling sites. Their conclusion was that these cases were most likely caused by faulty drilling operations and are a minority, rather than an epidemic.
The Marcellus Shale Coalition provided a critical response to the Duke studies, stating that many of the wells had previous issues with methane prior to drilling and without pre and post testing, the presence of thermogenic methane did not confirm a connection to the oil and gas industry. They also argued that most levels were far below the “action level” (shown on the graph above) and noted that ingesting methane (while the thought of it sounds like certain death) is actually not toxic to humans. This may be comforting to some, but I do wonder how many people are content with the knowledge they have the ability to light their tap water on fire. May we expect that residents with methane migration will burst into flames or will they just have really great dinner party entertainment? Based on the highest levels of methane measured from the Duke study and assuming an airtight house (not likely), approximately 0.035% of the air would be composed of methane. This is far below the lower explosive limit of 5% and the asphyxiation limit of 50%. While the risk is certainly elevated, it appears that residents will be safe by the currently accepted measured standards. Nevertheless, they might want to consider buying a methane detector just in case.
Like so many other controversial topics, it is hard to find accurate information about hydraulic fracturing. Participants from both sides of the debate are prone to exaggeration and cherry-picking information. As profrackers make claims that it is safe and there is no risk to public health and the fractivists predict environmental catastrophe, it seems that both sides are doing themselves a disservice by skewing information to fit their respective agendas. Gasland, the COGCC, the Marcellus Shale Coalition have all allowed bias to drive their message. At one time Gasland provided the most damaging information against hydraulic fracturing, but their movement ultimately lost momentum, because of some of the inaccuracies included in the film. The COGCC’s response to the movie was also criticized for cherry picking information as they provided a detailed account of the Markham and McClure wells, while essentially glossing over the proven contamination case in the other well. Meanwhile Cabot Oil and Gas was ordered by the Pennsylvania DEP to supply water to 32 families (including the family profiled in Gasland) in Dimock, Pennsylvania. The reasons behind this order are sealed through nondisclosure agreements. Finally, the Marcellus Shale Coalition argued that the presence of thermogenic methane does not implicate the oil and gas industry in the Duke study. However, the industry bases the absence of thermogenic methane as confirmation that they are not responsible for methane migration. This is a clear contradiction and only damages people’s confidence in the industry.
It seems one of the biggest critiques of the hydraulic fracturing boom is the lack of transparency and denial from both sides of the debate. With an array of conflicting information and nondisclosure agreements, it is not a surprise that many do not feel comfortable accepting the risks associated with hydraulic fracturing. As fracking bans and moratoriums continue to find their way on ballots, maybe it is time that the oil and gas industry improve transparency and accept firmer regulations required by other industrial practices until science can reveal the reality and provide a substantive risk assessment. Because right now, it seems that opposing sides are on a collision course with one side most assuredly going down in flames in the end.