Author’s Note: This is the most technically complex column I have attempted to share with you in the 3.5 years I have been publishing Common Science. The issue of methane contamination of water wells is important and much of the reporting on it has been incorrect, so, to me, this is an important piece. I ask that you give it a try and email me at firstname.lastname@example.org with any questions.
This is the conclusion of a two-part series of the implications and potential hazards of methane contamination of drinking water wells due to fracking. Part I explained how we know that fracking allows methane to infiltrate drinking water aquifers, and reviewed the associated toxicity implications. For the purposes of this week’s column, the key point to know is that a recent Duke University study demonstrated that drinking water wells near to fracking operations in New York and Pennsylvania had methane concentrations of up to 70 mg/L, a level many times greater than normal. Since methane, the primary component of natural gas, is quite flammable, the question I will address this week is what level of methane contamination in drinking water wells represents a fire or explosion hazard.
The graph above from the Duke Study shows the elevated concentrations of methane in well water near to fracking operations. Please note the gray band labeled “Action Level for Hazard Mitigation (US Department of Interior)” as I will be referring to it below.(1)
In order to evaluate the potential hazards stemming from methane contamination of water wells, we need to discuss some thermodynamics.(2) Methane is a flammable gas, but like all flammable gases, it can only burn in air at certain concentrations. If the concentration is too low, there is not enough fuel to sustain a fire. If the concentration is too high, there is not enough oxygen. (Essentially, the methane crowds out the oxygen.) For methane to burn when mixed with air, its concentration must be between 5 and 15%, which are known as the lower and upper flammability limits. Therefore, in order to avoid a methane fire or explosion, we need to avoid creating a vapor mixture with 5-15% of methane in air. This is almost always accomplished by keeping the methane concentration at less than 5%.
Now that we know what concentrations of methane-air mixtures are flammable, the next question for us is, “How much methane must be dissolved in my well water such that a flammable mixture of methane and air can be created?” To answer this question we need to discuss the vapor liquid equilibrium (VLE) for methane and water shown below.
The X axis on this graph shows concentrations of methane dissolved in water in milligrams per liter (mg/L). The Y axis shows the percent methane in the air above the liquid. The diagonal line represents the conditions when the liquid and vapor are in equilibrium with one another. I will explain what that means using the example below.
Start on the X axis and find 5 mg/L of dissolved methane. If you move straight up from there, you will hit the diagonal line at 2.5% methane in the vapor. What this means is that if I make a solution of 5 mg/L of methane in water and put it in a closed container, methane will evaporate out of the liquid until the vapor concentration reaches 2.5%. The reverse is also true. If I were to start with pure water and introduce a vapor mixture of 5% methane above it, methane from the vapor will dissolve into the water until a concentration of 5 mg/L is reached. At these conditions, the vapor and the liquid are in equilibrium which means that methane evaporates from the water at the same rate that is dissolving back in from the gas. This is what equilibrium means in this context.
Now that we know how the VLE graph works, let’s consider the data for 10 mg/L of dissolved methane, a concentration just high enough that the DOI recommends mitigation. In this case we see that a vapor concentration of 5% methane would be created in a closed container. As we discussed above, 5% is the lower flammability limit for methane. Since a 10 mg/L solution of methane in water has the potential to create a flammable vapor mixture above it, the DOI uses 10 mg/L as the lower limit for its action level range.
Consider again the example of water with 10 mg/L of dissolved methane, but this time let’s put it in an open container. In this case, methane evaporating from the water into the vapor space above can waft away. In most circumstances, it will float away at a rate faster than it can evaporate from the water. Therefore, the vapor space above the water cannot build up a concentration of 5% methane – the lower flammability limit – and thus cannot burn or explode. Additionally, over time in an open system, eventually nearly all of the methane initially dissolved in the water will be gone.
The issue of closed versus open areas or containers is vital to evaluating the potential hazards of methane-contaminated water wells. The first place to look for fire and explosion risks in a home water system are closed spaces where methane vapor can accumulate. In a typical home water well and supply system there are two potential trouble spots: the well head and the pressure tank. The diagram below of a typical home water well system should help illustrate the potential problems.
When installing a water well, you start by digging a 4-6” diameter hole into the ground until you find the water table, typically 100-500 feet in this neck of the woods. The top portion of the large hole is protected with a steel and/or concrete casing to prevent it from collapsing. At the top of the casing there is a cap called the well head. Then a pump is placed near to the bottom of the well which pumps water up to the surface through a thin (1-2”) pipe which runs up through the well casing to just below the ground surface and then into your house.(3) Once inside your house it feeds a pressure tank which has a flexible bladder inside. The bladder supplies pressure which allows water to flow to the faucets, showers, toilets, and appliances in the house. When the pressure in the bladder drops due to water use, a pressure switch turns on the well pump, refilling the bladder, until the pressure goes back up and then the pump is turned back off.
The most likely place for methane to accumulate in this system is at the top of the well casing below the well head. Methane in the aquifer can evaporate and rise up in the space outside of the thinner water delivery pipe. In circumstances where the aquifer contains more than 10 mg/L of methane, the presence of a flammable mixture below the well head is quite likely. On occasion, well head fires and explosions have been reported when the well head is opened in the course of maintenance activity. This potential hazard can be mitigated by installing a vent on the well head to let the methane escape and float away. Note that while this will prevent the formation of an explosive atmosphere, it creates an open pathway for the methane, a potent greenhouse gas, to enter the atmosphere.
