I looked up the geography and geology of Pavillion: it lies in the western half of Wyoming, a region dominated by the Rocky Mountains. There will be sediments in the basins, but the fundamental underlying geology is contorted and fractured mountain zone rock.
As a result, I am entirely unsurprised that both natural gas and fracking chemicals are finding their ways into the groundwater. I am surprised that how this can be, is a still a matter of legal debate.
I am no geologist, but even I can understand what is happening, and how, and I published it as a guest column in the Waco Tribune Herald last May. Here is the original submitted text for that column, with some emphasis added now:
Coming Even Cleaner on Fracking” (submitted 5-26-11/published 5-28-11)
The “Trib’s” editors recently ran a very nice editorial on the controversy surround the process of “fracking” (short for “hydraulic fracturing”) for natural gas in shale. This article neatly laid out the two sides of the public debate, which is centering mainly on whether or not there are undesirable side effects.
I find it very interesting that the studies are "still inconclusive", seeing as how the field data is very indicative of what actually happens. It's not a simple either-or situation, it’s geology-dependent, and this is completely left out of the current public debates.
Here in Texas and nearby states, the rock layers are old seabed sediments, more or less level, and are relatively intact. Few paths exist across these layers for oil and gas to migrate upward. That is why fracking has few side effects in this part of the country. The most notable exception has been very minor earthquake tremors induced from the disposal of used fracking fluids by deep well injection.
In Pennsylvania and the other states in the Appalachian mountain zone, there have been widespread complaints about natural gas getting into groundwater, leading to fire and explosion incidents when turning on the water tap. These are real incidents, and are easy to understand if one simply looks at the geology below the surface.
In a mountain zone, the rock layers are highly contorted, fractured, and thoroughly broken-up. There are many paths for oil, and especially the far-more-mobile gas, to migrate to the surface. It is entirely unsurprising, and in fact quite predictable, that this very mobile gas, once released from a deep shale, should migrate upward and contaminate near-surface water supplies. It does so by dissolving into the water under earth pressures, similar to a carbonated beverage.
The solution to the exploding kitchen faucet problem is simple: fracking for gas is OK in continuous-layered sea bottom sediment zones, but not OK in highly-fractured mountainous zones. So, we don't frack there, period. Those gas deposits await a still-undiscovered recovery technology with fewer side effects, more suited to that kind of geology.
This does mean that the agencies regulating gas leases actually do have to regulate, and sometimes to deny permits, unaccustomed as they apparently are to such activities.
The processes of fracking and fracking-fluid disposal were specifically exempted from EPA regulation under the Clean Water Act. This happened in that secretive energy company meeting at the White House during the last administration. It is known as the Halliburton exemption.
However, the injection of diesel fuel into the earth is actually still regulated. While fracking fluid is mostly water plus a little sand or glass beads, the most common liquid trace additive in all these "secret" recipes is diesel fuel. If those recipes were widely revealed, the use and disposal of these fluids would come under direct EPA regulation again, meaning only that they take a little better care doing what they already do.
In that event, fracking for gas would still be quite profitable, just not quite as much as it is without any regulation at all. But fewer folks suffer the side effects, and that’s a good thing.
Update 1-3-15:
The recent explosion of US “fracking” technology (hydraulic
fracturing plus horizontal-turn drilling) has modified the picture of oil
prices versus recessions.
Unexpectedly, the US has become a
leading producer of crude oils for the world market. Plus,
there has been an associated massive production increase and price drop
in natural gas.
OPEC has chosen to take the income “hit” and not cut back
their production in response. Their
reasoning is twofold: (1) fear of loss
of market share, and (2) hope that low
oil prices will curtail US “fracking” recoveries. We will see how that plays-out.
Oil prices are now such (at around $55/barrel) that US
regular gasoline prices are nearing $2.00/gal for the first time in a very long
time. This is very close to the price
one would expect for a truly competitive commodity, based on 1958 gasoline prices in the US, and the inflation factor since then.
It is no coincidence that the exceedingly-weak US “Great Recession”
recovery has suddenly picked up steam.
The timing of the acceleration in our economic recovery versus the
precipitous drop in oil prices is quite damning. There can be no doubt that
higher-than-competitive-commodity oil prices damage economies. Oil prices are a superposition of the competitive
commodity price, overlain by an erratic
increase from speculation, and further overlain
quite often by punitive price levels when OPEC is politically unhappy with the
west. That’s been the history.
This economic improvement we are experiencing will persist
as long as oil, gas, and fuel prices remain low. (Government policies have almost nothing to
do with this, from either party.) How long that improvement continues depends
in part upon US “fracking” and in part upon OPEC. Continued US “fracking” in the short term may
depend upon adequate prices. In the long
term, we need some solutions to some
rather intractable problems to continue our big-time “fracking” activities.
The long-term problems with “fracking” have to do with (1)
contamination of groundwater with combustible natural gas, (2) induced earthquake activity, (3) lack of suitable freshwater supply to
support the demand for “fracking”, and
(4) safety problems with the transport of the volatile crude that “fracking”
inherently produces.
