Studies were conducted to investigate the feasibility and effectiveness of solidification/stabilization of hazardous heavy metal‐laden sludges with portland cement. The results indicated that the sludge properties had a significant effect on the compressive strength of the solidified samples. Additives such as lime, sodium silicate, calcium chloride, and fly ash could enhance the compressive strength and reduce the leachability of heavy metal. Also, leaching studies indicated that stabilization minimized or prevented the release of heavy metals and created a nonhazardous product.