Corrosion Control If sequestration of iron and manganese is practiced, the chlorine residual in the water system should always be maintained at or above: Tags: Certification Exam Prep, Chlorine Residual, Distribution System, Iron, Manganese, Sequestration, Water Treatment Read more articles Previous PostWater Treatment and Distribution SystemNext PostWater Treatment and Distribution System You Might Also Like A Whole New Year! January 4, 2016 Visual Study Tools February 27, 2019 Water Main Installation January 29, 2017 Post author:jay@americanwatercollege.org Post published:January 11, 2017 Post category:Certification Exams / Distribution / Water Treatment