Questions and Answers
1.VESCP: Virginia Erosion and Sediment Control Program
- Administered by counties/cities (must), towns (may)
- MUST BE APPROVED
2.Minimum Standard 1: Stabilization
permanent or temporary soil stabilization shall be applied to denuded areas within seven
days after final grade is reached on any portion of the site; temporary soil stabilization shall
be applied within seven days to denuded areas that may not be at final grade but will remain
dormant for longer than 14 days; permanent stabilization shall be applied to areas that are to
be left dormant for more than one year
3.Site NOT at Final Grade: - stabilize in 14 days
- temporarily seed
- mulch
- permanently stabilize if dormant > 1 year
4.Site at Final Grade: - stabilize in 7 days (recommended immediately)
- permanently or temporarily seed and mulch
- mulch/matting/straw
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,5.Minimum Standard 2: Stock Piles, Waste and Borrow Areas
during construction, soil stock piles and borrow areas shall be stabilized or protected with
sediment trapping measures
mulch prevents erosion by protecting the surface from raindrop impact and silt fence
intercepts and detains from disturbed areas
6.Minimum Standard 3: Permanent Vegetation
permanent vegetation cover shall be established on denuded areas not otherwise
permanently stabilized (permanent vegetation shall not be considered established until a
ground cover is achieved that is uniform, mature enough to survive, and will inhibit
erosion *there is no % associated with this*)
reduce erosion and decrease sediment yield from disturbed area
this is the standard used to verify that a site is ready for release of bonds or surety
7.Minimum Standard 4: First-Step Measures
Sediment basins and traps, perimeter dikes, sediment barriers and other measures intended
to trap sediment shall be constructed as a first step in any land-disturbing
activity and shall be made functional before upslope land disturbance takes place
a certain amount of initial land disturbance may be required to provide access for equipment
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,to install the perimeter controls, but site clearing and grading should be kept to a minimum
until the perimeter controls are in place
intercepts and detains small amounts of sediment from disturbed areas during
construction operation to prevent sediment from leaving the site and decrease velocity
of sheet flows and low-to-moderate level channel flow
8.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
9.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
10.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
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, 11.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*
12.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.
13.Sediment Trapping Devises: 1. place near the lowest drainage points of a project
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