United States Department of Agriculture 313-CPS-1

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NRCS reviews and periodically updates conservation practice standards. To obtain the current 

version of this standard, contact your Natural Resources Conservation Service State office or 

visit the Field Office Technical Guide online by going to the NRCS website at 

https://www.nrcs.usda.gov/ and type FOTG in the search field. 

USDA is an equal opportunity provider, employer, and lender.

Natural Resources Conservation Service 

CONSERVATION PRACTICE STANDARD 

WASTE STORAGE FACILITY 

CODE 313 

(no)

DEFINITION 

An agricultural waste storage impoundment or containment structure. 

PURPOSE 

This practice is used to accomplish one or more of the following purposes– 

• Minimize or eliminate the impacts on surface water. 

• Minimize or eliminate the impacts on groundwater resources. 

• Minimize emissions such as greenhouse gases to improve air quality. 

CONDITIONS WHERE PRACTICE APPLIES 

Use where storage is needed for wastes generated by agricultural production or processing and where

soils, geology, and topography are suitable for construction of the facility. For reception pits, use NRCS

Conservation Practice Standard (CPS) Waste Transfer (Code 634). 

For liquid waste storage facilities with an embankment, this practice applies only to low hazard structures.

A low hazard structure is defined as a dam in a rural or agricultural area where failure may damage farm

building, agricultural land, or township and country roads (Title 210, National Engineering Manual (NEM),

Part 520, Section 520.21,”Definition and Classes”). 

This practice does not apply to the storage of human waste or to a facility used exclusively for routine

animal mortality. Use NRCS CPS Animal Mortality Facility (Code 316), for routine animal mortality. 

CRITERIA 

General Criteria Applicable to All Purposes 

Laws and Regulations 

Plan, design, and construct the waste storage facility to meet all Federal, Tribal, State and local laws and

regulations. 

Location 

Locate the waste storage facility outside the 100-year floodplain, unless site restrictions require locating it

within the floodplain. Protect the facility from inundation from a 25-year flood event and structural damage

from the 100-year flood event, if located within the floodplain. Additionally, follow the policy found in Title

190 General Manual, Ecological Sciences, Part 410, Subpart B, Section 410.25 Flood Plain Management,

which may require additional protection, planning, or operating measures. 

Foundation 

Perform surface and subsurface investigations for all waste storage facilities sufficient in detail and

analysis to support the design in accordance with Title 210, National Engineering Manual, Part -531,
“Geology” (210-NEM-531). Document the soil material encountered, the location of any seeps, the depth

to water table, the depth to bedrock, the presence of sink holes, karst topography, the description and

location to nearest water well(s), and other conditions that might affect the suitability of the site. Additional

foundation criteria are listed specific to Criteria for Liquid Waste Storage Impoundments and Additional

Criteria for Fabricated Structures. 

Storage Period 

The storage period is the maximum length of time anticipated between emptying events. Base the storage

period on the timing required for environmentally safe utilization considering climate, crops, soils, and

equipment. 

Design Storage Volume 

Size the facility to store the following volumes: 

Operational Volume 

• Manure, wastewater, bedding, and other wastes accumulated during the storage period. 

• Include normal monthly precipitation less evaporation, where appropriate, during the storage period

for liquid or slurry storage facilities. 

• Normal runoff from the facility’s drainage area during the storage period. 

• Planned maximum residual solids. Provide a minimum of 6 inches for residual solids in tanks unless

provisions that allow for complete emptying are included. 

• Additional storage to meet management goals or regulatory requirements. 

Emergency Volume (liquid storages only) 

• 25-year, 24-hour precipitation on the surface of the liquid or slurry storage facility. 

• 25-year, 24-hour runoff from the facility’s drainage area. 

Freeboard Volume (for liquid or slurry waste storage exposed to precipitation) 

• Minimum of 6 inches for vertical walled facilities. 

• Minimum of 12 inches for all other facilities and under-floor storages that require pit ventilation. 

Freeboard is not required for roofed facilities that do not receive runoff unless required for ventilation. 

Exclude non-polluted runoff from the structure where practical except where inclusion is advantageous to

the operation of the facility. 

