Virginia Erosion Sediment Control Inspector
Exam
1.Erosion Impact Area: area of land NOT ASSOCIATED with a current
land- disturbing activity but contributing to sedimentation
2.How much more soil loss occurs from construction sites versus natural
soil erosion rates? Agricultural land?: 1000 times more than the average
natural soil erosion rate.
20 times more than agricultural land.
3.What are 4 erosive forand ces?:
wind water
ice
gravit
y
4.Name and define 5 stages of soil erosion.: Raindrop- 90% of total soil
erosion Sheet- the soils ability to infiltrate water is exceeded and it runs
in sheet flow (about 100 ft before concentrating), how sediment gets
transported
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8
, Rill- when sheet flow begins to concentrate, velocity and turbulence
increase, but easily repaired
Gully-when rills converge, larger than rill and usually requires heavy
equipment to repair
Channel- large volume of water increases the gully, vertical sides are
observed or for an existing streambed when structural integrity is
destroyed
5.What are the factors of rainfall impact?: Kinetic energy is dependent on
rainfall amount/intensity, raindrop diameter, and raindrop velocity
6.What are two damaging effects of rainfall impact?: Causes soil
compression which reduces infiltration
Mainly occurs in May-Sept which is when disturbance is most active
7.4 factors influencing erosion:
climate groundcover (influenced by
humans)
soil properties
topography (influenced by humans)
8.What percent reduction occurs from vegetative cover?: 90-99%
9.What are soil properties?: Structure (particles
2/
8
Exam
1.Erosion Impact Area: area of land NOT ASSOCIATED with a current
land- disturbing activity but contributing to sedimentation
2.How much more soil loss occurs from construction sites versus natural
soil erosion rates? Agricultural land?: 1000 times more than the average
natural soil erosion rate.
20 times more than agricultural land.
3.What are 4 erosive forand ces?:
wind water
ice
gravit
y
4.Name and define 5 stages of soil erosion.: Raindrop- 90% of total soil
erosion Sheet- the soils ability to infiltrate water is exceeded and it runs
in sheet flow (about 100 ft before concentrating), how sediment gets
transported
1/
8
, Rill- when sheet flow begins to concentrate, velocity and turbulence
increase, but easily repaired
Gully-when rills converge, larger than rill and usually requires heavy
equipment to repair
Channel- large volume of water increases the gully, vertical sides are
observed or for an existing streambed when structural integrity is
destroyed
5.What are the factors of rainfall impact?: Kinetic energy is dependent on
rainfall amount/intensity, raindrop diameter, and raindrop velocity
6.What are two damaging effects of rainfall impact?: Causes soil
compression which reduces infiltration
Mainly occurs in May-Sept which is when disturbance is most active
7.4 factors influencing erosion:
climate groundcover (influenced by
humans)
soil properties
topography (influenced by humans)
8.What percent reduction occurs from vegetative cover?: 90-99%
9.What are soil properties?: Structure (particles
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8
