Tunneling work remains stalled on the 1.5-mile Baltimore Metro subway extension from Johns Hopkins Hospital to Charles Center while contractors install ventilation equipment needed to clear the fumes from gasoline-contaminated earth.
"I think it's unlikely we'll be tunneling again for the next couple of weeks -- the equipment is being installed now," said Peter J. Schmidt, assistant general manager for development at the Mass Transit Administration.
And he was unable to predict whether the tunneling halt will delay the opening of the $321 million extension, which is scheduled to begin carrying passengers in mid-1994.
Work continues on other parts of the project, including work on the Johns Hopkins Station itself and on short sections of subway track and utility tunnels just north of the new station.
Workers also have completed work on relocation of the Jones Falls conduit at Baltimore and President streets, and are continuing excavation on the Shot Tower Station.
But construction of the extension's two main tunnels has yet to get back to normal since a water main broke Nov. 15, producing a 15-foot-deep sinkhole on Orleans Street that forced the contractor, Kiewit/Shea JV, to halt tunneling.
No one was injured and the tunnel was not damaged, but contractors had to clear debris from the tunnel and repair the water mains before starting work again Dec. 3. Some telephone utility repairs continue, though the roads through the area are open, aside from one southbound lane of Broadway.
The project stopped again Dec. 18 when project officials decided that gasoline fumes in the tunnel from the contaminated earth were approaching toxic levels.
The gasoline probably came from a leaky tank at a service station once located at the corner of Orleans Street and Broadway, said Schmidt.
Contractors had noted some gasoline fumes late last year, but the fumes never reached a level that would be toxic to workers, who were using masks, said Schmidt. The fumes grew worse by late December, forcing the shutdown. Schmidt said the fumes ** never posed a danger of explosion.
The contractor now is installing larger ventilating fans than would normally be used for such a tunneling project, and 48-inch ventilating ducts to the surface. Those fans are to draw the contaminated air from the tunnel and flush it with fresh air from the surface.
At the time work was stopped, one tunnel had been dug to within several hundred feet of Fayette Street and another had advanced to the corner of Orleans and Broadway.
Schmidt said it was still uncertain what effect the delays may have on completion of the project. He said contractors could reschedule some parts of the project to keep work moving.
The project is being funded 85 percent with federal money and 15 percent with state money.
Contrary to previous reports, the project is fully funded in the fiscal 1992 budget and has funding guarantees for fiscal 1993, according to an MTA spokeswoman.