Abstract
In this study, we examined the groundwater monitoring data from the national groundwater monitoring station in Andong at the southeastern part of South Korea. The monitoring station is located in Cretaceous Gyeongsang sedimentary basin which has been considered for geologic CO2 storage in South Korea. Groundwater at the station is characteristically CO2-rich and typically shows a vertical stratification of water chemistry with depth. Groundwater at shallow depths (< 7 m deep) has low electrical conductivity (EC) values, ca. 280 μS/cm, while deeper groundwater (down to 70 m below the land surface) has higher EC values (up to 3,900 μS/cm). The EC logging in the well also shows the significant stepwise variation of the EC values with depth. The results of the well logging of physicochemical data in conjunction with the borehole imaging using a nano camera and the hydrochemical analysis of groundwater indicate that the observed vertical stratification in the well is the result of physicochemical changes of CO2-rich groundwater with high EC values via CO2 outgassing and associated precipitation of minerals during ascending. The results of the present study demonstrate that, provided there is vertical stratification of EC in a monitoring well or in a storage site, geochemical monitoring at shallow depths may lead to a bias in the monitoring results. Our results suggest the following implications: 1) careful baseline data analysis at several depths is required for precise groundwater monitoring in CO2 storage sites and 2) based on the good understanding of hydrogeological condition, proper sites and depths of geochemical monitoring should be selected.
| Original language | English |
|---|---|
| Pages (from-to) | 3863-3869 |
| Number of pages | 7 |
| Journal | Energy Procedia |
| Volume | 114 |
| DOIs | |
| Publication status | Published - 2017 |
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Keywords
- CO-rich water
- electric conductivity
- geologic carbon storage
- groundwater monitoring
- vertical stratification
ASJC Scopus subject areas
- Energy(all)
Cite this
Vertical Hydrochemical Stratification of Groundwater in a Monitoring Well : Implications for Groundwater Monitoring on CO2 Leakage in Geologic Storage Sites. / Ryuh, Yon Gyung; Do, Hyun Kwon; Kim, Kyoung Ho; Yun, Seong Taek.
In: Energy Procedia, Vol. 114, 2017, p. 3863-3869.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Vertical Hydrochemical Stratification of Groundwater in a Monitoring Well
T2 - Implications for Groundwater Monitoring on CO2 Leakage in Geologic Storage Sites
AU - Ryuh, Yon Gyung
AU - Do, Hyun Kwon
AU - Kim, Kyoung Ho
AU - Yun, Seong Taek
PY - 2017
Y1 - 2017
N2 - In this study, we examined the groundwater monitoring data from the national groundwater monitoring station in Andong at the southeastern part of South Korea. The monitoring station is located in Cretaceous Gyeongsang sedimentary basin which has been considered for geologic CO2 storage in South Korea. Groundwater at the station is characteristically CO2-rich and typically shows a vertical stratification of water chemistry with depth. Groundwater at shallow depths (< 7 m deep) has low electrical conductivity (EC) values, ca. 280 μS/cm, while deeper groundwater (down to 70 m below the land surface) has higher EC values (up to 3,900 μS/cm). The EC logging in the well also shows the significant stepwise variation of the EC values with depth. The results of the well logging of physicochemical data in conjunction with the borehole imaging using a nano camera and the hydrochemical analysis of groundwater indicate that the observed vertical stratification in the well is the result of physicochemical changes of CO2-rich groundwater with high EC values via CO2 outgassing and associated precipitation of minerals during ascending. The results of the present study demonstrate that, provided there is vertical stratification of EC in a monitoring well or in a storage site, geochemical monitoring at shallow depths may lead to a bias in the monitoring results. Our results suggest the following implications: 1) careful baseline data analysis at several depths is required for precise groundwater monitoring in CO2 storage sites and 2) based on the good understanding of hydrogeological condition, proper sites and depths of geochemical monitoring should be selected.
AB - In this study, we examined the groundwater monitoring data from the national groundwater monitoring station in Andong at the southeastern part of South Korea. The monitoring station is located in Cretaceous Gyeongsang sedimentary basin which has been considered for geologic CO2 storage in South Korea. Groundwater at the station is characteristically CO2-rich and typically shows a vertical stratification of water chemistry with depth. Groundwater at shallow depths (< 7 m deep) has low electrical conductivity (EC) values, ca. 280 μS/cm, while deeper groundwater (down to 70 m below the land surface) has higher EC values (up to 3,900 μS/cm). The EC logging in the well also shows the significant stepwise variation of the EC values with depth. The results of the well logging of physicochemical data in conjunction with the borehole imaging using a nano camera and the hydrochemical analysis of groundwater indicate that the observed vertical stratification in the well is the result of physicochemical changes of CO2-rich groundwater with high EC values via CO2 outgassing and associated precipitation of minerals during ascending. The results of the present study demonstrate that, provided there is vertical stratification of EC in a monitoring well or in a storage site, geochemical monitoring at shallow depths may lead to a bias in the monitoring results. Our results suggest the following implications: 1) careful baseline data analysis at several depths is required for precise groundwater monitoring in CO2 storage sites and 2) based on the good understanding of hydrogeological condition, proper sites and depths of geochemical monitoring should be selected.
KW - CO-rich water
KW - electric conductivity
KW - geologic carbon storage
KW - groundwater monitoring
KW - vertical stratification
UR - http://www.scopus.com/inward/record.url?scp=85029657841&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85029657841&partnerID=8YFLogxK
U2 - 10.1016/j.egypro.2017.03.1518
DO - 10.1016/j.egypro.2017.03.1518
M3 - Article
AN - SCOPUS:85029657841
VL - 114
SP - 3863
EP - 3869
JO - Energy Procedia
JF - Energy Procedia
SN - 1876-6102
ER -