South Carolina (SC) Septic Tank Contractor Practice
Exam 2026-2027 /250 Questions with Answers and
Detailed Rationales
Introduction
This comprehensive 250-question practice exam is designed to prepare candidates for
the South Carolina Septic Tank Contractor licensing exam. The exam is administered
by the SC Department of Environmental Services (SCDES) —formerly DHEC—and
requires a passing score of 80% or better .
All questions are based on SC Regulation 61-56 (Onsite Wastewater Systems) , the
primary governing regulation for septic systems in South Carolina . Topics covered
include:
Regulatory requirements (permits, setbacks, inspections)
Soil science and site evaluation (perc tests, deep holes, soil morphology)
System components and design (tanks, drainfields, alternative systems)
Installation and construction (trenching, backfilling, inspections)
Maintenance and troubleshooting (pumping schedules, failure causes)
Licensing requirements (tiers, renewal, professional conduct)
Section 1: Regulatory Authority & General Provisions
(Questions 1-20)
1. What is the primary authority for regulating septic systems in South Carolina?
A) South Carolina Department of Natural Resources (SCDNR)
B) South Carolina Department of Environmental Services (SCDES)
C) South Carolina Department of Commerce
D) Local county governments only
,Answer: B) South Carolina Department of Environmental Services (SCDES)
Rationale: The South Carolina Department of Environmental Services (SCDES) is
responsible for regulating and overseeing septic systems in South Carolina, including
permitting, inspections, and compliance with Regulation 61-56. This authority was
previously held by DHEC before the agency reorganization .
2. Which South Carolina regulation specifically governs onsite wastewater
systems?
A) Regulation 61-58 (State Primary Drinking Water Regulations)
B) Regulation 61-67 (Solid Waste Management)
C) Regulation 61-56 (Onsite Wastewater Systems)
D) Regulation 61-100 (Hazardous Waste Management)
*Answer: C) Regulation 61-56 (Onsite Wastewater Systems)*
Rationale: Regulation 61-56 is titled "Onsite Wastewater Systems" and serves as the
primary regulatory framework for septic system design, installation, and maintenance in
South Carolina. All contractors must be familiar with its provisions .
3. According to R.61-56.103, each dwelling or business occupied for more than
how many hours per day must have an approved wastewater treatment method?
A) 1 hour
B) 2 hours
C) 4 hours
D) 8 hours
Answer: B) 2 hours
Rationale: Section 103.1(1) of Regulation 61-56 states: "Each dwelling, business, or other
structure occupied for more than two (2) hours per day shall be provided with an
approved method for the treatment and disposal of domestic wastewater" .
,4. Who is responsible for ensuring a permit to construct is obtained before
building a new septic system?
A) The septic tank contractor
B) The local county inspector
C) The property owner
D) The general contractor
Answer: C) The property owner
Rationale: According to R.61-56.103(2), "It shall be the responsibility of the property
owner to ensure that a permit to construct and operate any new, upgraded, or
expanded onsite wastewater system... is obtained from the Department prior to
construction" .
5. Can a mobile or modular home be moved onto a site before a septic permit is
issued?
A) Yes, if a temporary holding tank is used
B) Yes, with written approval from the property owner
C) No, the permit must be issued first
D) Yes, as long as the home is not occupied
Answer: C) No, the permit must be issued first
Rationale: R.61-56.103(3) explicitly states: "Mobile or modular structures intended for
occupancy shall not be moved onto the site until the permit to construct and operate an
onsite wastewater system has been issued" .
6. What is the minimum passing score for the SC Septic Tank Contractor licensing
exam?
, A) 70%
B) 75%
C) 80%
D) 85%
Answer: C) 80%
Rationale: According to SCDES licensing requirements, applicants must score 80% or
better to pass the exam. If a candidate fails, they may retake it in 30 days. A second
failure requires a 60-day wait before a third attempt .
7. How often must a septic tank contractor license be renewed in South Carolina?
A) Every year
B) Every 2 years
C) Every 3 years
D) Every 5 years
Answer: A) Every year
Rationale: Septic system professionals must renew their license annually and pay the
required renewal fees. If a license expires and is not renewed within 90 days of the due
date (including late fees), the licensee must repeat the entire new license process from
the beginning .
