Journalism in the Public Interest

Science Says Methane in PA. Water Is from Drilling, Not Natural Causes

Testing has shown that methane gas in water wells across the country matches the methane being drilled for natural gas supplies. But a woman quoted in a New York Times report hinted that in Pennsylvania—despite state official’s conclusions to the contrary—that may not be the case.


A drilling rig in Dimock, Pa. (Abrahm Lustgarten/ProPublica)

Nov. 10: This story has been corrected.

In its Sunday, Nov. 6, business feature, The New York Times wrote about concerns some residents across the country have about pollution in their water supplies from natural gas drilling. The paper traveled to northeastern Pennsylvania, where more than a dozen residents' water has been fouled by the drilling process and the state is arranging to replace their drinking-water supply.

ProPublica has been reporting on the water concerns there, in the town of Dimock, since late 2008.

At the end of its article, the Times used a quote that raised questions about whether gas drilling is responsible for the contamination, or whether the problem has been made up or overhyped.

The quote came from Martha Locey, a 78-year-old resident of the nearby town of Montrose, Pa., who said she's had methane in the water of her family farm for decades -- long before the drilling started.

"My father dug our well in 1945, and we knew it had lots of iron in it, and we thought it had something else, but we weren't sure, because it had lots of bubbles in it," Mrs. Locey said. "So my nephew took it to school in the '60s, and the science teacher lit it, and it burned, so he said, 'It's methane.'"

Mrs. Locey may be right. It's quite likely that her nephew did in fact light his water on fire almost 50 years ago -- and that the water contained gas. It just wasn't the same type of gas that is causing problems in Dimock.

Methane does occur naturally in water wells, and it is not uncommon in Pennsylvania water. But state officials long ago determined that the methane bubbling up in Dimock's wells was the result of the disruptive drilling processes taking place adjacent to the wells. The gas that typically is found naturally in water wells comes either from methane deposits somewhere near the earth's surface, or from the decomposition of bacteria (this is called biogenic methane).

Scientists have tested the molecular composition of the methane found in Dimock and determined that it came from the Devonian layer of shale, thousands of feet below the surface. In geologic geek-speak, it's called "thermogenic," meaning it is essentially the same kind of gas that the energy companies are drilling for.

Residents in Dimock and across the country have found thermogenic gas in their water where drilling is taking place. Many people are blaming the invasive and controversial drilling process called hydraulic fracturing, and federal authorities are studying whether that process in particular is endangering water supplies in several states. But whether it was fracking or some other part of the drilling process -- the construction of the wells, for example -- there is little debate among regulators and scientists that the contamination in Dimock is related to the drilling.

Correction: This story incorrectly stated that well water had been fouled in northwestern Pennsylvania. The story should have said the water was fouled in northeastern Pennsylvania.

Inform our investigations: Do you have information or expertise relevant to this story? Help us and journalists around the country by sharing your stories and experiences.

Is there a link to or a reference for the science study?

Thanks for the continued reporting.  However Dimock is in NorthEATERN PA.  In your intro you state the New York Times reached northwestern PA.

That’s eastern. Northeastern.  Ooops.

“Science also says” that there is ZERO evidence that anything else is entering the watershed. That includes all those nasty chemicals used in gas drilling. The only documented case of thermogenic gas entering the water table where baseline data on water quality was available and investigated showed that there wasn’t ANY trace of drilling fluid in the water table. And if methane in water supplies has always been an issue on some properties (contrary to Josh Fox), does that mean that what happened in Dimock is of much concern?

Thank you Mike H for providing the fair and balanced view of the gas industry.
As for the rest of America, the answer to your question is a resounding YES.  We are all concerned about what has happened not just in Dimock, but in many other communities from Texas to Colorado to Wyoming.  If the gas is getting in the well, the drilling fluids can’t be far behind.  Why aren’t they found? 
1.  Because they are heavier and take longer to infiltrate to the surface, and
2.  Because once the water is found to be contaminated with gas, people tend to stop using the well (rather than continue to use until the fracking fluids come out as well).

BTW Mr Lustgarten, I have a huge heaping plate of crow for you once the EPA’s preliminary study in Wyoming comes out early next year.

Bon appetite.

