“CLEAN” COAL -> TOXIC WATER

Study Charts How Underground CO2 Can Leach Metals into Water; Study is the first to observe, for at least a year, the effects of a CO2 leak on groundwater
Catherine M. Cooney, December 7, 2010 (Solve Climate News)

"…[N]ew research indicates that if CO2 stored deep underground were to leak in even small amounts, it could cause metals to be released in shallow groundwater aquifers at concentrations that would pose a health risk.

"…[In Potential Impacts of Leakage from Deep CO2 Geosequestration…]…samples of sand and rock taken from four freshwater aquifers located around the country that overlie potential carbon capture and sequestration (CCS) sites…[showed] that tiny amounts of CO2 drove up levels of metals including manganese, cobalt, nickel, and iron in the water tenfold or more in some places. Some of these metals moved into the water quickly, within one week or two. They also observed potentially dangerous uranium and barium steadily moving into the water over the entire year-long experiment…"

Vulnerable groundwater (from the study - click to enlarge)

"The technology for capturing and storing CO2 emissions from coal plants and industrial facilities is not yet commercially available. Still, the Obama Administration and other governments consider capturing carbon dioxide and sequestering it underground a vital technology that will allow the world to continue using coal as fuel while reducing the impacts of climate change. This new study sheds further light on how fresh water contamination from the technology could potentially occur…

"When the CO2 buried deep underground escapes into groundwater, it forms carbonic acid, a chemical reaction very similar to the process that occurs when the oceans absorb CO2. But the problems created by the carbonic acid in groundwater are quite different from the reactions that occur in the ocean…[A]tmospheric CO2 is causing ocean acidification that is harming corals, shellfish, lobsters, and other marine animals at the bottom of the sea. The increased acidity caused by CO2 dissolved in water underground can cause metals to leach out of surrounding sand and rock."

Areas of study (click to enlarge)

"Borrowed from agencies such as the US Geological Survey, the sediment used in the study was from 17 locations within four project sites…[O]bservations of the leaking CO2 [will help] develop [sequestration site] selection criteria, based on the metal contamination seen in the water, to help owners and operators choose CCS sites that are less likely to contaminate nearby freshwater aquifers…[The research] also identified four geochemical markers to help monitor sites and discover when CO2 has leaked and caused metals to move into the groundwater…

"…[T]he research is unique because of its length: it is the first to observe, for at least a year, the effects of a CO2 leak on groundwater…Scientists have already conducted short-term experiments of two-weeks to one month and found that CO2 in very small amounts can escape along rock faults and old petroleum wells into near-by groundwater and release harmful metals such as arsenic and uranium into the water…Other researchers are trying to determine how a very large leak might affect the subsurface environment, while the Department of Energy (DOE) and private investors are beginning studies of potential groundwater contamination in the field…"