Antiquated regulations originally designed for conventional oil and gas operations need to be redesigned for the newer era of unconventional shale, according to a report released today by the University of Texas, Austin.
The report finds that there are relatively few baseline measurements of water quality in an aquifer before drilling begins to draw on for scientific analysis.
"Some states have revised regulations specifically for shale gas development; regulatory gaps remain in many states, including the areas of well casing and cementing, water withdrawal and usage, and waste storage and disposal," states the report.
It also finds that hydraulic fracturing, or "fracking," a technique used to extract natural gas, is not directly responsible for contaminating groundwater with chemicals or methane.
Instead, the scientists laid the blame on accidents connected to gas development that are on the surface or just below, closer to water aquifers. These could include other aspects of drilling such as improper casing and cementings of well bores, spills of produced water, improper disposal and subsurface blowouts.
Their report echoes previous findings regarding groundwater contamination and natural gas extraction.
"The immediate concern with shale gas development and hydraulic fracturing was that fracking was several thousand feet below the surface," Charles Groat at the university's Energy Institute said in a video report. "We put chemicals in the groundwater that people drank that would be bad for your health. So people are very much opposed to hydraulic fracturing from that point of view."
But fracturing itself -- a process in which water, sand and chemicals are shot at shale at high pressures underground to cause fractures and release natural gas -- does not lead to contamination of aquifers, said Groat. It takes place at about 8,000 feet below ground level, which is thousands of feet below typical municipal water aquifers.
"That doesn't mean there aren't ways for fracturing fluids or flowback waters to get into groundwater supplies, and that brings us closer to the surface than where hydraulic fracturing takes place," said Groat.
He acknowledged that for the layperson, fracturing can encompass all the activities related to natural gas development, not just the drilling process below ground. But it is important to make the distinction so regulators can focus on which part of the extraction process actually leads to contamination, he said.
The problem is the industry is moving at such a fast pace that it is difficult for science to keep up, he said. He then added that, on the positive side, the techniques of drilling also improve each day.
The study was funded entirely by the University of Texas. The researchers had initially sought industry funding but were unable to secure support due to demands industry made over the timeline and method of completion.
The report includes 450 pages of white papers from various experts and examines instances of contamination recorded in the Barnett, Marcellus and Haynesville shales. Its research agenda was designed in cooperation with the Environmental Defense Fund and Syracuse University. It is meant as a systematic review of existing scientific literature, though it is not peer reviewed.
The study finds that in most places in America, no one keeps track of chemicals in groundwater before oil and gas drilling begins, making it difficult to get a read on how gas production changes the water.
It also finds that regulators ought to use more careful methods for analyzing and sampling water. A lack of scientific rigor can affect regulators' ability to attribute pollution to specific causes.
Gas drilling is mostly regulated at the state level, and while some states are on track to developing regulations tailored to the industry, some are lax, according to the report.
Among some of its specific recommendations:
- "States not having regulations for blasting in environmentally sensitive areas or for shot hole plugging during the shale gas exploration phase may want to consider adding these requirements."
- "States may also need to more uniformly require a plan for disposal of wastes (including drilling fluids, drill cuttings, and flowback and produced water) and to ensure that the methods of disposal (e.g., centralized facility, surface discharge with permit, discharge to POTW or injection well, land application) conforms with regulations and best practices."
- "States may need to update or put in place adequate regulations for disposal of wastes containing naturally-occurring radioactive material (NORM) -- as for oil and gas operations in general."
The report also calls for greater enforcement of the regulations: "Evaluation of state enforcement is hindered by several factors, including differing methods of collecting, organizing, and recording violations and enforcement actions; variances in the completeness of records; and responsiveness of agencies to information requests."
The report also finds that methane in water wells in some shale gas areas such as the Marcellus can "most likely be linked to natural sources and likely was present before the onset of shale gas operations."
Fears surrounding methane contamination were first highlighted to a national audience by the documentary "Gasland," which showed a homeowner's tap water catching on fire because of the presence of methane.
Subsequently, a study by Duke University researchers in the journal Proceedings of the National Academy of Sciences found that drinking water near Marcellus Shale gas wells was more likely to be contaminated with methane. People interpreted the study as evidence that the technique of hydraulic fracturing caused the contamination.
But scientists disputed this interpretation, saying the contamination was more likely the result of leaky gas well casings from three nearby wells rather than fracturing. They also pointed out that the study did not have data on the composition of groundwater in these wells before drilling began to get a comparison.
No one has so far studied the health effects of sustained exposure to low levels of methane.
Reporter Mike Soraghan contributed.
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