Beth L. Parker, PhD, LEL
Dr. Beth Parker is a hydrogeologist who has made exceptional contributions to the science and practice of Contaminant Hydrogeology. This science concerns the occurrence, migration and fate of contamination in the groundwater component of the hydrological cycle. Dr. Parker has achieved strong national and international recognition for her contributions to the science and technologies important to the understanding and remediation of contaminated groundwater. She is the most cited Canadian under the age of 60 for papers concerning groundwater contamination. She is one of the most cited internationally and most frequently invited speakers internationally for presentations about groundwater contamination research. In addition to the strong support from the Canadian Government and Industry as part of her Industrial Research Chair for fractured rock contamination hydrology, she draws substantial research funds from international sources including the USA, Sweden, China and Brazil and is sought after as a collaborator internationally. Dr. Parker has advanced a particular and original conceptual view concerning groundwater contamination in fractured geologic media, focusing on sedimentary rock and clayey aquitards, and has established the validity of this view by invention and application of a suite of novel and powerful methods to acquire field data for creation and validation of conceptual models.
Dr. Parker received her PhD degree in 1996. Dr. Parker has published >120 papers in refereed journals, has >10 additional papers submitted and currently in review and has produced many non-refereed papers. Of these published and in review referred papers, most are in ‘fractured rock hydrogeology’ with relevance to contaminant transport and fate. Her publications are widely recognized. According to Google Scholar, she is in the top tier of those in the groundwater contamination domain. Since 2012, she has published an average of nearly 10 journal articles per year, a productivity level that is the largest among all Canadian and international academics who are comparable based on specialization in the physical aspects groundwater science and engineering (separate from the chemical and microbiological specializations). Dr. Parker has been an invited keynote speaker at >50 conferences distributed across many countries (USA, Canada, Brazil, China, Italy, Sweden, Switzerland, Denmark). She has many international collaborations as indicated by her publications. Of her published and submitted papers, nearly 30% have co-authors from beyond Canada (USA, Spain, Italy, Switzerland). As supervisor and co-supervisor of graduate students, Dr. Parker has produced >35 MSc and >5 PhD graduates.
Dr. Parker’s accomplishments are a combination of conceptual models, methods, and technologies that have ‘high resolution contaminant hydrogeology’ as their common denominator. She is the Director of the G360 Institute for Groundwater Research at the University of Guelph. This Institute, which Dr. Parker founded 10 years ago, has grown to a team of ~50 people including research associates, post-doctoral fellows, graduate students, and technicians who support projects in many countries. This Institute is now one of the largest University based groundwater groups in Canada in terms of funding, staff, and number of students. She is the principal investigator for research funding from more than a dozen government and industry sources totaling >$4 million annually that supports the large research team that she directs. Dr. Parker is also co-Director of the longest standing industry-funded independent research program in Canada, the University Consortium for Field-Focused Groundwater Contamination Research (theuniversityconsortium.org).
Dr. Parker is in the top echelon of academics who are advancing fractured-media hydrogeology, including bedrock aquifers and clayey aquitards. Although she is an academic, she is heavily involved with advancing knowledge and technologies most relevant to real problems at contaminated sites in the United States, Canada, and several other countries including Brazil, Germany, Sweden, and others, and her advances are rapidly influencing professional practice. Her unique contributions centre on the incorporation of molecular diffusion into the framework for assessing the behaviour of many types of contaminants in groundwater, where the interplay between advection and diffusion is the key to rigorous understanding of contaminant transport and fate with emphasis on fractured porous sedimentary rock. This theme is at the heart of nearly all her publications regardless of the type of geologic media. As sedimentary bedrock aquifers become increasingly important in water security, the need for better understanding fractured rock has become globally important for cities, municipalities, brownfields development, agriculture, manufacturing, oil and gas development, mining, nuclear plant decommissioning, geothermal energy, and beyond. Although the research mostly concerns fundamental aspects of contaminant behaviour at the high resolution field scales, broad practical usefulness of her research is evident from the fact that her research program is funded from many diverse sources in addition to the Canadian Goverment (NSERC), including large multinational companies with exceptionally complex contaminated sites, petroleum companies, chemical companies, cities and municipalities, environmental consulting firms, the US military, a water bottling company and even a citizen’s group seeking safe drinking water.
Dr. Parker’s research emphasizes interactions between contaminant advection due to groundwater flow and molecular diffusion, including the effects of forward diffusion on plume attenuation and back diffusion on source and plume persistence and as an impediment to remediation. This original research path began with her PhD thesis, the first paper from which (Parker BL, Gillham RW, Cherry JA. 1994. Diffusive disappearance of immiscible-phase organic liquids in fractured geologic media, Groundwater 32(5): 805-820) has >100 citations in the scientific literature (according to Google Scholar). Dr. Parker was the first to show the importance of back diffusion of contaminant mass stored in low permeability layers and aquitards on the persistence of plumes in aquifers using high-resolution site datasets combined with mathematical modeling. Back diffusion is now widely accepted as a cause of plume longevity and, in some situations, is the basis for technical impracticability. Her emphasis on the development of process-based conceptual models for understanding contaminant behaviour began in the 1990s as she focused primarily on chlorinated solvents as dense non-aqueous phase liquids (DNAPLs) in source zones and on the solute plumes that form downgradient in non-indurated geologic deposits, such as fractured and unfractured clayey aquitards and heterogeneous sandy aquifers. These studies included controlled contaminant-release experiments and intensive investigations at decades-old contaminated sites.
Over the past 15 to 20 years, Dr. Parker’s research emphasis shifted to chlorinated solvents in fractured sedimentary rock, mostly sandstone, shale, limestone, and dolostone, and the contaminant categories have broadened to include metals such as hexavalent chromium, agricultural contaminants such as nitrate, chloride, toluene, methane, and human pathogens. Intensive, multidisciplinary collaborative studies, led by Dr. Parker, of many contaminated bedrock sites have resulted in a comprehensive methodology for acquiring high-resolution data from fractured porous media (the field Discrete Fracture Network (DFN) approach) that incorporates techniques from geology, hydrogeology, geophysics, and environmental chemistry. This methodology includes the use of core sampling and contaminant analysis of core samples to delineate contamination in aquitards and in the rock matrix in fractured rock (e.g., CORE DFN™) as well as detailed methods for assessing the groundwater flow systems. Most recently, the methodology has incorporated the use of fiber optic cables and heating cables for high resolution temporal monitoring of temperature in rock boreholes in combination with FLUTe flexible liners to position the cables against the borehole walls, detect active flow in fractures, and prevent the vertical cross-flow in the boreholes that disrupts the flow system and biases/ obscures the resulting interpretations. The methodology provides robust data sets to existing DFN mathematical models for simulations of groundwater flow and contaminant plume evolution in fractured sedimentary bedrock. Much of this involves innovations incorporated into three patents on which Dr. Parker is a co-inventor, with two additional patents submissions currently in progress.