Bernard Kueper

Bernard Kueper
Queen's University | QueensU · Department of Civil Engineering

About

114
Publications
10,317
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3,510
Citations
Citations since 2017
13 Research Items
778 Citations
2017201820192020202120222023050100150
2017201820192020202120222023050100150
2017201820192020202120222023050100150
2017201820192020202120222023050100150
Introduction

Publications

Publications (114)
Article
The development of a conceptual site model (CSM) is essential to support decision making for the investigation and remediation of contaminated sites, including sites impacted by dense non‐aqueous phase liquids (DNAPLs). Dynamic investigation strategies using high‐resolution site investigation tools can be used to increase the accuracy, and increase...
Article
There is a need for destructive technologies for per- and polyfluoroalkyl substances (PFAS) in soil. While planetary ball mill have been shown successful degradation of PFAS, there are issues surrounding scale up (maximum size is typically 0.5 L cylinders). While having lower energy outputs, horizontal ball mills, for which scale up is not a limiti...
Article
In this study, we have compared heat and solute transport in a discrete fracture using numerical modeling. Fracture aperture heterogeneity was described using geostatistical properties with fracture aperture means of up to 1,000 μm, variances of 10,000 µm² and isotropic correlation lengths up to 10 m. Groundwater flow in the matrix was assumed to b...
Article
The removal of dissolved volatile organic compounds (VOCs) from low-permeability lenses is important to limit back-diffusion at sites impacted by dense non-aqueous phase liquids (DNAPLs). In situ thermal treatment (ISTT) technologies have the potential to treat DNAPL-impacted sites by enhancing diffusion from low-permeability lenses during heating....
Article
Per- and polyfluoroalkyl substances (PFAS) are manmade, fluorinated organic chemicals which have been identified as persistent organic pollutants. PFAS have surface active properties that have made them suitable for applications in oil- and water-resistant products, as well as many firefighting foams. No on-site remediation strategies exist to trea...
Article
In situ thermal treatment (ISTT) technologies can be used to remove mass from non-aqueous phase liquid (NAPL) source zones. Ensuring the vaporization of NAPL and the capture of vapors are crucial, and numerical models are useful for understanding the processes that affect performance to help improve design and operation. In this paper, a two-dimens...
Article
To address the challenge of trichloroethene (TCE) remediation in low permeability zone, an inexpensive Cu-Ni bimetallic cathode was proposed in electrokinetic (EK) remediation system to couple electrokinetic migration with in situ electrochemical hydrodechlorination. Aqueous phase TCE was originally added into the anolyte so that breakthrough curve...
Article
Treatability tests can be carried out to assess the potential effectiveness of thermal treatment technologies under different site conditions and are important for specific technology selection and design. In order to reduce the costs for laboratory tests and expand the insights from previous treatability studies, a one-dimensional (1D) radial fini...
Article
In situ thermal treatment (ISTT) technologies have been applied at sites impacted by non-aqueous phase liquids (NAPLs). There is a need to establish expectations for the treatment of semi-volatile NAPLs, including those consisting primarily of polycyclic aromatic hydrocarbons (PAHs), and the potential benefits and limitations of partial NAPL remova...
Article
Numerical modeling of heat transfer in low porosity fractured rock is challenging because of the complexity associated with the interactions between fractures, bedrock matrix, groundwater, and heat sources. Possible influential parameters include the heat source configuration, the thermal conductivity of the matrix, the velocity of the fluid, the t...
Article
A series of electrical resistance heating (ERH) experiments were performed in a two-dimensional test cell to investigate gas production within clay lenses composed of specified mass fractions of kaolin and #20-30 silica sand (40%, 70% and 100% kaolin by mass). Temperature, electrical, photographic and piezometric data were collected during the heat...
Article
Full-text available
Electrical resistance heating (ERH) experiments were performed in a two-dimensional water-saturated porous medium comprising an electrically conductive, low-permeability clay lens embedded within a less electrically conductive, higher permeability silica sand. These were compared to experiments performed in homogeneous silica sand. All experiments...
