Browsing Earth and Environmental Sciences by Title
Now showing items 272-291 of 432
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NAPL Recovery Using CO<sub>2</sub>-Supersaturated Water Injection: Distribution of the CO<sub>2</sub> Gas Phase
(University of Waterloo, 2006)Gas inFusion? is a novel remedial technology that dissolves CO<sub>2</sub> into water under pressure for NAPL recovery. As the supersaturated liquid flows through the porous medium gas evolution occurs in situ as the ... -
Natural Gradient Tracer Tests to Investigate the Fate and Migration of Oil Sands Process-Affected Water in the Wood Creek Sand Channel
(University of Waterloo, 2009-10-02)The In Situ Aquifer Test Facility (ISATF) has been established on Suncor Energy Inc’s (Suncor) oil sands mining lease north of Fort McMurray, Alberta to investigate the fate and transport of oil sands process-affected (PA) ... -
Natural Late Holocene lake level fluctuations recorded in the Ipperwash strandplain, southern Lake Huron
(University of Waterloo, 2017-09-25)The Laurentian Great Lakes (LGL) are the largest system of surface freshwater on Earth. Three factors, glacial isostatic adjustment (GIA), outlet conveyance, and climate processes contribute to natural rises and falls in ... -
Natural source zone depletion of petroleum hydrocarbons under variable temperature and moisture conditions
(University of Waterloo, 2023-02-15)In subsurface environments contaminated by petroleum hydrocarbons (PHCs), the steep geochemical and redox gradients near the water table, the oxygen availability, moisture content, salinity, pH, nutrient concentrations and ... -
New Approaches to the Collection and Interpretation of High Sensitivity Temperature Logs for Detection of Groundwater Flow in Fractured Rock
(University of Waterloo, 2012-08-20)The use of temperature logging for identifying water flow through fractures in sedimentary rock has declined since the 1960’s and 70’s primarily because of low sensor resolution and cross-connected flow along the borehole. ... -
Nickel Isotope Geochemistry in Mine Waste System
(University of Waterloo, 2021-01-13)Metal stable isotope analyses have proven to make valuable contributions to the study of the biogeochemical cycling of metals and metalloids in the environment. Processes that control the release, mobility and fate of ... -
Nitrate sources and cycling at the Turkey Lakes Watershed: A stable isotope approach
(University of Waterloo, 2004)<p class=MsoNormal><span style="mso-spacerun: yes"> </span>Stable isotopic analysis of nitrate (<sup>15</sup>N/<sup>14</sup>N and <sup>18</sup>O/<sup>16</sup>O) was used to trace nitrate sources and cycling under ... -
The Nitrogen Legacy: Understanding Time Lags in Catchment Response as a Function of Hydrologic and Biogeochemical Controls
(University of Waterloo, 2016-09-23)Global population has seen a more than threefold increase over the last 100 years, accompanied by rapid changes in land use and a dramatic intensification of agriculture. Such changes have been driven by a great acceleration ... -
Nitrous oxide and nitrate in the Grand River, Ontario: Sources, production pathways and predictability
(University of Waterloo, 2013-12-13)The increased use of synthetic nitrogen fertilizers since the early 1900s has resulted in greater food production but also problems with nitrogen pollution in freshwaters. Nitrate (NO3-) is a common pollutant in rivers and ... -
Nitrous Oxide Production in the Grand River, Ontario, Canada: New Insights from Stable Isotope Analysis of Dissolved Nitrous Oxide
(University of Waterloo, 2008-10-07)Nitrous oxide (N₂O) is a powerful greenhouse gas, and its atmospheric concentration is increasing dramatically. N₂O is produced through the microbially-mediated processes of nitrification and denitrification. Since these ... -
NO3- and N2O at the Strawberry Creek Catchment: tracing sources and processes using stable isotopes
(University of Waterloo, 2008-08-26)Nitrate (NO3) contamination in agricultural watersheds is a widespread problem that threatens local drinking supplies and downstream ecology. Dual isotopes of NO3- (d15N and d18O) have been successfully used to identify ... -
Numerical investigation of the geophysical response to methane migration in an unconfined aquifer with implications for hydrocarbon wellbore leakage
(University of Waterloo, 2018-05-10)Methane gas leakage from oil and gas development can impact freshwater aquifers. Accurate depictions of gas migration in the subsurface will depend on knowledge of physical parameters and flow system conditions. Geophysical ... -
Numerical Modeling of Financially Sustainable Urban Wastewater Systems
(University of Waterloo, 2016-08-02)A system dynamics model first developed using the software Stella 7.0.2, which explores the complex behavior of the financially sustainable management of water distribution infrastructure, was converted here into a system ... -
Numerical Modeling of Soil Gas Mobility in Shallow Unsaturated Zones
(University of Waterloo, 2021-05-20)In 2016, greenhouse gases (GHG) released from agricultural soils were estimated to be between 19 and 24 megatonnes of carbon dioxide equivalent with an increasing temporal trend. The processes controlling soil gas mobility ... -
Numerical Simulation of Hydrocarbon Fuel Dissolution and Biodegradation in Groundwater
(University of Waterloo, 2000)The behaviour of hydrocarbon fuels in contaminated groundwater systems is studied using a multicomponent reactive transport model. The simulated processes include residual NAPL dissolution, aerobic and anaerobic ... -
Numerical Simulation of Road Salt Impact at the Greenbrook Well Field, Kitchener, Ontario
(University of Waterloo, 2002)Chloride concentrations at the Greenbrook well field in Kitchener, Ontario, have been steadily increasing over the past several decades and may soon pose a threat to drinking water quality. Drinking water limits at some ... -
The Occurrence and Behavior of Rainfall-Triggered Landslides in Coastal British Columbia
(University of Waterloo, 2009-06-19)This thesis seeks to analyze the occurrence and behavior of rainfall-triggered landslides in coastal British Columbia. In particular, it focuses on the analysis of landslide temporal and spatial distributions occurrence ... -
On Modeling Three-Phase Flow in Discretely Fractured Porous Rock
(University of Waterloo, 2013-03-22)Numerical modeling of fluid flow and dissolved species transport in the subsurface is a challenging task, given variability and measurement uncertainty in the physical properties of the rock, the complexities of multi-fluid ... -
ON THE IMPLICATIONS OF VARIOUS APPROACHES TO GROUNDWATER SOURCE PROTECTION
(University of Waterloo, 2008-06-22)Protection of groundwater sources has become an important issue in Canada. Over the last decade many approaches to the protection of groundwater sources have evolved. Some approaches provide qualitative information while ... -
On the sensitivity of modelled groundwater recharge estimates to rain gauge network scale
(Elsevier, 2020-06-01)Rainfall is often the largest component of the water budget and even a small uncertainty percentage may lead to challenges for accurately estimating groundwater recharge as a calculated residual within a water budget ...