Leachability and content of heavy metals in incombustible residues from resource recovery facilities

The heavy metal leachability and contents of incombustible residues (IR) generated from municipal resource recovery facilities were investigated. It was found that IR from residential bulky waste have both a higher heavy metals content and heavy metals leachability than IR from incombustible residential waste. Further, eluate concentrations for lead from some IR samples were as high as those from typical municipal solid waste (MSW) fly ash. Leaching experiments using four lysimeters were performed. It was found that lead concentrations in leachate from the lysimeters containing only IR were very high, although leachate concentrations from those lysimeters containing mixtures of IR and MSW bottom ash decreased more rapidly. These findings suggest that codisposal of IR with bottom ash could significantly decrease the leachability of lead.