Grantee Research Project Results
Actinides and Heavy Metals in the Environment - The Formation, Stability and Impact of Nano- and Micro-Particles
Jeremy B. Fein*, Peter C. Burns, Patricia A. Maurice
Civil Engineering and Geological Sciences, University of Notre Dame.
* Principal Investigator. Contact Info: 574-631-6101; firstname.lastname@example.org
Quantitative models of subsurface contaminant transport are doomed to failure if the models neglect to account for all major vectors of transport. Presently, most transport models consider only two possible chemical fates for a contaminant: either mobile as a dissolved species, or immobile due to adsorption or precipitation onto the solid geologic matrix. However, groundwater aquifers also contain nano- and micro-particles that are composed of mineral, organic, and microbiological solid phases. These particles can be mobile in the subsurface, and therefore they can markedly enhance contaminant transport. The effects of nano- and micro-particles on contaminant mobilities are poorly understood, and improving our understanding of these processes represents one of the largest challenges currently facing environmental scientists. A quantitative understanding of the chemical controls on particle-contaminant interactions requires an integration of traditional macroscopic and microscopic techniques with state-of-the-art molecular-scale approaches.
The Environmental Molecular Science Institute at University of Notre Dame consists of an interdisciplinary team of environmental scientists whose goal is to improve our understanding of the molecular-scale chemical processes that influence nano- and micro-particle transport. Due to their extreme toxicity and their widespread use in industry and in weapons and nuclear energy production, the actinide elements and heavy metals are of particular concern as groundwater contaminants. We are concentrating on U, Np, Pb, Cu, and Cd, and our primary focus is on the molecular scale chemical processes that control transport of these elements, particularly adsorption, precipitation, and redox reactions. Institute research involves a range of approaches and facilities, including bulk adsorption and solubility measurements, potentiometric titrations, x-ray diffractometry, infrared spectroscopy, electrophoretic mobility measurements, inductively coupled plasma mass spectrometry, DNA microbiological analyses, molecular weight analysis of organic matter, atomic force microscopy, and hydrologic column experiments (University of Notre Dame); x-ray absorption spectroscopy (Advanced Photon Source, Argonne National Lab); and molecular dynamics and ab initio modeling (Sandia National Labs).