Earthquakes in Ohio

I love you, Rachel Maddow. But I need to take exception to a thing you said, as much as it pains me.

Visit msnbc.com for breaking news, world news, and news about the economy

It's a long clip, and the point in question is sort of interspersed through it. Basically Rachel says that the earthquakes in Ohio were caused by fracking. And that this is somehow a surprise.

Now, this may be a nitpicky complaint, but I'm a nerd and it's my purview to get nitpicky about things.

The earthquakes in Ohio were not directly caused by fracking. they were caused by waste water injection. While Rachel does say this at one point in the clip, for the most part this gets shortened down to the earthquakes being caused by fracking.

In this case, the best you could come up with is an indirect cause, since without the hydraulic fracturing, there wouldn't be a lot of fluid that needed to be put down the disposal well. But frankly, if you want to be accurate, you have to say that the earthquakes were caused by improper waste water disposal.

And you know what? This is not a new thing. Deep waste water disposal wells in Colorado in the late 60s and early 70s caused earthquakes as well. If there are faults in the area, waste water can get in to them and lubricate them. Or if the well is over pressured, that can change the local stress field and get things to shift around.

As I said, I know that this may seem like hair splitting, but it bugs me to no end to hear the waste water disposal issue being conflated with the actual process of hydraulic fracturing. It's sloppy. If nothing else, waste water disposal wells are not a new concept, and even without hydraulic fracturing they still get drilled and used because normal oil production often entails a large water cut (ancient salt water coming out with the oil) and that water gets re-injected in disposal wells.

It's another question to ask if hydraulic fracturing itself causes earthquakes. Likely yes in summary, and here's a nice recent example from Oklahoma. Though the point in both of these places is really that any induced seismicity is less than a magnitude of 3.0, too small for us to actually feel.

Whether or not this is cause for worry is a whole issue on itself. We can also cause seismic activity by pulling a lot of water out of aquifers and thus cause compaction issues. (Or pulling a lot of oil out of reservoirs and causing compaction there.) While the effect is the same (man-made earthquakes), the causes deserve to be addressed with accuracy.

Fracking on the SGU

The Skeptic's Guide to the Universe this week (episode #346) has an interview with Gordon Maupin, about fracking. I think Mr. Maupin was very reasonable and it's definitely a good interview to hear for a calm, measured take on the topic.

It would have been nice to hear more discussion of the geological issues, but Mr. Maupin also isn't a geologist so that's likely why he wanted to address it mostly as a policy issue and just stick to move of an overview with where the science is at. (At the moment inconclusive with a large side of surface contamination being the more likely culprit.)

Hopefully once the EPA finishes their study, maybe they'll interview a geologist...

Two Earth Science Items

Everyone should read this post. It's by Dr. Bailles, one of the co-discoverers of the so-called "diamond planet" that the media was having squee spasms about recently. He pointedly notes that his discovery wouldn't have been at all gleefully received if he was, say, a climate scientist, despite the fact that the scientific process and peer review is the same.

Which I think is a really good point. Everyone loves hearing about awesome astronomy things, and you never see the media seeking "balance." And by "balance," I mean, "finding a dissenting voice on the fringe of the science to provide the illusion of fairness when, in fact, the dissenting voice is the minority and has often failed to address the criticism of his or her peers."

But, you know, "balance" is way easier to type.

And Brian Dunning of Skeptoid just put an episode out about fracking. I did a couple of posts about that myself, almost two years ago. Generally, I think Brian did a good job, and the episode is worth a listen. His ending point is excellent - it's important to separate the science from how much you loathe Halliburton, for example.

The only complaint I've got is for part of the episode he refers to natural gas drilling as "mining" for some reason I can't fathom, and even refers to wells as "mines" in a couple of instances. That started driving me a little crazy after a while. But then he uses "wells" and "drilling" in other parts of the podcast, so I'm not sure what's going on with the vocabulary choice.

Also, I would have liked to hear Brian mention that fracking fluid is exempt from the Safe Drinking Water Act, due to a 2005 amendment. This is something I still personally think needs to be changed due to the possibility of surface contamination. There are sites like FracFocus, which sounds like it's built on voluntary disclosure. As far as I know there's no other federal requirement of disclosure (please, correct me if I'm wrong) though it sounds like a lot of states have laws now. Ultimately, your mileage may vary depending upon how evil you may think the various oil companies are, but I do have my doubts that fluid additives would be disclosed without a legal requirement; if nothing else, a lot of the additives are proprietary.

Anyway, good job, Brian!

Hydrocarbon Formation at Depth

I think this got mentioned on this week's Skeptic's Guide to the Universe in the science or fiction. I thought it might be the fiction, but wasn't all that surprised when it turned out to be science:

Hydrocarbons in the deep earth (press release...?)
Stability of hydrocarbons at deep Earth pressures and temperatures (PNAS article)

And this of course ties back in to my previous linking and random ruminations about abiotic oil.

Mostly, I think this article is interesting, but not something explosive in terms of what we know about the formation of petroleum. I actually found this PNAS article via a post with the faceplam-worthy title "Oil and Gas Forever?"¹ on the website of The Global Warming Policy Foundation - which is apparently supposed to be "devoted to challenging conventional wisdom about climate change." I do think that if you just check the front page of the site (The GWPF's, not the Daily Mail's), the axe they're grinding is evident. Though maybe it is with the Daily Mail's too, I wouldn't know.

But I digress.

Despite the murky chain of links I followed to find the little PNAS article, I think it's interesting. And will probably be horribly misused by excited people who think "Oil and Gas Forever" sounds like a lovely concept in general. The article itself is about computer simulations run to see if methane could form in to longer hydrocarbon chains at deep pressures and temperatures, and according to the simulations, the answer is yes. Which can be considered a point in the camp of abiogenic oil, but I would add the following cautions:

1) Whether long hydrocarbons can form abiogenically or not, that doesn't in any way mean that all hydrocarbons - or even the majority - form in that way. Please see the bit about kerogens in my previous post.

2) This doesn't really address any of the other questions important to developing hydrocarbons, such as: What's the migration path, and how long does it take to get there? (And many more...)

3) It's also not necessarily a realistic simulation. Quoting the first article:

"Our simulation study shows that methane molecules fuse to form larger hydrocarbon molecules when exposed to the very high temperatures and pressures of the Earth's upper mantle," Galli said. "We don't say that higher hydrocarbons actually occur under the realistic 'dirty' Earth mantle conditions, but we say that the pressures and temperatures alone are right for it to happen."

