A 1,200 gpm WTP is being designed for treating iron and manganese. The influent manganese concentration is 80 mg/L and the iron concentration is 90 mg/L. How much oxygen (mg/L DO) from aeration is needed for design? Assuming that aeration only removes 85% of Fe and Mn, how much potassium permanganate is needed (mg/L)? Design standards require 30 days of chemicals onsite. Assuming that the chemicals onside are dry, how many lbs of potassium permanganate are required? If the treatment plant is to operate two filter cells at a time, what is the required SA of each cell, assuming SOR of 2.5 gpm/sqft?