The second potential place for methane to accumulate is in the vapor space of the bladder inside the pressure tank. As we learned in our discussion of the VLE diagram, when the concentration of methane builds in the vapor space, more and more of it will dissolve into the liquid. This dissolved methane will escape into the house when you use your faucets, showers, and toilets. This is the mechanism purported to be behind the famous scene in the movie Gasland when a man lights a fire in his kitchen sink. Because the sink is an open rather than closed environment, it is difficult (but not impossible) to create a flammable mixture of methane vapor in the sink. But having methane accumulate in your pressure tank can create a possible fire hazard, and attempting to mitigate this situation seems to be the prudent course of action.
Fortunately, it is not difficult to prevent the accumulation of methane it the bladder of the pressure tank. Unfortunately, the solution is expensive. The way to remove the methane is to have the well pump first deliver the water to an unpressurized, vented tank outside the house. The methane in the water will evaporate and exit through the vent of this tank. This process can be sped up by bubbling air through the water. Then the now methane-free water from this tank must be pumped into the bladder of the pressure tank to service the house. The extra tank, pump, and associated valving and controls for this design are not cheap!
As I have outlined, the fire and explosion risks of methane-contaminated well water can be addressed by venting the well head and adding extra tanks, pumps, and bubblers, at least in theory. But the real world often does not care too much about theory. Since the aquifers in North Carolina are not currently contaminated with methane, our wells generally don’t include these safeguards. When fracking does begin here and methane starts to infiltrate our drinking water, I believe that it is unrealistic to assume that these safeguards will be installed in all, or even a substantial portion, of the wells. Who would pay for it?
Furthermore, let’s step back for a moment and consider what is really happening here. First, the drilling companies are creating a pathway for methane from underground natural gas deposits to reach the aquifers. Then if we make the changes to our water systems I described above in order to prevent fire and explosion hazards, we will be venting methane into the atmosphere!
This is not an acceptable situation. If you cannot demonstrate that you can extract natural gas without getting methane into our water, you should not be allowed to frack.
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(1) I contacted the Department of the Interior while researching this column and wanted to note how very pleasant and helpful they have been. The issues of methane contamination are managed by the United States Geological Service (USGS). They were prompt and informative in answering my questions and told me that a baseline study of ground water methane in Lee and Moore counties was underway. Our tax dollars at work!
(2) Long-time readers will know that my father is an emeritus professor of chemical engineering at Penn State. Much of his work centers on thermodynamics, so I suspect that upon reading this he is smiling.
(3) It stays buried underground like this so it won’t freeze during the winter.http://chapelboro.com/columns/common-science/methane-water-part-ii-fires-explosions/
The third of four scheduled public hearings on proposed safety rules for fracking in North Carolina takes place 5 p.m. Monday at Rockingham County High School in Wentworth.
The previous two meetings before the Mining and Energy Commission were held at N.C. State University’s McKinnon Center last Wednesday; and two days later at Wicker Civic Center in Sanford.
Five hundred people attended the Raleigh meeting, and most of the speakers who addressed the commission were opposed to fracking.
Pittsboro resident Sarah Wood, who described herself as a mother of a 2-year-old, asked for a moratorium on fracking, and posed this question to the commission members:
“Would you feel comfortable living within a mile of a fracked well? Would you really feel comfortable living that close? And if the answer is no, that you would no feel comfortable living that close to something that’s potentially that toxic, then it’s your moral duty to protect those who are going to be living that close.”
Only around 200 people attended Friday night’s hearing in Sanford, but the emotions were just as high.
Eighty-six citizens from around the state – again, most of them opposed to fracking – spoke at that hearing. Like the first one, it was marked by occasional boos, snickering and other displays during comments by a handful of fracking supporters.
Back in June, North Carolina Gov. Pat McCrory signed a bill into law that allows permits to be issued for hydraullc fracturing, or fracking. By this method, underground rock is fractured by pressurized liquid to release natural gas.
Opponents say they’re concerned that toxic chemicals used in the process will seep into drinking water. Supporters say they envision more jobs, and increased energy independence.
The fourth and final public hearing before the Mining and Energy Commission is scheduled for Sept. 12 in Cullowhee, which is in Jackson County.http://chapelboro.com/news/state-news/next-fracking-rules-hearing-held-monday-rockingham-co/
In recent weeks, there have been many reports in both the local and national media regarding a study published by Duke University showing elevated methane levels in drinking water wells located near fracking operations in New York and Pennsylvania. In my opinion, these reports do not provide sufficient information for the reader/viewer/listener to evaluate the fundamental question, “How worried should I be?” In this two-part series, I will attempt to provide a comprehensive answer to that question. To do so, I am going to have to delve a bit deeper into technical details than normal. However, with fracking coming to the Tar Heel State, I think it is important for this issue to be addressed accurately and comprehensively. So pour yourself a fresh cup of coffee and let’s get to it.
Let me start with a one-paragraph primer on fracking. First, a drilling company locates an underground deposit of natural gas, which is a mixture composed primarily of methane along with small amounts of ethane, propane, and butane. Next, the company drills down to the depth of the gas deposit and protects the well bore with steel piping encased in a layer of concrete. From the bottom of the vertical well, horizontal holes are drilled in several directions. Then a high-pressure slurry of water, sand, and chemicals is pumped into the horizontal holes, fracturing adjacent rocks. Fracturing the rocks allows the natural gas in the deposit to migrate to the vertical well bore, and subsequently to be brought up to the surface. Many of the chemicals used in the fracking process are highly toxic. (1)
As we consider the issues discussed below, an appreciation for depth will be helpful. Water wells for drinking and agriculture are almost always less than 1,000 feet deep, because that is where the water is. Fracking wells tend to be much deeper, 2,000 to 20,000 feet, because that is where the natural gas is. The separation in depth between underground aquifers and fracking operations is a critical parameter in trying to avoid water contamination. If fracking occurs at depths which are too close to aquifers, then cracks can extend from the fracking zone into the aquifer and allow fracking chemicals to contaminate the water. I have previously written about a case of this occurring in Wyoming. The physics of fracking suggest, at least to me, that the separation in depth between an aquifer and any fracking activity should be at least 1,000 feet.
