Seismic models refined

On January 31st the Electric Power Research Institute (EPRI), the U.S. Department of Energy (DOE), and the U.S. Nuclear Regulatory Commission (NRC) released a new seismic study that will help U.S. nuclear facilities in the central and eastern US reassess seismic hazards. The project gathered and analyzed data, including historical earthquake and geological data for the entire study region from 1568 through 2008, using a peer-reviewed assessment process.
The NRC said the model can be used to calculate the likelihood of various levels of earthquake-caused ground motions. Calculations with the new model are expected to result in a higher likelihood of a given ground motion compared to calculations done using previous models. These calculations, however, are not equivalent to a nuclear power plant’s overall risk.

Plant operators must combine the information from the new model with a plant’s design and safety features to determine site-specific risks. The NRC said the new seismic model will be used by nuclear power plants in the central and eastern United States for these re-evaluations, in addition to being used for licensing of new nuclear facilities.