Minnesota Subsurface Sewage
Treatment System Inspector Exam
Practice Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. What is the primary purpose of a Subsurface Sewage Treatment
System (SSTS) inspection?
A. To determine property tax value
B. To verify that the system protects public health and the environment
C. To increase wastewater flow capacity
D. To replace all septic systems annually
Answer: B. To verify that the system protects public health and the
environment
The purpose of an SSTS inspection is to evaluate whether the system
functions properly and prevents sewage from contaminating groundwater,
surface water, and surrounding areas.
, 2. Which Minnesota agency oversees statewide SSTS regulations?
A. Minnesota Department of Transportation
B. Minnesota Department of Natural Resources
C. Minnesota Pollution Control Agency
D. Minnesota Department of Agriculture
Answer: C. Minnesota Pollution Control Agency
The Minnesota Pollution Control Agency establishes statewide SSTS rules
and standards that local authorities use for regulation and enforcement.
3. A compliant septic system must primarily prevent:
A. Soil erosion only
B. Sewage discharge and public exposure risks
C. Rainwater collection
D. Building foundation movement
Answer: B. Sewage discharge and public exposure risks
A properly functioning SSTS treats wastewater and prevents untreated
sewage from reaching people, groundwater, or surface waters.
4. During an inspection, the first step should usually be:
A. Pumping the tank immediately
B. Reviewing available records and system information
,C. Removing the drainfield soil
D. Replacing the distribution box
Answer: B. Reviewing available records and system information
Inspectors begin by gathering information such as permits, previous
inspections, and system design details before field evaluation.
5. The septic tank’s main function is to:
A. Completely disinfect wastewater
B. Separate solids and allow primary treatment
C. Pump wastewater directly into soil
D. Increase groundwater levels
Answer: B. Separate solids and allow primary treatment
The septic tank allows solids to settle, scum to float, and partially treated
effluent to move to the next treatment stage.
6. Which condition indicates a potential SSTS failure?
A. Properly functioning absorption area
B. Sewage surfacing on the ground
C. Regular maintenance pumping
D. Proper tank access covers
Answer: B. Sewage surfacing on the ground
, Sewage surfacing indicates inadequate treatment or hydraulic failure and
creates a direct public health concern.
7. The drainfield treats wastewater mainly through:
A. Chemical additives
B. Soil filtration and biological activity
C. Chlorination only
D. Mechanical screening
Answer: B. Soil filtration and biological activity
The soil beneath the drainfield provides treatment by filtering particles and
supporting microorganisms that break down contaminants.
8. A septic tank inspection should include checking:
A. Tank integrity and liquid levels
B. Roof structure
C. Electrical wiring only
D. Interior plumbing fixtures only
Answer: A. Tank integrity and liquid levels
Inspectors evaluate the tank for leaks, damage, proper liquid levels, and
evidence of hydraulic problems.
9. What is the purpose of septic tank baffles?
Treatment System Inspector Exam
Practice Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. What is the primary purpose of a Subsurface Sewage Treatment
System (SSTS) inspection?
A. To determine property tax value
B. To verify that the system protects public health and the environment
C. To increase wastewater flow capacity
D. To replace all septic systems annually
Answer: B. To verify that the system protects public health and the
environment
The purpose of an SSTS inspection is to evaluate whether the system
functions properly and prevents sewage from contaminating groundwater,
surface water, and surrounding areas.
, 2. Which Minnesota agency oversees statewide SSTS regulations?
A. Minnesota Department of Transportation
B. Minnesota Department of Natural Resources
C. Minnesota Pollution Control Agency
D. Minnesota Department of Agriculture
Answer: C. Minnesota Pollution Control Agency
The Minnesota Pollution Control Agency establishes statewide SSTS rules
and standards that local authorities use for regulation and enforcement.
3. A compliant septic system must primarily prevent:
A. Soil erosion only
B. Sewage discharge and public exposure risks
C. Rainwater collection
D. Building foundation movement
Answer: B. Sewage discharge and public exposure risks
A properly functioning SSTS treats wastewater and prevents untreated
sewage from reaching people, groundwater, or surface waters.
4. During an inspection, the first step should usually be:
A. Pumping the tank immediately
B. Reviewing available records and system information
,C. Removing the drainfield soil
D. Replacing the distribution box
Answer: B. Reviewing available records and system information
Inspectors begin by gathering information such as permits, previous
inspections, and system design details before field evaluation.
5. The septic tank’s main function is to:
A. Completely disinfect wastewater
B. Separate solids and allow primary treatment
C. Pump wastewater directly into soil
D. Increase groundwater levels
Answer: B. Separate solids and allow primary treatment
The septic tank allows solids to settle, scum to float, and partially treated
effluent to move to the next treatment stage.
6. Which condition indicates a potential SSTS failure?
A. Properly functioning absorption area
B. Sewage surfacing on the ground
C. Regular maintenance pumping
D. Proper tank access covers
Answer: B. Sewage surfacing on the ground
, Sewage surfacing indicates inadequate treatment or hydraulic failure and
creates a direct public health concern.
7. The drainfield treats wastewater mainly through:
A. Chemical additives
B. Soil filtration and biological activity
C. Chlorination only
D. Mechanical screening
Answer: B. Soil filtration and biological activity
The soil beneath the drainfield provides treatment by filtering particles and
supporting microorganisms that break down contaminants.
8. A septic tank inspection should include checking:
A. Tank integrity and liquid levels
B. Roof structure
C. Electrical wiring only
D. Interior plumbing fixtures only
Answer: A. Tank integrity and liquid levels
Inspectors evaluate the tank for leaks, damage, proper liquid levels, and
evidence of hydraulic problems.
9. What is the purpose of septic tank baffles?
