CSM CSM Erosion & Sediment Control 2

Question 1

What is the maximum recommended drainage area for a standard silt fence installation?

Accepted Answer

0.25 acres per 100 feet of fence

Answer

Industry guidance limits silt fence drainage area to approximately 0.25 acres per 100 linear feet to prevent overtopping and structural failure during storm events.

Question 2

What is the primary use of fiber rolls (wattles) in erosion and sediment control?

Accepted Answer

To intercept slope runoff and capture sediment along the contour of a disturbed slope

Answer

Fiber rolls are placed along contours on disturbed slopes to slow runoff velocity, spread flow, and trap sediment moving downslope.

Question 3

What is turbidity and why is it a key indicator in stormwater management?

Accepted Answer

Cloudiness of water caused by suspended particles; high turbidity indicates sediment pollution and can harm aquatic life

Answer

Turbidity measures water cloudiness from suspended sediment and other particles; elevated turbidity in receiving waters harms aquatic ecosystems and is often regulated under NPDES permits.

Question 4

What is the fundamental difference between erosion and sedimentation?

Accepted Answer

Erosion is the detachment and transport of soil particles; sedimentation is the deposition of those transported particles

Answer

Erosion detaches soil particles from the ground surface through water or wind energy, while sedimentation is the settling and deposition of those transported particles at a new location.

Question 5

According to general NPDES Construction General Permit requirements, how often must sediment controls be inspected?

Accepted Answer

At least every 7 days and within 24 hours after a storm event of 0.5 inches or more

Answer

Most Construction General Permits require inspections at least every 7 calendar days and within 24 hours after qualifying storm events to ensure controls are functioning properly.

(CSM) Certified Stormwater Manager Practice Test

(CSM) Certified Stormwater Manager Practice Test

CSM CSM Erosion & Sediment Control 2