TEXAS CLASS D WATER LICENSE
EXAM 2025 QUESTIONS AND ANSWERS
What removes tastes, odors, and certain organics and gases, and oxidizes iron and manganese?
This process includes the incorporation of air into the water by means of spray nozzles , steps
or cascades, or trays of diffusers? - ANS Aeration
TCEQ regulation states that Shore installations , marinas, boats and houses on the watershed
must have sewage? - ANS disposal
Water aerated or chlorinated at proper pH levels oxidizes the iron and manganese, turning
them into solid? - ANS particles
Well casing and cementing protect the well from collapse and surface ? - ANS contamination
Sequestering does not remove iron from the water, but prevents it from combining with oxygen
and? - ANS reddening
The quantity of water a formation yields depends on the formations thickness and? -
ANS permeability
Cascade aerators, packed air-stripping towers, and air diffusers are used to aerate? -
ANS water
Aeration can be used to remove what from the water supply? - ANS iron and manganese
Hydrogen sulfide has a rotten egg odor and is oxidized by? - ANS super-chlorination
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,When Iron levels get this high, it can cause red stains on clothing, colored water, or turbidity? -
ANS 0.3 mg/L
Excess Manganese can cause? - ANS black stains
Another method of iron control is the use of? - ANS sequestering agents
What is a sequestering agent? - ANS polyphosphates
Well water is sometimes? - ANS corrosive
Low ph, dissolved gases, high temperatures, and high mineral levels can cause well water to
be? - ANS corrosive
What is the process of removing calcium and magnesium by adding lime or by exchanging ions?
- ANS softening
An ion exchange replaces calcium ions with? - ANS sodium ions
A process available for removing arsenic, fluoride, lead, mercury, nitrate, and silver from raw
water is? - ANS coagulation followed by sedimentation and filtration
A process that forces water through a membrane is? - ANS reverse osmosis
In reverse osmosis a sheet of synthetic material (membrane) under pressure prevents passage
of dissolved materials and larger particles and ejects them in a? - ANS waste stream
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, The Surface Water Treatment Rule (SWTR) requires community and non-community wells,
springs, and infiltration galleries ( a subsurface tunnel that collects groundwater) to determine
possible direct influence of? - ANS surface water
Changes in groundwater quality can indicate influence of surface water organisms such as
giardia cysts, algae or other? - ANS microorganisms
If well is deeper than 50 feet and more than 200 feet from a nearby surface water body,
extensive evaluation of the influence of surface water on a water supply is? - ANS not
required
Surface water evaluations are needed on a water supply when shifts in water quality occur such
as turbidity, temperature, pH, and the presence of? - ANS surface water organisms
What are underground, water-bearing formations yielding useful quantities of water? -
ANS Aquifiers
Problems caused by what are declining water levels and subsidence (sinking of land)? -
ANS overpumping
The purpose of the well screen is to keep out birds and? - ANS sand
the most important feature of the well screen is the size of the? - ANS opening
The mesh size of the screen is determined by the size of the aquifer material, the size of the
gravel in the gravel pack, and the type of well ? - ANS development
The gravel pack is fine gravel placed around the screen to reduce pumping? - ANS sand
The well vent is a vacuum breaker allowing the casing to breathe as water levels change when
the pump? - ANS cycles
COPYRIGHT © 2025 THESTAR ALL RIGHTS RESERVED 3
EXAM 2025 QUESTIONS AND ANSWERS
What removes tastes, odors, and certain organics and gases, and oxidizes iron and manganese?
This process includes the incorporation of air into the water by means of spray nozzles , steps
or cascades, or trays of diffusers? - ANS Aeration
TCEQ regulation states that Shore installations , marinas, boats and houses on the watershed
must have sewage? - ANS disposal
Water aerated or chlorinated at proper pH levels oxidizes the iron and manganese, turning
them into solid? - ANS particles
Well casing and cementing protect the well from collapse and surface ? - ANS contamination
Sequestering does not remove iron from the water, but prevents it from combining with oxygen
and? - ANS reddening
The quantity of water a formation yields depends on the formations thickness and? -
ANS permeability
Cascade aerators, packed air-stripping towers, and air diffusers are used to aerate? -
ANS water
Aeration can be used to remove what from the water supply? - ANS iron and manganese
Hydrogen sulfide has a rotten egg odor and is oxidized by? - ANS super-chlorination
COPYRIGHT © 2025 THESTAR ALL RIGHTS RESERVED 1
,When Iron levels get this high, it can cause red stains on clothing, colored water, or turbidity? -
ANS 0.3 mg/L
Excess Manganese can cause? - ANS black stains
Another method of iron control is the use of? - ANS sequestering agents
What is a sequestering agent? - ANS polyphosphates
Well water is sometimes? - ANS corrosive
Low ph, dissolved gases, high temperatures, and high mineral levels can cause well water to
be? - ANS corrosive
What is the process of removing calcium and magnesium by adding lime or by exchanging ions?
- ANS softening
An ion exchange replaces calcium ions with? - ANS sodium ions
A process available for removing arsenic, fluoride, lead, mercury, nitrate, and silver from raw
water is? - ANS coagulation followed by sedimentation and filtration
A process that forces water through a membrane is? - ANS reverse osmosis
In reverse osmosis a sheet of synthetic material (membrane) under pressure prevents passage
of dissolved materials and larger particles and ejects them in a? - ANS waste stream
COPYRIGHT © 2025 THESTAR ALL RIGHTS RESERVED 2
, The Surface Water Treatment Rule (SWTR) requires community and non-community wells,
springs, and infiltration galleries ( a subsurface tunnel that collects groundwater) to determine
possible direct influence of? - ANS surface water
Changes in groundwater quality can indicate influence of surface water organisms such as
giardia cysts, algae or other? - ANS microorganisms
If well is deeper than 50 feet and more than 200 feet from a nearby surface water body,
extensive evaluation of the influence of surface water on a water supply is? - ANS not
required
Surface water evaluations are needed on a water supply when shifts in water quality occur such
as turbidity, temperature, pH, and the presence of? - ANS surface water organisms
What are underground, water-bearing formations yielding useful quantities of water? -
ANS Aquifiers
Problems caused by what are declining water levels and subsidence (sinking of land)? -
ANS overpumping
The purpose of the well screen is to keep out birds and? - ANS sand
the most important feature of the well screen is the size of the? - ANS opening
The mesh size of the screen is determined by the size of the aquifer material, the size of the
gravel in the gravel pack, and the type of well ? - ANS development
The gravel pack is fine gravel placed around the screen to reduce pumping? - ANS sand
The well vent is a vacuum breaker allowing the casing to breathe as water levels change when
the pump? - ANS cycles
COPYRIGHT © 2025 THESTAR ALL RIGHTS RESERVED 3
