Concrete groups are on tenterhooks, waiting for the U.S. Environmental Protection Agency to publish a proposed rule that aims to designate fly ash and other coal-combustion by-products as hazardous waste. The concrete sector is concerned even about the ramifications of a “hybrid” rule that would allow beneficial uses of CCBs to continue.
Major among these beneficial uses is fly ash in concrete. The ingredient, a partial replacement for portland cement, is known to increase concrete’s constructibility, durability and sustainability.