A wise man once said that it’s hard to get someone to admit the truth about the wrong they are doing, especially when their paycheck depends on it. The commenter “Mike H” could well be that kind of fellow. It is amusing to think of someone relying on the EPA or any US government agency to tell the truth about the fossil fuel industries that own our government and politicians. The movie Gasland pretty well nails it, and it doesn’t take a genius (only an honest person who has a conscience) to figure out why frackers don’t want anyone to know the mix of toxic chemicals in the witch’s brews that they inject into our earth. Having worked in geology I can tell you that most people in the fossil fuels industry would sell their mothers to the devil if it meant getting at profits. These folks are murderers of mother earth. They need to be stopped.

I lived for 20 years about 30 miles north of Montrose in New York, and still have friends there and in Steuben county NY where there is already some drilling. Keep tuned because this whole issue has the potential of playing itself out in a classic story of greed, resentment, betrayal, and violence. From what I understand most of the communities where the drilling is occuring were once typical tightknit but poor rural communities, but now they are turning in community versions of the Treasure of the Siera Madres with gas instead of oil and whole communities instead of a few miners and bandidos. Apparently people are getting very angry when drilling occurs on one persons land who instantly becomes a millionaire and all the surrounding neighbors are as poor as ever, but now have unuseable well water.
P.S. These people are all hard drinking NRA members who love to hunt.

I live in NY, not far from Dimock, PA, and I have been following the water issues in Dimock with great interest, because my own area may experience shale gas drilling in the near future.

The PA DEP has not only performed laboratory testing that indicates that the methane found in some Dimock water wells came from a deep Devonian layer, they have also observed gas bubbles and high pressure readings at some of the gas wells operated by Cabot Oil and Gas. According to the DEP, the bubbling and high pressures are signs that the gas wells were improperly constructed.

In my opinion, the NY Times article should have detailed the DEP’s evidence for Cabot’s guilt in the Dimock water contamination. Without that evidence, it sounds like a case of one person’s word against another’s. But with the DEP’s evidence before them, I think most reasonable people would conclude that Cabot is to blame.

The Eric makes an interesting comment, because we do not find links Citati on the text. That is, study for others to read. There are positive consideration, yes. Because they see the nature side of the planet. This methane if it had not been touched by the exploitation of water, that methane would never come in contact with the atmosphere. Therefore, should not always look as if water contaminated by methane, or even a water-absorbing methane which in turn is extremely toxic to humans and living beings in general. This water can be the solution but to keep that methane in the sub soil, instead of being in the atmosphere. If this is natural in the water, he must stay in the basement with water and this water should not be withdrawn because of that methane is not harnessed and will only be in the atmosphere contaminating every living thing. If this is clean water, and methane was injected, need to see why the injection, if by accident, should be recovered. Now if injected by the will of engineering is why this is in excess methane in the atmosphere and killing people. At least deep underground, that methane will not hurt any living thing. And water can be sought from other sources.

What happens if this gets into a major water source for a large city?

I am still waiting to receive a response concerning the science study. Who conducted the study? Where is the report? How was the study conducted? My inclination is to distrust the drillers and error on the side of protecting the environment and water supplies. However, the longer you remain silent, the more I doubt your credibility.

In reply to Eric: The study of the Dimock contamination cases was conducted by the PA Department of Environmental Protection. I don’t know of an online link to the actual PA DEP report, but the DEP may be able to provide you with that report.

I left a couple of earlier messages with some links that might interest you, but the messages were held for moderation.

If you search for the PA DEP news release page, you will find a link there to a 10/19/10 open letter to Susquehanna residents from PA DEP Secretary John Hanger. In a paragraph near the end of that letter, Sec. Hanger summarizes the DEP’s evidence for Cabot’s guilt.

In addition, the PA DEP recently released a video of gas bubbling at Cabot wellheads in Dimock. The video was released to WBRE-TV and can be viewed at WBRE’s PA home page.

You may also be interested in the fact that, after hearing the DEP’s evidence, the Pennvest Board recently voted 10-2 vote to fund a water line to bring safe water to Dimock. Pennvest’s decision was reported by the Scranton Times-Tribune and you can read about it there.

To Mary: Thank you so much for this! It is always nice to gather some solid, scientifically based evidence.

Mary Sweeney

Nov. 12, 2010, 11 a.m.

To Eric: You’re welcome, and I agree that it is important to gather solid, scientifically based evidence.

