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South Carolina (SC) Septic Tank Contractor
Practice Exam | Full Course – 2025 Edition (
Questions | Answers & Rationales)
1. Which agency regulates onsite wastewater systems in South Carolina?
A. Department of Labor, Licensing, and Regulation
B. U.S. Environmental Protection Agency (EPA)
C. South Carolina Department of Health and Environmental Control (DHEC)
D. Department of Natural Resources
EXPLANATION The SC DHEC oversees permitting, inspection, and
maintenance of all septic systems statewide.
2. A septic contractor in South Carolina must hold which type of license to install
systems?
A. Home Inspector License
B. Residential Builder License
C. Septic Tank Contractor License issued by DHEC
D. Mechanical Contractor License
EXPLANATION DHEC issues septic installer licenses specific to onsite
wastewater work.
3. Which of the following requires a new DHEC septic permit?
A. Replacing a broken riser
B. Cleaning an existing tank
C. Relocating a tank or drainfield
D. Pumping the tank
EXPLANATION Any relocation or major modification requires a new
construction permit.
4. How long is a septic system construction permit valid in South Carolina?
A. 6 months
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B. 9 months
C. 12 months
D. 24 months
EXPLANATION DHEC permits are valid for 12 months from the issue date.
5. When must the septic system be inspected by DHEC?
A. After backfill
B. After system use begins
C. Before the system is covered
D. After six months of operation
EXPLANATION Inspection must occur prior to backfilling to verify proper
installation.
6. Minimum distance between a septic tank and a private well is:
A. 25 feet
B. 50 feet
C. 75 feet
D. 100 feet
EXPLANATION DHEC regulations require a 75-foot minimum separation to
prevent groundwater contamination.
7. A contractor discovers rock layers shallower than shown on the permit. The
correct action is to:
A. Proceed carefully
B. Excavate deeper
C. Stop and contact DHEC
D. Fill with gravel
EXPLANATION Installation must stop and DHEC must reassess site conditions.
8. Which of the following systems requires an engineer’s design in South
Carolina?
A. Conventional gravity system
B. Low-pressure distribution or mound system
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C. Shallow trench system
D. Gravel trench system
EXPLANATION Engineered or alternative systems (LPP, mound, drip) require a
professional design.
9. Septic permits and site evaluations are issued based on:
A. Contractor preference
B. Property boundaries only
C. Soil evaluation and percolation rates
D. Water usage history
EXPLANATION Site-specific soil and percolation data determine system
suitability.
10. What is the penalty for installing a system without a DHEC permit?
A. Warning only
B. Verbal notice
C. Stop-work order and potential fines
D. Referral to EPA
EXPLANATION DHEC enforces stop-work orders and civil penalties for
unpermitted installations.
11. A contractor’s license may be revoked for:
A. Late payment of permit fees
B. Repeated code violations or falsifying records
C. Working during holidays
D. Installing tanks over 1,000 gallons
EXPLANATION Misrepresentation or repeated violations result in license
suspension or revocation.
12. A DHEC-issued permit must be:
A. Kept at the contractor’s office
B. Filed at the county recorder’s office
C. Posted and visible on the job site
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D. Retained only by the homeowner
EXPLANATION Permits must be accessible for inspectors at the job site.
13. DHEC’s main goal in regulating septic systems is to:
A. Control housing density
B. Protect public health and groundwater quality
C. Increase state revenue
D. Support local contractors
EXPLANATION Septic regulation protects water resources and human health.
14. What must be done before a replacement system is installed?
A. Start trenching
B. Notify the local health department
C. Obtain a replacement permit and site verification
D. Pump the old tank
EXPLANATION All replacements require site evaluation and a new permit.
15. A septic system can only be installed by:
A. The property owner
B. Any licensed plumber
C. A DHEC-licensed septic contractor
D. A landscaping company
EXPLANATION Only DHEC-licensed contractors can legally install systems in
SC.
16. Who is responsible for ensuring the system matches the approved design?
A. Homeowner
B. DHEC inspector
C. Licensed contractor
D. Local engineer
EXPLANATION The installer must follow approved plans and ensure
compliance.
