Tuesday, March 26, 2013

Dimock water problems continue after four-plus years Results of recent cases in fracking zone not yet released

Crews use a service rig in Dimock to diagnose problems
DIMOCK, Pa. -- More than four years after the explosion of a residential water well called attention to the problem, Pennsylvania environmental officials are still trying to solve water pollution in this small town that has become infamous for shale gas development.

Recent cases involve two homes in a gas field where the Pennsylvania Department of Environmental Protection has banned drilling of new wells in the wake of chronic water pollution tracked to nearby operations of Cabot Oil & Gas. Cabot crews continue to operate a service rig between gas wells and water wells to diagnose problems in an area where the DEP has found dangerous levels of methane flowing into residential water wells near the junction of Carter Road and State Route 3023.

Colleen Connolly, a spokeswoman for the Department of Environmental Protection, said this week that the agency has not determined when the latest round of testing will be released.

Cabot has been cited in the past for various violations that the DEP has linked to problems. Wells providing water to several dozen homes have been taken off line or fitted with filtration equipment to remove gas and other pollution since the water well of Dimock resident Norma Fiorentino exploded on New Year’s Day, 2009.

Although drilling has been banned in a nine-square mile area where problems are the worst, the DEP recently allowed fracking to stimulate production of exisiting wells. Two months ago, DEP officials responded to complaints that drinking water at several homes became turbid after crews fracked nearby natural gas wells.  Subsequent tests showed two water wells serving homes along State Route 3023 contained explosive levels of methane, according to information from the DEP.  Cabot Spokesman George Stark did not return calls for comment. In the past, he has said the problem may be linked to a frozen vent.

In addition to methane, the DEP is testing water samples taken from affected homes for various other contaminants, including metals and chlorides (listed below), which are markers for pollution from gas drilling and production.

With the recent announcement that DEP Chief Michael Krancer is stepping down, the problem will be passed on to the third administration. In 2010, John Hanger, who served as Governor Ed Rendell’s top environmental official, found that shale gas operations had ruined the aquifer serving homes in and around Carter Road. As a remedy, Hanger ordered Cabot to build an $11 million pipeline to restore fresh water to affected homes. After the order, Cabot denied that it was responsible for pollution, and the pipeline order was eventually defeated amid political opposition when Tom Corbett, a drilling supporter, was elected governor.  Last August, Cabot reached an undisclosed settlement with 32 of 36 Dimock families suing for damages related to pollution of water wells.  Other lawsuits are pending.

In an investigation last year, the federal Environmental Protection Agency found elevated levels of arsenic, barium, manganese, or methane, in five of 64 water wells – roughly 8 percent. It concluded that the concentrations could pose health risks, but those risks were mitigated by treatment systems drilling companies had installed or planned for the homes. The federal Agency for Toxic Substances and Disease Registry is now following up with an evaluation of it’s own.

Early this year, the DEP came under fire about how it handles testing at sites suspected of pollution from gas development. In January, Pennsylvania Auditor General Eugene DePasquale announced a review of the agency’s regulation, testing and enforcement program. The intention of the probe, according to a letter from DePasquale to Krancer, is to determine the "adequacy and effectiveness of DEP's monitoring of water quality as potentially impacted by shale gas development activities, including but not limited to systems and procedures for testing, screening, reporting and response to adverse impact such as contamination."

The recurring problem of pollution related to shale gas and related public relations issues will be inherited by Krancer’s successor.

While methane migration is not unique to Dimcok, the rural community has been divided by the issue, and is featured as a case study and focal point of the anti-fracking movement just across the state border in New York, where fracking is on hold pending a more extensive review of environmental and health issues.

What the DEP is testing for in Dimock water wells:
Source: DEP 


  1. Tom,
    The constituents listed above are classic metals and some of the "wet chemistry" parameters. The last three are the lightest hydrocarbons typical of natural gas: methane, ethane and propane.

    The list seems couched or coached by lawyers so either the results can be argued as natural or regularly occurring in the aquifer.

    A list should include obvious "tell tale" constituents from fracking operations - beyond argument except maybe to the most expensive white shoe lawyer.

    For instance, chemicals from fracking operations have been disclosed in general terms. These would be emulsifying agents, petroleum hydrocarbons in the gasoline and diesel fuel range (including aromatics and aliphatics), biocides and possibly chlorinated hydrocarbons. Others obviously exist. But these chemicals simply have no reason to be in the aquifer unless a shale gas fracking fluids manufacturing facility happened to be located upgradient of the area in question.

    The issue relating to Dimock seems to be methane and other constituents entering the groundwater supply via subsurface intrusion from either the well casing or from rogue fractures emanating from the horizontal run of the well. A rogue fracture would be one that doesn't stop within a predicted distance from the horizontal run. But instead continues up toward the surface. This situation puts the fractured zone in direct communication with the saturated zone of the aquifer.

