Employees of International Paper’s Vicksburg mill could return to work in about a month if repairs to the plant’s recovery boiler progress, plant officials said Monday.

That would be ahead of estimates for returning to full production following a deadly explosion May 3 at the Mississippi 3 facility.

“My plan is to make paper Sept. 25,” plant manager Tom Macher told Warren County supervisors, who approved up to $70 million in federal Gulf Opportunity Zone bonds to help finance the remaining repairs.

Restarting the boilers in the phased startup is planned for the third week of October, Macher said, adding the company’s goal is to return to full production by Nov. 1.

Calling workers back will be in line with union rules, he said, adding that unions represent about 80 percent of IP’s local work force. Meetings with union representatives were planned after the session with the county, Macher said.

One person was killed and 17 were injured when the explosion rocked the paper mill during the reported restart of a boiler after annual maintenance. All involved were contract workers. About 400 people, including IP’s 306 regular employees, were at the mill when the explosion occurred.

Inspectors with the Occupational Safety and Health Administration are looking into possible causes, with results expected by November.

Two unidentified contract employees remain in good condition and a third is in serious condition at the Joseph M. Still Burn Center in Augusta, Ga., a hospital spokesman said Monday. Two others were treated and released from the Georgia hospital within the past six weeks, including Kenneth Townsend, among three plaintiffs in separate lawsuits claiming negligence on the company’s part and seeking punitive and compensatory damages. Killed at the scene was Marcus Christopher Broome, 28. Other workers were taken to River Region Medical Center, treated and released.

Initially, it was not known whether IP would continue to operate the plant, which was immediately shut down with all except a few employees laid off. A company announcement that repairs would be made in about six months and improvements could continue was greeted with enthusiasm because IP is one of the oldest and largest local industrial employers.

Though company officials have not speculated on the total cost of rebuilding, the new round of tax-free, Katrina-inspired bonds will dovetail onto $50 million in bonds issued by the county in 2006 and 2007 aimed at financing infrastructure improvements. That money included boiler upgrades that were not completed, including replacing obsolete parts and structural materials.

Terms of the issuance call for the county to own the project for 10 years, then turn it over to the company. Local government acts as a sponsor in such actions. Any tax exemptions approved as part of subsequent agreements would not involve school taxes.

Projects planned before the explosion to install a new burner in the lime kiln and a storage silo for the petroleum coke that would fuel it are up for approval from the Mississippi Department of Environmental Quality. Those are scheduled to start in 2009, the company has said.

About 555,000 tons of linerboard used in corrugated packaging are produced annually at IP’s Vicksburg Mill, which began operation in 1967. The company lists 51,500 full-time employees worldwide.

IP shares closed at $28.36 Monday, down about 2 percent from Friday’s close. The Memphis-based company completed a $6 million purchase of the container board, packaging and recycling portion of Washington-based forester and timber producer Weyerhaeuser, a deal said to key in solidifying IP’s packaging business. It is still subject to closing costs.