The Nuclear Regulatory Commission reported an "unusual event" at FirstEnergy's Beaver Valley 2 nuclear reactor early this morning when leakage of reactor coolant into the plant's pressurized relief tank occurred. No radioactive release occurred at the plant in Shippingport, the NRC said.

An unusual event is the lowest of four NRC emergency classifications. The commission said the leak event was discovered at 3:05 a.m. and ended at 4:04 a.m. when the flow into the tank was stopped.

According to the NRC, the leakage occurred at a rate of more than 25 gallons a minute. The commission said its senior resident inspector reported to the site to monitor the company's handling of the event and any follow-up actions.

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