    Water samples should be analyzed for constituents mentioned above, plus the following:

    * Liqht hydrocarbons heavier than propane including butane through octane. These constituents could be directly natural gas seepage via rogue fractures. These constituents can be traced back to the natural gas collected at well heads (the natural gas liquids).

    * Aromatic hydrocarbons such as benzene and toluene. A similar situation as the above point, but these chemicals are listed in the SDWA and have MCL values.

    * Fractured zone formation chemicals including metals, radionuclides (radon and other) and inorganics common of the shale formation, which may easily dissolve or become suspended in water. The origin of these chemicals can be determined from well bore samples collected during drilling.

    Great article Tom. I'm simply adding a "for whatever it's worth" comment.

    1. The list does include bromine, which is a pretty good indicator of frac fluid pollution. The natural background level of bromine is quite low, while many biocides used in frac fluids contain it. It would be more conclusive to analyze for several chemicals in the frac cocktail, but that gets expensive, assuming that you know what to look for.

      That said, the frequency of pollution of aquifers by frac fluids is small compared to pollution by shale gas. This is probably what has been, is, and will be happening in Dimock and at scattered location through the Appalachian Basin. Either the concrete seal of the casings are leaking or the vibration and pressures of drilling and fracing are speeding the natural leakage of shale gas up through the rock layers. Either way, only way to "prove" in court that industry is responsible is to have baseline tests which show low levels of methane, ethane, and propane before drilling.

      Of course the industry has its record of claiming that all gas in people's water wells is a natural, preexisting condition. So much for safe and responsible drilling.

    2. It's certainly possible that contamination by fracking fluids is a less frequent problem than methane contamination--maybe far less frequent. But I question whether we actually know how frequently fracking-fluid contamination occurs:it does not seem as if there has been a truly comprehensive and unbiased attempt to study this question.

      Also, since we know that leaking gas well casings are a common problem, I've been wondering for some time now what would happen if a gas company were to frack a well that had a leaking casing. Another consideration is that fracking fluid might make it into the aquifer through an uncased, abandoned gas or oil well in the vicinity of the modern, fracked well.

    3. pCBB and Mary, All good points. To pCBB’s point, yes, the burden of proof becomes a barrier for many landowners who want to challenge the industry, which typically strives settle questions behind closed doors before lawyers even become involved. The bigger and more influential the landowner, the more compensation the company has to produce. So the small guy with a few acres next to a drilling unit often goes under represented in these conflicts.

      Regarding Mary’s idea that fracking + bad casing = problems is supported by this case, documented by the Ohio Division of Mineral Resources Management.


    4. pCBB, well said. You're right about how shale formation fluids can migrate through the subsurface, whether through manufactured or natural fractures. The premise of extracting fluids from shale is that the lions share of hydrocarbon lies within the macro fractures not necessarily the interstitial pores. The purpose of manufactured fractures, with an almost infinite surface area (compared to a conventional well bore screen, is to intercept the naturally occurring fractures. Upon fracturing, a molecule will move either from the formation into the well or up to the surface - depending on the pressure differential driving force. So maybe a rogue fracture perturbation doesn't have to go that far up and away from the horizontal run - just far enough.

      What really gets my goat is the lack of research and operations data on the subject of safe drilling distance between the formation and the aquifer be it site specific or general characterization. It really seems like O&G and State regulators are just guessing. There was one paper somewhere on rogue fractures (out of the UK) and that's about it. The research was only a statistical analysis from driller supplied data - not a field experiment. The US researchers and industry have been almost silent on this subject. Except some of the hallowed shale gas and oil research institutes popping up in strip malls next to local and national universities. They all seem to prove shale gas and oil is safe, dammit.

  2. Michael, Thanks, as usual, for your informed comments. I have heard from various sources that the chlorides are markers for formation pollution that might typically include some of these other things you mention, so chlorides and these other tests serve as primary analysis. There is, as you know, a lot of controversy over what gets included, and what gets reported, in these tests, and I agree the issue warrants more attention and inquiry along the lines you suggest here.

  3. thank you for this synopsis...I have been asking for information since we live a short distance from this gas well. You pose a question-whether the methane increases are related to fracturing back in the affected area or if it is part of the "original" problem. I hope folks would want the answer to that since the industry is just getting started here in NEPA. Thousands of wells and dozens of compressor stations are on the way. We need to be vigilant and demand accountability, responsibility and the highest standard of industry operations that are available-not just what is required. We need the industry to care about the quality of the lives of the folks who just happen to live in the middle of their gasfield.

  4. Some more information on fracking and well casing failures, from a recent accident in Texas:


  5. If you are interested, he is a well by well review of EPA Data for Dimock - http://www.water-research.net/dimockwellwater.htm