US regulator issues annual plant assessments

08 March 2019

All of the USA's 98 operating commercial reactors were in the US Nuclear Regulatory Commission's (NRC's) two highest performance categories for 2018. Entergy's Pilgrim plant, which had been under enhanced regulatory oversight, has returned to the highest operating level.

Pilgrim (Image: Entergy)

Ninety-three reactors fully met all safety and security performance objectives and were inspected by the NRC using its normal 'baseline' inspection programme. Four reactors - Grand Gulf, Peach Bottom units 2 and 3, and Watts Bar 2 - were assessed as needing to resolve one or two items of low safety significance, requiring additional inspection and follow-up of corrective actions. Watts Bar 2 has resolved its issues since the reporting period ended and has transitioned to the highest performing level, the NRC said.

There were no reactors in the third category of a degraded level of performance. Entergy's Pilgrim plant, which had been the sole reactor in the fourth category - for multiple or repetitive degraded performance - has now moved back to the first category, the NRC said.

Pilgrim, a single-unit 680 MWe boiling water reactor, had been under increased oversight since September 2015, when the NRC finalised a so-called 'white' inspection finding of low-to-moderate safety significance from issues involving the plant's safety relief valves. This, in combination with two earlier 'white' findings, prompted the NRC to move the Massachusetts plant to column 4 of its oversight action matrix.

Following the completion of phased inspections, the NRC in August 2017 issued a Confirmatory Action Letter outlining actions that Entergy must complete to address these issues. That letter has now been closed, Entergy said this week.

Pilgrim entered service in 1972 and is licensed to operate until 2032. Entergy announced in 2015 plans to close the plant permanently by 1 June this year. The plant is then to be sold to Holtec International for decommissioning.

"Since Pilgrim was already slated to be permanently retired by June, I'm sure some wondered whether we would return to normal oversight before shutdown," Brian Sullivan, Pilgrim site vice president, said. The "greatly improved" performance at the site was thanks to the "professionalism and pride" of the plant's employees and "strong support" from the company's nuclear division, he added.

The NRC describes its regulatory framework for reactor oversight as a "risk-informed, tiered approach" to ensuring plant safety. The framework identifies three key strategic performance areas of reactor safety, radiation safety, and safeguards. 'Cornerstones' in each area reflect the essential safety aspects of facility operation. The regulator uses information from inspections and performance indicators to draw objective conclusions about licensees' safety performances and to determine the appropriate level of agency response for each plant. Plants are then placed in the appropriate column of the NRC's five-column action matrix.

Annual letters issued to of the USA's operating nuclear power plants regarding their performance throughout the year are publicly available on the NRC's web site.

Researched and written by World Nuclear News