NGWA FINAL PAPER 2026 FULL
QUESTIONS AND CORRECT ANSWERS
◉ How do you determine the static water pressure?
Answer: Static water pressure is determined by measuring the
height of the water column above the point of measurement in the
well. It is calculated using the formula.
Pressure (psi) = Height of water column (ft) × 0.433.
◉ Define aquifer.
Answer: An aquifer is a geological formation of permeable rock,
sand, or gravel that can store and transmit groundwater, providing a
source of water for wells and springs.
◉ What is an artesian well?
Answer: An artesian well is a type of well where groundwater is
under pressure, causing water to rise to the surface naturally
without the need for pumping. This occurs when the well taps into a
confined aquifer.
◉ What is the difference between confined and unconfined aquifers?
,Answer: A confined aquifer is trapped between two impermeable
layers of rock or clay, creating pressure that can cause water to rise
in a well.
An unconfined aquifer has no confining layer above it, so its water
level is influenced directly by the surface and atmospheric pressure.
◉ Permeability refers to what quality in a water bearing formation?
Answer: Permeability refers to the ability of a water-bearing
formation to transmit water through its pores or fractures, allowing
groundwater to flow through the material.
◉ How fast does ground water move in the following formation?
- Sand and gravel?
- Sandstone?
- Non-porous rock?
Answer: Sand and Gravel: Groundwater moves relatively quickly,
typically ranging from 1 to 100 feet per day.
Sandstone: Groundwater moves more slowly, usually between 0.01
to 1 foot per day.
Non-Porous Rock: Groundwater movement is extremely slow or
negligible, often less than 0.001 feet per day.
, ◉ Explain how ground water formations could be recharged. Define
infiltration.
Answer: Groundwater formations are recharged through the process
of precipitation, where rain or snowmelt infiltrates the ground,
moving through the soil and permeable layers until it reaches the
water table. Recharge can also occur from surface water bodies like
rivers, lakes, or artificial recharge methods.
Infiltration is the process by which water on the surface enters the
soil and moves downward into the subsurface, contributing to
groundwater recharge.
◉ How is precipitation measured? What amount of precipitation
becomes ground water?
Answer: Precipitation is measured using devices like rain gauges,
which collect and measure the amount of rain, snow, or other forms
of moisture over a set period. The amount of precipitation that
becomes groundwater varies but is typically around 10% to 20%,
depending on factors such as soil type, vegetation, slope, and climate
conditions.
◉ How can you determine the storage measure of aquifers?
Answer: The storage measure of aquifers is determined by
calculating the specific yield (the volume of water that drains from
the aquifer under gravity) and the specific retention (the volume of
QUESTIONS AND CORRECT ANSWERS
◉ How do you determine the static water pressure?
Answer: Static water pressure is determined by measuring the
height of the water column above the point of measurement in the
well. It is calculated using the formula.
Pressure (psi) = Height of water column (ft) × 0.433.
◉ Define aquifer.
Answer: An aquifer is a geological formation of permeable rock,
sand, or gravel that can store and transmit groundwater, providing a
source of water for wells and springs.
◉ What is an artesian well?
Answer: An artesian well is a type of well where groundwater is
under pressure, causing water to rise to the surface naturally
without the need for pumping. This occurs when the well taps into a
confined aquifer.
◉ What is the difference between confined and unconfined aquifers?
,Answer: A confined aquifer is trapped between two impermeable
layers of rock or clay, creating pressure that can cause water to rise
in a well.
An unconfined aquifer has no confining layer above it, so its water
level is influenced directly by the surface and atmospheric pressure.
◉ Permeability refers to what quality in a water bearing formation?
Answer: Permeability refers to the ability of a water-bearing
formation to transmit water through its pores or fractures, allowing
groundwater to flow through the material.
◉ How fast does ground water move in the following formation?
- Sand and gravel?
- Sandstone?
- Non-porous rock?
Answer: Sand and Gravel: Groundwater moves relatively quickly,
typically ranging from 1 to 100 feet per day.
Sandstone: Groundwater moves more slowly, usually between 0.01
to 1 foot per day.
Non-Porous Rock: Groundwater movement is extremely slow or
negligible, often less than 0.001 feet per day.
, ◉ Explain how ground water formations could be recharged. Define
infiltration.
Answer: Groundwater formations are recharged through the process
of precipitation, where rain or snowmelt infiltrates the ground,
moving through the soil and permeable layers until it reaches the
water table. Recharge can also occur from surface water bodies like
rivers, lakes, or artificial recharge methods.
Infiltration is the process by which water on the surface enters the
soil and moves downward into the subsurface, contributing to
groundwater recharge.
◉ How is precipitation measured? What amount of precipitation
becomes ground water?
Answer: Precipitation is measured using devices like rain gauges,
which collect and measure the amount of rain, snow, or other forms
of moisture over a set period. The amount of precipitation that
becomes groundwater varies but is typically around 10% to 20%,
depending on factors such as soil type, vegetation, slope, and climate
conditions.
◉ How can you determine the storage measure of aquifers?
Answer: The storage measure of aquifers is determined by
calculating the specific yield (the volume of water that drains from
the aquifer under gravity) and the specific retention (the volume of
