Problem Set /For Practice(Q&A)-wastewater systems

To know and to understand are different. Even though you know, you need to put knowledge into practice in order to understand."

The purpose of this?problem set?is to help you to understand wastewater systems by giving you examples of the types of skills you may be asked to use.

we will solve 8 different types of question.

1. Which of the following indicates an alkaline wastewater?

a. 2

b. 6

c. 7

d. 12

2. Coliform bacteria are:

a. Sequestering agents

b. Indicators

c. Coagulant aids

d. Algae

3. BOD samples for compliance purposes must be collected as________.

a. A grab sample

b. A 12-hour composite sample

c. Either a grab or composite sample

d. A 24-hour composite sample

4. Facultative ponds are:

a. Completely anaerobic

b. Not used to treat wastewater

c. Aerobic on the top and anerobic on the bottom

d. Completely anaerobic

5. What is the detention time of a settling tank that is 35 feet long by 20 feet and is 15 feet deep and is used to treat 0.8 MGD?

a. 2.4 hours

b. 24 hours

c. 2.6 days

d. 0.26 hours

6. At what temperature are fecal coliform samples incubated?

a. 35oC

b. 44.5oF

c. 20oC

d. 100oC

7. In the enzyme substrate test (i.e. Colilert), which of the following reactions is considered positive for E.coli?

a. Well is yellow and not fluorescent under 365nm UV light

b. Well is colorless and fluorescent under 365nm UV light

c. Well is cloudy

d. Well is yellow and fluorescent under 365nm UV light

8. The E. coli results (#/100 mL) for an activated sludge plant for the month of July were 11.4, 4.1, 9.2, 6.3, 31.2, 11.4, and 14.7. What is the geomean for July?

a. 31.2

b. 10.5

c. 4.1

d. 12.6

Problem Set / For Practice (Answers)

1- D

2-B

3-D

4-C

5-A

6-B

7-D

8-D