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Vadose Zone Journal, 2005
Performance evaluation of evapotranspirative (ET) covers is critinicipal solid waste recommended ... more Performance evaluation of evapotranspirative (ET) covers is critinicipal solid waste recommended by the USEPA (Koercal for waste containment. The purpose of this study was to evaluate ner and Daniels, 1997). Resistive barriers rely on low ET covers at sites in Texas and New Mexico representative of arid hydraulic conductivity to minimize water movement into and semiarid regions in the southwestern USA using water balance monitoring during 4-and 5-yr periods and water balance simulations the underlying waste; however, previous studies have using short-term (1-5 yr) and long-term (25 yr) climate forcing. Esti-shown that many resistive covers, particularly compacted mated drainage at the Texas site was related to irrigation while meaclay layers, leak because of desiccation, which can occur sured drainage at the New Mexico site was restricted to the first even in humid settings (Melchior, 1997; Dwyer, 2001; 2 yr of the 5-yr monitoring period. Evapotranspirative covers work Albrecht and Benson, 2001; Albright et al., 2003). Inextremely well in these regions because of the dominance of summer creasing emphasis is being placed on optimal cover deprecipitation (62-80%) that corresponds to periods of highest ET. sign for arid and semiarid regions because they are gen-Strong relationships between decreases in soil water storage and vegeerally considered more suitable for waste disposal than tation productivity at both sites underscore the importance of vegetahumid regions (Reith and Thompson, 1992) and many tion in controlling the water balance in these systems. Simulations of contaminated sites are located in these regions. A varithe Texas site indicate that drainage can occur in response to high preety of alternative cover designs have been proposed for cipitation near the end of the growing season, but such drainage can waste containment in arid and semiarid regions, includbe eliminated with a capillary barrier. Inclusion of a capillary barrier ing monolithic ET covers, capillary barrier ET covers, increased available water storage by a factor of about 2.5 at both and anisotropic barrier ET covers, which all rely on insites. The capillary barrier effect of drainage lysimeters can result in creased water storage rather than low hydraulic conducunderestimation of drainage and overestimation of water storage relativity to minimize water movement into waste (Albright tive to covers not underlain by capillary barriers. The data from this study indicate that a 1-m-thick ET cover underlain by a capillary bar
Boston College International and Comparative Law Review, 1994
Seattle University Law Review, 2008
Civil Engineering Magazine, 2011
Landfill covers that will permanently contain the residuals of chemical warfare agents and pestic... more Landfill covers that will permanently contain the residuals of chemical warfare agents and pesticides at the Rocky Mountain Arsenal Superfund site, in Colorado, were designed to perform many functions, including providing a barrier to water infiltration, soil and wind erosion, and intrusion by wildlife. Designed as alternatives to the types of covers normally used at hazardous waste sites, the covers had to be validated beyond a shadow of a doubt before full-scale construction could begin.
Civil Engineering, 2011
Landfill covers that will permanently contain the residuals of chemical warfare agents and pestic... more Landfill covers that will permanently contain the residuals of chemical warfare agents and pesticides at the Rocky Mountain Arsenal Superfund site, in Colorado, were designed to perform many functions, including providing a barrier to water infiltration, soil and wind erosion, and intrusion by wildlife. Designed as alternatives to the types of covers normally used at hazardous waste sites, the covers had to be validated beyond a shadow of a doubt before full-scale construction could begin.
