Bacterial, chemical, and mineralogical characteristics of tubercles in distribution pipelines

Abstract

Tubercle deposits collected from pipelines in the Columbus, Ohio, distribution system and examined for their microbiological, chemical, and mineralogical composition were found to contain several kinds of organisms, including sulfate reducers, nitrate reducers, nitrite oxidizers, ammonia oxidizers, sulfur oxidizers, and various unidentified heterotrophic microorganisms. Chemical analysis revealed that the tubercles consisted largely of iron oxides, although minor and trace elements were present in varying quantities.