Article
A series of intermediate-scale laboratory experiments were completed in a two-dimensional flow cell to investigate gas production and migration during the application of electrical resistance heating (ERH) for the removal of dense non-aqueous phase liquids (DNAPLs). Experiments consisted of heating water in homogeneous silica sand and heating 270 m...
Article
In situ thermal treatment technologies, such as electrical resistance heating and thermal conductive heating, use subsurface temperature measurements in addition to the analysis of soil and groundwater samples to monitor remediation performance. One potential indication of non-aqueous phase liquid (NAPL) removal is an increase in temperature follow...
Chapter
Combining in situ heating with physical recovery, chemical reaction and biodegradation processes has led to a spectrum of in situ thermal remediation options for the cleanup of soils, rock and groundwater impacted by dense nonaqueous phase liquids. The growth in the application and understanding of these technologies over the past two decades has b...
Chapter
Full-text available
Chlorinated solvents are widespread groundwater contaminants whose physical and chemical properties make them difficult to locate and treat within the subsurface. In particular, remediating chlorinated solvent source zones has proven technically challenging, costly and contentious. Nevertheless, there has been a concerted effort over the past 20-25...
Chapter
At a site where groundwater is contaminated by chlorinated solvents, the spatial distribution of contamination and the persistence of the contamination over time is controlled by the interaction between the rate of natural attenuation in groundwater and the rate of natural attenuation of the source. Recent advances make it possible to describe and...
Chapter
Full-text available
In situ bioremediation (ISB) was not initially considered a feasible technology for treating chlorinated solvent source zones, and it still faces some skepticism. However, experience over the last decade demonstrates that it is a viable technology for treating some source zones, although realistic objectives must be set. It is reasonable to expect...
Chapter
Hydraulic displacement is a mass removal technology that involves recovering dense nonaqueous phase liquids (DNAPLs) from either vertical wells or horizontal drains. This chapter focuses primarily on the application of hydraulic displacement at sites impacted by chlorinated solvent DNAPLs, although some discussion of other types of DNAPLs also is i...
Chapter
Remediation of chlorinated solvent source zones remains extraordinarily challenging today and further advances will require the coordinated efforts of experts from a wide range of scientific disciplines including mathematics, chemistry, geology, hydraulics, geochemistry, microbiology and engineering. Research and development has played a vital role...
Chapter
Significant advances have produced source zone remediation modeling tools of real practical value. These advances include improved understanding of the physics and biogeochemistry of DNAPL source zones, more rigorous mathematical descriptions of the relationships between multiphase flow, groundwater flow, contaminant transport, mass transfer and sp...
Chapter
The ability to remediate a chlorinated solvent source zone depends greatly on the adequacy of source zone characterization. In general, chlorinated solvent contaminants can be present as vapor phase, sorbed phase, aqueous phase, and in the form of dense nonaqueous phase liquids (DNAPLs). The applicability of a particular remediation technology depe...
Chapter
Source zone remediation at a site may be undertaken for a number of reasons. The plume response to source remediation is a complex function of many variables, including the fraction of mass remaining in the source compared to the plume, source concentration compared to regulatory limits, ratio of plume decay rates to groundwater velocity, relations...
Article
[1] This paper concerns a new modeling approach to multicomponent NAPL dissolution and transport, based on analytic solutions and Laguerre series. This approach allows virtually any of the numerous existing 1-D analytic transport solutions in the literature to be coupled with arbitrary boundary conditions stemming from nonlinear NAPL dissolution, a...
Book
Remediation of chlorinated solvent source zones is very difficult, at times controversial, and must be based on state-of-the-art knowledge of the behavior of nonaqueous phase liquids in the subsurface, as well as site specific geology, chemistry, biology and hydrogeology. This volume begins with an overview of the current state-of-the-practice that...
