A mix-up between radiation detection figures at Plant Vogtle will garner an official violation warning for operating company Southern Nuclear, according to a letter delivered by the Nuclear Regulatory Commission.
The letter, dated Feb. 8, highlights findings from an NRC inspection of the facility and its procedures in December. It said that “from October 2014 to October 2016, the licensee (Southern Nuclear) failed to maintain the effectiveness of their emergency plan and a standard emergency classification scheme.”
According to NRC documents, radiation detection numbers in two different air ventilation systems were switched. The switch raised radiation threshold numbers to a level 42 times higher than they should be for exposure and inversely 42 times lower in a vent system that would generate protective action recommendations to the public. The violations were found at Units 1 and 2; Units 3 and 4 are still under construction.
That means that in an emergency situation, radiation levels in one ventilation system could be much higher than warning levels. At the same time, more sensitive numbers in the other ventilation system would eat up a lot of response time by generating public safety notices for radiation levels that were actually too low to require such action.
A Georgia Power spokesman said, “Because of the additional redundancies in our monitoring systems, in an actual event, our ability to respond would not have been inhibited in any way.”
Consistent with NRC regulations, each of our radiation monitors are designed to provide independent detection capabilities. In the case of an event, there are multiple actions operators would take in order to ensure the safety and health of the public,” he said.
The letter told Southern Nuclear that the NRC is planning to issue an official color-coded violation. It said the violation is currently considered a “white” violation, but the NRC said the color could be changed before the official violation notification is delivered.
The violation scale is established in order of severity with violations being green, white, yellow, or red. Green is very low risk and a white violation is considered low to moderate safety significance, according to the NRC website.
“The performance deficiency was determined to be more than minor,” the NRC wrote in the letter. The commission’s letter showed that the violation wasn’t itself an emergency but that emergency response would have been drastically inhibited by the flip-flopped figures.
The NRC noted that Southern Nuclear “took immediate corrective actions” and provided the correct figures to its managers and decision makers.
“Our top priority is the safety and health of the public and our employees. We are committed to the safe operation of our nuclear generating facilities with equipment and systems that meet strict NRC safety and design regulations,” said Georgia Power spokesman Craig Bell.
The initial “white” classification is subject to change. The NRC letter said the commission is considering an escalated enforcement. The NRC has 90 days from Feb. 8 to issue its final determination. Georgia Power also has the option of challenging the finding before that 90 day window closes.
Reach Thomas Gardiner at (706) 823-3339 or firstname.lastname@example.org.