Practice Exam
1. Which agency regulates septic systems in South Carolina?
A. EPA
B. OSHA
C. SC DHEC
D. USDA
Correct Answer: C
SC DHEC is the authority responsible for permitting, inspection, and enforcement of onsite
wastewater systems.
2. A septic system is primarily designed to:
A. Store wastewater indefinitely
B. Treat and dispose of wastewater safely
C. Evaporate sewage
D. Pump wastewater to rivers
Correct Answer: B
Septic systems provide primary treatment and soil-based disposal of wastewater.
3. What is the minimum separation between a septic tank and a private well in
SC (typical requirement)?
A. 25 feet
B. 50 feet
C. 75 feet
D. 100 feet
Correct Answer: D
SC regulations generally require at least 100 feet of separation to protect groundwater.
4. The purpose of a soil percolation test is to determine:
,A. Soil color
B. Soil load strength
C. Soil absorption rate
D. Soil fertility
Correct Answer: C
Perc testing evaluates how quickly soil absorbs liquid, which determines system design.
5. Which soil type has the slowest percolation rate?
A. Sand
B. Loam
C. Clay
D. Gravel
Correct Answer: C
Clay soils absorb water slowly and may require alternative system designs.
6. Septic tanks are commonly made from:
A. Wood
B. Fiberglass, concrete, or plastic
C. Aluminum
D. Clay brick
Correct Answer: B
These materials are durable, watertight, and approved for wastewater containment.
7. The primary function of a septic tank baffle is to:
A. Speed up wastewater flow
B. Prevent solids from entering the drainfield
C. Add oxygen
D. Increase pressure
Correct Answer: B
Baffles retain solids and grease inside the tank, protecting the absorption field.
, 8. What happens if solids enter the drainfield?
A. Improved filtration
B. No effect
C. Clogging and failure
D. Increased flow
Correct Answer: C
Solids clog soil pores, leading to system failure.
9. A drainfield is also known as a:
A. Storage bed
B. Leach field
C. Filter pit
D. Holding area
Correct Answer: B
“Leach field” is the common term for the soil absorption system.
10. Distribution boxes are used to:
A. Store wastewater
B. Equalize flow to trenches
C. Filter solids
D. Add chemicals
Correct Answer: B
D-boxes ensure even distribution of effluent throughout the drainfield.
11. Which component allows inspection and pumping access?
A. Effluent filter
B. Riser
C. Vent pipe
D. Trench
Correct Answer: B
Risers bring access openings to ground level for maintenance.