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Texas Class D Water License Questions and
Correct 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
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
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, 2 | Page
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
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
© 2025 All rights reserved
Texas Class D Water License Questions and
Correct 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
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
© 2025 All rights reserved
, 2 | Page
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
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
© 2025 All rights reserved
