A new University of Washington study has confirmed the best option for disposing of unused food and yard waste is composting rather than sending it to the landfill.
Food waste generates the greenhouse gas methane when it decomposes in landfills, but not when it's composted. Cities such as Seattle with municipal composting avoid generating a large amount of methane as a result of keeping the organic materials out of the landfill.
The study shows that food waste is universally better suited to composting than landfills. For yard waste, there are more variables involved and in some regions the waste may break down more slowly in landfills than in others, creating less methane. However, even though the variations make it hard to quantify the environmental benefit of composting yard waste, mixing yard waste and unused food provides a better mix for the composting process.
The study was conducted by Sally Brown, a research associate professor of environmental and forest sciences. The study looks at the benefits of composting using a new model by the Environmental Protection Agency.