Topcon GNSS Streamlines Construction
Technology provides productivity to burn at expanding waste-to-energy facility
Few companies in the U.S. do waste-to-energy as well as Covanta. The Morristown, N.J.-based provider of sustainable waste and energy solutions operates more than 40 facilities domestically, as well as locations in Canada, Europe and China, each committed to turning a once problematic material — residential and commercial solid waste — into a valuable source of energy.
As part of its ongoing commitment to continually grow and improve, Covanta has been expanding its Niagara Falls, N.Y. location, a move that involves construction of a new rail-to-truck intermodal facility and gas boiler. When Pinto Construction Services (PCS) won the bid to make the intermodal project happen, company leaders saw a huge opportunity to draw upon the GNSS solutions that had proven so popular in past projects. That effort has resulted in the Buffalo, N.Y. contractor meeting stringent demands, working through challenging environmental conditions, and seeing jobsite efficiencies skyrocket.
Driven by increasing global energy demands and traditional energy sources that are either dwindling or recognized as being environmentally harmful, alternative sources to meet those demands have come to the forefront. “Energy from Waste” technology, which involves processing of municipal solid waste into heat, electricity and pellets generally known as refuse-derived fuel, has proven beneficial both for its potential and its ability to divert waste from landfills.
At Covanta’s Niagara Falls facility, the expansion is allowing improvement on both fronts. The new boiler will increase the efficiency of incinerating more than 2,250 tons of municipal solid waste per day, while the rail-to-truck facility will serve as the focal point for unloading waste shipped in from metropolitan New York City — an area for which landfill disposal is all but a moot point.
The upgrade/expansion has been in the works for some time, reports Greg Maziarz, PCS’s survey manager and project engineer.
“In late 2012, we started Phase 1 of the project, which was the realignment of one of the main rail lines into the plant,” he says. “This was on an adjacent site that was very environmentally sensitive; all sorts of material had previously been buried there. We had to install the new track line, but anything we uncovered as a part of that process had to be surveyed and mapped.
“Because the site was flat and wide open,” says Maziarz, “we saw it as a great opportunity for a GNSS-guided machine control system, as well as multiple receivers on the site. We brought in equipment and started digging and grading. We actually used a GNSS-equipped dozer to mark out boundaries — a real plus since we would never have been able to get any wooden lath into the frozen ground.”
That effort was followed in the fall of 2014 by Phase 2, which was the remediation of a larger parcel next to the first. It was similar in nature as well — locating any structures in the ground, removing them or filling them with concrete, and so on.
“During that remediation phase, we took this whole site down an average of two feet, and removed any waste and slag we encountered,” says Steve Beahen, PCS’s project superintendent. “There was 11,000 feet of old track that was totally buried beneath brush and weeds. We grubbed it all, demo’d all the tracks and ties, cut the whole site down, hauled off 30,000 tons of contaminated soil and material (in addition to the 20,000 tons removed in Phase 1), and brought in about 50,000 tons of new 2-inch runner crush.
“We didn’t start that phase until September, yet we were still out of here by Christmas,” Beahen says. “It was quite an operation. We got a late start, but more than made up for it with incorporating GNSS-guided machines and equipment.”
Using GNSS technology at the Covanta site paid dividends in other regards as well, Maziarz says. “We were compensated on volume, so using either the bucket of the excavator or a rover, we would position anything we dug up,” he says. “Using Topcon Pocket 3D, we were making informative maps in real time, which we would then send off to the owner with supporting images. They had proof of our volumes, allowing us to backfill and move on. It was really an efficient system.”
With the preliminary phases completed, PCS moved on to the major component of the project: capping the site with stone, installing drainage throughout, laying down five additional rail lines of nearly 3,000 feet each, creating massive pads for the unloading effort, and erection of a new thawing structure.
One of the most complex elements of the project is not even visible, Maziarz says.
“Even though the site’s inbound containers will be completely sealed and there is virtually no risk of spillage, Covanta has gone to great lengths to make certain that all stormwater is collected and sent to a monitoring station, where it will be verified as being safe before it exits to the city sewers,” he says. “As a result, there are nearly five-and-a-half miles of piping running beneath the concrete pads. We built the model for all the work being done including that massive web of storm sewer, loaded that design into the excavators we have onsite running Topcon X-63 machine control, and they just went to work doing the 4-inch under drain.”
Because each operator has the digital model loaded in their machine control software, Maziarz says, if they are working on an area and something holds up their progress, they can easily move to another part of the site, work there and then come back to the original point to resume work. “And almost all staking has been eliminated. Even though the expansion site is 15 acres, pounding and working around stakes would have been a nightmare given the amount of activity on site.”
Key GNSS-equipped machines used by PCS at the Covanta site included a John Deere 750J dozer with Topcon 3D-MC2, as well as Komatsu PC400 and PC138 excavators and a Doosan DX225 excavator each running Topcon X-63 systems.
“There were so many facets of this job in which our decision to go with GNSS was proven out,” Beahen says. “We used the John Deere 750 to grade the entire site, including the track areas in which tolerances had to be within a half-inch. The accuracies were so solid, in fact, that the concrete crew came in right behind us, settheir forms for the pad and put down rebar without needing any additional grade work done. Normally, that would require a separate fine-grade operation with a lot of handwork and smaller equipment. That was all eliminated because the dozer with a GNSS machine control system gets things so close the first time.”
Efficiencies were also enhanced in an area in which the massive concrete pad butts up against a blacktop area. PCS built the design model to indicate that transition and, by doing so, was able to cut subgrade for both areas at the same time and put the stone down in the asphalt section. Once the concrete was poured, crews simply stripped those forms and made a single pass through the adjacent section before putting the blacktop down. The combination of grade stake elimination, improved efficiencies and ability to work in different areas has dramatically impacted production, Maziarz says.
“It’s hard to quantify how much faster we’ve been out here because of GNSS, but I don’t think it’s a stretch to say production has at least tripled over what it once was,” he says. “There were times when Jim Panepinto, my boss, would come out to the site and just be blown away by how far along we were. The Topcon systems have improved performance in almost every area of the job, from grading to trenching to excavation.”
As one of Western New York’s most indemand general contractors, PCS prides itself on its ability to quickly respond to its customers’ needs. By way of a final example, that strength, enhanced by its GNSS capability, was evident in the construction of a settlement pond on the Covanta site. According to Beahen, a midstream change which could have disrupted schedules was easily handled.
“The pond was originally designed to be constructed using topsoil,” he says. “But, after we excavated, the engineers decided to switch to a fabric and riprap construction instead. Obviously, riprap is a bit harder to handle and definitely more of a challenge to grade. But Greg built the model for it and Dwayne Seiler, our operator, using the GNSS-equipped Doosan excavator and a grading bucket, did it in just a couple of days. That just really sums up how impactful the technology has been for us out here.”
When complete, the new $30-million Covanta Niagara Rail-to-Truck Intermodal Facility will allow the company to more efficiently deliver up to a half-million tons of waste per year by train, reducing the amount of truck traffic on area roads and into the facility by 30 to 50 percent.