Technical Report
Full-text available
The removal of Dense, Non-Aqueous Phase Liquids (DNAPLs) and associated dissolved phase compounds is challenging in fractured rock given permeability, matrix diffusion, and fracture connectivity issues. Modeling, laboratory treatability studies and a pilot scale application at the NAWC Trenton site were all part of this project. The results of mode...
Article
Numerical simulations were conducted to evaluate the efficacy of in situ field scale chemical oxidation (ISCO) (with permanganate) for trichloroethylene (TCE) and tetrachloroethylene (PCE) DNAPL in eight idealized heterogeneous porous media sites. The goal of this work was to study the effects of DNAPL source zone remediation at the site scale util...
Article
Semianalytical transient solutions have been developed to evaluate what level of fractured porous media (e.g., bedrock or clay) matrix cleanup must be achieved in order to achieve compliance of fracture pore water concentrations within a specified time at specified locations of interest. The developed mathematical solutions account for forward and...
Article
Hydraulic displacement is a mass removal technology suitable for stabilization of a dense, nonaqueous phase liquid (DNAPL) source zone, where stabilization is defined as reducing DNAPL saturations and reducing the risk of future pool mobilization. High resolution three-dimensional multiphase flow simulations incorporating a spatially correlated, he...
Technical Report
Full-text available
ESTCP project ER-200424’s main goal was to address this data gap and assist environmental remediation practitioners in evaluating and selecting appropriate remedial technologies (given particular site conditions and performance goals). More importantly, given that the U.S. Department of Defense (DoD) is moving rapidly towards achieving Response Com...
Article
A two-dimensional experiment employing a heterogeneous sand pack incorporating two pools of trichloroethylene (TCE) was performed to assess the efficacy of electrical resistance heating (ERH) under passive venting conditions. Temperature monitoring displayed the existence of a TCE-water co-boiling plateau at 73.4°C, followed by continued heating to...
Article
Full-text available
The effect of matrix diffusion subject to differential sorption on the potential for Aroclor source identification and quantification in a fractured bedrock environment is examined. Due to sorption, transport is seen to occur at greatly different rates for the various congeners, causing rapid changes in polychlorinated biphenyl (PCB) plume composit...
Article
This paper examines the behaviour of dense, nonaqueous phase liquids (DNAPLs) in fractured media, with an emphasis on waste-disposal ponds constructed in fractured clay and rock. Calculations are presented to estimate the height of DNAPL that may accumulate at the base of a disposal pond prior to initial entry into a water-saturated fracture. This...
Article
This paper presents a mathematical analysis and the results of a series of laboratory experiments investigating in situ dissolution of dense, nonaqueous phase liquid (DNAPL) pools from porous media using solubilizing surfactants under upward-flowing conditions. Surfactant flood experiments were conducted in a one-dimensional glass column packed wit...
Article
Numerical modeling was employed to study the performance of thermal conductive heating (TCH) in fractured shale under a variety of hydrogeological conditions. Model results show that groundwater flow in fractures does not significantly affect the minimum treatment zone temperature, except near the beginning of heating or when groundwater influx is...
Article
The influence of source zone concentration reduction on solute plume detachment and recession times in fractured rock was investigated using new semianalytical solutions to transient solute transport in the presence of advection, dispersion, sorption, matrix diffusion, and first-order decay. Novel aspects of these solutions are: (1) the source zone...
Article
Identification of the composition of an upgradient contaminant source using downgradient monitoring well data is a common practice in applied hydrogeology. A common assumption underlying this sort of analysis is that weathering is innocuous enough that chromatographic data can be used to characterize a multicomponent source without any sort of inve...
Article
High resolution numerical simulation was used to evaluate the performance of DNAPL mass removal technologies in spatially correlated random permeablity fields. A number of template sites were created varying according to mean permeability, permeability variance, DNAPL type, and DNAPL release volume. A reactive transport model (RT3D) was coupled wit...
