The Point Lepreau nuclear generating station is back online after a two-week shutdown.
NB Power said the plant was taken off-line on Sept. 11 after monitoring elevated levels of tritium in the reactor building.
According to the utility, the source of the issue was an instrumentation line in the primary heat transport system.
The issue was contained and NB Power said there was no risk to the public or environment.
The plant came back online on Saturday.
