The Universe on Blacktop

One of the reasons I occasionally find myself in a dumpster in my Colorado town has to do with a woman in India that I've never met. I've seen a photo of her, though, and that's enough to convince me of the need to climb around dirty diapers and cans of cat food. In the photo, this woman is holding her hands out, as if to ask why, and her face is splattered in blood.

Actually, I'm not the only one in a Colorado dumpster today. My two children and a friend, Tim, a geologist and dumpster-diving guru, are also in the stinky mess, tossing cans over the side, winging them high up so they can arc down with a tinkling clatter. We love dumpster diving anyway, but today is particularly perfect: We've found lots of huge bags of pop cans, aluminum doors from a construction site, and several pieces of aluminum tubing.

"Aluminum Day," my son declares it, and it wasn't until recently that I understood what this meant, or how important it was.

Aluminum is a funky material: It's the most abundant metal in the Earth's crust, its symbol is Al, its atomic number is 13. But the most important thing to know is this: Aluminum is too chemically reactive to occur in nature as the free metal, and so it gets "locked in" with other elements, especially bauxite ore. And it takes an incredible amount of energy to break those bonds and free it up.

Which means, basically, that when you hold an aluminum can in your hand, you're holding a lot more than the element. You're holding a bit of a strip mine and accompanying tailings piles, a power plant, and a smelter. You're also holding bits of boats and trucks and trains and the fuel required for the transportation, not to mention the aluminum-can and soda-making factories. And perhaps most importantly of all, there is the human and cultural cost -- for example, the Odivosis peoples in Orissa, a state in Eastern India that is rich in mineral deposits but poor in honoring the rights of indigenous peoples, who suffer at the hands of mining companies. A group of peaceable Odivosis women who were protesting a Canadian bauxite mine in their back yard recently got beaten up -- hence the bloody picture, and hence my sorrow at seeing aluminum cans in the trash. 

But oh, how I hate the preachy and judgmental types. So I'll stick to the numbers: While digging out beer cans from the dumpster (which sits exactly two feet from a recycling bin), Tim and I consider the facts. Recycled cans take 95 percent less energy than aluminum obtained from bauxite. About 30 aluminum cans are produced from one pound of aluminum, and each aluminum can requires about 3000 BTUs to produce it. So, Tim tells me, every two or three cans we recycle basically saves one pound of coal.

All this sounds complicated, but it's not. Not when you look up at the sky and consider what three cans means in the bigger picture of a clean and pure sky.

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