ABSTRACT
Many groundwater supplies are contaminated by varying levels
of iron (Fe), manganese (Mn), and arsenic (As) in concentrations
that exceed the drinking water guidelines. Fe and Mn are removed
from water supplies mainly for aesthetic and operational objectives,
whereas As must be removed from drinking water because of
its numerous health hazards. Conventional treatment methods for
removal of Fe2+ and Mn2+ from groundwater are based on physicochemical processes such as aeration, chemical oxidation, coagula-
tion, and rapid sand filtration. An alternative method is based on
biological process of Fe and Mn oxidation and deposition mediated
by microbial consortia fixed in biological filtration reactor. In
addition, this method is possibly applicable to As removal, since
soluble As oxyanions are known to be adsorbed onto Fe and Mn
oxides produced by the biological treatment process. In this chapter,
research advances toward unraveling the mechanisms of biological
treatment of Fe and Mn, as well as the potential application of
biological Fe and Mn oxidation processes for As removal from
groundwater are discussed.