Emphasis mine. So, like much science that gets slapped with melodramatic headlines, this is more of a, "Huh, that's interesting," than anything else.




1 - Actually, it's not what you'd imagine out of an article with that title... it's just the LLNL press release, and a C&P from a blog post that also pretty much emphasizes that there's not really evidence for this being a major source of hydrocarbons, but that this is just sort of interesting.

Abiotic/Abiogenic Oil

You know, the stuff I squeeze out of people who ask me what abiotic oil is on Twitter.

Today, shortly after I admitted (gasp) to being a geologist, one of the guys on my judging team asked me about abiotic oil, saying that "there's been some study in Russia about this." Which I hadn't heard about, but he then said that it was a recent thing.

To the best of my knowledge, abiotic oil is a fairly laughable theory. But I decided to do some googling around, just so I don't get caught off guard by this again.

The first post that I find via google is from FreeEnergyNews.com, which gives me a tingle of apprehension to begin with, just from the website name. Abiotic Oil: This post has a bunch of links for stories from WorldNet Daily, which I'm more familiar with as WingNut Daily, insert logical fallacy here (possibly poisoning the well?). It also posts links to two books from an author whose name I recognize, Thomas Gold. And my recognition of his name comes from this mention of him at the Oil Drum, which is not terribly complimentary. Thomas Gold was also an astrophysicist, not a petroleum geologist.

Now, the post over at the Oil Drum brings up one example where people got all excited about oil being abiotic because OMG IT'S COMING OUT OF BEDROCK, when the facts really looked more like it was oil migrating through faulted horst blocks of the bedrock, since tectonics had partially shifted source rocks so they were under the basement rock in some places. This conclusion comes from this AAPG article, and I will say that AAPG is a professional organization of petroleum geologists and puts out several trusted publications, including the one this article appeared in (Explorer), so I'm going to take their word for it.

However, the "abiotic" oil of Vietnam is not what I'm after here, rather I'm looking for Russia in particular. By adding Russia to my search, I came up with some interesting sites:

An introduction to the modern petroleum science, and to the Russian-Ukrainian theory of deep, abiotic petroleum origins: I think this pretty much outlines the theory, and is in favor of it. As an amusing aside, there's a link to a discussion of plagiarism of the theory. Specifically Thomas Gold plagiarizing the theory from Russian scientists.

One of the sections in the Russian-Ukrainian theory post talks about refuting a biotic origin of oil. While at this point I could see trying to find some wiggle room to allow for both biotic and abiotic oil, but trying to claim that no oil is biotic makes little sense. As just one example, one thing we look for when exploring possible oil sources are kerogens, which come in different types (dependent upon original depositional environment) and release oil when sufficiently cooked. Trying to take kerogens out of the equation (or claiming they're not organically sourced) really flies in the face of a lot of well-established science.

I will also note that going on the theory that oil comes from sedimentary source rocks (where you find those kerogens) has proved to be extremely predictive in oil exploration. Which is a good sign for oil coming from dead critters.

On the other side, a post at FromTheWilderness.com examines many of the fields considered to be "abiotic" proof, and finds them wanting. This post also has found a special place in my heart because of this:

While everyone is free to form his or her own opinion, when people start talking about a conspiracy of scientists to cover up the supposed abiotic origin of oil, then all an honest scientist can do is to shrug her or his shoulders and say that he or she is not aware of any such conspiracy. In fact, such a contention makes numerous logical errors; based on the logical fallacies listed at http://www.nizkor.org/features/fallacies/index.html, I can count at least 17 errors of logic frequently made by those who argue that the biological origin of oil is a conspiracy. Such errors of logic are the province of a politician, not a scientist.

Back to the Oil Drum post, they recommend reading Richard Heinberg's The "Abiotic Oil" Controversy, which I wholeheartedly recommend as well. Heinberg makes a very well-thought out, reasonable argument, and here's the summation of his take-home point:

There is no way to conclusively prove that no petroleum is of abiotic origin. Science is an ongoing search for truth, and theories are continually being altered or scrapped as new evidence appears. However, the assertion that all oil is abiotic requires extraordinary support, because it must overcome abundant evidence, already cited, to tie specific oil accumulations to specific biological origins through a chain of well-understood processes that have been demonstrated, in principle, under laboratory conditions.

I don't think it's possible to, in detail, refute every claim of abiotic oil genesis. Because if nothing else, we don't know everything there is to know about how most oil is generated, let alone how all of it is generated. And Heinberg makes another good point - even if we eventually reach the conclusion that some hydrocarbons are generated abiotically, this does not really change the energy crisis our dependence on fossil fuels is causing. He says:

What if oil were in fact virtually inexhaustible—would this be good news? Not in my view. It is my opinion that the discovery of oil was the greatest tragedy (in terms of its long-term consequences) in human history. Finding a limitless supply of oil might forestall nasty price increases and catastrophic withdrawal symptoms, but it would only exacerbate all of the other problems that flow from oil dependency—our use of it to accelerate the extraction of all other resources, the venting of CO2 into the atmosphere, and related problems such as loss of biodiversity. Oil depletion is bad news, but it is no worse than that of oil abundance.

To a certain extent, I think the attraction of the abiotic theory is that it means people can ignore the thought that we might some day (some very soon day) effectively run out of oil. But whether we can run out of oil or not changes nothing about the environmental damage we are causing by recklessly burning a natural resource that really deserves to be treated with more care.

The Pelican in the Room

I am getting increasingly worried about the Macondo well's continuing shut-in state, not to mention the way BP and Admiral Allen seem to be bickering about it. I guess the good news is that the pressure has built to a reasonable level and has pretty much parked there. That's certainly better than the alternative¹. And to a certain extent, I can understand why what was supposed to be a pressure test has been extended for days to keeping the well shut in. Because it is preferable to allowing the well to continue to flow into the Gulf.

However.

BP's making noise about wanting to try another surface kill. I suppose because the last one went so well. Now, one point in favor of this is that they've got the well actually shut in, so there's at least some integrity to the well cap now. But I'm with Bob Cavnar; I'm worried about the continuing integrity of of the casing and the flex joint², and I'm also worried about the integrity of the formations. There have been concerns since the beginning about casing damage that could allow oil/drilling fluid into the surrounding formations, which could lead to failure, fracturing, and give the oil a new pathway into the open water. This hasn't happened yet, but it very well could, and with no warning. And, now that the relief well is getting close enough to completion to give us a little hope, that kind of failure could needlessly complicate those efforts as well.

