MISSISSIPPI INDIVIDUAL ONSITE WASTEWATER
INSTALLER LICENSING EXAMINATION COMPLETE
QUESTIONS AND DETAILED SOLUTIONS LATEST
UPDATE THIS YEAR JUST RELEASED
Exam Coverage Areas — Short Summary
1. Mississippi Onsite Wastewater Regulations and Licensing — Understand installer
licensing requirements, regulatory responsibilities, permits, inspections, enforcement,
and applicable Mississippi Department of Environmental Quality (MDEQ) requirements.
2. Site Evaluation and Soil Characteristics — Assess soil texture, structure, restrictive
layers, groundwater conditions, seasonal saturation, and site limitations affecting onsite
wastewater system suitability.
3. System Siting and Setbacks — Know required separation distances from wells, property
boundaries, buildings, surface waters, drainage features, and other environmental or
structural constraints.
4. Septic Tank Design and Installation — Understand tank sizing, watertight construction,
inlet and outlet arrangements, access openings, baffles, risers, installation procedures,
and inspection requirements.
5. Effluent Disposal and Absorption Systems — Master conventional absorption trenches,
beds, mound-type systems, pressure distribution, dosing systems, and appropriate
application based on site conditions.
6. Hydraulic and Loading Considerations — Calculate wastewater flows, design daily
loading, distribution requirements, trench dimensions, dosing volumes, and system
capacity.
7. Pumps, Dosing Chambers, and Electrical Components — Understand pump selection,
controls, floats, alarms, dosing cycles, electrical safety, watertight connections, and
maintenance access.
8. Construction Practices and Quality Control — Apply proper excavation, bedding, pipe
installation, aggregate placement, grading, backfilling, compaction, and protection of
soil infiltrative surfaces.
9. System Operation, Maintenance, and Troubleshooting — Recognize causes of backups,
ponding, surfacing effluent, hydraulic overload, clogged components, pump failures, and
inadequate maintenance.
, 10. Environmental Protection, Public Health, and Installer Safety — Prevent groundwater
and surface-water contamination while following safe work practices involving
excavations, confined spaces, sewage exposure, equipment, and electrical hazards.
Question 1
Which primary objective should an installer prioritize when designing and constructing
an onsite wastewater treatment system for a residential property?
A. Minimizing the amount of excavation regardless of soil conditions
B. Protecting public health and preventing contamination of groundwater and surface
water
C. Eliminating all required inspections after installation
D. Maximizing the number of wastewater fixtures connected
Answer: B
Rationale: The fundamental purpose of onsite wastewater management is protecting
public health and environmental quality. Proper treatment and dispersal prevent
untreated sewage from reaching people, groundwater, or surface water.
Question 2
Before beginning construction of an individual onsite wastewater system, what
regulatory action is generally required to ensure the proposed installation is authorized?
A. Obtain appropriate approval or permit from the responsible regulatory authority
B. Begin excavation and request authorization after completing construction
C. Obtain permission only from the nearest equipment rental company
D. Install the septic tank before submitting any paperwork
Answer: A
Rationale: Regulatory approval or permitting is generally required before construction
begins. The process allows authorities to verify that the proposed system meets
applicable health and environmental requirements.
,Question 3
Why is a thorough site and soil evaluation essential before selecting the type and
location of an onsite wastewater disposal system?
A. It determines the brand of septic tank that must be purchased
B. It identifies site limitations affecting wastewater treatment and subsurface dispersal
C. It eliminates the need for calculating wastewater flows
D. It guarantees that every property can support a conventional system
Answer: B
Rationale: Soil permeability, restrictive layers, groundwater, slope, and available area
strongly influence whether wastewater can be adequately treated and dispersed.
Question 4
Which soil characteristic is especially important when determining whether wastewater
can infiltrate and receive adequate treatment beneath an absorption area?
A. Soil color alone
B. Infiltration and permeability characteristics
C. Number of trees growing nearby
D. Distance from the nearest public road
Answer: B
Rationale: Soil infiltration and permeability affect hydraulic loading and wastewater
movement. Excessively rapid or slow movement can create treatment or hydraulic
problems.
Question 5
What is the primary function of a septic tank in a typical onsite wastewater treatment
system serving an individual residence?
A. Completely disinfect all wastewater before discharge
B. Provide primary treatment by settling solids and retaining floatable materials
, C. Pump wastewater directly into nearby surface water
D. Eliminate the need for an absorption or dispersal area
Answer: B
Rationale: Septic tanks provide primary treatment by separating solids and scum from
liquid effluent. Additional treatment and dispersal occur downstream.
Question 6
Why must a septic tank be installed with adequate access openings and properly
positioned covers during onsite wastewater construction?
A. To allow inspection, maintenance, pumping, and safe access to necessary
components
B. To increase the amount of wastewater entering the tank
C. To reduce the required tank capacity
D. To eliminate the need for outlet protection
Answer: A
Rationale: Accessible tank openings facilitate inspection and pumping. Proper covers
also help prevent unauthorized entry and protect people from dangerous conditions.
Question 7
What is the primary purpose of an inlet baffle or comparable inlet arrangement within a
properly designed septic tank?
A. To prevent incoming wastewater from excessively disturbing settled solids
B. To increase the velocity of wastewater leaving the tank
C. To force solids into the absorption field
D. To replace the need for a septic tank outlet
Answer: A
Rationale: The inlet arrangement helps direct incoming wastewater into the tank while
minimizing disturbance of settled sludge and scum layers.
