10 CSR 20-8.300
Design of Concentrated Animal Feeding Operations
PURPOSE: This rule specifies the minimum standards for the design of animal waste management systems. It does not address all
aspects of design, and the design engineer may refer to other appropriate reference materials so long as these minimum standards
set forth in this rule are met.
PUBLISHER’S NOTE: The secretary of state has determined that the
publication of the entire text of the material which is incorporated
by reference as a portion of this rule would be unduly cumbersome
or expensive. This material as incorporated by reference in this
rule shall be maintained by the agency at its headquarters and
shall be made available to the public for inspection and copying
at no more than the actual cost of reproduction. This note applies
only to the reference material. The entire text of the rule is printed
here.
(1) Applicability. This rule applies to all new or expanding
Concentrated Animal Feeding Operations (CAFOs), however,
only those applicants that are constructing earthen basins
are required to obtain construction permits. The Missouri
Department of Natural Resources (department) will not examine the adequacy or efficiency of the structural, mechanical,
or electrical components of the concentrated animal feeding
operation systems, only adherence to rules and regulations.
(2) Definitions.
(A) Definitions as set forth in the Missouri Clean Water Law,
Chapter 644, Concentrated Animal Feeding Operation (Hog
Bill) section 640.703, RSMo, 10 CSR 20-2.010, and 10 CSR 20-6.300
shall apply to the terms in this rule unless otherwise defined by
subsection (2)(B) below.
(B) Other applicable definitions are as follows:
1. Design storage period—The calculated number of days
that will fill the manure storage structure from the lower to the
upper operating level for a covered storage structure or from
the lower to the upper operating level for an uncovered, liquid
storage structure during a period of average rainfall minus
evaporation (R-E).
A. For a design storage period of fewer than three
hundred sixty-five (365) days, the largest consecutive average
monthly R-E, corresponding with the number of months of the
storage period, shall be used.
B. For multiple storage stages, the storage period is the
sum of available storage days in each stage.
C. For covered liquid manure storage structures, the
upper operating level is one foot (1') below the top of the structure;
2. Freeboard—The elevation difference between the bottom of the spillway to the top of the berm for an earthen basin;
3. Groundwater table—The seasonal high water level
occurring beneath the surface of the ground, including underground watercourses, artesian basins, underground reservoirs
and lakes, aquifers, other bodies of water located below the
surface of the ground, and water in the saturated zone. For the
purposes of this rule, groundwater table does not include the
perched water table;
4. Manure—The fecal and urinary excretion of animals;
5. Manure storage structure—A fabricated structure or
earthen basin used to store manure, litter, and/or process
wastewater;
6. Rainfall minus evaporation (R-E)— The average depth of
monthly liquid precipitation minus evaporation as published
in the most recent National Weather Service Climate Atlas for
the geographical region of the proposed structure;
7. Safety depth—One foot (1') of liquid depth or the depth
needed to hold the volume of the ten- (10-) year, ten- (10-) day
storm, whichever is greater;
8. Solid manure—Manure that can be stacked without free
flowing liquids;
9. Safety volume—The volume of wastewater stored between the upper pumpdown and emergency spillway crest;
10. Storage lagoon—A lagoon that does not have adequate
volume to accomplish treatment;
11. Storage volume—The volume of manure, runoff, washwater, rainfall, and additional water sources between the lower
and upper operating levels;
12. Ten- (10-) year, ten- (10-) day storm—The depth of rainfall occurring in a ten- (10-) day duration over a ten- (10-) year
return frequency as defined by the most recent publication of
the National Weather Service Climate Atlas for the geographical region of the proposed manure storage structure;
13. Total storage capacity—The combined volume of storage and safety volumes stored between the lower pumpdown
level and emergency spillway crest;
14. Treatment volume—The permanent volume maintained below the lower pumpdown designed for anaerobic
treatment of manure based on latitude;
15. Waste treatment lagoon—A lagoon that is sized to have
three hundred sixty-five (365) days of storage volume and adequate treatment volume;
16. Wastewater—A combination of manure, washwater,
runoff, rainfall, and process wastewater; and
17. Wastewater flow—The annual rate of wastewater contributed to an animal waste management system.
(3) Permit Application Documents. All engineering documents
shall be prepared by, or under the direct supervision of, a registered professional engineer licensed to practice in Missouri.
(4) Location.
(A) Protection from Flooding—Manure storage structures,
confinement buildings, open lots, composting pads, and other
manure storage areas in the production area shall be protected
from inundation or damage due to the one hundred- (100-)
year flood.