If you've ever watched the movie True Lies, think about the scene where the terrorists are driving along the highway across the Florida keys, and the bridge basically gets blown up around them. One of the trucks ends up teetering between staying on the road and falling off into the ocean. The terrorists try to creep toward the back of the truck, hoping to get it to sway back onto the highway. Then a bird (a pelican, I think) lands on the hood and they all go tumbling into the drink.

That sort of farcical balance, teetering between safety and disaster, is what this is making me think of, and BP's inexplicable maneuvering is the pelican in this equation.

With the new cap on the well, they've got four good fittings they could hook in to for the purposes of pumping oil. One excuse for not having done that yet is that one of the risers still needs to be completed, and I believe that one or two of the vessels they would be using aren't there yet. (And of course, constant weather worries.) But what about the vessels and risers already on site? As far as I know (again, geologist, not engineering expert) they ought to be able to just retrieve oil from a couple of the valves and not all of them. They should be able to just take whatever capacity the vessels on site have, which would also keep the well at a lower pressure even if they're not taking the full flow. Why are the pushing the pressure on the well by keeping it shut in if they're worried about the flex joint failing? Why are they looking at a plan that might cause catastrophic failure with the relief well so close to completion? And so on. Unfortunately, I'm not in full possession of the facts, and through no fault of my own; there's a lot of detail that BP is keeping to itself.

I'm starting to fall into the paranoid camp that thinks BP is fighting to keep the well shut in and even pushing for the inexplicable attempt at a static kill because that will prevent truly accurate measurements of the well flow. Since, after all, knowing how much the well can flow at would give a pretty accurate way to measure just how much oil has gone into the Gulf, which is important since fines are charged per barrel - and fees for removal of oil from the lease are also charged per barrel.

It would also be easier for me to dismiss my growing sense of paranoia as misplaced suspicion if it weren't for the fact that this company has already shown a blatant disregard for safety in the interest of savings/profit. BP was aware of the leak in the BOP's control pod for months, and did not see fit to have it fixed. They didn't bother to run a cement bond log³. They didn't conduct a circulation test to see if there was gas in the wellbore. And so on, and so on, an infuriating list that just gets longer and longer the more times BP is called to testify.

BP killed eleven people because they thought the savings were worth the risk. Which is an easy enough decision, I suppose, when you're making it from hundreds of miles away from the drilling rig. BP has put a knife in the heart of the Gulf of Mexico's ecosystem because they thought the savings were worth the risk. BP destroyed the livelihoods of thousands because they thought the savings were worth the risk. No one set out to kill eleven people or damage an ecosystem or destroy the livelihoods of people; but all of these things add up to show a disregard for risk, where the people making the decision about that risk are not the ones that will bear the brunt of the damage if the odds turn sour.

So how paranoid am I actually being, if I find it a reasonable conclusion that they just might be willing to risk exacerbating this heartbreaking situation because it could get them out of some fines? It might be worth the risk. At this point we're all just teetering at the edge of disaster and waiting to see where BP lands.



1 - As in, constant low pressure or a sudden drop in pressure, which would basically indicate that the oil's found a different way to escape the well.

2 - Mr. Cavnar provides a more technical discussion of that issue here. The problem is, none of us armchair quarterbacks knows precisely what fittings/etc are being used, and no one's bothering to share that information.

3 - This is basically a sonic assessment to see if there's cement fully surrounding the casing, which lets you know if the cementing worked properly. Logs usually cost by the foot, so running a log through the entire 15,000 foot length of this well would be a costly proposition. In the past, I've seen different types of logs (for a cement bond log you really have to run the whole thing) that companies have tried to save on by only running them for sections of the well, a couple hundred feet at a time. As a geologist, I find this practice very annoying.

It takes WEEKS to drill 40 feet?

On Countdown last night, Keith Olberman reported that the relief well is 40 feet away from the well that's blown out, and it's expected to take several more weeks to reach it. I thought I'd clarify this, since it may be a little confusing as to why it is going to take several weeks to drill 40 feet.

Per USA Today the relief well is aimed for a point 18,000 feet deep. From the somewhat nonspecific language of the news article, I'm assuming that the 18,000 feet is the subsea¹. This means that the actual drill string for the well will likely be significantly longer than 18,000 feet, since it's being drilled directionally and is thus not the shortest possible distance from the point they're aiming for.

My knowledge mostly relates to how wells are drilled on land, but as far as I know, the principle is the same for offshore drilling. Basically, the actually drill bit is at the end of the drill string, which stretches the length from the rig floor to wherever the bit happens to be at the time. The drill string is effectively a long, long pipe through which the bit can be powered and drilling fluid (mud) can be circulated.

Drill string is, as you can imagine, not just one insanely long pipe. It's made out of joint after joint after joint of pipe. This pipe normally comes in lengths between 30 and 45 feet. So basically, when you're drilling you start with, say, a 45 foot length of pipe. You drill down 45 feet until that pipe is basically at the floor of the rig, then you add another 45 foot length of pipe, then drill down more. And so on. And so on.

The sectional nature of drill pipe is important in this case because as drill string is pulled from the hole, you also have to break it off a section at a time and stack the pipe on the racks. This process can be done fairly efficiently for what it is, but that doesn't quite get around the fact that when you have to pull an 18,000+ foot drill string out of a hole 45 (or whatever) feet at a time, it's not exactly a speedy process.

And that is, in fact, what's having to be done, at pretty regular intervals. As close as the relief well is, they really don't want to miss the Macondo's² pipe, and they're effectively attempting to locate something a bit smaller than a dinner plate. Directional surveys do have error attached to them, so they don't have a precise enough location on the well they're trying to hit to just drill blindly.

So basically what is happening at this point is that the relief well is drilling a little bit (maybe a foot or so, I don't know for certain) and then they're pulling up the entire (18,000+ foot) drill string so they can put a magnetic tool down the wellbore to check the location of the Macondo's pipe. Then they pull up the magnetic tool, put all 18,000+ feet of the drill string back down and drill a little more.

I think "excruciating" is a fair way to describe this process. But with the care that's taken, there will hopefully be a very good chance of hitting the blown out well on the first try, which is the really important thing. Playing fast and loose is certainly part of what caused this issue; hopefully some care and precision will get the Macondo killed finally.