Article
A two-dimensional semi-analytical heat transfer solution is developed and a parameter sensitivity analysis performed to determine the relative importance of rock material properties (density, thermal conductivity and heat capacity) and hydrogeological properties (hydraulic gradient, fracture aperture, fracture spacing) on the ability to heat fractu...
Article
An asymptotic technique is presented for a class of initial-boundary value problems (IBVP) having an arbitrary time-varying boundary condition. This class of IBVP is traditionally solved using the Laplace transform, meaning that governing equation and boundary condition (BC) are solved jointly in Laplace space. This is inconvenient for many applica...
Article
A series of laboratory experiments were conducted to evaluate the relationship between degree of tetrachloroethylene (PCE) mass removal and heating duration, initial dense nonaqueous phase liquid (DNAPL) saturation, and soil grain size. Data were collected to evaluate the impact of postheating sample temperature on PCE concentration and to calculat...
Article
A three-dimensional two-phase flow model is coupled to a non-linear reactive transport model to study the efficacy of potassium permanganate treatment on dense, non-aqueous phase liquid (DNAPL) source removal in porous media. A linear relationship between the soil permeability (k) and concentration of manganese dioxide precipitate ([MnO2(s)]), k =...
Article
A two-dimensional, transient-flow, and transport numerical model was developed to simulate in situ chemical oxidation (ISCO) of trichloroethylene and tetrachloroethylene by potassium permanganate in fractured clay. This computer model incorporates dense, nonaqueous phase liquid dissolution, reactive aquifer material, multispecies matrix diffusion,...
Article
A fixed-volume release of 1,2-DCE, tracked in space and time with a light transmission/image analysis system, provided a data set for the infiltration, redistribution, and immobilisation of a dense non-aqueous phase liquid (DNAPL) in a heterogeneous porous medium. The two-dimensional bench scale flow cell was packed with a spatially correlated, ran...
Article
This note presents a novel method for determining the changing composition of a multi-component NAPL body dissolving into moving groundwater, and the consequent changes in the aqueous phase solute concentrations in the surrounding pore water. A canonical system of coupled non-linear governing equations is derived which is suitable for representatio...
Article
A mathematical solution for solute transport in a three-dimensional porous medium with a patch source under steady-state, uniform ground water flow conditions was developed by Domenico (1987). The solution derivation strategy used an approximate approach to solve the boundary value problem, resulting in a nonexact solution. Variations of the Domeni...
Article
The time required for dense nonaqueous phase liquid (DNAPL) to cease migrating following release to the subsurface is a valuable component of a site conceptual model. This study uses numerical simulation to investigate the migration of six different DNAPLs in sandy aquifers. The most influential parameters governing migration cessation time are the...
Article
Two-dimensional numerical simulations of two-phase (DNAPL-water) flow in spatially correlated random fields demonstrate the influence of nonwetting phase (NWP) relative permeability–saturation (k r,N –S W) relationships correlated to porous media intrinsic per-meability (k). Both the volume of porous media invaded by the NWP and the length of time...
Article
Numerical simulation is used to examine the relative velocities of DNAPL and aqueous phase plumes in sandy aquifers where lateral spreading of DNAPL has occurred at the base of the aquifer. The scenario being modeled is one where a permeable aquifer is underlain by a sloping aquitard, which results in lateral migration of the DNAPL down the slope,...
Article
In this study, similitude and mass storage analyses are performed to determine time scale factors for the scenario of DNAPL flow in single, one-dimensional parallel plate and variable aperture fractures. The obtained time scale factors are compared to the breakthrough times generated by a validated numerical model which is based on the partial diff...
Article
Phase behaviour experiments employing PCB (Aroclor 1242)/alcohol/water systems were conducted with ethanol (EtOH) and n-propanol (nPA). Both exhibited an affinity for the aqueous phase within the entire two-phase region. As much as 88% by volume (88% vol.) EtOH and 80% vol. nPA were necessary to achieve full miscibility of the PCB in the aqueous ph...
