A model of isotope transport in the unsaturated zone, case study
DOI:
https://doi.org/10.14311/AP.2022.62.0427Keywords:
Richards' equation, unsaturated zone, groundwater flow in unsaturated zone, solute transportAbstract
This work deals with a groundwater flow and solute transport model in the near-surface (predominantly unsaturated) zone. The model is implemented so that it allows simulations of contamination transport from a source located in a geological environment of a rock massif. The groundwater flow model is based on Richards’ equation. Evaporation is computed using the Hamon model. The transport model is able to simulate advection, diffusion, sorption and radioactive decay. Besides the basic model concept, the article also discusses potential cases that could lead to non-physical solutions. On three selected examples, which include, for example, rapidly changing boundary conditions, the article shows the solvability of such cases with the proposed model without unwanted effects, such as negative concentrations or oscillations of solution, that do not correspond to inputs.
Downloads
References
P. O. Johansson. Description of surface hydrology and near-surface hydrogeology at Forsmark. Site descriptive modelling, SDM-Site Forsmark. Tech. Rep. SKB R-08-08, Swedish Nuclear Fuel and Waste Management Co, Stockholm, Sweden, 2008. https://www.skb.com/publication/1853247/R-08-08.pdf.
K. Werner, M. Sassner, E. Johansson. Hydrology and near-surfacehydrogeology at Forsmark – synthesis for the SR-PSU project. SR-PSU Biosphere. Tech. Rep. SKB R-13-19, Swedish Nuclear Fuel and Waste Management Co, Stockholm, Sweden, 2013. https://www.skb.com/publication/2477948/R-13-19.pdf.
E. Jutebring Sterte, E. Johansson, Y. Sjöberg, et al. Groundwater-surface water interactions across scales in a boreal landscape investigated using a numerical modelling approach. Journal of Hydrology 560:184–201, 2018. https://doi.org/10.1016/j.jhydrol.2018.03.011.
P. A. Ekström. Pandora – a simulation tool for safety assessments. Technical description and user’s guide. Tech. Rep. SKB R-11-01, Swedish Nuclear Fuel and Waste Management Co, Stockholm, Sweden, 2010. https://www.skb.com/publication/2188873/R-11-01.pdf.
C. Yu, E. Gnanapragasam, J.-J. Cheng, et al. User’s Manual for RESRAD-OFFSITE Code Version 4. United States Nuclear Regulatory Commission, Argonne National Laboratory, USA, 2020, https://resrad.evs.anl.gov/docs/RESRAD-OFFSITE_UsersManual.pdf.
J. Šimůnek, M. Šejna, H. Saito, et al. The Hydrus-1D Software Package for Simulating the Movement of Water, Heat, and Multiple Solutes in Variably Saturated Media, Version 4.17, HYDRUS Software Series 3. Department of Environmental Sciences, University of California Riverside, Riverside, California, USA, 2013, https://www.pc-progress.com/Downloads/Pgm_hydrus1D/HYDRUS1D-4.17.pdf.
C. I. Steefel, C. A. J. Appelo, B. Arora, et al. Reactive transport codes for subsurface environmental simulation. Computational Geosciences 19(3):445–478, 2015. https://doi.org/10.1007/s10596-014-9443-x.
J. Březina, M. Hokr. Mixed-hybrid formulation of multidimensional fracture flow. In I. Dimov, S. Dimova, N. Kolkovska (eds.), Numerical Methods and Applications. NMA 2010. Lecture Notes in Computer Science, vol. 6046. Springer, Berlin, Heidelberg, 2011. https://doi.org/10.1007/978-3-642-18466-6_14.
J. Březina, J. Stebel, D. Flanderka, et al. Flow123d, version 2.2.1. User Guide and Input Reference. Technical university of Liberec, Faculty of mechatronics, informatics and interdisciplinary studies, Liberec, 2018, https://flow.nti.tul.cz/packages/2.2.1_release/flow123d_2.2.1_doc.pdf.
M. Hokr, H. Shao, W. P. Gardner, et al. Real-case benchmark for flow and tracer transport in the fractured rock. Environmental Earth Sciences 75(18):1273, 2016. https://doi.org/10.1007/s12665-016-6061-z.
W. R. Hamon. Estimating potential evapotranspiration. Journal of the Hydraulics Division 87(3):107–120, 1961. https://doi.org/10.1061/JYCEAJ.0000599.
T. Vogel, K. Huang, R. Zhang, M. T. van Genuchten. The HYDRUS code for simulating one-dimensional water flow, solute transport, and heat movement in variably-saturated media, Version 5.0. Research Report No 140. U.S. Salinity Laboratory, USDA, ARS, Riverside, CA, 1996.
K. Zhang, Y.-S. Wu, J. E. Houseworth. Sensitivity analysis of hydrological parameters in modeling flow and transport in the unsaturated zone of Yucca Mountain, Nevada, USA. Hydrogeology Journal 14(8):1599–1619, 2006. https://doi.org/10.1007/s10040-006-0055-y.
L. A. Richards. Cappillary conduction of liquids through porous mediums. Physics 1(5):318–333, 1931. https://doi.org/10.1063/1.1745010.
M. T. van Genuchten. A closed-form equation for predicting the hydraulic conductivity of unsaturated soils. Soil Science Society of America Journal 44(5):892–898, 1980. https://doi.org/10.2136/sssaj1980.03615995004400050002x.
M. G. Schaap, F. J. Leij, M. T. van Genuchten. rosetta: a computer program for estimating soil hydraulic parameters with hierarchical pedotransfer functions. Journal of Hydrology 251(3-4):163–176, 2001. https://doi.org/10.1016/S0022-1694(01)00466-8.
M. A. Celia, E. T. Bouloutas, R. L. Zarba. A general mass-conservative numerical solution for the unsaturated flow equation. Water Resources Research 26(7):1483–1496, 1990. https://doi.org/10.1029/wr026i007p01483.
E. Juranová, E. Hanslík, S. Dulanská, et al. Sorption of anthropogenic radionuclides onto river sediments and suspended solids: dependence on sediment composition. Journal of Radioanalytical and Nuclear Chemistry 324(3):983–991, 2020. https://doi.org/10.1007/s10967-020-07174-w.
Historical data: Weather: Prague Clementinum. CHMI portal. [2020-11-02], http://portal.chmi.cz/historicka-data/pocasi/praha-klementinum?l=en#.
Downloads
Published
Issue
Section
License
Copyright (c) 2022 Josef Chudoba, Jiřina Královcová, Jiří Landa, Jiří Maryška, Jakub Říha
This work is licensed under a Creative Commons Attribution 4.0 International License.
How to Cite
Accepted 2022-05-31
Published 2022-08-31
