Dominion Resources is taking the prudent approach, albeit with a push from the state, in conducting ultrasound testing of a key component in the Unit 2 reactor at Millstone Power Station. The pressurizer contains parts manufactured at the Le Creusot Forge in France. The company is under investigation by French nuclear regulators for producing substandard parts and falsifying documents to cover its tracks.

The testing planned at Millstone would reveal flaws or cracks which, while invisible to the naked eye, would bring the safety of the equipment into question.

Disconcerting, however, is the decision of the Nuclear Regulatory Commission not to require such testing at the 16 other U.S. nuclear plants using parts made by the French company.

It appears Dominion’s decision may be as much political as safety driven. Officials in the Radiation Division of the state’s environmental agency urged the testing. It comes at a time when Dominion is asking the legislature to alter power sales regulations to improve Millstone’s competitive position. In other words, it is a time to stay in the good graces of state regulators.

Interestingly, Dominion has not announced plans to test Le Creusot-produced parts at its North Anna or Surry nuclear plants in Virginia. The parts there are three reactor vessel heads, replaced in the early 2000s after problems with the prior massive caps that seal the reactors and their nuclear fuel rods.

Richard Zuercher, communications officer for Dominion's nuclear division, said that the company agrees with the NRC that there is no need for additional testing.

"Basically, we're doing it because the state of Connecticut asked us to do it," said Zuercher of the testing at Milltone.

In a Feb. 23 letter to Daniel Doorman, NRC regional administrator for Region 1, Connecticut’s deputy environmental commissioner Michael Sullivan made it clear Connecticut was not comfortable with the federal agency’s no-testing stance.

Given “the potential public health and safety implications of any increase in the probability of failures associated with reactor coolant pressure,” Sullivan stated in the letter, Connecticut would welcome “additional assurance of safety … through nondestructive examination.”

“We let our technical opinion be known that we felt relatively strongly that this would be a good … and prudent step given the opportunity they would have,” said Jeff Semancik, director of the Radiation Division at the state environmental agency, when questioned about what led to Dominion’s decision.

That opportunity is the refueling outage underway at Millstone 2 in Wateford.

It is highly likely the independent contractor doing the testing will find nothing. That is certainly what the NRC expects. In deciding not to order inspections, the watchdog agency notes that the components have long been in use with no problems. The pressurizer at Millstone dates to 2006. Inspectors periodically check the components of all nuclear plants and have seen no issues with the Creusot products, said Neil Sheehan, a spokesman for the NRC.

But why not err on the side of caution by doing a more in-depth inspection everywhere, as Dominion is planning at Millstone?

The role of the pressurizer is maintaining sufficient pressure to prevent coolant water, superheated by the nuclear fission process, from boiling, even as it reaches 350 degrees centigrade, 3.5 times the boiling point under normal conditions. Failures in a pressurizer and the resulting loss of coolant were major contributing factors in the worst reactor accident in U.S. history, at the Three Mile Island plant in Pennsylvania in 1979.

If testing finds problems at Millstone 2, the NRC would have to re-evaluate its no-testing-needed stance. If so, thank Connecticut. After past safety problems at Millstone under prior ownership, which led to the NRC in the 1990s ordering the temporary closure of all three reactors operating at the time, the state created the Nuclear Energy Advisory Council. Working with the Radiation Division, NEAC’s job is to monitor and question Millstone operations. This added oversight is not seen in other states, which generally leave all monitoring to the NRC.

Given this decision at Millstone, the additional oversight is still working well.