The impact crusher belonging to Independence Excavating is at the center of some high-flying activity – literally.
Parked on a former runway at Cleveland Hopkins International Airport, the tracked crusher is adjacent to an active runway where planes continuously take off and touch down.
As a 450C LC hydraulic excavator feeds material to the impactor, a United aircraft, perhaps bound for New York or Chicago, accelerates on the ground and disappears from view behind a series of stockpiles. The plane reappears in the air just above a stacking conveyor after a few moments, leaving this young crushing job and the airport surrounding it behind.
Next, a massive Spirit plane appears from the sky, touching down 100 yd. or so away from the crusher before taxiing around the jobsite and making its final stop at the gate. Minutes later, a multicolored Southwest plane whizzes by and lifts off to some faraway place.
The airline traffic is nonstop. It’s part of Independence Excavating’s job here at Cleveland Hopkins, which plans to eventually install drainage pipes within the old runway to manage stormwater runoff.
Until then, Independence Excavating continues to tear up the old runway and crush the clean concrete into a couple of products.
“Right now we’re making 57s and fines,” says Dave Roberts, plant operator at Independence Excavating, when visited on a sunny midsummer morning. “After this, we’re going to be making P-219. It’s like a base – basically like a 304. It’ll be a 2-in.-minus base.”
Managing dust
While Independence Excavating is particularly active around Cleveland, the company also takes on a number of jobs throughout the United States. With offices in Independence, Ohio, Pittsburgh, Chantilly, Virginia, and Aurora, Colorado, the company performs work in site development, demolition, heavy industrial applications, environmental remediation, concrete construction, aggregate crushing and recycling.
In recent years, Independence Excavating has played a role in some of the largest and most challenging building projects nationwide. The company performed engineering feats to redirect a creek beneath an airport runway in Cleveland, and it constructed a NASA testing facility that currently neighbors the Cleveland airport.
The company’s crews also successfully demolished major landmarks, including the Citrus Bowl in Orlando, Florida, and they overcame inclement weather and aggressive scheduling to extend runways in Martinsburg, West Virginia, for one of the largest military aircraft in the world.
Jobs like these, as all contractors find, have some unique components. Independence Excavating’s current crushing job at the Cleveland airport, as expected, has some of those.
One area of the job the company constantly monitors is dust. Active airports, after all, have strict requirements on dust.
“We’ve got a water truck there, and if it gets 90 degrees we’ll have it come and spray the pile,” says Roberts, noting that the truck will apply between 700 and 1,000 gallons per spray. “We have two brackets on top of the crusher, and I can turn them up or down and spray water right into the hopper. It keeps the dust down and works pretty well.”
Some crushing jobs produce more dust when starting up or shutting down, Roberts adds. Independence Excavating experiences some of this at the airport, but the crew is cognizant of it and takes the necessary steps to suppress any dust produced.
“If there are high winds that blow dust around, I’ll have them put a little more water down,” Roberts says.
Of course, with 57s, too much applied water can lead to fines that stick.
“You have to find the happy medium on how much water to give it,” Roberts says.
Roberts also keeps crusher wear in mind when spraying. Blow bars, for example, can wear faster as water is applied, he says.
Key equipment
As of late July, Roberts estimates Independence Excavating had crushed 72,000 tons of concrete at the airport. Stockpiled 57s represent about 42,000 tons of the production, which began in late spring.
To process material, the company leans on a couple of uniquely crafted processing units, including an HX500 impactor that has a Hazemag crusher within it.
“We like to use Hazemag crushers,” Roberts says. “They’re a better impactor than most. It’s a Powerscreen, but they put a Hazemag on it. It’s beefier, stronger.”
The tracked screening plant operating in tandem with the crusher is built similarly. It has a Powerscreen body yet possesses a triple-deck Cedarapids screen deck on it.
“It’s a good screen,” Roberts says.
On this job, Independence Excavating typically crushes for a few hours before having to move the crusher.
“I get about 2 1/2 to three hours with a windrow this size,” Roberts says. “We’ll shut down, and then I move everything back. It takes about a half hour with my guy on the skid steer. Then we go back to crushing again. Each pile represents a move.”
Also essential to the job are Independence Excavating’s stacking conveyors. The company is utilizing two from Telestack, as well as one from Edge Innovate.
“We buy a lot of equipment from AggCorp,” says Roberts, referring to the company’s Cleveland-area dealer. “This is all Independence Excavating equipment, although this is the only track impactor we have. We have two track jaws, a couple of track screens and a bunch of track conveyors. They’re nice on jobs like this where you move.”
One advantage of crushing an airport runway is that the concrete is extremely clean, Roberts adds.
“There’s a little bit of wire in it, but we’re making a nice product,” he says. “Usually when a guy is loading [on other jobs] there is dirt in it – you need a little bit of fines. But this has probably been some of the best concrete I’ve crushed.”
Any tramp metal that makes its way into the crusher is easy to manage because of the crusher’s design, Roberts adds.
“As far as the impactor, all of this stuff can go through that,” he says. “The aprons are all on hydraulic relief. If you get something hard in there, the aprons will open up – you have your top and bottom apron – and it will let that stuff out. Your magnet kicks it right out to a pile. It’s almost like a tramp relief on a cone or a jaw, but your aprons will open themselves up.
“Then they have a proximity switch,” Roberts adds. “If the crusher detects that it’s opened it up, it will close them down shut. Or, if I get a piece stuck in there, I have a remote. I can manually do it with a remote, or walk up to the crusher and open it up if something gets stuck.”
What’s next
The job at Cleveland Hopkins International Airport is really just beginning. Independence Excavating expects to crush on site this year until about November, when salting crews arrive and add to the airport’s traffic.
“They don’t want anybody in the way,” Roberts says.
Until then, Independence Excavating has plenty of concrete left to crush between the road it’s currently on and other taxiways. Plus, there will be an opportunity to crush more runway at Cleveland Hopkins in a separate bid.
“We’re only going 18 in. [down] now,” Roberts says. “We want to keep good concrete for 57s. We will be going down 4 ft. because we’re going to go after everything when we get our P-219 and 304, making our base.”
Also, on a high-security site like this, Independence Excavating must make sure all employees stay within the permitted area.
“It’s a little more challenging to keep everyone in the right area,” Roberts says. “If you walk over there, you may never be allowed to walk on site again. There are certain places you can and cannot be. We all went through a class, and it’s my job to keep them there.”
Visit the job
Independence Excavating’s Dave Roberts takes PP&E inside the crushing job at Cleveland Hopkins International Airport in an exclusive video.