This Chapman Conference is intended to review a decade of Earth science research on the mechanism(s) of arsenic mobilization in groundwater of southern Asia, identify those areas where a consensus has emerged and, in the case of several important open questions that remain, determine what types of experiments or studies are needed.
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Date:
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24.03.2009 - 27.03.2009 |
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National/International:
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International |
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Language:
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English |
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Type:
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Conference |
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Location:
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Siem Reap, Cambodia |
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Conference web site at:
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Session Topics
Underlying (Bio)Geochemical Processes
- What is the relative timing of release of As and Fe?
- What are the biogeochemical processes responsible for arsenic (and iron) release?
- How important are potential back-reactions – e.g. arsenic adsorption?
- What fuels the biogeochemical process – e.g., plant- vs. animal-derived, or recent vs. ancient, organic matter?
- Are there critical nutrients limiting release of arsenic, and is there a source of these nutrients in arsenic hotspots?
- Can a detailed understanding of microbial populations help with understanding the distribution of As in groundwater?
Role of Hydrogeology and Transport
- How are groundwater arsenic concentrations affected by
surface conditions – e.g. clay or sand soils; agriculture, villages,
ponds or rivers?
- Is arsenic mobilized at a greater rate from certain types of sediments?
- Has the development of paddy fields significantly influenced the pattern of arsenic concentrations in groundwater?
- What will be the consequences of prolonged irrigation of rice paddies with groundwater elevated in arsenic?
Vulnerability of Low-Arsenic Aquifers – Policy Implications
- Is the age of a well since installation relevant and if so, how?
- How
do arsenic concentrations respond to changes in recharge from village
construction, pond construction, shifting agricultural practices?
- Does the release of organic carbon from latrines lead to arsenic enrichments in groundwater?
- How do arsenic concentrations vary with concentrations of other potentially harmful solutes, such as manganese and heavy metals?
- What simple/cheap observations might aid the targeting of low arsenic aquifers?
- Can biogeochemical processes be harnessed to remove arsenic from groundwater in situ and ex situ?
- Do we know enough about the biogeochemistry/microbial ecology of deep wells, and how they will respond to prolonged pumping?
Consensus(?) and Critical Experiments
- What are the similarities and differences between Himalaya
catchments where arsenic is found (or not found) in groundwater in
terms of spatial patterns, organic carbon sources, and land-use
practices?
- Are there commonalities between the mechanisms of arsenic release in inland and coastal aquifers?
- Are laboratory studies to identify arsenic-mobilizing microorganisms and the functional genes that they carry useful?
- Can laboratory experiments help us understand processes in situ and inform mitigation strategies?
- Could
hydrogeologic methods widely applied in the West to groundwater
contamination problems (3D flow and transport modeling, 3D networks of
pressure transducers, field-scale tracer tests...) be applied to
understand arsenic contamination in poor countries?
- Why have these methods been applied so sparingly?
- What should we as a research community do collectively to project future groundwater levels of arsenic and evaluate long-term solutions?
Deadlines | November 21,2008 | Submission of abstracts |
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