1. Construction defects that cause problems in wastewater collection systems include _.
a. improper grade of sewers
b. improper taps
c. structure failure of manholes
d. all the above
2. A venturi meter measures quantities of fluid by _.
a. difference in pressure between a constricted and a full-sized portion
b. electronic measurement
c. velocity of the fluid past a given point
d. weight of the fluid
3. How can the members of a balling crew communicate with each other?
a. hand signals
b. shouting down the sewer
4. Which of the following is the most common factor leading to the generation of hydrogen sulfide in sewers?
a. anaerobic conditions
b. constantly high velocity of flow in the sewer
c. low concentrations of ferrous sulfide
d. presence of highly soluble fats and oils
5. When sewer line grades are too flat, an odor problem is likely to result. The most likely cause of the odor problem is decreased velocity which _.
a. allow decomposable solids to settle
b. decreases the treatment time in the lines
c. increases the treatment time of inorganic solids
d. none of the above