Groundwater
Contamination
Groundwater contamination is geology-dependent. In Texas,
the rock layers lie relatively flat,
and are relatively undistorted and unfractured. This is because the rocks are largely old sea
bottom that was never subjected to mountain-building. We Texans haven’t seen any significant
contamination of ground water by methane freed from shale. The exceptions trace to improperly-built
wells whose casings leak.
This isn’t true in the shales being tapped in the
Appalachians, or in the shales being
tapped in the eastern Rockies. There the
freed gas has multiple paths to reach the surface besides the well, no matter how well-built it might have
been. Those paths are the vast
multitudes of fractures in the highly-contorted rocks that subject to mountain-building
in eons past. That mountain-building may
have ceased long ago, but those cracks
last forever.
This is why there are persistent reports of kitchen water
taps bursting into flames or exploding,
from those very same regions of the country. It’s very unwise to “frack” for gas in that
kind of geology.
Induced Earthquake
Activity
This does not seem to trace to the original “fracking”
activity. Instead it traces rather
reliably to massive injections of “fracking” wastewater down disposal
wells. Wherever the injection quantities
are large in a given well, the frequent
earthquakes cluster in that same region.
Most are pretty weak, under
Richter magnitude 3, some have
approached magnitude 4.
There is nothing in our experience to suggest that magnitude
4 is the maximum we will see. No
one can rule out large quakes. The risk is with us as long as there are
massive amounts of “fracking” wastewater to dispose of, in these wells. As long as we never re-use “frack”
water, we will have this massive
disposal problem, and it will induce
earthquakes.
Lack of Freshwater
Supply to Support “Fracking”
It takes immense amounts of fresh water to “frack” a single
well. None of this is ever re-used, nor it is technologically-possible to
decontaminate water used in that way. The
additives vary from company to company,
but all use either sand or glass beads,
and usually a little diesel fuel.
Used “frack” water comes back at near 10 times the salinity of sea
water, and is contaminated by heavy
metals, and by radioactive minerals, in addition to the additives. Only the sand or glass beads get left
behind: they hold the newly-fractured
cracks in the rocks open, so that
natural gas and volatile crudes can percolate out.
The problem is lack of enough freshwater supplies. In most areas of interest, there is not enough fresh water available to
support both people and “fracking”, especially
with the drought in recent years. This assessment
completely excludes the demand increases due to population growth. That’s even worse.
This problem will persist as long as fresh water is used for
“fracking”, and will be much, much worse as long as “frack” water is not
reused. The solution is to start with
sea water, not fresh water, and then to re-use it. This will require some R&D to develop a
new additive package that works in salty water to carry sand or glass
beads, even in brines 10 times more
salty than sea water.
Nobody wants to pay for that R&D.
Transport Safety with
Volatile “Frack” Crudes
What “fracking” frees best from shales is natural gas, which is inherently very mobile. Some shales (by no means all of them) contain
condensed-phase hydrocarbons volatile enough to percolate out after hydraulic
fracturing, albeit more slowly than
natural gas. Typically, these resemble a light, runny winter diesel fuel, or even a kerosene, in physical properties. More commonly, shale contains very immobile condensed
hydrocarbons resembling tar. These cannot
be recovered by “fracking” at all.
The shales in south Texas,
and some of the shales and adjacent dolomites in the Wyoming region
actually do yield light, volatile
crudes. The problem is what to transport
them in. There are not enough
pipelines to do that job. Pipelines are safer
than rail transport, all the spills and
fires notwithstanding.
The problem is that we are transporting these
relatively-volatile materials in rail tank cars intended for normal (heavy)
crude oils, specifically DOT 111 tank cars. Normal crudes are relatively-nonvolatile and
rather hard to ignite in accidents. DOT
111 cars puncture or leak frequently in derail accidents, but this isn’t that serious a problem as long
as the contents are non-volatile. These
shale-“frack” light crude materials resemble nothing so much as No. 1 winter
diesel, which is illegal to ship in DOT
111 cars, precisely since it is too
volatile.
The problem is that no one wants to pay for expanding the
fleet of tougher-rated tank cars. So, many outfits routinely mis-classify “frack” light
crudes as non-volatile crudes, in order
to “legally” use the abundant but inadequate DOT-111 cars. We’ve already seen the result of this kind of
bottom line-only thinking, in a series
of rather serious rail fire-and-explosion disasters, the most deadly (so far) in Lac
Megantic, Quebec.
Volatile shale-“fracked” crudes simply should not be shipped
in vulnerable DOT 111 cars, period. It is demonstrably too dangerous.
Conclusions
“Fracking” shales for natural gas and light crudes has had a
very beneficial effect on the US economy and its export-import picture. We should continue this activity as a
reliable bridge to things in the near future that are even better.
But, we must address
the four problem areas I just outlined.
And I also just told you what the solutions are. The problem is, as always,
who pays. What is the value of a
human life? What is the value of a
livable environment? It’s not an either-or
decision, it’s striking the appropriate balance!
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