A model of perfect cooperation, Marble Falls Quarry provides two different products for two different companies, all at one location.

by Kerry Clines, Senior Editor

For those who don’t know, the Texas Two-Step is a country western dance in which two dancers move together across the dance floor in perfect unison. Each dancer depends on the other to move in the same direction at the same time, sometimes forward and sometimes backward, and to keep in step along the way. It takes cooperation.

That’s the kind of cooperation that can be found at Marble Falls Quarry, an operation that sprawls across the central-Texas hill country just north of the small town of Marble Falls. The quarry is run by Capitol Aggregates, a Texas-based company owned by Zachry Corp.

At first glance, Marble Falls Quarry appears to be a typical crushed stone operation – rock trucks come and go, rail cars are loaded with crushed rock, conveyors run here and there looking like a roller coaster ride at an amusement park – but upon closer inspection, there is something a bit different about the operation. Just inside the entrance to the plant, right across the driveway from the plant office, looms a huge Chemical Lime kiln.

How it all began

Chemical Lime actually owns the reserves at Marble Falls Quarry and has been mining chemical-grade dolomite (Zone 1) for years. The ore that the company needs for its kiln is on top of the ground in the south section of the quarry, so it can be mined easily. However, in the north section of the quarry, it’s a different story. The desirable chemical-grade dolomite is covered by a dolomite the company doesn’t want. As a result, the company realized there were only 15 to 20 years of exposed ore left. Something needed to be done to ensure that the buried ore could be mined into the future.

So Chemical Lime contracted with Capitol Aggregates to remove the overburden of unwanted dolomite layered on top of the Zone 1 ore. “They hired us to come in here and take what they call Zone 2 ore off the top of their Zone 1,” says Brett Ballard, plant manager for Capitol Aggregates. “So when they mine out of what’s exposed to the south, we’ve exposed another 30 years of ore for them. That’s the purpose of us being here.”

As it turned out, the overburden was very desirable to the aggregates company, making the contract a win-win situation for both Chemical Lime and Capitol Aggregates. “It just so happens that the rock they want removed is an excellent quality for the aggregate business,” Ballard says. “It’s a high-quality and dense rock with low silica that’s great for ready-mix and the hot-mix industry.”

Building the plant

Once an agreement was reached for Capitol Aggregates to start removing the overburden rock for Chemical Lime, a new, modernized plant had to be designed and constructed that would increase the capacity of the operation. About three years of discussion went into the planning and design of the new plant, which needed to be able to process material for both Capitol Aggregates and Chemical Lime. Reversible conveyors and chute work had to be incorporated into the design. Crisp Industries worked with the companies, completed the final design, and then built and set up the new plant.