Room to work: a crushing plant site supervisor spells out ground rules for productive work flow.

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Ron Brocco of Independence Recycling, Valley View, Ohio, helps oversee two fleets of portable crushing plants that are deployed in two different parts of the country.

While one fleet operates in the Great Lakes region that the company calls home, another set of crushers is deployed throughout the Southeast as part of the Independence Recycling of Florida division.

Considerations and challenges can differ by region or can vary between two sites that are just 20 miles apart, according to Brocco. His job, in other words, is far from routine, and a healthy amount of planning and thinking must be addressed before a portable crushing plant is set up at any job site.

SPACE ... THE FIRST FRONTIER 

Before a portable crushing plant is towed onto a site, several important steps must be taken.

The planning process can start in the estimating phase, when Brocco or others at Independence work along with the customer to determine how much material will be generated that needs to be crushed, and which machine from the Independence fleet will be the best one for the job.

As the date draws near to bring a crusher onsite, a pre-visit (or a series of them) can help supervisors like Brocco determine where and how a crushing plant can be configured.

In the case of highway repaving projects, the choices can be limited. "Typically, with something like an interstate highway job, you're set up between the lanes in the middle of a median," notes Brocco.

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Some paving contractors may also lease land from a farmer with property that abuts a work area. This could in theory offer more space, but that space may not be ideal for crushing and stockpiling, notes Brocco.

"If they choose land that doesn't drain well, your loader might sink or spin its tires trying to move material," he remarks. You really can't stockpile this material in the middle of a farmers field."

Should the worst happen and soggy ground is encountered--Brocco jokingly refers to a peat bog--a technique his crews have developed is to use a wheel loader to take off the top of a pile and then later use an excavator to dig out the slabs or chunks that have sunk into the ground.

Securing enough space ensures that loaders and trucks have enough room to stage pre-crushed material as well as to later pick up finished material.

Long conveyors and the use of stackers can help Independence Recycling crews stay productive as well, notes Brocco. When finished material can be sent away from the crushing plant on radial conveyors and stackers, that allows the plant to stay in place and stay productive for a longer period of time.

Another alternative--and one that is common, according to Brocco--is to move the plant at least once during a decent-sized project. "When stockpiles become too large or the pile is getting awkward, it might be more sensible to move the plant," says Brocco. A thorough site survey before the job takes place will often allow Independence to calculate an "on-site mobilization charge" into the cost of the project.

A preferable alternative, Brocco notes, is when customers use material on site at roughly the same pace it is being crushed by the Independence crew. "If a contractor needs the material as quickly as we can crush it, it works for everybody," says Brocco. "About half the time it works out that way."

MATERIAL ISSUES

Another factor that affects several planning aspects involves the variety and types of materials to be processed and produced.

Should two or more types of materials be requested for on-site use by the contractor this can involve deploying additional screens and also require more room for segregated stockpiles.

On highway sites, producing a base course is the most common request. In Florida, where natural stone is harder to come by, the Independence crews are often producing No. 57 spec stone for use as aggregate in mixtures. "That means extra screens," states Brocco.

It also means extra stockpiles, which requires more space planning. "We'll stockpile what the customer wants--given the room," notes Brocco.

With its wide geographic range of operations both in the northern and southern United States, Independence also determines the type of aggregate contained in the material to be crushed before it selects the crusher it will send to a site.

"A lot of the areas we go to, we have a good idea as to the hardness or abrasiveness of the material--but it's always a good idea to do testing," says Brocco. Knowing the hardness or silica content of material can help the company calculate not only the rate of production, but also the wear on parts that will occur as the job plays out.

The task can be tricky, warns Brocco, who notes that on highway jobs covering a long stretch of road, two entirely different aggregate sources may have been used by two different contractors or suppliers on different sections when the road was built.

On demolition jobs the material generated presents an array of possible factors. "There's a lot of processing that needs to be done on demo jobs," says Brocco.

Independence will typically bring excavators with hydraulic processing attachments affixed to them to work through demolition rubble to separate steel from concrete before feeding material to an on-site crusher. (The cost of this is considered in the estimate.)

"There is the potential for nasty stuff to go through your [crusher] and cost you money" if such pre-processing is not done, says Brocco. He notes that a chunk of steel could bend a shaft or harm a rotor. "That could cost you $60,000 to $70,000," he remarks, as well as incurring downtime on the job.

"It's a lot more efficient to remove the heavy rebar," he continues. "We may over-prep in some cases, but it's still cost-effective in the long run."

NO NUISANCES

Setting up a crushing plant to be productive and efficient covers many of the bases that need to be addressed by a site supervisor.

Not to be lost in the process, however, is the need to set up a plant so it attracts as little unwanted attention (in the form of nuisance complaints) as possible.

Many of these concerns are addressed, by necessity, during the permitting process. But even a plant set up with the proper permits can still draw complaints, especially in residential areas.

Sometimes after a site visit, Brocco and the Independence crew may determine that moving a crushing plant "only about 50 feet, behind some trees, can help."

The foremost goal is to prevent complaints, but should they arise, responding is important, says Brocco. "We feel like we have an obligation to consider it as if it was our backyard that was nearby," he states.

When a job is completed, says Brocco, the goal of Independence Recycling is to clean up and even smooth out the land with a loader "to leave the site better than it was when we arrived."

Visit CDRecycler.com for more on five crushing companies in the Marketplaces section.

The author is editor in chief of Construction & Demolition Recycling and can be contacted at [e-mail].