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1. Which two categories best describe loading rates?

   1.   ?    Influent and hydraulic loading
   2.   ?    Hydraulic and effluent
   3.   ?    Organic and mixed liquor
   4.   ?    Hydraulic and organic

2. What is the result of the formula π r² x Depth?

   1.   ?    Cubic feet
   2.   ?    Gallons
   3.   ?    Square feet
   4.   ?    Detention time

3. What is the main difference between SRT and MCRT?

   1.   ?    Influent CBOD₅
   2.   ?    The RAS rate
   3.   ?    Total solids vs. volatile solids
   4.   ?    Detention time

4. Which loading rate is associated with all of the following: tank volume and capacity (cubic feet and gal), detention time (hours), surface settling rate (gpd/ft²) and weir overflow rate (gpd/ft of weir length)?

   1.   ?    Organic
   2.   ?    Solids
   3.   ?    Aerations system
   4.   ?    Hydraulic

5. What does the following formula represent?
   
   Flow, gallons/day ÷ Surface Area, sq.ft.

   1.   ?    Weir overflow rate
   2.   ?    Solids loading rate
   3.   ?    Surface settling rate
   4.   ?    F/M ratio

6. If a plant had 75,000 pounds of MLSS in inventory, and desired to maintain a 7 day SRT, how many pounds/day of solids must be wasted from the system?

   1.   ?    7,500 lbs/day
   2.   ?    10,714 lbs/day
   3.   ?    9,333 lbs/day
   4.   ?    75,000 lbs/day

7. What does this formula best describe?
   
   27,022 lbs/day ÷ 7,250 ppm x 8.34 lbs/gal
   
   

   1.   ?    Pounds of solids to waste
   2.   ?    Concentration of sludge to waste
   3.   ?    mgd of sludge to waste
   4.   ?    gpm of sludge to waste

8. Typically, when an aeration tank is over-aerated, or overloaded (high F/M … low MLSS), what color will the foam be?

   1.   ?    Dark black
   2.   ?    Tan and greasy
   3.   ?    Stiff and white
   4.   ?    Orange

9. What type of floc is typically the result, and/or results in, the following characteristics: high F/M ratio, high food supply, young sludge, log growth phase, slow settling mixed liquor with excellent capture and clear effluent?

   1.   ?    Pin
   2.   ?    Biodeflocculation
   3.   ?    Straggler
   4.   ?    Rotifers

10. Which RAS condition may indicate the need to increase the aeration process D.O.?

    1.   ?    High nitrates in the RAS
    2.   ?    Strong odors in the RAS
    3.   ?    Pin floc in the RAS
    4.   ?    Low solids concentration in the RAS