It could be several more weeks before the Point Lepreau Nuclear Generating Station returns to service, according to NB Power.

The facility was taken offline in early April for what was supposed to be a 100-day planned maintenance outage.

During start-up, the utility said crews discovered a “critical issue” related to the main generator on the non-nuclear side of the station.

“Once the initial issue was discovered with a stator bar within the generator, NB Power conducted extensive testing on all stator bars and identified that five others were showing signs of degradation,” the utility said in a news release.

“An independent investigation has determined that the cause of this issue is a manufacturer’s defect that occurred during the maintenance of the generator in 2010. ”

Officials said they had to “safely and meticulously” disassemble part of the generator assembly, including the removal of the generator rotor, in order to access the stator bars.

Repairs have been completed and crews are working to reassemble the generator, said the utility.

“This involves several verification steps and thorough testing to ensure that all components are precisely aligned and secured,” said the release.

“Once that is complete, in the coming weeks, we will begin start-up activities, including station equipment checks and testing protocol. ”

NB Power said it now expects the station will be back up and running in December, although the timeline will be determined by how the start-up activities progress.

While the full cost implications of the extended outage are not yet known, it costs NB Power an average of $900,000 for each day that Point Lepreau is offline.

“We are examining every option to reduce costs for New Brunswick customers, including exploring if these costs can be recovered through our corporate insurance policies,” said the release.