DTE seeks to downplay incident at Fermi II nuclear power plant

An incident involving a nuclear reactor going into “hot shutdown” at DTE Energy’s Fermi II power generation station in Monroe County late last month went largely unnoticed locally and is raising questions about what exactly happened at the plant.

DTE officials have minimized the incident, stressing that it’s dangerous to make assumptions about the safety of the reactor after high vibrations from a bearing in the plant’s main turbine caused operators to manually switch the reactor into shutdown.

According to a report by the plant to the Nuclear Regulatory Commission, the 1,100 megawatt boiling water reactor was operating at 23-percent power on March 28 when at 1:46 a.m. the shutdown began.

The plant was running at the reduced power level as part of a ramping down of operations in advance of a planned shutdown for refueling and maintenance.

“The cause of the high main turbine vibrations is currently under investigation,“ according to the report. “There was no maintenance or testing in progress that would explain the high turbine vibration levels.”

The report went on to state that the lowest reactor water level reached during the incident was 162 inches, and “[a]ll isolations and actuations for reactor vessel water level 3 occurred.”

“As you shut down the reactor quickly the pressure becomes higher and the water level goes down,” said Viktoria Mytling, a Nuclear Regulatory Commission spokeswoman. “The reactor water level does go down a certain amount as a consequence of a SCRAM [sudden shutdown]. What happened at Fermi in terms of the water level going down was expected.”

Mytling said that the normal reactor vessel water level is 197 inches and the minimum level is 150 inches.

Although the NRC reports that lowered reactor vessel water levels are an anticipated result of sudden plant shutdowns, DTE spokesman John Austerberry cautioned Michigan Messenger against reporting about the drop in water levels during the incident.

Asked about the low reactor vessel water level included in the shutdown incident report, Austerberry said: “I think that was just a data point we were providing them. I don’t think it necessarily indicates that there was any loss of water level at all. So I’d be very careful about that.”

“The ‘scramming’ of a nuclear reactor is a little like hitting your breaks on the interstate,” said Paul Gunter, a policy analyst with the nuclear watchdog group Beyond Nuclear. “It tests a lot of systems and puts systems and components under a lot of stress. It does put a lot of wear and tear on the system.”

Michael Keegan, a nuclear power critic who lives near the Fermi II plant said that he learned of the incident through a notice on the NRC website.

Keegan, who is among the individuals trying to block the construction of an additional reactor at the Fermi complex, said that locals are “salivating” at the prospect of jobs in building the new plant. He said that he finds the lack of local media on the situation disturbing.

“It’s kind of peculiar,” he said. “You see [this incident] is picked up by Reuters and you can read about it in New York but you can’t read about it in your home town.”

The Toledo Blade published an article about the “erratic vibration.”

Keegan said incidents at the plant have led to serious environmental issues.

In 1993, a turbine problem on Christmas Day led to a fire which resulted in the radioactive contamination of more than a million of gallons of water that was subsequently released into Lake Erie.

Jim Riccio, a Greenpeace nuclear policy analyst said he is not surprised that a utility spokesman would try to play down a drop in reactor vessel water levels.

“He wants to make you believe that splitting atoms is something safe, but its not,” Riccio said. “The risk is that if the water levels go too low you uncover the core and you start to melt down, that is what happened at Three Mile Island,” referring to the 1979 partial core meltdown at the nuclear power station near Harrisburg, Pa.