The graph above, from the Duke University study, shows methane concentrations for water wells as a function of distance from fracking operations. The data clearly show that water wells closer to fracking operations have higher concentrations of methane. This graph contains a lot of information and implications, and, thus, raises a number of questions which I will attempt to answer below.
What is the source of the methane?
The two most common sources of methane in ground water are bacteria in the soil and natural gas deposits. Drilling companies frequently raise the possibility of multiple possible sources in order to suggest that methane found in ground water may not be related to their activities. However, it is actually quite easy to determine the origin of methane found in a water well. When bacteria are going about their business, they make methane and only methane. In contrast, methane from natural gas, which is produced by the decomposition of ancient organic matter deep underground, is accompanied by other decomposition products such as ethane, propane, and butane. Since the water in the wells from the Duke study contains these other hydrocarbons along with methane, there is little doubt that the methane they found was from natural gas.
Did the methane reach the underground aquifers due to fracking?
As you look at the graph above, the answer seems to obviously be “yes.” However, drilling companies have claimed that the methane may have infiltrated local aquifers prior to the fracking operations and that since the Duke study does not have baseline data collected prior to drilling, causation has not been established.
While the assertions from the drilling companies are defensible on the surface, they don’t stand up to scrutiny. Consider that all of the water wells in the Duke study are over the same shale formation that bridges the New York/Pennsylvania border. If methane in that zone was naturally migrating into the aquifers, one would expect that nearly all of the wells would be contaminated. To accept the drilling companies’ explanation that their activities are not related to the water contamination, one would also have to accept that somehow they have only drilled near to previously contaminated aquifers and that the aquifers in areas where they have yet to drill have somehow avoided the onslaught of naturally migrating methane. The odds of the drilling companies’ theories being correct are infinitesimally small.
The explanation posited by the Duke researchers is that methane is reaching the aquifers adjacent to the fracking wells by leaking through cracks in steel piping and concrete casings around the vertical well bores. I find this explanation to be far more compelling.
Is methane toxic?
The short answer is no. Methane is essentially inert and will not undergo chemical reactions except at very high temperatures. Therefore, any methane dissolved in water that you drink will pass through your body without causing any harm. Further, as flatulence can contain up to 10% of it, methane is not unfamiliar to your gastrointestinal system.
Is methane a harbinger of other pollutants?
The essence of this question is, “If methane can migrate from the fracking zone to the aquifer, can harmful fracking chemicals such as benzene do so as well?” To explain why the answer to this question is “not necessarily,” we need to talk a little chemistry.
Methane consists of a single carbon atom in the middle attached to four hydrogen atoms. Since the four hydrogen atoms are arranged symmetrically, methane is non-polar. What this means is that the electrons within a methane molecule are evenly distributed, which results in the characteristic that methane molecules tend not to stick to each other or to anything else. Methane is also a very small molecule. Since it is small and doesn’t stick to anything, methane can worm its way through very small cracks and fissures.
Molecules which are polar have a much more difficult time migrating from place to place underground. As an example, let’s consider water (H20), a molecule about the same size as methane. In the case of water, the two hydrogens are not symmetrically arrayed around the central oxygen atom. As a result, part of a water molecule is electron rich while the remainder is electron deficient. This has the effect of making water molecules act like little magnets such that they stick to each other and many other things, like soil and rock. So it has a much harder time migrating underground.
The chemicals used in the fracking process are both much larger than methane and tend to be polar like water, limiting their ability to migrate. Therefore, the fact that an aquifer has been infiltrated by methane is not a particularly strong indicator that fracking chemicals will soon arrive.
To sum up Part I, what we know so far is:
Next week in the conclusion of this series, I will discuss other potential hazards of methane contamination of water wells, particularly fires and explosions.
Have a comment or question? Use the interface below or send me an email to firstname.lastname@example.org. Think that this column includes important points that others should consider? Send out a link on Facebook or Twitter. Want more Common Science? Follow me on Twitter on @Commonscience.
(1) Although the North Carolina General Assembly recently voted to make it illegal for a citizen of the Tar Heel State to disclose the identity of chemicals used in fracking here in the southern part of heaven, as I explained in Fracking Gag Rule Part I, everyone already knows what they are.http://chapelboro.com/columns/common-science/methane-water-part-toxicity/
With the rising concern of the dangers associated with fracking, many North Carolinians are deeply uncertain about what lies ahead for the state relying on the questionable method of obtaining fuel and energy.
WCHL’s Ron Stutts spoke with Therese Vick of the Blue Ridge Environmental Defense League, and with Martha Girolami, a citizen of northeast Chatham County that has found out recently that she lives atop of what is known as the “Triassic basin,” which is one of the potential locations that fracking companies may take advantage of.
The Blue Ridge Environmental Defense League is a “regional, community-based, non-profit environmental organization.” They focus on issues including “industry’s dependence on toxic chemicals, utilities’ refusal to adopt sound energy alternatives, industrial development and highway construction at the expense of public health, intensive livestock operations’ effects on agriculture and the environment, and huge waste dumps.”
When asked what she personally found so dangerous about fracking, Girolami says that her two biggest issues come from the health risks and how quickly the practice of fracking is being accepted despite a lack of real preparatory analysis.
