The document discusses bioremediation, the process of using living organisms to address environmental issues, particularly through microbial action. It differentiates between in-situ and ex-situ bioremediation methods, detailing techniques such as bioventing, biosparging, bioaugmentation, and biostimulation, as well as solid-phase treatment processes like composting and mycoremediation. Case studies highlight the application of these techniques in treating petroleum and wastewater contamination.