Besides promoting mixing of the bacterial population with the fecal waste material, what is the purpose of aeration system as used in a biological sewage treatment plant?

Correct Answer: Option D — The air provides an oxygen source for the aerobic bacteria required for metabolism, and it helps prevent settling in the aeration chamber.

Under USCG National Maritime Center examination standards, the accepted correct answer is: The air provides an oxygen source for the aerobic bacteria required for metabolism, and it helps prevent settling in the aeration chamber..