NGWA Water Systems General
Certification Practice Exam Questions
And Correct Answers (Verified Answers)
Plus Rationales 2026 Q&A | Instant
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1. The primary purpose of a water well is to:
A. Store surface water
B. Collect stormwater runoff
C. Access groundwater from an aquifer
D. Treat wastewater
Answer: C
Wells are designed to reach underground aquifers and bring
groundwater to the surface.
2. An aquifer is best defined as:
A. A layer of clay that blocks water flow
B. A body of surface water
C. A geologic formation that stores and transmits groundwater
D. A man-made underground tank
,Answer: C
Aquifers contain permeable materials that allow groundwater to
move and be extracted.
3. Which material is most permeable for groundwater movement?
A. Clay
B. Silt
C. Sand and gravel
D. Bedrock
Answer: C
Sand and gravel have large pore spaces that allow water to flow
easily.
4. The water table refers to:
A. The deepest part of an aquifer
B. The top of the saturated zone
C. The bottom of a well
D. A surface reservoir level
Answer: B
The water table marks where soil and rock pores become fully
saturated.
5. A confined aquifer is characterized by:
A. Direct exposure to the atmosphere
B. Being under pressure between impermeable layers
, C. Shallow depth only
D. Poor water quality
Answer: B
Confined aquifers are trapped between low-permeability layers and
often produce artesian pressure.
6. Artesian conditions occur when:
A. Water must be pumped mechanically
B. Water flows naturally due to pressure
C. The well is dry
D. The aquifer is unconfined
Answer: B
Pressure in confined aquifers can force water upward without
pumping.
7. The purpose of well casing is to:
A. Increase water pressure
B. Store water
C. Prevent borehole collapse and contamination
D. Improve taste
Answer: C
Casing stabilizes the well and protects groundwater from surface
pollutants.
, 8. Common well casing materials include:
A. Copper and aluminum
B. PVC and steel
C. Wood and concrete
D. Rubber and plastic tubing
Answer: B
PVC and steel are durable and widely approved for well construction.
9. A well screen is used to:
A. Seal the top of the well
B. Filter water at the pump
C. Allow water entry while keeping sediment out
D. Measure water depth
Answer: C
Screens admit groundwater while blocking sand and gravel.
10. The annular space is the area:
A. Inside the pump
B. Between casing and borehole wall
C. At the well cap
D. Below the screen
Answer: B
This space must be properly sealed to prevent contamination.
Certification Practice Exam Questions
And Correct Answers (Verified Answers)
Plus Rationales 2026 Q&A | Instant
Download Pdf
1. The primary purpose of a water well is to:
A. Store surface water
B. Collect stormwater runoff
C. Access groundwater from an aquifer
D. Treat wastewater
Answer: C
Wells are designed to reach underground aquifers and bring
groundwater to the surface.
2. An aquifer is best defined as:
A. A layer of clay that blocks water flow
B. A body of surface water
C. A geologic formation that stores and transmits groundwater
D. A man-made underground tank
,Answer: C
Aquifers contain permeable materials that allow groundwater to
move and be extracted.
3. Which material is most permeable for groundwater movement?
A. Clay
B. Silt
C. Sand and gravel
D. Bedrock
Answer: C
Sand and gravel have large pore spaces that allow water to flow
easily.
4. The water table refers to:
A. The deepest part of an aquifer
B. The top of the saturated zone
C. The bottom of a well
D. A surface reservoir level
Answer: B
The water table marks where soil and rock pores become fully
saturated.
5. A confined aquifer is characterized by:
A. Direct exposure to the atmosphere
B. Being under pressure between impermeable layers
, C. Shallow depth only
D. Poor water quality
Answer: B
Confined aquifers are trapped between low-permeability layers and
often produce artesian pressure.
6. Artesian conditions occur when:
A. Water must be pumped mechanically
B. Water flows naturally due to pressure
C. The well is dry
D. The aquifer is unconfined
Answer: B
Pressure in confined aquifers can force water upward without
pumping.
7. The purpose of well casing is to:
A. Increase water pressure
B. Store water
C. Prevent borehole collapse and contamination
D. Improve taste
Answer: C
Casing stabilizes the well and protects groundwater from surface
pollutants.
, 8. Common well casing materials include:
A. Copper and aluminum
B. PVC and steel
C. Wood and concrete
D. Rubber and plastic tubing
Answer: B
PVC and steel are durable and widely approved for well construction.
9. A well screen is used to:
A. Seal the top of the well
B. Filter water at the pump
C. Allow water entry while keeping sediment out
D. Measure water depth
Answer: C
Screens admit groundwater while blocking sand and gravel.
10. The annular space is the area:
A. Inside the pump
B. Between casing and borehole wall
C. At the well cap
D. Below the screen
Answer: B
This space must be properly sealed to prevent contamination.
