CPESC Erosion Control Methods & Techniques 3

Question 1

A level spreader is used in stormwater management to:

Accepted Answer

Convert concentrated flow into sheet flow before entering a vegetated filter

Answer

A level spreader distributes concentrated channel flow evenly across its full length, converting it to sheet flow for treatment by a vegetated filter strip.

Question 2

When installing silt fence on a slope, the bottom of the fence fabric should be:

Accepted Answer

Folded outward (upstream) and buried at least 6 inches in a trench

Answer

Burying the toe of the fabric in a trench prevents undercutting and ensures runoff must pass through the filter fabric.

Question 3

Runoff from steep erodible slopes is best managed by intercepting it before it accelerates using:

Accepted Answer

Diversions and interceptor drains across the slope

Answer

Interceptor drains and diversions capture runoff before it gains velocity, preventing rill and gully formation on steep slopes.

Question 4

Which seeding technique is best suited for steep rocky slopes where conventional drill seeding is impractical?

Accepted Answer

Hydroseeding with wood fiber mulch and tackifier

Answer

Hydroseeding applies seed, mulch, and tackifier in a slurry that can reach inaccessible steep and rocky slopes while anchoring seed in place.

Question 5

The concept of 'soil loss tolerance' (T value) in erosion control represents:

Accepted Answer

The maximum annual soil loss rate at which soil productivity can be maintained indefinitely

Answer

T value represents the maximum rate of soil erosion that can occur while maintaining long-term soil productivity, typically 1–5 tons/acre/year.

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

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

CPESC Erosion Control Methods & Techniques 3