Hedeff I Essaid, Ph.D. (Former Employee)
Science and Products
Filter Total Items: 38
A functional relation for field-scale nonaqueous phase liquid dissolution developed using a pore network model A functional relation for field-scale nonaqueous phase liquid dissolution developed using a pore network model
A pore network model with cubic chambers and rectangular tubes was used to estimate the nonaqueous phase liquid (NAPL) dissolution rate coefficient, Kdissai, and NAPL/water total specific interfacial area, ai. Kdissai was computed as a function of modified Peclet number(Pe′) for various NAPL saturations (SN) and ai during drainage and imbibition and during dissolution without...
Authors
L.A. Dillard, H.I. Essaid, M.J. Blunt
Progression of natural attenuation processes at a crude oil spill site: II. Controls on spatial distribution of microbial populations Progression of natural attenuation processes at a crude oil spill site: II. Controls on spatial distribution of microbial populations
A multidisciplinary study of a crude-oil contaminated aquifer shows that the distribution of microbial physiologic types is strongly controlled by the aquifer properties and crude oil location. The microbial populations of four physiologic types were analyzed together with permeability, pore-water chemistry, nonaqueous oil content, and extractable sediment iron. Microbial data from three...
Authors
B.A. Bekins, I.M. Cozzarelli, E.M. Godsy, E. Warren, H.I. Essaid, M.E. Tuccillo
Ground water contamination by crude oil near Bemidji, Minnesota Ground water contamination by crude oil near Bemidji, Minnesota
Ground-water contamination by crude oil, and other petroleum-based liquids, is a widespread problem. An average of 83 crude-oil spills occurred per year during 1994-96 in the United States, each spilling about 50,000 barrels of crude oil (U.S. Office of Pipeline Safety, electronic commun., 1997). An understanding of the fate of organic contaminants (such as oil and gasoline) in the...
Authors
G. N. Delin, H.I. Essaid, I.M. Cozzarelli, M.H. Lahvis, B.A. Bekins
Modeling solute-transport and biodegradation with BIOMOC Modeling solute-transport and biodegradation with BIOMOC
No abstract available.
Authors
Hedeff I. Essaid, Barbara A. Bekins
BIOMOC, a multispecies solute-transport model with biodegradation BIOMOC, a multispecies solute-transport model with biodegradation
No abstract available.
Authors
Hedeff I. Essaid, Barbara A. Bekins
Multiphase flow modeling of a crude-oil spill site with a bimodal permeability distribution Multiphase flow modeling of a crude-oil spill site with a bimodal permeability distribution
Fluid saturation, particle-size distribution, and porosity measurements were obtained from 269 core samples collected from six boreholes along a 90-m transect at a subregion of a crude-oil spill site, the north pool, near Bemidji, Minnesota. The oil saturation data, collected 11 years after the spill, showed an irregularly shaped oil body that appeared to be affected by sediment spatial
Authors
Leslie A. Dillard, Hedeff I. Essaid, William N. Herkelrath
Simulation of aerobic and anaerobic biodegradation processes at a crude oil spill site Simulation of aerobic and anaerobic biodegradation processes at a crude oil spill site
A two-dimensional, multispecies reactive solute transport model with sequential aerobic and anaerobic degradation processes was developed and tested. The model was used to study the field-scale solute transport and degradation processes at the Bemidji, Minnesota, crude oil spill site. The simulations included the biodegradation of volatile and nonvolatile fractions of dissolved organic...
Authors
Hedeff I. Essaid, Barbara A. Bekins, E. Michael Godsy, Ean Warren, Mary Jo Baedecker, Isabelle M. Cozzarelli
Field and modeling studies of multiphase fluid flow at the Bemidji, Minnesota crude-oil spill site Field and modeling studies of multiphase fluid flow at the Bemidji, Minnesota crude-oil spill site
No abstract available.
