New Study shows Methane from Fracking Sites can flow to Abandoned Wells

USGS photo/ public domain ~ Fracking site on Marcellus Shale in PA

Last week the University of Vermont released a new study showing that methane from active fracking sites can escape through faults that connect to preexisting, abandoned oils and gas wells. The study, to be published in Water Resources Research on October 20, showed that methane release measured at abandoned wells near fracking sites can be significant but did not investigate how the process occurs.

In August, the EPA proposed measures that would cut methane and VOC emissions from the oil and natural gas industry and clarify permitting requirements. These regulations would help combat climate change, reduce air pollution that harms public health, and clarify Clean Air Act permitting requirements for the oil and natural gas industry, says EPA.

Since then, the industry has been hotly debating the proposed regulations on limiting release of methane during fracking operations. That debate, says James Montague, an environmental engineering doctoral student at the University of Vermont who co-wrote the paper, “needs to take into account the system that fracking operations are frequently part of, which includes a network of abandoned wells that can effectively pipeline methane to the surface.”

The researchers studied an area in New York state underlain by the Marcellus Shale formation, which had been fracked until a ban went into effect in the state in the summer of 2015. They used a mathematical model to predict the likelihood that the hydraulically induced fractures of a randomly placed new well would connect to an existing wellbore, putting that probability between .03 percent and 3 percent.

Since then, industry-sponsored information published vastly increased assumptions about the area impacted by a set of six to eight fracking wells known as a well pad - to two square miles -- increasing the probabilities cited in the paper by a factor of 10 or more.

Not all abandoned wells provide a pathway to surface for methane. But given the large number of abandoned wells, even a small percentage can potentially pose an environmental risk. You can read their abstract here.

Methane Leaks Higher than Previous Estimates

Part of compressor station in Bradford County, PA

A new study finds that methane leaks from the production and transportation of gas could be 50 percent higher than EPA estimates. It also warns that switching vehicles from traditional gasoline and diesel to natural gas will do nothing to slow climate change.

“Methane Leaks from North American Natural Gas Systems” is a policy paper - a collaborative effort by sixteen academics who reviewed and synthesized data from 200 papers published in the past two decades.

The lead author is Adam Brandt, an assistant professor of energy resources engineering at Stanford University. In comments to the press, he explained that official agencies such as the EPA are underestimating leakage of natural gas into the atmosphere. Brandt reminded people that leaked methane is a greenhouse gas, just like carbon dioxide, but 30 times more potent. He also noted that although converting fleets from diesel to natural gas sounds like a good idea – burning gas puts less carbon into the atmosphere than burning diesel – any potential climate benefits would be negated by the leaked emissions from gas drilling and production.

Those gas leaks come from emissions at well pads, storage tanks, old and abandoned wells, abandoned infrastructure, and holes in pipelines. Brandt estimates there are at least 400,000 gas wells – a low estimate given that the US Energy Information Administration tallied up more than 510,000 back in 2010. As for pipelines, “there are millions of miles,” he said in a video press release last week. Brandt characterizes gas as “abundant, cheap and domestic” and seems to approve of using it to replace coal in power production. But the gas industry needs to plug the leaks. It’s in the industry’s best interest, he says. Those emissions represent lost money and if the country hopes to use gas as a fuel “then we need to get leakage under control.”

Tony Ingraffea agrees that there is more methane escaping into the atmosphere than is accounted for by EPA studies. But he criticizes Brandt et al for not going far enough in their review. Ingraffea, a professor at Cornell’s School of Civil and Environmental Engineering, co-authored an earlier study warning that extracting natural gas could do more to aggravate global warming than mining coal.

The problem with Brandt’s study, says Ingraffea, is that it ignores some important data. In particular, the authors eliminated data that seemed “too high” – even though they were actual measurements. Several recent studies have used airplanes and towers to measure methane in the air and found emissions to be much higher than EPA estimates, with some as much as 75 percent higher.

Brandt and his colleagues determined that those measurements were too high, or came from production areas that weren’t representative of the country as a whole, so they dismissed the data. But you don’t get to toss out data you don’t like unless you have very good reason, says Ingraffea.

Another problem, says Ingraffea,  is that the authors simply assert that the 3 million or so abandoned oil and gas wells scattered across the nation are properly plugged and therefore probably not leaking. “The problem with that,” he says, “is that they don’t know where all those abandoned wells are, so they can’t really measure whether they’re leaking or not.”

Ingraffea also takes issue with the study’s claim that, if industry could plug up the leaks, burning gas in power plants would be better for the climate instead of burning coal. In order to make that claim they stretch out their timeframe to 100 years.

“That’s totally arbitrary,” says Ingraffea, “and not based on science.” The Intergovernmental Panel on Climate Change (IPCC) gives us about 20 to 30 years before we approach a tipping point, Ingraffea explains. “We can’t wait that long to start decreasing the carbon emissions from fossil fuel.” He adds that using a hundred-year timeframe is a policy decision that is “…perhaps based on faulty scientific understanding of the climate change situation in which we find ourselves or perhaps political wishful thinking.”

Now is a good time to be reexamining and summarizing previous studies, says Ingraffea. But it’s premature to draw conclusions, because every year there are new studies by scientists collecting actual measurements in the air and on the ground. And the data from these new studies continue to show methane emissions at rates much higher than previously thought.

