A Exam Practice Questions And Correct

Groundwater Treatment Operator Class A Exam Practice Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• What is the primary purpose of aeration in groundwater treatment?
• Disinfect water
• Remove dissolved gases and volatile compounds
• Increase water hardness
• Remove suspended solids

Rationale: Aeration introduces air to the water, removing dissolved

gases like hydrogen sulfide and volatile compounds such as radon.

• Which type of pump is most commonly used for high-pressure

groundwater wells?

• Centrifugal pump 1 / 4

• Vertical turbine pump
• Reciprocating pump
• Diaphragm pump

Rationale: Vertical turbine pumps are ideal for deep wells because

they can efficiently lift water from great depths.

3. The term “drawdown” in a well refers to:

• The rise in water level
• The difference between static and pumping water levels
• Pump efficiency
• Well casing diameter

Rationale: Drawdown is the drop in water level when a well is being

pumped compared to its static level.

• The main disadvantage of using chlorine for groundwater disinfection

is:

• It does not kill bacteria
• Formation of disinfection byproducts
• Expensive equipment
• Slow acting

Rationale: Chlorine reacts with organic matter in water, forming

potentially harmful byproducts like THMs and HAAs.

• Which of the following is a common groundwater contaminant

requiring oxidation?

• Nitrate 2 / 4

• Iron
• Fluoride
• Hardness

Rationale: Iron in groundwater is typically oxidized to form insoluble

ferric hydroxide, which can be filtered out.

• What is the main purpose of a settling basin in groundwater

treatment?

• To disinfect water
• To remove suspended solids by sedimentation
• To soften water
• To adjust pH

Rationale: Settling basins allow heavier particles to settle, reducing

turbidity before further treatment.

• Which parameter is critical to monitor in a chemical feed system for

groundwater treatment?

• Turbidity
• pH
• Chemical dose rate
• Flow rate only

Rationale: Maintaining the correct chemical dose ensures effective

treatment and prevents overdosing or underdosing.

8. Ion exchange is primarily used in groundwater treatment to:

• Remove microbes 3 / 4

• Remove hardness ions
• Remove suspended solids
• Adjust pH

Rationale: Ion exchange removes calcium and magnesium ions,

softening the water.

9. The most common coagulant used in groundwater treatment is:

• Sodium hydroxide
• Aluminum sulfate (alum)
• Sodium hypochlorite
• Calcium carbonate

Rationale: Alum destabilizes suspended particles, promoting floc

formation for sedimentation or filtration.

• When adjusting pH in groundwater treatment, which chemical is

commonly used to increase pH?

• Hydrochloric acid
• Lime (Ca(OH)₂)
• Sulfuric acid
• Chlorine

Rationale: Lime is added to raise pH, which can help with softening

and iron removal.

• The primary purpose of a greensand filter in groundwater

treatment is to:

• Remove turbidity
• / 4