TOLEDO, Ohio (AP) — A FirstEnergy Corp. subsidiary said Thursday that they discovered and contained a pinhole-size leak spraying radioactive coolant at their Davis-Besse nuclear plant in Ohio.

Nuclear regulators and plant operators said the leaking coolant at nuclear plant near Toledo never got outside the building and posed no threat to the public.

Workers discovered the leak Wednesday as they were getting ready to restart the plant after a monthlong maintenance shut down.

A spokeswoman for the plant said they don't know how much coolant spilled out, but it was contained by its collection system.

The plant was last shut down in the fall while its reactor head was replaced. Crews found cracks in an outer concrete wall but the plant was allowed to restart.

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