(Part 2) grade 4 wastewater operator |\ |\ |\ |\ |\ |\
certification practice test QUESTIONS |\ |\ |\ |\
WITH ANSWERS |\
In the enhanced-biological-nutrient-control activated sludge
|\ |\ |\ |\ |\
system for the process control of phosphorus removal, what are
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\
the primary controlling variables for the desired microbial
|\ |\ |\ |\ |\ |\ |\ |\
population? |\
a. volatile fatty acids b. soluble BOD5 and phosphate c. pH and
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
alkalinity d. oxidized nitrogen and DO - CORRECT ANSWERS ✔✔d.
|\ |\ |\ |\ |\ |\ |\ |\ |\
oxidized nitrogen and DO
|\ |\ |\ |\
In the four-stage Bardenpho process, ammonia from the influent
|\ |\ |\ |\ |\ |\ |\ |\ |\
is converted to nitrate in which area?
|\ |\ |\ |\ |\ |\ |\
a. anoxic zone b. aeration basin c. anaerobic zone d. aerobic
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
zone - CORRECT ANSWERS ✔✔b. aeration basin
|\ |\ |\ |\ |\ |\
. What is the theoretical amount of oxygen in milligrams required
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\
to convert 1 mg of ammonia nitrogen to nitrate nitrogen?
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
a. 2.5 mg b. 3.3 mg c. 4.6 mg d. 7.1 mg - CORRECT ANSWERS
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
✔✔c. 4.6 mg |\ |\
,What is the operating guideline in the four-stage Bardenpho
|\ |\ |\ |\ |\ |\ |\ |\ |\
process for the mean cell residence time?|\ |\ |\ |\ |\ |\
a. 15 to 20 days b. 20 to 25 days c. 20 to 30 days d. 20 to 40
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
days - CORRECT ANSWERS ✔✔c. 20 to 30 days
|\ |\ |\ |\ |\ |\ |\ |\
The optimum pH range in the enhanced chemical nutrient control
|\ |\ |\ |\ |\ |\ |\ |\ |\
reactions for phosphorus removed by Fe3+ addition is
|\ |\ |\ |\ |\ |\ |\ |\
a. 4.0 to 6.0 b. 4.5 to 6.0 c. 4.5 to 6.5 d. 5.0 to 6.5 - CORRECT
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔a. 4.0 to 6.0 |\ |\ |\ |\
What is the desired DO level for an anaerobic selector?
|\ |\ |\ |\ |\ |\ |\ |\ |\
a. 0.05 mg/L b. 0.10 mg/L c. 0.15 mg/L d. 0.20 mg/L - CORRECT
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔b. 0.10 mg/L |\ |\ |\
Which one of the following types of foam is the most persistent
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
and most difficult to control?
|\ |\ |\ |\
a. solids from the dewatering process b. filamentous or Nocardia
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\
organisms c. polymer overdosing d. nutrient deficiencies -
|\ |\ |\ |\ |\ |\ |\ |\ |\
CORRECT ANSWERS ✔✔b. filamentous or Nocardia organisms
|\ |\ |\ |\ |\ |\
In the reaction of hydrogen sulfide with chlorine to form sulfuric
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
acid, it takes one part hydrogen sulfide for every _______ parts of
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
chlorine.
, |\ a. 2.5 b. 4.5 c. 6.5 d. 8.5 - CORRECT ANSWERS ✔✔d. 8.5
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
. Dichloramine will be present in wastewaters at pH values below
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
what? |\
a. 5.5 b. 5.0 c. 4.7 d. 4.3 - CORRECT ANSWERS ✔✔a. 5.5
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
What is the recommended withdrawal of chlorine from a 100- or
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
150-lb cylinder for each degree Fahrenheit ambient temperature
|\ |\ |\ |\ |\ |\ |\ |\
such that freezing does not occur?
|\ |\ |\ |\ |\
|\ a. 1 lb b. 2 lb c. 3 lb d. 4 lb - CORRECT ANSWERS ✔✔a. 1 lb
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
What chlorine emergency repair kit is used to stop leaks only at
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
the valves of tank cars? |\ |\ |\ |\
a. emergency repair kit A b. emergency repair kit B c.