“Fracking so bad because it’s so polluting,” says Girolami. “It’s so polluting to ground water, surface water, air, air health, and it’s been so rushed. So rushed we haven’t done a health study, we’ve done no air rules. The Energy and Mining Commission has been meeting for two years, but there are big gaps in the rules they put together.”
Vick reminds of the recent legislation created that states it is a misdemeanor to disclose what chemicals are used for digging. She says that this is not how the community should be treated when it comes to this form of resource gathering.
“The community has the right to know what is being injected into the ground under their feet,” says Vick. “Our organization just passed a resolution on chemical disclosure that we hope to share with other folks, but my feeling is that the reason they don’t want people to know is because of that potential liability.”
***Listen to the full interview here***
For more on the Blue Ridge Environmental Defense League, click here.http://chapelboro.com/news/health/anti-fracking-response-interview/
This is the conclusion of a three-part series inspired by the North Carolina General Assembly’s decision to make the disclosure of the chemicals used in fracking a crime here in the Tar Heel State, purportedly to protect the trade secrets of the drilling companies. In Part I, I reviewed why I do not believe that the identities of these chemicals qualify as trade secrets. In Part II, I gave my opinion on what I believe to be the actual motivations for the legislation. This week, I want to direct your attention to an important part of the fracking process that gets very little media attention: the fate of the water and chemicals that are extracted from the well after the underground rocks have been broken.
Before we proceed, let’s quickly review the fracking process. First, a drilling company locates what it believes to be an underground deposit of oil and/or gas contained within non-porous rock. (If the rock was porous, fracking would not be necessary.) A vertical hole is drilled straight down to the depth of the deposit and then multiple horizontal holes are drilled out from the bottom of the vertical hole. Next a mixture of water, sand, and chemicals is pumped into the horizontal holes where high temperatures and pressures combine to fracture the rocks. Approximately 40% of the water and chemicals are pumped back out of the well to the surface, while the sand and the remainder of the liquids stay underground forever. Once this is accomplished, extraction of oil or gas from the well can commence.
Hundreds of different chemicals are used in the fracking process, many of which are toxic and/or carcinogenic. (For a full list of the typical chemicals used in fracking and their functions, please open this link.) Much of the concern about fracking stems from the fear that these toxic substances could migrate underground from the zone where the fracking occurred into underground aquifers which are utilized for drinking water and/or agriculture. This risk is valid, and there have been a number of documented cases where this appears to have occurred, with a notable case in Pavillion, Wyoming. (1)
But what about the 40% of the fracking liquids which are pumped out of the well? Where do they go, and what sort of risks do they present?
When water is extracted from the well after the fracking process, it contains a portion of the chemicals it started with, plus others which are absorbed from the underground rock formations, particularly hydrocarbons and toxic heavy metals. Depending on the location of the well, some of the heavy metals may be radioactive. From here forward, I’ll refer to the mixture of liquids extracted from the well as fracking wastewater.
When fracking wastewater is extracted from the well, it is usually first collected in a temporary, open pond. Both of the adjectives describing the ponds should concern you. Since the ponds are intended to be temporary, there is an incentive to make them just sturdy enough to do the job, with little safety margin for the unexpected. In addition, open ponds often overflow in heavy rains. Spills of fracking wastewater from a pond have a far easier path to pollute our drinking water sources than the wastewater left underground.
Once the wastewater is contained in the pond, the drilling company needs to figure out what to do with it. Given that it is called wastewater, people often think we could send it to a municipal wastewater treatment plant. We can’t. Municipal wastewater treatment plants remove solids with filtration and then clean the dissolved organic material (poop) by letting bacteria eat it. Fracking wastewater includes many dissolved chemicals which bacteria cannot eat.
The fracking wastewater can be cleaned using an expensive, energy-intensive process, the details of which I will omit for the sake of brevity. Given that there are millions of gallons of wastewater produced from each well, the drilling companies are always on the look-out for less expensive solutions for its disposal. A common, less expensive approach is to inject the wastewater into either an old oil or gas well or into a new well drilled explicitly for wastewater disposal.
In Oklahoma, where fracking began in earnest in 2008, there are now thousands of fracked wells, and wastewater injection is a very common disposal technique. The combination of shattering the underground rock by fracking and pumping wastewater into disposal wells has had a dramatic effect on seismic activity. The graph below shows the absolutely stunning increase in the incidence of earthquakes registering 3.0 or higher on the Richter Scale since fracking began in Oklahoma, from a historical rate of one or two a year up to the current level of one or two a day! The geographic correspondence between the earthquakes and the drilling activities (they are in precisely the same places) is nearly exact, leaving very little doubt that fracking and the injection of the wastewater are the cause.
The implications for North Carolina are clear. Given that fracking in NC appears to be inevitable, we need to do our best to ensure that the regulations give adequate attention to the wastewater handling. Among other things, the wastewater storage ponds must be well constructed and account for the possibility of heavy rains. The drilling companies should be required to treat the wastewater in a thorough and responsible manner rather than simply injecting it back into the ground. Otherwise our experience with fracking is likely to be particularly unpleasant.
Have a comment or question? Use the interface below or send me an email to email@example.com. Think that this column includes important points that others should consider? Send out a link on Facebook or Twitter. Also, please note that I am taking a rare vacation from writing. This will be the last Common Science until June 29th.
(1) Reports in the general media will usually cite higher rates of the incidence of drinking water contamination from fracking than you will see in my columns. I’d like to explain why. The vast majority of fracking-related water contamination events reported in the media are situations where the water has a higher than normal level of methane (the primary component of natural gas.) While I understand the rationale for including them, I do not.
