Quantifying Three-Dimensional Matrix Diffusion Effects on Plume Front Retardation

Tuesday, September 24, 2013: 1:50 p.m.
Barry Brouwers , Matrix Solutions Inc., Breslau, ON
Paul Martin , Matrix Solutions Inc., Breslau, ON, Canada
Daron Abbey , Matrix Solutions Inc., Breslau, ON
Steven W. Chapman, M.Sc., P.Eng. , School of Engineering, University of Guelph, Guelph, ON, Canada
Beth L. Parker, Ph.D. , School of Engineering, G360, University of Guelph, Guelph, ON, Canada
John A. Cherry, Ph.D. , School of Engineering, University of Guelph, Guelph, ON, Canada

It is well accepted that matrix diffusion effects on transport of contaminants through fractured media results in an effective retardation of plume migration.  Discrete Fractured Network (DFN) modelling representations for plume migration in fractured rock are typically accomplished using a two-dimensional approach.  While this approach is the limit of what is practical at the plume scale for many sites that have ubiquitous fracturing, it is expected that the effective plume retardation within such simulations will underestimate the rate of retardation that occurs in the field.  To better quantify the degree of enhanced retardation within the natural environment, three-dimensional discrete fracture modelling was undertaken.  For this approach, the discrete fracture flow and contaminant transport is accomplished by superimposing two-dimensional plane elements onto the three-dimensional mesh that represents the rock matrix, and incorporating a detailed level of distretization away from this fracture-matrix block interface to represent steep and variable diffusion profiles.  Insights gained through this detailed numerical modelling provide a better understanding toward the prediction of plume-scale migration rates that appropriately account for matrix diffusion and the apparent plume front retardation.

Barry Brouwers, Matrix Solutions Inc., Breslau, ON
Barry Brouwers is a Modelling Specialist with Matrix Solutions Inc. Barry graduated from the University of Waterloo with Bachelor’s and Master’s degrees in civil engineering. Since graduation, Barry has been working within the groundwater industry as a groundwater modelling specialist developing models primarily for source water protection and groundwater remediation assessment. His professional interests include: watershed scale modeling, source water protection, integrated groundwater-surface water modelling, assessing climate change impacts to water resources, and prediction uncertainty analysis.


Paul Martin, Matrix Solutions Inc., Breslau, ON, Canada
Paul Martin is a Principal Hydrogeologist and Professional Engineer with Matrix Solutions. He holds a bachelor’s degree in Civil Engineering and a master’s degree in Earth Science from the University of Waterloo. Over the last 20-years Martin has worked on consulting projects ranging from water resources characterization to contaminant impact evaluation and remediation.


Daron Abbey, Matrix Solutions Inc., Breslau, ON
Daron Abbey is a Senior Hydrogeologist and Professional Geoscientist with Matrix Solutions Inc. Daron works out of Matrix’s Waterloo, Ontario office and completed his Master of Science in Earth Science at Simon Fraser University in Burnaby, BC. In the last 12 years he has completed numerous water supply and watershed management projects developing and applying conceptual and numerical models to support decisions making for municipalities, conservation authorities, provincial government, and commercial clients. A recent focus of this work includes projects related to decision making using uncertainty analysis for remediation of contaminated sites.


Steven W. Chapman, M.Sc., P.Eng., School of Engineering, University of Guelph, Guelph, ON, Canada
Steven Chapman is a Senior Research Engineer/Hydrogeologist in the G360 Centre for Applied Groundwater Research in the School of Engineering at the University of Guelph. He is a Professional Engineer (Civil) with an M.Sc. from the University of Waterloo (Earth Sciences). Chapman has more than 15 years of hydrogeologic experience. His research focuses on contaminant behavior in unconsolidated porous media and sedimentary rock, involving high resolution site characterization at industrial and research sites and numerical modeling, with a focus on the role of diffusion including impacts on remediation performance.


Beth L. Parker, Ph.D., School of Engineering, G360, University of Guelph, Guelph, ON, Canada
Beth Parker, Ph.D., University of Guelph Professor in the School of Engineering and Director of the G360 Centre for Applied Groundwater Research, has more than 30 years of experience investigating subsurface contamination at numerous sites around the world, using high resolution data sets for site conceptual model development and testing. Her current research activities emphasize developing improved field and laboratory methods for characterizations and monitoring of industrial contaminants in sedimentary rocks, clayey deposits, and sandy aquifers, and focus on the effects of diffusion in low permeability zones, plume attenuation, and hydrogeologic controls on remediation.



John A. Cherry, Ph.D., School of Engineering, University of Guelph, Guelph, ON, Canada
John Cherry holds geological engineering degrees from the University of Saskatchewan and the University of California Berkley, and earned a Ph.D. in hydrogeology from the University of Illinois. He joined the University of Waterloo in 1971, concentrating on field studies of the migration and fate of contaminants in groundwater, and continues research as a Distinguished Professor Emeritus. He has co-authored the textbook Groundwater and several chapters in the book on dense chlorinated solvents and other DNAPLs in groundwater. He is the Director of the University Consortium for Field-Focused Groundwater Contamination Research and is now based at the University of Guelph.