THE EFFECTS OF CODISPOSAL OF ALKALINE HAZARDOUS-WASTE WITH MUNICIPAL SOLID-WASTE OF LEACHATE CONTAMINATION

Landfill codisposal of industrial waste (IW) and municipal solid waste (MSW) was conducted in test columns. The IW studied in this work was a steel flue dust from an Ontario steel manufacturer and was classifie d as a hazardous material. There were 7 columns used in this study. Th ree of them were packed with 100%MSW while other four were packed with MSW + 8%IW. One 100%MSW and two MSW + 8%IW columns were closed and re ceived controlled water additions, while other four columns were open and received water input from precipitation. The column study was carr ied out over a relatively long term in order to investigate the conseq uences corresponding to codisposal of IW in a municipal solid waste la ndfill. The results obtained over an operational period of 2300 days a re reported. The presence of the steel flue dust layered between MSW a ccelerated the stabilization of the waste which was shown by a more ra pid decrease in COD and neutralization of leachate from the columns co ntaining MSW + IW compared to the columns containing MSW only. At the same time no significant increase in release of ions such as Ca, Mg an d heavy metals into leachate was observed when compared to disposal of MSW alone. Elements having very soluble salts showed an increase in t he release of ions corresponding with an elevated level of the element s in the industrial waste.