| By-products produced from the combustion of coal prior to 1993 had been designated as hazardous wastes and were primarily disposed of in landfills. In order to utilize these by-products, companies had to obtain the required applications and special permits. In August of 1993, the EPA determined that these by-products should be classified as non-hazardous and therefore would be regulated by individual states. This ruling opened the door for beneficial use projects such as Autoclaved Cellular Concrete, sub-bases for roadways, structural fill, soil stabilization, grouting, and other beneficial uses. This paper investigates the utilization of coal combustion by-products and discusses any deleterious effects that NOx reduction techniques could have on their usage. |
