Research Fellow: Richard Hoffmann 
Profile
hosted at Hydrogeology & Environmental Geology, University of Liege, Belgium
Supervisors
Alain Dassargues – University of Liege
Pascal Goderniaux – University of Mons
co-supervisors
Frederic Nguyen – University of Liège
Thomas Hermans – Ghent University
Secondments
NRGI Hyderabad, BRGM – 6 months (2018)
Research Center Jülich – 3 months (2019)
Research objectives
1) Characterization of preferential flow paths with multiple-scale transport modeling for heterogenous porous and fractured media using innovative joint heat and solute tracer tests.
2) Assessing the impact of preferential flow paths and quantify the associated uncertainty in model predictions by using a dual-domain approach and Bayesian Evidential Learning (BEL).
Tasks and methodology
Tasks: Carrying out a multi-tracer approach with multiple well injection and pumping tests in alluvial sediments and fractured rocks. Field tests measurements will be complemented by Distributed Temperature Sensing (DTS) and geophysical imaging.
Methodology: Using the complementary behavior of multiple tracers based on different diffusion coefficients and sensitivities to preferential flow paths and matrix diffusion. Uncertainty will be addressed using the BEL method.
Data & datasets
Datasets created during the research project are to be found on the H+ database.
Access to dataset used in the article published in Geophysical Research Letters (2020)
Dissemination and communication
2020
Publication in Geophysical Research Letters (August 2020): “Continuous dissolved gas tracing for fracture-matrix exchange”
https://doi.org/10.1029/2020GL088944
2019
Presentation at the AGU Fall Meeting 2019, San Francisco (USA): “The potential of temperature and dissolved gas as smart tracers for process-based heterogeneity characterization“
Publication in frontiers in Earth Sciences (May 2019): “Heterogeneity and Prior Uncertainty Investigation Using a Joint Heat and Solute Tracer Experiment in Alluvial Sediments”
https://doi.org/10.3389/feart.2019.00108
Presentation for the 10th International Groundwater Quality Conference (Liege, Belgium): “Dissolved Gas, Heat and Cold Water as innovative smart tracers for transports heterogeneity characterisationin fractured media“
June 4th: Oral presentation at the 24th H+ Network Meeting: “Cold water injections in South india – An innovative smart tracer technique for hot fractured aquifers”
Presentation for the IAH Congress – Groundwater management and governance coping with water scarcity (Malaga, Spain): “Cold water injections as innovative smart tracer technique in hot fractured aquifers“
Poster for the IAH Congress – Groundwater management and governance coping with water scarcity (Malaga, Spain): “Modeling a heat tracer test in alluvial sediments using Monte Carlo: on the importance of the prior“
2018
Presentation at the 45th IAH Congress (Korea): “Fractured aquifer heterogeneity characterization for advanced transport modelling based on multiple single fracture tracer tests”
Presentation at the 6th International Geologica Belgica Meeting (Leuven, Belgium): “The double porosity of the chalk and its influence on solute and heat transport“
Poster presented during the 4th Cargèse Summer School :Multi scale transport modelling in heterogenous porous and fractured media
Presentation for the Computational Methods in Water Resources XXII (Saint-Malo, France): “Prior uncertainty investigation of density-viscosity dependent joint transport of heat and solute in alluvial sediments“
Glossary
BEL: Bayesian Evidential Learning relies on a limited number of Monte Carlo simulations sampling the prior distribution of model parameters to analyze the global sensitivity of parameters
DTS: Distributed Temperature Sensing serves for recording temperature as continuous profile along an optical sensor cable.