Inlet Structures 

Design inlet to resist corrosion, plugging, freeze damage, and ultraviolet deterioration. Design must

incorporate erosion protection. For inlet structures, use NRCS CPS Waste Transfer (Code 634). 

Waste Removal Components 

Design components for removing waste such as gates, pipes, docks, wet wells, pumping platforms,

retaining walls, or ramps in accordance with the applicable CPS, including but not limited to NRCS CPS

Heavy Use Area (Code 561), Pumping Plant (Code 533) or Waste Transfer (Code 634). Account for all

items that will influence the performance of the component including loading, durability, serviceability,

material properties, and construction quality. Incorporate features to protect against erosion, tampering,

and accidental release of stored waste. Design ramp slopes to accommodate anticipated equipment and

traction. Components must be compatible with the land application methods specified in the nutrient

management plan, NRCS CPS Nutrient Management (Code 590). 

Accumulated Solids Removal 

Preserve storage volume by including a provision for periodic removal of accumulated solids. Design the

facility to accommodate the anticipated method of removing accumulated solids. This is important for

determining the configuration of impoundments and the liner to be used. 

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Maximum Operating Level 

The maximum operating level for liquid storage structures is the level that provides the operational

volume. 

Staff Gauge 

Locate and specify the requirements for a staff gauge or other permanent marker in the liquid storage

facility to clearly indicate the following elevations: 

• Maximum operating level (top of the operational volume). 

• Top of emergency volume. 

Identify the method for the operator to measure the depth of accumulated waste in the Operation and

Maintenance Plan, for facilities where the contents are not visible and a staff gauge would not be visible,

such as below a slatted floor. 

Safety 

Include appropriate safety features to minimize the hazards of the facility (refer to American Society of

Agricultural Engineers (ASAE) Standard EP470, Manure Storage Safety for guidance, as needed). 

Provide appropriate warning signs, ladders, ropes bars, rails, and other safety devices. Include type,

number, location, and details for installation of required safety features. 

Use warning signs to identify the potential for explosion, poisoning, or asphyxiation. 

Design covers and gratings over openings such that livestock or humans cannot accidentally displace

them and fall into the facility. Design covers and gratings to handle expected operation loads. 

Design pipelines with a water-sealed trap and vent, or similar device, if there is a potential for gases from

the pipe to accumulate in confined spaces. 

A fence is required around impoundments, excavated ponds, and uncovered tanks which have exposed

walls less than 5 feet above the ground surface. Use NRCS CPS Fence (Code 382) to design a fence that

will prevent accidental entry by people or animals. Post universal warning signs to prevent entry into liquid

waste storage structures. 

Roofs and Covers 

Use NRCS CPS Roofs and Covers (Code 367) to design waste storage facility covers or roofs, as

needed. 

Treated Wood 

Use criteria from NRCS CPS Roof and Covers (Code 367) for treated wood and fasteners. 

Additional Criteria for Liquid Waste Storage Impoundments 

A liquid waste storage impoundment is a waste storage facility where the stored material does not

consistently stack and is either a natural topographic depression, manmade excavation, or diked area

formed primarily of earthen materials (although the facility may be lined with manmade materials). 

Foundation 

Locate the impoundment in soils with a permeability that meets all applicable regulations or line the

impoundment with suitable material. Use liners which meet or exceed NRCS CPS Pond Sealing or Lining,

Compacted Soil Treatment (Code 520), Pond Sealing or Lining, Geomembrane or Geosynthetic Clay

Liner (Code 521), or Pond Sealing or Lining, Concrete ( Code 522). Install an engineered pond liner or

ensure foundation materials meet the maximum specific discharge rate as recommended by NRCS in

AWMFH Appendix 10D or meets State or local regulations, whichever is more restrictive. 

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Include an evaluation in the liner design of all buoyant uplift forces on the liner for sites located in a

floodplain or where there is potential for uplift. Limit projected uplift head under clay liners to a gradient of

less than 0.5 ft/ft in the clay liner. The gradient is determined as the difference in total head between the

top and the bottom of a clay liner when buoyant forces exist (such as when the floodplain is flooded)

divided by the thickness of the clay liner. 

