3) A group of neighboring municipalities decide to combine their waste streams and treat them all at one existing wastewater treatment plant, initiating a need to upgrade the plant's treatment capacity. The addition of the outside waste streams increases the UBOD loading on the plant to 45,000 kg/day which corresponds to a concentration of 238 g/m with a flow rate of 202,000 m/d. The wastewater discharged from the wastewater treatment plant is predicted to be at a temperature of 23C with no dissolved oxygen. The river upstream of the treatment plant has a flowrate of 5.5 m/s, an average temperature of 16.5C, no UBOD and a dissolved oxygen concentration equal to the saturation concentration. After mixing with the wastewater the velocity and average depth of the river are estimated to be 0.38 m/s and 2.7 m, respectively. To avoid interfering with downstream fish habitat, a minimum DO of 5 mg 02/L must be attained at 43 km downstream from the wastewater plant. The carbonaceous reaction constant for the mixed river and wastewater is 0.14 1/d at 20C. Determine the following: a) the deoxygenation (ka) and reaeration (kr) constants at 20C and at the mixed b) temperature. the effluent UBOD (Lw) required to have a minimum DO concentration of 5 mg O/L or above. c) the degree of treatment the wastewater treatment plant is required to implement to meet the required effluent UBOD. Is primary treatment sufficient?