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BOD entering treatment is 200 mg/L. The effluent BOD is 20 mg/L. What percent was removed?
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Curated values teach the governed percent-removal relationship. They are not permit limits, treatment requirements, performance targets, design criteria, operating recommendations, certification weighting, or claims about a specific plant.
This Draft family uses selected mathematical facts only. It does not reproduce an official formula sheet or claim how an official exam weights topics.