A municipal wastewater treatment plant with average flow of 1.5 MGD and maximum flow during the day is 2.6 times the average hourly flow has decided to design a circular sedimentation basin. The overflow rate based on the average daily flow is 800 GPD/ft? and the same based on the peak hourly flow is 1800 GPD/ft?. The minimum depth of the basin would be 10 ft. For the proposed basin (a) determine the diameter (b) the design diameter of the tank if sludge rake equipment is available in 5-ft increments in diameter.

Find the total amount of suspended sediment per unit width of a river according to the velocity profile and suspended sediment concentration given in the following table. Depth (m) 0.05 0.5 1.0 1.5 2.0 2.2 1.53 1.73 1.41 0.71 Velocity (m/s) Concentration(m³/10ʻm³) 1.21 0.31 111 113 211 313 411 611

1) Determine time of concentration, tc, for use the NRCS Method for a drainage basin located near Bismarck, North Dakota, having a hydraulic path described as follows: Overland Flow: average grass, 100' long, 1.6% average slope Shallow Concentrated Flow: 680' long. 3.2% average slope Stream Flow: 2950' long, 0.61% average slope, in a trapezoidal Channel, 4 ft deep, 12 ft at the base, 20 ft at the top, n = 0.035.

The figure is a plan view of a confined aquifer showing two contaminated zones, 1 and 2. The aquifer has a saturated thickness of 80 ft, hydraulic conductivity of 42 ft/d, and the regional hydraulic gradient is 0.0075 from right to left as shown. A pumping well with a flow rate of 170 gpm is planned to run continuously at the location shown, and form a stable (equilibrium) capture zone. You may assume that the 2500 ft distance from the well to zone 1 is long enough that the capture zone has reached its maximum width. 2 200 ft Determine: pumping well 2500 ft 700 ft regional flow direction 1. If contamination from zone 1 find its way to the pumping well? Provide support for your answer with a capture zone analysis or contaminant simulation model. 2. If contamination from zone 2 find its way to the pumping well? Provide support for your answer with a capture zone analysis or contaminant simulation model.