By Carolyn Grodinsky and Jim Surwilo Recyclable materials such as crushed glass, shredded tires, composted yard waste and crushed concrete provide towns with an opportunity to save natural resources and taxpayer money. Some Vermont communities are already using recycled materials in municipal projects. The City of South Burlington recycles all of its concrete, brick and asphalt and uses it as aggregate for new projects. Mixed-color glass can also be used as aggregate. Glass that has been crushed, screened to remove contaminants and mixed with natural aggregates can be used in utility trench bedding, backfill and roadway construction.
Tires are also a proven aggregate substitute.
Vermonters generate about 600,000 scrap tires each year. But tire shreds are durable, weigh nearly 50 percent less than crushed stone and provide good insulation making them extremely useful for many municipal projects. Tire shreds have successfully been used in Vermont as lightweight retaining wall backfill, sub-base on town highways, stone replacement in septic systems and lightweight embankment fill. Unfortunately, Vermont s only tire processor stopped producing shreds last year, but communities can still get shreds from Maine, Massachusetts and New York. Although shreds will sometimes cost more than local stone or gravel, when weight or insulation is a major factor, tire shreds can be the least expensive option for towns.