Rinaldi nods to the guards in front of the tall, chain-link fence.
They allow him to pass through the gate. Inside, a
huge canyon stretches for blocks and American flags hang everywhere.
On Sept. 11, 2001, when terrorists flew two commercial jetliners into
the twin towers of New York's World Trade Center and obliterated
them, Rinaldi was on vacation. That holiday break probably saved his
life. Rinaldi, 54, is an engineer for the Port Authority of New York
and New Jersey. His offices were on the 72nd floor of the North Tower.
had precious little time to reflect on his fate. He was named lead
engineer and oversaw the recovery and cleanup of the
WTC, managing a team of some 100 engineers and demolition experts. Rescuers
were still frantic that survivors might be buried in the ruins, and the
police and fire departments wanted to recover their dead comrades. But
the dangerous conditions threatened to take more lives. It was
unprecedented complexity, Rinaldi says. We were learning
as we went.
The rubble resembled a giant game of pick-up sticks, Rinaldi
says, with debris and steel building walls tangled up to 250 feet in
the air across a length equivalent to three and a half football fields.
Rinaldi and other engineers risked their lives while tunneling beneath
the surface through smoldering, partially collapsed basement floors,
and floating through flooded train tunnels on rubber rafts. He recalls
seeing five stories of the North Tower, with layers of floor, rug, cement,
and steel compressed into 2 feet, looking like soil stratum. But the
forays underground were necessary to diagram maps of the disaster to
indicate dangerous zones.
Those maps helped identify dangers that could have thwarted
the cleanup, such as a potential collapse of the 70-foot-deep concrete
walls that held back groundwater. Nearly nine months and 108,342 truckloads
of debris later, a final steel column was removed from ground zero, completing
the cleanup phase. But there is still much to do. Now Rinaldi is helping
solidify the foundation that will house the new buildings that will rise
from the ashes of the twin towers.
Bronx native majored in civil engineering at Manhattan College. He
later earned a graduate degree at Polytechnic Institute in
Brooklyn, where he specialized in geotechnical engineering, which has
to do with foundations, soil mechanics, and earthworks. His interest
stemmed from the fact that soil, rock, and water don't have the
same predictable behaviors as manufactured materials like concrete and
steel. There was room for judgment and creativity, he says.
After graduating, Rinaldi served as an adjunct professor
for many years at Manhattan College, teaching soil mechanics and fluids
as well as classes in earth pressures and retaining structures. But the
demands of his job with the Port Authority became too much and he gave
up teaching about 15 years ago.
trade center site was too dangerous to allow engineering students to
view the cleanup efforts until most of the debris was removed.
But now classes are starting to come. Since buildings are rarely unbuilt in
such a violent manner, Rinaldi says the disaster is unlikely to ever
make a university case study, but there are lessons for students to learn
from the experience. It's probably unique in terms of the
circumstances, he says, but not so unique in the skills and
experiences you need to have.
and police have been widely hailed for their bravery during the response
to the disaster, but engineers played a crucial
role, too. Unlike precise, methodical desk-bound engineering, this job
required engineering in action. What we had to do was not found
in engineering books, says Rinaldi. We needed experience,
intuition, and analysis, and a lot of professional judgment. Thanks
to his experience and training, no lives were lost during the recovery