Aggregates Manager Digital Magazine
Issue link: http://read.dmtmag.com/i/891178
by Kerry Clines | Senior Editor PLANT PROFILE 10 AGGREGATES MANAGER / November 2017 O ff the beaten path in southern Iowa, Martin Marietta's New Harvey Sand plant is dredging up sand and gravel in the middle of farming country southeast of Des Moines. In fact, the land being mined is the property of a farmer who is leasing it to the company. After mining is complete, the top soil will be backfi lled into the mined-out areasto become farmland again, but there will be a nice, big lake to boot. Martin Marietta purchased the dredging operation from Kaiser Corp. in 1997. The property consists of 350 acres bordered by the Des Moines River to the north and east and Highway 92 to the south. A new scale house/offi ce building was just constructed in 2017. "We started construction of a new building in January/February this year," says Tim Chambers, plant manager for New Harvey Sand and four other opera- tions in and around the Des Moines area. "They ran into problems with frost, so they couldn't put in the footings. Then we had the spring rains that delayed construction. It has been a challenge," he explains, adding that they worked out of a small job trailer until the new building was fi nished. Dredging up profi ts The sand and gravel in the area was deposited by the Des Moines River over a long period of time. Before any mining can begin, the area must be cleared of overburden. A stripping crew comes in and strips off the overburden, which varies in depth depending on location. "Our core drills let them know how much to take off in each area," Chambers explains. "Where they're working now, one end has 2 feet of overburden and the other has 8 feet. Some pits have 18 to 20 feet of overburden." Once the sand is exposed, water begins seeping in from the river and forms a pond. The dredge is then moved into the pond and mining can begin. "We have a chain dredge that looks like a chain saw with a vacuum cleaner hooked to it," Chambers says. "The big blade rotates and knocks the material loose so it's not packed tight. Then, the big nozzle sucks it up, and sends it through a 12-inch poly pipeline. A booster pump pushes it the rest of the way through the pipeline to the process- ing plant." When the material reaches the processing plant, it goes up 40 feet to the top of the plant and is fed through a Mining Heartland Heartland Heartland in the New Harvey Sand is stacking up safety awards while dredging up profi ts in the Heartland.