Waste immobilization techniques prevent the free movement of contaminants in waste. Three major types of immobilization
techniques, namely, the temporary containment techniques, cost effective solidification/stabilization techniques, and permanent vitrification
techniques are described. The purpose of this paper is to provide a comprehensive list of waste immobilization techniques with
sufficient descriptions including advantages, disadvantages, and limitations. The selection of an appropriate waste immobilization technique
depends on site conditions and type and amount of waste. Several temporary containment techniques such as pumping, capping,
draining, and slurry walls are discussed. Solidification/stabilization techniques can be either chemical or nonchemical. Chemical methods
are very popular and cost effective. Contaminated soils can be effectively solidified and stabilized using chemical methods, but the
resulting products may not always be reused as construction materials or consumable materials. Vitrification is an innovative technology
that incorporates hazardous and contaminated waste into a chemically, durable glass-like product. Vitrification can be either in situ or ex
situ. The containment techniques are usually used to ‘‘buy time’’ under emergency or temporary conditions. Contaminated soils can be
effectively solidified and stabilized using chemical methods, but the resulting products may not always be reused as construction materials
or consumable materials. The Environmental Protection Agency has declared vitrification to be the ‘‘best demonstrated available technology’’
for heavy metals and high-level radioactive waste.