NPDES CLASS: NATIONAL POLLUTANT
DISCHARGE ELIMINATION SYSTEM,
2025/2026 WITH CORRECT/ACCURATE
ANSWERS
NATIONAL POLLUTANT DISCHARGE
ELIMINATION SYSTEM
Erosion - CORRECT-ANSWERS--is the process by which the land surface is
worn away by the action of wind, water, and gravity. >>> The primary
agents that cause erosion are water, wind, ice (glaciers), and gravity.
Erosion is a fundamental geological process that shapes landscapes over
time, creating valleys, canyons, and coastlines.
Sedimentation - CORRECT-ANSWERS--is the settling out of soil particles
transported by water and wind.
Soil erosion can be classified as 2 types. What are they? - CORRECT-
ANSWERS--Wind and Water.
What are the two sources of Soil erosion. - CORRECT-ANSWERS--Natural
and Manmade >>> Water Erosion
,Water is the leading cause of soil erosion globally due to its abundance
and power to dislodge and transport soil particles. This can occur in
several forms:
Raindrop Impact (Splash Erosion): The initial impact of raindrops
physically detaches soil particles.
Surface Runoff (Sheet/Rill/Gully Erosion): When rain or snowmelt flows
over the land surface, it carries detached particles with it. This can form
small channels (rills) that can grow into large, deep trenches (gullies).
Stream/Riverbank Erosion: The continuous flow of water in channels wears
away the banks and bed of the watercourse.
2. Wind Erosion
Wind erosion is particularly severe in dry, arid, and semi-arid regions with
sparse vegetation cover. Strong winds lift and transport loose soil particles
over varying distances:
Saltation: Soil particles bounce along the surface.
Suspension: Very fine particles are lifted high into the air and carried over
long distances (e.g., dust storms).
Surface Creep: Larger, heavier particles are rolled or slid along the ground
surface by the force of the wind or impacts from saltating particles.
Water erosion can be classified as two type of erosions. What are they? -
CORRECT-ANSWERS--Overland and Stream/Channel erosion.
Four process of overland erosion are? - CORRECT-ANSWERS--Splash,
sheet, rill, and gully erosion.
Four principle factors influencing soil erosion are? - CORRECT-ANSWERS--
Soil characteristics, vegetative cover, topography, and climate.
, List three physical effect of erosion and sedimentation: - CORRECT-
ANSWERS--Increased flooding reduced hydraulic capacity in rivers, and
streams; increased maintenance of stormwater systems.; increased water
treatments cost; and decreased recreational value.
List three biological effect of erosion and sedimentation: - CORRECT-
ANSWERS--Reduced light for aquatic plants; clogs fish gills; impairs
spawning; disrupts food chain; blankets bottom, suppresses aquatic life;
and disrupts ecosystem.
Planning the development to fit the terrain using the particular: -
CORRECT-ANSWERS--Topography; soils; drainage patterns; natural
vegetation of the site; and minimize the extent of the area exposed at one
time and the duration of exposure.
Perimeter Control Practices - CORRECT-ANSWERS--What you apply to
protect the disturbed area from off-site runoff and to protect off-site areas
from sediment damage.
Erosion Control Practices - CORRECT-ANSWERS--What you apply to
prevent excessive on-site damage.
Keep runoff velocities _____ and _______ runoff on the site - CORRECT-
ANSWERS--Low and retain
DISCHARGE ELIMINATION SYSTEM,
2025/2026 WITH CORRECT/ACCURATE
ANSWERS
NATIONAL POLLUTANT DISCHARGE
ELIMINATION SYSTEM
Erosion - CORRECT-ANSWERS--is the process by which the land surface is
worn away by the action of wind, water, and gravity. >>> The primary
agents that cause erosion are water, wind, ice (glaciers), and gravity.
Erosion is a fundamental geological process that shapes landscapes over
time, creating valleys, canyons, and coastlines.
Sedimentation - CORRECT-ANSWERS--is the settling out of soil particles
transported by water and wind.
Soil erosion can be classified as 2 types. What are they? - CORRECT-
ANSWERS--Wind and Water.
What are the two sources of Soil erosion. - CORRECT-ANSWERS--Natural
and Manmade >>> Water Erosion
,Water is the leading cause of soil erosion globally due to its abundance
and power to dislodge and transport soil particles. This can occur in
several forms:
Raindrop Impact (Splash Erosion): The initial impact of raindrops
physically detaches soil particles.
Surface Runoff (Sheet/Rill/Gully Erosion): When rain or snowmelt flows
over the land surface, it carries detached particles with it. This can form
small channels (rills) that can grow into large, deep trenches (gullies).
Stream/Riverbank Erosion: The continuous flow of water in channels wears
away the banks and bed of the watercourse.
2. Wind Erosion
Wind erosion is particularly severe in dry, arid, and semi-arid regions with
sparse vegetation cover. Strong winds lift and transport loose soil particles
over varying distances:
Saltation: Soil particles bounce along the surface.
Suspension: Very fine particles are lifted high into the air and carried over
long distances (e.g., dust storms).
Surface Creep: Larger, heavier particles are rolled or slid along the ground
surface by the force of the wind or impacts from saltating particles.
Water erosion can be classified as two type of erosions. What are they? -
CORRECT-ANSWERS--Overland and Stream/Channel erosion.
Four process of overland erosion are? - CORRECT-ANSWERS--Splash,
sheet, rill, and gully erosion.
Four principle factors influencing soil erosion are? - CORRECT-ANSWERS--
Soil characteristics, vegetative cover, topography, and climate.
, List three physical effect of erosion and sedimentation: - CORRECT-
ANSWERS--Increased flooding reduced hydraulic capacity in rivers, and
streams; increased maintenance of stormwater systems.; increased water
treatments cost; and decreased recreational value.
List three biological effect of erosion and sedimentation: - CORRECT-
ANSWERS--Reduced light for aquatic plants; clogs fish gills; impairs
spawning; disrupts food chain; blankets bottom, suppresses aquatic life;
and disrupts ecosystem.
Planning the development to fit the terrain using the particular: -
CORRECT-ANSWERS--Topography; soils; drainage patterns; natural
vegetation of the site; and minimize the extent of the area exposed at one
time and the duration of exposure.
Perimeter Control Practices - CORRECT-ANSWERS--What you apply to
protect the disturbed area from off-site runoff and to protect off-site areas
from sediment damage.
Erosion Control Practices - CORRECT-ANSWERS--What you apply to
prevent excessive on-site damage.
Keep runoff velocities _____ and _______ runoff on the site - CORRECT-
ANSWERS--Low and retain
