NGWA Well Servicing and Maintenance
Certification Exam (Exam N) – Practice
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. What is the primary purpose of a well maintenance program?
A. Increase water temperature
B. Ensure well efficiency and longevity
C. Reduce groundwater levels
D. Install new pumps
Rationale: Regular maintenance helps maintain the well’s
performance and extends its service life.
2. How often should a typical water well be inspected for routine
maintenance?
A. Every month
, B. Every 10 years
C. Annually
D. Only when failure occurs
Rationale: Annual inspections allow for early detection of issues
before they become serious.
3. Which of the following is a common cause of reduced well yield?
A. High water demand
B. Sediment buildup in the well screen
C. Using a larger pump
D. Installing a chlorinator
Rationale: Sediment or mineral buildup can restrict water flow and
reduce yield.
4. What is the recommended action if a well shows signs of bacterial
contamination?
A. Reduce pumping
B. Shock chlorination of the well
C. Increase water usage
D. Install a pressure tank
Rationale: Shock chlorination disinfects the well and eliminates
bacteria.
5. Which tool is commonly used to measure pump performance in a
well?
A. Multimeter
, B. Flow meter
C. Tape measure
D. Thermometer
Rationale: A flow meter measures water output to assess pump
efficiency.
6. Why is it important to maintain proper pump alignment?
A. Reduces water hardness
B. Prevents premature mechanical wear
C. Increases well depth
D. Cleans the well screen
Rationale: Misalignment can cause vibration, friction, and early
pump failure.
7. What is the main risk of a dry well during pumping?
A. Reduced sediment
B. Lower water temperature
C. Pump damage due to cavitation
D. Increased water hardness
Rationale: Pumping without water can cause cavitation, damaging
pump components.
8. Which chemical is commonly used for well disinfection?
A. Ammonia
B. Chlorine
C. Sodium bicarbonate
, D. Hydrogen peroxide
Rationale: Chlorine is widely used for disinfecting wells and
eliminating pathogens.
9. What is the primary purpose of a well screen?
A. Increase flow velocity
B. Prevent sediment from entering the pump
C. Lower water pH
D. Reduce water temperature
Rationale: Well screens filter out sand and debris while allowing
water to enter the well.
10. Which sign indicates a potential pump motor problem?
A. Clear water
B. Unusual noise or vibration
C. Normal water flow
D. Stable water temperature
Rationale: Abnormal noises or vibration often indicate mechanical or
electrical issues in the pump.
11. What is the recommended action if a well pump loses prime?
A. Pump faster
B. Check for air leaks in suction line
C. Install a new well
D. Reduce water usage
Certification Exam (Exam N) – Practice
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. What is the primary purpose of a well maintenance program?
A. Increase water temperature
B. Ensure well efficiency and longevity
C. Reduce groundwater levels
D. Install new pumps
Rationale: Regular maintenance helps maintain the well’s
performance and extends its service life.
2. How often should a typical water well be inspected for routine
maintenance?
A. Every month
, B. Every 10 years
C. Annually
D. Only when failure occurs
Rationale: Annual inspections allow for early detection of issues
before they become serious.
3. Which of the following is a common cause of reduced well yield?
A. High water demand
B. Sediment buildup in the well screen
C. Using a larger pump
D. Installing a chlorinator
Rationale: Sediment or mineral buildup can restrict water flow and
reduce yield.
4. What is the recommended action if a well shows signs of bacterial
contamination?
A. Reduce pumping
B. Shock chlorination of the well
C. Increase water usage
D. Install a pressure tank
Rationale: Shock chlorination disinfects the well and eliminates
bacteria.
5. Which tool is commonly used to measure pump performance in a
well?
A. Multimeter
, B. Flow meter
C. Tape measure
D. Thermometer
Rationale: A flow meter measures water output to assess pump
efficiency.
6. Why is it important to maintain proper pump alignment?
A. Reduces water hardness
B. Prevents premature mechanical wear
C. Increases well depth
D. Cleans the well screen
Rationale: Misalignment can cause vibration, friction, and early
pump failure.
7. What is the main risk of a dry well during pumping?
A. Reduced sediment
B. Lower water temperature
C. Pump damage due to cavitation
D. Increased water hardness
Rationale: Pumping without water can cause cavitation, damaging
pump components.
8. Which chemical is commonly used for well disinfection?
A. Ammonia
B. Chlorine
C. Sodium bicarbonate
, D. Hydrogen peroxide
Rationale: Chlorine is widely used for disinfecting wells and
eliminating pathogens.
9. What is the primary purpose of a well screen?
A. Increase flow velocity
B. Prevent sediment from entering the pump
C. Lower water pH
D. Reduce water temperature
Rationale: Well screens filter out sand and debris while allowing
water to enter the well.
10. Which sign indicates a potential pump motor problem?
A. Clear water
B. Unusual noise or vibration
C. Normal water flow
D. Stable water temperature
Rationale: Abnormal noises or vibration often indicate mechanical or
electrical issues in the pump.
11. What is the recommended action if a well pump loses prime?
A. Pump faster
B. Check for air leaks in suction line
C. Install a new well
D. Reduce water usage
