EGU21-16366, updated on 04 Mar 2021
https://doi.org/10.5194/egusphere-egu21-16366
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Multiple DNA-tracer transport approach for determining aquifer matrix properties in a laboratory 3D aquifer sand tank: a methodical perspective

Swagatam Chakraborty1, Chamath Arachchilage2, Rayan Hamza Mohamed Elhaj2, Jan Willem Foppen2,3, Thom Bogaard3, and Jack Schijven4
Swagatam Chakraborty et al.
  • 1Department of Earth Sciences, Faculty of Geosciences, Universiteit Utrecht, Utrecht, the Netherlands
  • 2IHE-Delft, Institute for Water Education, Delft, the Netherlands
  • 3Faculty of Civil Engineering and Geosciences, Delft University of Technology (TUDelft), Stevinweg 1, 2628 CN Delft, the Netherlands
  • 4Department of Statistics, Informatics and Modelling, National Institute of Public Health and the Environment, P.O.Box 1, 3720 BA Bilthoven, the Netherlands

Use of environmental or artificial tracers has been an effective approach to characterize groundwater flow and solute transport, tracking pollutant migration and determine travel time. However, availability of a distinctive number of tracers, variability in interaction with the aquifer matrix, and analytical detection limits are namely few of the significant concerns to be addressed and which led us to focus on employing novel DNA tracers.

Besides the quality of being unique, improbably prevalent in nature and environmentally friendly, DNA tracers can be synthesized virtually in infinite numbers of distinct sequences, rendering them a potential candidate for multi-tracer applications for subsurface and groundwater flow characterization. Studies have already demonstrated the potential of DNA tracing in groundwater studies but a blueprint for methodical application and analysis is required.

In this study, we investigate the applicability of DNA tracers in determining hydraulic parameters of a natural aquifer, such as, hydraulic conductivity, effective porosity, dispersivity, and travel time, the most significant characters of a matrix, influencing solute or pollutant transport. In addition, we aim to leverage the applicability of the tracers in terms of minimizing the uncertainty in estimating the parameters.

In order to capitalize on these advantages of DNA tracers with the aim of addressing the aforementioned objectives, this research focuses on employing multiple dsDNA (ds=double stranded) tracers in a 1.3 m long three-dimensional sand-filled aquifer tank. Under forced-gradient water flow conditions, distinctly sequenced, monodispersed dsDNA tracers are instantaneously injected through injection wells, taking into account different scenarios. The scenarios consider different configurations of injection and sampling strategies. Samples collected periodically were subjected to quantitative polymerase chain reaction (qPCR) for DNA concentration estimation. All the silica-encapsulated DNA particles were comparable in size and surface properties.

Individual breakthrough curves from each of the scenarios are carefully analysed for determining water flow and hydraulic properties. In addition, the experiments producing multiple breakthrough curves are cumulatively analysed for obtaining a minimal uncertainty for the parameter estimations.

How to cite: Chakraborty, S., Arachchilage, C., Elhaj, R. H. M., Foppen, J. W., Bogaard, T., and Schijven, J.: Multiple DNA-tracer transport approach for determining aquifer matrix properties in a laboratory 3D aquifer sand tank: a methodical perspective, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-16366, https://doi.org/10.5194/egusphere-egu21-16366, 2021.

Corresponding presentation materials formerly uploaded have been withdrawn.