(B) The minimum setback distances from manure storage
structures, manure storage areas, confinement buildings, open
lots, or mortality composters shall be as follows:
1. Ten feet (10') to public water supply pipelines;
2. Fifty feet (50') to property lines;
3. Fifty feet (50') to public roads;
4. One hundred feet (100') to wetlands, ponds, or lakes not
used for human water supply;
5. One hundred feet (100') to gaining streams (classified or
unclassified; perennial or intermittent);
6. Three hundred feet (300') to human water supply lakes
or impoundments; and
7. Three hundred feet (300') to losing streams (classified or
unclassified; perennial or intermittent) and sinkholes.
(C) Distances from earthen basins shall be measured from the
outside edge of the top of the berm.
(5) Manure Storage Structure Sizing.
(A) No Discharge Requirement. All manure storage structures
shall comply with the design standards and effluent limitations
of 10 CSR 20-6.300(4).
(B) Design Storage Period. The minimum design storage period for manure storage structures shall be as follows:
1. The minimum design storage period for liquid manure,
solid manure, and dry process waste to be land applied is one
hundred eighty (180) days;
2. The minimum design storage period for solid manure
and dry process waste to be sold or used as bedding is ninety
(90) days; and
3. The minimum design storage period for waste treatment lagoons without an impermeable cover is three hundred
sixty-five (365) days.
(C) New Class I swine, veal, or poultry operations shall
evaluate proposed uncovered manure storage structures in
accordance with applicable federal regulation as set forth in
40 CFR 412.46(a)(1), November 20, 2008, and shall hereby be
incorporated by reference, without any later amendments or
additions, as published by the Office of the Federal Register,
National Archives and Records Administration, Superintendent
of Documents, Pittsburgh, PA 15250-7954.
(D) Sizing Manure Storage Structures.
1. The structure shall be designed to hold all inputs,
between the upper and lower operating levels, anticipated
during the design storage period.
2. Uncovered liquid storage structures shall also include:
A. One-in-ten (1-in-10) year rainfall minus evaporation
from the surface of the structure, held between the operating
levels; and
B. Safety volume based on the twenty-five (25) year,
twenty-four (24) hour storm event above the upper operating
level.
3. Tanks and pits shall also include six inches (6") of depth
below the lower operating level for incomplete removal allowance.
4. Earthen basins shall also include:
A. At least one foot (1') of freeboard or two feet (2') for
structures that receive storm water from open lots larger than
the surface area of the storage structure;
B. Two feet (2') of permanent liquid depth below the
lower operating level. Anaerobic treatment volume greater
than two feet (2') will satisfy this requirement;
C. Sludge accumulation volume; and
D. Treatment volume below the lower operating level
for anaerobic treatment lagoons.
(6) Construction of Earthen basins.
(A) Geohydrologic Evaluation. A geohydrologic evaluation of
the proposed earthen basin prepared by the Missouri Geological Survey shall be submitted to the department. If the geohydrologic evaluation gives a severe rating for collapse potential,
an earthen basin shall not be used.
(B) Detailed Soils Investigation. A detailed soils investigation
is required to substantiate feasibility and to determine the
quantity and quality of soil materials on-site and from a borrow
area for use in the basin and/or liner. The following information, in whole or in part, is required:
1. Atterburg limits;
2. Standard proctor density (moisture/density relationships);
3. Coefficient of permeability (undisturbed and remolded);
4. Depth to bedrock;
5. Particle size analysis; and
6. Depth to groundwater table.
(C) Shape and Location.
1. The shape of all cells shall be such that there are no
narrow or elongated portions or islands, peninsulas, or coves.
2. The floor of the structure shall be a consistent elevation
with finished elevations not be more than three inches (3")
above or below the average elevation of the floor.
3. The floor of the basin shall be at least four feet (4') above
the groundwater table or the water table as modified by subsurface drainage and at least two feet (2') above bedrock.
(D) Outer berm slopes shall not be steeper than three to one
(3:1), horizontal to vertical, and inner slopes not be flatter than
four to one (4:1) or steeper than three to one (3:1) for uncovered
lagoons or two and one-half to one (2.5:1) for covered lagoons.