Also, I'll add that around the time the relief wells started drilling, we had a company meeting. I didn't end up attending, but my husband did and reported what had been said. It was mostly one of the VPs passing on information about the disaster. One of the things he said is that THE best directional drilling engineer in the business is at the helm of the relief well. So here's hoping.


ETA: I found this video released by BP³ explaining (with animations) the drilling process for the relief wells. The narration isn't exactly scintillating, but I think the animation can really help you visualize the process. I'll admit, the thing I found most interesting was the enormous range in casing sizes that they've had to set. Casing gets set in layers; I've never seen this many layers, but then again I've never worked on a well at a depth of more than 10,000 feet.

Note: In the video, they refer to "MD." That stands for "measured depth," which is the length drilled. Measured Depth is normally not the same as Subsea Depth, since it's really a measure of wellbore length rather than a quantification of depth below sea level. In this case, they mention a 13,000 foot measured depth, which may seem a little confusing. They're talking about 13,000 feet drilled and not counting the additional footage that it takes just to get from the drilling platform at the ocean surface to the ocean floor, which is approximately 5,000 feet.



1 - Depth below sea level as measured in a line perpendicular to the surface of the sea.

2 - The proper name of our favorite underwater oil "volcano."

3 - I consider this video propaganda-free, since it's a good representation of the drilling process and at no point does the boring narrator compare directional drilling to "a graceful dive into the Earth's hallowed seas of rock" or some shit like that.

Hope and Disappointment

I made it my business to listen to the President's Oval Office speech from last night. I found it to be an intensely disappointing experience.

From where I stand, he had the opportunity to really strongly push the country in a new direction, particularly in calling for new energy policy. While he did say that new policy was needed - and at least he also gave a shout out to the need for stricter regulation - he didn't present any kind of specific plan. And honestly I think that's what we needed. Give us something, Mr. President - you mentioned the plan you came up with for energy independence as a candidate. Even retreading that would have been preferable to the nothing that we've got. I'm also mystified that he brought up the House passing the cap and trade legislation and didn't take the opportunity to put pressure on the Senate for sitting on their hands. (The Senate: where good legislation goes to die.)

Of course, some of the responses to the speech have been pretty ridiculous. Like Sarah Palin telling Bill O'Reilly:

"Otherwise, Bill, we are going to be dropped to our knees and bowing to the Saudis and Venezuela and places like Russia, that will keep producing oil and petroleum products," she said. Then "we will have to ask them to produce for us because we will still be dependent upon these sources of energy."

We're going to have to ask people to produce energy for us anyway; even if we drilled every available reserve tomorrow, the oil wouldn't last long enough to transfer us over to a new energy economy. I'm extremely tired of the lie that domestic drilling will magically fix our "dependence" on "foreign oil." Short of the god of your choice floating down to earth on a cloud made of cotton candy and pissing out an endless river of crude oil for us to dip in to, nothing is going to end our oil dependence until we build ourselves in to a society that no longer feels the need to waste it by setting it on fire.

Also, all the people going on about how the number one priority should be plugging the hole? No shit, really? Are we simply allowed to talk about nothing else until it's plugged? Because standing anxiously around and staring at it, not daring to say another word is not going to make it get capped off any faster. Though I suppose if you're suckling on the teat of the oil companies, that's preferable to using that time to discuss alternative fuel sources.

I was even more disappointed that rather than address the specific policy issues and strike while the iron was hot, so to speak, the President devoted the entire end of his speech to praying. Maybe it's a measure of how helpless he and the people caught directly in the path of this man-made disaster feel, that all they can think of is prayer. But praying isn't going to come up with concrete policy goals that voters can get behind. Praying isn't going to clean up the beaches or stop BP's rather creepy attempts to shut out public observation of the cleanup. God apparently wasn't with the men who died on the drilling rig.

We did this, and we need to fix it. Period. What Rachel said.

But I do disagree with Rachel about one thing. Last night, she said:

In the current setup we have in this country, the oil industry has everything going in their favor. They get all of the gains, all the profits from their incredibly lucrative industry. And the risk is always ours. It's our American beaches that get doused in oil, it's our American marshes that get ruined when something goes wrong, it's our American industries that get destroyed when places where people make their livelihoods get polluted and made toxic.

It's not just our beaches and marshes and livelihoods. As long as our demand for oil remains monstrous, as long as we lionize a business culture where the only responsibility that exists is to make money for the shareholders and damn the social consequences, we own a share in all of these disasters.

You are also a moron.

And by "you," I mean Sarah Palin, which I suppose shouldn't come as a surprise to anyone that hasn't been living in a cave since John McCain made his shark-jumping choice for vice president in 2008.

Extreme deep water drilling is not the preferred choice to meet our country’s energy needs, but your protests and lawsuits and lies about onshore and shallow water drilling have locked up safer areas. It’s catching up with you. The tragic, unprecedented deep water Gulf oil spill proves it.

Sarah? Sarah, let's sit down for a minute. Pull up a seat. I've got some fresh banana bread I just made. Do you prefer milk or coffee?

So let's chat. Look, I know that you've got an agenda, and that you don't like environmentalists. But you're really going off the deep end here. Maybe no one bothered to tell you this, so I'll let you in on a little secret: oil companies want to drill in deep water because it's a way to gain access to a shitload of oil. Full stop. I mean, I'm sure we'd be happily drilling in ANWR too, since there's a nice untapped oil field up there. But that's kind of the point; what any oil company that does exploration wants is to gain access to a field that ideally hasn't been drilled before. Which means there's a lot of oil there for the taking, and the reservoir is still nice and pressurized, and you're not having to wrack your brain to figure out how to squeeze a little more oil out of rocks.

If ANWR had been opened for drilling, this disaster still could have happened, and easily. Why? Because there's a lot of oil on the continental shelf, and the farther you go out and the deeper you drill, the more likely you are to hit something your competitors haven't really tapped in to yet. And I think my point is handily proven by the underwater oil volcano - we're talking a flow of over 20 million barrels in about 40 days, from a single well. That's fairly significant. No oil company in its right mind would leave that kind of potential alone, ANWR or no ANWR.

Let's just consider estimated reserves, shall we?

The USGS did an assessment of ANWR in 2002. If you look at the whole enchilada of land - national land, native lands, and the nearby shallow offshore area - the mean estimate for reserves they came up with was 10.6 billion barrels of oil and 61.4 trillion cubic feet of gas. Let's be generous and say the mean they came up with is right, and eventually that amount of reserves could be proved.

