VA DEQ SWM INSPECTOR CORRECT FINALS
QUESTIONS AND ANSWERS SURE A+
✔✔Perimeter Controls - ✔✔assures that sediment does not leave the perimeter of the
land-disturbing area once site clearing, grading, and construction commences
Examples: silt fences, sediment traps, sediment basins, construction entrance,
temporary diversions, diversions
✔✔Minimum Standard 5 - ✔✔Earthen Structure Stabilization
stabilization measures shall be applied to earthen structures such as dams, dikes, and
diversions immediately after installation
reduce erosion and sedimentation and reduce damage from sediment and runoff to
downstream or off-site areas
✔✔Minimum Standard 6 - ✔✔Traps and Basins
sediment traps and basins shall be designed and constructed based upon the total
drainage area (not just disturbed area) to be served by the trap or basin
✔✔Sediment Traps - ✔✔minimum storage capacity shall be 134 cubic yards per acre of
drainage area and shall only control drainage areas less than 3 acres
*stone outlet = trap*
✔✔Sediment Basins - ✔✔surface runoff from disturbed areas that is comprised of flow
from drainage areas greater than or equal to 3 acres shall be controlled by a basin;
minimum storage capacity of a sediment basin shall be 134 cubic yards per acre of
drainage area; the outfall system shall, at a minimum, maintain the structural integrity of
the basin during a 25-year storm of 24-hour duration; runoff coefficients used in runoff
,calculations shall correspond to a bare earth condition or those conditions expected to
exist while the sediment basin is utilized.
✔✔Sediment Trapping Devises - ✔✔1. place near the lowest drainage points of a
project
2. install as a first-step measure [MS-4]
3. stabilize immediately [MS-5]
4. must include outlet protection for basins [MS-11]
✔✔Minimum Standard 7 - ✔✔Cut and Fill Slopes
roughening the surface of the slope decreases runoff, lowers the velocity runoff,
increases water retention, and leads to better seed germination
slopes that are found to be eroding excessively within on year of permanent stabilization
shall be provided with additional slop stabilizing measures until the problem is corrected
✔✔Minimum Standard 8 - ✔✔Concentrated Runoff
shall not flow down cut or fill slopes unless contained within an adequate temporary or
permanent channel, flume or slope drain structure
outlets of these drains need outlet protection to prevent erosion from the concentrated
flow
size of pipe depends on drainage area
temporarily conduct concentrated stormwater runoff safely down the face of a cut or fill
slope without causing erosion on or below the slope
✔✔Minimum Standard 9 - ✔✔Water Seeps
whenever water seeps from a slope face, adequate drainage or other protection shall be
provided
cut and fill operations may expose shallow aquifers or groundwater tables from which
water may seep through the side of a slope
✔✔Minimum Standard 10 - ✔✔Inlet Protection
all storm sewer inlets that are made operable during construction shall be protected so
that sediment-laden water cannot enter the conveyance system without first being
filtered or otherwise treated to remove sediment
, storm sewers are designed to efficiently transport stormwater away from the site, so
when sediment enters the storm sewer system, two negative effects can occur:
1. when velocity of flow is high, much of the sediment will be quickly transported to the
nearest receiving channel
2. when velocity of the flow is low, the sediment may be deposited in the pipes resulting
in clogging and potential flooding of a site during storm events
prevents sediment from entering storm drainage systems prior to permanent
stabilization of the disturbed area
✔✔Silt Fence Drop Inlet Protection vs. Block and Gravel Drop Inlet Sediment Filter -
✔✔Block and gravel drop inlet - will have to clean out regularly but won't get damaged.
