The Nuclear Regulatory Commission (NRC) will conduct a special inspection at Cooper Nuclear Station to review the circumstances that contributed to a recent problem with one of the plant’s two service water systems. The plant, operated by the Nebraska Public Power District, is located near Brownville, Nebraska.

Cooper Nuclear Station was operating at full power on December 6, when the licensee was unable to establish water flow through a large pipe that discharges water used to cool some of the plant’s safety-related equipment. A second service water system remained operable.

The licensee subsequently determined that a large build-up of silt from Missouri River flooding had blocked the outlet of the pipe. Upon discovery, the licensee removed the silt.

On December 18, NRC Region IV sent an inspector to the site to gather information in preparation for the inspection that will begin on January 13. Three NRC inspectors will spend approximately one week at the site developing a chronology of the event and evaluating the licensee’s cause analysis and adequacy of corrective actions. An inspection report documenting the team’s findings will be publicly available within 45 days of the end of the inspection.