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CNMI Underground Utility Installer Certification Exam
Practice Questions And Correct Answers||Verified
Exam!!|| (Verified Answers) Plus Rationales 2026/2027
Q&A | Instant Download Pdf
In soils that are approved by percolation tests or evaluated
to have absorption rates higher than 60 MPI LDGP
systems require?
a) installation in a 24 inch trench with gravel back fill
leveled to the top of the LDGP
b) installation in a 24 inch trench with a quality top soil
backfill
c) installation in an 18 inch trench with gravel backfill to
the top of the LDGP
d) installation in a 24 inch trench with gravel backfill to 2
inches above LDGP - Answer-a) installation in a 24 inch
trench with gravel back fill leveled to the top of the LDGP
The maximum trench width allowed for a 24 inch wide
chamber product is
a) 24 inches
b) 30 inches
c) 34 inches
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d) 36 inches - Answer-b) 30 inches
What is the proper volume of a dosing (pump) chamber?
a) same as the septic tank
b) 1000 gallons
c) two times the daily waste water flow
d) 900 gallons - Answer-c) two times the daily waste water
flow
When installing conventional and conventional substitute
systems
a) disposal field trenches shall follow the contour of the
ground surface
b) a minimum of 6 ft of undisturbed earth shall be required
between trenches
c) trenches shall not be excavated when the soil is wet
enough to smear or compact
d) all of the above - Answer-d) all the above
An installer may call for a final inspection on a system that
utilizes a pumped dosing system after?
a) the field lines have been installed
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b) the septic tank, pump tank, and field lines have been
installed and the electrical inspector has inspected and
approved the electrical component of the system
c) the house is built and electricity is turned on - Answer-b)
the septic tank, pump tank, and field lines have been
installed and the electrical inspector has inspected and
approved the electrical components of the system
The maximum amount of falll allowed in the bottom of a
conventional dispossal trench is
a) 2 inches
b) 4 inches
c) 6 inches - Answer-b) 4 inches
WHen installing an SSD system where a basement cut in
involved, what is the mimum distance the septic/dosing
tank and absorption field can be installed from the
basement cut?
a) 15 ft for the tanks and 15 ft for the absorption field
b) 10 ft for the tanks and 25 ft for the aborption field
c) 15 ft for the tanks and 25 ft for the absorption field
CNMI Underground Utility Installer Certification Exam
Practice Questions And Correct Answers||Verified
Exam!!|| (Verified Answers) Plus Rationales 2026/2027
Q&A | Instant Download Pdf
In soils that are approved by percolation tests or evaluated
to have absorption rates higher than 60 MPI LDGP
systems require?
a) installation in a 24 inch trench with gravel back fill
leveled to the top of the LDGP
b) installation in a 24 inch trench with a quality top soil
backfill
c) installation in an 18 inch trench with gravel backfill to
the top of the LDGP
d) installation in a 24 inch trench with gravel backfill to 2
inches above LDGP - Answer-a) installation in a 24 inch
trench with gravel back fill leveled to the top of the LDGP
The maximum trench width allowed for a 24 inch wide
chamber product is
a) 24 inches
b) 30 inches
c) 34 inches
,2|Page
d) 36 inches - Answer-b) 30 inches
What is the proper volume of a dosing (pump) chamber?
a) same as the septic tank
b) 1000 gallons
c) two times the daily waste water flow
d) 900 gallons - Answer-c) two times the daily waste water
flow
When installing conventional and conventional substitute
systems
a) disposal field trenches shall follow the contour of the
ground surface
b) a minimum of 6 ft of undisturbed earth shall be required
between trenches
c) trenches shall not be excavated when the soil is wet
enough to smear or compact
d) all of the above - Answer-d) all the above
An installer may call for a final inspection on a system that
utilizes a pumped dosing system after?
a) the field lines have been installed
, 3|Page
b) the septic tank, pump tank, and field lines have been
installed and the electrical inspector has inspected and
approved the electrical component of the system
c) the house is built and electricity is turned on - Answer-b)
the septic tank, pump tank, and field lines have been
installed and the electrical inspector has inspected and
approved the electrical components of the system
The maximum amount of falll allowed in the bottom of a
conventional dispossal trench is
a) 2 inches
b) 4 inches
c) 6 inches - Answer-b) 4 inches
WHen installing an SSD system where a basement cut in
involved, what is the mimum distance the septic/dosing
tank and absorption field can be installed from the
basement cut?
a) 15 ft for the tanks and 15 ft for the absorption field
b) 10 ft for the tanks and 25 ft for the aborption field
c) 15 ft for the tanks and 25 ft for the absorption field
