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COMMERCIAL SEPTIC SYSTEM INSTALLER
EXAM 2026 ALL QUESTIONS AND CORRECT
DETAILED ANSWERS ALREADY A GRADED
WITH EXPERT FEEDBACK |NEW AND REVISED
How can a Septic tank be reinforced? - ANSWER- 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? - ANSWER- 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. - ANSWER-
150
True or False: Walls, bottoms, and lids of poured-in-place septic tanks
should have a minimum thickness of four inches (4"). - ANSWER- True
Tank lids shall be constructed in ______________________ pieces and
shall have securable, removable access openings located so that the inlet
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and outlet tees can be ________________________________. -
ANSWER- one or two,
Readily accessed.
Access opening shall have a minimum of _________________ and
maximum of ___________________ free space. - ANSWER-
Minimum: 15"
Maximum: 24"
Tanks with more than 12 inches of cover must extend access openings to
within ______ inches of the ground surface. - ANSWER- 12
All tanks shall be equipped with ________________________________
rated or equivalent tees at the inlet and outlet ends of the tank. -
ANSWER- Four inch (4") PVC, ASTM 3034
Tees shall be constructed so they extend into the liquid a minimum of
____________________ and a maximum of __________________ of
the liquid depth of the tank. - ANSWER- Min: 25%
Max: 50%
The invert of the outlet tee shall be located _______________ inches
below the invert of the inlet tee. - ANSWER- two inches
__________________ tees shall be equipped with an approved effluent
filter. - ANSWER- Outlet
COMMERCIAL SEPTIC SYSTEM INSTALLER
EXAM 2026 ALL QUESTIONS AND CORRECT
DETAILED ANSWERS ALREADY A GRADED
WITH EXPERT FEEDBACK |NEW AND REVISED
How can a Septic tank be reinforced? - ANSWER- 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? - ANSWER- 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. - ANSWER-
150
True or False: Walls, bottoms, and lids of poured-in-place septic tanks
should have a minimum thickness of four inches (4"). - ANSWER- True
Tank lids shall be constructed in ______________________ pieces and
shall have securable, removable access openings located so that the inlet
, 2|Page
and outlet tees can be ________________________________. -
ANSWER- one or two,
Readily accessed.
Access opening shall have a minimum of _________________ and
maximum of ___________________ free space. - ANSWER-
Minimum: 15"
Maximum: 24"
Tanks with more than 12 inches of cover must extend access openings to
within ______ inches of the ground surface. - ANSWER- 12
All tanks shall be equipped with ________________________________
rated or equivalent tees at the inlet and outlet ends of the tank. -
ANSWER- Four inch (4") PVC, ASTM 3034
Tees shall be constructed so they extend into the liquid a minimum of
____________________ and a maximum of __________________ of
the liquid depth of the tank. - ANSWER- Min: 25%
Max: 50%
The invert of the outlet tee shall be located _______________ inches
below the invert of the inlet tee. - ANSWER- two inches
__________________ tees shall be equipped with an approved effluent
filter. - ANSWER- Outlet
