EROSION AND SEDIMENT CONTROL QUESTIONS AND ANSWERS

EROSION AND SEDIMENT CONTROL
QUESTIONS AND ANSWERS
Minimum Standard 1 - ans-Stabilization sq sq sq sq




permanent or temporary soil stabilization shall be applied to denuded areas within seven d
sq sq sq sq sq sq sq sq sq sq sq sq sq




ays after final grade is reached on any portion of the site; temporary soil stabilization shall b
sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq




e applied within seven days to denuded areas that may not be at final grade but will remain
sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq




dormant for longer than 14 days; permanent stabilization shall be applied to areas that are t
sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq




o be left dormant for more than one year
sq sq sq sq sq sq sq sq




Site NOT at Final Grade - ans-- stabilize in 14 days
sq sq sq sq sq sq sq sq sq sq




- temporarily seed
sq sq




- mulch
sq




- permanently stabilize if dormant > 1 year
sq sq sq sq sq sq sq




Site at Final Grade - ans-- stabilize in 7 days (recommended immediately)
sq sq sq sq sq sq sq sq sq sq sq




- permanently or temporarily seed and mulch
sq sq sq sq sq sq




- mulch/matting/straw
sq




Minimum Standard 2 - ans-Stock Piles, Waste and Borrow Areas sq sq sq sq sq sq sq sq sq




during construction, soil stock piles and borrow areas shall be stabilized or protected with s
sq sq sq sq sq sq sq sq sq sq sq sq sq sq




ediment trapping measures sq sq




mulch prevents erosion by protecting the surface from raindrop impact and silt fence interc
sq sq sq sq sq sq sq sq sq sq sq sq sq




epts and detains from disturbed areas
sq sq sq sq sq




Minimum Standard 3 - ans-Permanent Vegetation sq sq sq sq sq




permanent vegetation cover shall be established on denuded areas not otherwise perman
sq sq sq sq sq sq sq sq sq sq sq




ently stabilized (permanent vegetation shall not be considered established until a ground c
sq sq sq sq sq sq sq sq sq sq sq sq




over is achieved that is uniform, mature enough to survive, and will inhibit erosion *there is
sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq




no % associated with this*)
sq sq sq sq sq




reduce erosion and decrease sediment yield from disturbed area
sq sq sq sq sq sq sq sq




this is the standard used to verify that a site is ready for release of bonds or surety
sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq

,Minimum Standard 4 - ans-First-Step Measures sq sq sq sq sq




Sediment basins and traps, perimeter dikes, sediment barriers and other measures intend
sq sq sq sq sq sq sq sq sq sq sq




ed to trap sediment shall be constructed as a first step in any land-
sq sq sq sq sq sq sq sq sq sq sq sq sq




disturbing activity and shall be made functional before upslope land disturbance takes plac
sq sq sq sq sq sq sq sq sq sq sq sq




e

a certain amount of initial land disturbance may be required to provide access for equipmen
sq sq sq sq sq sq sq sq sq sq sq sq sq sq




t to install the perimeter controls, but site clearing and grading should be kept to a minimum
sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq




until the perimeter controls are in place
sq sq sq sq sq sq




intercepts and detains small amounts of sediment from disturbed areas during constructio
sq sq sq sq sq sq sq sq sq sq sq




n operation to prevent sediment from leaving the site and decrease velocity of sheet flows a
sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq




nd low-to-moderate level channel flow
sq sq sq sq




Perimeter Controls - ans-assures that sediment does not leave the perimeter of the land-
sq sq sq sq sq sq sq sq sq sq sq sq sq




disturbing area once site clearing, grading, and construction commences
sq sq sq sq sq sq sq sq




