Boron-Water Leak Closes Indian Point Unit 3

CORTLANDT, NY — The discovery of a small leak at Indian Point Unit 3 caused operators to shut the unit down Friday night. The leak was on a line in the safety injection system (boron can be injected into the coolant for neutron absorption).

According to the Nuclear Regulatory Commission, Unit 3 was taken out of service after a plant operator identified a deposit of dry boron indicative of a leak on a line that is part of the safety injection system where it is connected to a boron injection tank.

Water that contains diluted boron (~2,500 parts per million) leaked from a tank, Entergy officials said.

The NRC said:

Based on the amount of dry boron found, the leak is believed to be small. However, because this problem could affect the operability of safety injection pumps, plant operators determined a shutdown to conduct repairs was necessary.

NRC staff, including our Resident Inspectors assigned to Indian Point on a full-time basis, will closely follow Entergy’s repair plans and planning to return the reactor to service. Our Senior Resident Inspector for Indian Point was on hand to observe the shutdown, and at other times during the weekend, and did not observe any immediate safety concerns. The shutdown was performed without any problems.

The safety injection system is part of a redundant emergency core cooling system. It is the intermediate pressure, intermediate volume portion of the emergency core cooling system. Pumps and piping are available to supply water to the reactor in case of an actual leak in the reactor coolant system.