Working areas in and around excavation are constantly inspected for falling or loose materials sloughing from the banks and walls, according to Smith. Stockpiles are kept pushed down from the top to avoid undercuts in the material.

“Our best safety tool against becoming involved with any kind of ground control issue is inspection and avoidance,” Smith says. “We back into parking spots so that we’re looking forward when we’re ready to leave. All our production equipment and yard loaders have CB radios, as do our control rooms, so that communication is not a problem. We employ bucket scales on all our end loaders, even the pit loader, to ensure that we don’t overload equipment. Our production equipment is also equipped with back-up cameras for additional safety.”

From the beginning

“Southern Ready Mix built this plant in approximately 1977 and began operating this crushing facility then,” Smith says. “The cement plant next door was seeking high-calcium limestone for the manufacture of cement and created quite a bit of spoil from those activities, which was a fantastic aggregate. So, this plant worked in conjunction with the cement plant crushing the muck that was otherwise unsuitable for cement production.”

Lafarge acquired the operation in roughly 2004, Smith says. The company acquired the cement plant as well, and both plants continued to work together just as they had in the beginning. Modifications and improvements to the cement plant have made it one of Lafarge’s premier cement plants in the United States.

“In some respects, it was an environmentally friendly, responsible endeavor because we were crushing the material that otherwise would have been discarded, thrown away, or backfilled,” Smith says. “We were actually using that material to supply local markets with excellent construction aggregate.”

That continued until about 2008, when Lafarge Cement and another construction materials company entered into an arrangement to do some mining together to secure reserves for both operations. “At that time, we began operating the quarry like any other operation,” Smith says. “We were actively mining, drilling, and blasting in one of the pits that had been in existence from the original cement company. Now we’re going after the reserves below the high calcium horizon left behind by the cement operation. It’s a significant change from having muck material brought right up to the crusher and dumped, to actively going out and drilling and blasting and hauling the material to a crusher just like in any other quarry.”

It takes teamwork

Calera Quarry has a small workforce of 13 employees ranging in age from 20 to nearly 60 years old, yet they manage to produce around 1 million tons of material per year, plus or minus. “I have a team member here who has 30 years of service at this property and another with 24 years of service,” he says. “I have several who have been here in the teens of years. But we do have some young guys that have filtered in as others retired or moved on.”

Almost everything at the plant, with the exception of the secondary crusher, the tertiary crusher and screen, and a belt or two is the same as it was in 1977 when the plant was built. It is still a manual plant, requiring an attendant at each stage of production.

The older equipment still performs well, and Smith credits this to the plant’s maintenance program. “We have a rigorous maintenance program that includes inspections, planning, performance, and follow through,” Smith says. “We do very specific inspections at specific intervals as determined by our maintenance program. From those inspections, we’ll plan ahead of time for what we need to do. Then, when we take the time to do those things, we do them efficiently. It’s a continuous cycle of pro-active maintenance activities. Obviously, things do still break, so we still have the reactive component in our maintenance program, and we always will, but we like to feel that the reactive component is much less than it would be without pro-active maintenance.”

Maintenance times depend on the seasons of the year. The quarry maintains a minimum inventory, so maintenance is matched with the production schedule, which is in tune with the demands of the marketplace. At times, this requires a split shift for the maintenance team.

“Our production people come in the morning and do pre-shift inspections, check their equipment, and we produce,” Smith says. “Then we do our post-inspection in the afternoon. The evening shift [maintenance team] knows what they have in front of them. They take care of the details, and we come in the next morning ready to go.”

Surviving the lean market

The Norfolk Southern Railroad has helped Calera Quarry maintain market share through the lean economy. “We have actually fared well because we have access to long-range markets through the rail,” Smith says. “We’ve been very fortunate. In fact, my team is still working five days a week in excess of 10 hours a day. Part of that is maintenance, but most of it is meeting production demands for our customer and contractor base.”