The Texas Two-Step
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.
“We started construction on this plant in April 2006,” Ballard says, “and we kept our old plant running while we were building it.” The aggregates company continued to supply its customers with aggregate throughout every phase of the new plant’s construction.
The new primary plant was completed in June 2007 and was set to start running on June 29. But as Henry Wadsworth Longfellow once wrote, “Into each life a little rain must fall.” And it fell on the new plant on the night of June 28. The Marble Falls area received 19 inches of rain that night.
“We showed up the next morning to turn the plant on, and it was flooded,” Ballard says. “Nobody had any idea, because it happened through the night. I had berms, but I didn’t have berms to protect against 19 inches. That water just cut the berms out and came right into the pits.”
In the secondary, where construction was still ongoing, the damage was very bad. Construction equipment was still in use there and most of it was under water. A crane that was being used in the tunnel running beneath the surge piles was completely submerged; only the tip of the boom could be seen sticking out of the flood water. The crane was just one of many pieces of equipment lost to the flood that day.
“The whole town of Marble Falls, where the creeks and rivers run through it, was devastated,” Ballard adds. “There were boats in the streets and cars wrapped around poles and houses were destroyed. We had people who lived in those areas. We were in the process of trying to get pumps to clear the quarry, but we had people who had lost their homes and needed places to stay.”
Trying to take care of the quarry and help employees at the same time was quite a challenge, but everyone pulled together – employees and management alike – and help came from everywhere. The parent company, Zachry Corp., sent people from the corporate office in San Antonio to help clear the quarry and sent money, clothing, food, and water to aid employees who had lost everything in the flood. The company even moved one displaced employee and his family into an empty house on company property for a period of nearly five months until they could be relocated to another home. The company took care of its people, and the employees banded together to help each other and repair the plant.
“I got eight pumps in here from Houston and borrowed pumps from a company in San Antonio,” Ballard says. “I had about 16 pumps pumping water out of here. In three days, we had it pumped out, but what it left us with was an MCC [motor control center] house that was suspect now, and we had to go through it. All the idlers, and everything that was under water, had to be replaced. We expedited everything that we could and had everything going within three weeks.”
When the primary finally started up three weeks after the flood, the secondary still wasn’t finished, so the rock had to be hauled from the surge pile in the new primary plant to the old secondary plant in order to keep production going. The operation ran that way for five months until the secondary was completed in November 2007.
Once the secondary was up and running, the loadout was the next key item on the agenda. The contractor building the loadout brought in extra crews from Oklahoma and other places to expedite the construction. Finally, on Dec. 29, shortly after Christmas, Capitol Aggregates loaded its first train.
“I wouldn’t say everything was perfect,” Ballard says, “just ready to go. But we met a deadline. We made everything happen on time. Then there was a lot of tweaking – no plant that starts up is without its problems. There’s always some work to do yet, but we met our milestones.”
The company uses three 70-ton haul trucks and a large 15-1/2-yard front shovel to run the crushing operation in the primary pit. The shovel can load each haul truck in about 48 seconds – with just three scoops – which helps to speed the operation along.
When processing for itself, Capitol Aggregates sends the crushed Zone 2 ore on conveyors to the secondary plant. When processing for Chemical Lime, the belts are reversed so that the crushed Zone 1 ore is deposited into a pile for transport to the kiln.
“We mine the ore for Chemical Lime and put it in their stockpile,” Ballard says. “After we’re completed with their ore, we swap gates, change the plant, and start crushing overburden for us. So there’s two to three hours a day of crushing for Chemical Lime and the rest of it we’re crushing the overburden off the top. That’s where we get our product.”
Chemical Lime’s Zone 1 ore is brought up from the primary plant and placed in a surge pile located next to the plant office near the entrance. When the ore is needed, it is loaded onto a conveyor belt that carries it up and over the driveway to the vertical kiln on the other side.
Meanwhile, back in the secondary plant, the Zone 2 ore is being processed for aggregate use. “The secondary is down in a 40-foot hole for less of a visual impact,” Ballard says, “and that’s where we have our process plant feeding fractionated rock over a tunnel. That tunnel makes a blend of whatever product you want out of those piles. Then we send it up to a transfer station where we can put it on the ground or take it straight to the rail loadout system.”
The rail loadout system has a 250-ton storage silo fed by a conveyor at a rate of about 2,000 tons of rock per hour. Another conveyor then carries the aggregate from the silo to the railcars where it is loaded at a rate of about 2,700 tons per hour. “What we’re shooting for is loading 20 cars an hour,” Ballard says.
Everything is automated so that the gates open automatically and the conveyor loads the required tonnage into each car. Belt speed is adjustable and the direction is reversible so material can be fed out the back side, if desired. Bills are printed up and given to the customer from the rail loadout office, which sits high enough above the railcars to offer a bird’s-eye view to employees running the operation, allowing them to look down into each railcar as it is loaded.