✔✔Minimum Standard 11 - ✔✔Outlet Protection
before newly constructed stormwater conveyance channels or pipes are made
operational, adequate outlet protection and any required temporary or permanent
channel lining shall be installed in both the conveyance channel and receiving channel
prevent scour at stormwater outlets, protect outlet structure, and minimize potential for
downstream erosion by reducing the velocity and energy of concentrated stormwater
flows
provides energy dissipation from the concentrated discharge from a pipe or channel in
order to prevent erosion and provide a stable transition
must construct at zero grade (so it slows down water to slow/prevent erosion)
✔✔Minimum Standard 12 - ✔✔Watercourse Construction
when work in a live watercourse is performed, precautions shall be taken to minimize
encroachment, control sediment transport, and stabilize the work area to the greatest
extent possible during construction
non-erodible material shall be used from the construction of causeways and cofferdams
earthen fill may be used for these structures if armored by non-erodible cover materials
use of non-erodible materials prevents damage to the stream bed and sedimentation
✔✔Minimum Standard 13 - ✔✔when a live watercourse must be crossed by
construction vehicles more than twice in any six-month period, a temporary vehicular
stream crossing constructed of non-erodible material shall be provided
QUESTIONS AND ANSWERS SURE A+
✔✔Perimeter Controls - ✔✔assures that sediment does not leave the perimeter of the
land-disturbing area once site clearing, grading, and construction commences
Examples: silt fences, sediment traps, sediment basins, construction entrance,
temporary diversions, diversions
✔✔Minimum Standard 5 - ✔✔Earthen Structure Stabilization
stabilization measures shall be applied to earthen structures such as dams, dikes, and
diversions immediately after installation
reduce erosion and sedimentation and reduce damage from sediment and runoff to
downstream or off-site areas
✔✔Minimum Standard 6 - ✔✔Traps and Basins
sediment traps and basins shall be designed and constructed based upon the total
drainage area (not just disturbed area) to be served by the trap or basin
✔✔Sediment Traps - ✔✔minimum storage capacity shall be 134 cubic yards per acre of
drainage area and shall only control drainage areas less than 3 acres
*stone outlet = trap*
✔✔Sediment Basins - ✔✔surface runoff from disturbed areas that is comprised of flow
from drainage areas greater than or equal to 3 acres shall be controlled by a basin;
minimum storage capacity of a sediment basin shall be 134 cubic yards per acre of
drainage area; the outfall system shall, at a minimum, maintain the structural integrity of
the basin during a 25-year storm of 24-hour duration; runoff coefficients used in runoff
,calculations shall correspond to a bare earth condition or those conditions expected to
exist while the sediment basin is utilized.
✔✔Sediment Trapping Devises - ✔✔1. place near the lowest drainage points of a
project
2. install as a first-step measure [MS-4]
3. stabilize immediately [MS-5]
4. must include outlet protection for basins [MS-11]
✔✔Minimum Standard 7 - ✔✔Cut and Fill Slopes
roughening the surface of the slope decreases runoff, lowers the velocity runoff,
increases water retention, and leads to better seed germination
slopes that are found to be eroding excessively within on year of permanent stabilization
shall be provided with additional slop stabilizing measures until the problem is corrected
✔✔Minimum Standard 8 - ✔✔Concentrated Runoff
shall not flow down cut or fill slopes unless contained within an adequate temporary or
permanent channel, flume or slope drain structure
outlets of these drains need outlet protection to prevent erosion from the concentrated
flow
size of pipe depends on drainage area
temporarily conduct concentrated stormwater runoff safely down the face of a cut or fill
slope without causing erosion on or below the slope
✔✔Minimum Standard 9 - ✔✔Water Seeps
whenever water seeps from a slope face, adequate drainage or other protection shall be
provided
cut and fill operations may expose shallow aquifers or groundwater tables from which
water may seep through the side of a slope
✔✔Minimum Standard 10 - ✔✔Inlet Protection
all storm sewer inlets that are made operable during construction shall be protected so
that sediment-laden water cannot enter the conveyance system without first being
filtered or otherwise treated to remove sediment
, storm sewers are designed to efficiently transport stormwater away from the site, so
when sediment enters the storm sewer system, two negative effects can occur:
1. when velocity of flow is high, much of the sediment will be quickly transported to the
nearest receiving channel
2. when velocity of the flow is low, the sediment may be deposited in the pipes resulting
in clogging and potential flooding of a site during storm events
prevents sediment from entering storm drainage systems prior to permanent
stabilization of the disturbed area
✔✔Silt Fence Drop Inlet Protection vs. Block and Gravel Drop Inlet Sediment Filter -
✔✔Block and gravel drop inlet - will have to clean out regularly but won't get damaged.
✔✔Minimum Standard 11 - ✔✔Outlet Protection
before newly constructed stormwater conveyance channels or pipes are made
operational, adequate outlet protection and any required temporary or permanent
channel lining shall be installed in both the conveyance channel and receiving channel
prevent scour at stormwater outlets, protect outlet structure, and minimize potential for
downstream erosion by reducing the velocity and energy of concentrated stormwater
flows
provides energy dissipation from the concentrated discharge from a pipe or channel in
order to prevent erosion and provide a stable transition
must construct at zero grade (so it slows down water to slow/prevent erosion)
✔✔Minimum Standard 12 - ✔✔Watercourse Construction
when work in a live watercourse is performed, precautions shall be taken to minimize
encroachment, control sediment transport, and stabilize the work area to the greatest
extent possible during construction
non-erodible material shall be used from the construction of causeways and cofferdams
earthen fill may be used for these structures if armored by non-erodible cover materials
use of non-erodible materials prevents damage to the stream bed and sedimentation
✔✔Minimum Standard 13 - ✔✔when a live watercourse must be crossed by
construction vehicles more than twice in any six-month period, a temporary vehicular
stream crossing constructed of non-erodible material shall be provided
