Aggregates Manager Digital Magazine
Issue link: http://read.dmtmag.com/i/145964
An automated unloading system allows asphalt millings unloading without the presence of any personnel. When a truck comes up, it triggers a sensor that starts up the system. This allows trucks to dump any time, day or night. Since quite a bit of road work is done at night during lighter traffic times, this comes in quite handy. "Some jobs allow 30-percent recycled asphalt in the mix," Nielson says. "We recycle asphalt in many of the mix designs. RAP has better rut-resistant properties than virgin oil mixes." At the primary plant, material is screened, sized, and sorted. Any oversize material is separated, sent to the crusher, and goes back through the primary plant. products, move things around," Nielson adds. A benching method is used in the 165-foot-deep pit. The dozer operators cut benches 10 feet out and 20 feet down. "We benched it for safety reasons, because we're right next to the railroad track," Nielson explains. "MSHA has given us high regards on our benches." Recycling asphalt Las Vegas Paving not only processes aggregate from the pit, it also recycles asphalt. Most of the asphalt being recycled is from the company's repaving jobs, such as the Interstate 15 project it was working on in 2012. Rotomilling machines go in and grind out about a mile or so of highway, and that section is repaved the same night. "We haul all the millings up here and dump them into our pit," Nielson says. "From there, we can feed them into the system and rework them. We bring them up the line, crush them down, and make them reusable material for the hot-mix plant." For safety reasons, a benching method is used in the 165-foot-deep pit. 16 Community encroachment Like most aggregate operations, Blue Diamond Pit was in the middle of nowhere when it began operation. "When this plant was built in the early '90s, there was nothing across the street but desert," Nielson says. "The houses were a mile or so away. Now, there are houses right across the street and a huge housing development is down the road." This encroachment has affected the operation in several ways. The road trucks use to come and go from the plant, which was once only used by Las Vegas Paving and its customers, is now being used by people in the surrounding community to get to and from their homes. Needless to say, the roadway gets busy at times. In addition to traffic issues, having homes so close to the operation brings the challenge of doing whatever is possible to control dust, noise, and other impacts. Being in the middle of a desert doesn't help with the dust management. The prevailing south wind can stir up dust anytime, anywhere, whether it comes from the operation or not. But Las Vegas Paving uses extraordinary means to control any potential dust emanating from its plant. "We've got 168 acres here, and we use our best efforts," Nielson says. "We've got a zero dust policy, but dust comes from the desert to the southwest of the plant." A full-time street sweeper runs constantly in and out of the plant entrance, cleaning the curbs and gutters of the main street to make sure there is no track out. The plant even moved its main Aggregates Manager August 2013 PlantProfile_AGRM0813.indd 16 7/17/13 2:05 PM