What’s in Your Garbage?
Conducting school waste audits
The Oregon Green School application requires that you evaluate your school’s waste as part of your planning process. If you know what is being thrown out, and from where, you can make a plan for reducing and recycling. Contact your local Green Schools Coordinator for assistance.
Conduct a Waste Audit
Separate the garbage into categories (paper, glass, food waste, etc.) and measure the volume and weight of each type of item. This is the best way to know what’s in your school garbage. Think of it as a great hands-on math lesson. Follow the steps in the “What’s in Your Waste” guide.
Download the following materials to help you get started:
“What’s In Your Waste?”A guide to conducting a waste audit
There are two versions of the waste audit forms. The “Waste Audit (Simple)” form is downloadable here . The ” Waste Audit (Comprehensive, MS Excel Format) ” version adds some extra features, such as allowing you customize your findings and it automatically creates pie charts to help explain the results of your audits. Either version is fine to use for your application. Please click on the graphics below to download them. Following the activity, consider doing the “Talking Trash” activity which helps students to interpret the results and share their findings. Another fun project to consider is creating a Waste Audit Mural to hang up in your school cafeteria, hallway or entrance to share the results of your waste audit.
While there are many different approaches to doing waste audits, our step-by-step guide gives you one approach for doing the audits. It is also suggested that you look at the presentation which gives tips on how to do a waste audit. If you need signs to do your waste audit, you can download our waste audit signs.
| How do you “weigh in” compared to the average school waste stream? | |||
| Recyclable paper – | 28% | Garden materials – | 3% |
| Food waste – | 24% | Recyclable plastics – | 1% |
| Milk cartons – | 4% | Hazardous waste – | 1% |
| Recyclable metal – | 3% | Polystyrene – | <1% |
| Recyclable glass – | 3% | All other wastes – | 32% |
(EPA 1993 Education Waste characterization Study)
| 1 cubic yard of: | (average) | |
| uncompacted but flattened cardboard = | 100 lbs. | |
| office paper = | 600 lbs. | |
| aluminum cans = | 65 lbs. | |
| mixed plastic bottles = | 32 lbs. | |
| glass bottles and jars = | 600 lbs. | |
| food waste = | 850 lbs. | |
| 1 Kilogram = | 2.205 pounds | |
| 1 cubic yard = | 27 cubic feet |
Helpful website for conversions: www.convert-me.com

