Environmental Remediation and Water Resources, Nuclear Energy and Waste

Active

Fukushima: JAEA-LBNL Collaboration on Repository Geoscience and Technology Development

DOE-SC-Biological and Environmental Research

fukushima_feature_inline

The Fukushima Daiichi Nuclear Power Plant accident in Japan in March 2011 had a significant impact in Japan and more distant global locations, including California. The long-term impact on local communities neighboring Fukushima may be substantial, due to contamination of watersheds to the west of the Fukushima site, with radioactive cesium being the largest potential contributor to dose. However, there is a lack of understanding and predictive capability for the transport of radioisotopes at the catchment-to-watershed scale. One important aspect of responding efficiently to radiological and nuclear accidents is to understand and predict the long-term transport of radionuclides in the environment and among different environmental “compartments,” such as farmland and forest soils, water bodies including rivers, lakes, and reservoirs, and soil pore water and groundwater systems interacting with each compartment. Predictive studies are needed to evaluate and compare the effectiveness of active and passive remediation options and to better guide decision-making regarding human health and the environment.

In response, LBNL-EESA and the Japan Atomic Energy Agency (JAEA) have collaborated to develop numerical methodologies for understanding and predicting the long-term transport of radionuclides within and among different surface-environmental compartments in Japan. This research also contributes to the R&D activities related to environmental remediation and decommissioning after the Fukushima Nuclear Power Plant Accident, and expands upon the previous (since 2008) collaboration between EESA and JAEA to develop numerical methods for predicting radionuclide migration through rock formations.

Since initiation of this project in June 2014 (focusing on Task A-1, Multiscale Catchment-to-Watershed Modeling), the following key objectives have been addressed:

  • Identification of research direction via discussion and site visit with JAEA in Japan;
  • The acquisition of Ogi Dam data, which will serve for benchmarking purposes;
  • Initial development of an integrated hydrology model for the Ogi Dam site;
  • Topographic processing of a 12.4 m Digital Elevation Model (DEM) and simulation of naturally forming river network at the Ogi Dam site;
  • Construction of heterogeneous subsurface model layers (soils and bedrock) for a benchmark problem on the Ogi Dam site;
  • Model integration of land use and land cover (LULC) data from high-resolution remote-sensing data from the Ogi Dam site;
  • Acquisition of meteorological forcing data at hourly time steps for the Ogi Dam site.

fukushima_feature_inline2Investigators on this project are also developing methods to carry out molecular dynamics (MD) simulations of small illite crystals surrounded by liquid water.  The objective is to characterize the adsorption of cesium on different illite surface sites (basal surfaces, edge surfaces, frayed-edge sites). Accomplishments include the development of force-field parameters for illite edge surfaces, the optimization of the initial distribution of K+ in the collapsed illite interlayers, and a preliminary identification of frayed-edge site precursors in simulations of flexible illite structures.