TEXAS CLASS D WATER LICENSE TEST STUDY
GUIDE 2025/2026 ACCURATE QUESTIONS AND
VERIFIED CORRECT SOLUTIONS WITH
RATIONALES || 100% GUARANTEED PASS
<RECENT VERSION>
1. Ground storage at a surface water treatment receiving the treated water is
called the? - ANSWER ✓ clear well
2. The TCEQ requires all storage tanks to have screened vents, licked hatches,
a dust-proof cover, overflows with hinged flaps, and - ANSWER ✓ entry
ports
3. Total storage capacity (elevated storage included) must be how many
gallons? - ANSWER ✓ 200
4. Storage tanks must be painted, disinfected, and maintained according to
what standards? - ANSWER ✓ AWWA
5. Coatings on storage tanks for contact with potable water must be approved
by? - ANSWER ✓ EPA
6. Each foot of a water column produces how much psi? - ANSWER ✓ 0.433
7. What is the state minimum normal operating pressure? - ANSWER ✓ 35 psi
8. Elevated storage is water stored at least how many feet above the highest
service connection? - ANSWER ✓ 80
9. A ? is a tank resting on the ground that is greater in height than diameter? -
ANSWER ✓ standpipe
,10.What kind of tank also known as (hydropneumatic tanks) are cylindrical and
horizontal to the ground. - ANSWER ✓ pressure tanks
11.Annual inspections on tanks must be inspected how often? - ANSWER ✓
yearly
12.Cathodic protection is an ? method for preventing corrosion of the interior of
metal tanks? - ANSWER ✓ electrochemical
13.The TCEQ requires distribution system pressure to never fall below ? psi. -
ANSWER ✓ 20
14.Under normal operating conditions, the distribution pressure must be at least
? psi. - ANSWER ✓ 35
15.Storage facilities ? demand on the water supply? - ANSWER ✓ equalize
16.Storage allows uniform pump rates, supplies water for fire fighting, and
provides time for ? - ANSWER ✓ disenfection
17.Ground storage at a surface water treatment plant is called a ? - ANSWER ✓
clear well
18.The TCEQ requires storage tanks to have covered vents, locked hatches, a
dust-proof cover, overflows with hinged flaps, and ? - ANSWER ✓ entry
ports
19.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? -
ANSWER ✓ Aeration
20.TCEQ regulation states that Shore installations , marinas, boats and houses
on the watershed must have sewage? - ANSWER ✓ disposal
21.Water aerated or chlorinated at proper pH levels oxidizes the iron and
manganese, turning them into solid? - ANSWER ✓ particles
,22.Well casing and cementing protect the well from collapse and surface ? -
ANSWER ✓ contamination
23.Sequestering does not remove iron from the water, but prevents it from
combining with oxygen and? - ANSWER ✓ reddening
24.The quantity of water a formation yields depends on the formations
thickness and? - ANSWER ✓ permeability
25.Cascade aerators, packed air-stripping towers, and air diffusers are used to
aerate? - ANSWER ✓ water
26.Aeration can be used to remove what from the water supply? - ANSWER ✓
iron and manganese
27.Hydrogen sulfide has a rotten egg odor and is oxidized by? - ANSWER ✓
super-chlorination
28.When Iron levels get this high, it can cause red stains on clothing, colored
water, or turbidity? - ANSWER ✓ 0.3 mg/L
29.Excess Manganese can cause? - ANSWER ✓ black stains
30.Another method of iron control is the use of? - ANSWER ✓ sequestering
agents
31.What is a sequestering agent? - ANSWER ✓ polyphosphates
32.Well water is sometimes? - ANSWER ✓ corrosive
33.Low ph, dissolved gases, high temperatures, and high mineral levels can
cause well water to be? - ANSWER ✓ corrosive
34.What is the process of removing calcium and magnesium by adding lime or
by exchanging ions? - ANSWER ✓ softening
35.An ion exchange replaces calcium ions with? - ANSWER ✓ sodium ions
, 36.A process available for removing arsenic, fluoride, lead, mercury, nitrate,
and silver from raw water is? - ANSWER ✓ coagulation followed by
sedimentation and filtration
37.A process that forces water through a membrane is? - ANSWER ✓ reverse
osmosis
38.In reverse osmosis a sheet of synthetic material (membrane) under pressure
prevents passage of dissolved materials and larger particles and ejects them
in a? - ANSWER ✓ waste stream
39.If a ladder is used, it must extend at least ________ feet above the edge of
the excavation and be within ________ feet laterally of anyone in the
excavation. - ANSWER ✓ 3 feet above
25 feet laterally
40.Excavation spoil must be kept at least ________ feet from the excavation. -
ANSWER ✓ 2 feet
41.Water utility employees have a right to product information under the
________. - ANSWER ✓ Texas Hazard Communication Act
42.One of the components of the Texas Hazard Communication Act is
employee access to ________. - ANSWER ✓ SDS (formerly MSDS)
43.To prevent work area accidents, workers should be trained from the Texas
Manual on Uniform Traffic Control Devices, ________, Austin. - ANSWER
✓ Texas Department of Transportation
44.A system's filtered water must be ____ Nephelometric Turbidity Units
(NTU) or less in at least _____% of the measurements taken each month,
and no sample can exceed _____ NTU. - ANSWER ✓ 0.3 NTUs
95%
1 NTU
45.For chemical analysis, surface supplies are sampled ______ a year and
groundwater is normally sampled every ______ years. - ANSWER ✓ 1 time
