divided modules, ACTUAL EXAM 2024-2025
WITH DETAILED QUESTIONS AND CORRECT
ANSWERS
A common chemical used in the disenfection of a small water supply is-
- Correct Answer- Calcium Hypochlorite
A physical connection between a potable water supply and a house well would be-
- Correct Answer- A Cross Connection
The amount of Chlorine in mg/L that is used by reacting with iron, organics, or
bacteria is called? - Correct Answer- Demand
All of the following are Physical characteristics of Chlorine gas-
- Correct Answer-
Greenish Yellow color
Heavier than air
Pungent, Penetrating odor
Corrosive
Which of the following would be considered a part of a hypo-chlorinator system?
- Correct Answer- Solution feed pump
According to state requirements, all public water supply wells should be provided
with a raised concrete sealing block, screened vents and-
- Correct Answer- Flow measuring device
,The drawdown of a water well is determined by-
- Correct Answer- The difference in static and pumping levels
The pH of water indicates-
- Correct Answer- If it is more acidic or base
The pH of water is expressed by a scale of numbers ranging from-
- Correct Answer- 0-14
Water that is considered neutral is expressed on the pH scale at-
- Correct Answer- 7.0
Which of the following is a required step in collecting a routine distribution sample
for bacteriological testing?
- Correct Answer- Use of an approved, sterile container
Sand filtration will remove which of the following from surface water?
- Correct Answer- Turbidity
Activated Carbon is used in a Surface Water Plant primarily for?
- Correct Answer- Taste and Odor control
Which of the following chemical(s) are commonly used as coagulants in surface
water treatment?
- Correct Answer- Alum and Ferric Chloride
,Ground storage tanks are required to be provided with which of the following?
- Correct Answer-
Screened Vents
An approved locking roof hatch
An overflow pipe with hinged flap device
Annual inspection and maintenance as needed
An elevated storage tank should be protected against corrosion by-
- Correct Answer-
Painting
Cathodic protection
Water stabilization
A public water supply system should maintain residual pressure of 20 psi and a
minimum normal operating pressure of-
- Correct Answer- 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 detention time.
- Correct Answer- 50 mg/L
Water bearing formations beneath the earth's surface that are used as a source of
water for public water supplies are-
- Correct Answer- Aquifers
, The purpose of an air line on a well is-
- Correct Answer- Determine water levels in the well
The mesh size is an important feature of a well screen because property sized
openings should-
- Correct Answer- Reduce the amount of sand pumped
When treating surface water, the process of coagulation will be most affected by
the- - Correct Answer- pH, alkalinity, temperature, and chemical dosage
A rapid sand filter should be backwashed when- - Correct Answer- When the loss
of head gauge indicated between 6 and 10 ft.
Which of the following is an acceptable disinfection residual at the far reaches of
the distribution system- - Correct Answer- 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
One gallon of water weighs- - Correct Answer- 8.34 lbs
One foot of water inside a storage vessel will raise a pressure gauge at the bottom
of the vessel by- - Correct Answer- .433 lbs
A raw water intake structure may not be constructed within _____ feet of a boat
ramp, dock, or marina - Correct Answer- 1000 ft