Design Bottom Elevation 

Locate the bottom elevation a minimum of 2 feet above the seasonal high-water table, to protect the

integrity of the liner, unless special design features are incorporated that address buoyant forces,

impoundment seepage rate and non-encroachment of the water table by contaminants. The water table

may be lowered by use of drains to meet this requirement. 

Outlet 

Do not use an outlet that can automatically release stored material except for septic tanks that feed a

treatment system such as a vegetated treatement area or leaching field, or outlets leading to another

storage facility with adequate capacity. Design a permanent outlet that will resist corrosion and plugging.

Provide a backflow prevention measure for an outlet that pumps wastewater to secondary storage located

at a higher elevation. This section does not apply to an auxiliary spillway. 

Embankments 

Design embankments to withstand loads associated with the waste storage structure. Increase

embankment height by a minimum of 5% to allow for settling. Stabilize all embankments to prevent

erosion or deterioration. Raise the embankment height where wave action may be a concern and protect

the slope from wave action. 

• Top width: Design minimum embankment top widths according to table 1. 

• Side slopes: Design the combined side slopes of the settled embankment no steeper than 5-to-1.

Design both side slopes no steeper than a 2-to-1 ratio, unless provisions are made for stability. 

• Effective height: The difference between the bottom of the spillway crest (or the settled top of the

embankment if there is no auxiliary spillway) and the lowest point on the existing ground along the

embankment. 

• Total embankment height is the difference between the settled top of the embankment and the

lowest point on the existing ground along the embankment. 

Table 1. Minimum Top Widths 

 

When effective height exceeds 20 feet, provide embankment protection by: 

• Including an auxiliary spillway with the capacity to route the 25-year, 24-hour storm runoff from the

facility drainage plus the 25-year, 24-hour precipitation volume on the surface of the liquid or slurry

storage facility or a minimum of two feet of elevation difference between the crest of the auxiliary

spillway and the top of the settled embankment, whichever is greater. 

• For embankments without an auxiliiary spillway raise the embankment above the design storage

Total embankment 

height (ft)

Top width, (ft)

Less than 15 8

15–19.9 10

20–24.9 12

25–34.9 14

35 or more 15 

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volume an additional 25-year, 24-hour storm runoff from the facility drainage plus the 25-year, 24-

hour precipitation volume on the surface of the liquid or slurry storage facility or one foot of

freeboard whichever is greater. 

Excavations 

Specify excavated side slopes to meet the requirements of the type of liner selected, see NRCS CPS

Pond Sealing or Lining, Compacted Soil Treatment (Code 520), Pond Sealing or Lining, Geomembrane or

Geosynthetic Clay Liner (Code 521) or Pond Sealing or Lining, Concrete (Code 522). 

Additional Criteria for Fabricated Structures 

Foundation 

Provide a foundation for fabricated waste storage structures to safely support all superimposed loads

without excessive movement or settlement, based on the subsurface investigation (210-NEM-531). 

Calculate settlement based upon site-specific soil test data, where a nonuniform foundation cannot be

avoided or where applied loads may create highly variable foundation loads. Index tests of site soil may

allow correlation with similar soils for which test data is available. Use presumptive bearing strength

values for assessing actual bearing pressures obtained from table 2 or another nationally recognized

building code when site-specific soil test data is not available. Provide adequate detailing and articulation

to avoid distressing movements in the structure when using presumptive bearing values. 

