Aggregates Manager Digital Magazine
Issue link: http://read.dmtmag.com/i/301563
OPERATIONS ILLUSTRATED AGGREGATES MANAGER Voices of Experience Bill Page Jim Tweedy ▼ ▼ "O ne thing I think about when constructing a berm is what type of material to use," says Bill Page, project manager at Duff Quarry in Huntsville, Ohio. "If you build a berm with too much fines in it or cover it with fines, within a year or so you're looking at big weeds growing up alongside your roadway or project. We generally try to choose a material that will slow or stop a machine, but won't support agriculture. You want it to look good five years aer it is built and, hopefully, still be in place. If you use a material that's stable, you don't have to do much to maintain it. You just need to keep an eye on it. If you use a material that's not very stable, rain and time will cause the berm to sele, and you may have to touch it up more oen. If you use a larger, coarse aggregate, it will still be there. It's not going to change much." At Duff Quarry, wheel loader operators generally take care of building and maintaining the berms. ey are constantly on the move in the quarry loading trucks, so they can easily transport a bucket of aggregate to repair a berm. Haul trucks are sometimes necessary to transport large amounts of material, if a berm is being constructed or a repair is extensive. Prior to constructing a berm, it is important for the plant manager or person in charge to do a site survey. "He needs to look at the con- dition of the area where the berm will be constructed," Page says. "Is it solid? Is there a weakness? Are there cracks in the wall? Every area is different. He needs to work with the loader operator building the berm or the haul truck driver bringing in the material to make sure it's placed on solid ground." e sale of material continues at Duff Quarry during the winter months, but production shuts down due to the harsh weather. Prior to starting back up in the spring, every berm is inspected to determine where repairs should be made. Some repairs may be needed on perimeter and roadway berms, but, according to Page, some of the biggest areas of concern are the stockpile berms. Material is drawn from the stockpiles during the winter months, which can undercut the berms. "ere may have been a berm to start with, but it may have dissolved or rolled over the top as the material was extracted below," Page explains. "Once activity gets underway at the quarry, we look for those situations and make sure those berms are put back in place." A s the plant superintendent at CalPortland's Pioneer Aggregates Plant in DuPont, Wash., Jim Tweedy says berms are an important part of the planning process. "When considering where to place a roadway, we make sure to design it wide enough to accom- modate the stable base of a well-constructed berm," he says. "We need at least a traffic-width road plus room for a berm. At a minimum, the base of the berm will be three times as wide as it is high." MSHA requires that berms be mid-axle high of the largest piece of equipment operating in the area, but Tweedy looks at that as a mini- mum requirement. "If you aim at just mid-axle height of your largest equipment, within a month, the berm will be a bit lower than that," he explains. "Over a period of time, that berm will sele due to rain and freeze-thaw, so it needs to be prey substantial to begin with. We try to build that berm higher than what it needs to be, initially, and then monitor its height." It isn't always the berm that seles, sometimes the roadway elevation changes due to material spillage. "We see that a lot at feeders where material spills as the equipment pulls away," Tweedy says. "Over time, that will increase the height of a ramp or roadway, and, prey soon, the berm is no longer high enough. So we cut it back down with a grader or wheel loader." Berm maintenance is ongoing at the quarry. It's part of the work area exam for equipment operators. ey are expected to monitor berms on a daily basis and either repair them or report the conditions to their supervisor. Because the Northwest receives so much precipitation, drainage areas are designed into the berm to allow water to pass through. ese may be small breaks in the berm or an area filled with larger material. Not all berms are built out of aggregate, however. "We took a jersey barrier form and modified it to be more than mid-axle high on the largest piece of equipment feeding batch plants and ramps where loaders are feeding hoppers," Tweedy says. "We use retained concrete from our ready-mix plants to build them. e new barriers don't take up nearly as much room, yet provide stability and strength, and they can be pinned together to form a longer barrier. "We are also using some large concrete and steel pilings for berms," Tweedy adds. "ey are substantial in size, and allow water to drain freely beneath. Each end of the piling is buried in a pile of aggregate for stability. ese also make good backstops at dump sites."