C.M.R. 01, 001, ch. 565, ATTACHMENTS, att. C
Natural Resources Conservation Service
CONSERVATION PRACTICE STANDARD
WASTE STORAGE FACILITY
Code 313
(No)
November 2017
DEFINITION
An agricultural waste storage impoundment or containment made by constructing an embankment, excavating a pit or dugout, or by fabricating a structure.
Purpose
To store manure, agricultural by-products, wastewater, and contaminated runoff to provide the agricultural operation management flexibility for waste utilization.
Conditions Where Practice Applies
Use where regular 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 the NRCS Conservation Practice Standard (CPS) Waste Transfer (Code 634).
For liquid waste storage facilities implemented with an embankment, this practice applies only to low hazard structures as defined in the NRCS National Engineering Manual (NEM), Part 520.23.
This practice does not apply to the storage of human waste or routine animal mortality.
General Criteria Applicable to All Waste Storage Facilities.
Laws and Regulations. Plan, design, and construct the waste storage facility to meet all Federal, State, and local laws and regulations.
Location. Locate and design the waste storage facility such that it is outside the 100-year floodplain unless site restrictions require locating it within the floodplain. If located in the floodplain, protect the facility from inundation or damage from a 25-year flood event. Additionally, follow the policy found in the NRCS General Manual (GM) 190, Part 410.25, Floodplain Management, which may require providing additional protection for storage structures located within the floodplain.
Locate waste storage structures at least 100 feet from wells.
Waste storage facilities, other than field stacking facilities shall have a bottom elevation that is a minimum of 2 feet above the seasonal high water table. The storage shall have bottom elevation that is a minimum of 18 inches to bedrock. If the bedrock separation is less than 24 inches, then 6 inches of the separation profile must contain an impermeable layer. These separation distances and soils criteria are shown in Figure 1. The bottom elevation is defined as the lowest elevation manure is stored, for example, the top of the concrete floor.
Soils that do not meet the criteria in Figure 1 can be modified. Modifications to the site in order to meet seasonal high water table separation distance criteria shall address buoyant forces, pond seepage rate, and non-encroachment of the water table by contaminants. These modifications may include lowering the water table by the use of perimeter drains, building up the soil profile to increase the separation distance, or increasing setback distances from resource concerns. Any impermeable layers used to meet bedrock separation distance criteria shall use material such as clay. Material must be reviewed and approved by Soil Resource Specialist. If a site cannot be modified a synthetic liner may be used meeting the requirements found under Liners within Additional Criteria for Liquid Waste Storage
Consult with a Soil Resource Specialist to locate proposed waste storage facility and determine any modification needed to meet separation distances and soils criteria. Comply with all local, state, and federal laws and regulations on separation distances from resource concerns such as wells, property lines, water bodies, and aquifers.
Storage Period. The storage period is the maximum length of time anticipated between emptying events. Base the minimum storage period on the timing required for environmentally safe waste utilization considering the climate, crops, soil, equipment, and local, State, and Federal regulations.
Design Storage Volume. Size the facility to store the following volumes as appropriate.
Operational Volume
Manure, wastewater, bedding, and other wastes accumulated during the storage period. For liquid or slurry storage facilities, include normal precipitation (omit diverted roof runoff) less evaporation during the storage period. Normal runoff from the facility's drainage area during the storage period. Planned maximum residual solids. Provide a minimum of 6 inches for tanks unless a sump, ramp, or other device allows for complete emptying. Additional storage when required 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 at the maximum level of the required design storage. 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" for vertical walled tanks. Minimum of 12" for all other facilities.Exclude nonpolluted runoff from the structure to the fullest extent practical except where including the runoff is advantageous to the operation of the agricultural waste management system.
Inlet. Design inlet to resist corrosion, plugging, freeze damage, and ultraviolet deterioration. Incorporate erosion protection as necessary.
Waste Removal. Provide components for removing waste such as gates, pipes, docks, wet wells, pumping platforms, retaining walls, or ramps. Incorporate features to protect against erosion, tampering, and accidental release of stored waste as necessary. Design ramp slopes to accommodate anticipated equipment and traction available. Use NRCS CPS Nutrient Management (Code 590) for land application of stored material or follow other disposal options outlined in a Comprehensive Nutrient Management Plan (CNMP).
Accumulated Solids Removal. To preserve storage volume, make provision for periodic removal of accumulated solids. The anticipated method for solids removal must be accommodated in design, particularly in determining the configuration of impoundments and the type of liner to be used.
Maximum Operating Level. The maximum operating level for liquid storage structures is the level that provides the operational volume.
Staff Gauge. For earthen waste storage structures place 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). Emergency level (top of the design storage volume).For storages where the contents are not visible and a staff gauge would not be visible, such as below a slatted floor, identify the method for the operator to measure the depth of accumulated waste in the Operation and Maintenance Plan.
