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• 81. [Article] Analysis and numerical simulation of the ground water system at the Bonneville navigation lock site, Oregon

  As part of the new navigation lock for Bonneville Dam a new water source for the Bonneville Fish Hatchery must be supplied. The hatchery is located on the Oregon side of the Columbia River downstream of ...

  Citation × Citation Citation Abstract Copy Title: Analysis and numerical simulation of the ground water system at the Bonneville navigation lock site, Oregon Author: Baron, Dirk Year: 1990 As part of the new navigation lock for Bonneville Dam a new water source for the Bonneville Fish Hatchery must be supplied. The hatchery is located on the Oregon side of the Columbia River downstream of the dam. It requires large quantities of water free from chemical and biological contamination. In addition, the water has to be in a narrow temperature range. Currently the fish hatchery receives its water from a well field that is located on the alluvial terrace downstream of Bonneville Dam. The well field lies in the proposed approach channel for the new lock and has to be abandoned during construction of the lock. For the continued water supply of the hatchery, a new well field will be developed north of the approach channel. Early in the planning phase for the new lock, concerns were raised about the potential impact of the relocation of the well field and the excavation of the new approach channel on the hatchery. To assess these concerns and to assure a continuous water supply during and after construction, a hydrogeologic investigation was initiated. Within the framework of the investigation this study focuses on the analysis of pumping test data and the development of a three-dimensional ground water flow model for the site. Title: Analysis and numerical simulation of the ground water system at the Bonneville navigation lock site, Oregon Author: Baron, Dirk Year: 1990 As part of the new navigation lock for Bonneville Dam a new water source for the Bonneville Fish Hatchery must be supplied. The hatchery is located on the Oregon side of the Columbia River downstream of the dam. It requires large quantities of water free from chemical and biological contamination. In addition, the water has to be in a narrow temperature range. Currently the fish hatchery receives its water from a well field that is located on the alluvial terrace downstream of Bonneville Dam. The well field lies in the proposed approach channel for the new lock and has to be abandoned during construction of the lock. For the continued water supply of the hatchery, a new well field will be developed north of the approach channel. Early in the planning phase for the new lock, concerns were raised about the potential impact of the relocation of the well field and the excavation of the new approach channel on the hatchery. To assess these concerns and to assure a continuous water supply during and after construction, a hydrogeologic investigation was initiated. Within the framework of the investigation this study focuses on the analysis of pumping test data and the development of a three-dimensional ground water flow model for the site. Close

• 82. [Article] 'Sticky spots' and subglacial lakes under ice streams of the Siple Coast, Antarctica

  Locations of subglacial lakes discovered under fast-moving West Antarctic ice streams tend to be associated with topographic features of the subglacial bed or with areas that have strong variations in ...

  Citation × Citation Citation Abstract Copy Title: 'Sticky spots' and subglacial lakes under ice streams of the Siple Coast, Antarctica Author: Sergienko, Olga V., Hulbe, Christina L. Year: 2011 Locations of subglacial lakes discovered under fast-moving West Antarctic ice streams tend to be associated with topographic features of the subglacial bed or with areas that have strong variations in basal conditions. Inversion of ice-stream surface velocity indicates that basal conditions under ice streams can be highly variable and that there can be widespread regions where basal traction is high. To seek an explanation for why lakes appear to be sited near areas with high basal traction, we use numerical models to simulate ice-stream dynamics, thermodynamics and subglacial water flow. We demonstrate that the ice flow over high basal traction areas produces favourable conditions for the ponding of meltwater. Energy dissipation associated with ice sliding over a region with high basal traction constitutes a water source supplying a lake, and ice-thickness perturbations induced by ice flow over variable traction create local minima in hydraulic potential. Variations in thermodynamic processes caused by such ice flow could be responsible for limiting the horizontal extent of the subglacial lakes. Title: 'Sticky spots' and subglacial lakes under ice streams of the Siple Coast, Antarctica Author: Sergienko, Olga V., Hulbe, Christina L. Year: 2011 Locations of subglacial lakes discovered under fast-moving West Antarctic ice streams tend to be associated with topographic features of the subglacial bed or with areas that have strong variations in basal conditions. Inversion of ice-stream surface velocity indicates that basal conditions under ice streams can be highly variable and that there can be widespread regions where basal traction is high. To seek an explanation for why lakes appear to be sited near areas with high basal traction, we use numerical models to simulate ice-stream dynamics, thermodynamics and subglacial water flow. We demonstrate that the ice flow over high basal traction areas produces favourable conditions for the ponding of meltwater. Energy dissipation associated with ice sliding over a region with high basal traction constitutes a water source supplying a lake, and ice-thickness perturbations induced by ice flow over variable traction create local minima in hydraulic potential. Variations in thermodynamic processes caused by such ice flow could be responsible for limiting the horizontal extent of the subglacial lakes. Close

• 83. [Article] Interactions between microbial dynamics, water flow, and solute transport in unsaturated porous media

  Bioremediation in the vadose zone is unpredictable because of poor understanding of factors influencing microbial growth in this environment. A lab-scale experimental system was developed to examine, noninvasively, interactions ...

