ABSTRACT
This chapter discusses the potential for natural bioremediation to be incorporated into an overall remedial design at a hazardous waste site. It addresses the various biological processes using oxygen, nitrate, ferric iron, sulfate, and carbonate as electron acceptors. The chapter considers the effect of environmental conditions on biodegradation, site characterization needed for natural bioremediation, necessary parameters to be monitored, performance and prediction of natural bioremediation, and issues that may affect the costs associated with the technology. It also presents well-documented case studies of natural bioremediation at former wood preserving facilities and petroleum releases. Almost all petroleum hydrocarbons are biodegradable under aerobic conditions. Hydrocarbon biodegradation is essentially an oxidation-reduction reaction where the hydrocarbon is oxidized (donates electrons) and an electron acceptor (oxygen, nitrate,) is reduced (accepts electrons). Dissolved hydrocarbons are among the most common ground-water contaminants and can originate from spilled fuels, solvents, wood preservatives, and coal gasification wastes.
