A recycling efficiency project helps you measure what happens to waste in a home, classroom, or school during one week. Instead of guessing how well a recycling program works, you collect real data by sorting items into recycle, compost, and landfill groups. This makes waste visible and turns everyday choices into a science investigation.
The results can guide practical changes that reduce trash and save resources.
Key Facts
- Total waste = recycle mass + compost mass + landfill mass
- Recycling efficiency = recycle mass / total waste × 100%
- Diversion rate = (recycle mass + compost mass) / total waste × 100%
- Landfill percentage = landfill mass / total waste × 100%
- Use the same unit for every category, such as grams, kilograms, or pounds.
- A pie chart sector angle = category amount / total amount × 360°
Vocabulary
- Waste audit
- A waste audit is a planned count or measurement of trash materials to learn what types of waste are being produced.
- Recycling efficiency
- Recycling efficiency is the percentage of total waste that is correctly placed in the recycling stream.
- Compost
- Compost is organic material, such as food scraps or leaves, that can break down into nutrient-rich soil material.
- Landfill
- A landfill is a managed site where waste is buried when it is not recycled, composted, or reused.
- Contamination
- Contamination happens when the wrong items or dirty materials are placed in a recycling or compost bin.
Common Mistakes to Avoid
- Mixing units, such as grams for recycling and pounds for landfill, gives incorrect percentages because the category amounts are not directly comparable.
- Counting items instead of measuring mass can be misleading because one large cardboard box may weigh much more than many small wrappers.
- Including contaminated recyclables as successful recycling overestimates efficiency because dirty or incorrect items may be rejected from the recycling stream.
- Forgetting to include compost in the total waste makes the denominator too small, which can make the recycling efficiency look higher than it really is.
Practice Questions
- 1 A classroom waste audit finds 6 kg of recycling, 3 kg of compost, and 9 kg of landfill waste in one week. What is the recycling efficiency percentage?
- 2 A school cafeteria records 12 lb of recycling, 18 lb of compost, and 30 lb of landfill waste. What are the diversion rate and landfill percentage?
- 3 A school has a low recycling efficiency even though many recyclable items are present in the landfill bin. Give two likely causes and recommend one change that could improve the next week's results.