Safety. Include appropriate safety features to minimize the hazards of the facility (refer to American Society of Agricultural and Biological Engineers (ASABE) Standard EP470, Manure Storage Safety for guidance, as needed).
Provide warning signs, fences, ladders, ropes, bars, rails, and other devices as appropriate, to ensure the safety of humans and livestock. Provide ventilation and warning signs for covered waste holding structures, as necessary, to prevent explosion, poisoning, or asphyxiation.
Design covers and grating over openings such that livestock or humans cannot accidentally displace them and fall into the facility.
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.
Place a fence around impoundments and uncovered tanks which have exposed walls less than 5 feet above ground surface. Use the NRCS CPS Fence (Code 382) for design of a fence that will prevent accidental entry by people or animals likely to be onsite. Except at pushoff and unloading locations, fencing around waste storage facilities shall be one of the following:
Woven Wire, 6" grid, See typical drawing ME-FNC-WWF Chain Link, See typical drawing ME-FNC-CLFAt all pushoffs, pumping pads, and agitation locations, install safety features to prevent equipment, people, and livestock from accidentally falling into storage. Gate panels are to be used at pumping and agitation locations. Rail or bars are to be used at push-off locations. Position bar or rail so that the bucket or scarper can pass underneath.
Post universal warning signs, if needed, to prevent children and others from entering liquid waste storage structures.
Roofs and Covers. Use NRCS CPS Roofs and Covers (Code 367) for design of 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
A liquid waste storage impoundment is a 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, such as soil (although the unit may be lined with manmade materials) .
Liners. Select a liner material that will meet the requirements of the management, waste consistency, loading method, and unloading method. Use liners which meet or exceed NRCS CPS Pond Sealing or Lining (Codes: 520 - Compacted Soil Treatment, 521 - Geomembrane or Geosynthetic, or 522 -Concrete). Design concrete liners for reduced seepage. For concrete liners use 3500 psi concrete, 5" thick, with #4 rebar spaced 12" each direction. No cut joints are needed or allowed. Water stops are required at any cold joint.
Foundation. Locate the impoundment in soils with a permeability that meets all applicable regulations or line the impoundment with suitable material.
Perform subsurface investigations for all waste storage impoundments sufficient in detail and analysis to support the design in accordance with NRCS NEM, Part 531, Geology. Describe the soil material encountered, location of any seeps, depth-to-high-water table, depth to bedrock, and presence of sink holes in karst topography.
For the design of a liner on a site located in a floodplain and other locations where there is potential for uplift, include an evaluation of all potential buoyant uplift forces on the liner. 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.
Outlet. An outlet that can automatically release stored material is not permitted except for septic tanks that feed a treatment system such as a waste treatment strip 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 elevations.
Embankments. For an impoundment with greater than one acre of surface area and where wave action is a concern, increase the embankment height to account for calculated wave height. In all cases, increase the constructed embankment height by at least 5 percent to allow for settlement. Stabilize all embankments to prevent erosion or deterioration.
Minimum embankment top widths are shown in table 1. Design the combined side slopes of the settled embankment to be equal to or flatter than 5 horizontal to 1 vertical, with neither slope steeper than 2 horizontal to 1 vertical unless provisions are made for stability. The total embankment height (effective height) is the difference in elevation between the auxiliary (emergency) spillway crest or the settled top of the embankment if there is no auxiliary spillway and the lowest point in the cross section taken along the centerline of the embankment.
Table 1. Minimum Top Widths
Total embankment height (ft) | Top width (ft) |
Less than 15 | 8 |
15-19.9 | 10 |
20-24.9 | 12 |
25-30 | 14 |
30-35 | 15 |
Spillway or Equivalent Protection. For a facility having a total embankment height greater than 20 feet, construct an auxiliary (emergency) spillway or route through the spillway or store below the spillway another volume equivalent to the emergency volume.
Excavations. Design excavated side slopes to meet the requirements of the liner used, see NRCS CPS Pond Sealing or Lining, Compacted Soil Treatment (Code 520), Pond Sealing or Lining, Geomembrane or Geosynthetic (Code 521) or Pond Sealing or Lining, Concrete (Code 522).
Additional Criteria for Fabricated Structures
Definition. Fabricated structures include steel prefabricated tanks and waste storage structures constructed from precast or cast in place concrete walls with a concrete floor.
Foundation. Based on subsurface investigation, provide a foundation for fabricated waste storage structures to safely support all superimposed loads without excessive movement or settlement. Perform subsurface investigations for all fabricated structures sufficient in detail and analysis to support the design in accordance with NRCS NEM, Part 531, Geology. Describe the soil material encountered, location of any seeps, depth to high water table, depth to bedrock, and presence of sink holes in karst topography.