Authors
Hedeff I. Essaid, William N. Herkelrath, L.A. Dillard
Monte Carlo simulations of multiphase flow incorporating spatial variability of hydraulic properties Monte Carlo simulations of multiphase flow incorporating spatial variability of hydraulic properties
To study the effect of spatial variability of sediment hydraulic properties on multiphase flow, oil infiltration into a hypothetical glacial outwash aquifer, followed by oil extraction, was simulated using a cross-sectional multiphase flow model. The analysis was simplified by neglecting capillary hysteresis. The first simulation used a uniform mean permeability and mean retention curve...
Authors
Hedeff I. Essaid, Kathryn M. Hess
Simulation of freshwater and saltwater flow in the coastal aquifer system of the Purisima Formation in the Soquel-Aptos Basin, Santa Cruz County, California Simulation of freshwater and saltwater flow in the coastal aquifer system of the Purisima Formation in the Soquel-Aptos Basin, Santa Cruz County, California
No abstract available.
Authors
H.I. Essaid
Determination of subsurface fluid contents at a crude-oil spill site Determination of subsurface fluid contents at a crude-oil spill site
Measurement of the fluid-content distribution at sites contaminated by immiscible fluids, including crude oil, is needed to better understand the movement of these fluids in the subsurface and to provide data to calibrate and verify numerical models and geophysical methods. A laboratory method was used to quantify the fluid contents of 146 core sections retrieved from boreholes aligned...
Authors
K.M. Hess, W.N. Herkelrath, H.I. Essaid
A multilayered sharp interface model of coupled freshwater and saltwater flow in coastal systems: Model development and application A multilayered sharp interface model of coupled freshwater and saltwater flow in coastal systems: Model development and application
A quasi three-dimensional, finite difference model, that simulates freshwater and saltwater flow separated by a sharp interface, has been developed to study layered coastal aquifer systems. The model allows for regional simulation of coastal groundwater conditions, including the effects of saltwater dynamics on the freshwater system. Vertically integrated freshwater and saltwater flow...
Authors
Hedeff I. Essaid
Science and Products
Filter Total Items: 38
A functional relation for field-scale nonaqueous phase liquid dissolution developed using a pore network model A functional relation for field-scale nonaqueous phase liquid dissolution developed using a pore network model
A pore network model with cubic chambers and rectangular tubes was used to estimate the nonaqueous phase liquid (NAPL) dissolution rate coefficient, Kdissai, and NAPL/water total specific interfacial area, ai. Kdissai was computed as a function of modified Peclet number(Pe′) for various NAPL saturations (SN) and ai during drainage and imbibition and during dissolution without...
Authors
L.A. Dillard, H.I. Essaid, M.J. Blunt
Progression of natural attenuation processes at a crude oil spill site: II. Controls on spatial distribution of microbial populations Progression of natural attenuation processes at a crude oil spill site: II. Controls on spatial distribution of microbial populations
A multidisciplinary study of a crude-oil contaminated aquifer shows that the distribution of microbial physiologic types is strongly controlled by the aquifer properties and crude oil location. The microbial populations of four physiologic types were analyzed together with permeability, pore-water chemistry, nonaqueous oil content, and extractable sediment iron. Microbial data from three...
Authors
B.A. Bekins, I.M. Cozzarelli, E.M. Godsy, E. Warren, H.I. Essaid, M.E. Tuccillo
Ground water contamination by crude oil near Bemidji, Minnesota Ground water contamination by crude oil near Bemidji, Minnesota
Ground-water contamination by crude oil, and other petroleum-based liquids, is a widespread problem. An average of 83 crude-oil spills occurred per year during 1994-96 in the United States, each spilling about 50,000 barrels of crude oil (U.S. Office of Pipeline Safety, electronic commun., 1997). An understanding of the fate of organic contaminants (such as oil and gasoline) in the...
Authors
G. N. Delin, H.I. Essaid, I.M. Cozzarelli, M.H. Lahvis, B.A. Bekins
Modeling solute-transport and biodegradation with BIOMOC Modeling solute-transport and biodegradation with BIOMOC
No abstract available.
