Hazardous Waste — Treatment

Hazardous waste can be treated by chemical, thermal, biological, and physical methods. Chemical methods include ion exchange, oxidation and reduction, precipitation and neutralization. Among thermal methods is high-temperature incineration, which not only can detoxify certain organic wastes but also can destroy them. Specific types of thermal equipment are used for burning waste in either solid, liquid, or sludge form, including the rotary kiln, liquid-injection incinerator and fluidized-bed incinerator.

Hazardous wastes may only be deposited in "secure landfills", which provide at least 3 meters (10 feet) of separation between the bottom of the landfill and the underlying bedrock or groundwater table. A secure hazardous-waste landfill must have two impermeable liners and leachate collection systems that prevents the accumulation of leachate trapped in the fill and prevents environmental damage. To further reinforce against environmental contamination, an impermeable cap or cover is placed over a finished landfill.