 

Table 2. Presumptive Allowable Foundation and Lateral Pressure1 

Class of

Materials

Vertical

Foundati

on

Pressure

(psf)

Lateral Bearing Pressure 

(psf/ft below natural

grade)

Coefficient of Frictiona Cohesion (psf)b

Crystalline

bedrock 12,000 1,200 0.70 -

Sedimentary

and foliated

rock

4,000 400 0.35 -

Sandy gravel

or gravel

(GW and GP)

3,000 200 0.35 -

Sand, silty

sand, clayey

sand, silty

gravel, clayey

gravel (SW,

SP, SM, SC,

GM and GC)

2,000 150 0.25 -

Clay, sandy

clay, silty

clay, clayey

silt, silt and

sandy silt

(CL, ML, MH

and CH)

1,500 100 - 130

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For bedrock foundations, separate the floor slab and the bedrock by: 

• A minimum of 2 feet of soil or, 

• A liner that meets or exceeds NRCS CPS Pond Sealing or Lining, Compacted Soil Treatment (Code

520), Pond Sealing or Lining, Geomembrane or Geosynthetic Clay Liner (Code 521), or Pond

Sealing or Lining, Concrete (Code 522) or, 

• Other appropriate method or alternative that achieves equal protection. 

Structural Loadings 

Design the waste storage structure to withstand all anticipated loads in accordance with the requirements

in Title 210, National Engineering Manual, Part 536, “Structural Design” (210-NEM-536), including, as

applicable, internal and external loads, hydrostatic uplift pressure, concentrated surface and impact loads,

and water pressure due to seasonal high-water table, frost or ice. 

Calculate loading from lateral earth pressures using soil strength values determined from the results of

appropriate soil tests and procedures described in Technical Release 210-74, “Lateral Earth Pressures”.

ASCE or ACI criteria may be used where appropriate. Table 3 provides minimum lateral earth pressure

values when soil strength tests are not available. Use an additional soil surcharge or an additional internal

lateral pressure in the wall analysis when equipment will operate near the wall. 

Use a minimum internal lateral pressure of 65 lb/ft2/ft of depth for stored waste that is not protected from

precipitation. Use a minimum internal lateral pressure of 60 lb/ft2/ft of depth for stored waste protected

from precipitation and not likely to become saturated. Use a minimum internal lateral pressure of 72 lb/ft2/ft

of depth for sand-laden manure storage if the percentage of sand exceeds 20%. Designers may use

lesser values if supported by measurement of actual pressures of the waste to be stored. 

Table 3. Minimum Lateral Earth Pressure Values1 

Class of

Materials

Vertical

Foundati

on

Pressure

(psf)

Lateral Bearing Pressure 

(psf/ft below natural

grade)

Coefficient of Frictiona Cohesion (psf)b

1 International Building Code (IBC), 2018, International Code Council (ICC) 

a Coefficient to be multiplied by the dead load. 

b Cohesion value to be multiplied by the contact area, as limited by Section 1806.3.2 Lateral sliding

resistance limit. For clay, sandy clay, silty clay, clayey silt, silt and sandy silt, the lateral sliding resistance

shall not exceed one-half the dead load.

Description of Backfill

Material c

Unified Soil

Classification

Design Lateral Soil Load (lb/ft2/ft of depth) a

Active pressure At-rest pressure

Well-graded, clean

gravels; gravel-sand

mixes GW 30 60

Poorly graded clean

gravels; gravel-sand

mixes GP 30 60

Silty gravels, poorly

graded gravel-sand

mixes GM 40 60

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Structural Design 

Design structures with reinforced concrete, steel, wood, or masonry materials in accordance with 210-

NEM-536, Structural Engineering. Account for all items that will influence the performance of the structure,

including loading assumptions, durability, serviceability, material properties and construction quality.

Ensure that the material used for a fabricated structure is compatible with the waste product to be stored. 

Tanks may be designed with or without a cover. Design openings in a covered tank to accommodate

equipment for loading, agitating, and emptying. Equip these openings with fencing, grills or secure covers

for safety, and for odor and vector control as necessary. 