3 years
GUIDE 2025/2026 ACCURATE QUESTIONS AND
VERIFIED CORRECT SOLUTIONS WITH
RATIONALES || 100% GUARANTEED PASS
<RECENT VERSION>
1. Ground storage at a surface water treatment receiving the treated water is
called the? - ANSWER ✓ clear well
2. The TCEQ requires all storage tanks to have screened vents, licked hatches,
a dust-proof cover, overflows with hinged flaps, and - ANSWER ✓ entry
ports
3. Total storage capacity (elevated storage included) must be how many
gallons? - ANSWER ✓ 200
4. Storage tanks must be painted, disinfected, and maintained according to
what standards? - ANSWER ✓ AWWA
5. Coatings on storage tanks for contact with potable water must be approved
by? - ANSWER ✓ EPA
6. Each foot of a water column produces how much psi? - ANSWER ✓ 0.433
7. What is the state minimum normal operating pressure? - ANSWER ✓ 35 psi
8. Elevated storage is water stored at least how many feet above the highest
service connection? - ANSWER ✓ 80
9. A ? is a tank resting on the ground that is greater in height than diameter? -
ANSWER ✓ standpipe
,10.What kind of tank also known as (hydropneumatic tanks) are cylindrical and
horizontal to the ground. - ANSWER ✓ pressure tanks
11.Annual inspections on tanks must be inspected how often? - ANSWER ✓
yearly
12.Cathodic protection is an ? method for preventing corrosion of the interior of
metal tanks? - ANSWER ✓ electrochemical
13.The TCEQ requires distribution system pressure to never fall below ? psi. -
ANSWER ✓ 20
14.Under normal operating conditions, the distribution pressure must be at least
? psi. - ANSWER ✓ 35
15.Storage facilities ? demand on the water supply? - ANSWER ✓ equalize
16.Storage allows uniform pump rates, supplies water for fire fighting, and
provides time for ? - ANSWER ✓ disenfection
17.Ground storage at a surface water treatment plant is called a ? - ANSWER ✓
clear well
18.The TCEQ requires storage tanks to have covered vents, locked hatches, a
dust-proof cover, overflows with hinged flaps, and ? - ANSWER ✓ entry
ports
19.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? -
ANSWER ✓ Aeration
20.TCEQ regulation states that Shore installations , marinas, boats and houses
on the watershed must have sewage? - ANSWER ✓ disposal
21.Water aerated or chlorinated at proper pH levels oxidizes the iron and
manganese, turning them into solid? - ANSWER ✓ particles
,22.Well casing and cementing protect the well from collapse and surface ? -
ANSWER ✓ contamination
23.Sequestering does not remove iron from the water, but prevents it from
combining with oxygen and? - ANSWER ✓ reddening
24.The quantity of water a formation yields depends on the formations
thickness and? - ANSWER ✓ permeability
25.Cascade aerators, packed air-stripping towers, and air diffusers are used to
aerate? - ANSWER ✓ water
26.Aeration can be used to remove what from the water supply? - ANSWER ✓
iron and manganese
27.Hydrogen sulfide has a rotten egg odor and is oxidized by? - ANSWER ✓
super-chlorination
28.When Iron levels get this high, it can cause red stains on clothing, colored
water, or turbidity? - ANSWER ✓ 0.3 mg/L
29.Excess Manganese can cause? - ANSWER ✓ black stains
30.Another method of iron control is the use of? - ANSWER ✓ sequestering
agents
31.What is a sequestering agent? - ANSWER ✓ polyphosphates
32.Well water is sometimes? - ANSWER ✓ corrosive
33.Low ph, dissolved gases, high temperatures, and high mineral levels can
cause well water to be? - ANSWER ✓ corrosive
34.What is the process of removing calcium and magnesium by adding lime or
by exchanging ions? - ANSWER ✓ softening
35.An ion exchange replaces calcium ions with? - ANSWER ✓ sodium ions
, 36.A process available for removing arsenic, fluoride, lead, mercury, nitrate,
and silver from raw water is? - ANSWER ✓ coagulation followed by
sedimentation and filtration
37.A process that forces water through a membrane is? - ANSWER ✓ reverse
osmosis
38.In reverse osmosis a sheet of synthetic material (membrane) under pressure
prevents passage of dissolved materials and larger particles and ejects them
in a? - ANSWER ✓ waste stream
39.If a ladder is used, it must extend at least ________ feet above the edge of
the excavation and be within ________ feet laterally of anyone in the
excavation. - ANSWER ✓ 3 feet above
25 feet laterally
40.Excavation spoil must be kept at least ________ feet from the excavation. -
ANSWER ✓ 2 feet
41.Water utility employees have a right to product information under the
________. - ANSWER ✓ Texas Hazard Communication Act
42.One of the components of the Texas Hazard Communication Act is
employee access to ________. - ANSWER ✓ SDS (formerly MSDS)
43.To prevent work area accidents, workers should be trained from the Texas
Manual on Uniform Traffic Control Devices, ________, Austin. - ANSWER
✓ Texas Department of Transportation
44.A system's filtered water must be ____ Nephelometric Turbidity Units
(NTU) or less in at least _____% of the measurements taken each month,
and no sample can exceed _____ NTU. - ANSWER ✓ 0.3 NTUs
95%
1 NTU
45.For chemical analysis, surface supplies are sampled ______ a year and
groundwater is normally sampled every ______ years. - ANSWER ✓ 1 time
3 years
