Page | 1
COMMERCIAL CONTRACTOR EXAM
QUESTIONS WITH DETAILED VERIFIED
ANSWERS
The ____________________ will focus on larger commercial or
industrial installations that may require additional features such as
pretreatment of high strength effluent, dosing devices, or components
such as tanks which have to be built or fabricated at the construction
site. Ans: Commercial Contractors Certification
Some commercial installations may be able to use pre-cast tanks made of
____________________ or such other materials. Ans: concrete, plastic,
fiberglass
The treatment capacity for all septic tanks shall be sized for the
__________ of the facility being served. Ans: daily (24 hours) peak flow
volume
Septic tanks may be trained together, however, the volume of the first
compartment of the first treatment tank shall be at least _________ the
volume of the total 24-hour flow. Ans: two-thirds
The minimum tank size shall be ________ gallons. Ans: 1000
In facilities where garbage grinders are used, total tank capacity shall be
increased by _________. Ans: 50%
All tanks shall be equipped with ______ inch PVC, ASTM 3034 rated or
equivalent teens at the inlet and outlet ends of the tank. Ans: 4
Tees shall be extend so they extend into the liquid a minimum of ______
and a maximum of _____ of the liquid depth of the tank. Ans: 25%;
50%
__________ shall be equipped with an effluent filter designed to handle
both the daily flow volume and wastewater characteristics. Ans: Outlet
tees
, Page | 2
All tanks whether pre-made or constructed on site shall be constructed so
the length is at least ______ times the width and shall have ______
compartments. Ans: 1 1/5; 2
Tank compartments partitions will be located at a point not less than
______ or more than ______ the length of the tank from the inlet end.
Ans: two-thirds; three-fourths
_____________ will be constructed so a pass-through hole or slot equal
to or greater than the diameter of the inlet pipe is positioned below the
liquid surface a minimum of 25% to a maximum of 50% of the total
liquid depth. Ans: Compartment partitions
The ___________________ of poured-in-place septic tanks must be
reinforced. Ans: walls and bottom
Reinforcing can be accomplished by using either a minimum
____________ No. 10 gage welded steel reinforcing wire or fibrous
reinforcing material conforming to ASTM specifications for such materials.
Ans: 6x6
________________ must be reinforced using 3/8 inch steel reinforcing
rods (rebar) which shall be spaced 12" on center each way extending a
minimum of 2.5" and a maximum of 3" from the outside of the tank lid.
Ans: Tank lids
In general, the __________ must be able to withstand a uniform live
load of 150 pounds per square foot in addition to all loads to which an
underground tank is normally subjected. Ans: tank
Additional reinforcement shall be required when the loads on a
_________________ are exceeded by subjecting it to vehicular traffic or
when the top of the tank is placed deeper than 3 feet below the finished
grade. Ans: concrete tank
____________________________ of poured in place septic systems
shall have a minimum thickness of 4 inches. Ans: Walls, bottoms, and
lids
Tank lids shall be constructed in ____________ pieces. Ans: one or two
COMMERCIAL CONTRACTOR EXAM
QUESTIONS WITH DETAILED VERIFIED
ANSWERS
The ____________________ will focus on larger commercial or
industrial installations that may require additional features such as
pretreatment of high strength effluent, dosing devices, or components
such as tanks which have to be built or fabricated at the construction
site. Ans: Commercial Contractors Certification
Some commercial installations may be able to use pre-cast tanks made of
____________________ or such other materials. Ans: concrete, plastic,
fiberglass
The treatment capacity for all septic tanks shall be sized for the
__________ of the facility being served. Ans: daily (24 hours) peak flow
volume
Septic tanks may be trained together, however, the volume of the first
compartment of the first treatment tank shall be at least _________ the
volume of the total 24-hour flow. Ans: two-thirds
The minimum tank size shall be ________ gallons. Ans: 1000
In facilities where garbage grinders are used, total tank capacity shall be
increased by _________. Ans: 50%
All tanks shall be equipped with ______ inch PVC, ASTM 3034 rated or
equivalent teens at the inlet and outlet ends of the tank. Ans: 4
Tees shall be extend so they extend into the liquid a minimum of ______
and a maximum of _____ of the liquid depth of the tank. Ans: 25%;
50%
__________ shall be equipped with an effluent filter designed to handle
both the daily flow volume and wastewater characteristics. Ans: Outlet
tees
, Page | 2
All tanks whether pre-made or constructed on site shall be constructed so
the length is at least ______ times the width and shall have ______
compartments. Ans: 1 1/5; 2
Tank compartments partitions will be located at a point not less than
______ or more than ______ the length of the tank from the inlet end.
Ans: two-thirds; three-fourths
_____________ will be constructed so a pass-through hole or slot equal
to or greater than the diameter of the inlet pipe is positioned below the
liquid surface a minimum of 25% to a maximum of 50% of the total
liquid depth. Ans: Compartment partitions
The ___________________ of poured-in-place septic tanks must be
reinforced. Ans: walls and bottom
Reinforcing can be accomplished by using either a minimum
____________ No. 10 gage welded steel reinforcing wire or fibrous
reinforcing material conforming to ASTM specifications for such materials.
Ans: 6x6
________________ must be reinforced using 3/8 inch steel reinforcing
rods (rebar) which shall be spaced 12" on center each way extending a
minimum of 2.5" and a maximum of 3" from the outside of the tank lid.
Ans: Tank lids
In general, the __________ must be able to withstand a uniform live
load of 150 pounds per square foot in addition to all loads to which an
underground tank is normally subjected. Ans: tank
Additional reinforcement shall be required when the loads on a
_________________ are exceeded by subjecting it to vehicular traffic or
when the top of the tank is placed deeper than 3 feet below the finished
grade. Ans: concrete tank
____________________________ of poured in place septic systems
shall have a minimum thickness of 4 inches. Ans: Walls, bottoms, and
lids
Tank lids shall be constructed in ____________ pieces. Ans: one or two
