TCEQ class c water license exam Ques ons and answers
NEWEST RATED A+ 2025/2026 100% VERIFIED CORRECT
State Agency responsince for enforcing the safe drinking water act in Texas
Texas Commission on environmental Quality
What minerals can cause water hardness
Calcium and magnesium
A public water system must at all mes provide
Adequate quan ty of water, pressure, and disinfec on
A source groundwater would be
aquifer
Fecal coliform organisms some mes found in water supplies are an indica on that
Water supply is contaminated, harmful bacteria may be present, possible pathogenic organisms
in the water, water is unsuitable for drinking
A disease that may be spread by inadequately disinfected water
Dysentery
A common chemical used in disinfec on of small water supply is
Calcium hypochlorite
A physical connec on between a potable water supply and house well would be
A cross connec on
The amount of chlorine in mg/L that is used up by reac ng with iron organics of bacteria is
called
Demand
Which of the following is a physical characteris c of chlorine gas
Greenish-Yellow Color, heavier than air, pungent penetra ng odor, corrosive
Which of the following would be considered a part of a hypo-chlorinator system
Solu on feed pump
,According to state requirements, all public water Supply wells should be provided with a raised
concrete sealing block, screened vents, and-
A flow measuring device
AD
Drawdown of a water well is determined by
Difference in sta c and pumping levels
pH of water indicates
If it's acidic or basic
The pH of water is expressed on a pH scale of
0-14
Water that is considered neutral is expressed on the pH scale at
7.0
Which of the following is a required Step in collec ng a rou ne distribu on sample for
bacteriological tes ng?
Use of an approved, sterile sample container
Sand filtra on will remove which of the following from surface water
Turbidity
Ac vated carbon is used in a surface water plant primarily for
Taste and odor control
Which or the following chemicals are commonly used as coagulants in surface water treatment
Alum and ferric chloride
Ground storage tanks are required to provided with which of the following
Screened vents, an approved locking roof hatch, an overflow pipe with hinged flap device,
annual inspec on and maintenance as needed
An elevated storage tank should be protected against corrosion by
Pain ng, cathodic protec on, water stabiliza on, and only using galvanized and lead based
primed components
, AD
A public water supply system should maintain residual pressure of 20 psi and a minimum of
normal opera ng pressure of
35 psi
Before a new or repaired water line is placed into service, it must be properly disinfected by
providing a chlorine dosage of _________ and proper deten on me
50 mg/L
Water bearing forma ons beneath the earths surface that are used as a source of water for
public water supplies are
Aquifers
The purpose of an air line on a well is
Determine Water leves in the well
The mesh size is an important feature of a well screen because properly sized openings should
Reduce the amount of Sand pumped
When trea ng surface Water, the process of coagularon will be most affected by the
pH, alkalinity, temperature, and chemical Dosage
A rapid sand filter should be backwashed When
The loss of head gauge indicated between 6 and 10 feet
Which of the following is an acceptable disinfec on residual at the far reaches of the
distribu on System
0.2 mg/L free chlorine residual, 0.8 mg/L chloramine residual when using chloramine treatment,
0.5 mg/L chloramine for surface water supply, 0.5 mg/L free chlorine residual for ground water
Supply
What is the approximate total volume of a circular tank in gallons, if it is 30 feet in diameter, and
15 feet deep
79,300 gallons
You are using a chlorinator to provine a dosage of 4.0 mg/L. If the daily Water usage is 750,000
gallons, the gas chlorinator feed rate should be set at ____________ pounds per day.
NEWEST RATED A+ 2025/2026 100% VERIFIED CORRECT
State Agency responsince for enforcing the safe drinking water act in Texas
Texas Commission on environmental Quality
What minerals can cause water hardness
Calcium and magnesium
A public water system must at all mes provide
Adequate quan ty of water, pressure, and disinfec on
A source groundwater would be
aquifer
Fecal coliform organisms some mes found in water supplies are an indica on that
Water supply is contaminated, harmful bacteria may be present, possible pathogenic organisms
in the water, water is unsuitable for drinking
A disease that may be spread by inadequately disinfected water
Dysentery
A common chemical used in disinfec on of small water supply is
Calcium hypochlorite
A physical connec on between a potable water supply and house well would be
A cross connec on
The amount of chlorine in mg/L that is used up by reac ng with iron organics of bacteria is
called
Demand
Which of the following is a physical characteris c of chlorine gas
Greenish-Yellow Color, heavier than air, pungent penetra ng odor, corrosive
Which of the following would be considered a part of a hypo-chlorinator system
Solu on feed pump
,According to state requirements, all public water Supply wells should be provided with a raised
concrete sealing block, screened vents, and-
A flow measuring device
AD
Drawdown of a water well is determined by
Difference in sta c and pumping levels
pH of water indicates
If it's acidic or basic
The pH of water is expressed on a pH scale of
0-14
Water that is considered neutral is expressed on the pH scale at
7.0
Which of the following is a required Step in collec ng a rou ne distribu on sample for
bacteriological tes ng?
Use of an approved, sterile sample container
Sand filtra on will remove which of the following from surface water
Turbidity
Ac vated carbon is used in a surface water plant primarily for
Taste and odor control
Which or the following chemicals are commonly used as coagulants in surface water treatment
Alum and ferric chloride
Ground storage tanks are required to provided with which of the following
Screened vents, an approved locking roof hatch, an overflow pipe with hinged flap device,
annual inspec on and maintenance as needed
An elevated storage tank should be protected against corrosion by
Pain ng, cathodic protec on, water stabiliza on, and only using galvanized and lead based
primed components
, AD
A public water supply system should maintain residual pressure of 20 psi and a minimum of
normal opera ng pressure of
35 psi
Before a new or repaired water line is placed into service, it must be properly disinfected by
providing a chlorine dosage of _________ and proper deten on me
50 mg/L
Water bearing forma ons beneath the earths surface that are used as a source of water for
public water supplies are
Aquifers
The purpose of an air line on a well is
Determine Water leves in the well
The mesh size is an important feature of a well screen because properly sized openings should
Reduce the amount of Sand pumped
When trea ng surface Water, the process of coagularon will be most affected by the
pH, alkalinity, temperature, and chemical Dosage
A rapid sand filter should be backwashed When
The loss of head gauge indicated between 6 and 10 feet
Which of the following is an acceptable disinfec on residual at the far reaches of the
distribu on System
0.2 mg/L free chlorine residual, 0.8 mg/L chloramine residual when using chloramine treatment,
0.5 mg/L chloramine for surface water supply, 0.5 mg/L free chlorine residual for ground water
Supply
What is the approximate total volume of a circular tank in gallons, if it is 30 feet in diameter, and
15 feet deep
79,300 gallons
You are using a chlorinator to provine a dosage of 4.0 mg/L. If the daily Water usage is 750,000
gallons, the gas chlorinator feed rate should be set at ____________ pounds per day.