(E) Berm Construction and Width. Construction specifications shall include the following:
1. Compact soil used in constructing the basin floor (not including clay liner) and berm cores to between two percent (2%)
below and four percent (4%) above the optimum water content
and to at least ninety percent (90%) standard proctor density;
2. Use lifts for berm construction not exceeding twelve
inches (12") with a maximum rock size not exceeding one-half
(1/2) the thickness of the compacted lift; and
3. Construct the top width of the berm a minimum of eight
feet (8') for fill heights from fifteen to twenty feet (15'–20'), use
minimum top widths of ten feet (10') and for fill heights from
twenty to twenty-five feet (20'–25'), use minimum top widths
of twelve feet (12').
(F) Emergency Spillway. To prevent overtopping and cutting
of berms, an emergency overflow shall be provided that—
1. Has a minimum bottom width of ten feet (10') and a
minimum depth of one foot (1'); and
2. Is compacted and vegetated or otherwise constructed to
prevent erosion due to possible flow.
(G) Compacted Clay Liner.
1. Liner construction. Compacted clay liners shall be constructed to—
A. Be scarified and compacted to between two percent
(2%) below and four percent (4%) above the optimum water
content and to at least ninety percent (90%) standard proctor
density;
B. Be raised in lifts not exceeding six inches (6") with a
maximum rock size not exceeding one-half (1/2) the thickness
of the compacted lift;
C. Be maintained at or above the optimum water content until the basin is prefilled with water; and
D. Have a minimum thickness of twelve inches (12").
2. Permeability. All earthen basins shall be sealed so that
seepage loss through the seal is minimized and to meet the
following specifications:
A. Cover the floor and extend up the inner slope to
where the side slope intersects with the top of the berm;
B. Have a design permeability of the basin seal not
exceeding 1.0 x 10-7 centimeter per second (cm/sec). For soils
which have a coefficient of permeability greater than 1.0 ×
10-7 (cm/sec), unusual depth, or potable ground water contamination potential, liner thickness of more than twelve inches
(12") may be required. The following equation shall be used to
determine minimum seal thickness:
t = (H×K)/ 5.4 × 10-7cm/sec
where
K = permeability coefficient of the soil in question;
H = head (maximum water level depth) of water in the basin;
and
t = thickness of the soil seal.
(H) Protection of Berms. Rip-rap or some other acceptable
method of erosion control is required as a minimum around
all piping entrances and exits, for aerated cell(s), on the slopes
and floor in the areas where turbulence will occur, and for protection from wave action for basins with a surface area greater
than five (5) acres.
(I) If alternative liners are used, permeability, durability,
and integrity of the proposed materials must be satisfactorily
demonstrated for anticipated conditions.
(J) Depth Gauges. A permanent depth measurement gauge
or marker shall be installed and maintained in the basin that
is easily readable at one-foot (1') or smaller increments and
clearly displayed lower, upper, and emergency spillway levels.
(K) Piping. Fill around pipes installed through embankments
shall be compacted to prevent seepage and pressurized piping
must be valved. Valves are not required on gravity piping into
the lagoon.
(L) Safety. Consideration shall be given for safety in using
open storage structures including the use of prevention and
recovery components.
(M) Operation and Maintenance. An operation and maintenance plan is required addressing the major components of the
concentrated animal feeding operation system.
(7) Construction of Tanks and Pits. Construction of tanks and
pits shall meet the following requirements:
(A) Soils and Foundation. A thorough site investigation shall
be made to determine the physical characteristics and suitability of the soil and foundation for the fabricated storage structure. Position the floor of the below-ground storage tanks two
feet (2') above the groundwater table;
(B) Allow one foot (1') of depth at the top of covered structures for agitation and/or ventilation;
(C) Include a permanent depth measurement gauge or
marker that is easily readable at one-foot (1') or smaller increments for uncovered tanks and pits;
(D) Use perimeter tiling and granular backfill for below-ground pits;
(E) Locate tank and pit footings at or below the maximum
frost depth;
(F) Design concrete and steel features according to published
guidelines; and
(G) Design and construct tanks and pits to be watertight.
(8) Construction of Solid Manure Components. The following
requirements shall be met when constructing poultry buildings, open lots, stacking pads, stacksheds, and other similar
structures:
(A) Divert surface water away from animal confinement
areas and buildings;
(B) Floors and Pads. Construct the base of covered and uncovered lots, poultry buildings, and other solid manure storage
areas of concrete or other rigid, essentially watertight materials or from a firm, compacted, earthen base of Unified Soil
Classification System (USCS) class CH, MH, CL, GC, or SC soils a
minimum of two feet (2') above the groundwater table and be
at least two feet (2') above bedrock;
(C) Uncovered solids storage areas must also meet the following:
1. Have an overall slope between two percent (2%) and four
percent (4%) for unpaved lots;
2. Be maintained in a way that prevents ponding; and
3. Have a runoff collection structure that meets the requirements of this rule.
(9) Design and Construction of Pipelines, Pump Stations, and
Land Application Systems.
