Collection Systems

  1. What is the most common odorous gas that occurs in the collection and treatment of wastewater?
    1. Methane
    2. Hydrogen sulfide
    3. Chlorine
    4. Carbon monoxide

     

  2. Inadequate ventilation is the leading cause of confined space fatalities
    1. True
    2. False

     

  3. The rate at which hydrogen sulfide can escape from solution is a function, in part, of the pH of the solution. At which pH is more H2S likely to escape into the surrounding atmosphere.
    1. Acidic, pH < 7
    2. Neutral, pH 7
    3. Basic, pH >7

     

  4. The scouring velocity of a sanitary sewer should be
    1. 2 miles/hour
    2. 1 feet/second
    3. 2 feet per second
    4. 3.5 feet per second

     

  5. Which of the following is not a type of sanitary pumping station?
    1. Wet well/dry well
    2. Wet well only
    3. Dry well only

     

  6. A system of sewers which carries either sanitary waste only or storm water only is called
    1. Storm sewer system
    2. Combined sewer system
    3. Sanitary sewer system
    4. Separate sewer system

     

     

     

  7. An 18 inch sanitary sewer line has water flowing through it at a velocity of 5.9 feet per second. What is the gallon per minute flow rate through that sewer?
    1. 539 gpm
    2. 3.32 gpm
    3. 1490 gpm
    4. 199 gpm
  8. A fluorescent dye is used to estimate the velocity of the flow in a sewer line. The dye is injected in the water at one manhole and the travel time to the next manhole 550 feet away is recorded. The dye first appears at the downstream manhole in 145 seconds and is visible for another 30 seconds for a total elapsed time of 175 seconds. What is the velocity in feet per second of the flow?
    1. 3.4 fps
    2. 3.8 fps
    3. 3.1 fps
    4. 1.7 fps
  9. When entering a manhole, the first thing you should do is?
    1. Test the air inside the manhole with a gas meter
    2. Put on a self contained breathing apparatus
    3. Fill in a confined space entry permit
    4. Call the fire department
  10. Convert 3.9 million gallons per day to cublic feet per minute
    1. 0.52 cfm
    2. 362 cfm
    3. 2762 cfm
    4. 21,724 cfm