Looking at the big picture, Ingraffea believes the study asks the wrong question. Instead of trying to pin down an average emission rate of methane, they should be asking how much risk we are willing to take. “Risk is the key issue of any policy decision,” says Ingraffea. Sometimes there are bad things that can happen, but they have little consequence so we live with them – even if they happen frequently.

“But this is one thing with a major consequence, so we have to be conservative in our risk taking,” says Ingraffea. Using the average value of methane emissions is inadequate, he says. Policy makers need to peg emission allowances closer to the lower end – and even then acknowledge the uncertainties surrounding that level.

“In the meantime, many of those crucial next 20 years are going by,” Ingraffea warns, “and we should have already started to reduce all fossil fuel use, not increase it as this study proposes.” 

This article first published in Tompkins Weekly, February 24, 2014.

Fracking's Contribution to Greenhouse Gases Worse than Estimated

The argument for burning gas instead of coal goes something like this: burning gas is “cleaner” because it emits less carbon dioxide than oil or coal – even though methane is a much more potent greenhouse gas.

So if you can keep the gas you drill from escaping before it is burned as fuel, you might have an advantage. The problem is that gas escapes – from wells, pipelines, compressors. A couple years ago the federal Environmental Protection Agency had estimated that 0.8 percent to 1.6 percent of natural gas production escapes, on a national average.

Then last year the Environmental Defense Fund (EDF) published a paper finding that as long as escaping methane was less than 3.2 percent of lifetime production, natural gas would be better than coal for electrical production.  According to EDF, 3.2 percent is the “threshold”;  methane emissions above that level would eliminate the justification for using gas as a “transition fuel” to replace coal for electricity generation.

Now, new research shows that more – much more – methane is escaping from gas production than thought. Studies by the National Oceanic and Atmospheric Administration (NOAA) in Utah’s Uintah Basin showed that up to 12 percent of the gas produced could be going into the atmosphere instead of the pipeline. The basin serves about 6,000 wells and accounts for about one percent of the nation’s gas production.

A research team from the Cooperative Institute for Research in Environmental Sciences (CIRES) flew over the basin at about 1,000 feet, gathering air samples and taking readings over a period of several weeks. They used a “mass balance” technique which follows an air mass at it moves into a region and then flows out of that area. During their Feb. 3 testing they found that the area leaked 60 tons of gas an hour. Some days it was far greater.

It’s not just the wells that are leaking; methane could potentially be leaking from processing plants, pipelines, and compressors. The problem with all this leaky methane is that it contributes to smog – and Utah has smog levels that rival Los Angeles on its worst days. An EPA report concluded that the oil and gas industry was responsible for about 99 percent of the volatile organic compounds found in the basin which, when mixed with sunlight, creates ground level ozone. The smog was so bad at times that the Salt Lake City airport has had to divert flights.

Add up the studies and you get a picture that shows drilling pollutes the air people breathe, creates smog, and adds a higher-than-predicted burden of greenhouse gases to our atmosphere. Now US Fish and Wildlife Service say drilling is contributing to the loss of two plant species. The agency is asking for federal protection for two rare plant species, Graham’s beardtongue and White River beardtongue and is asking for them to be listed under the Endangered Species Act.

According to US Fish & Wildlife, both plants are endemic to the Uintah Basin and over the past few years their range has been reduced by oil and gas development, invasive species and grazing. The plants grow where oil shale deposits that are rich in calcium carbonate touch the surface.

Wetterling Well- short lived & leaky

photo provided - Wetterling well, Owego

Back in October, Owego residents living near McHenry Road were surprised to see a well rig in their neighborhood. The well was drilled, the rig and truck traffic disappeared, and that was the end of it - or so people thought.


By late October, Carrizo had their exploratory data and were preparing to plug the well. That's when they noticed some bubbling. Gas was leaking between two of the casings.

This new information comes from a pair of DEC inspection reports obtained through a Freedom of Information request submitted by an Owego resident. It makes for interesting reading.

On Oct 25 the DEC inspector notes that gas was leaking at a rate of 15-20 cubic feet a day. The well operator, Carrizo was  concerned about Hurricane Sandy and proposed monitoring the gas leak. A couple weeks later, on November 13, Al Owings of Carrizo calls DEC and asks whether they can abandon the well with a vent pipe.

Notes from DEC investigator: "I told him that I did not know and that NY has no specific regulatory guidelines about the matter."

Now there's a rig back on the pad, and it appears that Carrizo is going to plug the well - the first real "Marcellus" well in Tioga County. Granted, it was a vertical well and drilled primarily to extract data, not gas. Vertical wells, while allowed under current permits, are not the most efficient way to exploit shale gas - but they serve well for exploring the new formations.

The Wetterling well was drilled to 4745 feet, not as deep as some of the wells around the area (some go deep into the Trenton Black River formation around 10,000 or so feet below the surface). There was no horizontal drilling, no hydrofracking. And yet it still sprung a leak.

Methane leaks are not unusual for shale gas wells in Pennsylvania. In fact, citizen reporter Vera Scroggins recently compiled a stack of "Letters of Determination" from PA's Department of Environmental Protection advising homeowners that they have methane - and other contaminants - in their water wells, and that gas drilling activities in the area may have affected their water supply. This is not the kind of letter anyone living near a well wants to receive - whether they live in Bradford County, PA or Owego, NY.

Tom Wilber has posted more about this on his excellent blog, Shale Gas Review.