Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
Articles 1 - 3 of 3
Full-Text Articles in Physical Sciences and Mathematics
Arsenic Mobilization In An Alluvial Aquifer Of The Terai Region, Nepal, Jasmine Diwakar, Scott Johnston, Edward Burton, Suresh Das Shrestha
Arsenic Mobilization In An Alluvial Aquifer Of The Terai Region, Nepal, Jasmine Diwakar, Scott Johnston, Edward Burton, Suresh Das Shrestha
Associate Professor Edward D Burton
Study Region
A shallow (<50 m) alluvial aquifer in the Terai region of Nepal.
Study Focus
We examine the hydrogeochemical characteristics of a shallow alluvial aquifer system in the Terai region (Nawalparasi district) to identify possible mechanisms and controls on geogenic As mobilization in groundwater. Groundwater and river water samples from a topo-gradient flow-path and floodplain of a minor river draining the Siwalik forehills were analyzed for physico-chemical parameters.
New Hydrological Insights for the Region
The aquifer is characterized by Ca-HCO3 type water and is multi-contaminated, with the WHO guideline values exceeded for As, Mn and F in 80%, 70% and 40% of cases respectively. The middle portion …
50>Liberation Of Acidity And Arsenic From Schwertmannite: Effect Of Fulvic Acid, Chamindra Vithana, Leigh Sullivan, Edward Burton, Richard Bush
Liberation Of Acidity And Arsenic From Schwertmannite: Effect Of Fulvic Acid, Chamindra Vithana, Leigh Sullivan, Edward Burton, Richard Bush
Associate Professor Edward D Burton
Schwertmannite is one of the major components that produces acidity in acid mine drainage (AMD) and acid sulfate soils (ASS) and is also known to be an effective scavenger of Arsenic (As) in such environments. Fulvic acid (FA) is an active component of natural organic matter (NOM) and is known to interact strongly with both schwertmannite and As. Two main environmental hazards related to schwertmannite are acidity liberation and potential re-mobilization of adsorbed or co-precipitated As upon hydrolysis. This study focused on understanding the behaviour of As-substituted schwertmannite with regard to the potential of acidity liberation, the effect of FA …
Arsenic Mobilization And Iron Transformations During Sulfidization Of As(V)-Bearing Jarosite, Scott Johnston, Edward Burton, Annabelle Keene, Britta Planer-Friedrich, Andreas Voegelin, Mark Blackford, Greg Lumpkin
Arsenic Mobilization And Iron Transformations During Sulfidization Of As(V)-Bearing Jarosite, Scott Johnston, Edward Burton, Annabelle Keene, Britta Planer-Friedrich, Andreas Voegelin, Mark Blackford, Greg Lumpkin
Associate Professor Edward D Burton
Jarosite (KFe3(SO4) 2(OH)6) is an important host-phase for As in acid mine drainage (AMD) environments and coastal acid sulfate soils (CASS). In AMD and CASS wetlands, jarosite may encounter S(−II) produced by sulfate reducing bacteria. Here, we examine abiotic sulfidization of As(V)-bearing K-jarosite at pH 4.0, 5.0, 6.5 and 8.0. We quantify the mobilization and speciation of As and identify corresponding Fe mineral transformations. Sulfide-promoted dissolution of jarosite caused release of co-precipitated As and the majority of mobilized As was re-partitioned to a readily exchangeable surface complex (AsEx). In general, maximum As mobilization occurred in the highly sulfidized end-members of …