(AP) -- Federal nuclear safety inspectors are investigating a radioactive waste leak at a Fairfield County nuclear power plant.

The State reports Tuesday the U.S. Nuclear Regulatory Commission says about 100 gallons of liquid waste spilled at the V.C. Summer plant operated by South Carolina Electric & Gas.

The NRC says the leak was discovered last week. State, federal and company officials are still investigating but say they have found no signs the material left the plant or threatened the public.

Nuclear plant pipes are under scrutiny in the wake of an Associated Press report that radioactive tritium has leaked from three-quarters of U.S. commercial nuclear power sites.

Officials say tritium has been found in groundwater at other South Carolina plants, but it's not known if tritium was released from V.C. Summer.

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