  Citation × Citation Citation Abstract Copy Title: Interactions between microbial dynamics, water flow, and solute transport in unsaturated porous media Author: Yarwood, Rockie R. Bioremediation in the vadose zone is unpredictable because of poor understanding of factors influencing microbial growth in this environment. A lab-scale experimental system was developed to examine, noninvasively, interactions between microbial growth, water flow, and solute transport in unsaturated porous media. Measurements of microbial colonization, and its impact on hydrology, were facilitated by using the luxCDABE-containing reporter bacterium Pseudomonas fluorescens HK44 and digital CCD imaging. Experiments were conducted in glass-walled two-dimensional flow cells (45 x 50 x 1 cm) packed with silica sand. Several bioengineering problems associated with chamber design and function required solution before microbial experiments were successful. These included: choice of materials for chamber components; development of sterilization, packing, and inoculation protocols; and development of procedures for data collection and chamber maintenance during experiments lasting several days. Bacterial growth was mapped daily by quantifying development of salicylate-induced bioluminescence. A model relating the rate of increase in light emission after induction successfully predicted microbial densities over four orders of magnitude (R²=0.95) provided that sufficient oxygen for the bioluminescence reaction was available. Total model-predicted growth during a one-week experiment agreed with potential growth calculated from the mass-balance of the system and previously established kinetic parameters (predicted, 1.2x10¹² cells; calculated, 1.7x10¹² cells). Although the rate of expansion of the colonized zone (and predicted populations in newly colonized regions) remained relatively constant, the proportion of the daily potential growth remaining within the chamber declined over time. Monitoring of bioluminescence revealed the development of an (hypothesized) anaerobic zone associated with microbial growth in the unsaturated porous media. Water content and flow streams were measured using light transmission. Accumulation of microbial growth modified the hydrologic properties of the sand causing up to 50% decrease in saturation within the colonized zone, diversion of flow around the colonized zone, and lowering (5 cm) of the capillary fringe height. Apparent solute velocity through the colonized region was reduced from 0.39 cm min⁻¹ (R²=0.99) to 0.25 cm min⁻¹ (R²=0.99). These experiments provide proof-of-concept for combining light transmission and bioluminescence technologies to study interactions between microbial growth and hydrology in unsaturated porous media. Title: Interactions between microbial dynamics, water flow, and solute transport in unsaturated porous media Author: Yarwood, Rockie R. Bioremediation in the vadose zone is unpredictable because of poor understanding of factors influencing microbial growth in this environment. A lab-scale experimental system was developed to examine, noninvasively, interactions between microbial growth, water flow, and solute transport in unsaturated porous media. Measurements of microbial colonization, and its impact on hydrology, were facilitated by using the luxCDABE-containing reporter bacterium Pseudomonas fluorescens HK44 and digital CCD imaging. Experiments were conducted in glass-walled two-dimensional flow cells (45 x 50 x 1 cm) packed with silica sand. Several bioengineering problems associated with chamber design and function required solution before microbial experiments were successful. These included: choice of materials for chamber components; development of sterilization, packing, and inoculation protocols; and development of procedures for data collection and chamber maintenance during experiments lasting several days. Bacterial growth was mapped daily by quantifying development of salicylate-induced bioluminescence. A model relating the rate of increase in light emission after induction successfully predicted microbial densities over four orders of magnitude (R²=0.95) provided that sufficient oxygen for the bioluminescence reaction was available. Total model-predicted growth during a one-week experiment agreed with potential growth calculated from the mass-balance of the system and previously established kinetic parameters (predicted, 1.2x10¹² cells; calculated, 1.7x10¹² cells). Although the rate of expansion of the colonized zone (and predicted populations in newly colonized regions) remained relatively constant, the proportion of the daily potential growth remaining within the chamber declined over time. Monitoring of bioluminescence revealed the development of an (hypothesized) anaerobic zone associated with microbial growth in the unsaturated porous media. Water content and flow streams were measured using light transmission. Accumulation of microbial growth modified the hydrologic properties of the sand causing up to 50% decrease in saturation within the colonized zone, diversion of flow around the colonized zone, and lowering (5 cm) of the capillary fringe height. Apparent solute velocity through the colonized region was reduced from 0.39 cm min⁻¹ (R²=0.99) to 0.25 cm min⁻¹ (R²=0.99). These experiments provide proof-of-concept for combining light transmission and bioluminescence technologies to study interactions between microbial growth and hydrology in unsaturated porous media. Close

