The newspapers are bundled. The cans are separated from the plastic. All is set outside for the recycling truck. This is being environmentally responsible, right?
Unfortunately, such individual acts are often thwarted by a recycling system that doesn't quite work. Some things cost too much to reprocess, so they're pitched.
Many community recycling programs are still figuring out what works. But for the past seven years, researchers at Carnegie Mellon University in Pittsburgh have been refining computer software that tells business what to recycle and what to throw away. They've learned some valuable lessons along the way.
''It's really a money game,'' says D. Navin-Chandra, the professor at the university's computer science school who spearheaded the project. ''Causing environmental damage is expensive for companies.''
It costs money to put things in landfills. It also wastes parts that could be reused. So a growing number of firms are recycling. ''It's worth millions of dollars to Xerox Corporation,'' says Jim Cleveland, manager of remanufacturing strategy and operations for the Stamford, Conn., manufacturer of copiers and printers.
Xerox has recently stepped up its recycling efforts. Instead of letting machines it got back through trade-ins or expired leases molder in warehouses, the company now develops a recycling plan as soon as it introduces a new product. It now remanufactures parts valued as little as $15.
The program not only saves money, it also lets Xerox build better machines. For example, the company routinely reuses copier and printer rolls that press the toner onto the paper. The process requires an intensive stripping of the old roll - so intensive that it was deforming the aluminum shafts inside the roll. So the company replaced the aluminum with more-durable stainless steel. These rolls cost more to make, but Xerox can recycle them an average of 10 times instead of just once, Mr. Cleveland says.
IBM is another company that has changed the way it makes new products to make them easier to remanufacture. ''It's stupid to put everything in landfills,'' says J. Ray Kirby, manager of the company's Engineering Center for Environmentally Conscious Products. Its four-year-old recycling effort hasn't shown a profit yet, but it has paid for itself, he says. The company expects to recover significantly more from its personal and mainframe computers in the next few years.
The Carnegie Mellon software calculates the optimal mix of what to throw away and what to reuse. It also helps companies focus on recycling parts that make the most economic sense. Communities should do the same, Professor Navin-Chandra says.
Budget cuts are already forcing some communities to take a closer look at their collection systems. Nashville officials are casting about for a cheaper system because they found they were paying an average of $2 to pick up 6 cents worth of recycling material. State cuts in recycling subsidies are causing Citrus County, Fla., to replace its curbside-pickup program with a network of drop-off centers that will cost one-tenth as much.
Such cost-saving moves may mean communities recycle less and throw away more in the short term. And that certainly doesn't solve the problem, environmentalists argue. ''When you've got to the point of burying something or burning something, you're burying the evidence of something wrong in manufacturing,'' says Paul Connett, a chemistry professor and environmental activist at St. Lawrence University in Canton, N.Y.
But surely it is better to expose those areas where recycling isn't working, as this software does, than to lull citizens into a false sense of security. That way, we won't be left wondering what really happened to that plastic bottle in the recycling bin.
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