Although most of the aggregate the company produces goes into asphalt and concrete, the new fractionated plant has opened up other markets for Capitol Aggregates. The company has more than doubled production since the new operation was built and can now make materials it wasn’t able to make before.
“We have six different sizes of rock out there that we can blend together,” Ballard says. “We can take somebody’s specs and fine-tune our rocks to meet that spec because we have all the different sizes to make it from. We can make anything from railroad ballast, which is big rock, to the finest of the hot-mix aggregates, and everything in between.”
Most of Capitol Aggregates’ rock goes to places in eastern and southern Texas that don’t have rock available. The Houston area gets rock from the company, as well as from many other sources. “You’ve got all the big players – the Martin Mariettas, the Vulcans – feeding that market,” Ballard says, “but we’ve cut our own niche into that market with some of their help. We’ve kind of partnered with Hanson Materials to sell them our rock because they couldn’t supply enough of their own. Houston needed more rock than was being supplied and we fit into that market.”
A bit of history
It all began with H.B. Zachry Co., a privately owned construction company that was founded by H.B. “Pat” Zachry in Laredo, Texas, on Aug. 23, 1924. The company got its start in highway construction. During World War II, it took on military construction projects such as runways, airports, and bases.
In 1957, the company began work on the runways at Bergstrom Air Force Base in Austin. In order to keep up with the demand for a large, steady supply of aggregates, Zachry decided to start his own aggregates company, so he formed Capitol Aggregates as an affiliate of H.B. Zachry Co.
“It started with one little operation – sand and gravel, ready-mix – and grew from there over the last 50 years,” says Capitol Aggregates Director of Technical Services Steve Eckert, P.E.
Capitol Aggregates now has eight different operations, one of which is a cement plant. Three operations are within an hour’s drive of Marble Falls – one a couple miles down the highway, one in Georgetown, and one located in Austin.
In the late 1990s, H.B. Zachry Co. became Zachry Construction Corp., which continued to perform heavy highway construction, commercial building projects, industrial process construction (including power plants), and industrial maintenance, as its predecessor did. And when logistically possible, the construction company purchased its supply of aggregates from Capitol Aggregates, its sister company.
“Zachry remains a customer, but is not a very big customer of ours, so to speak,” Eckert says. “But depending on where their jobs are, if we can get to them, we’ll try to sell them rock.”
There have been many changes for Capitol Aggregates in the last several years. The company sold the hot-mix asphalt business and a ready-mix business so that it could focus on aggregates and cement. Also, Capitol Aggregates’ parent company was reorganized into two corporations run by Pat Zachry’s grandsons. Capitol Aggregates – along with heavy and commercial building contractor Zachry Construction – is now part of Zachry Corp., under the leadership of David Zachry. But through all the changes, the dedication of the employees to each other and to the company has remained constant. Capitol Aggregates celebrated its 50th anniversary in 2007, but it doesn’t attribute that to trying to be like the big players. It succeeds by doing what it does best – breaking rock and taking care of its people.
Help for a Hometown Hero
Employees who work in aggregate quarries may be considered insignificant to some, but not to Capitol Aggregates and its parent company, Zachry Corp. When a plant employee’s son qualified to go to the 2008 Olympics last summer, the company, and the entire town of Marble Falls, rallied around the employee and his family.
Jesus Manzano has been an employee of Capitol Aggregates for nearly 20 years. He works at the Delta Quarry located just a couple miles down the highway from Marble Falls Quarry. His son, Leonel “Leo” Manzano grew up in Marble Falls, where he ran on the high school track team.
After graduating from high school, Leo went on to attend the University of Texas in Austin, where he runs on the college track team. The citizens of Marble Falls have followed Leo’s accomplishments since high school, as has his father’s company. So when Leo became the first University of Texas 1,500-meter runner to make an Olympic team, it made headline news. A large banner went up across F.M. 1431 near the Highway 281 intersection that read, “Welcome to Marble Falls, home of Leonel Manzano.” Signs of support hung from shops and buildings, and billboards wished him luck.
When supervisors at his father’s plant heard the news, they sent the information up the company chain where it finally made its way to David Zachry, the owner and president of Zachry Corp. Zachry felt that, if Jesus Manzano’s son was good enough to make the Olympic Team, the family should go watch him compete. So the corporation went to work to make that happen for the Manzano family.
Zachry Corp. bought round-trip airline tickets to Beijing, China, for the entire family. Then, the company provided the family with a nice place to stay by offering them the use of corporate housing it owned in Beijing. The corporation also assisted the family with obtaining all the necessary documentation such as passports – all at company expense.
The Marble Falls community held fundraising events and presented the family with $10,000 to help pay for meals and other travel expenses while in China. The Manzano family said that whatever money was leftover when they returned would be donated to the Highland Lakes Track and Field Club. Before Leo left for Beijing, the town held a festival in his honor as a send off.
Leo made it through the first heat in Beijing, and qualified to move on to the second, but, unfortunately, didn’t make it past the second heat to the finals. He did, however, represent his country very well, and made his hometown, Capitol Aggregates, and Zachry Corp. very proud.
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