Carbon dioxide leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column into the marine environment is a great threat for marine life and human health. The impact of the effects depend on the rate of leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column, extent and geometry of leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column, nature and composition of marine sediments, sensitivity of species to increased contents of CO2Carbon dioxide and the presence of other contaminants in the CO2 streamA flow of substances resulting from CO2 capture processes, or which consists of a sufficient fraction of CO2 and sufficiently low concentrations of other substances to meet specifications of streams permitted for long term geological storage.
One of the effects of an eventual leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column into the marine environment would be acidification of the oceans caused by a decrease in pH. A study made at a natural underwater gas vent near Panarea Island (Italy) in 2008 revealed that in the gas vent area the pH has decreased to 7.68 at 10 m depth and 7.78 at 5 m depth (see Fig. 3-4.) from the normal values of 8-8.2 (Espa et al., 2010).
Seawater acidification together with an increase of CO2Carbon dioxide content in marine sediments may produce adverse effects to marine life such as: dissolution of calcareous shells, decrease in ability to build calcareous skeletal structures including reefs, metabolic rate reductionThe gain of one or more electrons by an atom, molecule, or ion, decrease in reproduction rates and increase of mortality rates, both among planktonic and benthicRelating to the bottom of a sea or lake or to the organisms that live there organisms (Kirk, 2010). The decrease of pH in marine sediments can also lead to the mobilisation of trace metals that can have direct toxic effects or can accumulate in the food chain (OSPARConvention for the Protection of the Marine Environment of the North-East Atlantic, which was adopted at Paris on 22 September 1992, 2007). This may pose an indirect hazard for human health and life.
Moreover, the other contaminants that can be present in the CO2 streamA flow of substances resulting from CO2 capture processes, or which consists of a sufficient fraction of CO2 and sufficiently low concentrations of other substances to meet specifications of streams permitted for long term geological storage could increase the negative impact of a CO2Carbon dioxide leak, but this issue is not yet wellManmade hole drilled into the earth to produce liquids or gases, or to allow the injection of fluids understood and more research is required.
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Fig. 3-4: pH values at 5 m depth (a) and 10 m depth (b) (Espa et al., 2010). |
The ability of the marine ecosystem to recover after a leakage(in CO2 storage) The escape of injected fluid from the storage formation to the atmosphere or water column has been stopped is an issue that needs more research and can only be fully assessed on a site-specific basis. It is thought though that shallow ecosystems recover faster than deep ecosystems (OSPARConvention for the Protection of the Marine Environment of the North-East Atlantic, which was adopted at Paris on 22 September 1992, 2007).