ILLINOIS CLASS D WATER LICENSE
QUESTIONS AND ANSWERS
Two Towers are both 125 feet high, when full, contain 122 feet of water. Tower 1
holds 150,000 gallons. Tower 2 holds 500,000 gallons. Each has a pressure gauge
at the base. Which will register the most pressure in psi? - Answer- Both will be
equal
If the water level in tower 1 is 118 feet what will the pressure reading be at the base -
Answer- 51.1 psi
What is the definition of potable water - Answer- Water that does not contain
objectable pollution, contamination, or infective agents and is considered safe for
drinking
What is the first item used when installing a service line to a customer? - Answer-
Corporation stop
If a meter to a residence is located in the basement what should be located between
the water main and the house - Answer- curb stop
A 5/8" x 3/4" water meter serves a residence. Over a period of years the meter
__________ in recording actual water used - Answer- Decreases
To isolate part of a distribution system what type of valve is commonly used? -
Answer- Gate valve
Trihalomethanes (THMs) are caused by? - Answer- Reaction of chlorinated water
with numeric materials found in surface water sources
The longer the contact time water and chlorine residuals enjoy the ________ the
THM level will probably be - Answer- Higher
THM's should be eliminated from finished water because they cause ? - Answer-
Cancer
The maximum contaminant level for THM's is? - Answer- .080 mg/l
When collecting THM samples one sample must be taken at a site where the water
has been in the distribution system the longest time - Answer- True
An applicant for a class d test who has graduated high school but has no approved
training credits must have ____________ "hands on" experience - Answer- 6 months
What type of water main is most likely to become contaminated from gasoline
saturated soil - Answer- PVC
, What type of materials must not be used as backfill for water mains? - Answer-
Cinders
Nitrate in levels above _________ mg/L can cause "blue baby" disease - Answer- 10
A boil order must be issued if systems pressure drops below 20 psi or if
contaminated of any part of the system is suspected. Why? - Answer- It is a
regulation of the IEPA, and to protect the health of water consumers
A boil order should be issued for? - Answer- Until further notice
Upon the issuance of a boil order the IEPA regional office should be notified of the
order because ________________? - Answer- It's a state regulation
The "C" factor of a pipe is _______________? - Answer- The smoothness of the
interior of a pipe
The higher the "C" factor of a pipe the _____________ the pipe and the greater the
carrying capacity of the pipe - Answer- Smoother
A distribution system that is "looped" instead of having dead ends will help prevent -
Answer- Tastes and odors, "dirty" water, and chlorine depletion
Chlorine tablets (calcium hypochlorite) should be used for the disinfection of newly
installed water main. These tablets should be ________________ - Answer- Glued
to the top of each section
What is the definition of a water main? - Answer- Any line that passes one property
to reach another parcel of property
What is the minimum size of a water main required by the IEPA - Answer- 4 inches
in diameter
Is a construction permit from the IEPA permit section required for the installation of a
water main? - Answer- Yes
Is a construction permit from the IEPA permit section required for the installation of a
water service? - Answer- No
A three-quarter inch service line is tapped on a water main. The corporation stop
should be installed__________________ - Answer- At an angle between the top and
side of the main
A 6 inch PVC Watermain is installed what should be installed at the end of the main -
Answer- Concrete thrusting block
Cathodic protection in a storage tank is? - Answer- A small electric current used to
prevent rust, corrosion, and pitting of metal surfaces
QUESTIONS AND ANSWERS
Two Towers are both 125 feet high, when full, contain 122 feet of water. Tower 1
holds 150,000 gallons. Tower 2 holds 500,000 gallons. Each has a pressure gauge
at the base. Which will register the most pressure in psi? - Answer- Both will be
equal
If the water level in tower 1 is 118 feet what will the pressure reading be at the base -
Answer- 51.1 psi
What is the definition of potable water - Answer- Water that does not contain
objectable pollution, contamination, or infective agents and is considered safe for
drinking
What is the first item used when installing a service line to a customer? - Answer-
Corporation stop
If a meter to a residence is located in the basement what should be located between
the water main and the house - Answer- curb stop
A 5/8" x 3/4" water meter serves a residence. Over a period of years the meter
__________ in recording actual water used - Answer- Decreases
To isolate part of a distribution system what type of valve is commonly used? -
Answer- Gate valve
Trihalomethanes (THMs) are caused by? - Answer- Reaction of chlorinated water
with numeric materials found in surface water sources
The longer the contact time water and chlorine residuals enjoy the ________ the
THM level will probably be - Answer- Higher
THM's should be eliminated from finished water because they cause ? - Answer-
Cancer
The maximum contaminant level for THM's is? - Answer- .080 mg/l
When collecting THM samples one sample must be taken at a site where the water
has been in the distribution system the longest time - Answer- True
An applicant for a class d test who has graduated high school but has no approved
training credits must have ____________ "hands on" experience - Answer- 6 months
What type of water main is most likely to become contaminated from gasoline
saturated soil - Answer- PVC
, What type of materials must not be used as backfill for water mains? - Answer-
Cinders
Nitrate in levels above _________ mg/L can cause "blue baby" disease - Answer- 10
A boil order must be issued if systems pressure drops below 20 psi or if
contaminated of any part of the system is suspected. Why? - Answer- It is a
regulation of the IEPA, and to protect the health of water consumers
A boil order should be issued for? - Answer- Until further notice
Upon the issuance of a boil order the IEPA regional office should be notified of the
order because ________________? - Answer- It's a state regulation
The "C" factor of a pipe is _______________? - Answer- The smoothness of the
interior of a pipe
The higher the "C" factor of a pipe the _____________ the pipe and the greater the
carrying capacity of the pipe - Answer- Smoother
A distribution system that is "looped" instead of having dead ends will help prevent -
Answer- Tastes and odors, "dirty" water, and chlorine depletion
Chlorine tablets (calcium hypochlorite) should be used for the disinfection of newly
installed water main. These tablets should be ________________ - Answer- Glued
to the top of each section
What is the definition of a water main? - Answer- Any line that passes one property
to reach another parcel of property
What is the minimum size of a water main required by the IEPA - Answer- 4 inches
in diameter
Is a construction permit from the IEPA permit section required for the installation of a
water main? - Answer- Yes
Is a construction permit from the IEPA permit section required for the installation of a
water service? - Answer- No
A three-quarter inch service line is tapped on a water main. The corporation stop
should be installed__________________ - Answer- At an angle between the top and
side of the main
A 6 inch PVC Watermain is installed what should be installed at the end of the main -
Answer- Concrete thrusting block
Cathodic protection in a storage tank is? - Answer- A small electric current used to
prevent rust, corrosion, and pitting of metal surfaces
