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1. Which best describes the nitrification cycle?

   1.   ?    NO₃ is converted to NH₃
   2.   ?    NH₃ is converted to NO₂ and then to NO₃
   3.   ?    NH₃ is converted to NO₃ and then to NO₂
   4.   ?    NO₂ is converted to NH₃ and then to NO₃

2. Which group of bacteria are responsible for converting nitrite to nitrate?

   1.   ?    Facultative
   2.   ?    Nitrosomonas
   3.   ?    Nitrobacter
   4.   ?    Heterotrophic

3. Given the following data, calculate the lbs of alkalinity required for nitrification:
   
   Data:
   Flow = 26.5 mgd
   Inf TKN = 42 mg/L
   Eff NH₃ = 0.75 mg/L
   90% TKN converted to NH₃
   7.14 lbs Alkalinity consumed for each lb of NH₃ Converted

   1.   ?    8,188 lbs
   2.   ?    66,276 lbs
   3.   ?    6,795 lbs
   4.   ?    58,465 lbs

4. Which adjustment will normally improve denitrification in a conventional aeration tank?

   1.   ?    Increase the air supply
   2.   ?    Increase the D.O.
   3.   ?    Decrease the D.O.
   4.   ?    Shut off the RAS

5. Which adjustment will normally improve denitrification in a 5-stage Bardenpho process?

   1.   ?    Decrease the Internal Recycle rate
   2.   ?    Increase the D.O.
   3.   ?    Decrease the RAS
   4.   ?    Increase the Internal Recycle rate

6. Given the “Fate of Phosphorus” profile, why does TP reduce through the 1st anoxic zone?

   1.   ?    Phosphorus is still being released
   2.   ?    CBOD₅ uptake through denitrification
   3.   ?    Low aerobic conditions create Luxury P Uptake
   4.   ?    Nitrification causes TP to be absorbed

7. Given the following Ortho P data for inlet and outlet of a BNR fermentation tank, does this appear to be a problem?
   
   * Fermentation Inlet Ortho P is 7.0 mg/L
   * Fermentation Outlet Ortho P is 4.0 mg/L
   Select only one answer
   

   1.   ?    Yes: Ortho P is too low in the fermentation outlet
   2.   ?    Yes: fermentation outlet Ortho P should be 2 to 4 times the concentration of the inlet
   3.   ?    No, the fermentation tank is designed to remove phosphorus directly
   4.   ?    Both "a & b"

8. What adjustment will the VFD aerator make when ammonia values are higher than target values?

   1.   ?    Decrease the VFD speed
   2.   ?    Remain the same speed
   3.   ?    Shut-off the aerator
   4.   ?    Increase the VFD speed

9. What adjustment should be considered if ammonia leaving the aerobic zone is too high?

   1.   ?    Decreasing the oxygen input, thereby increasing denitrification, will reduce the ammonia levels
   2.   ?    Increasing the oxygen input will improve nitrification
   3.   ?    Reduce MLSS levels below 1,000 ppm
   4.   ?    Increase the internal recycle rate

10. What problems will be experienced with phosphorus removal if D.O. is present in the fermentation zone?

    1.   ?    No problems … P removal will be high
    2.   ?    P release will be high but P uptake will be low
    3.   ?    P release will be hindered and P uptake will be reduced
    4.   ?    The fermentation zone should have high D.O.