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Repairs in Downtown Subway Nearly Done : Transit: MTA believes it has corrected problem of thin tunnel walls. But questions linger about the work.

November 20, 1994|DAVID WILLMAN | TIMES STAFF WRITER

More than 2,000 tons of concrete material has been pumped to repair defective subway tunnels already open to passengers in Downtown Los Angeles, and engineering specialists say the work is nearly complete.

The repairs began in March after tests verified that numerous areas of the tunnels were built with concrete walls thinner than designed, were cracked or were leaking water.

"With the work that's been under way, I think we will come out with what we intended to purchase" when the tunnels were constructed, Franklin E. White, chief executive officer of the Metropolitan Transportation Authority, said in an interview. "The bottom line is, if we paid for it, we want it."

But questions have emerged regarding the tunnel construction and the scope of the recent tests and repairs performed for the MTA.

Some areas of the tunnels were not examined for concrete thickness, records show. And water entering the tunnels near Union Station was not sampled--although previous tests had found the area to contain the highest concentrations of corrosive, hydrogen sulfide along the subway route.

Transit officials hoped that the recent repairs would put to rest what White has called a "painful chapter" for the subway, which opened to passengers in January, 1993.

The Times reported in August, 1993, that sections of the concrete tunnels between Union Station and Pershing Square were built as thin as 4.87 inches--compared to the minimum designed thickness of 12 inches.

White appointed a panel of outside specialists in the fall of 1993 to examine the structures. The panel concluded in February that despite the deficiencies the tunnels would remain safe if the filling of voids in the concrete and other recommended repairs were performed.

Over the next eight months, the nation's newest subway was converted into a construction site.

During the late night and early morning, crews of seven men mixed thousands of bags of cement with water and other materials, then pumped it into the tunnel crowns to fill the air voids.

By day, the compressors went silent, but chalky grout that streamed from the tunnel walls onto the tracks can still be seen.

While the tunnel repairs were under way, other problems confronted transit officials: Sinkages occurred along Hollywood Boulevard, several miles away, damaging buildings and forcing a halt to the excavation. Citing displeasure with the project's construction quality, the Clinton Administration took the extraordinary step Oct. 5 of suspending $1.6 billion in future funding. The funding was restored Nov. 10 after the MTA dissolved its construction subsidiary, ousted the subsidiary's president and made other organizational changes.

Meanwhile, the FBI and the inspector general of the U.S. Department of Transportation pressed their investigations of the project. "The efforts we have ongoing with the subway will continue," said Lawrence H. Weintrob, deputy assistant inspector general for auditing.

People familiar with the inquiries say investigators are examining, among other things, the construction of the tunnels, including the installation of a protective plastic liner that has failed to shield the subway Downtown from water and potentially toxic and explosive gases.

The subway project's chief inspector has told a review panel that the liner was at times installed negligently, records show. The Times also reported in May that gas intrusions throughout the subway have forced the use of ventilation fans on hundreds of occasions.

White negotiated an agreement earlier this year requiring one tunnel builder, Tutor-Saliba Corp., to perform the repairs on 1.8 miles of the subway at no expense to taxpayers. But now, eight months after the work began, Tutor-Saliba is threatening to seek payment for some of its costs.

"It appears that our commitment to be a good corporate citizen has been taken advantage of," said company President Ronald N. Tutor in a letter this month to White. Tutor criticized the MTA for forcing his company to fill air voids at scores of locations, many of which had not been identified before the work began.

"We feel that this has been a research project at our expense," Tutor wrote. "This MUST stop!" Tutor told White he would inform him of the amount he is seeking from the MTA when the repair costs are totaled.

Tutor declined in an interview to estimate how much his company has spent on the repairs. Based on the price of the grout material and typical labor costs, experts estimated that the work to date has cost up to $1 million.

Tutor-Saliba and a joint venture partner built the twin tunnels between Union Station and Pershing Square and excavated the site for the Civic Center station for $89 million, or 45% over the competitive bid.

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