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
emergency repair kit C d. emergency repair kit T - CORRECT |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔c. emergency repair kit C |\ |\ |\ |\ |\
If a liquid sulfonator was misting, what would most likely be the
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
cause?
a. loss of water pressure b. wrong size injector valve c. dirty
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
injector valve d. defective evaporator - CORRECT ANSWERS ✔✔d.
|\ |\ |\ |\ |\ |\ |\ |\
defective evaporator
|\ |\
certification practice test QUESTIONS |\ |\ |\ |\
WITH ANSWERS |\
In the enhanced-biological-nutrient-control activated sludge
|\ |\ |\ |\ |\
system for the process control of phosphorus removal, what are
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\
the primary controlling variables for the desired microbial
|\ |\ |\ |\ |\ |\ |\ |\
population? |\
a. volatile fatty acids b. soluble BOD5 and phosphate c. pH and
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
alkalinity d. oxidized nitrogen and DO - CORRECT ANSWERS ✔✔d.
|\ |\ |\ |\ |\ |\ |\ |\ |\
oxidized nitrogen and DO
|\ |\ |\ |\
In the four-stage Bardenpho process, ammonia from the influent
|\ |\ |\ |\ |\ |\ |\ |\ |\
is converted to nitrate in which area?
|\ |\ |\ |\ |\ |\ |\
a. anoxic zone b. aeration basin c. anaerobic zone d. aerobic
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
zone - CORRECT ANSWERS ✔✔b. aeration basin
|\ |\ |\ |\ |\ |\
. What is the theoretical amount of oxygen in milligrams required
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\
to convert 1 mg of ammonia nitrogen to nitrate nitrogen?
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
a. 2.5 mg b. 3.3 mg c. 4.6 mg d. 7.1 mg - CORRECT ANSWERS
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
✔✔c. 4.6 mg |\ |\
,What is the operating guideline in the four-stage Bardenpho
|\ |\ |\ |\ |\ |\ |\ |\ |\
process for the mean cell residence time?|\ |\ |\ |\ |\ |\
a. 15 to 20 days b. 20 to 25 days c. 20 to 30 days d. 20 to 40
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
days - CORRECT ANSWERS ✔✔c. 20 to 30 days
|\ |\ |\ |\ |\ |\ |\ |\
The optimum pH range in the enhanced chemical nutrient control
|\ |\ |\ |\ |\ |\ |\ |\ |\
reactions for phosphorus removed by Fe3+ addition is
|\ |\ |\ |\ |\ |\ |\ |\
a. 4.0 to 6.0 b. 4.5 to 6.0 c. 4.5 to 6.5 d. 5.0 to 6.5 - CORRECT
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔a. 4.0 to 6.0 |\ |\ |\ |\
What is the desired DO level for an anaerobic selector?
|\ |\ |\ |\ |\ |\ |\ |\ |\
a. 0.05 mg/L b. 0.10 mg/L c. 0.15 mg/L d. 0.20 mg/L - CORRECT
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔b. 0.10 mg/L |\ |\ |\
Which one of the following types of foam is the most persistent
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
and most difficult to control?
|\ |\ |\ |\
a. solids from the dewatering process b. filamentous or Nocardia
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\
organisms c. polymer overdosing d. nutrient deficiencies -
|\ |\ |\ |\ |\ |\ |\ |\ |\
CORRECT ANSWERS ✔✔b. filamentous or Nocardia organisms
|\ |\ |\ |\ |\ |\
In the reaction of hydrogen sulfide with chlorine to form sulfuric
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
acid, it takes one part hydrogen sulfide for every _______ parts of
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
chlorine.
, |\ a. 2.5 b. 4.5 c. 6.5 d. 8.5 - CORRECT ANSWERS ✔✔d. 8.5
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
. Dichloramine will be present in wastewaters at pH values below
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
what? |\
a. 5.5 b. 5.0 c. 4.7 d. 4.3 - CORRECT ANSWERS ✔✔a. 5.5
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
What is the recommended withdrawal of chlorine from a 100- or
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
150-lb cylinder for each degree Fahrenheit ambient temperature
|\ |\ |\ |\ |\ |\ |\ |\
such that freezing does not occur?
|\ |\ |\ |\ |\
|\ a. 1 lb b. 2 lb c. 3 lb d. 4 lb - CORRECT ANSWERS ✔✔a. 1 lb
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
What chlorine emergency repair kit is used to stop leaks only at
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
the valves of tank cars? |\ |\ |\ |\
a. emergency repair kit A b. emergency repair kit B c.
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
emergency repair kit C d. emergency repair kit T - CORRECT |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔c. emergency repair kit C |\ |\ |\ |\ |\
If a liquid sulfonator was misting, what would most likely be the
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
cause?
a. loss of water pressure b. wrong size injector valve c. dirty
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
injector valve d. defective evaporator - CORRECT ANSWERS ✔✔d.
|\ |\ |\ |\ |\ |\ |\ |\
defective evaporator
|\ |\