The latest reserves estimate of the Gulf of Mexico I could find on the MMS site was from 2006; the reserve numbers may well be the same today, or possibly larger due to continued exploration. But just with the 2006 numbers, the estimated reserves were:
Proved: 5.22 billion barrels of oil, 16.9 trillion cubic feet of gas (this left after those fields had already produced 15.1 billion barrels of oil and 166.8 trillion cubic feet of gas)
Unproved: 4.44 billion barrels of oil, 8.3 trillion cubic feet of gas
Not available for lease yet: 1.32 billion barrels of oil, 7.7 trillion cubic feet of gas

Looking at those numbers, ANWR is certainly impressive if you count all available land; it may have close to as much oil as the Gulf of Mexico, and a lot more natural gas. (Though considering how ridiculously cheap natural gas is these days, one has to wonder about the benefits to the companies of producing even more of it.) But more importantly, if you think the oil companies would drop their ~10 billion barrels of oil in the Gulf of Mexico so they could have ~10 billion barrels of oil in Alaska instead, I'd like to know what color the sky is on your planet. This is not an either/or situation. I guarantee you that if "safer" (which is very, very debatable) places for drilling like ANWR were opened up tomorrow, there would still be rigs in the Gulf of Mexico unless deepwater drilling was subsequently banned. These are oil companies. They go where the oil is. It's what they do.

Please see also: If You Give a Mouse a Cookie (a cautionary tale)

There are a lot of people to blame for this disaster: BP for its gross negligence, the government for its lack of regulation, the general American public for its unceasing demand for cheap petroleum products. But hippies on bicycles? Get a grip, Sarah. Have some more banana bread.

You, sir, are a moron.

Representative Young, you are a moron.

"This is not an environmental disaster, and I will say that again and again because it is a natural phenomena. Oil has seeped into this ocean for centuries, will continue to do it. During World War II there was over 10 million barrels of oil spilt from ships, and no natural catastrophe. ... We will lose some birds, we will lose some fixed sealife, but overall it will recover."

A Rush Limbaugh-style moron, which is not a distinction many people are able to sink low enough to achieve. So hats off to you, I suppose, in an uncomfortable, "my what a spectacular train wreck that is" sort of why.

Of course, I'm not quite sure if it's actual stupidity that's making these men say such asinine things (and I wouldn't be surprised if they're being parroted by others now) or just flat out intellectual dishonesty.

So when Limbaugh says something like:

Oil is as much a part of nature as water is. … If we didn’t do anything, it would recover.

I'm forced to spend a lot of time wondering if he was actually just born that way, of it he really had to put a lot of time and effort in to becoming that absolutely dishonest.

Oil seeps are, indeed, natural. There are even natural oil seeps in the Gulf of Mexico. But you know, arsenic naturally occurs in food, too, but you wouldn't want a large arsenic spill to occur on your hamburger. The natural oil seeps (per that source) come to an average of 140,000 tons per year, which is around a million barrels of oil. In a year. Spread out through the entire Gulf of Mexico.

If you go with this handy yet incredibly depressing ticker from PBS, we're up to around 21 million barrels already as our best case scenario, in a bit over 40 days. The poison is in the dose, you know. And let's be clear - we would not be getting this sort of oil flow if it weren't for human activities, and as has become increasingly clear, gross human negligence.

What makes me the angriest is really the high-handed assumption that anything we do is no big deal, because mommy Earth will clean it up for us eventually. The absolute disregard for suffering is just breathtaking. The environment might eventually regain its equilibrium after a major spill, though I think you could just as easily argue that it will likely reach a new, different equilibrium instead. But here's the thing. The Earth, the environment, are inanimate entities. They do not give two shits about living things, our incredibly short (on a geological time scale) lives, or any pain or suffering we might feel. It's up to us to care. And considering that collectively we are the cause of that suffering, we damn well should care.

It must be quite easy to not care, to dismiss that suffering and try to squirm around the scary word "disaster" if you make millions of dollars a year being a professional douchebag on the radio, or live quite well as a politician far, far away from the place where the lives of animals both human and non-human are being destroyed.

I've changed my mind about the moron thing. It's far worse than that.

You, sir, are a monster.

Anger and Shame

What BP and the lie of deregulation has wrought.

I am unspeakably angry and upset; worse, I feel helpless all over again. When a single senator can block even the simplest step toward legislating responsibility, what hope is there that the truly necessary measures can be taken?

Regulate and enforce. This has to stop. I wish there was more I could do, but I'm going to start by writing some letters.

Thoughts from a future petroleum geologist

Maybe some of you are tired of seeing this picture already.

You know what? Tough shit.

You should tattoo this picture on the inside of your eyelids. This image should haunt your dreams. Every time you fill up your gas tank, you should think about this. Every time you hear some moronic politician of any stripe utter the meaningless phrase "reduce our dependency on foreign oil," this picture should be what you think about.

I don't make it a secret that I earn my living from the oil industry, and have done so for the past five years. I also don't normally make it a giant talking point. It's quite likely that when I get out of grad school in a couple of years with a Masters' in geology under my belt, I will return to the industry that set me on this academic course and work as a petroleum geologist.

But that doesn't mean I have to support everything that my industry does, or the absolutely stupid attitude that this country has toward oil and natural gas.

And it is stupid. Very, very stupid. Unless you're a believer in abiotic oil¹, you have to come to grips with the realization that oil is an extremely limited natural resource. When it's gone, it's gone. And unless you're pandering, lying, or completely ignorant of how the oil business works, you have to understand that drilling more does nothing to diminish America's oft-cited dependency on "foreign" oil. We're not a country where oil drilling and production is nationalized. When oil is sucked out of formations in America, it doesn't go into a giant barrel marked "For Americans only." While we are a net importer we do export oil. Mostly it's Alaska and West Coast oil going to countries around the Pacific Rim; but the point is, oil produced in America does not automatically belong to us, the American people. And further, increasing the supply of oil is at best only a temporary solution; it does not decrease the demand, and oil - as I've said before - is a limited natural resource.

