Class "C" Water Exam (Answered)
2025/2026. 100% Verified.
Calcium Hypochlorite
A common chemical used in the disenfection of a small water supply is-
A Cross Connection
A physical connection between a potable water supply and a house well would be-
Demand
The amount of Chlorine in mg/L that is used by reacting with iron, organics, or bacteria is called?
Greenish Yellow color
Heavier than air
Pungent, Penetrating odor
Corrosive
All of the following are Physical characteristics of Chlorine gas-
Solution feed pump
Which of the following would be considered a part of a hypo-chlorinator system?
Flow measuring device
According to state requirements, all public water supply wells should be provided with a raised
concrete sealing block, screened vents and-
The difference in static and pumping levels
The drawdown of a water well is determined by-
If it is more acidic or base
The pH of water indicates-
0-14
The pH of water is expressed by a scale of numbers ranging from-
7.0
Water that is considered neutral is expressed on the pH scale at-
Use of an approved, sterile container
Which of the following is a required step in collecting a routine distribution sample for
bacteriological testing?
Turbidity
Sand filtration will remove which of the following from surface water?
, Taste and Odor control
Activated Carbon is used in a Surface Water Plant primarily for?
Alum and Ferric Chloride
Which of the following chemical(s) are commonly used as coagulants in surface water treatment?
Screened Vents
An approved locking roof hatch
An overflow pipe with hinged flap device
Annual inspection and maintenance as needed
Ground storage tanks are required to be provided with which of the following?
Painting
Cathodic protection
Water stabilization
An elevated storage tank should be protected against corrosion by-
35 psi
A public water supply system should maintain residual pressure of 20 psi and a minimum normal
operating pressure of-
50 mg/L
Before a new or repaired water line is placed into service, it must be properly disinfected by
providing a chlorine dosage of _____ and proper detention time.
Aquifers
Water bearing formations beneath the earth's surface that are used as a source of water for public
water supplies are-
Determine water levels in the well
The purpose of an air line on a well is-
Reduce the amount of sand pumped
The mesh size is an important feature of a well screen because property sized openings should-
pH, alkalinity, temperature, and chemical dosage
When treating surface water, the process of coagulation will be most affected by the-
When the loss of head gauge indicated between 6 and 10 ft.
A rapid sand filter should be backwashed when-
0.2 mg/L free chlorine residual
0.5 mg/L chloramine residual for a surface water supply
0.8 mg/L chloramine residual when using chloramine treatment
0.5 mg/L free chlorine residual for a groundwater supply
2025/2026. 100% Verified.
Calcium Hypochlorite
A common chemical used in the disenfection of a small water supply is-
A Cross Connection
A physical connection between a potable water supply and a house well would be-
Demand
The amount of Chlorine in mg/L that is used by reacting with iron, organics, or bacteria is called?
Greenish Yellow color
Heavier than air
Pungent, Penetrating odor
Corrosive
All of the following are Physical characteristics of Chlorine gas-
Solution feed pump
Which of the following would be considered a part of a hypo-chlorinator system?
Flow measuring device
According to state requirements, all public water supply wells should be provided with a raised
concrete sealing block, screened vents and-
The difference in static and pumping levels
The drawdown of a water well is determined by-
If it is more acidic or base
The pH of water indicates-
0-14
The pH of water is expressed by a scale of numbers ranging from-
7.0
Water that is considered neutral is expressed on the pH scale at-
Use of an approved, sterile container
Which of the following is a required step in collecting a routine distribution sample for
bacteriological testing?
Turbidity
Sand filtration will remove which of the following from surface water?
, Taste and Odor control
Activated Carbon is used in a Surface Water Plant primarily for?
Alum and Ferric Chloride
Which of the following chemical(s) are commonly used as coagulants in surface water treatment?
Screened Vents
An approved locking roof hatch
An overflow pipe with hinged flap device
Annual inspection and maintenance as needed
Ground storage tanks are required to be provided with which of the following?
Painting
Cathodic protection
Water stabilization
An elevated storage tank should be protected against corrosion by-
35 psi
A public water supply system should maintain residual pressure of 20 psi and a minimum normal
operating pressure of-
50 mg/L
Before a new or repaired water line is placed into service, it must be properly disinfected by
providing a chlorine dosage of _____ and proper detention time.
Aquifers
Water bearing formations beneath the earth's surface that are used as a source of water for public
water supplies are-
Determine water levels in the well
The purpose of an air line on a well is-
Reduce the amount of sand pumped
The mesh size is an important feature of a well screen because property sized openings should-
pH, alkalinity, temperature, and chemical dosage
When treating surface water, the process of coagulation will be most affected by the-
When the loss of head gauge indicated between 6 and 10 ft.
A rapid sand filter should be backwashed when-
0.2 mg/L free chlorine residual
0.5 mg/L chloramine residual for a surface water supply
0.8 mg/L chloramine residual when using chloramine treatment
0.5 mg/L free chlorine residual for a groundwater supply
