In 1987, Kentucky put 40% power-plant bottom ash into 1 mile of State Route 3; later testing found excellent performance and strong skid resistance on the road

Engineers in Kentucky embarked on a pioneering project to incorporate bottom ash from coal-fired power plants into asphalt mixtures. Their findings revealed effective skid resistance and excellent friction performance, suggesting a viable avenue for recycling industrial waste in road construction. While promising, the results are pertinent only to this particular test, emphasizing the importance of investigating how industrial by-products can be effectively utilized in civil engineering projects.