When I hear any of the slogans - "Drill, baby, drill" or "Drill here, drill now" being the worst offenders - frankly, it makes me want to vomit². It's short-sighted, it's irresponsible, and it displays the sort of willful ignorance and dishonesty that has plagued our country since before the Exxon Valdez disaster. If we're truly worried about the fact that we import massive amounts of oil, that we are gobbling up a limited resource as quickly as it can be drawn from the ground, the solution is not to drill and speed the depletion. The solution is to reduce the demand, period.

So I bet you're wondering now why on Earth I'm working for an oil company, and why I'm considering a career as a petroleum geologist, since I'm apparently so anti-oil.

Part of it is financial, and I'm honest enough to admit that. My years in this industry have been the best of my working adult life. My company treats its people incredibly well, and I find the work very intellectually stimulating.

But more importantly, it is because I'm not anti-oil. I'm anti-stupidity and anti-irresponsibility. And those are the two qualities that have marked the handling of the industry and the public's general reaction to it since... well, ever, I'd say.

I believe that it is possible for oil companies to drill in a responsible manner that limits the environmental impact to almost zero. I believe that risky projects shouldn't be undertaken unless every possible precaution has been taken and the environmental impacts have been thoroughly studied and understood.

I believe that it is the government's job to step in and make certain that happens with strict regulation, monitoring, and enforcement, because frankly I think it's stupid to expect people to monitor themselves when they're in a situation where all profit is private but risk is shared out with the public, willing or no.

I believe it was industry irresponsibility that caused the slow-motion disaster that continues to horrify me every day, and it was also government irresponsibility. And frankly, it was also the irresponsibility of each and every person in America that has bought into the lie that business and industry don't need regulation.

But even more important - and I am going to put this in bold, because if you take nothing else away from this post, I want you to remember this - I believe that oil is an amazing and versatile natural resource that could be used to the general benefit of humanity and it is a crime that we are burning it.




Other posts to read:
An Open Letter To Anyone Who Ever Said "Drill, Baby, Drill"
The Power of a Photograph...




1 - Often referred to as "snake oil" or "horse shit" by most geologists I've ever encountered - and keep in mind that most of my geologists buddies are card-carrying members of AAPG.

2 - And not just because it's often being said by Sarah Palin.

Lusi mud volcano: a drilling disaster

Strongest evidence to date links exploration well to Lusi mud volcano - this is quite the debacle. Obviously, there are safety concerns to be discussed regarding any sort of economic drilling. (Such as the long talk back in December about hydraulic fracturing. I think this one scores extra style points, however. There's something impressive about drilling that's gone so badly wrong that it's created a freaking mud volcano. One that's slowly covering the surrounding area in steaming, awful mud.

The group of scientists has identified five critical drilling errors as the causes of the Lusi mud volcano eruption:

• A significant open hole section with no protective casing
• Overestimation of the pressure the well could tolerate
• After a complete loss of returns, the decision to pull the drill string out of an extremely unstable hole
• Pulling the bit out of the hole while losses were occurring
• Not identifying the kick more rapidly

Just one of those errors in and of itself is bad. All five together? Ouch. Double ouch. Triple ouch.

A mud volcano may sound like a funny thing, but I don't think anyone in the area is laughing. Take a look at the extent of the mud flow, courtesy of NASA. The area basically sits on a giant, extensional basin full of highly pressurized carbonate mud and petroleum. Lots of petroleum. Drilling there requires getting to the oil and gas while avoiding mud volcano systems, which apparently failed, in this case. Badly. It's sort of like poking a hole in a water bed that someone's sitting on; no wonder Lusi has been erupting for six years already and is expected to continue to do so for another thirty. There's a lot of mud, under a lot of pressure, and a nice little path to the surface.

Fracturing Follow-up

After a small discussion in my previous post about hydraulic fracturing, I decided to look in to the subject a little more deeply, since the commenter focused strongly on concerns related to horizontally drilled wells. Horizontal wells weren't really mentioned in the articles I linked to, but horizontal drilling is becoming the common method for extracting gas from tight shales and will likely be used in the development of the Marcellus Shale. As such, it's more than fair to look at the practice and see if there are issues unique to it, or problems that occur more commonly in horizontal rather than vertical wells.

One thing I've noticed so far in researching is that papers that could answer that concern are few and far between. Looking at both GeoRef and GeoScience World, many reference hits are to expanded abstracts from meetings, and most of those are related to the effects of horizontal drilling on reservoir development rather than environmental impact. The EPA is also unhelpful on the topic; as the practice of hydraulic fracturing has been excluded from the Safe Drinking Water Act, the EPA isn't in a position to look in to the safety from an environmental standpoint. The one study they have done relates to coal bed methane. In their coal bed methane study, the EPA concludes:

Although potentially hazardous chemicals may be introduced into USDWs when fracturing fluids are injected into coal seams that lie within USDWs, the risk posed to USDWs by introduction of these chemicals is reduced significantly by groundwater production and injected fluid recovery, combined with the mitigating effects of dilution and dispersion, adsorption, and potentially biodegradation. Additionally, EPA has reached an agreement with the major service companies to voluntarily eliminate diesel fuel from hydraulic fracturing fluids that are injected directly into USDWs for coalbed methane production.

However, that said, the coal bed methane situation is arguably not quite the same, since most coal beds used in that study were fairly shallow, and many in direct "communication" with adjacent formations or aquifers. As a side geological note, coal layers can often act as barriers to fluid (such as hydrocarbons) flow from lower formations to upper formations, since they're only really permeable via fractures. Also, the conclusions have been called in to question in 2004 by an EPA employee named Weston Wilson:

While EPA's report concludes this practice poses little or no threat to underground sources of drinking water, based on the available science and literature, EPA's conclusions are unsupportable. EPA has conducted limited research reaching the unsupported conclusion that this industry practice needs no further study at this time. EPA decisions were supported by a Peer Review Panel; however five of the seven members of this panel appear to have conflicts-of-interest and may benefit from EPA's decision not to conduct further investigation or impose regulatory conditions.

An apparent conflict of interest is certainly something to look in to. I found one site that said Mr. Wilson's concerns were considered valid enough to prompt further investigation, though I have no idea if that investigation occurred or what the conclusion turned out to be. So I think for now, we'll skip the coal bed methane study.

The commenter made two points that I looked in to, which I've paraphrased here:

1) That the fractures made by hydraulic fracturing can extend further than intended, and in to different zones than are desired, possibly putting the aquifer at risk.