INSTALLER LICENSING EXAMINATION COMPLETE
QUESTIONS AND DETAILED SOLUTIONS LATEST
UPDATE THIS YEAR JUST RELEASED
Exam Coverage Areas — Short Summary
1. Mississippi Onsite Wastewater Regulations and Licensing — Understand installer
licensing requirements, regulatory responsibilities, permits, inspections, enforcement,
and applicable Mississippi Department of Environmental Quality (MDEQ) requirements.
2. Site Evaluation and Soil Characteristics — Assess soil texture, structure, restrictive
layers, groundwater conditions, seasonal saturation, and site limitations affecting onsite
wastewater system suitability.
3. System Siting and Setbacks — Know required separation distances from wells, property
boundaries, buildings, surface waters, drainage features, and other environmental or
structural constraints.
4. Septic Tank Design and Installation — Understand tank sizing, watertight construction,
inlet and outlet arrangements, access openings, baffles, risers, installation procedures,
and inspection requirements.
5. Effluent Disposal and Absorption Systems — Master conventional absorption trenches,
beds, mound-type systems, pressure distribution, dosing systems, and appropriate
application based on site conditions.
6. Hydraulic and Loading Considerations — Calculate wastewater flows, design daily
loading, distribution requirements, trench dimensions, dosing volumes, and system
capacity.
7. Pumps, Dosing Chambers, and Electrical Components — Understand pump selection,
controls, floats, alarms, dosing cycles, electrical safety, watertight connections, and
maintenance access.
8. Construction Practices and Quality Control — Apply proper excavation, bedding, pipe
installation, aggregate placement, grading, backfilling, compaction, and protection of
soil infiltrative surfaces.
9. System Operation, Maintenance, and Troubleshooting — Recognize causes of backups,
ponding, surfacing effluent, hydraulic overload, clogged components, pump failures, and
inadequate maintenance.
, 10. Environmental Protection, Public Health, and Installer Safety — Prevent groundwater
and surface-water contamination while following safe work practices involving
excavations, confined spaces, sewage exposure, equipment, and electrical hazards.
Question 1
Which primary objective should an installer prioritize when designing and constructing
an onsite wastewater treatment system for a residential property?
A. Minimizing the amount of excavation regardless of soil conditions
B. Protecting public health and preventing contamination of groundwater and surface
water
C. Eliminating all required inspections after installation
D. Maximizing the number of wastewater fixtures connected
Answer: B
Rationale: The fundamental purpose of onsite wastewater management is protecting
public health and environmental quality. Proper treatment and dispersal prevent
untreated sewage from reaching people, groundwater, or surface water.
Question 2
Before beginning construction of an individual onsite wastewater system, what
regulatory action is generally required to ensure the proposed installation is authorized?
A. Obtain appropriate approval or permit from the responsible regulatory authority
B. Begin excavation and request authorization after completing construction
C. Obtain permission only from the nearest equipment rental company
D. Install the septic tank before submitting any paperwork
Answer: A
Rationale: Regulatory approval or permitting is generally required before construction
begins. The process allows authorities to verify that the proposed system meets
applicable health and environmental requirements.
,Question 3
Why is a thorough site and soil evaluation essential before selecting the type and
location of an onsite wastewater disposal system?
A. It determines the brand of septic tank that must be purchased
B. It identifies site limitations affecting wastewater treatment and subsurface dispersal
C. It eliminates the need for calculating wastewater flows
D. It guarantees that every property can support a conventional system
Answer: B
Rationale: Soil permeability, restrictive layers, groundwater, slope, and available area
strongly influence whether wastewater can be adequately treated and dispersed.
Question 4
Which soil characteristic is especially important when determining whether wastewater
can infiltrate and receive adequate treatment beneath an absorption area?
A. Soil color alone
B. Infiltration and permeability characteristics
C. Number of trees growing nearby
D. Distance from the nearest public road
Answer: B
Rationale: Soil infiltration and permeability affect hydraulic loading and wastewater
movement. Excessively rapid or slow movement can create treatment or hydraulic
problems.
Question 5
What is the primary function of a septic tank in a typical onsite wastewater treatment
system serving an individual residence?
A. Completely disinfect all wastewater before discharge
B. Provide primary treatment by settling solids and retaining floatable materials
, C. Pump wastewater directly into nearby surface water
D. Eliminate the need for an absorption or dispersal area
Answer: B
Rationale: Septic tanks provide primary treatment by separating solids and scum from
liquid effluent. Additional treatment and dispersal occur downstream.
Question 6
Why must a septic tank be installed with adequate access openings and properly
positioned covers during onsite wastewater construction?
A. To allow inspection, maintenance, pumping, and safe access to necessary
components
B. To increase the amount of wastewater entering the tank
C. To reduce the required tank capacity
D. To eliminate the need for outlet protection
Answer: A
Rationale: Accessible tank openings facilitate inspection and pumping. Proper covers
also help prevent unauthorized entry and protect people from dangerous conditions.
Question 7
What is the primary purpose of an inlet baffle or comparable inlet arrangement within a
properly designed septic tank?
A. To prevent incoming wastewater from excessively disturbing settled solids
B. To increase the velocity of wastewater leaving the tank
C. To force solids into the absorption field
D. To replace the need for a septic tank outlet
Answer: A
Rationale: The inlet arrangement helps direct incoming wastewater into the tank while
minimizing disturbance of settled sludge and scum layers.
