Published online by Cambridge University Press: 25 February 2011
Enormous amounts of coal fly ash produced by the utilities industry create a significant disposal problem. The abundance of fly ash along with its self-hardening properties led the Louisiana Department of Transportation and Development (LA DOTD) to use fly ash as a soil stabilizer for road bases. However, the LA DOTD is primarily concerned with the strength of the material and has not studied its leaching characteristics. In this study, a total of three samples, a 30 percent subbituminous fly ash/soil mixture, subbituminous fly ash, and soil, were leached following the EPA multiple extraction procedure and analyzed by Inductively Coupled Argon Plasma Spectrometry (ICAP). Results indicate that little change in leachate quality of subbituminous fly ash was caused by the soil stabilization process. The insignificant change is attributed to the low cation exchange capacity of the soil. ICAP analysis revealed that levels of toxic metals in the leachates are well within RCRA standards.