The Palisades nuclear plant in Michigan recently shut down to repair a minor cooling water leak.
Spokesman Mark Savage said no radioactive materials were released and that the leak was being repaired inside a containment building in the plant.
"Palisades is taking this conservative measure at this time because of our unrelenting commitment and focus on nuclear safety," said Savage. "Palisades will be returned to service when repairs are completed."
Chilled water is used to cool off numerous components in a nuclear reactor. The Palisades reactor was shut down June 12 to fix a leak in a refueling water storage tank. The plant was reopened on July 11. Savage added, in an unrelated incident, levels of cooling water slowly began increasing.
Shutting down the plant allows the radiation levels to drop so the foundation leak can be fixed. Palisades has been named by the Nuclear Regulatory Commission as one of the four worst performing nuclear plants in the nation, coming under recent public and governmental scrutiny.
Michigan health officials reminded people who live and work within 10 miles of Palisades to have potassium iodide pills, which prevent illnesses associated with radioactive iodine, in case an accident were to occur.