#2) Questions With 100% Correct
Answers
What is a pathogen? - ANS ✔ - Disease-causing microorganism
What is the impact of algae to water quality? - ANS ✔ - taste and odor problems
What is the concentration of chlorine gas? - ANS ✔ - 100%
Which of the following is not used to mix coagulants? - ANS ✔ - Horizontal paddle wheel.
What is considered to be a quick remedy to address a sudden increase in filtered water turbidity? -
ANS ✔ - Feed a filter-aid chemical to the filter influent.
What is the likely cause of a pinging noise in a pump? - ANS ✔ - cavitation
Which of the following controls the efficiency of removing suspended solids in the sedimentation
process? - ANS ✔ - Flowrate
What is a sanitary survey? - ANS ✔ - An analysis to determine all potential water quality impacts to a
proposed well
Which of the following categories does bacteria belong to? - ANS ✔ - Colloidal
Under the surface water treatment rule, what must the reduction of viruses be through filtration and
disinfection? - ANS ✔ - 99.99%
, Water Treatment Class D (practice exam
#2) Questions With 100% Correct
Answers
Which of the following is not considered free residual chlorine? - ANS ✔ - Monochloramine
Why is coliform used as an indicator organism - ANS ✔ - it reduces the complexity and cost of analysis
What is an example of a non-community, non-transient water system? - ANS ✔ - school
What is the purpose of a packing in a pump? - ANS ✔ - Control the leakage of water along the pump
shaft and prevent air from entering along the shaft when the pump is in a suction lift condition
What does the addition of carbon dioxide do to the pH of water? - ANS ✔ - Lowers it
What is an unconfined aquifer? - ANS ✔ - One in which groundwater possesses a free surface open to
the atmosphere
What is the static water level in a well? - ANS ✔ - Water level when pump is not running.
Which of the following will least likely impact the formation of flocs during the coagulation and
flocculation process? - ANS ✔ - hardness
What is formed when free chlorine reacts with ammonia? - ANS ✔ - Chloramine
Which contaminant causes blue baby syndrome? - ANS ✔ - Nitrate
What is free chlorine? - ANS ✔ - The concentration of residual chlorine in water which is present as
dissolved gas (CL2), hypochlorous acid (HOCI), and/or hypochlorite ion (OCI).