Where a nonuniform foundation cannot be avoided or where applied loads may create highly variable foundation loads, calculate settlement based upon site-specific soil test data. Index tests of site soil may allow correlation with similar soils for which test data is available. If no test data are available, use presumptive bearing strength values for assessing actual bearing pressures obtained from table 2 or another nationally recognized building code. In using presumptive bearing values, provide adequate detailing and articulation to avoid distressing movements in the structure.
Table 2. Presumptive Allowable Foundation and Lateral Pressure1
Class of materials | Allowable foundation pressure (psf) | Lateral bearing (psf/ft) below natural grade | Coefficient of friction | Cohesion (psf) |
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 |
1 International Building Code (IBC), 2015, International Code Council (ICC)
Structural Loadings. Design the waste storage structure to withstand all anticipated loads in accordance with the requirements in NRCS NEM, Part 536, Structural Design. Such loads should include 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. Table 3 provides minimum lateral earth pressure values when soil strength tests are not available. If heavy equipment will operate near the wall, use an additional soil surcharge or an additional internal lateral pressure in the wall analysis as appropriate.
For the lateral load from stored waste not protected from precipitation, use a minimum 65 lb/ft2/ft of depth as the design internal lateral pressure. Use a minimum value of 60 lb/ft2/ft of depth for the lateral load from 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
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 |
Clayey gravels, poorly graded gravel-sand mixes | GC | 45 | 60 |
Well-graded, clean sands; gravely sand mixes | SW | 30 | 60 |
Sand-silt clay mix with plastic fines | 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 | CL-ML | 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), 2015, International Code Council (ICC).
a Design loads based on moist conditions for the specified soils at optimum density. Include the weight of the buoyant soil plus hydrostatic pressure for submerged or saturated soil.
b Unsuitable as backfill material.
c Base the definition and classification of soil in accordance with ASTM D 2487.
Structural Design.Design structures with reinforced concrete, steel, wood, or masonry materials in accordance with NRCS-NEM, Part 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. Design structures according the latest versions of the following standards:
Loads: ASCE 7
Reinforced Concrete Structures:
Structural Members: ACI 318
Concrete Slabs for reduced seepage applications: ACI 360R
Concrete Slabs for non-water tight applications: ACI 330R
Steel Structures: AISC Steel construction Manual
Wood Structures: American Wood Council National Design Specifications for Wood Construction
Masonry Structures: ACI 530
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.
Sensitive Environmental Settings._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), design the storage structure as a reinforced concrete hydraulic or environmental structure according to NRCS NEM, Part 536, Structural Design. Alternatively, use a flexible liner membrane, designed and constructed in accordance with standard engineering and industry practice, to provide secondary liquid containment for structures constructed with other methods described in NRCS NEM, Part 536, Structural Design.
Additional Criteria - 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 the waste material. Construct a stacking facility of durable materials such as reinforced concrete, reinforced concrete block, or treated lumber. 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._Prevent leachate in amounts that would pollute surface or groundwater with collection and disposal of liquids in a safe manner as necessary. Seepage control may not be necessary on sites that have a roof. Make provisions for drainage of leachate, including rainfall from the stacking area (especially those without a roof). Collect leachate in a tank or waste storage impoundment, or properly treat in a vegetated treatment area.
Field Stacking Facilities Criteria
Design Criteria. Locate field stacking facilities to minimize the risk of surface and ground water contamination. Design considerations shall include the following:
ADDITIONAL CRITERIA FOR BEDDED PACKS
Sizing. Provide pack area for animals as listed in Table 4. If a heavy use area is used adjacent to the pack area and animals have free access to both areas, provide waste storage facility for manure collected on heavy use area. Size this waste storage facility to store up to 50 percent of the manure produced by the animals and 10 percent of the bedding used while they are using the pack and heavy use area.
Surface the pack area with concrete. Surround the pack area with reinforced concrete walls at least 6' tall.
Table 4:
Animal Type | Pack Area (sq ft/ animal) |
Dairy Cow | 85 - 100 |
Beef Cow | 85 - 100 |
Beef Steer | 75 - 85 |
Swine | 55 - 65 |
Sheep and Goats | 45 - 55 |
ADDITIONAL CRITERIA FOR CULL POTATO STORAGE
Acceptable surface treatments for cull potato storage facilities include an impervious soil barrier such as bituminous pavement or concrete. Handling and storage of cull potatoes shall be in accordance with the Maine Department of Agriculture Cull Potato Disposal Rules and Best Management Practices.