• 84. [Image] Minimizing Costs for Water Supply in Rural Areas: The Steady-Flow Water System

  	Citation × Citation Citation Abstract Copy Title: Minimizing Costs for Water Supply in Rural Areas: The Steady-Flow Water System Year: 1997 Title: Minimizing Costs for Water Supply in Rural Areas: The Steady-Flow Water System Year: 1997 Close

• 85. [Article] Documentation for a combined carbon-water flow stand level coniferous forest model

  The following report Introduces a documentation scheme for flow oriented ecosystem models and shows its application to a carbon-water model developed within the coniferous biome. This documentation scheme has ...

  Citation × Citation Citation Abstract Copy Title: Documentation for a combined carbon-water flow stand level coniferous forest model Author: Sollins, P., U.S. International Biological Program. Coniferous Forest Biome, Swartzman, G. L. (Gordon L.), University of Washington The following report Introduces a documentation scheme for flow oriented ecosystem models and shows its application to a carbon-water model developed within the coniferous biome. This documentation scheme has remained operative through revision of this model and expansion of It to include nutrient flows. This model and subsequent versions are operative simulations on the CDC 6400 at the University of Washington using SIMCOMP (Gustafson S Innis (1971)).and give reasonable output. The purpose of this report is mainly to introduce the reader to the documentation scheme which we have found so effective in maintaining a running history of the modeling process for large scale models. We hope that it will lead to the adoption of this or a similar documentation scheme as a standard for ecological modeling. Title: Documentation for a combined carbon-water flow stand level coniferous forest model Author: Sollins, P., U.S. International Biological Program. Coniferous Forest Biome, Swartzman, G. L. (Gordon L.), University of Washington The following report Introduces a documentation scheme for flow oriented ecosystem models and shows its application to a carbon-water model developed within the coniferous biome. This documentation scheme has remained operative through revision of this model and expansion of It to include nutrient flows. This model and subsequent versions are operative simulations on the CDC 6400 at the University of Washington using SIMCOMP (Gustafson S Innis (1971)).and give reasonable output. The purpose of this report is mainly to introduce the reader to the documentation scheme which we have found so effective in maintaining a running history of the modeling process for large scale models. We hope that it will lead to the adoption of this or a similar documentation scheme as a standard for ecological modeling. Close

• 86. [Article] Experimental evaluation and numerical modeling of a water source heat pump evaporator

  Water source heat pumps are increasingly being used for residential and commercial space heating. Typically, these heat pumps are capable of both heating and cooling, and historically the design emphasis has ...