Authors
Hedeff I. Essaid, Barbara A. Bekins
BIOMOC, a multispecies solute-transport model with biodegradation BIOMOC, a multispecies solute-transport model with biodegradation
No abstract available.
Authors
Hedeff I. Essaid, Barbara A. Bekins
Multiphase flow modeling of a crude-oil spill site with a bimodal permeability distribution Multiphase flow modeling of a crude-oil spill site with a bimodal permeability distribution
Fluid saturation, particle-size distribution, and porosity measurements were obtained from 269 core samples collected from six boreholes along a 90-m transect at a subregion of a crude-oil spill site, the north pool, near Bemidji, Minnesota. The oil saturation data, collected 11 years after the spill, showed an irregularly shaped oil body that appeared to be affected by sediment spatial
Authors
Leslie A. Dillard, Hedeff I. Essaid, William N. Herkelrath
Simulation of aerobic and anaerobic biodegradation processes at a crude oil spill site Simulation of aerobic and anaerobic biodegradation processes at a crude oil spill site
A two-dimensional, multispecies reactive solute transport model with sequential aerobic and anaerobic degradation processes was developed and tested. The model was used to study the field-scale solute transport and degradation processes at the Bemidji, Minnesota, crude oil spill site. The simulations included the biodegradation of volatile and nonvolatile fractions of dissolved organic...
Authors
Hedeff I. Essaid, Barbara A. Bekins, E. Michael Godsy, Ean Warren, Mary Jo Baedecker, Isabelle M. Cozzarelli
Field and modeling studies of multiphase fluid flow at the Bemidji, Minnesota crude-oil spill site Field and modeling studies of multiphase fluid flow at the Bemidji, Minnesota crude-oil spill site
No abstract available.
Authors
Hedeff I. Essaid, William N. Herkelrath, L.A. Dillard
Monte Carlo simulations of multiphase flow incorporating spatial variability of hydraulic properties Monte Carlo simulations of multiphase flow incorporating spatial variability of hydraulic properties
To study the effect of spatial variability of sediment hydraulic properties on multiphase flow, oil infiltration into a hypothetical glacial outwash aquifer, followed by oil extraction, was simulated using a cross-sectional multiphase flow model. The analysis was simplified by neglecting capillary hysteresis. The first simulation used a uniform mean permeability and mean retention curve...
Authors
Hedeff I. Essaid, Kathryn M. Hess
Simulation of freshwater and saltwater flow in the coastal aquifer system of the Purisima Formation in the Soquel-Aptos Basin, Santa Cruz County, California Simulation of freshwater and saltwater flow in the coastal aquifer system of the Purisima Formation in the Soquel-Aptos Basin, Santa Cruz County, California
No abstract available.
Authors
H.I. Essaid
Determination of subsurface fluid contents at a crude-oil spill site Determination of subsurface fluid contents at a crude-oil spill site
Measurement of the fluid-content distribution at sites contaminated by immiscible fluids, including crude oil, is needed to better understand the movement of these fluids in the subsurface and to provide data to calibrate and verify numerical models and geophysical methods. A laboratory method was used to quantify the fluid contents of 146 core sections retrieved from boreholes aligned...
Authors
K.M. Hess, W.N. Herkelrath, H.I. Essaid
A multilayered sharp interface model of coupled freshwater and saltwater flow in coastal systems: Model development and application A multilayered sharp interface model of coupled freshwater and saltwater flow in coastal systems: Model development and application
A quasi three-dimensional, finite difference model, that simulates freshwater and saltwater flow separated by a sharp interface, has been developed to study layered coastal aquifer systems. The model allows for regional simulation of coastal groundwater conditions, including the effects of saltwater dynamics on the freshwater system. Vertically integrated freshwater and saltwater flow...
Authors
Hedeff I. Essaid