Superfund Research Program
Mitigation of As Mobilization in Groundwater
Project Leader: Alexander F. van Geen
Grant Number: P42ES010349
Funding Period: 2000-2021
Project Summary (2006-2011)
This project is intended to augment our fundamental understanding of arsenic (As) behavior in ways that lead directly to a reduction in human exposure in both the U.S. and in Bangladesh. At the Vineland Chemical Superfund site in New Jersey, heavily contaminated with both inorganic As (InAs) and organic As (OrgAs), research focuses on reducing off-site transport of these contaminants in two ways. The effort is directed at polishing effluent from the existing treatment plant using a treatment column containing zero-valent iron (Fe(0)) filings which, this project's previous research has demonstrated, is capable of removing both InAs and OrgAs. Second, the feasibility of reducing off-site transport of As is being explored by installing and monitoring a permeable-reactive barrier containing Fe(0) filings. In Bangladesh, project investigators are ethically compelled to lower the As exposure of study participants. This project focuses on the sustainability of continued withdrawals from those aquifers that are currently low in As. The justification is that these aquifers are currently the only realistic alternative for the ~50 million inhabitants of the country who have been drinking well water with an As content that often exceeds the WHO guideline of 10 ug/L by one to two orders of magnitude. Through detailed monitoring and targeted manipulations in the field and in the laboratory, the combination of hydrological, geochemical, and microbial processes that maintain As concentrations at low levels in both very shallow (<10 m) and deep (>30-150 m) aquifers is being investigated. In a direct application of the approach to mitigation previously developed in this project, the exposure to As and Mn of children and adults, participating in other projects and residing in 25 villages, is being rapidly reduced by targeting safe aquifers for the installation of community wells. The timing of these interventions is closely synchronized with parallel studies of their health impact, conducted under biomedical components of this application.