Assessment of shallow aquifer remediation capacity under different groundwater management conditions in CGS field
- PDF / 12,651,254 Bytes
- 17 Pages / 595.276 x 790.866 pts Page_size
- 94 Downloads / 213 Views
ORIGINAL PAPER
Assessment of shallow aquifer remediation capacity under different groundwater management conditions in CGS field Shanghai Du 1,2,3 & Liange Zheng 3 & Wenjing Zhang 1,2
Received: 23 June 2015 / Accepted: 22 April 2016 # Saudi Society for Geosciences 2016
Abstract Because of unknown faults and fractures in the overlying rock, CO2 stored deep underground may move upward, and the intrusion may impact shallow groundwater quality. After leakage of CO2 has ceased, the affected aquifer may show remediation capacity under natural conditions and injections and extractions. In this study, the reactive transport modeling software TOUGHREACT was used to simulate the remediation capacity of a study aquifer. The simulation results show that the intrusion of leaked CO2 would decrease the pH of the target aquifer and trigger the dissolution of calcite minerals. After CO2 leakage has ceased, the pH would increase as would the concentration of Ca because of the dissolution of calcite along the flow path. Scenario simulation results of amelioration of groundwater quality by water injection and extraction show that single injection is the best option and a combination approach of injection and extraction could
* Wenjing Zhang [email protected] 1
Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun 130021, China
2
Institute of Water Resources and Environment, Jilin University, Changchun, China
3
Earth Science Division, Lawrence Berkeley National Laboratory, Berkeley, USA
control the range of the affected area. The pH value should not be regarded as the single indicator for remediation capacity assessment. Parameter sensitive analysis results show that the rates of injection and extraction affect the repair results significantly. Keywords Carbon dioxide leakage . Groundwater . Remediation . Calcite
Introduction Carbon Dioxide Geological Storage (CGS) is one of the most effective methods of reducing the anthropogenic emissions of CO2 and mitigating global climate change (Bachu 2000; Su et al. 2013; Du et al. 2015; Zhao et al. 2015). Because of the unknown faults and fractures in overlying rock, deep-stored CO2 may move upward, and the intrusion impacts shallow groundwater quality (Smyth et al. 2009; Siirila et al. 2012; Yang et al. 2015; Zheng et al. 2015). According to the published research, leaked CO 2 could decrease the pH of shallow groundwater, changing the controlling conditions of mineral dissolution/ precipitation and adsorption/desorption, and thereby affecting the transport and transformation of metal species and organic matter in groundwater, and enhancing the risk of groundwater pollution (Zheng et al. 2009;
448
Arab J Geosci (2016) 9:448
Page 2 of 17
Fig. 1 Field test area and well locations (IW injection well, PW pumping well, MW monitoring well, BG background monitoring well)
Lemieux However, lation of presence
Table 1
Hydrogeology parameters used in the models
Parameters
Values
Porosity Permeability (m2)
0.3 1.44 × 10−11
Data Loading...
