Monitoring nitrate reduction
- The mainly agricultural input of \(NO_{3}\)\(^{-}\) and compliance with drinking water guideline values pose major challenges for many water suppliers. Additionally, associated changes in hydrochemistry, especially concerning products of \(NO_{3}^{-}\) reduction (\(Fe^{2+/3+}\), \(Mn^{2+/4+}\), \(Ca^{2+}\), \(Mg^{2+}\), \(SO_4\)\(^{2-}\), \(HCO_3\)\(^-\)) and subsequent reactions, can have a major influence on mineral saturation states and well yield: well productivity can be strongly reduced by mineral precipitation and silting. To evaluate hydrogeochemical evolution and clogging potential for a given well field, thorough hydrochemical and geochemical investigations are required. Therefore, time-dependent and depth-specific ion concentrations in water samples (\(\it n\) = 818) were analysed in a catchment area of a waterworks in western Germany. The sediments of the aquifers were extensively investigated for their geochemistry (CS, scanning electron microscope, aqua regia digestion and dithionite solution; \(\it n\) = 253). In addition, PhreeqC was used to model saturation indices in order to identify possible mineral precipitation in the wells. Results show a high \(NO_{3}\)\(^{-}\) input into deep wells screened in Tertiary sediments due to an admixture of Quaternary groundwater. Directly at the Quaternary-Tertiary boundary, chemolithotrophic \(NO_{3}\)\(^{-}\) reduction consuming pyrite occurs. Protons released during the process are pH-buffered by dissolving carbonate minerals. Overall, the hydrochemistry and especially the saturation indices are strongly influenced by \(NO_{3}\)\(^{-}\) reduction and its degradation products. A change in well yield has not yet been observed, but future clogging by ochre formation or sintering cannot be excluded.
Author: | Felix OrtmeyerORCiDGND, Kristina VolkovaGND, Frank WisotzkyGND, Stefan WohnlichORCiDGND, Andre BanningORCiDGND |
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URN: | urn:nbn:de:hbz:294-97012 |
DOI: | https://doi.org/10.1007/s10661-021-08880-y |
Parent Title (English): | Environmental monitoring and assessment |
Subtitle (English): | hydrogeochemistry and clogging potential in raw water wells |
Publisher: | Springer Science + Business Media B.V. |
Place of publication: | Dordrecht |
Document Type: | Article |
Language: | English |
Date of Publication (online): | 2023/02/28 |
Date of first Publication: | 2021/02/05 |
Publishing Institution: | Ruhr-Universität Bochum, Universitätsbibliothek |
Tag: | Admixture; Germany; Hydrochemistry; Nitrate degradation; Well clogging |
Volume: | 193 |
Issue: | Article 112 |
First Page: | 112-1 |
Last Page: | 112-17 |
Note: | Dieser Beitrag ist auf Grund des DEAL-Springer-Vertrages frei zugänglich. |
Institutes/Facilities: | Institut für Geologie, Mineralogie und Geophysik |
Institut für Geologie, Mineralogie und Geophysik, Lehrstuhl Hydrogeologie | |
Dewey Decimal Classification: | Naturwissenschaften und Mathematik / Geowissenschaften, Geologie |
open_access (DINI-Set): | open_access |
faculties: | Fakultät für Geowissenschaften |
Licence (English): | Creative Commons - CC BY 4.0 - Attribution 4.0 International |