Article
Full-text available
An in situ field technique has been developed and implemented to measure non-aqueous phase liquid (NAPL) entry pressure and subsequently estimate mechanical aperture variability in an undisturbed, water-saturated rock fracture. The field experiment also provided the opportunity to measure wetting phase relative permeability at residual non-wetting...
Article
Following a dense, nonaqueous phase liquid (DNAPL) release to the subsurface, little is known about the rate of DNAPL migration and the time required for its eventual immobilization. Numerical simulations can fill this knowledge gap on the condition that the employed models are sufficiently validated; however, to date, validation for transient DNAP...
Article
An emulsion stabilized by colloidal suspensions of finely divided solids is known as a Pickering emulsion. The potential for polychlorinated biphenyls (PCBs) to form Pickering emulsions ex situ when in contact with powdered solids, such as clays and metal oxides, is investigated here. Bentonite, iron oxide and magnesium oxide dispersions proved to...
Article
Full-text available
Predictions of dense non-aqueous phase liquid (DNAPL) releases are sensitive to the nonwetting phase relative permeability-saturation (kr,N-S) constitutive relationships employed in numerical models. In this study, hysteretic kr,N-S curves were measured for a variety of sands, revealing trends in kr,N-S function shapes that were correlated to sand...
Article
Matrix diffusion can attenuate the rate of plume migration in fractured bedrock relative to the rate of ground water flow for both conservative and nonconservative solutes of interest. In a system of parallel, equally spaced constant aperture fractures subject to steady-state ground water flow and an infinite source width, the degree of plume atten...
Article
This talk provides an overview of field studies, laboratory experiments, and numerical modelling that has been conducted in the past 15 years to examine dense, non-aqueous phase liquid migration in heterogeneous porous media. Particular emphasis will be placed on relating what has been learned under controlled conditions (i.e., the laboratory, nume...
Article
This study examined the factors the influence the time required for a release of dense nonaqueous phase liquid (DNAPL) to cease migrating through heterogeneous porous media below the watertable. Using numerical simulation, the temporal and spatial sensitivity of DNAPL migration was evaluated for four DNAPL source characteristics - nonwetting fluid...
Article
Transient and steady-state analytical solutions are derived to investigate solute transport in a fractured porous medium consisting of evenly spaced, parallel discrete fractures. The solutions incorporate a finite width strip source, longitudinal and transverse dispersion in the fractures, source decay, aqueous phase decay, one-dimensional diffusio...
Article
Flow-through column tests were conducted to investigate the performance of iron wall remediation systems for the degradation of aqueous-phase trichloroethylene (TCE). Concentration profiles under steady-state transport conditions were generated by measuring TCE concentrations at sample ports located at various locations along the length of the colu...
Article
The migration of Dense, Non-Aqueous Phase Liquid (DNAPL) and dissolved phase contamination through a fractured heterogeneous porous medium has been investigated through the use of a multiphase compositional model. The sensitivity of the timescales of migration and the distribution of contaminant in the subsurface to the mean permeability, the varia...
Article
A Discrete Fracture Network (DFN) model was created using FracManr to assess what input parameters are most influential in determining the aerial and vertical extent of capture at an existing pump-and-treat system in southwestern Ontario. Two separate three-level factorial designs were conducted; the first evaluated the effect of changing bedding p...
Article
The rate of DNAPL migration through porous media is dependent, in part, on relative permeability constitutive relationships, which describe the saturation and saturation-history dependence of nonwetting phase permeability at the macroscopic scale. Gerhard and Kueper (2003) demonstrate that accurate prediction of DNAPL migration rates requires detai...
Article
This study examines the influence of constitutive models and their parameters on predictions of the spatial and temporal distribution of a finite release of a dense, nonaqueous phase liquid (DNAPL) into a two-dimensional, spatially correlated random permeability field. The base case simulation employed a comprehensive constitutive model that was va...
