Throw It Away!

I throw away a lot of stuff. I mean a lot of stuff. From used sticky notes when I’m at work, to the leftover remnants of a meal I couldn’t quite finish, to the seemingly never-ending stream of junk mail that barely makes it into my hand before it makes it into the trash, I certainly do my part to fill up my garbage can each day. In fact, we all do. On average, American households throw away 4.5 lbs. of garbage every day. All told, that adds up to roughly 250 million tons of garbage disposed of every year. Now, I’m no expert but that’s quite a pile of trash. It’s a good thing mining is around to help us dispose of it or we’d have quite the public health problem on our hands!

What it comes down to is landfills. Landfills are one of the primary ways cities and towns get rid of all the garbage their citizens generate on a daily basis. Landfills are essentially giant containers for a city’s garbage. Now, landfills might use quite a bit of dirt, but they’re also products of some surprisingly sophisticated engineering that depends on mining. Check out some of the ways in which mining plays a part in landfills:

- Liners: Landfills, as I said, are essentially giant containers for garbage intended to keep the garbage from coming into contact with the surrounding air, water, or soil. Liners are used on the bottom of landfills and can be made from plastic (municipal solid waste landfills) or clay (sanitary landfills). Both are products of mining.

- Storm Drainage System: A storm drainage system is what keeps rainwater out of a landfill. This rainwater is transported via concrete or gravel-lined ditches to designated collection ponds. The gravel and materials used to make the cement are called aggregates and are some of the most commonly used mined materials, particularly in cities.

- Covering/Cap: A landfill basically compartmentalizes garbage by packing it into a number of different “cells.” Each day, when a cell is filled with trash, it must be covered. Usually this is done with about six inches of soil, but recently some landfills have been experimenting with using synthetic coverings like tarps or cement/paper emulsions.  When a section of the landfill has been fully filled it is covered with a plastic cap. It’s a good thing mining is around to all that provide plastic and cement!

- Infrastructure/Transport: Have you ever seen a landfill located in the middle of a city? No? Good! Landfills are built in out-of-the-way location which often  means roads (made from aggregates) must to be built to reach them so that the garbage can be transported to the landfill. Speaking of which, those giant garbage trucks that pick up your trash to take it away to a landfill? Those trucks use no small amount of steel, a product of mined iron ore.

Ultimately, no matter what anyone says, I’m sure glad landfills and garbage trucks are around! Can you imagine how difficult it would be to have to dispose of all your garbage yourself? It’s just one more modern convenience made possible by mining!

DISCUSSION QUESTION: Have you seen or visited a landfill? What did you find interesting about the way it was designed or the way it used mined materials?