Published on July 1st, 2014 | by UC&D Magazine0
Earth Mover, July 2014
Gravel pits are notoriously dirty places.
Ask Carl Clyde, who has been working at Geneva Rock’s Point-of-the-Mountain pit for more than three decades, and is keenly aware of the stereotypes that go with the aggregate mining business.
“This is inherently a dirtier business than most,” said Clyde, Vice President of Gravel and Asphalt. “I know communities don’t like living close to gravel operations. But this location has a unique source of rock that you can’t find in the west desert. Actually, very few places in Utah have this kind of quartzite, which is ‘pre-split’ by natural seismic forces. This aggregate is almost perfect.”
As the Point-of-the-Mountain site is gradually dug out to the east, the location of the material becomes farther and farther away from site batch plants. In an effort to reduce equipment wear-and-tear, cut back on fuel consumption, and mitigate particulate matter in the air, Geneva has invested $11 million into a new high-tech overland conveyor system that can move up to 3,000 tons of material per hour and is unique to Utah’s aggregate market.
One major reason is that the gravity- fed system (the system’s steepest point is an 18.5% grade) will generate electricity and ultimately be able to power much of the 50-acre-plus POM site (east side of I-15), Clyde said.
“In doing our investigation within the sand and gravel business on the construction side, we’re not sure there is anything like this in Utah – a downhill conveyor system generating electricity,” said Clyde. “The final phase of this project will be to get power contained and interconnected on our property that will distribute power to all facilities.”
New equipment includes three overland conveyors at 2,500, 1,500 and 800 ft,, respectively, ranging from 36 in. to 60 in. in width., along with another 100 ft. conveyor, a 150 ft. radial stacking conveyor, and two 100 ft. tunnel feeders. Geneva would have needed to add nine haul trucks to its fleet to get similar production.
“We’ve been working on a way to get material down the mountain for the past 3-4 years,” said Mark Oviatt, President of Salt Lake-based Kimball Equipment, which supplied the Superior Industries conveyor system. “Not many firms have put in the expense of a long downhill conveyor. It’s a considerable investment on their part and they did it right. It’s hard for firms to look that far forward and see the payoff.”
Clyde believes the $11 million investment will pay for itself in approximately two years. Factors besides fuel savings (yet to be determined) include cost analyses of labor and equipment, including depreciation values, parts, maintenance, etc. Other benefits include having safer operations and being good environmental stewards, both of which offer immeasurable returns.
“Safety was an important consideration. As the mountain gets higher, you have to address the issue of how to safely bring the aggregate down,” said Clyde, adding that he’s asked quite often by people he encounters how long the pit can continue being mined for aggregate. Clyde wouldn’t speculate, saying it will be tied to economic conditions and the state’s future construction needs.
“How long it lasts depends on the economy,” he said. “In the early 2000’s we had that phenomenal growth for 6-7 years, which turned out to be artificial. If we could replicate that kind of growth it wouldn’t last very long.”
Overland Conveyor Project
Cost: $11 M
Equipment: Kimball Equipment Co./ Fabtec/Simplicity: Grizzly Feeder
(62”W x 28’L) Kimball Equipment Co./ Superior Industries: Overland conveyor
(60” W x 2500’ L, 3,000 tons per hour), conveyor (60” W x 100’ L, 3,000 tons per hour),
radial stacking conveyor (60” W x 150’ L, 3,000 tons per hour),
tunnel feeder (100’ long, 1,800 tons per hour), tunnel feeder (100’ long, 1,200 tons per hour)
Goodfellow Corp./ICC/Goodman: Overland conveyor (36” W x 800’ L, 1,200 tons per hour),
tunnel feeder (140’ long, 1,800 tons per hour), overland conveyor (48” W x 1,500’ L, 1.800 tons per hour)
Subs: Ram Enterprises
(some conveyor belt install; structural concrete); CVE (electrical)
Estimated fuel savings: TBD
Estimated ROI: 2 Years
Start/Completion: Dec. 2013/May 2014