The Department of Chemistry invites you to its departmental seminar today at 4:10 p.m. in Fulmer Hall, room 201.
Dr. Annie Kersting from the Glenn T. Seaborg Institute at Lawrence Livermore National Lab will present, Biogeochemical Controls on Transport of Plutonium in the Environment.
Abstract: Significant releases of plutonium (Pu) into the environment have resulted from nuclear weapons production and the nuclear fuel cycle. A major scientific challenge is to reliably predict and control the cycling and mobility of Pu that has been deposited into the environment. Although substantial progress has been made, the coupled biological, chemical, and physical processes that control this transport are not well understood.
In the last 15-20 years, it has been generally thought that due to its low solubility and high sorption affinity, Pu migration in the environment will be dominated by transport on particulate matter (i.e., colloidal particles). However, recent work performed by our group and others suggests that colloid-facilitated Pu transport may not be the only mechanism by which Pu is transported in the subsurface. In this presentation, I will discuss our recent work that explores several additional biogeochemical mechanisms that may control Pu migration.
We posit that the biogeochemical processes that ultimately control plutonium subsurface mobility/immobility are driven by the local hydrogeologic and geochemical conditions, in concert with the chemical characteristics of the initial actinide source. This has led to Pu transport as intrinsic colloids, pseudocolloids, and aqueous organic complexes. The temporal and spatial limits to Pu migration are controlled by the stability of each of these forms of Pu in groundwater.
