Manganese sourcing and transport in Massachusetts groundwater: Understanding dissolution mechanisms and creating a temporally variant database

Grant Award Year: 
2020-2021
David Boutt
Justin Richardson
Research Description: 
An estimated 2.6 million people in the US consume groundwater with elevated manganese concentrations. Many New England states have over 20% of groundwater samples with elevated Mn. The USEPA has a secondary maximum contaminant limit of 0.05 mg/L for Mn due to discoloration, but neurotoxicological impacts from Mn in drinking water have been observed in both infants and adults. The proposed project will utilize wells in Amherst, Shutesbury, and Pelham, MA to build a time-series of Mn concentrations in groundwater from unconfined, confined, and fractured bedrock aquifers, as well soil pore waters to attain better resolution on the mechanisms of Mn dissolution. It has been found that an increase in depth to water table corresponds to an increase in Mn concentration. Based on previously recorded water table elevation fluctuations (ranging from 5 to 40 foot changes) at the field site, we expect to see fluctuations in Mn concentrations due to redoximorphic conditions created by seasonal water table elevation changes.