Leaking underground CO2 storage could contaminate drinking water

Nov 11, 2010

Leaks from carbon dioxide injected deep underground to help fight climate change could bubble up into drinking water aquifers near the surface, driving up levels of contaminants in the water tenfold or more in some places, according to a study by Duke University scientists.

Based on a year-long analysis of core samples from four aquifers, "We found the potential for contamination is real, but there are ways to avoid or reduce the risk," says Robert B. Jackson, Nicholas Professor of Global Environmental Change and professor of biology at Duke.

"Geologic criteria that we identified in the study can help identify locations around the country that should be monitored or avoided," he says. "By no means would all sites be susceptible to problems of water quality."

The study appears in the online edition of the journal Environmental Science & Technology.

Storing carbon dioxide deep below Earth's surface, a process known as geosequestration, is part of a suite of new carbon capture and storage (CCS) technologies being developed by governments and industries worldwide to reduce the amount of greenhouse gas emissions entering Earth's atmosphere. The still-evolving technologies are designed to capture and compress CO2, emissions at their source – typically power plants and other industrial facilities – and transport the CO2 to locations where it can be injected far below the Earth's surface for long-term storage. The U.S. Department of Energy, working with industry and academia, has begun the planning for at least seven regional CCS projects.

"The fear of drinking water contamination from CO2 leaks is one of several sticking points about CCS and has contributed to local opposition to it," says Jackson, who directs Duke's Center on Global Change. "We examined the idea that if CO2 leaked out slowly from deep formations, where might it negatively impact freshwater aquifers near the surface, and why."

Jackson and his postdoctoral fellow Mark G. Little collected core samples from four freshwater aquifers around the nation that overlie potential CCS sites and incubated the samples in their lab at Duke for a year, with CO2 bubbling through them.

After a year's exposure to the CO2, analysis of the samples showed that "there are a number of potential sites where CO2 leaks drive up tenfold or more, in some cases to levels above the maximum contaminant loads set by the EPA for potable water," Jackson says. Three key factors – solid-phase metal mobility, carbonate buffering capacity and electron exchanges in the overlying freshwater aquifer – were found to influence the risk of drinking water contamination from underground carbon leaks.

The study also identified four markers that scientists can use to test for early warnings of potential leaks. "Along with changes in carbonate concentration and acidity of the water, concentrations of manganese, iron and calcium could all be used as geochemical markers of a leak, as their concentration increase within two weeks of exposure to CO2," Jackson says.

Explore further: Feds protect 20 species of coral as threatened

More information: http://pubs.acs.org/doi/abs/10.1021/es102235w

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User comments : 15

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Skepticus_Rex
2.7 / 5 (7) Nov 11, 2010
Leave it in the atmosphere, then, or convert it to something else.

The earth will take care of it over time. The earth removed nearly half of our emissions over a period of 15 years.
Royale
3.9 / 5 (7) Nov 11, 2010
A: CO2 has a very strong bond, the energy required to 'convert it' would be astronomical.

B: Provide a source that earth removed half of our emissions over 15 years. If by remove you mean 'moved elsewhere on earth' then perhaps, but that's still unbelievable without a reliable source. And I'm just talking CO2, if you mean emissions in general; how exactly does the earth remove CO from cars, or mercury from electronics? The list can go on.

The pacific ocean has removed miles of plastic and debris over 15 years. That doesn't mean it's gone.
marjon
1.6 / 5 (7) Nov 11, 2010
How does CO2 contaminate water?
They sell such water in stores and call it seltzer.
Graeme
5 / 5 (1) Nov 11, 2010
Well CO2 in water makes it more acidic, and it can dissolve more metals from the rock. But can the liquid CO2 dissolved material underground itself?
Skepticus_Rex
2.6 / 5 (5) Nov 11, 2010
marjon, the paper explains how. The summary above explains that it does. But, that is just a summary. It is different from the process that creates seltzer.

Royale,

A. Magnesium can burn in pure CO2, and can even burn under water, because it rips oxygen from CO2. Ever hear of a Class D magnesium fire? You don't want to be near one much less a full scale one.

