Problem 1. Incoming wastewater, with a BOD5 equal to 200 mg/L is treated in a well-run treatment plant that removes 90% of the BOD. I will run a 5-day BOD

test with a standard 300 mL bottle using a mixture of treated sewage and dilution water. Assume the initial DO is 9.2 mg/L in the BOD test.. A. What is the maximum volume of treated wastewater that I should put in the bottle if I want to at least have 2.0 mg/L of DO at the end of the test. B. If you make the mixture half dilution water and half treated wastewater, what DO would I expect after 5-days.

Fig: 1

Fig: 2

Fig: 3