CPESC Sediment Control Best Practices 5

Question 1

Which soil texture is generally MOST erodible under rainfall impact?

Accepted Answer

Silt loam

Answer

Silt loam soils have high erodibility (high K factor in RUSLE) because silt particles are easily detached by raindrop impact yet remain suspended in runoff rather than settling quickly.

Question 2

A vegetated filter strip is MOST effective when:

Accepted Answer

Runoff enters as uniform sheet flow across a dense vegetative buffer

Answer

Vegetated filter strips work by slowing and spreading sheet flow through dense vegetation, allowing sediment to settle and some runoff to infiltrate.

Question 3

What maintenance action should be performed on a sediment basin outlet structure after every significant storm event?

Accepted Answer

Inspect for clogging, structural damage, and verify the principal spillway is functioning

Answer

Post-storm inspection of the outlet structure ensures it is not clogged or damaged, which could cause basin failure or bypass of stored sediment.

Question 4

Which of the following is a chemical additive approved for use in treating turbid stormwater discharges from construction sites?

Accepted Answer

Anionic polyacrylamide (PAM)

Answer

Anionic PAM is widely approved for stormwater turbidity treatment at construction sites because it is non-toxic to aquatic life at application rates and effectively flocculates fine particles.

Question 5

In a sediment basin design, the 'wet storage' volume is intended to:

Accepted Answer

Provide sufficient hydraulic residence time for sediment to settle from design storm runoff

Answer

Wet storage volume is the permanent pool below the outlet that holds water long enough to allow sediment particles to settle before discharge.

(CPESC) Certified Professional in Erosion and Sediment Control Practice Test

(CPESC) Certified Professional in Erosion and Sediment Control Practice Test

CPESC Sediment Control Best Practices 5