SOUTH CAROLINA SEPTIC TANK
INSTALLER LICENSE EXAM 2026/2027 –
COMPLETE 300 REAL EXAM
QUESTIONS WITH VERIFIED ANSWERS
& DETAILED RATIONALES | SCDES
REGULATION 61-56 | TIER 1, TIER 2,
TIER 3 | ALREADY GRADED A+ |
INSTANT DOWNLOAD PDF
Section 1: Licensing, Regulations & Permitting
1. Which South Carolina agency is responsible for regulating onsite wastewater
systems and licensing septic tank contractors?
A) South Carolina Department of Labor, Licensing and Regulation (LLR)
B) South Carolina Department of Environmental Services (SCDES)
C) South Carolina Department of Natural Resources (DNR)
D) U.S. Environmental Protection Agency (EPA)
Correct Answer: B.Rationale: As of July 1, 2024, the environmental permitting and
enforcement functions (including R.61-56) were transferred to the newly established
SCDES. SCDES is the sole issuing authority for septic tank contractor licenses.
2. What is the minimum passing score required for the South Carolina septic
tank contractor licensing examination?
A) 70%
B) 75%
C) 80%
D) 85%
Correct Answer: C.Rationale: First-time applicants must pass the Regulation 61-56
exam with a score of 80% or better. The exam covers design, installation, and
maintenance of onsite wastewater systems.
,3. Which specific state regulation governs the design, installation, and
maintenance of septic tanks in South Carolina?
A) R.61-51 (Standards for Swimming Pools)
B) R.61-56 (Onsite Wastewater Systems)
C) R.61-67 (Solid Waste Management)
D) R.61-25 (Retail Food Establishments)
Correct Answer: B.Rationale: Regulation 61-56 is the exclusive authority for onsite
wastewater treatment and disposal systems in South Carolina.
4. A Tier 1 Installer license allows you to perform which of the following tasks?
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
Correct Answer: B.Rationale: Tier 1 is the entry-level license for new gravity-fed
residential systems. Repairs (Tier 2) and pressurized/commercial systems (Tier 3)
require higher licensure levels.
5. What is the minimum bond amount required for septic installers in South
Carolina?
A) $5,000
B) $10,000
C) $15,000
D) $25,000
Correct Answer: B.Rationale: The bond amount required for septic installers is a
minimum of $10,000, covering project costs and adjustable for large jobs.
6. How often must a Tier 1 Installer renew their license with SCDES?
A) Annually
B) Every 2 years
C) Every 3 years
D) Every 5 years
Correct Answer: A.Rationale: Licenses for installers and haulers must be renewed
annually and are subject to late fees if not paid on time.
7. If a contractor fails a licensing exam, when can they retake it?
A) The next day
B) 30 days later
C) 6 months later
D) 1 year later
,Correct Answer: B.Rationale: After the first fail, the applicant must wait 30 days
before retaking. A second fail requires a 60-day wait, but there is no limit on total
attempts.
8. Which South Carolina installer tier is authorized to install all gravity-fed
residential onsite wastewater systems?
A) Apprentice Installer
B) Tier 1 Installer
C) Tier 2 Installer
D) Tier 3 Installer
Correct Answer: B.Rationale: Tier 1 installers are authorized to install gravity-fed
residential systems within their permitted scope. Tier 2 and Tier 3 installers have
broader authority.
9. A licensed installer wants to install a system requiring a pump and a curtain
drain. Which is the minimum installer tier generally authorized for this work?
A) Tier 1
B) Tier 2
C) Tier 3 only
D) Unlicensed contractor
Correct Answer: B.Rationale: Tier 2 includes systems requiring pumps and curtain
drains in addition to the systems authorized for Tier 1. Tier 3 is not required solely
because a system contains these features.
10. Which installer tier is authorized to install Standard 610 Specialized Onsite
Wastewater Systems?
A) Tier 1
B) Tier 2
C) Tier 3
D) Any licensed installer
Correct Answer: C.Rationale: Tier 3 encompasses Tier 1 and Tier 2 installation
authority and adds Standard 610 Specialized Onsite Wastewater Systems. Tier 1 and
Tier 2 installers do not have that specialized-system authority.
