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Building a convincing case for the zero-sort alternative


The era of multiple recycling bins for cans and paper could soon fade away, replaced by a "zero sort" alternative that appears to be gaining momentum.

And that's exactly how things will play out if John Casella, chairman and chief executive officer of Rutland, Vt.-based waste hauler and processor Casella Waste Systems Inc., has his way. His company runs 38 materials recovery facilities (MRFs), of which six are already equipped to handle "zero sort" recyclables that reach MRFs from curbside pickups. The East Coast trash processor eventually expects to convert another 21 of its 38 facilities to the single-stream approach.

Rolling mills and paper mills don't need to worry about substandard scrap quality, at least if they're buying from his company, Casella said. "The notion that the quality of single stream is not as good as dual stream is not correct. The differentiating factor between a good single-stream facility vs. something that someone is calling single stream is whether they really have invested in technology to create a high-quality product. We're seeing retrofits of anywhere from $3.5 million to $5 million on an existing facility; the higher figure is if you've got to do alterations for the building."

Optical sorting and sophisticated particle screens have advanced greatly over the past few years, Casella said. Instead of three plastic output streams, for instance, there are now eight. Broken glass is the most worrisome contaminant, but even that can be removed.

With no subcategories of recyclables at the home or business generating the material, "you can right size the container. Instead of an 18-gallon bin you put in a 65-gallon or 95-gallon toter. You don't have the recyclables going into the trash by midweek because there's no room in the recycling bin," he said. "You bring up the participation (by households) and you bring up the yield in pounds per home with that program."

One of Casella's MRFs processes recyclables from Cambridge, Mass., which faces a decision on whether to go to single-stream recycling when its current arrangements expire in mid-2010. The minutes of the city's recycling advisory committee meeting, posted on the Web, provide insights into the decision process. One issue is that "revenue payments for recycling will decrease because of higher sorting costs (with single stream). But if trash tons decrease (shifting instead into the recycling stream), the overall program will be a financial success," said one guest from Boston's recycling bureaucracy.

The system might not fit the bill for all applications, but with the right technology a true single-stream operation can make the grade for the vast majority.

Waste Management Inc., the Houston-based giant of the trash industry, began moving its MRFs toward single stream in 2000.

"It doesn't make sense quite yet everywhere, but it's sure making sense in a lot of places," said Lynn Morgan, who represents Waste Management in Wisconsin, where the company recently reconfigured its Milwaukee-area MRF. "The technology has reached the point where the task of sorting, which used to belong to the waste generator, is being transferred to the processing facility. Waste Management has mapped out a plan to triple the tonnage that it recycles. One of the ways to get there is by implementing single stream."

Other parts of the company's strategy include drop-off sites for electronics and providing mail-in envelopes for compact fluorescent light bulbs, which contain mercury.

The actual decision to switch to single stream generally rests with municipalities or counties that carry out, or at least oversee, the collection arrangements. The company's Waste Management Recycle America unit tries to nudge communities in that direction.

"Typically we're seeing gains in household recycling of 20 to 30 percent," Morgan said, adding that it's much easier to get businesses to recycle systematically with single stream, particularly if a company's work force has a high turnover rate. "It's difficult to train and coach people on more-complex sorting systems. Single stream simplifies what employees need to learn and what the janitorial staff needs to segregate. You need just one large container at the loading dock."

Denver phased in single-stream recycling during 2005 and 2006. It was the region's pioneer in such a switch, so to get a sense of how the change might play out it sent officials to San Francisco and to Phoenix.

Charlotte Pitt, Denver's recycling program manager, said there were four main reasons for the switch "Getting our drivers out of the business of lifting recycling bins, operating more efficiently, providing a container that made it easy for us to participate and having the ability to add more materials. We're very confident we made the right choice. We've got more people to recycle more material. We're not seeing injuries on our crews to the extent that we were."

Tonnage is up by 60 percent and the number of participating customers has risen to 85,000 from 60,000 previously. Denver residents don't get visited by recycling trucks unless they solicit the service and request the necessary 64-gallon wheeled cart.

Denver's 10-year MRF contract locks in payments of $33 per short ton, minus an allowance for contamination. When prices are unusually high, incremental revenue is split 50-50 with the processor, calculated at year-end. That occurred in 2007 and probably will again for 2008, thanks to high prices in the first half of the year. But 2009 likely will be a different story, opening with a profound slump in commodity prices.

While single-stream recycling is growing in popularity, some operations require a more-stringent stopgap. At times, middlemen need to be involved, as has been the case with aluminum cans, where traditional scrapyards sometimes play a role between the MRFs and the sheet mills.

"Mills are getting pickier," said a spokesman at Chicago-based Universal Scrap Metals Inc. "The quality issues become more important in economic times like we're in right now."

Some MRFs with adequate equipment run their lines too fast to achieve the results that mills seek, he said. "I'm usually buying bales of finished product from the MRF, breaking the bales and reworking them through our cleaning system to make them mill spec. We pay only for the aluminum that we recover and we don't pay mill prices. But it's a no-hassle option for people on the waste-hauler end." After all the eddy currents and magnets and cleaning, the processing line ends with a human check workers peering at the material to spot anything the machines might have missed. PAUL SCHAFFER

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