The Nuclear Regulatory Commission recently announced disposition of several regulatory issues from Oyster Creek Generating Station’s fourth quarter inspection report. Without context, one might be alarmed by multiple violations in one reporting period, however a thorough understanding of the NRC’s Reactor Oversight Process provides the right amount of perspective.
In the United States, the safety of commercial nuclear power plants is assured by several layers of protection. Beginning with robust designs and stringent procedures, plant owners like Exelon enforce high standards on the hundreds of professionals who contribute to the design, maintenance and operation of their plants. Those standards demand compliance with federal safety requirements and more. Constant scrutiny and continuous learning are important parts of those high, self-imposed expectations. When minor lapses in performance occur, it is quite common for the owner (“licensee” in NRC’s parlance) to uncover the problem first, and, as appropriate, report it to NRC and fix it.
Equally important is the assurance provided by a strong, independent regulator. In the United States, that is the Nuclear Regulatory Commission (NRC). The NRC’s Reactor Oversight Process (ROP) is the agency’s program to inspect, measure, and assess the safety and security performance of operating commercial nuclear power plants, and to respond to any decline in their performance. The ROP includes specified continuous and periodic inspections and performance indicators that are reported to NRC quarterly. The inspection results (“findings”) and performance indicators are graded on a color-coded scale so NRC can more easily combine them to form a whole picture of the plant’s performance. The grading and color-coding also facilitate communicating the NRC’s perception of the plant’s performance to the public, the media, and other stakeholders.
An important premise of the ROP is the understanding that most of the time inspection results and performance indicators will show the desired “Green” grades. Lapses from this high level of performance are expected to be more or less random, and promptly addressed by the plant’s corrective action process. Sometimes, due to the timing of particular NRC inspections or publication of inspection reports, the NRC may seem to be releasing an apparent “cluster” of adverse performance results on a particular plant.
|Oyster Creek Generating Station|
This can give a misleading impression of a sudden decline in plant performance. To address this “lumpiness” of input data, the ROP framework specifies that the NRC’s comprehensive semiannual review of plant performance should encompass at least 12 months of performance data. In addition, the ROP provides for special inspections to dig deeper into the causes and corrections of individual lapses that are graded as more safety-significant than the random “Green” result. Thus, NRC will mount special inspections to follow up on the White and Yellow inspection findings, as well as the White performance indicator recorded in the third quarter of 2014.
Oyster Creek was judged to be operating at the highest levels of the ROP for most of the past five years. As Exelon responds to the current set of inspection findings and NRC follow-up, we have every reason to expect that Exelon’s response to the findings will underscore their commitment to improve performance in those areas.