The U.S. Nuclear Regulatory Commission said it would adjust its Reactor Oversight Process starting in January by adding one more white-level inspection finding – going from two to three – that would be the equivalent of one yellow warning in its color-coded inspection matrix.
The NRC uses four colors to denote different levels of concern for findings in a nuclear plant inspection, starting with green. The next level of concern is a white warning, followed by yellow, then red, which denotes the most serious concerns.
The more serious color-coded inspection labels can move a plant from Column One, which reflects the highest safety and operations standards and which is reflected by what is termed normal oversight requirements. Plant inspections that include significant concerns can move the plant to Column Two, Three, Four and then Five, which is the highest level of concern and which requires an order to cease operations to address the issues.
The federal regulator said that it had a approved changes to the Reactor Oversight Process, adjusting the criteria for subjecting a nuclear power plant to additional oversight and directing the staff to develop new guidance to help identify weaknesses in a licensee's performance.
The recommendation for the change came from staff members who acknowledged that three low-to-moderate safety significance (white) inspection findings better matches up to one yellow finding, which can push a reactor into the “degraded cornerstone” category of regulatory oversight, often known as Column Three of the Reactor Oversight Process Action Matrix.
The Reactor Oversight Process (ROP), which has been in use for 15 years, assesses a nuclear power plant's performance across seven aspects of facility operation, each of which are deemed “cornerstones.” The color-coded performance indicators – green, white, yellow and red – are based on objective data regarding plant operations. These safety-significance numbers are compiled by the licensees and reported to the regulator.
Under the current process, a plant is moved to Column Three based on two white inputs in the same cornerstone or a single yellow input. But a staff review of the process determined that, from a “risk-informed perspective,” three white finding, not two, is a better match to a single yellow input, the NRC said.
The NRC said the move from Column Two to Column Three involved a “significant increase” in resources from both the agency and the power plant operators. It ups the game considerably.
In numbers, Column Two requires 40 additional hours of inspection compared to Column One. However, the move to Column Three triggers the need for 200 additional hours of inspection.
Bill Dean, director of the NRC's Office of Nuclear Reactor Regulation, said the change would allow the agency focus on the more critical problems that arise. The adjustment would “help us target our oversight more precisely on those plants with significant performance issues,” Dean said.
The change, the NRC said, does not alter the oversight status already established for the various plants around the country.