Description of Backfill

Material c

Unified Soil

Classification

Design Lateral Soil Load (lb/ft2/ft of depth) a

Active pressure At-rest pressure

Clayey gravels, poorly

graded gravel-sand

mixes GC 45 60

Well-graded, clean

sands; gravely sand

mixes SW 30 60

Poorly graded clean

sands; sand-gravel

mixes SP 30 60

Silty sands,poorly

graded sand-silt mixes SM 45 60

Sand-silt clay mix with

plastic fines SM-SC 45 100

Clayey sands, poorly

graded sand-clay mixes SC 60 100

Inorganic silts and

clayey silts ML 45 100

Mixture of inorganic silt

and clay ML-CL 60 100

Inorganic clays of low to

medium plasticity CL 60 100

Organic silts and silt

clays, low plasticity OL Note b Note b

Inorganic clayey silts,

elastic silts MH Note b Note b

Inorganic clays of high

plasticity CH Note b Note b

Organic clays and silty

clays OH Note b Note b

1 Table 1610.1, Lateral Soil Load, International Building Code (IBC), 2018, International Code Council

(ICC). 

a Design loads based on moist conditions for the specified soils at optimum density. Actual field

conditions shall govern. Submerged or saturated soil presures shall include the weight of the buoyant

soil plus hydrostatic loads. 

b Unsuitable as backfill material. 

c The definition and classification of soil materials shall be in accordance with ASTM D2487.

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Sensitive Environmental Settings 

Classify and design the storage structure as a reinforced concrete hydraulic or environmental structure

according to 210-NEM-536 where liquid-storage is to be provided in sensitive environmental settings (i.e.,

tanks in areas with shallow wells in surface aquifers, high-risk karst topography, or other site-specific

concerns). Alternatively, use a flexible liner membrane, designed in accordance with standard engineering

and industry practice, to provide secondary liquid containment for structures constructed with other

methods described in 210-NEM-536. 

Additional Criteria for Stacking Facilities 

A stacking facility may be open, covered, or roofed and is used for wastes which behave primarily as solid.

Determine the wall height using the anticipated stacking angle of repose of the waste material and any

clearance height needed for containment of the stacked material. Construct a stacking facility of durable

materials. Design the stacking facility with adequate safety factors to prevent failure due to internal or

external pressures, including hydrostatic uplift pressure and imposed surface loads such as equipment

which may be used within, on, or adjacent to the structure. 

Seepage and Internal Drainage 

Locate the stacking facility in soils with a permeability that meets all applicable regulations and use the

appropriate NRCS CPS Pond Sealing or Lining, Compacted Soil Treatment (Code 520), Geomembrane or

Geosynthetic Clay Liner (Code 521), or Concrete (Code 522) to reduce the potential for groundwater

contamination. 

Collect and utilize leachate in a safe manner to prevent pollution of surface or groundwater. Prevent

influent seepage or surface runoff from infringing on the designed storage capacity or on the suitability of

the waste being stacked and stored. Leachate control may not be needed on sites that have a roof, waste

material with little seepage potential, or are located in arid climates. 

Make provisions for drainage of leachate, including rainfall from the stacking area (especially those

without a roof). Collect leachate and transfer to a tank, waste storage impoundment, treatment lagoon, or

vegetated treatment area. 

Poultry Litter Stacking Facility 

For wood walled facilities, design the height of the litter stack not to exceed 7 feet, with litter to wood

contact limited to 5 feet to reduce the potential for spontaneous combustion damage. 

CONSIDERATIONS 

General Considerations 

Consider the use of textured liners or addition of features such as tire ladders, that would allow for escape

from the waste storage structures, for exposed liners utilizing HDPE or similar materials that are slippery

when wet. 

Solid/liquid separation of runoff or wastewater entering impoundments to minimize the frequency of

accumulated solids removal and to facilitate pumping and application of the stored waste. 

Consider environmental concerns, economics, the overall waste management system plan, and safety

and health factors. 

Provide the operator with the cost to close the facility since the economics and risks associated with waste

storage facilities are quite high. Cost should include removal of the planned sludge accumulation volume

and the waste stored at the maximum operating volume. 

Considerations for Siting 

Consider the following factors in selecting a site: 

• Proximity to the source of waste. 

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• Access to other facilities. 

• Ease of loading and unloading waste. 

• Compatibility with the existing landforms, vegetation, and prevailing winds, including building

arrangement to minimize odors and adverse impacts on visual resources. 

• Adequate maneuvering space for operating, loading, and unloading equipment. 

• Distance to surface water, wells, non-farm residence(s), and property lines. 

• Avoid locating waste storage facilities upwind of areas where heavy gasses may accumulate. 