First of all, since methane is everywhere, it is present at some level in all drinking water. Furthermore, it is biologically inert. So even if you are ingesting some in your drinking water, you body will not interact with it in any way. Therefore, it can’t hurt you.
Furthermore, since methane is not very soluble in water, your maximum exposure is limited. Due to this low solubility, I would like to note that I feel strongly that the famous scene in the movie Gasland where a man lights his kitchen faucet on fire was a fake. As far as I can tell, it is thermodynamically impossible.
I only count situations where a chemical added to the fracking process, many of which are quite harmful, ends up in drinking water. These situations have been less frequent than methane contamination, but they are far more troubling.http://chapelboro.com/columns/common-science/fracking-gag-rule-part-iii-wastewater/
As I write this column, Republicans in the North Carolina General Assembly (NCGA) are fast tracking a new law which makes it a Class 1 felony to disclose the identities of chemicals used in fracking here in the Tar Heel State. The purported rationale for this law is that identities of these chemicals are closely guarded and valuable trade secrets for the drilling companies. In Part I of this series, I reviewed how and why chemicals are used in the fracking process ,and why I think the suggestion that the identities of the chemicals used represent valuable trade secrets is absurd.
If I am correct that the legislation is not really motivated by the need to protect the alleged trade secrets of companies like Halliburton and Schlumberger, what are the actual motivations for the drilling companies to advocate for this law? Below are my opinions.
I believe the oil companies and their lobbyists are pushing this gag rule legislation for four reasons, all of which are related to the use of petroleum distillates in the fracking process. If you want the full story on the use of petroleum distillates in fracking, please read Part I of this series. For the purposes of this column you need to know four things about petroleum distillates:
1. They are a low-value byproduct of the oil refining process.
2. They contain hundreds of different small-to-medium-sized hydrocarbons.
3. They are needed as a co-solvent to allow the other chemicals used in fracking to remain stabilized in the water and sand mixture which is pumped into the wells.
4. They contain small concentrations of known carcinogens.
Reason Number 1: Characterizing Petroleum Distillate is Cumbersome
The composition of petroleum distillates is complex, since they contain hundreds of different chemicals. Furthermore, the composition of the distillates continually changes based on the type of oil being refined as well as on changes in the operating conditions of the refinery. Therefore, if the drilling companies had to disclose the chemicals used in each of their thousands of fracking wells, it would require a lengthy and detailed laboratory analysis accompanied by a substantial amount of paperwork. They could do this work – they just don’t want to.
Reason Number 2: Benzene
All petroleum distillates contain benzene, a widely known and feared carcinogen which can cause leukemia. Public disclosure that a drilling company was injecting benzene into the ground beneath our drinking water aquifers would cause alarm.
The drilling companies could point out, correctly, that the potential exposure from the small amount of benzene used in fracking is significantly lower than the amount of benzene which one routinely inhales while pumping gas. (Benzene is used in gasoline to improve the octane rating, which makes your engine run better.) However, I suspect this sort of argument would fail in the court of public opinion. People would just stop listening after “benzene.”
Reason Number 3: Water Pollution Monitoring
If fracking really does take place in Lee and Moore Counties, government agencies and non-governmental organizations will test for water pollution in nearby streams, lakes, and wells. Since, as I pointed out in Part I, everyone already knows what chemicals are likely to be used in fracking, it will not be difficult to know what to look for.
For example, let’s say the Lee County chapter of the Sierra Club detects hexane in Oldham’s Lake outside of Sanford. If a comprehensive list of the chemicals injected into specific wells was available, then it would be fairly easy to locate the source of the pollution. You, my gentle reader, may think that’s a good idea. It would appear that the drilling companies do not.
Reason Number 4: Free Disposal
Of my four proposed “true reasons” for the gag rule, this last one is the most speculative, but to me, the most interesting. As I have explained, the petroleum distillates used in fracking are a low-value byproduct from oil refining. In fact, their value is so low that it is not really worth the effort and expense to try to sell them as paint thinners or fuel additives. Therefore, if you were an oil refinery owner and operator, you probably wish they would just magically disappear.
When the implementation of fracking took off in the U.S. around the year 2005, it created a new and (if you were a refinery owner) exciting outlet for petroleum distillates. So oil companies who are supplying the distillates to the drilling companies have an incentive to maximize the amount of distillate used in fracking, even if it is more than is required as a co-solvent. To the extent that the amount of petroleum distillate used exceeds the amount necessary as a co-solvent, it represents a kind of free and legal chemical dumping. Without having access to the data on the exact concentrations of the chemicals used in fracking, it is not possible for me to be sure that this is happening. However, the incentives to do it are clear and compelling.
There are so many things wrong about this gag rule, I find it hard to organize my thoughts. So please forgive me for resorting to bullet points:
• The reasons that legislators provide for any law should correspond to the actual reasons for the law. It seems abundantly clear to me that this gag rule law has nothing to do with shielding trade secrets. Rather, it seems clear that it is motivated by some combination of the reasons I listed above. Saying otherwise, as the Republicans are, is deceptive and dishonorable.
• With the exception of vital national security concerns, government should always be as transparent as possible. We all live here, farm here, and drink our water here. If the NCGA is going to allow the injection of chemicals underground, it should require full public disclosure.
• As a citizen of North Carolina, I am not at all comfortable with the NCGA deciding to utilize the criminal justice system to address a civil matter such as alleged financial harm to a corporation from disclosure of purported trade secrets. If any of my readers are versed in the law and policy in this arena, I would very much like to hear from you.
I’ll conclude this series next week with an exploration of an aspect of the fracking process which gets far less attention than it deserves: the fate of the water and chemicals that are pumped out of the well after the fracking process is completed.
