On
a cold, crystal clear Sunday morning, with local television
helicopters jockeying for position in the sky, NADC-members
Geppert Bros. and Controlled Demolition Inc. (CDI) imploded
the three 17-story towers that made up a portion of the Mill
Creek Apartment complex in West Philadelphia.
Built
in 1954 at the corner of 46th and Fairmount Streets, near
the University of Pennsylvania, the Mill Creek complex covered
over 13 acres with three high-rise towers and 265 garden apartments
in 60 low-rise buildings.
Starting
on September 1st, Geppert Bros. began the preliminary work
of cleaning out the tower apartments while subcontracting
the asbestos abatement in the low-rise structures. In addition
to the structural demolition, Geppert Bros. is responsible
for all the sitework and the removal of underground storage
tanks at the complex.
The three
towers were constructed of reinforced concrete. Drilling and
removal of certain structural components in the three towers
was done by CDI in preparation for charging the buildings
for implosion. Workers drilled some 600 holes in the three
buildings and loaded 136 lbs. of explosives to bring the three
towers down. A five-person team worked with Geppert Bros.
personnel to prepare the towers in approximately 4 weeks.
The blast team used eight delays of 2.5 seconds to allow the
towers to fall one right after another. Charges were placed
on the second, fourth, eighth and twelfth floors of each tower.
Two towers were felled in order to "spread out"
the materials, facilitating debris removal. One tower was
brought down in a more vertical fashion so as not to pile
up debris from one tower on top of the other.
At
a little after 8:00 AM on Sunday, November 24th, dignitaries
from the Philadelphia Housing Authority and local neighborhood
groups, pushed a ceremonial plunger to set off the charges.
The three towers slid down upon themselves, ready for processing
and recycling.
Geppert
Bros. Superintendent Jim Sirianni believes that the three
towers will generate approximately 13,000 cu.yds. of material.
Geppert Bros. intends to demolish the remaining low-rise units
conventionally. They expect to bring their brand new Eagle
Crusher plant, which they used at the site of the Philadelphia
Navel Hospital implosion last year, to Mill Creek to process
the concrete generated there.
Geppert
Bros.' Dick Geppert explained that his company has 215 days
to complete the entire project and that they believe they
will be done well ahead of schedule. Private developers plan
to build some 500 new homes on the site, revitalizing the
West Philadelphia neighborhood.
