Analysis of fracking wastewater yields some surprises

Jan 22, 2013

Hydraulically fractured natural gas wells are producing less wastewater per unit of gas recovered than conventional wells would. But the scale of fracking operations in the Marcellus shale region is so vast that the wastewater it produces threatens to overwhelm the region's wastewater disposal capacity, according to new analysis by researchers at Duke and Kent State universities.

Hydraulically fractured natural gas wells in the region of Pennsylvania produce only about 35 percent as much wastewater per unit of gas recovered as conventional wells, according to the analysis, which appears in the journal Water Resources Research.

"We found that on average, wells produced about 10 times the amount of wastewater as conventional wells, but they also produced about 30 times more natural gas," said Brian Lutz, assistant professor of at Kent State, who led the analysis while he was a postdoctoral research associate at Duke. "That surprised us, given the popular perception that hydraulic fracturing creates disproportionate amounts of wastewater."

However, the study shows the total amount of wastewater from natural gas production in the region has increased by about 570 percent since 2004 as a result of increased shale gas production there.

"It's a double-edged sword," Lutz said. "On one hand, shale gas production generates less wastewater per unit. On the other hand, because of the massive size of the Marcellus resource, the overall volume of water that now has to be transported and treated is immense. It threatens to overwhelm the region's wastewater-disposal infrastructure capacity."

"This is the reality of increasing domestic natural gas production," said Martin Doyle, professor of river science at Duke's Nicholas School of the Environment. "There are significant tradeoffs and environmental impacts whether you rely on or shale gas."

The researchers analyzed gas production and wastewater generation for 2,189 gas wells in Pennsylvania, using publicly available data reported by industry to the state's Department of Environmental Protection, in compliance with state law.

In hydraulic fracturing, large volumes of water, sand and chemicals are injected deep underground into at high pressure to crack open shale rock and extract its embedded natural gas. As the pace of shale gas production grows, so too have concerns about groundwater contamination and what to do with all the wastewater.

Another surprise that emerged, Doyle said, was that well operators classified only about a third of the wastewater from Marcellus wells as flowback from hydraulic fracturing; most of it was classified as brine.

"A lot of attention, to date, has focused on chemicals in the flowback that comes out of a well following hydraulic fracturing," he said. "However, the amount of brine produced – which contains high levels of salts and other natural pollutants from shale rock – has received less attention even though it is no less important."

Brine can be generated by wells over much longer periods of time than flowback, he noted, and studies have shown that some of the pollutants in brine can be as difficult to treat as many of the chemicals used in hydraulic fracturing fluids.

"We need to come up with technological and logistical solutions to address these concerns, including better ways to recycle and treat the waste on site or move it to places where it can be safely disposed," Doyle said. "Both of these are in fact developing rapidly."

"Opponents have targeted hydraulic fracturing as posing heightened risks, but many of the same environmental challenges presented by shale gas production would exist if we were expanding conventional ," Lutz added. "We have to accept the reality that any effort to substantially boost domestic energy production will present environmental costs."

The Marcellus shale formation stretches from New York to Virginia and accounts for about 10 percent of all produced in the United States today. Much of the current production is in Pennsylvania. Prior to technological advances in horizontal well drilling and that made the shale gas accessible, the region accounted for only about 2 percent of the nation's output.

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CapitalismPrevails
1.6 / 5 (18) Jan 22, 2013
"We have to accept the reality that any effort to substantially boost domestic energy production will present environmental costs."
Great, so is this guy saying we need to increase domestic energy productions in the deep waters of the Gulf of Mexico? Do we need to increase energy production overseas where there's less private property rights and therefor less threat of a lawsuit if someone pollutes your water? Do we need more energy to be consumed in transportation of oil tankers? Do we need to spend more money/resources on wars over foreign energy? Do we need to spend more money/RESOURCES(energy to make solar grade silicon/extensive power lines/ piles of batteries) on expensive green energy?
Wolf358
3.9 / 5 (7) Jan 22, 2013
"We have to accept the reality that any effort to substantially boost domestic energy production will present environmental costs."

Domestic _fossil fuel_ energy production, yes. But we all know that we need to stop burning petroleum.
TheGhostofOtto1923
1.3 / 5 (13) Jan 22, 2013
"We have to accept the reality that any effort to substantially boost domestic energy production will present environmental costs."
Great, so is this guy saying we need to increase domestic energy productions in the deep waters of the Gulf of Mexico? Do we need to increase energy production overseas where there's less private property rights and therefor less threat of a lawsuit if someone pollutes your water? Do we need more energy to be consumed in transportation of oil tankers? Do we need to spend more money/resources on wars over foreign energy? Do we need to spend more money/RESOURCES(energy to make solar grade silicon/extensive power lines/ piles of batteries) on expensive green energy?
That's a lot of questions. Perhaps this guy can answer them for you.
http://www.e-catworld.com/
VendicarD
2.1 / 5 (11) Jan 22, 2013
CapitalismPrevails provides us with a wonderful example of why America is such a failure as a nation.

