Marcellus Shale Drilling: Can safe water supply be sustained?


(Part II in three-part series.)
SALEM, Ohio — Oil and water, they don’t mix right? What about oil, water and natural gas? It doesn’t appear they mix either, if the proper precautions are taken by both the landowner and driller.

Concerns over keeping drinking water safe over the Marcellus Shale drilling process is on everyone’s minds.

For example, 13 families filed a lawsuit filed Sept. 13 in Susquehanna County near Allentown, Pa., saying a faulty well drilled by Southwestern Energy Co. of Houston, Texas, leaked fracking fluid into the surrounding groundwater. The suit claims the cement casing in the well was defective.

At one time or another, these concerns and others cross the minds of landowners and residents in a drilling area.

At Penn State University, water resources specialist Brian Swistock has been studying Marcellus Shale drilling and the effects, if any, on water wells.

According to Swistock and others at Penn State, the contamination of private wells and springs can occur, but it has not been common for the past few decades.

Water source concerns also rise around the possibility of something going wrong in the drilling process. Risks include leaking storage pits, the illegal disposal of fracking fluid, site spills, infrequent inspections and the possibility of methane migration to groundwater.

State regs

There are some existing regulations in Pennsylvania to protect the drinking water supply.

The state requires a 200-foot setback from the gas well to water supplies. Drillers are also required to use a pit and tank for the collection of waste fluids.

The state also requires certified mail notification if the water supply is within 1,000 feet of a gas well.

Swistock said there is legislation being considered in Pennsylvania to increase the notification requirement from 1,000 feet to 2,500 feet, but it hasn’t been signed into law yet.


Water concerns often are raised around the hydrofracking process, which is when the drilling water company uses high-pressure fluids to break the gas-producing rock to improve the flow of gas.

Along with large amounts of water, various other materials may be used or mixed with the water for the fracturing process, including sand, oils, gels, acids, alcohol and various manmade organic chemicals.

When the fracking process is completed, the fluid comes back out of the well. It often includes a very high salt content, a high level of total dissolved solids, oil and grease and the additives.

Some residents are concerned this material can contaminate their drinking water supply. However, the cement casing used for the drilling process often prevents contamination, according to Penn State University.

Swistock said some water problems already exist prior to the drilling and often show up in pre-drilling testing.

The problems are usually aesthetic, such as hard water, high iron and a low pH level.

Health effects often have no symptoms, but can include a high level of lead, nitrates and even e-coli.

Swistock recommends property owners focus their pre-drilling water testing on issues related to the drilling and always use a state certified lab for results.

Predrill survey

Everyone who resides or has property where the drilling occurs, or will be located in an area near it, should cooperate with a water survey.

Swistock said drilling companies will often arrange for the survey and if they don’t include it in a lease, it should be required.

The property owner must do his part by cooperating and allowing access for the pre-drilling sample collection.

Who’s testing?

He also recommended that you ask for identification and confirm the testing will be done by an unbiased laboratory (third party, and check to see if it is not owned by the drilling or energy company.)

Swistock said the use of a third party to test the water sample is critical if problems arise after the drilling.

The test will look for the total dissolved solids in the water, barium, pH, chloride and methane gas levels.

Postdrill survey

A water survey is rarely done by a drilling company after it has drilled unless it is stipulated in a lease and, caution experts, they probably will not check for the quantity of water.

However, Swistock said a reduction in a well or spring yield is unlikely. He does recommend getting documentation of the pre-existing well or spring yield.

Swistock also recommends being on the lookout for sediment problems in surface water. He added the highest risk for this happening is when the drilling begins. It will be easy to spot because it will include a change in the water appearance, which could include effervescence, a spurting faucet or a foamy appearance.

Seismic testing

There are no regulations in Pennsylvania or Ohio regarding seismic testing for Marcellus Shale drilling.

However, landowners should stipulate a setback away from their water supply in their leases.

Property owners should arrange for a well or spring yield test before allowing seismic testing near the water supply.

According to Penn State University, the gas well operator is presumed to be responsible for pollution of any drinking water supply within 1,000 feet of the gas well if it occurs within six months after completion of the gas well.

The operator can use any one of five defenses to prove they are not responsible for water contamination including:

• The pollution existed prior to the drilling.

• The landowner refused to allow the operator access to conduct a pre-drilling water test.

• The water supply is not within 1,000 feet of the well.

• The pollution occurs more than six months after completion of drilling.

• The pollution occurred as the result of some cause other than the gas drilling.

Methane gas

One surprising thing to note from Swistock is that something such as methane gas in a water supply can be treated.

Swistock said he considers the treatment “pretty easy.”

He said there are at least two possibilities, including a ventilator wellcap or an aerator system.

Swistock said as the number of new Marcellus Shale gas wells are drilled, keeping surface water safe will become increasingly important across Pennsylvania, West Virginia and Ohio.

(Next week, our final installment.)


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  1. Thanks –this is one of the most level-headed, non-hysterical assessments I have seen yet of the danger to water supplies from gas drilling.

    It should further be noted that there is no danger to large-scale watersheds. The danger presented by gas drilling is very localized –a few water wells in a small radius. When it comes to reservoirs that hold hundreds of millions of gallons of water — or in the case of New York City’s reservoirs, over a billion gallons each — the potential spills, leakage, or methane migration from a gas well will have zero impact.

    • Zero impact? ummm… you know the definition of zero right? Generally 1-8 million gallons of water may be used to frack a well. A well may be fracked up to 18 times. Say they pump water from the bottom of a reservoir for drinking, and the frack water is dumped into a reservoir and it settles toward the bottom? What do you mean zero?

