Irving Oil Ltd. will undertake annual fall turnaround activities starting in September at the operator’s 320,000-b/d St. John refinery in the eastern Canadian province of New Brunswick.

Slated to come offline beginning on Sept. 8, the refinery—Canada’s largest—will undergo mechanical works associated with the routine maintenance event from Sept. 11 through Nov. 8, Irving Oil said on its website.

The operator said it expects the refinery to resume operations beginning Nov. 18.

Irving Oil has yet to disclose details regarding specific works scheduled to be completed during the nearly 2-month turnaround.

In 2025, the operator invested nearly $40 million on the Saint John refinery’s Operation Eastern Screech Owl 30-day turnaround, works of which were to include infrastructure replacements, equipment upgrades, and comprehensive inspections of the complex’s piping and key units.

The 2025 turnaround was executed alongside the operator’s $100-million investment to upgrade the refinery’s fluid catalytic cracking unit (FCCU) that began in June 2025, the operator said.

To be completed in a phased approach over second-half 2025, Irving Oil said the FCCU revamp project was to involve a series of substantial upgrades to the unit aimed at maximizing performance and enhancing efficiency and reliability of the unit.

Further details regarding the status of the FCCU upgrading project have yet to be revealed by the privately held company.