Commercial Septic System Installer Exam
questions with verified answers
All tanks must have: Ans✔✔✔-2 compartments
All tanks whether pre-manufactured or constructed on site shall be constructed
so that the length is ___________ compared to the width. Ans✔✔✔-at least one
and one- half (1 1/2) times... "to the width."
Septic Tanks may be made of: Ans✔✔✔-Concrete, Plastic, fiberglass, or other
materials as approved by the department.
Tank compartment partitions will be located: Ans✔✔✔-Not less than two-thirds
or more than three-fourths the Length of the tank from the Inlet end.
Compartment partitions will be constructed so a pass-thru hole or slot equal to or
greater than the diameter of the inlet pipe is positioned below the liquid surface
with a _____________________________. Ans✔✔✔-Minimum 25% to a
maximum of 50% of the total liquid depth.
Total liquid depth for larger poured-in-place tanks shall have a maximum of
______________inches Ans✔✔✔-66 inches
True or False: Walls and bottom of poured-in-place septic tanks must be
reinforced. Ans✔✔✔-True
, How can a Septic tank be reinforced? Ans✔✔✔-six inch by 6 inch (6"x6") No.10
gage welded steel reinforcing wire OR fibrous reinforcing material conforming to
ASTM specifications for such materials.
How must Tank Lids be Reinforced? Ans✔✔✔-using three-eights steel reinforcing
rods (rebar) which shall be spaced twelve inches (12") on center each way
extending a minimum of two and one half (2 1/2") inches and a maximum of
three (3") from the outside edge of the tank lid.
In general, the tank must be able to withstand a uniform live load of
______________________ pounds per square foot in addition to all loads to
which an underground tank is normally subjected. Ans✔✔✔-150
True or False: Walls, bottoms, and lids of poured-in-place septic tanks should have
a minimum thickness of four inches (4"). Ans✔✔✔-True
Tank lids shall be constructed in ______________________ pieces and shall have
securable, removable access openings located so that the inlet and outlet tees
can be ________________________________. Ans✔✔✔-one or two,
readily accessed.
Access opening shall have a minimum of _________________ and maximum of
___________________ free space. Ans✔✔✔-Minimum: 15"
Maximum: 24"
Tanks with more than 12 inches of cover must extend access openings to within
______ inches of the ground surface. Ans✔✔✔-12
questions with verified answers
All tanks must have: Ans✔✔✔-2 compartments
All tanks whether pre-manufactured or constructed on site shall be constructed
so that the length is ___________ compared to the width. Ans✔✔✔-at least one
and one- half (1 1/2) times... "to the width."
Septic Tanks may be made of: Ans✔✔✔-Concrete, Plastic, fiberglass, or other
materials as approved by the department.
Tank compartment partitions will be located: Ans✔✔✔-Not less than two-thirds
or more than three-fourths the Length of the tank from the Inlet end.
Compartment partitions will be constructed so a pass-thru hole or slot equal to or
greater than the diameter of the inlet pipe is positioned below the liquid surface
with a _____________________________. Ans✔✔✔-Minimum 25% to a
maximum of 50% of the total liquid depth.
Total liquid depth for larger poured-in-place tanks shall have a maximum of
______________inches Ans✔✔✔-66 inches
True or False: Walls and bottom of poured-in-place septic tanks must be
reinforced. Ans✔✔✔-True
, How can a Septic tank be reinforced? Ans✔✔✔-six inch by 6 inch (6"x6") No.10
gage welded steel reinforcing wire OR fibrous reinforcing material conforming to
ASTM specifications for such materials.
How must Tank Lids be Reinforced? Ans✔✔✔-using three-eights steel reinforcing
rods (rebar) which shall be spaced twelve inches (12") on center each way
extending a minimum of two and one half (2 1/2") inches and a maximum of
three (3") from the outside edge of the tank lid.
In general, the tank must be able to withstand a uniform live load of
______________________ pounds per square foot in addition to all loads to
which an underground tank is normally subjected. Ans✔✔✔-150
True or False: Walls, bottoms, and lids of poured-in-place septic tanks should have
a minimum thickness of four inches (4"). Ans✔✔✔-True
Tank lids shall be constructed in ______________________ pieces and shall have
securable, removable access openings located so that the inlet and outlet tees
can be ________________________________. Ans✔✔✔-one or two,
readily accessed.
Access opening shall have a minimum of _________________ and maximum of
___________________ free space. Ans✔✔✔-Minimum: 15"
Maximum: 24"
Tanks with more than 12 inches of cover must extend access openings to within
______ inches of the ground surface. Ans✔✔✔-12