Have a comment or question? Use the interface below or send me an email to firstname.lastname@example.org. Think that this column includes important points that others should consider? Send out a link on Facebook or Twitter.http://chapelboro.com/columns/common-science/fracking-gag-rule-part-ii-real-reasons/
Three major, and controversial, decisions have been made in the North Carolina General Assembly this past weekend: the Senate’s new spending plan, teacher pay raises, and the fracking bill.
The Senate has decided upon a new $21.1 billion spending plan for 2014-15 this weekend. Democrats were displeased with how quickly the decision was made, as it allowed for minimal negotiation. They seemed to be in consensus that the Senate was only interested in hearing their own approval, rather than the perspectives of the general public.
As part of this new budget plan, legislators also desire to encourage teachers to give up their tenure in exchange for an 11% raise in pay. Teachers, in response, are disagreeing with the motion as they desire more protection from unfriendly politics that surround schools presently. These raises are also planned to be gathered from cuts that would come from public school spending.
Other states are allegedly not attempting this swap of pay raise for tenure. Democrats agree that this action is not for the benefit of the teacher’s, but more of a cover-up for legislators’ inability to manage money wisely.
The fracking bill, completely supported by the House Republicans, is now on its way to be signed by Gov. Pat McCrory, who is more than ready to help get it passed. While Democrats were clearly unhappy with the bill, they failed to halt the process. Instead, they were able to add a few minor alterations to the bill as compromise before being sent to Gov. McCrory.
Many North Carolinians fear what the fracking might mean for chemicals that could get into well water, as well as how the Senate now seems to have the ability to override local governments in relation to how the fracking will be carried out.
As of now, there seems to be a great deal of controversy with each major decision processed by the General Assembly of North Carolina this past weekend. The uncertainty regarding the decided amount of the budget has some questioning how things are going to get better now. The risky move of raising teachers’ salaries whilst eliminating assistants and tenure is causing a rift of displeasure from educators of North Carolina, and unfavorable fracking plans that may affect local businesses in a way that they are unwilling to comply with the Senate’s decision.http://chapelboro.com/news/local-government/general-assembly-check/
I was in the middle of writing a column about the unique benefits and properties of fertilizer made from seaweed when I got distracted by the North Carolina General Assembly. A Republican-led senate committee has proposed to make it a felony for a citizen to disclose the names of the chemicals used by drilling companies in the hydraulic fracturing (“fracking”) process. The purported rationale is that drilling companies claim that the mixtures of chemicals they use are confidential trade secrets. As I will outline below, this claim borders on the absurd.
I have written about fracking several times in the past. For a thorough review of the technology and potential environmental risks please read my previous column, To Frack or not to Frack. For the purposes of this column, here is a very brief summary of fracking. When companies drill for oil or gas, everything is much easier if the deposits are contained in underground rock structures which are relatively porous. The porosity makes it easy for the oil and gas to move from place to place and thus to be extracted to the surface. As time has passed in the United States and around the world, oil and gas deposits contained in porous rock formations have been significantly depleted and drilling companies have started to exploit deposits which are present in low-porosity formations. To extract the oil and gas from these low-porosity rocks, the rocks must first be broken by fracking.
Fracking involves first drilling a hole straight down to the depth where the oil and/or gas deposits reside and then drilling horizontally through the non-porous rocks. Next, millions of gallons of a mixture of water, sand, and chemicals are pumped into the well. Since the temperature below ground is much higher than the surface, the water expands, which creates incredibly high pressures which then fractures the rock. The sand stays within the rock formation to help keep the smaller fissures created in the fracking process open. About 40% of the water and chemicals used in the process are pumped back out to the surface, while the other 60% remain underground.
The chemicals used in the fracking process have several purposes. A partial list includes:
• preventing the sand from clumping together too soon or too tightly,
• reducing the viscosity of the mixture so that it will flow through small cracks,
• preventing corrosion of the metal pipes used in the well, and
• killing bacteria in the water.
Many of the chemicals used in fracking are not soluble in pure water. If these chemicals can’t be dissolved or at least suspended in the water, the fracking process would not work. Therefore, in order to stabilize the chemicals in the water, it is necessary to add some hydrocarbons to the mixture as a co-solvent. Many of the issues and controversies surrounding the environmental risks of fracking are related to the hydrocarbon co-solvent.
The hydrocarbon co-solvent which is typically used is called petroleum distillate. Without going into a lengthy explanation of how an oil refinery works, petroleum distillate consists of a mixture of small to medium size hydrocarbons which were either present in the oil when it was extracted from the ground or created by “cracking” larger hydrocarbons into smaller ones during the oil refining process. Gasoline, kerosene, and diesel are all examples of petroleum distillates. Petroleum distillates generally contain hundreds of different types of hydrocarbon molecules, including known carcinogens such as benzene.
If you are running an oil refinery and want to maximize profits, you operate the equipment so that you manage to sell most of your petroleum distillate as gasoline, kerosene, or diesel. However, because of the nature of petroleum as well as the limitations in the specifications for products like gasoline, the refinery will end up with some distillate left over, for which there is no good commercial outlet. The refinery may be able to sell a portion of these leftovers as paint thinner, but much of it is effectively just waste. It is this waste distillate which is being used across the country as the co-solvent hydrocarbon for the fracking process.
With that background in mind, let’s first examine the claim that the recipes for these mixtures of fracking chemicals used by the drilling companies represent valuable, proprietary trade secrets. Our first hint that this claim is suspect stems from the fact that the technology involved in suspending sand in water and keeping pipes from corroding is neither novel nor complicated. There is certainly some art in calibrating the concentrations of the chemicals to adjust to local geology, but no esoteric or novel science is involved.