"Great, so is this guy saying we need to increase domestic energy productions in the deep waters of the Gulf of Mexico?" - CapitalismPrevails
kochevnik
1.7 / 5 (17) Jan 22, 2013
CapitalismPrevails provides us with a wonderful example of why America is such a failure as a nation.
I can't even read his incoherent tripe. I recognize the words, but they don't fit together. It looks like a Glenn Beck rant when the ADD and borderline schizophrenia resurface
CapitalismPrevails
2.1 / 5 (15) Jan 22, 2013
CapitalismPrevails provides us with a wonderful example of why America is such a failure as a nation.
.

Your a little thick on reading economics aren't you VD. The more you micromanage and make it difficult for companies to do business the more you drive companies to make riskier bets for themselves and everybody else. EG the Gulf oil spill because oil companies weren't allowed to drill in shallower waters. EG the mortgage bubble by forcing banks to make unprofitable loans to people who couldn't afford them. Government intervention just convolutes the natural market and distorts prices.
kochevnik
2.1 / 5 (15) Jan 22, 2013
@CronyismPrevails EG the Gulf oil spill because oil companies weren't allowed to drill in shallower waters.
The BP oil spill happened BECAUSE teabaggers insisted upon allowing drilling in shallower waters. Prior it had been banned.
@CronyismPrevails EG the mortgage bubble by forcing banks to make unprofitable loans to people who couldn't afford them.
Nobody forced the banksters to make loans. Banksters made loans because they were repaid twice by reselling the loan and by staying beneficiary of AIG Insurance. Behind closed doors Moody's colllaterized bad debt with AAA ratings. The MERS database obscured ownership of the debt and allowed loans to be traded over the counter. The USA caused the worldwide depression of 2008. You don't know what you're writing about.
ValeriaT
1.9 / 5 (9) Jan 22, 2013
Shale gas 'worse than coal' for climate. The leaking methane is the culprit here. But without investments into cold fusion research we have not too much other options, how to maintain the energetic sustainability of the contemporary civilization.
bertibus
1.7 / 5 (13) Jan 22, 2013
@kochevnik: Actually banks were forced to make loans by the 'Community Reinvestment Act' of 1977 which was substantially and fatally revised in 1995. It took less than ten years from that revision for the rot to percolate through the system. From the first senetnce of the Federal Reserve's website dedicated to the CRA: "The Community Reinvestment Act is intended to encourage depository institutions to help meet the credit needs of the communities in which they operate, including low- and moderate-income neighborhoods, consistent with safe and sound operations"
Translation: Your institution will come under increasing political pressure to lend in areas where you would not otherwise have lent (and you'd be accused of racism and red-lining for good measure).
As an addendum, please try to frame your arguments without resorting to vulgarities to describe those with whom you disagree.
Caliban
3 / 5 (4) Jan 22, 2013
bertibus,

You invalidate your own argument with this quote because it contains the contradiction which vitiates your premise of "force"

@kochevnik: Actually banks were forced to make loans by the 'Community Reinvestment Act' of 1977 which was substantially and fatally revised in 1995. It took less than ten years from that revision for the rot to percolate through the system. From the first senetnce of the Federal Reserve's website dedicated to the CRA: "The Community Reinvestment Act is intended to encourage depository institutions to help meet the credit needs of the communities in which they operate, including low- and moderate-income neighborhoods, consistent with safe and sound operations"


specifically the last six words:

"...consistent with safe and sound operations"


Which, in banking terms, means only making loans available to well-qualified applicants. NOT subprime loans to people whose income is less than required to pay a mortgage over its full term.

jonnyboy
1 / 5 (9) Jan 22, 2013
hide scott hide
_traw_at
3 / 5 (2) Jan 23, 2013
About the evils of strongly regulated banking, such as found in Canada.:

"...According to the Department of Finance, two small regional banks failed in the mid-1980s, the only such failures since 1923, which is the year Home Bank failed. There were no bank failures during the Great Depression compared to 9000 in the US."
Quote from the 'Banking in Canada' wikipedia article.

Thanks to the deregulation of banks in the US beginning in the 1980s, bank failures can run into the hundreds every year: 92 in the first 11 months of 2012. And most of the 21 Credit Unions which failed had deposits in the low millions- not enough to generate enough money to keep going. [Incidentally, no Federal or State money is used to bail the Credit Unions out: they have their own deposit insurance schemes, paid for by the CUs member/owners.]

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