  Citation × Citation Citation Abstract Copy Title: Experimental evaluation and numerical modeling of a water source heat pump evaporator Author: Means, Paul Morency Water source heat pumps are increasingly being used for residential and commercial space heating. Typically, these heat pumps are capable of both heating and cooling, and historically the design emphasis has been on improving the units' cooling performance. Recently, there has been more interest in improving the heating performance, however, in order to optimize the design for improved heating performance data on the heat pump components operating in the heating mode are required. These data have not been available for the waterto- refrigerant heat exchangers typically installed in unitary water source heat pumps. The purpose of this work is to provide performance data on such heat exchangers operating as evaporators (data is available for the heat exchangers operating as condensers) and to provide a numerical model by which a limited amount of evaporator data might be expanded for system modeling and optimization studies. A well instrumented water-to-water heat pump was assembled for the purpose of testing two such water-to-refrigerant heat exchangers to determine their heat transfer and refrigerant pressure drop characteristics as evaporators. The overall heat transfer coefficient for each of the two heat exchangers was found to be a strong function of both the water and refrigerant flow rates and a relatively weak function of the refrigerant evaporation temperature. The refrigerant pressure drop was determined to be highly dependent on the refrigerant flow rate and only slightly dependent on the evaporator temperature. The overall heat transfer coefficient showed an apparent difference between parallel and counter flow conditions. This coefficient, as defined by the log-mean temperature difference, was slightly higher for the counter flow condition. A numerical model of the evaporator was developed and compared with the experimental results. The model follows a numerical solution in which the governing equations (continuity, momentum, and energy) are solved for a finite control volume and an appropriate finitedifference scheme is used to continue the solution step-wise along the length of the heat exchanger. The numerical model accurately predicts the effect of flow rate and temperature on refrigerant pressure drop and the effect of water flow rate and direction on the overall heat transfer coefficient. The model does not accurately predict the effect of evaporator temperature and refrigerant flow rate on the heat transfer coefficient. Title: Experimental evaluation and numerical modeling of a water source heat pump evaporator Author: Means, Paul Morency Water source heat pumps are increasingly being used for residential and commercial space heating. Typically, these heat pumps are capable of both heating and cooling, and historically the design emphasis has been on improving the units' cooling performance. Recently, there has been more interest in improving the heating performance, however, in order to optimize the design for improved heating performance data on the heat pump components operating in the heating mode are required. These data have not been available for the waterto- refrigerant heat exchangers typically installed in unitary water source heat pumps. The purpose of this work is to provide performance data on such heat exchangers operating as evaporators (data is available for the heat exchangers operating as condensers) and to provide a numerical model by which a limited amount of evaporator data might be expanded for system modeling and optimization studies. A well instrumented water-to-water heat pump was assembled for the purpose of testing two such water-to-refrigerant heat exchangers to determine their heat transfer and refrigerant pressure drop characteristics as evaporators. The overall heat transfer coefficient for each of the two heat exchangers was found to be a strong function of both the water and refrigerant flow rates and a relatively weak function of the refrigerant evaporation temperature. The refrigerant pressure drop was determined to be highly dependent on the refrigerant flow rate and only slightly dependent on the evaporator temperature. The overall heat transfer coefficient showed an apparent difference between parallel and counter flow conditions. This coefficient, as defined by the log-mean temperature difference, was slightly higher for the counter flow condition. A numerical model of the evaporator was developed and compared with the experimental results. The model follows a numerical solution in which the governing equations (continuity, momentum, and energy) are solved for a finite control volume and an appropriate finitedifference scheme is used to continue the solution step-wise along the length of the heat exchanger. The numerical model accurately predicts the effect of flow rate and temperature on refrigerant pressure drop and the effect of water flow rate and direction on the overall heat transfer coefficient. The model does not accurately predict the effect of evaporator temperature and refrigerant flow rate on the heat transfer coefficient. Close

• 87. [Article] Pudding River Watershed Assessment, 2006

  Abstract -- Northeast of Salem, five large streams flow west out of the Cascade Mountains to join the Pudding River as it meanders north across the broad Willamette Valley and to its confluence with the ...

  Citation × Citation Citation Abstract Copy Title: Pudding River Watershed Assessment, 2006 Abstract -- Northeast of Salem, five large streams flow west out of the Cascade Mountains to join the Pudding River as it meanders north across the broad Willamette Valley and to its confluence with the Molalla River near Canby. In this document, we characterize past and current watershed conditions and identify opportunities for improving conditions in this watershed. Chapter headings include: introduction and watershed overview, water quality, fish populations and aquatic habitat, water flow and use, riparian vegetation and wetlands, and riparian and stream restoration. The two appendices deal with Pudding River watershed history and BLM Conservation Strategy objectives. 221 pp. Numerous illustrative maps in PDF format accompany this report. Title: Pudding River Watershed Assessment, 2006 Abstract -- Northeast of Salem, five large streams flow west out of the Cascade Mountains to join the Pudding River as it meanders north across the broad Willamette Valley and to its confluence with the Molalla River near Canby. In this document, we characterize past and current watershed conditions and identify opportunities for improving conditions in this watershed. Chapter headings include: introduction and watershed overview, water quality, fish populations and aquatic habitat, water flow and use, riparian vegetation and wetlands, and riparian and stream restoration. The two appendices deal with Pudding River watershed history and BLM Conservation Strategy objectives. 221 pp. Numerous illustrative maps in PDF format accompany this report. Close

• 88. [Article] A numerical model for the fate and transport of chlorinated phenols in groundwater

  The objective of this study was to develop a numerical model for the movement and fate of chlorinated phenols in groundwater. In the first part, a numerical model for several different equilibrium and ...