Article
Large-scale capillary pressure [$\overline {P}c {\(\overline {S}w \)}$] and effective permeability-saturation [knw${\(\overline {S}w \)}$] constitutive relationships for an incompressible, two-phase system have been developed for a two-dimensional, nonorthogonal fracture network utilizing numerical simulation. The simulations account for capillary,...
Article
This study presents a capillary-pressure saturation (PC-S) constitutive model that incorporates the capillary phenomena necessary for simulating the spatial distribution of nonwetting fluid migrating in a saturated porous medium. To develop a model validation data set, a sequence of dense, nonaqueous phase liquid (DNAPL) pools were emplaced, under...
Article
This study presents a relative permeability-saturation (kr-S) constitutive model that incorporates the critical phenomena necessary for simulating the rates of nonwetting fluid infiltration, redistribution, and immobilization in a saturated porous medium. To develop a model validation data set, the migration of a dense, nonaqueous phase liquid (DNA...
Article
Dense, non-aqueous phase liquids such as chlorinated solvents, PCB oils, creosote, and coal tar are common soil and groundwater contaminants at sites throughout the world. Current source zone remediation approaches typically assume that the residual and pooled DNAPL of interest is no longer migrating. The motivation for partial mass removal from a...
Article
This study examines the influence of constitutive models and their parameters on predictions of the spatial and temporal distribution of a finite release of a dense, nonaqueous phase liquid (DNAPL) into a two-dimensional, spatially correlated random permeability field. The base case simulation employed a comprehensive constitutive model that was va...
Article
This study presents a capillary pressure-relative permeability-saturation (Pc-kr-S) constitutive model that incorporates the key characteristics necessary for simulating the infiltration, redistribution, and immobilization of nonwetting fluid in a saturated porous medium. To develop a model validation data set, the migration of a dense, nonaqueous...
Article
The migration of five dense nonaqueous phase liquids (DNAPLs) through a single fracture in a clay aquitard was numerically simulated with the use of a compositional simulator. The effects of fracture aperture, fracture dip, matrix porosity, and matrix organic carbon content on the migration of chlorobenzene, 1,2-dichloroethylene, trichloroethylene,...
Article
This paper examines the migration of DNAPL and the associated aqueous phase plume through clay-sand sequences. Numerical simulations are carried out examining contaminant distribution and migration rates in single fractures, simple layered clay-sand sequences, and spatially-correlated random fields where all low permeability lenses are assigned fra...
Article
A numerical model (Queen's University Multi-Phase Flow Simulator, QUMPFS) was used to assess the rate of trichloroethylene (TCE) dense, non-aqueous phase liquid (DNAPL) migration through fractured clay, with special attention focused on the influence of interbedded sand lenses. The presence of these sand lenses was found to increase the time requir...
Article
Volume reduction and lowering of capillary pressure within a large DNAPL pool are utilized as objectives in the design of a large-scale dual phase recovery system at a chemical manufacturing facility in the United States. By reducing DNAPL pool height through mass removal, capillary pressure is lowered, resulting in a reduced potential for future v...
Article
Perchloroethylene (PCE) was injected into fractured limestone samples (approximately 0.3 m × 0.3 m square) under controlled conditions to assess nonwetting phase fracture retention capacity. Testing was performed using two rock samples containing a single fracture in each, one fractured along a bedding plane and the other fractured along a prominen...
Article
In this laboratory study, perchloroethylene (PCE) was permitted to migrate through a horizontal rough-walled limestone fracture under controlled conditions to assess fracture retention capacity. Retention of immiscible-phase PCE in the absence of an applied wetting-phase hydraulic gradient varied between 11% and 26% of the fracture volume. A portio...
Article
Laboratory experiments demonstrate that in situ recovery of pooled tetrachloroethene (PCE) from porous media may be accomplished more efficiently using multiple-step alcohol floods than with single alcohol floods. To optimize flooding efficiency while maintaining a low risk of downward DNAPL mobilization, a three-step flooding process is developed...
