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In 2005, The Miller Group Inc., based in Morrow, GA, completed 75 centerline miles of Full Depth Reclamation (FDR) for South Carolina's District 4 Department of Transportation. The northwest district consists of Cherokee, Chester, Chesterfield, Fairfield, Lancaster, Union and York counties. Many of the secondary low-volume roads were beginning to show their wear, with poor subgrade materials and some heavy truck traffic taking its toll on the structures.

FDR is a process that recycles the existing roadway along with a pre-determined depth of subgrade material mixed with an additive to form a new road base. For South Carolina's District 4, FDR provides a cost-effective way to improve and preserve secondary roads, allowing the road agency to address more road miles in less time and at a significant savings over conventional methods used in reconstructing roadways.

The FDR preservation approach also enabled District 4 to make the roads safer by widening many of the roads, some that were only 18-feet wide, to 24 feet — allowing for 10-foot-wide travel lanes and 2-foot-wide shoulders.

During the project, Miller Group processed approximately 450,000 tons of material, while only hauling 25,000 tons of Portland cement additive. Using a conventional reconstruction method, 600,000 tons of material would have been trucked out and into the project. But recycling the material on the project not only saved a considerable amount of money for the road agency, it also helped to improve the overall structural characteristics of the roads treated, with the DOT specifying the cement additive application rate of 48 pounds per square yard. The depth of the new recycle base was specified at 8 inches, but in some areas Miller's crews went deeper to fully blend deeper sections of pavement.

After the FDR based cured for seven days, Everett Dykes Grassing of Cochran, GA applied a chip seal surface treatment to the roads. The paving contractor applied a triple surface treatment — two layers of chip seal using a cationic rapid set emulsion and a final sand sealer coat to hold the aggregate chips in place.