- The Washington Times - Monday, December 24, 2001

Removal of the crushed shambles that was the World Trade Center is half-finished and will be done many months ahead of schedule, New York's man in charge of the effort says.
"The goal right now is to wrap up by May 1 subject to recovery operations from voids and pockets where they're finding bodies and remains," said Daniel A. Cuoco, the forensic engineer city officials called in to run the emergency clearance and to safeguard subways, nearby buildings and a property some now consider a shrine.
His May 1 goal is dramatically earlier than initial projections of 12 to 18 months, which would have stretched into March 2003.
Once the debris is cleared away, "somebody's going to have to make a decision what's going to be put there," Mr. Cuoco said in an interview.
On September 11, he was on the telephone offering help to the Port Authority when colleagues watching from the roof outside his office window screamed that the South Tower was falling.
City officials summoned him a few hours later to direct an excavation task estimated to cost $2.5 billion, more than twice what the twin towers cost to build.
Mr. Cuoco's forces removed half the debris in the first 100 days, the same time it took fires to burn out in an area known as the "bathtub," whose wall wraps 3,000 feet around the basement and is anchored to bedrock 70 feet below.
Fire department officials announced Wednesday that the fires that once raged inside the debris had been reduced to scattered hot spots. In addition to fires, flooding also was a danger at the site now known as ground zero.
Pumps reduced the water table 15 feet, and careful shoring of the bathtub helped contractors under Mr. Cuoco's direction keep the Hudson River from pouring in through the 3-foot-thick "slurry wall." That kind of flood would fill a foundation big enough to float two U.S. aircraft carriers side by side.
"If there was any breach of the slurry wall the Hudson River would end up in the excavation and then find its way through the subway tubes to Jersey City," said Mr. Cuoco, president and managing principal of LZA Technology.
That subway tube for the Port Authority Trans-Hudson line to New Jersey was plugged with a concrete cork on the Jersey side in case of flooding.
The tunnels used by the No. 1 and No. 9 lines on the IRT subway built in 1904 and the city's oldest were penetrated by falling beams. They also have been plugged with concrete until repairs are made. Those lines are outside the bathtub and, according to Mr. Cuoco, unlikely to flood even if the wall failed.
In another near-miss, contractors worked with LZA's platoon of 35 engineers to shore up the bathtub's south wall after being tipped off by a gap tearing open Liberty Street.
Sections of the massive foundation started to lean toward the building's wreckage in the open pit. Surveys showed that the wall shifted 4 inches before it was discovered. It tipped a foot out of line by the time it was braced and backfilled with sand to hold it.
"The debris was holding the wall back," Mr. Cuoco said.
He said concrete slab floors of the basement garage braced the walls for almost 30 years, but those floors were crushed out of position. Tieback anchors drilled through the bathtub walls during construction were cut when the basement was built, so 900 to 1,000 new anchors are being drilled into place to hold the wall in place as the hole is emptied.
"We didn't want to disturb anything because we weren't sure what was holding the wall up," Mr. Cuoco said. "Right now the goal is to continue with the excavation and get to the point where there's a stable hole."
A city as intricate as New York cannot simply shut down, so when officials invoked emergency powers to seize the disaster site, Mr. Cuoco took responsibility for deciding when city services could resume safely.
He addressed fears that rumbling subways on undamaged lines might cause new damage to buildings that stood nearby.
"We set up some seismographs near the buildings that had some damage and ran empty test trains through at 15 miles per hour while we measured the vibrations," Mr. Cuoco said.
The risk proved so negligible that trains operated briefly with a 15 mph speed limit before normal procedures were restored.
Mr. Cuoco's engineers designed supports and runways to get 30 cranes, including one capable of lifting 1,000 tons, to the site. The cranes ensure that demolition won't cause new damage, including techniques used to cut down the 200-foot steel section of the north facade intended for a memorial.
"From the start we didn't have any home at the job. We had to walk in, from our offices at 20th Street and Sixth Avenue, talking our way past police barricades," Mr. Cuoco said.
The city's Department of Design and Construction arranged office space on the 30th floor of the evacuated American Express Building at the adjacent Three World Financial Center.
But Mr. Cuoco's crew now is down to six engineers in the daytime and three at nights.
At first the city's design and construction engineering team worked outdoors along with four major contractors AMEC, Bovis Lend Lease, Tully Construction, and a joint venture by Turner Corp. and Plaza Construction. Aggressive overtures by Bechtel Corp., the world's largest contractor, to take over the job were rejected last week.
"The city's now at the point where they're ready to start turning some of these buildings back to their owners," Mr. Cuoco said of surrounding office towers, including One Liberty Plaza and Three World Financial Center, which were said by television news reports to be on the verge of collapse in the attack's aftermath.
Mr. Cuoco is a born-and-bred New Yorker a Bronx native who attended the elite Bronx High School of Science, graduated from City College of New York, and received master's degrees from New York University and Adelphi University in Garden City, N.Y.
Before September 11, his career highlight was analysis of the 1987 collapse in Bridgeport, Conn., of Lambience Plaza, a pair of 16-story buildings that fell during construction.
"I've worked on interesting designs and high rises everywhere, but this is the most important job that I have worked on and ever will work on," he said.

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