B. All carbon sinks in nature removed nearly 50% of anthropogenic CO2 from the atmosphere. Yes, it of course went somewhere else, but it left the atmosphere.

http://www.gcrio....-7-1.pdf

See also page 4 of the following link for another interesting and related statistic:
http://unesdoc.un...137e.pdf

You will also want to read the following:
http://www.agu.or...13.shtml

Your 'trash in the Pacific' analogy does not really fit the CO2 sinks situation, but ok...
stealthc
1 / 5 (5) Nov 11, 2010
more co2=more plants=more converting co2 to oxygen. sunlight is enough to break that tough carbon bond, and I suspect splitting water can be done in a similar fashion. Nanotech has already solved most of this problem. Stop dicking around and bet your money on what is going to actually work, this underground storage sounds like lunacy when you consider the alternatives.

Leave it to the retarded powers that be to NOT make a good bet, similar to what they have done with your retirement income.
marjon
2.3 / 5 (6) Nov 11, 2010
How will the collapse of the carbon trading exchange?
"Launched as a "voluntary" method of trading "carbon credits," CCX rested on the hope that cap-and-tax legislation would make such trading mandatory — and profitable."
"The biggest losers are CCX's two biggest investors, Al Gore's Generation Investment Management and Goldman Sachs, that champion of sound money management that serves as the farm team for administration staffing."
http://www.invest...&p=2
marjon
2.6 / 5 (5) Nov 11, 2010
Correction for my last:
How will the collapse of the the carbon trading exchange affect CO2 storage?
Skepticus_Rex
3 / 5 (4) Nov 12, 2010
I mentioned converting CO2 to something else earlier. I knew that there were some stories around here about new breakthroughs that potentially could allow that to happen. They are the following links (I am sure there are more but don't feel like searching for them at the moment).

http://www.physor...915.html

http://www.physor...624.html
Noumenon
4.8 / 5 (49) Nov 12, 2010
Any and all technologies that may continue to allow carbon based energy sources to be used even though potentially cleaner, will and is being suspiciously attacked.
Skeptic_Heretic
3.7 / 5 (3) Nov 12, 2010
Any and all technologies that may continue to allow carbon based energy sources to be used even though potentially cleaner, will and is being suspiciously attacked.
Yes, and I disagree with this radicalism we've seen in the discussion. If you can build me an ICE that emits nothing and is highly fuel efficient, I'd buy it.

There are a few carbon based fuels I'd like to be rid of, but that's more for geopolitical and particulate pollution reasons.
Skepticus_Rex
2.3 / 5 (3) Nov 14, 2010
Same here--on both counts.
GSwift7
1 / 5 (3) Nov 15, 2010
This is ironic really. The environmental movement is now trying to prevent cleaning the air for fear of polluting the ground.

I wonder who paid for this study, and what the political angle is supposed to be. This is obviously intended to influence policy by creating a potential roadblock for this method of CO2 sequestration. Could it be proponents of some other competing method at work here? The impacts of pumping CO2 into the ground are surely already being investigated on a site by site basis whereever this is being considered. My BS article radar is showing a blip on my screen right now.

Four samples, one year in a lab? No computer models? Aren't there any places in nature where gasses are venting up through the ground that could be used to observe the process on a large scale in the real world?
Skepticus_Rex
1 / 5 (2) Nov 15, 2010
Write the author and find out, and definitely read the paper itself.

What computer models would match physical observation of chemical reactions and reagent action?

There are many things we could do that we shouldn't do because they end up being worse than the problem in the long run, and tend to affect the environment in unforeseen ways. It is sort of like the way in which iron seeding was considered in order to cause planktons to sequester CO2. Toxic blooms would result and harm the environment far worse than CO2 ever could, as well as poison people nearby the blooms as well as end-users of oceanically-based products.

I, for one, am glad that somebody did the science first before actually putting such kinds of CO2 sequestration into universal practice, only to find out the hard way that they shouldn't have done what they did. If only they had had the foresight to do the same for current solar technologies, several of which will do far more harm to the environment than CO2.
freethinking
2.3 / 5 (3) Nov 15, 2010
If the world survives the crazy environmentalist trying to get rid of C02 it will be amazing.

How much money has been wasted in researching how to eliminate CO2. If Al Gore wants to save lives, we need to research fresh water sources, green revolution (ie more food production), elimination of governmental corruption.