Failure analysis and root cause analysis (RCA) of corroded pipelines and piping system components can provide operators with valuable information to help prevent future failures while optimizing mitigation costs. If a corroded pipe sample is not handled or preserved properly because of inadequate planning, the ability to diagnose the corrosion mechanism(s) is lost. Using some basic steps for preparation and investigation, operators can determine the applicable corrosion mechanism(s) causing the corrosion and implement or adjust the measures taken to mitigate the corrosion. Collecting multiple lines of evidence about chemical and microbiological conditions, corrosion products, and operating parameters is essential. Further, with the increasing use of molecular microbiological methods (MMM), the role of microorganisms can be determined with greater certainty than has been possible in the past. Targeting mitigation measures to only the applicable corrosion mechanism(s) can support mitigation cost optimization, such as byapplying only the correct chemical treatments rather than an all-encompassing “security blanket” approach.

Key Words: Corrosion failure analysis, microbiology, pipeline integrity, RCA, MIC, FCE, qPCR