| The RM Clayton construction shaft ( one of three Nancy
Creek Tunnel construction shafts) |
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| Tunnel diagram - the shaft is 130' deep! (and getting
deeper by the day) |
Looking down 130'
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| On the way down... |
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| The man-carrier basket |
A crane lowers the basket into the shaft |
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| Clair, Mary and Ed inside the basket, enjoying the
smooth ride |
Taro Nonaka - Obayashi
Tony Gomez - City of Atlanta
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Looking down from inside the basket
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The walls of the shaft are partially wet, principally
at 50' from surface, where the soil meets solid bedrock |
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| At the bottom |
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The crew was preparing to load explosives for another
round of blasting
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Holes drilled in the floor are marked with red plastic to
facilitate loading them with explosives
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It was generally dry at the bottom. A sump
pump sucked up what leakage there was coming from the sides of the shaft |
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Clair and Walda point toward Roswell Road
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View of the smallest of three tunnels being constructed
off of the main shaft |
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Visit to Roswell Road Construction Shaft Site
(2/5/03)
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| Looking across Roswell Road at the green sound walls
surrounding the construction site |
View at site looking south
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View at site looking north
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| Putting heavy blast-containment cover over explosives in pit |
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Blast cover (upper left: covered with black rubber
sheets) is being lowered by crane to cover pit
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Cover (covered with straw bales) is now in place.
The huge gray cylinder by the green fence in the
background is a form to be used to line the shaft with concrete.
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Under the cover: layers of steel mesh and 6' of dirt to
muffle the blast of 1,800 pounds of explosives buried in 120 holes in the
rock
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| Pulling the blast cord from the pit across
Roswell Road to Post Chastain |
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Once everything was ready, a worker unrolled blast cord
on his way across Roswell Road
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The blast cord burns at thousands of feet per second
when ignited
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Safely across Roswell Road at Post Chastain, with
traffic stopped by police, final preparations are made for the
detonation |
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| The detonation (no pictures) |
BOOM!
Actually, not really BOOM! The explosion was
certainly noticeable, but surprisingly un-noisy. The ground rolled briefly,
but distinctly -- Mike's people
checked their four seismographs and were apparently happy with the limited
ground shaking.
The crew was kind enough to let me (Gordon) set off the blast! I
stomped the igniter which lit the blast cord-- I never imagined I would
ever blow up a huge quantity of explosives! And, as Walda and I
said to each other, we have heard much louder car wrecks. |
