Spoil Spreading

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                                CONSERVATION PRACTICE STANDARD

                                            SPOIL SPREADING

                                                       CODE 572

DEFINITION                                                         species appropriate to the soil, climate
                                                                   conditions and land use. Refer to NRCS
Disposal of surplus excavated materials.                           Conservation Practice Standard 342, Critical
                                                                   Area Planting for criteria on vegetative
PURPOSE                                                            establishment.
To dispose of excess soil from construction                        If spoil spreading is completed at a time of year
activities in an environmentally sound manner                      that is not conducive to the establishment of
that minimizes soil erosion, protects water                        the desired plant species, utilize temporary
quality and fits with the land use and                             erosion control measures immediately and
landscape.                                                         maintain the measures until the site can be
                                                                   successfully vegetated.

CONDITIONS WHERE PRACTICE APPLIES                                  Before placing spoil material that has physical
                                                                   or chemical characteristics that prevent the
This practice applies to sites where spoil                         establishment of adequate vegetation, strip
material is available from the excavation of                       topsoil from the spoil area. Use the topsoil or
open channels, ponds or other construction                         other suitable soil material to cover the spoil
sites.                                                             with a minimum of 6 inches of soil prior to
CRITERIA                                                           Spoils that are known or suspected to be
Plan and design spoil spreading to comply with                     contaminated with toxic substances must be
all federal, state, and local laws and                             tested to determine the nature and toxicity of
regulations.                                                       the contamination. This is particularly true of
                                                                   waterborne sediments that drain from industrial
Locate spoil spreading areas as close as                           or urban areas. Based upon the evaluation
practical to the excavation area to minimize                       develop a plan to remove and dispose of the
haul distance. Spread spoil in relatively                          spoil in an environmentally sound manner.
uniform layers, maintaining positive drainage
away from the spoil. Do not spread spoil when                      Additional Criteria for Spoil Spreading
the ground or spoil is frozen or excessively wet                   Along Channels, Canals and Streambanks.
unless site specific design considerations
                                                                   Choose the location and placement of spoil to
indicate frozen or wet conditions will not have
                                                                   avoid the destruction of vegetation in Riparian
adverse effects.
                                                                   Zones 1 and 2 as defined in NRCS
Design spoil areas to blend with the landscape                     Conservation Practice Standard 391, Riparian
and planned land use. Use slopes that are                          Forest Buffer and 390, Riparian Herbaceous
stable and fit the land use. For areas that will                   Cover.
be cropped or mowed use slopes of 4
                                                                   Design the placement of spoil so that it does
horizontal to 1 (4:1) vertical or flatter.
                                                                   not endanger the stability of the channel.
Establish vegetation on spoil areas                                Place the spoil so that it will not immediately
immediately after spreading unless the area                        fall or erode back into the channel.
will be cropped within 30 days. Use plant

Conservation practice standards are reviewed periodically and updated if needed. To obtain         NRCS, NHCP
the current version of this standard, contact your Natural Resources Conservation Service
State Office or visit the Field Office Technical Guide.                                           January 2010
572 - 2

If the spoil is used to establish a berm along a     applying the practice according to this
channel, design slopes on the channel side not       standard. Plans and specifications for this
steeper than 3 horizontal to 1 vertical (3:1). On    practice may be incorporated into the plans
the land side, design slopes not steeper than 4      and specification for the practice it serves. As a
horizontal to 1 vertical (4:1). Heights of berms     minimum the plans and specifications shall
shall not exceed 3 feet above the original           include:
                                                        A plan view showing the location of the
Check the channel capacity with the spoil in             spoil area.
place to ensure that channel capacity will not
adversely affect upstream drainage.                     Lift thickness for spoil placement.

Design the placement of spoil to provide for the        Maximum and/or minimum slopes for spoil
safe passage of surface water that collects on           areas.
the land side of the spoil into the channel.            Typical cross sections of spoil areas.
Where necessary, use pipes, channels or
structures to convey runoff into the channel.           Maximum and or minimum height of
Refer to NRCS Conservation Practice                      spread spoil above existing ground
Standard 410, Grade Stabilization Structure for          surface.
criteria for structure design.
                                                        An estimate of quantities.
Where a travel way is needed to facilitate
                                                        Construction specifications that describe in
maintenance along the bank of a channel,
                                                         writing the site specific installation
place and shape the spoil to provide access for
                                                         requirements for the spoil spreading.
maintenance or other activities. Refer to NRCS
Conservation Practice Standard 560, Access
Road for criteria for the construction of a travel   OPERATION AND MAINTENANCE
way along the spoil.
                                                     Prepare an operation and maintenance (O&M)
                                                     plan for the operator. The minimum
CONSIDERATIONS                                       requirements to be addressed in a written O&M
                                                     plan are:
Spoil areas need not be waste areas. Spoil
areas should blend with the landscape and the           Inspection of the spoil areas within six
land use. Plan the location, slopes and                  months after spreading and periodically
vegetation to benefit the planned land use.              thereafter.
Landscape quality can be improved by the                Fill or repair any excessive rills or gullies in
creative placement of spoil material. Spoil              the spoil.
material can be used to block undesirable
views, deflect or redirect agricultural runoff,         Reestablish vegetation as necessary on
wind or snow, or block noise.                            the repaired areas.
Spoil areas with permanent vegetation can               Mow the vegetation as necessary to
provide excellent wildlife habitat. When                 maintain a dense, vigorous stand.
choosing vegetation for these areas select
                                                        Control undesirable species and/or noxious
native species that will provide food and cover
                                                         weeds as necessary.
for wildlife.
The construction of berms along one or both
sides of a channel can affect channel capacity,      USDA Natural Resources Conservation
and out of bank flow. When planning the              Service. 2008. Engineering Field Handbook,
location of spoil areas consider how the spoil       Chapter 17 Construction and Construction
placement will affect the flow regime of the         Materials, National Engineering Handbook,
channel.                                             650.17.

Prepare plans and specifications for spoil
spreading that describe the requirements for
January 2010