By Roger Alford
The Associated Press

CORBIN - Local leaders pledged their help in getting Corbin's largest factory reopened after an explosion Thursday that injured more than 20 workers and caused major damage to the building and machinery.

Ten employees from CTA Acoustics remained in critical condition Friday in burn units at the University of Kentucky Hospital in Lexington and Vanderbilt University Medical Center in Nashville. One of the injured employees was released from a Louisville hospital, and another was upgraded from critical to stable condition.

Brian Reams, public safety director for Laurel County, said the factory on the city's north side was not destroyed in the explosion and fire, which sent black smoke through residential areas.

An outer wall was bulging at the rear of the building. Some inner walls were knocked down. And authorities said they don't know when the factory, which makes insulation for the automobile industry, can reopen.

"We're going to do everything we can to rapidly and safely get CTA back in that building," Reams said.

Counselors from the Kentucky Department for Employment Services plan to begin meeting with workers next week to determine what types of jobless benefits they might qualify for, said Phyllis Patterson, an agency spokeswoman in Corbin.

"This has a tremendous economic impact," said Mike Patrick, judge-executive in Whitley County. "We're going to do whatever is necessary to get that plant back up and running. We've got to ensure that those employees have a place to work."

State and federal investigators have begun trying to determine the cause of an explosion and fire.

Carl Vasilko, an agent with the U.S. Bureau of Alcohol, Tobacco and Firearms, said investigators got into the building for the first time Friday morning.

He said they had interviewed several employees who were in the building.

"You get bits and pieces of information," he said Friday. "You can't make judgments on that."

Hundreds of nearby residents who had been forced out of their homes were allowed to return Thursday night after investigators determined that fumes from the fire were not hazardous.

Firefighters and contractors buried smoldering rolls of insulation to smother the fire. Reams said those rolls will later be dug up and disposed of properly.

Art Smith, an investigator with the U.S. Environmental Protection Agency, said smoke from the fire contained trace amounts of ammonia, far below levels that would be considered harmful. He said no hydrogen cyanide was detected in the smoke, as authorities had feared Thursday morning.

"The concentration of ammonia was 5 parts per million," Smith said. "Those concentrations are five times below what a worker would be allowed to be exposed to over an eight-hour period."

Reams said crews have placed booms and dikes along nearby streams to keep runoff from leaving the plant site.

"We don't expect any water problems," Reams said.

Inspectors from the Kentucky Cabinet for Natural Resources and Environmental Protection found elevated levels of phenol, a hazardous chemical compound, in water on and around the plant's property.

Mark York, spokesman for the state agency, said the phenol was "not at a level that constitutes an emergency to human health."

Jim Tomaw, legal counsel for CTA in Corbin, said the compound is in resin the company uses in the manufacturing process.

Tomaw said the fire began near a furnace where raw fiberglass is mixed with the resin and molded into sheets. He said 150 of the company's 561 employees were in the plant at the time of the explosion.

Tomaw said some employees reported being knocked off their feet by the concussion as it blew through the plant.

John Henson, administrator of Baptist Regional Hospital in Corbin said some of the injured were burned over 70 percent to 90 percent of their bodies.

"It would be impossible for me to describe the scene in that emergency room yesterday," Henson told reporters Friday morning, his voice breaking and tears pooling in his eyes.

The Corbin hospital treated 30 people, 10 of whom were later released. Marymount Hospital in London treated 14 people.

Some victims had to travel to University Hospital in Louisville by ground ambulance, because of inclement, foggy weather that prevented air transport.