No description available.

Graduation date: 1996

No description available.

Monitored natural attenuation is a cost-effective remediation strategy for the risk reduction of chemicals of concern (CoCs) in contaminated land and waters. This study considers three genuine sites in Germany, undergoing remediation. The objective was to measure a suite of physicochemical and biological parameters, and characterise the sites based on these data. The sites differed by their prevalent type of CoC, with one site impacted by polycyclic aromatic hydrocarbons (PAH), and two sites, situated in Hilden, impacted by BTEX. Sampling of microorganisms was performed using the industrial partner's newly developed matrix. This matrix was used for measurements of microbial respiration rate, ATP content, and 14C mineralisation rate, while groundwater samples were used for microbial luminescent biosensor assays (applying Escherichia coli HB101 pUCD607, Pseudomonas putida F1 Tn5, and Pseudomonas putida F1 TVA8), and for the chemical analysis of CoC, nitrate, iron, manganese, sulphate, and phosphate concentration. Microbial biosensors and respiration tests performed well in the identification of BTEX impacted wells at the Hilden sites, while the results for ATP content and 14C mineralisation were more ambiguous. Factor analysis showed a high impact of sulphate concentration. However, several strong correlations existed between measured parameters, so no single driving force, but a set of environmental influencing factors could be identified at the sites. The remediation progress could be demonstrated by the changes in cluster analyses between two time points. Sulphate and redox potential, the most influential parameters of the Hilden physico-chemical data set, were highlighted and confirmed by multiple linear regression, using a calculated attenuation rate as the dependent variable. Based on this outcome, a reduced sampling regime was proposed. This approach has the potential to reduce sampling costs and time at hydrocarbon contaminated sites, and has adequately demonstrated the use of statistical methods in assessing the remediation progress at a site.

Thesis (M.S.)--Youngstown State University, 2008. / Includes bibliographical references (leaves 120-126). Also available via the World Wide Web in PDF format.

Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 317-342).

Thesis (Ph. D.)--Civil & Environmental Engineering, Georgia Institute of Technology, 2006. / Pennell, Kurt, Committee Chair ; Lawrence Bottomley, Committee Member ; James Mulholland, Committee Member ; Carolyn Ruppel, Committee Member ; D. Webster, Committee Member. Includes bibliographical references.

Thesis (M.Eng.)--Memorial University of Newfoundland, 2004. / Bibliography: leaves 114-118.

Thesis (M.A.)--University of Central Florida, 2008. / Adviser: Brent Marshall. Includes bibliographical references (p.60-69).

Thesis (M.S.)--Michigan State University. Dept. of Resource Development, 2008. / Title from PDF t.p. (viewed on July 27, 2009) Includes bibliographical references (p. 105-106). Also issued in print.