Several years ago Scott County received a grant from the Iowa DNR to establish a facility to process construction and demolition material before it entered the landfill. One of the goals for this facility was to identify and recover potential recyclables and to lower the percentage of the construction & demolition material that made it to the landfill. Recycled asphalt shingles was one known potential material. Scott County reached out to two local hot mix asphalt operations. McCarthy's Linwood mine facility was adjacent to the landfill, and a program was begun.

The process of recycling asphalt shingles begins with them being sorted, cleaned, and tested for asbestos. Then a machine grinds the asphalt shingles down to either 1/2" or 3/8" size while a magnet removes nails and metal.

One benefit of using the waste shingles in hot mix asphalt if that they both contain many similar ingredients like asphalt cement, rock granules, and fibers. Another benefit is that the shingles are roughly 20% asphalt by weight, but Asphaltic concrete is only 6% asphalt by weight; therefore, a small percentage of recycled shingles can replace a much larger percent of the new asphalt product that is used during the standard process. A final benefit is using waste shingles is that the application process is exactly the same.

The seminar and demonstration has proved that using recycled asphalt shingles in hot mix asphalt works the same as the standard procedure used today but costs the contractor less money and is less harmful to the environment.                  -Joe Bush