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How Composting Works


Trash Audit

How much trash does your family make in a year? What kind of things do you throw away? How much can be reduced by recycling or composting? To answer these questions, perform a trash audit.

  1. Estimate the total trash you produce in a year:
    • Take a week's worth of trash in garbage bags and weigh or estimate the volume of each bag. Assume the bag is a sphere, so volume = 4.19 x radius3.
    • Multiply the weight or volume by 52 weeks.

  2. Determine the make-up of your family's trash:
    • Wearing rubber gloves, sort through the garbage bags and separate the trash into various garbage bags for different categories of trash, such as glass, newspaper, plastic bottles, aluminum cans, white bond paper, glossy paper/magazines, fruit/vegetable food waste, meat/dairy food waste, non-food waste and yard waste.
    • Seal and weigh or estimate the volume of each individual category bag (volume = 4.19 x radius3).

  3. Determine the percentage of total trash for each category:
    • Divide the weight or volume of each category's trash bag by the weight or volume of the combined trash.
    • Multiply each quotient by 100.

  4. Look at the categories and determine what percentage of your trash output you can reduce by recycling or composting.
    • You can recycle such items as glass, newspaper, glossy paper, aluminum cans, aluminum foil and plastic bottles.
    • You can compost newspaper, yard waste and most kitchen wastes (although meat/dairy products take special composting).
    • You can see how much of your garbage is made up of packaging, some of which may be excess packaging. You can reduce this trash category by buying products with minimal packaging, such as bagged cereal instead of boxed cereal.

If you can reduce your trash output by recycling and composting, you can save landfill space and reduce your town's waste expenses, which can ultimately lead to better uses for your tax money.

For more information on composting and related topics, check out the links on the next page.


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