I tend to think that subsurface, technically anything is possible; geophysics is a difficult field (certainly not one I've mastered) since the conditions are uncontrolled and it's nigh impossible to know what the underground stress field is like precisely or what zones of weakness/minor faults may also exist. So is it possibly that a fracture created in a deep zone could "go rogue" (oh, I feel dirty just typing those words!) and go 4,000 feet up in to an aquifer? Possible, yes, but I would venture to say highly unlikely and would probably require an existing network of fractures/faults to do. The EPA coal bed methane study does actually say one thing of use about this matter, which holds true even if we're not talking coal bed methane:

A hydraulic fracture will propagate perpendicularly to the minimum principal stress. In some shallow formations, the least principal stress is the overburden stress; thus, the hydraulic fracture will be horizontal. In deeper reservoirs, the least principal stress will likely be horizontal; thus, the hydraulic fracture will be vertical.

Basically, the generic stress you'd expect in a deep formation would cause the fractures to tend to propagate upward. However, the general stress field will change as you approach the surface, and there are going to be other stress factors that may redirect fractures along the way. Intervening formations with different properties and different zones of weakness also have an important effect. A basin is in no way homogeneous vertically - and often formations will change their properties over horizontal distance as well. The New York Department of Environmental Conservation SGEIS report is a little more specific:

ICF – citing PTTC, 2006 – concludes that: “In the Appalachian Basin, the stress state would be expected to lead to predominantly vertical fractures below about 2500 feet, with a tendency towards horizontal fractures at shallower depths.”

Depending on the depth of the aquifer, this conclusion makes the propagation of a vertical fracture in to it seem fairly unlikely.

At this point, the best that can be done is computer modeling, which has become increasingly sophisticated - though it can always be argued of course that we lack perfect knowledge of sub surface conditions. However, the fact of the matter is that it's in the best interest of the people fracturing the formation to prevent such wild fracture propagation from happening. Going outside the intended zone tends to mean getting a lot of unintended fluid - normally salt water - which has to be separated and disposed of, not something that is cheap or convenient to do.

The New York Department of Environmental Conservation has a report that's an overview of the historical and current practice of horizontal drilling and hydraulic fracturing here. I think the authors of the report make a valid point by stating:

Not only is fracture growth outside of the target formation discouraged relative to the potential of reduced production by production of fluids from non-productive zones, creating fracture size outside of the productive interval is more expensive and less cost beneficial to the well’s economics.

The DEC SGEIS also quotes ICF again in noting:

• The developable shale formations are vertically separated from potential freshwater aquifers by at least 1,000 feet of sandstones and shales of
moderate to low permeability.
• The amount of time that fluids are pumped under pressure into the target formation is orders of magnitude less than the time that would be required for fluids to travel through 1,000 feet of low-permeability rock.
• The volume of fluid used to fracture a well could only fill a small percentage of the void space between the shale and the aquifer.
• Any flow of fracturing fluid toward an aquifer through open fractures or an unplugged wellbore would be reversed during flowback, with any residual fluid further flushed by flow from the aquifer to the production zone as pressures decline in the reservoir during production.

These factors point to groundwater contamination without wild fractures going a thousand or more feet farther than intended being highly unlikely as well.

At this point, the question of the threat that the fracturing practice has on the ground water becomes a cost/benefit analysis. It's in the best economic interest of the company developing the well to model their fractures properly to ensure that they do not move out of the intended zone. But it's also fair to argue that modeling is imperfect and that the most bizarre accidents can happen. Is that amount of risk worth the economic benefit?

2) Horizontal wells carry a greater risk of inducing harmful seismic activity which can cause an array of problems.

I'm actually already familiar with the concept of just plain old vertical wells inducing seismic activity; I doubt horizontal wells would be at all different. It's certainly not a new concept. Most of the reading I've done on this subject relates to disposal wells; in particular there was a case in Colorado where a deep disposal well was lubricating nearby faults and causing them to reactivate. The seismic activity in these cases is generally pretty low level (0 to 3 on the Richter Scale) and mostly an argument for being careful where one puts one's disposal wells - and for not overpressurizing them.

Subsidence is another matter that goes with the extraction of any fluid from a reservoir. With the reservoir losing pressure and volume with the removal of fluid, it can compact, which destroys reservoir permeability and causes subsidence. Subsidence also occurs and is a significant threat when aquifers are overused for drinking water. Basically, any time fluid is taken out of the ground and not replaced, there will be subsidence. From the US Department of Energy:

The most famous early instance was in Wilmington, California, where the oil production triggered a series of damaging earthquakes. In this instance the cause of the seismicity was traced to subsidence due to rapid extraction of oil without replacement of fluids. Once this was realized the oil extraction was balanced with water injection to mitigate the seismicity. Ever since then the oil and gas industry has adopted these practices to mitigate seismicity , but also mitigate damage to the oil wells in the producing field (wells would be sheared off in the subsurface as subsidence occurred).

The practice of reinjecting fluid isn't exactly perfect - if nothing else there are cases where the replacement fluid can't be returned to the right location and overpressurization can occur.

With the reading, I've done, I tend to agree with the DoE assessment:

Overall the impact of induced seismicity on the implementation of various different energy recovery and or disposal activities will depend on the risk associated with the activity and the cost-benefit ratio. All experience to date has shown that the risk, while not zero, has been either minimal or can be handled in a cost effective manner.

So once again, this comes to a question of cost/benefit analysis. Are the possible seismic dangers present worth the economic benefit? Are the means by which the concern about subsidence good enough at mitigating the problem? Since we live in a less than perfect world, it becomes a personal choice if the mitigation of the risk makes the development of the resource worth it. Though I think it is worth noting that in the DEC review of the pertinent geology that comes from their SGEIS, they state that in at least New York, the Marcellus and Utica shales underlie the areas of lowest seismic risk.

The DoE also makes a point of separating the induced seismicity associated with fluid injection and extraction from hydraulic fracturing:

Hydrofracturing is distinct from many types of induced seismicity because hydrofracturing is by definition only created when the forces applied create a type of fracture called a “tensile” fracture, creating a “driven” fracture... To our knowledge hydrofracturing to intentionally create permeability rarely creates unwanted induced seismicity large enough to be detected on the surface with very sensitive sensors, let alone be a hazard or annoyance.

