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AUSTIN EXECUTIVE AIRPORT
A History of Austin's Newest General Aviation Airport
R
on
W. H
enRiksen
Chapter 9
surrounding soil had sunk around 9 inches,
more than enough to shear the landing gear
off a fast moving aircraft.
The runway and taxiway were separated
by 225 feet of dirt and grass that looked like
an earthquake fault line after a mild tremor.
From above, the line of sunken earth and as-
phalt was as obvious as a roadmap. In fact, at
some point I pulled up satellite photos of the
airport using Google Earth--a virtual globe
and map application--that showed startlingly
vivid images of the settled runway and taxi-
way to anyone with a computer and fifteen
minutes to kill.
As near as anyone could tell, the source of
the trouble was water.
Austin had been drenched in rains from
August through September and all that water
resulted in tons of saturated, heavy earth. I
called Frank McIllwain at Garver Engineers,
who sent out a crew of soil specialists to test
the dirt in the affected areas. Much like our
`drainage culvert sinking problem,' Frank's
best guess was that someone had forgotten to
compact the soil as outlined in the construc-
tion drawings.
Next I hired a engineering firm with geo-
technical savvy, Rodriguez Engineering
Laboratories, to take more soil samples, and
based on the samples one of the engineers
discovered that the construction crew had
done some compacting, just not enough. It
appeared that Bobcat Contractors had com-
pacted the porous backfill about every 2 feet
(not every 8 inches as required), which would
have been fine if I'd planned to grow hay atop
the pipeline, but it didn't work so well to sup-
port a 30-ton corporate aircraft.
Once I gave Atmos Energy the bad news,
a couple of construction executives came
out to the site and took a peek at the dam-
aged taxiway. The taller of the two pulled out
a cell phone and rang their subcontractor,
Bobcat Contractors, who sent out a team to
look around. Bobcat Contractors had clip-
boards, calculators, and measuring devices
with them, and they came up with a figure.
It would cost around $90,260 to fix the mess.
The head man handed over the estimate with
no mention of who might have done what to
prevent such a thing or even who it was he
expected to pay for the repairs. In the end,
some higher-up at Atmos Energy suggested
that Bobcat Contractors fix the runway and
taxiway at their own expense, or the energy
giant might consider using another subcon-
tractor for subsequent jobs.
Repairing the Runway
In December more surveyors showed up to
mark the dig-site with little yellow flags stuck
into the ground every eight feet or so, outlin-
ing what was an impossible-to-miss sinkhole.
The plan was for Bobcat Contracting to dig up
the sinking dirt and perform the initial back-
fill and compaction. Then Cash Construction
would lay in a thickness of new lime-treated
soil, a layer of P209 crushed rock, and a new
cover of asphalt.
To make sure everything went according
to plan, I asked Garver Engineers to assign
an overseer, Johney Boles. I insisted that if