Monitoring Saharan groundwater resources overlying a terrestial CCS site
Sorensen, James; Darling, George; Newell, Andrew. 2012 Monitoring Saharan groundwater resources overlying a terrestial CCS site. [Poster] In: Ineson Meeting: Groundwater and Energy, London, 17th October 2012. (Unpublished)Before downloading, please read NORA policies.
The In Salah Joint Venture is an industrial scale CCS research project at the Krechba gas field in Algeria, with the aim of storing 17 million tonnes of CO2 over the next 20 years. CO2 is removed from the abstracted gas and reinjected as a supercritical fluid into brines within the sandstone reservoir, which is capped by 900 m of Carboniferous mudstones. This is overlain by the confined Continental Intercalaire (CI) one of the world’s largest groundwater systems, which extends across Algeria, Libya and Tunisia, and is the only source of fresh water in many areas. Any leakage from the injection reservoir presents a potential hazard to this non-renewable resource and could result in an adverse effect on the water quality. Therefore a comprehensive, multi-disciplinary program has been established to monitor the CO2 plume within the storage complex and also ensure the integrity of the legacy gas wells and cap-rock. From our perspective, the program included the drilling and monitoring of five boreholes within the CI aquifer. Geochemical sampling from these boreholes is undertaken annually and the results are validated against a previous baseline survey for significant differences. Potential induced changes in chemistry may include higher concentrations of dissolved CO2/CH4, lower pH, higher TDS, elevated heavy metals and a reduction in dissolved O2. Water levels are also monitored half-hourly using pressure transducers to detect any aquifer pressurisation. There is no current evidence of any leakage of CO2 into the CI aquifer.
|Item Type:||Conference or Workshop Item (Poster)|
|Programmes:||BGS Programmes 2010 > Groundwater Science|
|Additional Keywords:||GroundwaterBGS, Groundwater, Groundwater resources, Groundwater monitoring|
|Date made live:||25 Oct 2012 15:28|
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