Séminaire - Biogeochemical cycling of Radium in the environment - Neha Mehta

IMPMC - Sorbonne Université - 4 place Jussieu, 75005 Paris, tour 23, 4e étage, couloir 22-23, salle 401

Vendredi 12 octobre 2018 à 14 h 30

Neha Mehta - Massachusetts Institute of Technology (MIT), Boston, USA

Abstract

Naturally occurring radionuclide (RN) contamination is widespread in surface andsubsurface environment, resulting in hazardous consequences for the ecosystem. Contamination can originate from anthropogenic activities such as hydraulic fracturing, uranium mining, and nuclear waste disposal or from natural weathering processes. Depending on half-life of RN’s and their environment behavior, they can persist in the environment for varying time periods, requiring elaborate and customized remediation efforts. As such, key to designing such targeted remediation efforts, is to understand geochemical interactions of RN’s within the boundaries of physio-chemical characteristics of the contaminated environment. Here, I will elucidate these interactions for a particular radioactive contaminant, Radium, which is not only a proven health risk, but also an important tracer of various water-rock interactions. In first section of this talk, I will focus on geochemical and physical processes affecting Ra mobility in environments including hydraulic fracturing and shallow groundwater system. In second section of this talk, I will discuss microbial uptake of Ra and elucidate role of biological processes on governing Ra biogeochemical cycling. Overall, these findings will provide improved understanding of environmental behavior of Ra and elucidate novel bioremediation approaches for sites contaminated with Ra.