Presenter: Omar F. Zaidan
Faculty Advisor: Jeffery A. Greathouse
Phone number: x-6439
E-mail address: ozaidan@hotmail.com

Oral Presentation

Since the introduction of nuclear chemistry, the question of how to dispose of nuclear waste has always been a pressing one to politicians and environmentalists alike. The Yucca Mountain site in Nevada is now the US government’s first choice as a long-term repository for radioactive nuclear waste. We carried out molecular dynamics simulations using UNIX computers. The system consisted of uranyl (UO2+ ions, the form in which uranium is disposed), water (SPC/E model), and montmorillonite clay (the type of soil present at Yucca Mountain). We studied interactions between the uranyl ion and clay surfaces, and followed the trajectory and behavior of the uranyl ion in this environment. Additionally, we observed (at the molecular level) the water molecules as they formed a solvating shell around the uranyl ion. Our main focus was to analyze uranyl behavior in such an environment, particularly its interaction with the clay. Our results complement published experimental data regarding the proposed orientation of the uranyl ion near the surface. Not only does our approach (computer simulation of molecular-level dynamics) enable us to answer many questions without the need of experimenting with real radioactive samples, it also gives interesting results and raises new questions that propose new theories and better understanding of potential uranium waste in our soil.