The Palisades nuclear plant in Michigan has returned to service following an unplanned outage to fix a water leak.The 778 megawatt pressurized water reactor was operating at 22 percent power Wednesday, according to the Nuclear Regulatory Commission. Operators had shut the plant down on June 12 when leakage at 31.4 gallons per day from the safety injection refueling water tank exceeded a regulatory limit, according to an agency event report. The collected water, with minor tritium contamination, was pumped into a holding tank and did not pose a risk to the plant or the public, according to the report.An Entergy spokesman told the Holland Sentinel that plant personnel had been monitoring the leak since April 28. The utility made repairs to the 300,000 gallon aluminum tank that facilitates the removal of spent fuel and can serve as a backup source of water in an emergency.