ESS 424 Exam 2 with Questions and
Correct Answers 2025
In lecture, we mentioned 5 ways of controlling hillslope detachment. List those. -
CORRECT ANSWERS Absorb raindrop impact
Absorb flow impact
Slow runoff velocity
Reduce runoff amounts
Increase soil's resistance to erosion
In lecture, we mentioned types of materials that absorb raindrop impact. List those. -
CORRECT ANSWERS Temporary vegetation, straw and mulches, rolled erosion control
products, hydro applications
If I protect the soil surface from flow turbulence impact, what effects does that generally
have on rill formation? - CORRECT ANSWERS Prevents it
What are the things that slowing the flow does to reduce hillslope detachment? -
CORRECT ANSWERS Less energy in turbulent eddies, gives runoff time to infiltrate,
spreads out flow further
What factors cause diminution of the soil roughness over time? - CORRECT ANSWERS
Rain drop impact, water erosion?
Under what condition might lots of vegetation not really slow down the flow? - CORRECT
ANSWERS If water does not flow through vegetation (must go through roughness)
Vegetation type, like trees don't slow flow
Describe "contour tillage" - CORRECT ANSWERS Creating channels that transport water
down slope without removing soil, tilling along lines of consistent elevation
Complete the following phrase: "If you concentrate the flow..." - CORRECT ANSWERS
You are responsible for it
What is the key to strong soil aggregates? - CORRECT ANSWERS Organic matter
In what ways do subsurface vegetative material (e.g. roots) help stop hillslope detachment
- CORRECT ANSWERS Functions as soil aggregate
, Besides protecting water quality, what are other goals of urban erosion and sediment
control? - CORRECT ANSWERS Protect aquatic wildlife, protect soil quality, prevent
transport and deposition elsewhere
What is the primary concern for urban erosion and sediment control generally limited to
while construction - CORRECT ANSWERS That sediment doesn't leave the site
Vegetation on construction sites should be removed no more than how many days before
earth-moving begins? - CORRECT ANSWERS Until building starts??
What are the benefits of compost compared to other mulches? - CORRECT ANSWERS
Heavier and nourishes the soil (C:N)
What is the critical element when using RECPs on construction sites? - CORRECT
ANSWERS Must touch the soil (prevent water from flowing underneath)
How do we usually stop sediment delivery from hillslopes? - CORRECT ANSWERS
RECPs? Diversions, terraces, grass waterways, slope drains
What are the two key elements for the use of permeable barriers? - CORRECT ANSWERS
Where runoff is expected in sheet flow, with slopes less than 300 ft in length (found for filter
berms)
Why is it important that buffer strips and spread the flow? - CORRECT ANSWERS
Mitigates the movement of sediment in agriculture?
How does a "graded terrace" get its collected water off the field? - CORRECT ANSWERS
Flows through grass waterways, graded channels, channels that hold till water infiltrates?
Why are specifically some of the problems with mining operations with respect to erosion
control? - CORRECT ANSWERS Acid mine drainage (AMD)
Acidic mine spoils materials and drainage result from exposure to water and air of rock
containing what? - CORRECT ANSWERS Sulfides (Ex: pyrite- Fe S)
Why the emphasis on roads in controlling forest erosion and sediment? - CORRECT
ANSWERS Forester roads are heavily used
Dirt roads become conduits for water flow, which follows path of least resistance
What are "water bars" in forest erosion and sediment control? - CORRECT ANSWERS
Packed bumps on road to divert water flow from road (prevent rills) Forces water to follow a
slope away from road
Why is stopping erosion so critical for landfills? - CORRECT ANSWERS Potentially toxic
runoff strangehills form exposing buried trash
Correct Answers 2025
In lecture, we mentioned 5 ways of controlling hillslope detachment. List those. -
CORRECT ANSWERS Absorb raindrop impact
Absorb flow impact
Slow runoff velocity
Reduce runoff amounts
Increase soil's resistance to erosion
In lecture, we mentioned types of materials that absorb raindrop impact. List those. -
CORRECT ANSWERS Temporary vegetation, straw and mulches, rolled erosion control
products, hydro applications
If I protect the soil surface from flow turbulence impact, what effects does that generally
have on rill formation? - CORRECT ANSWERS Prevents it
What are the things that slowing the flow does to reduce hillslope detachment? -
CORRECT ANSWERS Less energy in turbulent eddies, gives runoff time to infiltrate,
spreads out flow further
What factors cause diminution of the soil roughness over time? - CORRECT ANSWERS
Rain drop impact, water erosion?
Under what condition might lots of vegetation not really slow down the flow? - CORRECT
ANSWERS If water does not flow through vegetation (must go through roughness)
Vegetation type, like trees don't slow flow
Describe "contour tillage" - CORRECT ANSWERS Creating channels that transport water
down slope without removing soil, tilling along lines of consistent elevation
Complete the following phrase: "If you concentrate the flow..." - CORRECT ANSWERS
You are responsible for it
What is the key to strong soil aggregates? - CORRECT ANSWERS Organic matter
In what ways do subsurface vegetative material (e.g. roots) help stop hillslope detachment
- CORRECT ANSWERS Functions as soil aggregate
, Besides protecting water quality, what are other goals of urban erosion and sediment
control? - CORRECT ANSWERS Protect aquatic wildlife, protect soil quality, prevent
transport and deposition elsewhere
What is the primary concern for urban erosion and sediment control generally limited to
while construction - CORRECT ANSWERS That sediment doesn't leave the site
Vegetation on construction sites should be removed no more than how many days before
earth-moving begins? - CORRECT ANSWERS Until building starts??
What are the benefits of compost compared to other mulches? - CORRECT ANSWERS
Heavier and nourishes the soil (C:N)
What is the critical element when using RECPs on construction sites? - CORRECT
ANSWERS Must touch the soil (prevent water from flowing underneath)
How do we usually stop sediment delivery from hillslopes? - CORRECT ANSWERS
RECPs? Diversions, terraces, grass waterways, slope drains
What are the two key elements for the use of permeable barriers? - CORRECT ANSWERS
Where runoff is expected in sheet flow, with slopes less than 300 ft in length (found for filter
berms)
Why is it important that buffer strips and spread the flow? - CORRECT ANSWERS
Mitigates the movement of sediment in agriculture?
How does a "graded terrace" get its collected water off the field? - CORRECT ANSWERS
Flows through grass waterways, graded channels, channels that hold till water infiltrates?
Why are specifically some of the problems with mining operations with respect to erosion
control? - CORRECT ANSWERS Acid mine drainage (AMD)
Acidic mine spoils materials and drainage result from exposure to water and air of rock
containing what? - CORRECT ANSWERS Sulfides (Ex: pyrite- Fe S)
Why the emphasis on roads in controlling forest erosion and sediment? - CORRECT
ANSWERS Forester roads are heavily used
Dirt roads become conduits for water flow, which follows path of least resistance
What are "water bars" in forest erosion and sediment control? - CORRECT ANSWERS
Packed bumps on road to divert water flow from road (prevent rills) Forces water to follow a
slope away from road
Why is stopping erosion so critical for landfills? - CORRECT ANSWERS Potentially toxic
runoff strangehills form exposing buried trash
