using the table given

Table 1: Data for Problem 6 Sampling Port Depth, ft ; ; 2 4 6 8 Time, min 0 0 0 0 0 10 28 18 18 12 20 48 39 25 27 30 68 50 34 31 45 70 56 53 4] 60 85 66 59 53 90 88 82 a 62 Problem 6 A circular sedimentation tank is designed to treat a flocculated water having 320 mg/l suspended solids and a flow of 2.0 MGD. A batch settling test was performed using a 8 in diameter, 10 ft high column with withdrawal ports every 2.0 ft. The reduced data giving the percent removals are shown in Table 1. Determine: 1) the design detention time and overflow rate if 65% of suspended solids are to be removed and 2) the design diameter and depth