Considerations for Minimizing Impacts of Sudden Breach of Embankment or Accidental Release

from the Waste Storage 

Consider features, safeguards, and management measures to minimize the risk of failure or accidental

release, or to minimize or mitigate impact of this type of failure when any of the categories listed below

might be significantly affected. 

Potential impact categories from breach of embankment or accidental release include: 

• Downstream drinking water sources. 

• Surface water bodies—perennial streams, lakes, wetlands, and estuaries. 

• Critical habitat for threatened and endangered species. 

• Riparian areas. 

• Farmstead, or other areas of habitation. 

• Off-farm property. 

• Historical and archaeological sites or structures that meet the eligibility criteria for listing in the

National Register of Historical Places. 

Consider the following either individually or in combination to minimize the potential of or the

consequences of sudden breach of embankments: 

• An auxiliary spillway. 

• Additional emergency volume. 

• Additional freeboard. 

• Storage for wet year rather than normal year precipitation. 

• Reinforced embankment— such as, additional top width, flattened and/or armored downstream side

slopes. 

• Secondary containment. 

• Dual liner. 

Consider the following options to minimize the potential for accidental release from the waste storage

facility through gravity outlets. 

Comment on noting that electronic monitoring of water levels is available. 

• Outlet gate locks or locked gate housing. 

• Secondary containment. 

• Addition of an electronic water elevation monitoring device or alarm system. 

• Another non-gravity means of emptying the waste storage facility. 

Considerations for Minimizing the Potential of Storage Pond Liner Failure 

Avoid sites with categories listed below unless no reasonable alternative exists. 

Potential impact categories for liner failure are: 

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• Any underlying aquifer is at a shallow depth and not confined. 

• The vadose zone is rock. 

• The aquifer is a domestic water supply or ecologically vital water supply. 

• The site is located in an area of water-soluble bedrock such as limestone or gypsum. 

Consider providing a leak detection system in conjunction with the planned liner to provide an additional

measure of safety for a site with one or more of these site conditions. 

Considerations for Stacking Facilities 

Leachate collection within a stacking facility can be accomplished by use of a timber wall with the boards

installed vertically, leaving 3/4-inch cracks. The timber wall drainage section may be included in a concrete

or masonry block wall. Use the design criteria for timber walls. 

Considerations for Organic Operations 

Use rot-resistant or treated lumber that meets the requirements for organic production for any facility that

is an organic producer or that sells manure to organic producers. The producer should consult with the

organic certifier as to the use and acceptability of treated lumber for waste storage. 

Considerations for Health and Safety 

Consider the following options to minimize health and safety issues: 

• Include adequate ventilation, especially when agitating stored manure. 

• Add emergency equipment such as multi-gas monitor, buoys and self-contained breathing

apparatus. 

• Remove potential sources of sparks. 

• Impacts of low berms around manure storage structures that can trap heavy gases and allow gases

to collect above manure storages. 

Considerations for Improving Air Quality 

Liquid manure storage may result in emissions of volatile organic compounds, ammonia, hydrogen sulfide,

methane, nitrous oxide, and carbon dioxide. Solid manure storage may result in emissions of particulate

matter, volatile organic compounds, ammonia, carbon dioxide, and nitrous oxide. Consider minimizing

liquid storage time to reduce emissions. 

Reduce emissions of greenhouse gases, ammonia, volatile organic compounds, particulate matter and

odor, by adding other NRCS CPSs Anaerobic Digester (Code 366), Roofs and Covers (Code 367), Waste

Treatment (Code 629), Amendments for Treatment of Agricultural Waste (Code 591), Composting Facility

(Code 317), and Air Filtration and Scrubbing (Code 371) to the waste management system. 

Some fabric and organic covers have been shown to be effective in reducing odors. 

Maintain appropriate manure moisture content for solid manure storage facilities. Excessive moisture will

increase the potential for air emissions of volatile organic compounds, ammonia, and nitrous oxide, and

may lead to anaerobic conditions, which will increase the potential for emissions of methane and

hydrogen sulfide. Too little moisture will increase the potential for dust and other particulate matter

emissions. 

