Carbon Capture and Storage Could Contaminate Drinking Water

Carbon capture and storage (CCS) is a technical “solution” to the CO2 emissions produced by fossil fuelled power plants and much favoured by companies and governments who wish to continue “business as usual” rather than taking action which would avoid producing CO2.

There are a number of problems with CCS – not least is that this “solution” does not yet exist anywhere in the world at the necessary scale – but, given the recent news about E.ON  possibly bidding for government CCS funds for their Isle of Grain power plant, I thought it worthwhile highlighting a recent study by scientists from Duke University in America.

Isle of Grain CHP

E.ON's gas plant at the Isle of Grain. Source: Utility Week.

CO2 leakage from storage could pose a risk to overlying fresh groundwater, therefore, the scientists performed laboratory incubations of CO2 infiltration under oxidizing conditions for more than 300 days on samples from four freshwater aquifers with a view to:

  1. understanding how CO2 leakage affects freshwater quality;
  2. developing selection criteria for deep sequestration sites based on inorganic metal contamination caused by CO2 leaks to shallow aquifers; and
  3. identifying geochemical signatures for early detection criteria.

CO2 caused concentrations of the alkali and alkaline earths and manganese, cobalt, nickel and iron to increase by more than two orders of magnitude. In addition, potentially dangerous uranium and barium increased throughout the experiment in some samples. The scientists concluded that manganese, iron, calcium and pH could be used as geochemical markers of a CO2 leak as their concentrations increase within two weeks of exposure to CO2.

Reporting on this study, the Ecologist states that a spokesperson for the Department for Energy and Climate Change said any potential storage of CO2 underground would be monitored closely by the Environment Agency to avoid possible contamination issues. Note that there is no indication how the CO2 storage would be monitored and how such monitoring would avoid contamination issues.

Given part of the reason for the study by Duke University was to identify geochemical signatures for early detection (not the avoidance) of contamination and the scientists found markers indicating contamination up to two weeks earlier, the Department for Energy and Climate Change’s comment does not seem reassuring.

David M. Davison

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s