TY - JOUR
T1 - Assessing the transport of pharmaceutical compounds in a layered aquifer discharging to a stream
AU - Balbarini, Nicola
AU - Frederiksen, Majken
AU - Rønde, Vinni Kampman
AU - Møller, Ingelise
AU - Sonne, Anne Thobo
AU - McKnight, Ursula S.
AU - Pedersen, Jørn Kristian
AU - Binning, Philip John
AU - Bjerg, Poul Løgstrup
PY - 2020
Y1 - 2020
N2 - A groundwater plume containing high concentrations of pharmaceutical compounds, mainly sulfonamides, barbiturates and ethyl urethane, in addition to chlorinated ethenes and benzene was investigated. The contamination originating from a former pharmaceutical industry discharges into a multilayered aquifer system and a downgradient stream. In this study, geological and hydrogeological data were integrated into a numerical flow model to examine identified trends using statistical approaches, including principle component analysis and hierarchal cluster analysis. A joint interpretation of the groundwater flow paths and contaminant concentrations in the different compartments (i.e. groundwater and hyporheic zone) provided insight on the transport processes of the different contaminant plumes to the stream. The analysis of historical groundwater concentrations of pharmaceutical compounds at the site suggested these compounds are slowly degrading The pharmaceutical compounds migrate in both a deep semi-confined aquifer, as well as in the shallow unconfined aquifer, and enter the stream along a 2 km stretch. This contrasted with the chlorinated ethenes, which mainly discharge to the stream as a focused plume from the unconfined aquifer. The integrated approach developed here, combining groundwater flow modelling and statistical analyses of the contaminant concentration data collected in groundwater and the hyporheic zone, lead to an improved understanding of the observed distribution of contaminants in the unconfined and semi-confined aquifers, and thus to their discharge to the stream. This approach is particularly relevant for large and long-lasting contaminant sources and plumes, such as abandoned landfills and industrial production sites, where field investigations may be very expensive.
AB - A groundwater plume containing high concentrations of pharmaceutical compounds, mainly sulfonamides, barbiturates and ethyl urethane, in addition to chlorinated ethenes and benzene was investigated. The contamination originating from a former pharmaceutical industry discharges into a multilayered aquifer system and a downgradient stream. In this study, geological and hydrogeological data were integrated into a numerical flow model to examine identified trends using statistical approaches, including principle component analysis and hierarchal cluster analysis. A joint interpretation of the groundwater flow paths and contaminant concentrations in the different compartments (i.e. groundwater and hyporheic zone) provided insight on the transport processes of the different contaminant plumes to the stream. The analysis of historical groundwater concentrations of pharmaceutical compounds at the site suggested these compounds are slowly degrading The pharmaceutical compounds migrate in both a deep semi-confined aquifer, as well as in the shallow unconfined aquifer, and enter the stream along a 2 km stretch. This contrasted with the chlorinated ethenes, which mainly discharge to the stream as a focused plume from the unconfined aquifer. The integrated approach developed here, combining groundwater flow modelling and statistical analyses of the contaminant concentration data collected in groundwater and the hyporheic zone, lead to an improved understanding of the observed distribution of contaminants in the unconfined and semi-confined aquifers, and thus to their discharge to the stream. This approach is particularly relevant for large and long-lasting contaminant sources and plumes, such as abandoned landfills and industrial production sites, where field investigations may be very expensive.
KW - Pharmaceutical plume
KW - Groundwater-surface water interaction
KW - Integrated approach
KW - Groundwater modelling
KW - Principal component analyses and hierarchical cluster analysis
KW - Chlorinated ethenes
U2 - 10.1111/gwat.12904
DO - 10.1111/gwat.12904
M3 - Journal article
C2 - 31081137
VL - 58
SP - 208
EP - 223
JO - Ground Water
JF - Ground Water
SN - 0017-467X
IS - 2
ER -