HOUSTON, Sept 10 (Reuters) - One of the United States' largest refineries was cutting back production on Tuesday as Tropical Storm Francine was forecast to past just east of its location, said people familiar with operations at Exxon Mobil Corp's (XOM.N) , opens new tab Baton Rouge, Louisiana refinery.

Exxon plans to cut production to as low as 20% of the Baton Rouge refinery's 522,500 barrel-per-day (bpd) capacity by Wednesday when Francine may roar ashore as a hurricane, the sources said. The refinery is the sixth largest in the United States.

An Exxon spokesperson did not reply to a request for comment on Tuesday.

Exxon and Shell Plc's (SHEL.L) , opens new tab 233,702-bpd Norco, Louisiana refinery were planning rely on "ridethrough" crews to operate the refineries during the storm's passage.

At the Norco refinery, all workers but the ridethrough crew were sent home at noon CDT (1700 GMT) on Tuesday, sources familiar with Norco operations said.

Shell confirmed in a statement posted on a company website that the refinery would rely on a ridethrough crew.

The company plans to maintain full production during the storm.

At the Baton Rouge refinery, the crew operating the refinery is scheduled to work 18-hour shifts during the storm, the Exxon sources said.

Marathon Petroleum Corp (MPC.N) , opens new tab declined to discuss plans for its 597,000-bpd Garyville, Louisiana refinery, the nation's fourth-largest, during the storm.

"We can say we have comprehensive plans and procedures in place to protect our people, assets, neighbors and the environment during severe weather," said Marathon spokesperson Jamal Kheiry.

The large refining units that convert crude oil into fuels, petrochemicals, lube oil and plastic feedstocks are able to withstand hurricane force winds and heavy rain. However, they are most often shut during tropical storms by disruptions to control systems and electrical systems from flooding or power outages in the communities around them.

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https://www.reuters.com/business/energy/exxon-louisiana-refinery-cuts-production-ahead-storm-sources-say-2024-09-10/