Fort Calhoun Update:
Underground Operations
to Begin by Late Fall
Jeffrey Green (left) and Phyllip Bowers inspect recent work at Fort Calhoun.
It’s hard to visualize the total investment
and harder still to comprehend
the project’s true scope. Yet, as work
continues at Nebraska’s Fort Calhoun
Quarry, the mission is clear to all involved:
Make it safe. Make it right.
When limestone starts flowing from
the underground later this year, Fort
Calhoun will become the Midwest
Division’s 10th underground mine. Still,
the site represents a first. Never has a
divisional team opened such an operation
from a greensite. Des Moines District
Vice President-General Manager Todd
Clock says project planners are taking
advantage of the opportunity.
“We’ve pulled together our underground
managers and discussed the
positive and negative aspects of every
underground we have,” he says. “We
took every factor into account. Our goal
is to design and operate the safest mine
possible while still being productive
and profitable.”
Project Manager Phyllip Bowers,
the engineer responsible for overseeing
the site’s transition, says the final
underground design is not yet solidified
but that the conceptual plan calls for a
primary – and likely, secondary – crusher,
two surge bins, a large feeder and five
conveyors. The goal, he says, is to
produce as much rock as possible while
conforming to the site’s existing aboveground
system.
Though engineering and excavation of
the mine have presented some minor
obstacles, Bowers says the bulk of his work
to date has been regulatory in nature.
“The big challenge,” he says, “was
understanding what we had to do to be
in compliance with MSHA. We had to
make sure they were aware of what we’re
building, what it will look like and what
provisions we’ve taken to ensure the
safety of our teams and our contractors.”
Bowers says that while Fort Calhoun’s
underground is expected to produce
rock before the end of the year, the first
Martin Marietta crew to head into the
mine will have to work for 18-24 months
before the site is fully operational. Plant
Manager Jeffrey Green says that the
12-member crew – dubbed the Pioneer
Team – has been training for their
new work environment and is up for
the challenge.
“When we put this team together, we
looked for people who really wanted to
be in on the beginning of something
big,” he says. “We’ve assembled a group
that wants to stand out and wants to be
involved.”
Bowers, who joined Martin Marietta as
a management associate, says moving
the quarry underground is a truly unique
venture.
“This is a once-in-a-lifetime opportunity
for me, personally,” he says, “but more
importantly, this is a milestone for the
Midwest Division and the company.
We’re going to utilize our cumulative
knowledge and experience to design and
construct a mine that is as close to
perfect as possible.” ▼
Crews have been excavating a pair of
tunnels at Fort Calhoun since March 2017.
photo by Phyllip Bowers
WHAT DOES
IT TAKE TO MOVE
UNDERGROUND?
The two tunnels leading to Fort
Calhoun’s underground will require
approximately:
■ 6.3 million pounds of
structural steel
■ 5 miles of rebar
■ 20,000 cubic yards of
concrete and grout
■ 12,000 roof bolts
■ The excavation of 175,000
cubic yards of rock and shale
10 January/February 2018 The Conveyor | www.martinmarietta.com