Concrete, in our impression, is incredibly strong, but it may be quietly gnawed on by microorganisms that are invisible to the naked eye.
This process begins in a sewage environment: at the bottom of the oxygen deficient pipeline, sulfate reducing bacteria convert sulfides into hydrogen sulfide gas with a foul egg odor.
When these gases enter the aerobic space at the top of the pipeline, sulfur oxidizing bacteria begin to work, oxidizing hydrogen sulfide into highly corrosive bio sulfuric acid.
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