11. A Tier 1 installer is asked to repair an existing onsite wastewater system.
What is the most appropriate response?
A) Proceed because Tier 1 covers all residential systems
B) Proceed if the homeowner signs a waiver
C) Proceed only if the system is gravity-fed
D) Refer the repair to an installer with the required repair authority
, Correct Answer: D.Rationale: Tier 1 installation authority does not include repairs to
existing onsite wastewater systems. Tier 2 has authority to conduct repairs.
12. Which statement best describes a Tier 2 installer's scope?
A) Only gravity-fed residential systems
B) Only engineered systems
C) Tier 1 systems plus specified pump, commercial, and other systems within Tier 2
authority
D) All systems, including every Standard 610 system
Correct Answer: C.Rationale: Tier 2 expands upon Tier 1 to include pumps, grease
traps, curtain drains, elevated infiltration systems, mounded systems, and specified
commercial and larger systems. Standard 610 specialized systems are associated with
Tier 3 authority.
13. A person applying for Tier 3 licensure has been actively installing in South
Carolina for the required period but has a disqualifying prior onsite wastewater
disciplinary history. Which issue is most directly relevant?
A) The applicant's tank manufacturer
B) The applicant's vehicle capacity
C) The applicant's eligibility based on disciplinary history
D) The applicant's residential water-use estimate
Correct Answer: C.Rationale: Tier 3 eligibility includes experience requirements and
the absence of pending or prior disciplinary or enforcement action involving onsite
wastewater system contracting.
14. An applicant licensed as an installer in another state seeks South Carolina
Tier 3 eligibility. Which experience documentation is particularly relevant?
A) A letter from a supplier
B) Affidavits from the regulatory authority demonstrating five years of experience
C) A copy of a driver's license
D) A residential utility bill
Correct Answer: B.Rationale: An onsite wastewater system installer licensee from
another state can apply for Tier 3 with affidavits from the regulatory authority
demonstrating five years of experience with no pending or prior disciplinary action.
15. Which condition is most important when determining whether a proposed
site can support a conventional onsite wastewater system?
A) The color of the house exterior
B) The property's assessed value
C) Soil conditions and depth to seasonal high water table
D) The number of trees on the property
INSTALLER LICENSE EXAM 2026/2027 –
COMPLETE 300 REAL EXAM
QUESTIONS WITH VERIFIED ANSWERS
& DETAILED RATIONALES | SCDES
REGULATION 61-56 | TIER 1, TIER 2,
TIER 3 | ALREADY GRADED A+ |
INSTANT DOWNLOAD PDF
Section 1: Licensing, Regulations & Permitting
1. Which South Carolina agency is responsible for regulating onsite wastewater
systems and licensing septic tank contractors?
A) South Carolina Department of Labor, Licensing and Regulation (LLR)
B) South Carolina Department of Environmental Services (SCDES)
C) South Carolina Department of Natural Resources (DNR)
D) U.S. Environmental Protection Agency (EPA)
Correct Answer: B.Rationale: As of July 1, 2024, the environmental permitting and
enforcement functions (including R.61-56) were transferred to the newly established
SCDES. SCDES is the sole issuing authority for septic tank contractor licenses.
2. What is the minimum passing score required for the South Carolina septic
tank contractor licensing examination?
A) 70%
B) 75%
C) 80%
D) 85%
Correct Answer: C.Rationale: First-time applicants must pass the Regulation 61-56
exam with a score of 80% or better. The exam covers design, installation, and
maintenance of onsite wastewater systems.
,3. Which specific state regulation governs the design, installation, and
maintenance of septic tanks in South Carolina?
A) R.61-51 (Standards for Swimming Pools)
B) R.61-56 (Onsite Wastewater Systems)
C) R.61-67 (Solid Waste Management)
D) R.61-25 (Retail Food Establishments)
Correct Answer: B.Rationale: Regulation 61-56 is the exclusive authority for onsite
wastewater treatment and disposal systems in South Carolina.
4. A Tier 1 Installer license allows you to perform which of the following tasks?
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
Correct Answer: B.Rationale: Tier 1 is the entry-level license for new gravity-fed
residential systems. Repairs (Tier 2) and pressurized/commercial systems (Tier 3)
require higher licensure levels.
5. What is the minimum bond amount required for septic installers in South
Carolina?
