Horsehead Corp. will continue to pay all workers at its zinc plant in Beaver County, even though part of the facility has been shut down while investigators try to figure out what caused an explosion last week that killed two men.

A preliminary assessment of the damage indicates that the columns used to produce zinc oxide and refined zinc metal in the refining facility will need to be rebuilt before production can resume.

The company also said rebuilding will be delayed pending results of a federal investigation to make sure all safety measures are considered before production begins.

The investigation, headed by the U.S. Occupational Safety and Health Administration and the U.S. Chemical Safety Board, is expected to take several weeks. Horsehead said it may be several months before production is fully restored, but that everyone will remain on the payroll and continue to receive full benefits.

The plant, in Potter Township near Monaca, employs 600, with 105 in the refinery.

"We are committed to safety and restoration of our operating capabilities and are working hard to provide support to our customers," CEO Jim Hensler said in a statement.

While the smelting facility and other operations at the plant remain active, they are operating at a reduced rate. The smelting facility is operating five of its six furnaces producing zinc metal. The operating level of the smelter will be adjusted based on market conditions and as operations at the zinc refining facility are restarted, Horsehead said.

The financial impact of the accident isn't known yet, but Horsehead said it expects the cost of repairs and loss of revenue from zinc oxide sales during the rebuilding period will be partially offset by increased metal sales. The loss is also subject to recovery under the company's business interruption and property insurance. About 40 percent of the company's revenue comes from the sale of zinc oxide.

A blast at about 4:30 p.m. Thursday killed James Taylor, 53, of Aliquippa, and Corey Keller, 41, of Newell, W.Va. Both were pronounced dead at the scene about two hours after the explosion. Autopsies showed both died of asphyxiation from smoke inhalation.

Two other workers were hurt, one with scrapes and bruises and the other with a neck injury. Both were treated at a hospital and released.

The workers are members of United Steelworkers Local 8183 in Bridgewater, which has set up a fund for the families of Mr. Taylor and Mr. Keller.

In addition to OSHA and the Chemical Board, the company and the steelworkers union are investigating the explosion. The Chemical Board is an independent federal agency that investigates industrial chemical accidents and makes recommendations, but it has no enforcement power.

OSHA has jurisdiction over the investigation.

Horsehead employs about 1,000 workers at seven facilities in Pennsylvania, Oklahoma, South Carolina, Texas, Illinois and Tennessee.

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