Aggregates Manager Digital Magazine
Issue link: https://read.dmtmag.com/i/107584
A new maintenance area was built near the pit so the wheel loaders and haul trucks don't have to drive as far for servicing. Two self-retractable lanyards were hung from the framework in each bay to help keep mechanics safe when working on large equipment. Photo courtesy of Cemex. A new wheel wash system, the first of two, was built at the quarry in 2012 to help with truck trackout. The system is referred to as the "yellow submarine" because of its color and size. The quarry property covers about 2,400 acres, with mining expected to reach depths of approximately 200 feet. The first 90 feet of the limestone deposit yields quality aggregate, while the next 30 to 40 feet is softer and grinds well, making it suitable for cement. Beneath that is another 70 to 80 feet of aggregate. "We're pretty much the economic engine for this area and for Texas, providing a lot of the aggregate for concrete and cement," Griffin says. "We supply about 3 million tons of cement rock to our cement plant every year. We have a clean stone market — some local clean stone and ready-mix suppliers — but our major clean stone market is down in Houston. We rail six trains per week to Houston. Houston is tied to energy, and the energy sector is doing very well. We also supply the oilfield business." The quarry supplies a lot of aggregate for the Eagle Ford Shale, an energy production area nearby in South Central Texas. That area is full of clay rather than rock, so a considerable amount of stone from the quarry is used for building roadways and drill rig pads. "We look at this market to be very strong, at least for the next 10 to 15 years," Griffin says. "Obviously, the big push for domestic oil isn't going to go away. Underneath the Eagle Ford Shale, there's the Pearsall Shale, which is just as lucrative. It's about 4,000 to 5,000 feet deeper, so they're targeting Eagle Ford 26 AGGREGATES MANAGER February 2013 first, then they'll go deeper to Pearsall." Griffin says the quarry processes about 35,000 tons a day through the primary crusher and is capable of processing more, if necessary. "We're permitted up to 4,500 tons per hour," he says. "We run two drills steady. We're running 220,000 to 250,000 tons per week out of here." Griffin credits his employees for the high production. "The guys make it happen," he says. "I have the best haul truck drivers; they're consistent and fast. When they run, they look after everybody. Loader operators are more efficient in turn. The primary crusher operator makes sure that the trucks keep dumping on a consistent basis. It comes down to the Teamwork aspect. They are very proud of what they do. They are striving for #1." Building a better mousetrap In addition to a hard-working crew, the operation also made capital investments to improve operations. For example, a new base plant was built in 2011. It provides commercial base for the oilfield roads and pads. The operation trades out between producing cement feed and commercial base, running cement feed twice a week. Between 600 and 700 trucks run out of the quarry every day, but Griffin says "the truck count has been as high as 1,000 per day. It's not unusual to have a line of trucks all the way up the hill and all the way down the hill." The central Texas area can be very dry and dusty, so all the conveyors are covered to help keep dust down. A new double wheel wash system was built at the quarry last year to help with truck trackout. The system is 40 feet long and holds 10,000 gallons of water. Each side pumps 500 gallons of water per minute, spraying it 10 feet into the air. "We designed it in conjunction with Holt Caterpillar," Griffin says. "Each system costs about $100,000. It has already been labeled 'the yellow submarine' because of its color and how much water it holds." A new maintenance area was built near the pit so the wheel loaders and haul trucks in the pit don't have to drive all the way back to the shop near the entrance for servicing. As it turns out, the new maintenance area helps the quarry in other ways, too. "It helps us in environmental compliance because we can do a better job of controlling everything," Griffin says. "The roof framework was put up totally for safety. Each bay has two self-retractable lanyards hanging from the roof structure to help keep the maintenance workers safe when working on large equipment." Embracing the community "The quarry was originally agricultural property," says Janet Krolczyk, director of environmental for the Texas and New Mexico region. It became a quarry