Our second hint is that the drilling companies do not invent or own the recipes for the fracking chemicals themselves. Rather, they rely on the one of the four large U.S. oil field services companies – Schlumberger, Halliburton, Flour or Baker-Hughes – who dominate the market. To the extent that a rationale might exist for maintaining trade secrets on fracking chemicals, it would presumably stem from protecting these four companies from one another. Given that all of these companies have been working on the same projects in the same places for decades, they already know exactly what each other are doing. Therefore, the suggestion that a citizen of North Carolina could cause financial harm to Halliburton by disclosing which anti-corrosive chemicals it is using does not pass the smell test.
So if Halliburton and the other companies don’t really need this to be protected by the North Carolina General Assembly, what is the real purpose of this proposed gag rule? I will give you my thoughts on that next week in Part II of this series. The week after in Part III, I will conclude the series by addressing the fate of the 40% of the water and chemicals which are pumped back up to the surface during the fracking process. It seems that the seaweed column will just have to wait.
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In last week’s column, The Case of the Missing Propane, I explained how the widespread use of hydraulic fracturing (fracking) of shale oil deposits since 2008 has led to a 30% increase in the production of crude petroleum in the United States. While that statistic makes for snappy headlines, it is not particularly meaningful to the overall world oil supply or the phenomenon known as Peak Oil.
If you are not familiar with Peak Oil, I published a column in June of 2011 called Peak Oil in Five Paragraphs or Less. Here are the key points:
• Peak Oil refers to the time at which we reach the global maximum rate of oil production, which is followed by decades of declining rates of production.
• Due to oil’s pivotal role as a transportation fuel and (as I explained in Everything Comes from Oil) the key raw material for most consumer goods, the global economy can only grow if oil supply continues to grow.
• In order to keep producing more and more oil, you must keep discovering more and more and more. This is not possible. Eventually you are exhausting oil fields at a rate faster than the new ones can be discovered.
• The global peak for conventional oil sources occurred in approximately 2005, requiring us to turn to unconventional sources such as shale oil and oil sands. These sources are expensive to exploit and will not last for very long.
• The economic disruptions cause by the impending oil supply constraints will be very challenging for the global community.
The graph below was the key feature of Peak Oil in Five Paragraphs or Less. This graph is pivotal to understanding both the history and economics of the last century as well as the challenges coming in the next; everyone should be familiar with it. Its peaks and valleys tell stories as varied and interesting as the growth of suburbia in the U.S. and the role of Saudi Arabia in the post World War II era. But I never see this graph in the papers. It’s not hard to understand. As you can see from the bars, the peak year for global oil discovery occurred in 1965, the year before I was born, and has been generally declining ever since. Due to extraordinary efforts by the oil companies, the rate of production has yet to start declining, but as those old fields continue to be exhausted, it will.
Beginning in 2007, you see a small, but temporary, increase in “discoveries” which corresponds to shale oils such as the Bakken Shale in North Dakota. I put discoveries in quotations because shale oil deposits have been known about for decades but were simply not counted as petroleum reserves due to their low quality. The oil sands in Alberta, for which the Keystone XL pipeline is intended, fall into this same low-grade category.
Before I show you some additional graphs (I love graphs), we need a brief aside on definitions and sources. The data I use below is from the U.S. Energy Information Administration (EIA) and is, therefore, reliable for past data. Different sources define “oil” differently, which can cause confusion. Some, such as this column, restrict the definition of oil to crude petroleum – think gushers from old movies. Other sources add in liquids that are collected during natural gas refining – we discussed those last week – as well as biofuels, resulting in larger totals.
The graph below shows U.S. crude petroleum production in millions of barrels a day since 1980. From 1980 through 2008, there was a steady decline from 9 million to 5 million barrels a day. In 2008, fracking of shale oil began in earnest, which has increased U.S. petroleum production from a low of 5 million to 6.6 million barrels a day, an increase of 30%.
Extracting petroleum from shale formations is an expensive business. After you go through all the effort and expense to drill downward and then horizontally, and break up the rock below with high pressure fluids (fracking), the production from the well falls off by an average of 65% during the first year. Therefore, in order to keep production going, you’ve got to keep drilling and drilling and drilling. In 2011, 16,000 fracking wells were drilled in the U.S. In 2012, it was 19,000.
While doing the research for this column, I decided to have a look at the Bakken Shale Field formation, which spans the North Dakota-Montana border just south of Canada, on Google Earth. I could not get a nice looking picture for you, but it is somewhat fascinating to see. If you use the satellite map feature, follow the existing rural roads, then look for secondary dirt roads which lead to dirt rectangles. Each rectangle will contain a well with a pump on top, four tanks for collecting the oil, and some other equipment. You generally will not find any people or vehicles, because these units run automatically. As you pan around, you can find them by the hundreds.
The increase in petroleum production in the U.S. has not provided any meaningful relief from high gasoline prices, which remain steadfastly above $3.00 per gallon. There are two main reasons for this: petroleum is a global commodity (more on that below) and fracking is an expensive technique. Consider that in 2004, oil sold for about $40 per barrel. The break-even price for a barrel of oil produced from fracking is $80.
The graph below shows world crude petroleum production along with the same data I showed for the U.S. in the previous graph. As you can see, petroleum production in the U.S. is only a small fraction of the global total. Therefore, the 30% increase in U.S. production has only increased the global supply by two percent. A two percent increase in global supply, especially an expensive supply, is not sufficient to result in a reduction in U.S. fuel prices.
