Superfund Research Program
Developing In Situ, Real-time Sensors for Toxicants at Superfund Sites, to Protect Public Health and Optimize Cleanup
- Project Summary
Project Summary (2017-2022)
The Superfund program is responsible for protecting public health and the environment by cleaning up the nation's most contaminated land as well as responding to environmental emergencies. Sediments and soils are commonly the dominant reservoirs of toxicants at Superfund sites, but human exposure to toxicants is not only direct; it can occur via food chains, or, commonly, via water as toxicants are gradually released from soils and aquatic sediments. This project, as part of the Massachusetts Institute of Technology Superfund Research Program (MIT SRP) Center, focuses on two important toxicants, N-nitrosodimethylamine (NDMA) and polycyclic aromatic hydrocarbons (PAHs), but also provides insights and methodologies relevant to the general problem of detection, mapping, and movement of harmful species.
To protect human health and design effective and cost-effective cleanup requires understanding what toxicants are present, how they are distributed, and by what routes they move through the environment and enter people. Gaining this understanding is usually a slow, difficult, and costly process, given the extent and spatial variability of toxicant distributions and the high cost and slow speed of chemical sampling and lab analysis. There is thus a great opportunity to improve remediation protectiveness, effectiveness, and cost efficiency by developing new and cost-effective in situ sensor technologies that can rapidly measure both toxicant concentrations in water and their exchange rates with contaminated sediments. These novel sensors promise to enable research with the potential to give rise to paradigm shifting understanding of the spatiotemporal dynamics of contaminants.
As part of this project, MIT SRP researchers develop and test in situ sensors to measure the concentrations of toxicants in water. The sensors serve as portable sensors by field personnel, as moored long-term sentinel sensors at fixed locations, and for toxicant mapping from operated or autonomous vehicles. Further reflecting the critical role of contaminated sediments, the research team is developing in situ technology to expeditiously determine location-specific rates at which sediment-borne toxicants are released to their surface waters (i.e., benthic fluxes). This information will help improve estimates of human exposure and optimize remediation strategies.
Community interaction is supported by field-testing of new sensors in the Mystic River Watershed, including the tributary Malden River, a water body that is currently facing severe scrutiny for its extensive sediment contamination and for its central role in environmental justice issues in Malden and Everett, MA. This project also creates training opportunities for students to design and test novel sensors, deploy sensors in real-world settings, and take part in community environmental affairs.