This likely won’t come as a surprise to those who closely follow the Pilgrim nuclear power plant, but the NRC will be bumping up its level of oversight for the Plymouth, Mass., reactor.
At the conclusion of every quarter, U.S. nuclear power plant owners voluntarily provide the agency with data that determines if there will be any changes to the Performance Indicators for each facility. The indicators cover areas such as the number of unplanned shutdowns, emergency siren functionality and the effectiveness of radiological controls.
Based on the update of indicator data following the third quarter of 2013, Pilgrim saw its Performance Indicator for Unplanned Scrams (shutdowns) with Complications shift from “green” to “white.” This indicator tracks unplanned scrams that require additional operator actions and that are more risk-significant than uncomplicated shutdowns.
This adjustment resulted in the NRC notifying Entergy, the plant’s owner, that additional scrutiny would be applied to the site. More specifically, the facility moved from Licensee Response Column of the NRC’s Action Matrix – connoting normal oversight – to the Regulatory Response Column – signaling additional inspections by the agency.
Now, with the finalization of 2013 fourth-quarter data, another indicator for Pilgrim has also gone from “green” to “white.” In this case, the Performance Indicator for Unplanned Scrams per 7,000 Hours of Operation is affected. This indicator makes that transition if a plant experiences more than three unplanned shutdowns during that period of time.
This will lead to Pilgrim moving to the Degraded Cornerstone Column of the Action Matrix and result in still more inspections by the NRC. There will also be greater interaction between NRC senior managers and plant management to reach a better understanding of actions taken or planned to address the problems.
Two Performance Indicators related to an increased number of unplanned plant shutdowns over the past year crossed the green/white threshold and shows the company needs to focus greater attention on understanding why this trend is occurring. For the NRC’s part, we need to apply more resources to assess Entergy’s efforts to determine the root causes and to implement corrective actions. The NRC will also conduct its own independent evaluation of the root causes.
In March, the NRC will issue its Annual Assessment Letters for each plant. That letter for Pilgrim will reflect its current status and list inspections the agency will be carrying out in response to the indicator revisions. The letters will be available on the NRC web site.