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Full-Text Articles in Water Resource Management
Anaerobic Biodegradation Of Rdx And Tce: Single- And Dual-Contaminant Batch Tests, Travis S. M. Young, Matthew C. Morley, Daniel D. Snow
Anaerobic Biodegradation Of Rdx And Tce: Single- And Dual-Contaminant Batch Tests, Travis S. M. Young, Matthew C. Morley, Daniel D. Snow
Daniel D Snow
Several sites in the United States have groundwater contaminated with mixtures of high explosives and chlorinated solvents. This research examined the ability of two microbial cultures (anaerobic sludge and a facultative enrichment culture) to biodegrade single- and dual-contaminant mixtures of trichloroethene (TCE) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) under anaerobic conditions. In single component batch tests, both cultures degraded 0.6–1 mg RDX/L and its nitroso metabolites to below detection limits in <7 days. During initial 9-day TCE biodegradation tests, the anaerobic sludge did not transform TCE, whereas the facultative culture transformed approximately 10% of the initial 1.4 mg TCE/L. Prior to dual-contaminant batch …
Emerging Chemicals And Analytical Methods (2005), Matthew C. Morley, Daniel D. Snow, Vince Kuppig
Emerging Chemicals And Analytical Methods (2005), Matthew C. Morley, Daniel D. Snow, Vince Kuppig
Daniel D Snow
Emerging contaminants in the water environment continues to be a strong research focus, as evidenced by the abundance of material published during 2004. This review summarizes peer-reviewed literature pertinent to the field of environmental engineering and science and related to analysis, occurrence, and fate of emerging chemical contaminants in the water environment, focusing on the following broad categories of emerging organic contaminants: antibiotics and pharmaceuticals; personal care products ingredients (PCPIs), endocrine disrupting compounds (EDCs), halogenated compounds (particularly brominated and fluorinated compounds), and disinfection byproducts (DBPs). To maintain this focus, articles pertaining specifically to human and ecological toxicity, bioconcentration or bioaccumulation, …
Detection, Occurrence, And Fate Of Emerging Contaminants In Agricultural Environments (2009), Daniel D. Snow, Shannon L. Bartelt-Hunt, Shannon Devivo, Samuel Saunders, David A. Cassada
Detection, Occurrence, And Fate Of Emerging Contaminants In Agricultural Environments (2009), Daniel D. Snow, Shannon L. Bartelt-Hunt, Shannon Devivo, Samuel Saunders, David A. Cassada
Daniel D Snow
Frequently studied environmental contaminants in agricultural systems include nutrients, sediments, and pesticides. These groups of contaminants typically occur at easily measured concentrations in surface run-off in agricultural watersheds. Nutrients, especially nitrogen, and pesticides have also been shown to impact ground water quality in areas susceptible to contamination. Less well-known are environmental impacts of newer classes of contaminants such as pharmaceuticals, steroids, antibiotic-resistance genes and prion proteins. These “emerging” contaminants clearly have potential to enter the environment and cause known or suspected adverse ecological or human health effects. Release of these contaminants to the environment often has occurred for quite some …
Herbicide Loading To Shallow Ground Water Beneath Nebraska’S Management Systems Evaluation Area, Roy F. Spalding, Darrell G. Watts, Daniel D. Snow, David A. Cassada, Mary E. Exner, James S. Schepers
Herbicide Loading To Shallow Ground Water Beneath Nebraska’S Management Systems Evaluation Area, Roy F. Spalding, Darrell G. Watts, Daniel D. Snow, David A. Cassada, Mary E. Exner, James S. Schepers
Daniel D Snow
Better management practices can counter deterioration of ground water quality. From 1991 through 1996 the influence of improved irrigation practices on ground water pesticide contamination was assessed at the Nebraska Management SystemsEvaluation Area. Three 13.4-ha corn (Zea mays L.) fields were studied: a conventional furrow-irrigated field, a surge-irrigated field and a center pivot–irrigated field, and a center pivot–irrigated alfalfa (Medicago sativa L.) field. The corn fields received one identical banded application of Bicep (atrazine [6-chloro-N-ethyl-N’-(1-methylethyl)-1,3,5-triazine-2,4,-diamine] _ metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl) acetamide]) annually; the alfalfa field was untreated. Ground water samples were collected three times annually from 16 depths of 31 multi-level samplers. …
Detection, Occurrence And Fate Of Emerging Contaminants In Agricultural Environments (2008), Daniel D. Snow, Shannon L. Bartelt-Hunt, Samuel E. Saunders, Shannon L. Devivo, David A. Cassada
Detection, Occurrence And Fate Of Emerging Contaminants In Agricultural Environments (2008), Daniel D. Snow, Shannon L. Bartelt-Hunt, Samuel E. Saunders, Shannon L. Devivo, David A. Cassada
Daniel D Snow
Agricultural settings are affected by a unique set of environmental contaminants typically associated with land use. Nutrients and sediments from run-off and erosion have historically been, and continue to be, studied and understood with respect to their impacts to aquatic environments. Studies involving newer classes of contaminants, such as pharmaceuticals and steroids, are becoming more prevalent as methods for measuring these compounds become available. These “emerging” contaminants clearly have potential to enter the environment and cause known or suspected adverse ecological or human health effects. Release of these contaminants to the environment has occurred for quite some time, but methods …
The Occurrence Of Illicit And Therapeutic Pharmaceuticals In Wastewater Effluent And Surface Waters In Nebraska, Shannon L. Bartelt-Hunt, Daniel D. Snow, Teyona Damon, Johnette Shockley, Kyle Hoagland
The Occurrence Of Illicit And Therapeutic Pharmaceuticals In Wastewater Effluent And Surface Waters In Nebraska, Shannon L. Bartelt-Hunt, Daniel D. Snow, Teyona Damon, Johnette Shockley, Kyle Hoagland
Daniel D Snow
Passive samplers were used to develop semi-quantitative estimates of pharmaceutical concentrations in receiving waters influenced by wastewater effluent. The occurrence and estimated concentration of twenty illicit and therapeutic pharmaceuticals and metabolites in surface waters influenced by wastewater treatment plant (WWTP) discharge and in wastewater effluents in Nebraska were determined using Polar Organic Chemical Integrative Samplers (POCIS). Samplers were installed in rivers upstream and downstream of treated WWTP discharge at four sites and in a discharge canal at a fifth location. Based on differences in estimated concentrations determined from pharmaceuticals recovered from POCIS, WWTP effluent was found to be a significant …