I think the crux of this issue becomes the phrase "to our knowledge." With what data and studies are available, it seems this is not something to be overly concerned about. However, I think a good argument can also be made in regards to needing more knowledge and more research. At this time, since the practice of hydraulic fracturing is in many ways proprietary and also exempt from government oversight, that makes the study of it in regards to environmental impacts difficult. I think that an NPR story on this topic sums it up nicely:

Critics of hydraulic fracturing suspect that the chemicals used in the process have somehow leaked into the groundwater supply. It has been difficult, however, to demonstrate a direct connection between these apparent instances of water pollution and the hydraulic fracturing procedures that have taken place nearby...It is also true, however, that state regulators have not been able to disprove a connection between hydraulic fracturing and water contamination.

At this time, it's not something that could be directly proven or disproven. Off the top of my head, I think there are experiments that could be conducted that could tell us if:
a) Is there groundwater pollution associated with fracturing fluid?
b) Is this contamination associated with surface pollution or with the underground process?

For example, if you could add an inert "tracer" compound to fracturing fluid, you could then check if contaminated water had that tracer in it. As far as discerning between surface contamination and subsurface contamination, that might be more difficult. Though I imagine geologists who know far more about hydrology than I do may be able to determine the source just by looking at how quickly the contamination showed up. If you have contamination showing up in a reservoir two days after a nearby well has been fractured (and our mythical tracer compound shows it was from that well) then the next question is if a subsurface fracture could have possibly delivered fluid that quickly; if not, the more likely culprit is surface run off from an accident or inadequately observed safety practices.

Either way, this is all very pie in the sky. I'll be interested to see more on this subject as more data is collected.

As a final note, the Department of Energy Induced seismicity primer is honestly a fascinating read in and of itself and I'd highly recommend it. I also recommend the New York Department of Environmental Conservation report that I linked to above as well, since it's also a very good historical overview. The DEC also has a review of the pertinent geology that comes from their SGEIS that's definitely worth a read. There is also a good description of the drilling process and equipment used from the SGEIS, which also includes a look at slickwater fracturing as used in the development of the Marcellus Shale.

Edit: An anonymous comment was left rather incongruously my post about Heene being sentenced. The commenter left a link for another bit of good reading on this topic, however: Impact Assessment of Natural Gas Production in the New York City Water Supply Watershed. The report covers quite a bit about the underlying fractures/faulting that was not in the other reports I read.

Hydraulic fracturing

I hadn't actually heard about the proposed regulation to subject hydraulic fracturing to the Safe Drinking Water Act. I suppose I've been too inundated with the entire horrific healthcare mess to hear much of anything else. I don't have any problems with Congresswoman DeGette's proposal - and I'm not just saying that because I voted for her.

Hydraulic fracturing is something that's actually been in use for quite some time in the United States - at this point, a little bit over fifty years. Obviously, length of use doesn't necessarily say anything about a practice's safety; there are plenty of industrial practices that have been in use for far longer that do not-nice things to the environment and to people. I mostly point this out because by now, the practice is ubiquitous in the industry. When I started working for my company* as a temp four years ago, some of the first reports I ever read detailed how formations were being fractured.

The basic one sentence explanation in the article is fair enough, but I'd like to go in to just a little more detail about the what and why. Most fluids that we're interested in getting out of rocks (water, oil, natural gas) are locked in sedimentary rocks**. We're used to thinking of rocks as very solid things; the fact of it is, many of them are surprisingly un-solid. There are two very significant properties to these sedimentary rocks that determines how hard it's going to be to extract the fluid.

The first is porosity - just how much "air space" there is in a rock. (Picture here) These spaces in the rock are basically the gaps between the grains that have been cemented together to form the rock. The higher the porosity of the rock, the more of your fluid of interest it can contain.

The second important quality is permeability - just how interconnected are the spaces in the rock? For example, a rock could potentially be quite porous, but if each of the spaces in it are completely isolated, it would be impossible for fluid to flow through the rock.

Permeability is a nice quality for a reservoir rock to have. If you want to get fluid out of that rock and it's nice and permeable, often all you really have to do is drill down into the rock and then let the pressure differential do the work for you. The fluid in the rock will be under a lot more pressure than what's in the well, so the liquid will just move on its own. But if a rock's not very permeable, that fluid flow doesn't happen easily because there just aren't many paths for the fluid to travel. Rocks like that are referred to as "tight."

Enter hydraulic fracturing. At its most basic, you just pump a lot of water and sand down in to a formation, under high pressure. The water finds zones of weakness in the formation and fractures them further; the sand keeps the fractures open. The end result is the creation of a lot more paths through which fluid can move through the formation and in to your well. However, there's also the addition of a lot of chemicals to the fracturing process, many of which are included to help keep the sand from clumping up and clogging the fractures that you've just made.

For the most part, I don't see a lot of problems with the basic practice of hydraulic fracturing. (Not on the table for discussion at the moment: the basic practice of using fossil fuels.) It aides in production - sometimes making it possible to produce from formations that would otherwise not produce at all - and ups the amount of fluid recovery. Most of the time, oil and gas producing formations are far deeper than the water table and properly done fracturing shouldn't intrude anywhere near it. That said, a lot of the time you're drilling through an aquifer to get where you need to go, or more importantly, fluid spills can occur at the surface or nasty things may find a way to escape waste pits. Even if you've got the most environmentally conscious and careful drilling company in the world, accidents can happen and should not be ignored. It doesn't take too many mistakes to harm an aquifer and potentially hurt all of the people who rely on it for their water.

In my rather inexpert opinion (and from the news articles I've read thus far) the main problem with fracturing doesn't seem to be the process in the ground, but rather spills and waste collection at the surface. Thus, I don't think banning hydraulic fracturing would necessarily solve the basic problem, which at this point appears to be surface safety, and would quite possibly have an adverse effect on the natural gas market***. If there's real, substantiated concern (which there seems to be) over contamination of ground water, then the Safe Drinking Water Act no doubt has something to say about it. Though I am also forced to wonder if adding another layer of regulation will do much good if current safe practice requirements are not being properly enforced.

Side note: There's quite the collection of links for groundwater contamination news stories at the site NoFracking.com. I used the site as a link mine to see what contamination complaints/news was out there rather than as an informational source.



* I am an intern at an oil company. My opinions are not in any way the opinions of my company.

** Some times you'll get water out of an igneous/metamorphic rock because it's seeped in to fractures from the surface, or from an underlaying sedimentary reservoir. We won't worry about that here.

*** Your mileage on this may vary, depending on how worried you are about the price of natural gas versus the possibility of finding some extremely scary chemicals in your drinking water.