PLANS AND SPECIFICATIONS 

Prepare plans and specifications that describe the requirements for applying the practice to achieve its

intended use. As a minimum, include the following in the engineering plans and specifications: 

• Plan view of system layout with relevant benchmark elevation and descriptions. 

• Structural details of all components, including reinforcing steel, type of materials, and thickness. 

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• Locations, sizes, and type of pipelines and appurtenances. 

• Requirements for foundation preparation and treatment. 

• Backfill requirements: lift thickness, method of compaction, material type, material size and

moisture content. 

• Safety features. 

• Material quantities. 

• Approximate location of utilities and notification requirements. 

• Vegetative requirements. 

 

OPERATION AND MAINTENANCE 

Develop an operation and maintenance plan that is consistent with the purposes of the practice, its

intended life, safety requirements, and the criteria for its design. At a minimum, the plan will contain the

following information where appropriate: 

• Operational requirements for emptying the storage facility and the expected storage period. Begin

removal of the liquid storage facility as soon as practical before the maximum operating level has

been reached. Include the requirement that waste be removed from storage and utilized at

locations, times, rates, and volume in accordance with NRCS CPS Nutrient Management (Code

590). 

• Explanation of the staff gauge or other permanent marker to indicate the maximum operating level,

for impoundments and other liquid storages. Identify the method for the operator to measure the

depth of accumulated waste, for storages where the contents are not visible and a staff gauge

would not be visible, such as below a slatted floor. 

• Provisions for emergency removal and disposition of liquid waste in the event of an unusual storm

event that may cause the waste storage structure to fill to capacity prematurely. 

• Instructions, as needed, for ventilating confined spaces according to ASABE standard S607,

Ventilating Manure Storages to Reduce Entry Risk. 

• Develop an emergency action plan for waste storage facilities where there is a potential for

significant impact from breach or accidental release. Include site-specific provisions for emergency

actions that will minimize these impacts. 

• Describe the routine maintenance needed for each component of the facility. Include provisions for

maintenance that may be needed as a result of waste removal or material deterioration. 

REFERENCES 

American Society of Agricultural and Biological Engineers. 2010. Ventilating Manure Storages to Reduce

Entry Risk. ANSI/ASAES607. OCT (R2019). ASABE, St. Joseph, MI. 

American Society of Agricultural Engineers. 2011. Manure Storage Safety. ANSI/ASAE EP470.1 OCT

(R2016). ASAE, St. Joseph, MI. 

ASTM Standard D653. 2020. Standard Terminology Relating to Soil, Rock, and Contained Fluids. ASTM

International, West Conshohocken, PA. 

ASTM Standard D698. 2021. Standard Test Methods for Laboratory Compaction Characteristics of Soil

Using Standard Effort (12,400 ft-lbf/ft3 (600 kN-m/m3)). ASTM International, West Conshohocken, PA. 

ASTM Standard D2487. 2017. Standard Practice for Classification of Soils for Engineering Purposes

(Unified Soil Classification System). ASTM International, West Conshohocken, PA. 

International Code Council (ICC), International Building Code (IBC), 2018. 

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USDA Natural Resources Conservation Service (NRCS). 2013. Agricultural Waste Management Field

Handbook. USDA-NRCS, Washington, DC. 

USDA NRCS. Title 190, General Manual, Part 410.25 Flood Pain Management. Washington, DC. 

USDA NRCS. 2017. Title 210, National Engineering Manual (NEM), Part 520, Section 520.21, Definition

and Classes. Washington, D.C. 

USDA NRCS. 2017. Title 210, NEM, Part 536, Structural Engineering. Washington, D.C. 

USDA NRCS. 2019. Title 210, NEM, Part 531, Geology. Washington, D.C. 

USDA Office of the Chief Economist. 2014. Technical Bulletin 1939, Quantifying Greenhouse Gas Fluxes

in Agriculture and Forestry: Methods for Entity-Scale Inventory, Washington, DC., July.. 

USDA Soil Conservation Service. 1989. Technical Release Number 74, Lateral Earth Pressures, USDASCS, Washington, DC.

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