A) $5,000
B) $10,000
C) $15,000
D) $25,000
Correct Answer: B.Rationale: The bond amount required for septic installers is a
minimum of $10,000, covering project costs and adjustable for large jobs.
6. How often must a Tier 1 Installer renew their license with SCDES?
A) Annually
B) Every 2 years
C) Every 3 years
D) Every 5 years
Correct Answer: A.Rationale: Licenses for installers and haulers must be renewed
annually and are subject to late fees if not paid on time.
7. If a contractor fails a licensing exam, when can they retake it?
A) The next day
B) 30 days later
C) 6 months later
D) 1 year later
,Correct Answer: B.Rationale: After the first fail, the applicant must wait 30 days
before retaking. A second fail requires a 60-day wait, but there is no limit on total
attempts.
8. Which South Carolina installer tier is authorized to install all gravity-fed
residential onsite wastewater systems?
A) Apprentice Installer
B) Tier 1 Installer
C) Tier 2 Installer
D) Tier 3 Installer
Correct Answer: B.Rationale: Tier 1 installers are authorized to install gravity-fed
residential systems within their permitted scope. Tier 2 and Tier 3 installers have
broader authority.
9. A licensed installer wants to install a system requiring a pump and a curtain
drain. Which is the minimum installer tier generally authorized for this work?
A) Tier 1
B) Tier 2
C) Tier 3 only
D) Unlicensed contractor
Correct Answer: B.Rationale: Tier 2 includes systems requiring pumps and curtain
drains in addition to the systems authorized for Tier 1. Tier 3 is not required solely
because a system contains these features.
10. Which installer tier is authorized to install Standard 610 Specialized Onsite
Wastewater Systems?
A) Tier 1
B) Tier 2
C) Tier 3
D) Any licensed installer
Correct Answer: C.Rationale: Tier 3 encompasses Tier 1 and Tier 2 installation
authority and adds Standard 610 Specialized Onsite Wastewater Systems. Tier 1 and
Tier 2 installers do not have that specialized-system authority.
11. A Tier 1 installer is asked to repair an existing onsite wastewater system.
What is the most appropriate response?
A) Proceed because Tier 1 covers all residential systems
B) Proceed if the homeowner signs a waiver
C) Proceed only if the system is gravity-fed
D) Refer the repair to an installer with the required repair authority
, Correct Answer: D.Rationale: Tier 1 installation authority does not include repairs to
existing onsite wastewater systems. Tier 2 has authority to conduct repairs.
12. Which statement best describes a Tier 2 installer's scope?
A) Only gravity-fed residential systems
B) Only engineered systems
C) Tier 1 systems plus specified pump, commercial, and other systems within Tier 2
authority
D) All systems, including every Standard 610 system
Correct Answer: C.Rationale: Tier 2 expands upon Tier 1 to include pumps, grease
traps, curtain drains, elevated infiltration systems, mounded systems, and specified
commercial and larger systems. Standard 610 specialized systems are associated with
Tier 3 authority.
13. A person applying for Tier 3 licensure has been actively installing in South
Carolina for the required period but has a disqualifying prior onsite wastewater
disciplinary history. Which issue is most directly relevant?
A) The applicant's tank manufacturer
B) The applicant's vehicle capacity
C) The applicant's eligibility based on disciplinary history
D) The applicant's residential water-use estimate
Correct Answer: C.Rationale: Tier 3 eligibility includes experience requirements and
the absence of pending or prior disciplinary or enforcement action involving onsite
wastewater system contracting.
14. An applicant licensed as an installer in another state seeks South Carolina
Tier 3 eligibility. Which experience documentation is particularly relevant?
A) A letter from a supplier
B) Affidavits from the regulatory authority demonstrating five years of experience
C) A copy of a driver's license
D) A residential utility bill
Correct Answer: B.Rationale: An onsite wastewater system installer licensee from
another state can apply for Tier 3 with affidavits from the regulatory authority
demonstrating five years of experience with no pending or prior disciplinary action.
15. Which condition is most important when determining whether a proposed
site can support a conventional onsite wastewater system?
A) The color of the house exterior
B) The property's assessed value
C) Soil conditions and depth to seasonal high water table
D) The number of trees on the property