(A) General. Design of pipelines shall be based on the following requirements:
1. Ensure the storage/treatment facilities can be emptied
within the time limits stated in the nutrient management plan;
2. Convey the required flow without plugging, based on
the type of material and total solids content;
3. Install at a depth sufficient to protect against freezing;
4. Install with appropriate connection devices to prevent
contamination of private or public water supply distribution
systems and groundwater;
5. Size pumps to transfer material at the required system
head and volume;
6. Install a minimum of three feet (3') below the natural
stream floor and as nearly perpendicular to the stream flow as
possible;
7. Encase when buried under public roads; and
8. Separation from potable water lines. Pipelines shall
be located at least ten feet (10') horizontally from and at least
eighteen inches (18") below the base of any potable water line.
9. Aerial pipeline crossings of streams shall:
A. Provide support for all joints in pipes utilized in the
crossing;
B. Protect from the impact of flood waters and debris;
and
C. Be constructed so that they will remain watertight
and free from changes in alignment or grade.
(B) Gravity Pipelines. Design of pipelines shall be based on
the following requirements:
1. Use a minimum slope of one percent (1%) for four inch
(4") pipe, six-tenths percent (0.6%) for six inch (6") pipe, and
four-tenths percent (0.4%) for eight inch (8") pipe;
2. Design with clean-outs at a maximum interval of three
hundred feet (300') and with maximum horizontal curves of
ten degrees (10°) at pipe joints; and
3. Design gravity discharge pipes used for emptying a
storage/treatment structure with a minimum of two (2) valves
in series.
(C) Force Mains and Pressure Pipes. Design velocities shall be
between three (3) and six (6) feet per second.
(D) Testing. Hydro-pressure tests shall be made only after the
completion of backfilling operations and for a minimum of
one (1) hour using a minimum test pressure of the maximum
system operating pressure.
(E) Pump Stations.
1. Water supply protection. Manure pump stations shall
not be connected to a potable water supply and shall be located at least three hundred feet (300') from any potable water
supply well.
2. Alarm systems. Alarm systems are required for pumping
stations that are activated in cases of power failure, pump failure, or any cause of high water in the wet well.
(F) Land Application Systems. Land application systems shall
be designed with—
1. Spray application equipment specified that minimizes
the formation of aerosols;
2. The pumping system and distribution system sized for
the flow and operating pressure requirements of the distribution equipment and the application restrictions of the soils and
topography;
3. Provisions for draining the pipes to prevent freezing, if
pipes are located above the frost line;
4. A suitable structure provided for either a portable
pumping unit or a permanent pump installation, the intake
to the pumping system providing the capability for varying
the withdrawal depth, the intake elevation maintained twelve
to twenty-four inches (12"–24") below the liquid elevation, the
intake screened so as to minimize clogging of the sprinkler
nozzle or distribution system orifices, and, for use of a portable
pump, a stable platform and flexible intake line with flotation
device to control depth of intake;
5. Thrust blocking of pressure pipes; and
6. An automatic pump or engine shut-offs in case of pressure drop.
(10) General System Details.
(A) Mechanical Equipment. Mechanical equipment shall
be used and installed in accordance with manufacturers’
recommendations and specifications and major mechanical
units installed under the supervision of the manufacturer’s
representative.
(B) Potable Water Supply Protection. No piping or other
connections shall exist in any part of the concentrated animal
feeding operation system, which under any conditions, might
cause the contamination of a potable water supply.
(11) Mortality Management. Class I operations shall not use
burial as a permanent mortality management method to dispose of routine mortalities.
AUTHORITY: sections 640.710 and 644.026, RSMo 2016.* Original
rule filed July 14, 2011, effective April 30, 2012. Amended: Filed Jan.
26, 2016, effective Oct. 30, 2016. Amended: Filed June 15, 2018,
effective Feb. 28, 2019. Emergency amendment filed Dec. 8, 2020,
effective Dec. 22, 2020, expired June 19, 2021. Amended: Filed Jan.
8, 2021, effective Sept. 30, 2021.
*Original authority: 640.710, RSMo 1996 and 644.026, RSMo 1972, amended 1973,
1987, 1993, 1995, 2000, 2012, 2014.