Article
Dense, nonaqueous phase liquids (DNAPLs) are separate phase compounds that commonly contaminate groundwater supplies. Miscible displacement methods using surfactants and alcohols to recover the DNAPLs have been proposed, but concerns have been raised about mobilizing the DNAPLs deeper into previously uncontaminated media. In this paper, the concern...
Article
A non-equilibrium, two-phase, three-component compositional model for the simulation of alcohol flooding has been developed and tested. Inter-phase mass transfer algorithms allow for transfer of all three components at high concentrations and high mass flux rates using a two-film model. The model has been used to simulate alcohol floods where the a...
Article
The equations for a compositional model for simulation of a two-phase, three-component system with inter-phase mass transfer are developed. Emphasis is placed on development of inter-phase mass transfer equations for incorporation of rate-limited inter-phase mass transfer. Due to the nature of the three-component systems considered, a single-film m...
Article
This study examines the effectiveness of various waterflooding strategies to recover pooled dense nonaqueous phase liquid (DNAPL) from the subsurface at an industrial facility. The relative influence of horizontal injection/recovery well configuration, established hydraulic gradient, and fluid properties is investigated for a site characterized by...
Article
The stable DNAPL pool length formed in a rough-walled fracture is a function of the DNAPL density, fracture dip, interfacial tension, fracture aperture, and applied hydraulic gradient. The presented calculation procedure demonstrates that downward groundwater flow will lead to a lower probability of forming DNAPL pools, and shorter equilibrium pool...
Article
Laboratory experiments employing 90% by volume alcohol solutions are used to compare the abilities of ethanol and 1-propanol to remove pooled tetrachloroethene (PCE) from saturated porous media using low upward hydraulic gradients. Equilibrium ternary phase diagrams measured for the systems water/PCE/ethanol and water/PCE/1-propanol indicate that f...
Article
Upward water flow can arrest the downward migration of dense, non aqueous phase liquids (DNAPLS) through rough-walled fractures provided that a sufficient hydraulic gradient exists. An exact analytical solution to predict the arresting gradient demonstrates that there is little difference between the gradient required to arrest DNAPL migration near...
Article
Hydroxypropyl-β-cyclodextrin (HP-β-CD) enhances the solubility of tetrachloroethylene (PCE) in water both in static and in flowing systems. HP-β-CD does not decrease the interfacial tension between PCE and water and, therefore, should not mobilize immiscible-phase PCE in the subsurface. Rates for the reaction of PCE with metallic iron were measured...
Article
Groundwater contamination by dense, non-aqueous phase liquids (DNAPLs) is a common occurrence throughout industrialized areas of North America. At many sites, DNAPL has migrated through overburden deposits and down into fractured bedrock. Unfortunately, very little is known regarding the retention capacity of rock fractures for DNAPL, or the influe...
Article
A one-dimensional numerical model that simulates the surfactant-enhanced solubilization of pooled DNAPL is presented. Two non-equilibrium expressions describing mass transfer are examined. The mass transfer coefficient is based on the wetting phase Darcy flux, with the mass transfer rate coefficient accounting for the variation of interfacial area...
Article
A total of 11 vertical cores spaced 1 m apart along a single transect were extracted from the Borden aquifer at a location 60 m north-northeast from the site studied by Sudicky previously. Examination of these cores shows the upper 1.5–2.0 m of the aquifer to be comprised of relatively unstructured, fine to medium sands, underlain by a 0.1–0.8 m th...
Article
This study examines the influence of source release location, size, and strength on the infiltration rate and degree of lateral spreading of a dense nonwetting liquid infiltrating into an initially wetting liquid saturated, heterogeneous porous medium. It is demonstrated through numerical simulation in 25 realizations of a spatially correlated rand...
Article
Seven hundred seventy liters of a dense nonaqueous phase liquid (DNAPL), tetrachloroethylene (PCE), were released into an isolated volume of a completely saturated natural sandy aquifer. The release was monitored over a period of 984 hours with a variety of geophysical methods including ground penetrating radar, time domain reflectometry, in situ r...

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