Student Handout

Composting
Composting is the rotting of organic material such as grass trimmings, leaves and food waste into a nutrient-rich material that can be used on gardens as fertilizer or soil enhancer. Yard and food wastes typically account for 20-30 percent of the waste stream. This means there is an opportunity to divert a large part of the waste stream to be composted. Many communities have started or are evaluating setting up a compositing facility. Also, many families are setting up composting bins in their backyards and mulching grass clippings from their lawns.

Garbage doesn’t decompose very well in landfills because it is tightly packed and covered with soil. To make compost, air, water, heat and soil microbes must be present. Compost piles are turned frequently so all these factors will be at work. Although composting has several advantages, such as producing a useful product and being inexpensive, it also has some disadvantages. Only organic materials can be composted. Also, rarely do people want to live next to a large compost facility. As compost decomposes, it smells like rotting garbage and is quite unpleasant for those people living close by.

Recycling
One very popular way to divert materials from the waste stream is recycling. Recycling is the remanufacture of a material after it’s been used. It may be turned into the same thing or something different. Recycling efforts have reduced the amount of material going into landfills. Of course, many waste products are not recycled. The data table shows the percentages of materials that are being recycled and the estimated amount that it is practical to recycle.

The important thing on this chart isn’t what the recycling rate is now but the maximum practical rate in the future. It isn’t practical to collect and recycle everything, especially considering that the reason we recycle is to save resources. If it takes more resources to recycle an item than to produce a new one, the item should not be recycled.

Recycling has become very popular in the past few years. Unfortunately, recycling has frequently grown faster than recycling facilities can handle it, manufacture it into new products, and find markets for the products.

Collecting items for recycling isn’t effective if no one is willing to buy the recycled materials and make new products. Unless people are willing to buy the recycled products, companies won’t produce them. For example, most plastic bottles are recyclable, yet when was the last time you looked at a bottle to make sure it had recycled content?

Some products such as paper cannot be recycled continuously. The wood fiber in paper gets shorter as it goes through the recycling process, and eventually it cannot be further recycled. Some materials may require too much energy to be recycled efficiently.

This is especially true if the materials to be recycled are too far away from collection or manufacturing facilities. Does it make sense to ship glass 1,000 miles to be recycled and use more fuel to get it there than is saved by recycling?

The bottom line is that recycling has many advantages. It reduces the amount of garbage going to waste facilities, and in many instances, it can save energy and not create pollutants. But recycling is not a cure-all. It is a process like any other, in that it uses energy, creates its own pollutants and has its own costs. All of these factors must be weighed when deciding how best to reduce waste disposal.

Incineration – Or Waste to Energy
Modern incinerators burn garbage and nearly all of the plants generate electricity from the heat. An incinerator burns trash such as paper, plastics and broken furniture, turning them into electricity instead of sending them to a landfill. This seems like a better way to make electricity than damming rivers or burning coal or oil. Unfortunately, these plants are very expensive to build and run.

Earlier incinerators produced a lot of smoke and pollution. Now, they burn at very high temperatures and have special equipment that eliminates most of the pollution. Incinerators produce ash just like a fireplace does. Typically, the burned trash is reduced to one-tenth its volume and one-fifth its weight. The ash is tested for hazardous materials and if the hazardous content is too high, it must be disposed of in special landfills. Fortunately, most ash isn’t found to be hazardous. By the way, batteries are sometimes listed as hazardous waste that cannot be incinerated and must be sent to expensive toxic waste facilities.

Landfills
A landfill is more than a big hole in the ground. New landfills are designed with special clay and plastic liners to trap liquids, such as rain, which might seep through. Older landfills (often called dumps) had no liners and water and other liquids would soak down through them, sometimes polluting nearby wells and bodies of water.

Regulations now prohibit the disposal of hazardous material in a landfill. When the landfill is filled, it is covered with a membrane and dirt and often turned into a park or golf course. We often read that we are running out of landfills. For example, we used to have more than 15,000 landfills in the United States; by the year 2000, only 2,000 were expected to remain. But these numbers do not tell the whole story. Many of the landfills were old, designed improperly and should have been shut down. Also the new landfills that replaced them can be very large. In one case, three regional landfills had a greater capacity than the 500 “dumps” that had been closed. So it’s not the number of landfills, but their capacity that’s important.

The biggest problem for new landfills is the same as for incinerators and compost facilities — few people want to live next to one. This is called the NIMBY (Not In My Backyard) syndrome. Coupled with the high cost of building and maintaining new facilities, the NIMBY syndrome could lead to landfill shortages in some communities in the future.

Conclusion
We’ve just summarized the four primary methods of dealing with garbage. No method is perfect or capable of dealing with all our trash. Wouldn’t it be nice if we didn’t have to worry about what to do with trash? What if we didn’t create so much in the first place?

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