  2. I am curoius GB, where did you get the information that gas drilling will have zero impact?In my opnion, more studies need to be done, namely by the EPA, before we can make such definative statments

  3. GB when you refer to the danger as being “very localized” does that mean you’re o.k. with YOUR water well being contaminated? I invite you to drink and bathe in the water from the contaminated wells in Dimock,PA; Hickory, PA, etc. and then let’s talk about “no danger.”
    It appears that contaminating a water table or water wells is o.k. with you as long as it’s not in your backyard.

  4. Go to a site for citizens to gain insight on impacts from gas shale extraction. Serious attention was never given to documenting and sampling groundwater problems until recently. In Pavillion Wyoming studies now show that there is substantial petrochemical pollution in groundwater near well sites—aditionally there is serious question about migration of methane from casing- their is academic evidence that there is inherant problems in cement shrinkage that may cause leaks and that once this occurs it gets worse–see below.

    When the ‘new’ methods for gas extraction first appeared on the horizon in Pennsylvania, many citizens expressed concern that their water could become contaminated by the hydraulic fracturing process used to obtain natural gas from the Marcellus Shale. At the same time, the natural gas industry’s PR group, the Marcellus Shale coalition, claimed that “hydrofracking has [a] safe record and spurs [the] economy.” Preliminary research conducted by the Agency for Toxic Substances and Disease Registry (ATSDR) and the U.S. EPA in Pavillion, Wyoming suggest that a portion of citizens’ concerns might be warranted. (To learn more, read the PDFs numbered 2, 3, and 4 at the end of this post.)

    Some researchers believe that gas extraction cannot be done without negatively impacting water quality due to the likelihood of well casings leaking over time (Dusseault, 2000). See excerpt below:

    The consequences of cement shrinkage are non-trivial: in North America, there are literally tens of thousands of abandoned, inactive, or active oil and gas wells, including gas storage wells, that currently leak gas to surface. Much of this enters the atmosphere directly, contributing slightly to greenhouse effects. Some of the gas enters shallow aquifers, where traces of sulfurous compounds can render the water nonpotable, or where the methane itself can generate unpleasant effects such as gas locking of household wells, or gas entering household systems to come out when taps are turned on. Methane from leaking wells is widely known in aquifers in Peace River and Lloydminster areas (Alberta), where there are anecdotes of the gas in kitchen tap water being ignited. Because of the nature of the mechanism, the problem is unlikely to attenuate, and the concentration of the gases in the shallow aquifers will increase with time. (Dusseault, 2000)

  5. As I said . . . “non-hysterical.”

    I’m not saying there is no danger. Only that risk is finite and calculable. It is a landowner’s choice to take the chance.

    You all choose to drive a car, I suspect. Yet cars kill 35,000+ Americans each year. And they will spew millions of tons of carbon into our atmosphere. So why do you do such an insane thing? Because you do a risk/reward calculation. The benefit you gain from your car outweighs the risk you face each day — and the danger you cause to others.

    Same with gas drilling. Dimock and Hickory are our crash scenes. You can fixate on them, magnify them, conflate them with all gas drilling — or you can see the larger picture.

    My comment about the risk to large reservoirs being less than the risk to individual landowners is based on a bit of math. We know that a bad drilling job (bad casing usually) can foul a dozen water wells nearby. But what would it take to foul 100 billion gallons in a reservoir? You could dump 1000 lbs. of arsenic into that reservoir and its arsenic level would not rise above EPA’s limit for safe drinking water. So, please explain what event or series of events would make a reservoir’s water unusable. A whole tanker truck of frack fluid crashes and spills? A well blows out and spews brine downstream? They wouldn’t have a measurable effect. And what is the residence time of the reservoir — i.e. how long till it flushes itself out with a new supply of water?

    I’m only asking that people take a rational look at gas drilling, rather than the fear-based emotional reaction it seems to get from many.

    Am I willing to have a gas well on my land? Yes, and I’m looking forward to it. Its benefits to my family are undeniably great, and the risk is minimal.

  6. GB – What about when the circumstances are out of your control? For example, I only own 6 acres and therefore will not have a gas well drilled on my property. I also have a wonderful spring that I get my water from. Now my property is surrounded by two larger properties (128 acres and 300 acres), both of which nobody lives on. Both “neighbors” are interested in having wells drilled, who can blame them with the possible monetary rewards. What happens if my drinking water is contaminated by their wells. They benefit…..were as I most definitely lose. I am not becoming an alarmist, however I have no other water source and surely would not be able to sell my house if has no water supply.

    I am certainly having my water tested in case I have to go to court, for any reason.

  7. To TS…I would be very concerned about your spring fed water source. I hear a lot of conversation and worries of contamination of water and wells…My concern when they drilled around our farm was the LOSS of our springs and wells, which in our case DID happen! A 300 year old farm with 300 year old springs is bone dry…and coincidence that we started losing our water when the gas company around us blasted the rock for their well pads. Our farm now is WATERLESS!! There’s not a DROP of water coming from ANY of our free flowing springs. And how funny we happen to live very near Hickory PA…in fact just down the road, but that is Sheer coincidence!!! I am aware of our “drought” situation…but for our ENTIRE farm to lose ALL of it’s springs and water is just unreal! My suggestion to you would not only to have your water tested, but have your usage and flow monitored also, as when it’s GONE you will be left with open excuses! I have a degree in Environmental Science..I am fully aware of how construction and disturbances can shift aquifers! The problems are NOT just contamination here…there’s SO MUCH MORE!


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