Shell Oil Co. has agreed to sell its Bakersfield refinery to Flying J Inc., a privately held retail distributor of diesel fuel.

The sale, announced Monday by Shell, is expected to be completed in the first quarter of 2005, pending regulatory approvals. Terms were not disclosed.

The 73-year-old Bakersfield refinery, which can process up to 70,000 barrels of crude oil per day, turns out primarily gasoline and diesel fuel. It was slated for closure in March over Shell’s concerns about upgrading the facility. The Environmental Protection Agency had stepped in when Shell announced plans to close the facility by October 2004, working out an extension until March 31. The intervention of the California attorney general’s office helped coax a commitment from Shell to offer the plant for sale.

In mid-December, Shell said that negotiations with an undisclosed bidder for the refinery had broken down. At the time, the Oil Price Information Service reported that New York-based private equity investing firm Kelso & Co. was the leading bidder.