  Citation × Citation Citation Abstract Copy Title: A numerical model for the fate and transport of chlorinated phenols in groundwater Author: Lee, Sang Bong The objective of this study was to develop a numerical model for the movement and fate of chlorinated phenols in groundwater. In the first part, a numerical model for several different equilibrium and nonequilibrium sorption processes under isothermal conditions is developed for one-dimensional, steady-state water flow in soil columns. The simulated breakthrough curves can be used to estimate sorption parameters from the results of column experiments. The second part presents a one-dimensional numerical model for the fate and transport of chlorinated phenols for one-dimensional, steady-state groundwater flow. The numerical model includes the transport processes of advection, dispersion, sorption, biological degradation, and decay. The set of governing differential equations is solved by Newton-Raphson iteration and the finite difference method. Two different groups of microorganisms are assumed to be involved in the degradation; one group for the reductive dechlorination of the electron acceptor/donor pair and the other group for the fermentation of the electron donor. Inhibition effects due to presence of multiple substrates are included in the Monod kinetics. Simulated breakthrough curves are presented for a range of assumed model parameters and will be compared with measured concentrations in a series of miscible displacement experiments in laboratory columns. Title: A numerical model for the fate and transport of chlorinated phenols in groundwater Author: Lee, Sang Bong The objective of this study was to develop a numerical model for the movement and fate of chlorinated phenols in groundwater. In the first part, a numerical model for several different equilibrium and nonequilibrium sorption processes under isothermal conditions is developed for one-dimensional, steady-state water flow in soil columns. The simulated breakthrough curves can be used to estimate sorption parameters from the results of column experiments. The second part presents a one-dimensional numerical model for the fate and transport of chlorinated phenols for one-dimensional, steady-state groundwater flow. The numerical model includes the transport processes of advection, dispersion, sorption, biological degradation, and decay. The set of governing differential equations is solved by Newton-Raphson iteration and the finite difference method. Two different groups of microorganisms are assumed to be involved in the degradation; one group for the reductive dechlorination of the electron acceptor/donor pair and the other group for the fermentation of the electron donor. Inhibition effects due to presence of multiple substrates are included in the Monod kinetics. Simulated breakthrough curves are presented for a range of assumed model parameters and will be compared with measured concentrations in a series of miscible displacement experiments in laboratory columns. Close

• 89. [Article] Sub-regional detention siting : a methodology using GIS

  The Mt. Scott watershed in northern Clackamas County, Oregon is an urban watershed that lies inside the Portland metropolitan urban growth boundary. Urbanization of the watershed began in the early 1970s ...

  Citation × Citation Citation Abstract Copy Title: Sub-regional detention siting : a methodology using GIS Author: Murdock, Carol L. The Mt. Scott watershed in northern Clackamas County, Oregon is an urban watershed that lies inside the Portland metropolitan urban growth boundary. Urbanization of the watershed began in the early 1970s and has recently accelerated. A landscape level analysis of the urbanization process was combined with the results of a recently completed storm water master plan for the area. The project resulted in the identification of potential locations for combined detention and water quality facilities. It also served to further justify the recent revision of surface water management rules and regulations to include requirements for lower release rates from detention facilities and riparian and wetland buffers. Geographic Information Systems (GIS) was used extensively throughout the project to provide data input into the XPSWMM model that was used to analyze storm water flows and to identify infrastructure needs and requirements. In addition, GIS played a pivotal role in identifying factors which may be contributing to changes in stream condition in the basin. The results of this analysis project will be used by surface water managers in their continuing effort to refine current surface water management rules and regulations in the face of on-going development and continued urbanization. Title: Sub-regional detention siting : a methodology using GIS Author: Murdock, Carol L. The Mt. Scott watershed in northern Clackamas County, Oregon is an urban watershed that lies inside the Portland metropolitan urban growth boundary. Urbanization of the watershed began in the early 1970s and has recently accelerated. A landscape level analysis of the urbanization process was combined with the results of a recently completed storm water master plan for the area. The project resulted in the identification of potential locations for combined detention and water quality facilities. It also served to further justify the recent revision of surface water management rules and regulations to include requirements for lower release rates from detention facilities and riparian and wetland buffers. Geographic Information Systems (GIS) was used extensively throughout the project to provide data input into the XPSWMM model that was used to analyze storm water flows and to identify infrastructure needs and requirements. In addition, GIS played a pivotal role in identifying factors which may be contributing to changes in stream condition in the basin. The results of this analysis project will be used by surface water managers in their continuing effort to refine current surface water management rules and regulations in the face of on-going development and continued urbanization. Close

• 90. [Article] Tillamook Bay comprehensive conservation and mangement plan : restoring the balance

  Citation × Citation Citation Abstract Copy Title: Tillamook Bay comprehensive conservation and mangement plan : restoring the balance Title: Tillamook Bay comprehensive conservation and mangement plan : restoring the balance Close