So where does this leave us? Overall global supply of petroleum is being maintained near 76 million barrels a day based on the extraordinary efforts to extract unconventional oils. Sometime between now and 2025, the supply will begin to decline and cause social and economic dislocations. As we continue to exploit the unconventional sources during this time, carbon dioxide concentration in the atmosphere will grow from 400 to 450 parts per million, causing even more dramatic changes in our weather patterns and challenging our ability produce enough food for eight billion people. Dealing with these parallel challenges will be the defining features of the 21 century.
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Over the past few weeks, I have seen many stories about propane shortages in the United States. As a result of these shortages, prices for propane have nearly doubled from around $2.20 per gallon at the end of last year to over $4.00 per gallon this week. This situation struck me as quite odd. We should be nearly drowning in propane at the moment. So I decided to try to figure out what was going on.
As usual, let’s start with the background. Propane is a small, simple hydrocarbon with the chemical formula C3H8. At normal temperatures and pressures, propane is a gas. By applying a modest amount of pressure you can induce it to liquefy, which is what comes in the propane tank you may be using for the grill on the back porch.
Three quarters of propane production in the U.S. comes from the refining of natural gas. The primary component of natural gas is methane (CH4). Mixed in with the methane are larger hydrocarbons such as ethane (C2H6), propane and butane (C4H10). Before natural gas can be put through a pipeline (the only economical way that it can be transported long distances), most of the propane and butane must be removed, thus resulting in most of our supply of propane and butane. Butane is what is used in most cigarette lighters.
The other 25% of propane production in the U.S. comes from petroleum refining. In order to make fuels such as gasoline and diesel from crude petroleum, there is a processing step called cracking. Cracking is just what it sounds like, the breaking up of larger hydrocarbon molecules into smaller ones. Some of these smaller molecules are propane, resulting in the rest of our propane supply.
Propane is used almost exclusively as a fuel for heating. The breakdown of propane consumption in the U.S. is shown below:
Industrial heating 50%
Residential/recreational heating 42%
Agricultural (e.g. drying grain) 7%
Due to the implementation of hydraulic fracturing (“fracking”) as a drilling technology, production rates of natural gas and petroleum in the U.S. have both increased approximately 15-20% since 2008. Therefore, production of propane, which is recovered from both of these sources, has also increased by this amount.
The increase in supply has resulted in a dramatic decrease in the price of refined natural gas, which has inspired power companies all across the country to convert from coal to natural gas for fuel. So I set about trying to determine how there could be a shortage of propane and a surplus of refined natural gas at the same time.
I checked U.S. propane consumption to see if increases in demand were outpacing the large increase in supply. The U.S. Energy Information Administration data shows that propane consumption in both October and November of 2013 was slightly above normal while use in December had fallen back to within the norm. This small increase in demand last fall could have put some strain on supply, but not enough to explain the dramatic price spikes on its own.
Then the likely answer occurred to me. Since natural gas can only be transported in an economically feasible manner via pipeline, nearly all of U.S. production is consumed domestically. Propane gas can easily and economically be compressed to a liquid. Liquids are easy to transport and, thus, easy to export.
That turned out to be the answer to the mystery. In 2008, only 5% of U.S propane production was exported. By 2013, driven in large part by high demand in Asia, the amount exported increased to 20%!
Let’s work the numbers. In 2008, the U.S. produced an average of 1.8 million barrels a day of propane, exporting 0.1 million barrels and leaving 1.7 million for domestic use. By 2013, production had increased 20% to 2.16 million barrels a day, but now 0.43 million of these were exported, leaving just 1.73 million for domestic use. As you can see, essentially all of the production increase since 2008 has been allocated to export.
The consumption of all fuels in the U.S. increased along with the growth of both population and the economy. Therefore, while the 1.7 million barrels a day of propane met demand in 2008 – a year with a weak economy – the 1.73 million barrels a day allocated to domestic use were just barely enough for 2013. As a result, even the minor increase in demand which occurred last fall was enough to cause a large spike in price.
This chain of events which led to the propane shortage this winter warrants some additional reflection and analysis. Consider the following timeline:
• In 2004-2005, natural gas production in the U.S. from traditional extraction technologies was not keeping pace with the demand and resulting in dramatic price increases.
• The high price for natural gas was a primary driver in the dramatic expansion of fracking in the U.S., which significantly increased the supply of natural gas and, thereby, caused a drop in its price.
• Fracking also brought about a large increase in propane supply.
• Because drilling companies are compelled to maximize near-term shareholder return, the surplus propane is being exported.
• Ensuring that U.S. citizens benefit from the increased propane supply in the form of lower prices stemming from surplus domestic supply would require the type of government regulation of the energy sector which is vociferously opposed by Republicans.
• Most homes which use propane for home heating and kitchen cooking, the people who are most harmed by the price increases, are located in rural areas.
• Rural areas tend to steadfastly vote Republican.
When the Republican politicians who represent those harmed by these price increases are pressed to provide an explanation for why their constituents’ heating bills have doubled, they tend to offer a list of talking points about excess government regulation. They offer the libertarian vision that if only the oil companies were free of government constraints, all would be well. As I laid out for you above, this explanation is demonstrably false.
When I ran unsuccessfully for a seat on the CHCCS Board of Education in 2005, I campaigned on my commitment to data-based decision making. That phrase lacks “zing,” which may explain why engineers make for mediocre political candidates. To me, though, the current domestic propane price increase is a perfect example of the need for data-based governance. The data tells us that the propane shortage in the U.S. is the result of the rise in exports. Our lawmakers should make policy based on this data to ensure that American citizens reap the benefits of increased American energy production. For those of you I confused back in 2005, this is what I meant.
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