Pathways for Contamination
The team also used isotope geochemistry to separate geogenic contaminants that are naturally occurring in the aquifer rocks, such as uranium and fluoride, and those that stem from human-made pollution, such as the high nitrate concentrations that come from untreated sewage and fertilizers leaking into shallow groundwater systems.
“Establishing the pathways of contamination for the various compounds is important for water treatment strategies,” says Richard Wanty, a geochemist with the U.S. Geological Survey in Lakewood, Colo., who was not involved in the new study.
“Natural contamination can be treated at point of use, but it’s generally not possible to fix something like uranium contamination at the source—it’s too pervasive,” he says.
Anthropogenic pollution, on the other hand, can be treated at the source. One such example might be stopping a wastewater plume from getting into groundwater supplies.
More of these kinds of geochemical studies will be needed for India to make progress in providing adequate sanitation and safe drinking water for its growing population of 1.3 billion people, Wanty says.
The study’s methods for vetting groundwater can be applied anywhere in the world that people rely on groundwater, he says.
“This is a very detailed study of a specific geographic area, but one could easily take the geochemical protocols and apply them to other parts of the world, both developed and underdeveloped,” Wanty says. “I hope people don’t refrain from reading this study because it says Rajasthan, India, in the title. This approach can be used anywhere people are using groundwater for drinking water.”
Citation: Morton, M. C. (2019), Widespread contamination found in northwest India’s groundwater, Eos, 100, https://doi.org/10.1029/2019EO130161. Published on 05 August 2019.
*Original article online at https://eos.org/articles/widespread-contamination-found-in-northwest-indias-groundwater