Potential influence of CO2 release from a carbon capture storage site on release of trace metals from marine sediment

Evaluation of the threat of marine CO2 leakage-associated acidification on the toxicity of sediment metals to juvenile bivalves

“…Hence, tests of elutriates are further justified in the context of CO 2 escape and could mimic sediment re-suspension scenarios as a consequence of flows of CO 2 through the sediment during leak events (Payan et al, 2012). To the best of our knowledge, accidental CO 2 leakage from storage sites in sub-seabed formation has not been reported.…”

“…The pH is one of the main environmental factors that determine the organic and inorganic speciation of the metals present in marine ecosystems (Millero et al, 2009). Recent studies have postulated that the acidification processes would affect the stability of metals trapped on marine sediments (Ardelan et al, 2009;De Orte et al, 2014b;Payan et al, 2012;Roberts et al, 2013), leading to increases in the concentrations of metals dissolved in the overlying water (Basallote et al, 2014;De Orte et al, 2014a), which could increase the toxic effects on the surrounding biota. The sediment quality is expected to be affected by pH decreases, leading to increases in the toxicity of sediments that would not produce toxic effects at the natural environmental pH.…”

The Use of Leaching Tests to Assess Metal Release from Contaminated Marine Sediment under CO2 Leakages from CCS

“…The evaluation of the release of constituents from solid matrices (sediment, dredged material or waste materials) has been developed by leaching tests simulating a high number of different conditions [10,11]. The leaching process is very complex and one single test cannot provide a complete understanding of the heavy metal mobility.…”

Development of detection and monitoring techniques of CO2 leakage from seafloor in sub-seabed CO2 storage

“…If CO 2 sequestered in the sub-seabed leaks into the ocean or into pore water, the leaked CO 2 will react with the sediment and dissolve metals contained in it, after which the dissolved metals will diffuse into the seawater. In order to investigate the release of metals from sediment due to CO 2 leakage at a storage site, Payán et al (2012) carried out laboratory leaching tests of metals from contaminated marine sediment and pointed out the possibility of trace metal leaching in an acidified seawater environment. Since the difference between the concentration of metals in typical seawater and that in sediment is extremely large, changes in the concentration of metals in seawater can serve as a highly sensitive indicator for detecting leaked CO 2 (either gaseous or liquid).…”