The Nuclear Regulatory Commission (NRC) staff issued a violation to Prairie Island Nuclear Generating Plant Unit 1 that will result in additional oversight. The two-unit plant operated by Northern States Power Company-Minnesota is located in Welch, Minn., approximately 45 miles southwest of Minneapolis.
NRC inspectors identified the violation during a December 2012 inspection. The violation involved the failure of the plant to maintain an effective emergency plan by not prioritizing the repair of a high range vent gas radiation detector. This detector is used to help determine if an incident should be classified as a General or Site Area Emergency, the two highest of the NRC’s emergency classifications. While this detector was out of service, alternative methods were in place that would allowed plant staff to accurately classify and declare a General or Site Area Emergency.
The utility has repaired the detector, returned it to service and has taken corrective actions to better assess emergency equipment failures.
“Even though the issue did not have an impact on the public, the NRC requires measures be in place and maintained to ensure the health and safety of the public is protected during certain emergency events,” said Region III Administrator Charles Casto. “We have inspected the plant’s corrective actions and know there were alternative means to classify these events, but we will conduct additional inspections to ensure emergency equipment is in working condition.”
The NRC will conduct a supplemental inspection to review whether plant staff understood the cause of the problems, to look at the plant staff’s ability to correctly assess and plan for activities involving emergency preparedness, and to assess their ability to identify and resolve problems with appropriate priority.
The NRC evaluates a nuclear power plant’s performance with a color-coded process that classifies regulatory findings as green, white, yellow or red, in order of increasing safety significance. After considering the information regarding this violation at Prairie Island, the NRC
staff has characterized the inspection finding as white, or as having a low to moderate safety significance.
The company has until April 25 to contest the finding. The NRC inspection letter detailing the final determination will be publically available via the Agencywide Documents Access and Management System on the NRC website using accession number ML13081A503.