Three Workers Killed, One Missing in Tunnel Explosion
MILWAUKEE (AP) _ An explosion in an underground sewerage tunnel Thursday killed three workers who fled when methane gas built up, but then returned to check the gas level.
The deaths were the fourth, fifth and sixth fatalities in four deadly accidents on the tunnel project. The contractor in March was cited by the Occupational Safety and Health Administration for unsafe conditions, including poor ventilation.
Rescue crews were hampered by high levels of methane in the tunnel under construction 40 feet below ground, and special equipment had to be brought in to remove the gas and pump fresh air into the search area, said Deputy Fire Chief Norm Luedke.
The bodies of two workers were found about 2 p.m., five hours after the explosion or explosions, said Pat Freeman, corporate safety director for project contractor S.A. Healy Co. The third was found a short time later. A crane hoisted a stretcher bearing the final body from the tunnel shortly after 5 p.m.
″One of them was a real good friend of mine,″ Freeman said, his voice quivering.
The company identified the victims as Ron Kohne, of Big Sandy, Tenn., a tunnel superintendent; Tony Bell, of Sturgeon Bay, a shift foreman; and Rick Sochacki, of South Holland, Ill., a safety officer. All were believed to be in their 30s or 40s.
After the explosion, two rescue crews moved about 1,200 feet into the tunnel, but they turned back on detecting methane levels of 6 percent, said Luedke, who heads the department’s tunnel rescue unit. Any reading above 4 percent is considered dangerous, he said.
They returned when fresh air was pumped in and discovered the bodies.
The dead workers were trapped approximately 2,000 feet into the tunnel, said Deputy Fire Chief Orville Peterson.
Patrick Doig, project manager for S.A. Healy, said 10 men were in the tunnel when a monitoring device showed high levels of methane. All of the men left the tunnel, he said, and then three men went back in to check gas levels. That was when the explosion occurred, he said.
The three had hand-held methane detectors, but it was not known immediately whether they had breathing equipment with them, he added.
Freeman said he believed the methane that caused the explosion was naturally occurring, from decayed organic matter.
The collector sewer near the accident site had been evacuated repeatedly in the last week because of unsafe levels of methane, said Chuck Kennedy, a resident engineer with the sewerage district program.
S.A. Healy, of McCook, Ill., which is building the sewer under contract with the Milwaukee Metropolitan Sewerage District, was cited March 17 by OSHA.
OSHA Director Gerald Cunningham called the violation serious and the company was fined $620 for not providing adequate ventilation in part of a tunnel and for failing to ground electrical equipment.
Three workers were killed in the tunnel prior to Thursday, giving Milwaukee the worst fatality record in the nation per dollar spent on a deep tunnel project, said Joseph McKinney, executive director of the National Safe Workplace Institute in Chicago.
One man was crushed to death in a conveyor system, another was struck in the head by a falling rock and the third fell 156 feet from a cage to the bottom of a tunnel air shaft.
Chicago has had 10 fatalities on its deep tunnel project and Cleveland has had three, Kinney said. But both projects are further along in contruction, he noted.
Milwaukee Metropolitan Sewerage District spokeswoman Rosemary Murphy said the tunnel construction is part of a $2.1 billion project that will expand sewage collection and treatment of waste.