Analysis of Scientific Investigations Related to Reclamation of Surface Mining Control and Reclamation Act Permitted Coal Mines with Coal Combustion By-Products

In the United states, the placement of coal combustion by-products (CCBs) (i.e., fly ash, bottom ash, boiler slag, flue gas desulfurization material, and fluidized bed combustion material) in coal mines has been an area of controversy. Federal and state governments, universities, the National Energy Technology Laboratory, and industrial research organizations have taken an active role in encouraging and promoting technological advances, research, and technology transfer related to the use of CCBs at coal mines. CCBs have been placed at Surface Mining Control and Reclamation Act of 1977 (SMCRA) permitted mines since 1977 to serve the following purposes: (1) a seal to contain acid-forming materials and prevent the formation of acid mine drainage; (2) an agricultural supplement to create productive artificial soils on abandoned mine lands where native soils are not available; (3) a flowable fill that seals and stabilizes abandoned underground mines to prevent subsidence and the production of acid mine drainage; (4) a construction material for dams, roads, or other earth-like materials where such materials are needed as a compact and durable base; (5) an alkaline additive used to physically and chemically stabilize coal refuse during disposal; and (6) an earth-like fill material used to achieve approximate original contour for final pits and within the spoil area (K. C. Vories, Proceedings of the International Conference on Coal Ash: Coal Ash– A Valuable Resource, 2006). This article examines the findings of a wide range of scientific investigations that have evaluated the environmental impacts of CCB placement at SMCRA permitted sites. It also evaluates the findings of the National Research Council in their investigative report completed in 2006 and evaluates its merits as potential evidence for or against the development of additional rulemaking at either the state or national level.