Optimizing Managed Aquifer Recharge (MAR) Systems for Removal of Trace Organic Chemicals (TOrCs)

Handle URI:
http://hdl.handle.net/10754/322232
Title:
Optimizing Managed Aquifer Recharge (MAR) Systems for Removal of Trace Organic Chemicals (TOrCs)
Authors:
Alidina, Mazahirali
Abstract:
Managed aquifer recharge (MAR) is a low-energy subsurface water treatment system with the potential of being an important component of sustainable water reuse schemes. Alongside common wastewater contaminants, MAR systems have been shown to attenuate a range of trace organic chemicals (TOrCs). Despite several factors being possibly important for TOrC attenuation, many have not been investigated in depth. This research effort investigated three factors affecting attenuation of the moderately degradable TOrCs: primary substrate, adaptation of the microbial community to presence of TOrCs, and groundwater temperature. The overall goal was to optimize TOrC attenuation using different MAR configurations considering how these factors affect TOrC attenuation. The primary substrate composition and concentration significantly impacted attenuation of the moderately degradable TOrCs. Lower primary substrate concentrations and more refractory carbon generally resulted in better TOrC transformation, a more diverse microbial community in the infiltration zone and more diverse capabilities for TOrC degradation. The enzyme group cytochrome P450 may be important for TOrC transformation since its genes were more abundant under carbon-starving primary substrate conditions. Adaptation of the microbial community by pre-exposure to TOrCs was not required in order to degrade them. However, adaptation to the primary substrate was necessary for TOrC biotransformation due to its effect on the microbial community. Attenuation of most TOrCs was unaffected by changes in temperature. Some moderately degradable TOrCs, however, were better attenuated at higher temperatures likely due to increased microbial activity. Others were better degraded at lower temperatures likely due to favorable sorption conditions. In the context of applying MAR systems to potential water reuse schemes within Saudi Arabia, a reconnaissance study of TOrC occurrence in treated wastewater effluents was undertaken. Most of the TOrCs targeted were detected at similar concentrations to US effluents at comparable plants. One of the plants studied, however, displayed a significantly different TOrC footprint from the other treatment plants due to the large number of international visitors in its sewershed. Findings from this occurrence study as well from other tasks provided inputs to a risk assessment framework to compare the effectiveness of MAR systems as part of a multiple-barrier water reuse scheme.
Advisors:
Amy, Gary L.
Committee Member:
Drewes, Jörg E.; Li, Dong; McCabe, Matthew ( 0000-0002-1279-5272 ) ; Missimer, Thomas M.; Peinemann, Klaus-Viktor ( 0000-0003-0309-9598 ) ; Sharp, Jonathan ( 0000-0002-2942-1066 )
KAUST Department:
Biological and Environmental Sciences and Engineering (BESE) Division
Program:
Environmental Science and Engineering
Issue Date:
Jun-2014
Type:
Dissertation
Appears in Collections:
Environmental Science and Engineering Program; Dissertations; Biological and Environmental Sciences and Engineering (BESE) Division

Full metadata record

DC FieldValue Language
dc.contributor.advisorAmy, Gary L.en
dc.contributor.authorAlidina, Mazahiralien
dc.date.accessioned2014-06-25T05:34:55Z-
dc.date.available2014-06-25T05:34:55Z-
dc.date.issued2014-06en
dc.identifier.urihttp://hdl.handle.net/10754/322232en
dc.description.abstractManaged aquifer recharge (MAR) is a low-energy subsurface water treatment system with the potential of being an important component of sustainable water reuse schemes. Alongside common wastewater contaminants, MAR systems have been shown to attenuate a range of trace organic chemicals (TOrCs). Despite several factors being possibly important for TOrC attenuation, many have not been investigated in depth. This research effort investigated three factors affecting attenuation of the moderately degradable TOrCs: primary substrate, adaptation of the microbial community to presence of TOrCs, and groundwater temperature. The overall goal was to optimize TOrC attenuation using different MAR configurations considering how these factors affect TOrC attenuation. The primary substrate composition and concentration significantly impacted attenuation of the moderately degradable TOrCs. Lower primary substrate concentrations and more refractory carbon generally resulted in better TOrC transformation, a more diverse microbial community in the infiltration zone and more diverse capabilities for TOrC degradation. The enzyme group cytochrome P450 may be important for TOrC transformation since its genes were more abundant under carbon-starving primary substrate conditions. Adaptation of the microbial community by pre-exposure to TOrCs was not required in order to degrade them. However, adaptation to the primary substrate was necessary for TOrC biotransformation due to its effect on the microbial community. Attenuation of most TOrCs was unaffected by changes in temperature. Some moderately degradable TOrCs, however, were better attenuated at higher temperatures likely due to increased microbial activity. Others were better degraded at lower temperatures likely due to favorable sorption conditions. In the context of applying MAR systems to potential water reuse schemes within Saudi Arabia, a reconnaissance study of TOrC occurrence in treated wastewater effluents was undertaken. Most of the TOrCs targeted were detected at similar concentrations to US effluents at comparable plants. One of the plants studied, however, displayed a significantly different TOrC footprint from the other treatment plants due to the large number of international visitors in its sewershed. Findings from this occurrence study as well from other tasks provided inputs to a risk assessment framework to compare the effectiveness of MAR systems as part of a multiple-barrier water reuse scheme.en
dc.language.isoenen
dc.subjectManaged Aquifer Rechargeen
dc.subjectTrace Organic Chemicalsen
dc.subjectChemicals of Emerging Concernen
dc.subjectWater Reuseen
dc.subjectSoil Aquifer Treatmenten
dc.subjectLiquid Chromatography tandem mass spectrometryen
dc.titleOptimizing Managed Aquifer Recharge (MAR) Systems for Removal of Trace Organic Chemicals (TOrCs)en
dc.typeDissertationen
dc.contributor.departmentBiological and Environmental Sciences and Engineering (BESE) Divisionen
thesis.degree.grantorKing Abdullah University of Science and Technologyen_GB
dc.contributor.committeememberDrewes, Jörg E.en
dc.contributor.committeememberLi, Dongen
dc.contributor.committeememberMcCabe, Matthewen
dc.contributor.committeememberMissimer, Thomas M.en
dc.contributor.committeememberPeinemann, Klaus-Viktoren
dc.contributor.committeememberSharp, Jonathanen
thesis.degree.disciplineEnvironmental Science and Engineeringen
thesis.degree.nameDoctor of Philosophyen
dc.person.id101871en
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