PRACTICE EXAM – SCDES 2026/2027 EDITION
350 MULTIPLE-CHOICE QUESTIONS WITH
ANSWERS AND RATIONALES
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SECTION 1: REGULATORY AUTHORITY & GENERAL PROVISIONS (Questions
1–35)
Question 1
Which South Carolina state agency currently oversees the licensing and
regulation of onsite wastewater systems and contractors?
A) South Carolina Department of Labor, Licensing and Regulation (LLR)
B) South Carolina Department of Health and Environmental Control (DHEC)
C) South Carolina Department of Environmental Services (SCDES)
D) South Carolina Department of Natural Resources (SCDNR)
Answer: C
Rationale: As of July 1, 2024, the former SCDHEC was reorganized, and
environmental permitting and enforcement functions—including Regulation
61-56—were transferred to the newly established South Carolina Department
of Environmental Services (SCDES).
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,Question 2
Which specific South Carolina regulation governs the design, installation, and
maintenance of septic tanks?
A) Regulation 61-51 (Standards for Swimming Pools)
B) Regulation 61-56 (Onsite Wastewater Systems)
C) Regulation 61-67 (Solid Waste Management)
D) Regulation 61-25 (Retail Food Establishments)
Answer: B
Rationale: Regulation 61-56 is titled "Onsite Wastewater Systems" and serves
as the exclusive authority for onsite wastewater treatment and disposal
systems in South Carolina.
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Question 3
What is the minimum passing score required for the South Carolina septic
tank contractor licensing examination?
A) 70%
B) 75%
C) 80%
D) 90%
Answer: C
Rationale: Candidates must achieve a score of 80% or better to pass the
licensure exam. Failure requires a 30-day wait before a retake.
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Question 4
How long is a septic system construction permit valid from the date of
issuance in South Carolina?
A) 6 months
B) 1 year
C) 3 years
D) 5 years
Answer: C
Rationale: Permits typically expire after 3 years if construction has not
commenced or if no substantial progress has been made. This ensures site
conditions are re-evaluated.
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Question 5
A Tier 1 Installer license authorizes a contractor to perform which type of
work?
A) Installation of pressurized sewage systems
B) Installation of all gravity-fed residential onsite wastewater systems
C) Major repairs to existing failing drainfields
D) Soil classification without supervision
Answer: B
, Rationale: Tier 1 is the entry-level classification limited strictly to installing
new gravity-fed residential onsite wastewater systems. Repairs and
pressurized systems require higher tiers.
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Question 6
Which of the following is the primary purpose of a septic tank in an onsite
wastewater system?
A) To distribute effluent to the soil
B) To disinfect wastewater
C) To separate solids from liquids and provide primary treatment
D) To aerate wastewater
Answer: C
Rationale: The septic tank's main function is to settle solids (sludge and scum)
and allow anaerobic digestion before effluent leaves the tank for the
drainfield.
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Question 7
What is the minimum horizontal setback distance between a septic tank and a
private water well in South Carolina?
A) 25 feet
B) 50 feet
C) 75 feet