8. What is the annual renewal fee for a Tier 1 Installer license in SC?
A) $50
B) $100
C) $150
D) $200
Answer: B) $100
Exam 2026-2027 /250 Questions with Answers and
Detailed Rationales
Introduction
This comprehensive 250-question practice exam is designed to prepare candidates for
the South Carolina Septic Tank Contractor licensing exam. The exam is administered
by the SC Department of Environmental Services (SCDES) —formerly DHEC—and
requires a passing score of 80% or better .
All questions are based on SC Regulation 61-56 (Onsite Wastewater Systems) , the
primary governing regulation for septic systems in South Carolina . Topics covered
include:
Regulatory requirements (permits, setbacks, inspections)
Soil science and site evaluation (perc tests, deep holes, soil morphology)
System components and design (tanks, drainfields, alternative systems)
Installation and construction (trenching, backfilling, inspections)
Maintenance and troubleshooting (pumping schedules, failure causes)
Licensing requirements (tiers, renewal, professional conduct)
Section 1: Regulatory Authority & General Provisions
(Questions 1-20)
1. What is the primary authority for regulating septic systems in South Carolina?
A) South Carolina Department of Natural Resources (SCDNR)
B) South Carolina Department of Environmental Services (SCDES)
C) South Carolina Department of Commerce
D) Local county governments only
,Answer: B) South Carolina Department of Environmental Services (SCDES)
Rationale: The South Carolina Department of Environmental Services (SCDES) is
responsible for regulating and overseeing septic systems in South Carolina, including
permitting, inspections, and compliance with Regulation 61-56. This authority was
previously held by DHEC before the agency reorganization .
2. Which South Carolina regulation specifically governs onsite wastewater
systems?
A) Regulation 61-58 (State Primary Drinking Water Regulations)
B) Regulation 61-67 (Solid Waste Management)
C) Regulation 61-56 (Onsite Wastewater Systems)
D) Regulation 61-100 (Hazardous Waste Management)
*Answer: C) Regulation 61-56 (Onsite Wastewater Systems)*
Rationale: Regulation 61-56 is titled "Onsite Wastewater Systems" and serves as the
primary regulatory framework for septic system design, installation, and maintenance in
South Carolina. All contractors must be familiar with its provisions .
3. According to R.61-56.103, each dwelling or business occupied for more than
how many hours per day must have an approved wastewater treatment method?
A) 1 hour
B) 2 hours
C) 4 hours
D) 8 hours
Answer: B) 2 hours
Rationale: Section 103.1(1) of Regulation 61-56 states: "Each dwelling, business, or other
structure occupied for more than two (2) hours per day shall be provided with an
approved method for the treatment and disposal of domestic wastewater" .
,4. Who is responsible for ensuring a permit to construct is obtained before
building a new septic system?
A) The septic tank contractor
B) The local county inspector
C) The property owner
D) The general contractor
Answer: C) The property owner
Rationale: According to R.61-56.103(2), "It shall be the responsibility of the property
owner to ensure that a permit to construct and operate any new, upgraded, or
expanded onsite wastewater system... is obtained from the Department prior to
construction" .
5. Can a mobile or modular home be moved onto a site before a septic permit is
issued?
A) Yes, if a temporary holding tank is used
B) Yes, with written approval from the property owner
C) No, the permit must be issued first
D) Yes, as long as the home is not occupied
Answer: C) No, the permit must be issued first
Rationale: R.61-56.103(3) explicitly states: "Mobile or modular structures intended for
occupancy shall not be moved onto the site until the permit to construct and operate an
onsite wastewater system has been issued" .
6. What is the minimum passing score for the SC Septic Tank Contractor licensing
exam?
, A) 70%
B) 75%
C) 80%
D) 85%
Answer: C) 80%
Rationale: According to SCDES licensing requirements, applicants must score 80% or
better to pass the exam. If a candidate fails, they may retake it in 30 days. A second
failure requires a 60-day wait before a third attempt .
7. How often must a septic tank contractor license be renewed in South Carolina?
A) Every year
B) Every 2 years
C) Every 3 years
D) Every 5 years
Answer: A) Every year
Rationale: Septic system professionals must renew their license annually and pay the
required renewal fees. If a license expires and is not renewed within 90 days of the due
date (including late fees), the licensee must repeat the entire new license process from
the beginning .
8. What is the annual renewal fee for a Tier 1 Installer license in SC?
A) $50
B) $100
C) $150
D) $200
Answer: B) $100