Oil and gas giant Halliburton on Monday launched a new section of its website identifying many of the chemicals it sells to natural gas drillers in Pennsylvania to hydraulically fracture Marcellus Shale gas wells. See for yourself what gas drillers are injecting underground at

The background methane gas long generally found in wells in the Dimock area is Upper Devonian.  The gas found at well heads in the area is also Upper Devonian.  There is no scientific predicate for your statement that the gas Martha Locey found recalls from 1945 is different.  In addition your statement that the gas found in local wells is “... essentially the same kind of gas that the energy companies are drilling for.”  is also incorrect.  The gas energy companies are presently drilling for is that found in the Marcellous shale and it has a different isotropic signature than Upper Devonian methane and no one, including DEP, has claimed any of it has been found in our wells.

According to the PA DEP’s lab tests, the gas in the Dimock water is from a Devonian layer that is far below the aquifer, but not as deep as the Marcellus, so Bill is correct that it is not Marcellus gas. However, it is gas from a layer that the gas wells had to pass through on their way to the Marcellus, and the DEP believes, based upon their investigation, that poorly constructed gas wells created one or more pathways for that gas to enter the water supply.

If Bill’s statement that the gas that entered the water in 1945 was also from a Devonian layer were correct, then I think that would mean that there is a natural pathway somewhere that allows gas from the deep layers to reach the aquifer. If that were the case, then I think that drilling and fracking in the Dimock area would be a very risky endeavor, since the fracking fluids, which are forced into the ground in high volumes and at high pressure, could presumably travel the same natural pathway that allowed Devonian gas to enter the water back in 1945. I am not saying that this IS what happened, and please note the DEP has made no such allegation—again, the DEP thinks the pathway was created by faulty gas wells. However, I do not think the scenario that Bill describes is particularly comforting or that it would let Cabot off the hook, since Cabot should be certain before it drills or fracks that there is no communication between the aquifer and the deeper layers where thermogenic, Devonian gas is held.

In reply to Mary:  As noted earlier, it is my understanding that thermogenic Upper Devonian deerived methane gas has not been uncommon at some level within water derived from aquifers within our area.  Indeed PSU has for many years published an information paper for homeowners cautioning them on the need to check for the presence of methane in well systems and how to remedy excess levels. These Upper Devonian sources are a very great distance from the MarceIlus shale and even DEP has clearly stated that no fracking fluids or Marcellus shale derived methane has been found in any of our water sources.

In reply to Bill: If there has been thermogenic gas from deep Devonian layers in the water in the Dimock area for decades, that would indicate that there is some communication between deep Devonian layers and the aquifers. The gas industry has stated over and over and over again that there is no communication between the aquifers and the deep, thermogenic-gas-bearing layers; this is, in fact, a key point in their argument for the supposed safety of fracking.

Actually, though, I question whether the gas that has been reported in Dimock water prior to gas drilling in that area was thermogenic or biogenic: I haven’t seen any laboratory evidence either way, so if you know of reliable lab work to indicate what was going on in 1945, then please let us know where we can see it. I’m not being sarcastic: I think that part of the problem with fracking is that no one—including the gas industry—has made a thorough enough study of Northeastern geology to allow a reasonable estimate of the safety of shale gas extraction. This is not just my opinion, it is also the opinion of the NYC DEP and of many reputable scientists.

And again, I will remind everyone that the PA DEP not only has lab work matching the gas at Cabot wellheads with the gas in the water supply, they also have evidence that some of the gas well casings were faulty. Instead of admitting its mistakes and taking responsibility, Cabot has constantly tried to find some alternate explanation for the very visible problems in Dimock. At this point, I doubt that there are many drilling proponents in NY or PA who would be eager to sign with Cabot, and that is Cabot’s own fault.

This article is part of an ongoing investigation:

Fracking: Gas Drilling’s Environmental Threat

The promise of abundant natural gas is colliding with fears about water contamination.

The Story So Far

The country’s push to find clean domestic energy has zeroed in on natural gas, but cases of water contamination have raised serious questions about the primary drilling method being used. Vast deposits of natural gas, large enough to supply the country for decades, have brought a drilling boom stretching across 31 states. The drilling technique being used, called hydraulic fracturing, shoots water, sand and toxic chemicals into the ground to break up rock and release the gas.

More »

Get Updates

Our Hottest Stories