A large-scale field demonstration comparing final landfill cover designs has been constructed and... more A large-scale field demonstration comparing final landfill cover designs has been constructed and is currently being monitored at Sandia National Laboratories in Albuquerque, New Mexico. Two conventional designs (a RCRA Subtitle 'D' Soil Cover and a RCRA Subtitle 'C' Compacted Clay Cover) were constructed side-by-side with four alternative cover test plots designed for dry environments. The demonstration is intended to evaluate the various cover designs based on their respective water balance performance, ease and reliability of construction, and cost. A portion of this project involves the characterization of vegetation establishment and growth on the landfill covers. The various prototype landfill covers are expected to have varying flux rates (Dwyer et al 2000). The landfill covers are further expected to influence vegetation establishment and growth, which may impact site erosion potential and long-term site integrity. Objectives of this phase are to quantify the types of plants occupying each site, the percentage of ground covered by these plants, the density (number of plants per
Vadose Zone Journal, 2005
Performance evaluation of evapotranspirative (ET) covers is critinicipal solid waste recommended ... more Performance evaluation of evapotranspirative (ET) covers is critinicipal solid waste recommended by the USEPA (Koercal for waste containment. The purpose of this study was to evaluate ner and Daniels, 1997). Resistive barriers rely on low ET covers at sites in Texas and New Mexico representative of arid hydraulic conductivity to minimize water movement into and semiarid regions in the southwestern USA using water balance monitoring during 4-and 5-yr periods and water balance simulations the underlying waste; however, previous studies have using short-term (1-5 yr) and long-term (25 yr) climate forcing. Esti-shown that many resistive covers, particularly compacted mated drainage at the Texas site was related to irrigation while meaclay layers, leak because of desiccation, which can occur sured drainage at the New Mexico site was restricted to the first even in humid settings (Melchior, 1997; Dwyer, 2001; 2 yr of the 5-yr monitoring period. Evapotranspirative covers work Albrecht and Benson, 2001; Albright et al., 2003). Inextremely well in these regions because of the dominance of summer creasing emphasis is being placed on optimal cover deprecipitation (62-80%) that corresponds to periods of highest ET. sign for arid and semiarid regions because they are gen-Strong relationships between decreases in soil water storage and vegeerally considered more suitable for waste disposal than tation productivity at both sites underscore the importance of vegetahumid regions (Reith and Thompson, 1992) and many tion in controlling the water balance in these systems. Simulations of contaminated sites are located in these regions. A varithe Texas site indicate that drainage can occur in response to high preety of alternative cover designs have been proposed for cipitation near the end of the growing season, but such drainage can waste containment in arid and semiarid regions, includbe eliminated with a capillary barrier. Inclusion of a capillary barrier ing monolithic ET covers, capillary barrier ET covers, increased available water storage by a factor of about 2.5 at both and anisotropic barrier ET covers, which all rely on insites. The capillary barrier effect of drainage lysimeters can result in creased water storage rather than low hydraulic conducunderestimation of drainage and overestimation of water storage relativity to minimize water movement into waste (Albright tive to covers not underlain by capillary barriers. The data from this study indicate that a 1-m-thick ET cover underlain by a capillary bar
Boston College International and Comparative Law Review, 1994
Seattle University Law Review, 2008
Civil Engineering Magazine, 2011
Landfill covers that will permanently contain the residuals of chemical warfare agents and pestic... more Landfill covers that will permanently contain the residuals of chemical warfare agents and pesticides at the Rocky Mountain Arsenal Superfund site, in Colorado, were designed to perform many functions, including providing a barrier to water infiltration, soil and wind erosion, and intrusion by wildlife. Designed as alternatives to the types of covers normally used at hazardous waste sites, the covers had to be validated beyond a shadow of a doubt before full-scale construction could begin.
Civil Engineering, 2011
Landfill covers that will permanently contain the residuals of chemical warfare agents and pestic... more Landfill covers that will permanently contain the residuals of chemical warfare agents and pesticides at the Rocky Mountain Arsenal Superfund site, in Colorado, were designed to perform many functions, including providing a barrier to water infiltration, soil and wind erosion, and intrusion by wildlife. Designed as alternatives to the types of covers normally used at hazardous waste sites, the covers had to be validated beyond a shadow of a doubt before full-scale construction could begin.
A large-scale field demonstration comparing final landfill cover designs has been constructed and... more A large-scale field demonstration comparing final landfill cover designs has been constructed and is currently being monitored at Sandia National Laboratories in Albuquerque, New Mexico. Two conventional designs (a RCRA Subtitle 'D' Soil Cover and a RCRA Subtitle 'C' Compacted Clay Cover) were constructed side-by-side with four alternative cover test plots designed for dry environments. The demonstration is intended to evaluate the various cover designs based on their respective water balance performance, ease and reliability of construction, and cost. A portion of this project involves the characterization of vegetation establishment and growth on the landfill covers. The various prototype landfill covers are expected to have varying flux rates (Dwyer et al 2000). The landfill covers are further expected to influence vegetation establishment and growth, which may impact site erosion potential and long-term site integrity. Objectives of this phase are to quantify the types of plants occupying each site, the percentage of ground covered by these plants, the density (number of plants per