AmerenUE reports “unusual event” at nuclear plant

FULTON — AmerenUE’s nuclear power plant in Callaway County remains fully operational after an “unusual event” was declared late Thursday night. No release of radioactivity resulted from the event, and neither the public nor the plant’s personnel were put in danger, a news release said.

According to AmerenUE, a water relief valve opened unexpectedly around 11:20 p.m., allowing an abnormal amount of water to flow into a collection tank. As of Friday afternoon, water was still being rerouted through an alternate system as officials were “reviewing repair options” for the malfunctioning valve, said plant spokeswoman Susan Gallagher.

An “unusual event,” AmerenUE said, is a term established by the U.S. Nuclear Regulatory Commission to “describe a relatively minor occurrence at a nuclear power plant that could reduce the overall level of safety.”

Last April, the plant declared an alert after an electrical fire erupted near a transformer. No one was endangered by the event, AmerenUE said.

Such disclosures of problems at the power plant are required by the Nuclear Regulatory Commission.

“Nuclear plants are under a very tight scrutiny by the U.S. Nuclear Regulatory Commission,” Gallagher said.

As of Friday afternoon, an investigation into the cause of the valve’s failure was ongoing.

The uranium-powered plant has been in operation since 1984 and generates enough power for about 750,000 households, according to the company’s Web site.

The plant is owned by AmerenUE, which provides power to areas in Missouri and Illinois. AmerenUE is a subsidiary of Ameren, which is based in St. Louis.