At the urging of federal regulators, technicians at Vermont Yankee are inspecting the plant to assess risk from severe floods and earthquakes.
The Nuclear Regulatory Commission required the inspections following the earthquake and tsunami that crippled reactors in Japan in March of 2011.
And at the same time the NRC outlined the new inspection requirements, the commission also gave Yankee good grades in a recent performance review
The NRC calls the post-Fukushima inspections "walkdowns." Spokesman Neil Sheehan says that means Yankee technicians will comb through the plant to look for potential vulnerabilities to natural disasters.
"An example of that would be: are there any gaps where severe flooding could impact equipment, any degraded flood barrier seals that might allow flooding waters to get inside the plant," he says.
Sheehan says the seismic part of the inspection will focus on plant components.
"They’re looking to see whether there’s any equipment that might not be anchored in the way that it should to withstand severe earthquake activity, earthquake activity that might not have been envisioned when the plant was built," he says.
Commission staff will then assess the information from Yankee and other reactors around the country and will make recommendations if retrofits are needed.
The NRC also gave Yankee relatively high marks in a recent review. Because the mid-year assessment did not find issues of major safety significance, the NRC will not step up the frequency or intensity of its inspection schedule.
Sheehan stresses the good marks – "green" findings in NRC jargon – don’t mean everything is perfect at Vermont Yankee.
"Green does not mean that there is no issue at all," he says. "It merely means that because of the low level of safety significance they’re going to get an opportunity to put it in their corrective action program, makes changes, and we’ll follow up to make sure that’s indeed what happened."
The NRC’s positive inspection report comes as the Shumlin Administration asked federal regulators to look at a string of human errors at the plant.
Public Service Commissioner Elizabeth Miller said in a letter to the NRC that the incidents, while minor if examined in isolation, taken together may indicate a more troubling pattern.
Her letter to the NRC last month pointed to a number of problems, including a pump failure, a faulty maintenance procedure, and a misaligned valve that allowed water to drain from a fuel pool.
Miller says the NRC’s way of categorizing these incidents means the errors are not always considered in total.
"While that’s understandable from their point of view, it’s also difficult from the public’s point of view to understand why errors that at bottom concern a human mistake, why those errors wouldn’t be lumped together and treated together for purposes of looking at inspections," she says.
A Vermont Yankee spokesman says plants officials were pleased by the recent NRC inspection. The spokesman says the report shows that Yankee has developed a strong culture of safety.