"Groundwater contaminated with naturally occurring arsenic is a widespread problem affecting many alluvial and deltaic aquifer systems throughout the world. The human health toll from consuming groundwater with high levels of arsenic is staggering in its proportions. Furthermore, the use of arsenic contaminated groundwater for irrigation is observed to result in diminished crop yields and thus poses a threat to food security in arsenic affected regions. Decades of research at individual field sites have resulted in the collection of many geochemical and geologic datasets." This photograph was taken during the summer 2014 working group Characterizing global variability in groundwater arsenic at the John Wesley Powell Center for Science Analysis and Synthesis. The working group has yielded multiple publications and is returning to the Powell Center in 2021.