Examples: silt fences, sediment traps, sediment basins, construction entrance, temporary
sq sq sq sq sq sq sq sq sq sq




diversions, diversions sq




Minimum Standard 5 - ans-Earthen Structure Stabilization sq sq sq sq sq sq




stabilization measures shall be applied to earthen structures such as dams, dikes, and dive
sq sq sq sq sq sq sq sq sq sq sq sq sq




rsions immediately after installationsq sq sq




reduce erosion and sedimentation and reduce damage from sediment and runoff to downst
sq sq sq sq sq sq sq sq sq sq sq sq




ream or off-site areas sq sq sq




Minimum Standard 6 - ans-Traps and Basins sq sq sq sq sq sq




sediment traps and basins shall be designed and constructed based upon the total drainag
sq sq sq sq sq sq sq sq sq sq sq sq sq




e area (not just disturbed area) to be served by the trap or basin
sq sq sq sq sq sq sq sq sq sq sq sq sq




Sediment Traps - ans- sq sq sq




minimum storage capacity shall be 134 cubic yards per acre of drainage area and shall only
sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq




control drainage areas less than 3 acres
sq sq sq sq sq sq sq




*stone outlet = trap* sq sq sq




Sediment Basins - ans- sq sq sq




surface runoff from disturbed areas that is comprised of flow from drainage areas greater th
sq sq sq sq sq sq sq sq sq sq sq sq sq sq




an or equal to 3 acres shall be controlled by a basin; minimum storage capacity of a sedime
sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq




nt basin shall be 134 cubic yards per acre of drainage area; the outfall system shall, at a min
sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq




imum, maintain the structural integrity of the basin during a 25-year storm of 24-
sq sq sq sq sq sq sq sq sq sq sq sq sq

, hour duration; runoff coefficients used in runoff calculations shall correspond to a bare eart
sq sq sq sq sq sq sq sq sq sq sq sq sq




h condition or those conditions expected to exist while the sediment basin is utilized.
sq sq sq sq sq sq sq sq sq sq sq sq sq




Sediment Trapping Devises - ans-1. place near the lowest drainage points of a project
sq sq sq sq sq sq sq sq sq sq sq sq sq




2. install as a first-step measure [MS-4]
sq sq sq sq sq sq




3. stabilize immediately [MS-5]
sq sq sq




4. must include outlet protection for basins [MS-11]
sq sq sq sq sq sq sq




Minimum Standard 7 - ans-Cut and Fill Slopes sq sq sq sq sq sq sq




roughening the surface of the slope decreases runoff, lowers the velocity runoff, increases
sq sq sq sq sq sq sq sq sq sq sq sq sq




water retention, and leads to better seed germination
sq sq sq sq sq sq sq




slopes that are found to be eroding excessively within on year of permanent stabilization sh
sq sq sq sq sq sq sq sq sq sq sq sq sq sq




all be provided with additional slop stabilizing measures until the problem is corrected
sq sq sq sq sq sq sq sq sq sq sq sq




Minimum Standard 8 - ans-Concentrated Runoff sq sq sq sq sq




shall not flow down cut or fill slopes unless contained within an adequate temporary or per
sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq




manent channel, flume or slope drain structure
sq sq sq sq sq sq




outlets of these drains need outlet protection to prevent erosion from the concentrated flow
sq sq sq sq sq sq sq sq sq sq sq sq sq




size of pipe depends on drainage area
sq sq sq sq sq sq




temporarily conduct concentrated stormwater runoff safely down the face of a cut or fill slop
sq sq sq sq sq sq sq sq sq sq sq sq sq sq




e without causing erosion on or below the slope
sq sq sq sq sq sq sq sq




Minimum Standard 9 - ans-Water Seeps sq sq sq sq sq




whenever water seeps from a slope face, adequate drainage or other protection shall be pr
sq sq sq sq sq sq sq sq sq sq sq sq sq sq




ovided

cut and fill operations may expose shallow aquifers or groundwater tables from which wate
sq sq sq sq sq sq sq sq sq sq sq sq sq




r may seep through the side of a slope
sq sq sq sq sq sq sq sq




Minimum Standard 10 - ans-Inlet Protection sq sq sq sq sq




all storm sewer inlets that are made operable during construction shall be protected so that
sq sq sq sq sq sq sq sq sq sq sq sq sq sq sq




sediment-
laden water cannot enter the conveyance system without first being filtered or otherwise tre
sq sq sq sq sq sq sq sq sq sq sq sq sq




ated to remove sediment
sq sq sq