The storage volume occupied by the cull potatoes is based on the needed volume for the livestock being fed or the amount of potatoes stored. Sites can be relocated if resource concerns can be more economically addressed. All leachate concerns will be addressed according to practice standard Waste Treatment (629). NRCS conservation practice standards Waste Transfer (634), Heavy Use Area Protection (561), Subsurface Drain (606), Vegetated Treatment Area (635), Diversion (362), or any other pertinent practice standard that can be used as companion practices may also apply to the collection and treatment of cull potato leachate. Relocating the structure can be used where the high water table and bedrock separation distances cannot be met as specified in Figure 1. For proposes of designing leachate storage or treatment assume cull potatoes will produce 20 gallons of leachate per ton of cull potatoes stored.
CONSIDERATIONS
For exposed liners utilizing HDPE or similar materials that are slippery when wet, consider the use of textured liners or addition of features such as tire ladders that would allow for escape from the waste storage structure.
Consider 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.
Due consideration should be given to environmental concerns, economics, the overall waste management system plan, and safety and health factors.
Considerations for Siting
Consider the following factors in selecting a site for waste storage facilities:
Proximity of the waste storage facility to the source of waste. Access to other facilities. Ease of loading and unloading waste. Compatibility with the existing landforms and vegetation, including building arrangement, to minimize odors and adverse impacts on visual resources. Adequate maneuvering space for operating, loading, and unloading equipment.Considerations for Minimizing the Potential for and Impacts of Sudden Breach of Embankment or Accidental Release from the Waste Storage Facility.
Consider features, safeguards, and/or 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-
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 singly or in combination to minimize the potential of or the consequences of sudden breach of embankments:
An auxiliary (emergency) spillway. 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. Double liners.Options to consider to minimize the potential for accidental release from the waste storage facility through gravity outlets include-
Outlet gate locks or locked gate housing. Secondary containment. Alarm system. Another nongravity means of emptying the waste storage facility.Considerations for Minimizing the Potential of Waste Storage Pond Liner Failure.
Avoid sites with categories listed below unless no reasonable alternative exists.
Potential impact categories for liner failure are-
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.For a site with one or more of these site conditions, consider providing a leak detection system in conjunction with the planned liner to provide an additional measure of safety.
Considerations for Stacking Facilities
Internal seepage 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.
For any facility that is an organic producer or that sells manure to organic producers, consider using rot-resistant or treated lumber that meets the requirements for organic production. The producer should consult with the organic certifier as to the use and acceptability of treated lumber for waste storage.
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.
To reduce emissions of greenhouse gases, ammonia, volatile organic compounds, particulate matter and odor, other NRCS CPSs such as 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) can be added to the waste management system.
Adjusting pH below 7 may reduce ammonia emissions from the waste storage facility but may increase odor when waste is surface applied-see NRCS CPS Nutrient Management (Code 590).
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 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. Structural details of all components, including reinforcing steel, type of materials, thickness, anchorage requirements, lift thickness. Locations, sizes, and type of pipelines and appurtenances. Requirements for foundation and preparation and treatment. Vegetative requirements. Quantities. Approximate location of utilities and notification 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 where appropriate:
Include the operational requirements for emptying the storage facility including the expected storage period. Begin removal of the liquid storage facility as soon as practical after the maximum operating level has been reached. Also include the requirement that waste be removed from storage and utilized at locations, times, rates, and volume in accordance with the overall waste management system plan.
For impoundments and other liquid storages include an explanation of the staff gauge or other permanent marker to indicate the maximum operating level. For storages where the contents are not visible and a staff gauge would not be visible, such as below a slatted floor, identify the method for the operator to measure the depth of accumulated waste.
Include a provision 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.
Include instructions as needed for ventilating confined spaces according to ASABE Standard S607, Venting 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.
Include a description of the routine maintenance needed for each component of the facility. Also include provisions for maintenance that may be needed as a result of waste removal or material deterioration.
REFERENCES
American Society for Testing and Materials. Annual Book of ASTM Standards. Standards D 653, D 698, D 1760, D 2488. ASTM, Philadelphia, PA.
USDA NRCS. 1992. Agricultural Waste Management Field Handbook. USDA-NRCS, Washington, DC.
USDA NRCS. General Manual. USDA-NRCS, Washington, DC.
USDA NRCS. National Engineering Manual. USDA-NRCS, Washington, DC.
USDA Soil Conservation Service. 1989. Technical Release Number 74, Lateral Earth Pressures, USDA-SCS, Washington, DC.
References for NRCS Code 313
These Codes reference the following publications:
-- National Handbook of Conservation Practices. 2015. USDANRCS
-- Fencing USDA NRCS Maine Code 382. 08/14.
-- Vegetated Treatment Areas USDA NRCS MaineCode 393. 02/17
-- Agricultural Waste Management Field Handbook, Chapter 7. USDA NRCS. 4/92.
-- American Society of Agricultural Engineers. EP288.5, Agricultural Building Snow and Wind Loads. 2001.
C.M.R. 01, 001, ch. 565, ATTACHMENTS, att. C