South Carolina (SC) Septic Tank Contractor
Practice Exam | Full Course – 2025 Edition (
Questions | Answers & Rationales)
1. Which agency regulates onsite wastewater systems in South Carolina?
A. Department of Labor, Licensing, and Regulation
B. U.S. Environmental Protection Agency (EPA)
C. South Carolina Department of Health and Environmental Control (DHEC)
D. Department of Natural Resources
EXPLANATION The SC DHEC oversees permitting, inspection, and
maintenance of all septic systems statewide.
2. A septic contractor in South Carolina must hold which type of license to install
systems?
A. Home Inspector License
B. Residential Builder License
C. Septic Tank Contractor License issued by DHEC
D. Mechanical Contractor License
EXPLANATION DHEC issues septic installer licenses specific to onsite
wastewater work.
3. Which of the following requires a new DHEC septic permit?
A. Replacing a broken riser
B. Cleaning an existing tank
C. Relocating a tank or drainfield
D. Pumping the tank
EXPLANATION Any relocation or major modification requires a new
construction permit.
4. How long is a septic system construction permit valid in South Carolina?
A. 6 months
,2|Page
B. 9 months
C. 12 months
D. 24 months
EXPLANATION DHEC permits are valid for 12 months from the issue date.
5. When must the septic system be inspected by DHEC?
A. After backfill
B. After system use begins
C. Before the system is covered
D. After six months of operation
EXPLANATION Inspection must occur prior to backfilling to verify proper
installation.
6. Minimum distance between a septic tank and a private well is:
A. 25 feet
B. 50 feet
C. 75 feet
D. 100 feet
EXPLANATION DHEC regulations require a 75-foot minimum separation to
prevent groundwater contamination.
7. A contractor discovers rock layers shallower than shown on the permit. The
correct action is to:
A. Proceed carefully
B. Excavate deeper
C. Stop and contact DHEC
D. Fill with gravel
EXPLANATION Installation must stop and DHEC must reassess site conditions.
8. Which of the following systems requires an engineer’s design in South
Carolina?
A. Conventional gravity system
B. Low-pressure distribution or mound system
,3|Page
C. Shallow trench system
D. Gravel trench system
EXPLANATION Engineered or alternative systems (LPP, mound, drip) require a
professional design.
9. Septic permits and site evaluations are issued based on:
A. Contractor preference
B. Property boundaries only
C. Soil evaluation and percolation rates
D. Water usage history
EXPLANATION Site-specific soil and percolation data determine system
suitability.
10. What is the penalty for installing a system without a DHEC permit?
A. Warning only
B. Verbal notice
C. Stop-work order and potential fines
D. Referral to EPA
EXPLANATION DHEC enforces stop-work orders and civil penalties for
unpermitted installations.
11. A contractor’s license may be revoked for:
A. Late payment of permit fees
B. Repeated code violations or falsifying records
C. Working during holidays
D. Installing tanks over 1,000 gallons
EXPLANATION Misrepresentation or repeated violations result in license
suspension or revocation.
12. A DHEC-issued permit must be:
A. Kept at the contractor’s office
B. Filed at the county recorder’s office
C. Posted and visible on the job site
, 4|Page
D. Retained only by the homeowner
EXPLANATION Permits must be accessible for inspectors at the job site.
13. DHEC’s main goal in regulating septic systems is to:
A. Control housing density
B. Protect public health and groundwater quality
C. Increase state revenue
D. Support local contractors
EXPLANATION Septic regulation protects water resources and human health.
14. What must be done before a replacement system is installed?
A. Start trenching
B. Notify the local health department
C. Obtain a replacement permit and site verification
D. Pump the old tank
EXPLANATION All replacements require site evaluation and a new permit.
15. A septic system can only be installed by:
A. The property owner
B. Any licensed plumber
C. A DHEC-licensed septic contractor
D. A landscaping company
EXPLANATION Only DHEC-licensed contractors can legally install systems in
SC.
16. Who is responsible for ensuring the system matches the approved design?
A. Homeowner
B. DHEC inspector
C. Licensed contractor
D. Local engineer
EXPLANATION The installer must follow approved plans and ensure
compliance.
