NGWA Exam Prep 2026 | 154 Questions & Answers |
Certification Study Guide
1. Describe the significance of aquifers in the context of water well drilling.
Aquifers only affect water quality, not extraction.
Aquifers are not relevant to water well drilling.
Aquifers are primarily used for surface water storage.
Aquifers are crucial for sustainable water extraction as they provide
a reliable source of groundwater.
2. What is the primary reason for conducting well maintenance?
To increase the depth of the well.
To ensure the longevity of the well and the safety of the
groundwater being extracted.
To enhance the drilling speed.
To reduce the cost of water extraction.
3. What is the primary function of the drill string in water well drilling?
Filters impurities from the water
Holds the well casing in place
Transmits fluid and/or rotational power
Measures the depth of the well
4. If a new drilling site is found to have low porosity, what implications might this
have for groundwater extraction?
, Groundwater extraction will be faster because of lower resistance to
flow.
Groundwater extraction will be unaffected by the porosity of the
material.
Low porosity indicates that the site is ideal for drilling and extraction.
Groundwater extraction may be slower and less efficient due to the
low porosity of the material.
5. Describe the significance of groundwater discharge regions in relation to
surface water bodies.
Groundwater discharge regions prevent surface water from entering
aquifers.
Groundwater discharge regions are locations where water is filtered
for drinking.
Groundwater discharge regions are areas where water evaporates
into the atmosphere.
Groundwater discharge regions contribute to the flow of rivers and
lakes by releasing groundwater.
6. What is the primary purpose of drilling fluids in rotary drilling?
To provide structural support to the well.
To filter groundwater before extraction.
To carry cuttings and perform various downhole functions.
To cool the drill bit only.
7. Which of the following best describes a geologic map?
A map that shows the elevation of the earth's surface.
, A map that uses contours to show the elevation of the top of a
sedimentary rock layer.
A map that shows the location of all the wells that have been drilled in
an area.
A map that shows where each rock layer crops out on the surface of
the earth.
8. The discharge per unit drawdown at the well is known as:
Specific capacity
Specific retention
Specific storage
Specific yield
9. What is the primary purpose of groundwater extraction?
To recharge aquifers with surface water.
To filter contaminants from surface water.
To remove water from underground aquifers for use.
To measure the water table level.
10. What is one important quality of an aquifer?
E. All of these answer choices are important qualities of aquifers.
B. The water supply is replenished through infiltration of rain and
snowmelt.
D. Individual homes can access the water supply by digging wells into
the aquifer.
, A. Bacteria and other contaminants are filtered out of the water by
rocks and soil.
C. It is a source of potable water.
11. What occurs to the groundwater table when water is withdrawn from a well?
The aquifer expands.
A cone of depression forms.
The well becomes contaminated.
The water table rises.
12. What is the primary purpose of a water well?
To store surface water
To provide irrigation
To extract groundwater
To monitor soil quality
13. What type of chlorine product is used most often to disinfect groundwater
wells?
Chloramines
Total chlorine
Gas chlorine
Hypochlorites
14. What is the definition of drawdown in the context of water wells?
The lowering of the water surface in a well due to water discharge.
Certification Study Guide
1. Describe the significance of aquifers in the context of water well drilling.
Aquifers only affect water quality, not extraction.
Aquifers are not relevant to water well drilling.
Aquifers are primarily used for surface water storage.
Aquifers are crucial for sustainable water extraction as they provide
a reliable source of groundwater.
2. What is the primary reason for conducting well maintenance?
To increase the depth of the well.
To ensure the longevity of the well and the safety of the
groundwater being extracted.
To enhance the drilling speed.
To reduce the cost of water extraction.
3. What is the primary function of the drill string in water well drilling?
Filters impurities from the water
Holds the well casing in place
Transmits fluid and/or rotational power
Measures the depth of the well
4. If a new drilling site is found to have low porosity, what implications might this
have for groundwater extraction?
, Groundwater extraction will be faster because of lower resistance to
flow.
Groundwater extraction will be unaffected by the porosity of the
material.
Low porosity indicates that the site is ideal for drilling and extraction.
Groundwater extraction may be slower and less efficient due to the
low porosity of the material.
5. Describe the significance of groundwater discharge regions in relation to
surface water bodies.
Groundwater discharge regions prevent surface water from entering
aquifers.
Groundwater discharge regions are locations where water is filtered
for drinking.
Groundwater discharge regions are areas where water evaporates
into the atmosphere.
Groundwater discharge regions contribute to the flow of rivers and
lakes by releasing groundwater.
6. What is the primary purpose of drilling fluids in rotary drilling?
To provide structural support to the well.
To filter groundwater before extraction.
To carry cuttings and perform various downhole functions.
To cool the drill bit only.
7. Which of the following best describes a geologic map?
A map that shows the elevation of the earth's surface.
, A map that uses contours to show the elevation of the top of a
sedimentary rock layer.
A map that shows the location of all the wells that have been drilled in
an area.
A map that shows where each rock layer crops out on the surface of
the earth.
8. The discharge per unit drawdown at the well is known as:
Specific capacity
Specific retention
Specific storage
Specific yield
9. What is the primary purpose of groundwater extraction?
To recharge aquifers with surface water.
To filter contaminants from surface water.
To remove water from underground aquifers for use.
To measure the water table level.
10. What is one important quality of an aquifer?
E. All of these answer choices are important qualities of aquifers.
B. The water supply is replenished through infiltration of rain and
snowmelt.
D. Individual homes can access the water supply by digging wells into
the aquifer.
, A. Bacteria and other contaminants are filtered out of the water by
rocks and soil.
C. It is a source of potable water.
11. What occurs to the groundwater table when water is withdrawn from a well?
The aquifer expands.
A cone of depression forms.
The well becomes contaminated.
The water table rises.
12. What is the primary purpose of a water well?
To store surface water
To provide irrigation
To extract groundwater
To monitor soil quality
13. What type of chlorine product is used most often to disinfect groundwater
wells?
Chloramines
Total chlorine
Gas chlorine
Hypochlorites
14. What is the definition of drawdown in the context of water wells?
The lowering of the water surface in a well due to water discharge.
