Which hazardous waste management practice involves the thermal destruction of wastes?

The practice that involves the thermal destruction of wastes is incineration. This process uses high temperatures to combust hazardous waste materials, transforming them into gas, ash, and heat. Incineration is particularly effective for managing hazardous wastes, as it helps to reduce the volume of waste significantly and can destroy harmful organic compounds that might otherwise pose environmental and health risks.

In contrast, landfilling involves the disposal of waste in a designated area, where it is separated from the environment but not destroyed. Recycling focuses on reprocessing materials to create new products, which does not involve thermal destruction. Composting is a method used to decompose organic materials using microorganisms, again not involving high temperatures or combustion.

Thus, incineration stands out as the correct answer due to its thermal destruction capabilities.