Where does all the trash go?

Karin Landsberg, 42, a self-described “;eco-geek”; in Seattle, was so curious that she allowed researchers from the Massachusetts Institute of Technology into her home last month to fish 12 items out of her garbage and recycling bins—a can of beans, a compact fluorescent light bulb—and tag them with small electronic tracking devices.

Her trash is now on its journey to the place where it goes to die or be reborn.

The Architectural League of New York went through a similar trash-tagging exercise as part of the same project when it moved its offices from midtown Manhattan to SoHo two weeks ago. Among the discarded items tagged were a coffee cup, a filing cabinet, a book shelf, a broken wine glass and an empty plastic liquid soap bottle.

“;All they can tell me up to this point is that some of the stuff has gone through the Lincoln Tunnel,”; said Gregory Wessner, director of digital programs and exhibitions for the league. “;It is on the move. We're really excited to know what happens.”;

Through the project, overseen by MIT's Senseable City Laboratory , 3,000 common pieces of garbage, mostly from Seattle, are to be tracked through the waste disposal system over the next three months. The researchers will display the routes in real time online and in exhibitions opening at the Architectural League of New York on Thursday and the Seattle Public Library on Saturday.

One purpose of the project, said Carlo Ratti, director of the lab, is to give people a concrete sense of their impact on the environment, in a way that might lead them to change their habits.

“;If you see where a plastic bottle ends up, a few miles down the road in a dump, you may want to get tap water or some other container for the water,”; he said.

Collecting, transporting, storing and getting rid of garbage is a costly and often daunting task for cities. Lynn Brown, a spokeswoman for Waste Management Inc.—a company that runs both landfills and recycling centers nationwide and is helping to underwrite the tracking project with $300,000—said garbage moves through a vast network of sites run by multiple contractors, which makes it challenging to find the most efficient way to handle it.

It also means hundreds of possible journeys for trash. “;From a logistics standpoint, it's a very complicated situation,”; she said. “;When you look at how waste is handled in different cities, it's like snowflakes. It's all different.”;

Other factors are also in play in the travel of recyclables like metal and plastic, like price fluctuations that may make it cheaper for a company to ditch items than to recycle them, contamination that makes a can or paper useless, or human error in sorting or transporting material.

Even when an item is headed where it is supposed to go, “;does it fall off the boat, or truck, or whatever?”; said Landsberg, a transportation planner for Washington state. “;Is the stuff actually made into something useful in this country? Does it all end up shredded and shipped to China, where who knows what happens to it?”;

To answer some of those questions, the MIT team is using battery-powered tags based on cellular phone technology.

The researchers say it will take several months to analyze the data generated by the cellular signals. But they have already noticed that while some trash reaches its destination in a couple of days, other items may take four or five weeks to wind their way to landfills or recycling and waste processing plants.

In Seattle, where the researchers have already tagged about 500 items, an aluminum can disposed of at a residence traveled 2.5 miles to a recycling facility in the city in just under two days.

In New York, where 50 items were tagged at the Architectural League's offices, a plastic liquid soap container picked up at Madison Avenue and 51st Street traveled 18.3 miles over four days to Kearny, N.J., and is still en route—in principle, to a recycling center, said Assaf Biderman, associate director of the MIT lab.

The tracking has its limitations. Even though the tags have a battery life of two to six months and can report back from overseas, they can easily be crushed in transit inside garbage trucks and at processing facilities. Biderman said a paper cup taken from a Seattle residence sent signals for seven days before it went silent and is assumed to have been destroyed.

But the researchers say most tags are likely to travel far enough to show which items go where and how long it takes them to reach a destination, yielding information about inefficiencies in the waste management system. In coming weeks the project is expected to gain an international component when 50 items are tagged in London, Biderman said.

Brown of Waste Management said her company hoped that the experiment could eventually help shorten or avoid overlaps in routes traveled by its 24,000 garbage trucks and to find more central locations for transfer and disposal.

Ultimately, she said, “;we're looking for ways to recycle more and to do it all more efficiently.”;

Brett Stav, a senior planning and development specialist for the Seattle Public Utilities, which collects about 21,000 tons of trash and recyclables a day, said that aside from the help with logistics, he saw “;tremendous educational value”; in the experiment.

“;There is this hidden world of trash and there are ramifications to the choices that people make,”; he said. “;People just take their trash and put it on the curb and they forget about it and don't think about all the time and energy and money put into disposing of it.”;

The point is well taken by Landsberg of Seattle, who is so environmentally conscious that she keeps a worm bin to compost her food waste.

“;If I found out that it wasn't going where I think it does, if it is less recycled than I hoped,”; she said, “;I might think about buying less of it or doing without.”;

“;Maybe it is more about the reduce than the re-use.”;