Imperial County Air Pollution Control District Rule 217

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RULE 217 LARGE CONFINED ANIMAL FACILITIES (LCAF) PERMITS REQUIRED

(Adopted 10/10/2006; Revised 2/09/2016)

A. General

A.1 Purpose

The purpose of this rule is to limit emissions of Volatile Organic 

Compounds (VOC) and Ammonia from Large Confined Animal Facilities 

(LCAF).

A.2 Applicability

This rule sets forth the permitting requirements for agricultural sources 

subject to permit as a result of amendments to California Health and 

Safety Code Section 40724.6 that became effective January 1, 2004. A 

written Permit to Operate shall be required for all Large Confined Animal 

Facilities.

B. Definitions

The following definitions apply to all terms applicable to this Rule. If a term is not

defined in this Rule, then the definitions provided in Rule 101 shall apply.

B.1 AERATED STATIC PILE (ASP): a system designed, constructed, 

maintained, and operated for decomposing organic material in which

the material is placed on top of perforated plates or pipes that are

connected to blowers that either push or pull air through the piles.

B.2 AEROBIC DIGESTER: a basin or tank designed, constructed,

maintained, and operated for the aerobic treatment of liquid or solid

manure that is approved by the APCD, ARB, and EPA.

B.3 AEROBIC LAGOON: a lagoon designed, constructed, maintained, and

operated in accordance with the applicable standards for aerobic

lagoons in the Natural Resource Conservation Service (NRCS)

California Field Office Technical Guide Conservation Practice Standard

Code 359 or other applicable standards approved by the APCD, ARB,

and EPA.

B.4 ALTERNATIVE MITIGATION MEASURES: a mitigation measure that is

determined by the APCD, ARB, and EPA to achieve reductions that

are equal to or exceed the reductions that would be achieved by

other mitigation measures listed in this rule that owners/operators

could choose to comply with rule requirements.
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B.5 ANAEROBIC DIGESTER: a basin or tank designed, constructed,

maintained, and operated for the anaerobic treatment of liquid or

solid manure in accordance with the applicable standards for

anaerobic digesters in the Natural Resource Conservation Service

(NRCS) California Field Office Technical Guide Conservation Practice

Standard Code 365 or 366 or other applicable standards approved by

the APCD, ARB, and EPA.

B.6 ANAEROBIC TREATMENT: the decomposition of organic matter by

microbes in the absence of oxygen. During this process four main

reactions occur. In the first reaction, complex organic materials (e.g.

carbohydrates, proteins, and fats) are hydrolyzed to form soluble

organic molecules (e.g. sugars, amino acids, and fatty acids). In the

second reaction, soluble organic molecules ferment to form acetic

acid, formic acid, and volatile fatty acids. In the third reaction, volatile

fatty acids undergo acetogenesis to form acetic acid and formic

acid. In the fourth reaction, acetic acid and formic acid undergo

methanogenesis to form methane and carbon dioxide.

B.7 ANAEROBIC TREATMENT LAGOON: a lagoon designed, constructed,

maintained, and operated in accordance with the standards for

anaerobic lagoons in the Natural Resource Conservation Service

(NRCS) California Field Office Technical Guide Conservation Practice

Standard Code 359 or other applicable standards approved by the

APCD, ARB, and EPA.

B.8 BEEF FEEDLOT: a CAF that is primarily concerned with raising

cattle for the production of meat for commercial purposes.

B.9 CDFA: California Department of Food and Agriculture or any person 

designed to act on its behalf. 

B.10 CEREAL GRAINS: grasses (members of the monocot families Poaceae 

or Gramineae) cultivated for the edible components of their fruit. These 

grains include corn, rice, wheat, barley, sorghum, millet, oats, rye, 

triticale, and fonio. For the purpose of this rule, buckwheat and quinoa will 

also be considered cereal grains. 

B.11 CERTIFIED NUTRITIONIST: a nutritionist certified by the American

Registry of Professional Animal Scientists or who is approved by the

APCD, ARB, and EPA.

B.12 COMPOSTING: the controlled biological decomposition of organic

material, under aerobic (with air) or anaerobic (without air) conditions,

to form a humus-like material.
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B.13 CORRAL: an area where animals are confined without separate stalls

in which the animals may rest. (also referred to as dry lot, pen,

exercise pen, loafing barn, saudi barn or open lot).

B.14 DAY: a twenty-four hour period beginning at 12:00 a.m. and ending at

midnight.

B.15 DRY MANURE/DRY SEPARATED SOLIDS: manure or separated

solids with less than 50% moisture, by weight, not including any

materials used for on-site composting operations.

B.16 DRY ROLLED CORN: any corn that is crushed between rollers

without previous treatment with steam or another softening process.

B.17 EMISSION MITIGATION PLAN: a document that lists and describes

all VOC mitigation measures to be implemented at the CAF.

B.18 FACILITY: a source or group of air pollution sources located on one

or more properties that are contiguous, adjacent, or separated only by

a public right-of- way and are under common ownership, common

control, or operated by entities that are under common ownership or

control. A facility includes, but is not limited to, all barns, buildings,

coops, corrals, feed storage areas, installations, milking parlors,

structures, and systems for the collection, distribution, storage, and

treatment of manure on the properties.

B.19 FEED BUNK: the area where feed is placed for the animals to eat the 

feed.

B.20 FEEDAPRON: the area in which the animal stands while eating feed. 

This area may also be referred to as a flush or scrape concrete lane. 

B.21 FREESTALL BARN: a structure for housing animals in which the

animals are contained in pens under a roof and have free access to

feed bunks, waterers, and stalls for resting.

B.22 HIGH MOISTURE CORN: corn which, at harvest, has a kernel moisture

of greater than 25%.

B.23 IN-CORRAL MOUNDS: mounds of manure and/or soil which are

constructed, designed, maintained, and operated by the

owner/operator to allow animals to have a dry area to lay and rest

during the wet season.

B.24 LAGOON: a basin constructed, maintained, and operated to store and 

treat manure. This does not include basins primarily used to collect
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runoff and storm water.

B.25 LARGE CAF: a CAF that maintains, on any one day, at least the

following number of animals:

B.26 LICENSED VETERINARIAN: a veterinarian licensed by the State of

California or a veterinarian that is approved by the APCD, ARB, and

EPA.

B.27 MATURE COW: a cow that has had at least one calf.

B.28 MILKING COW: a cow that is currently producing milk (lactating). 

B.29 MITIGATION MEASURE: an activity, practice, or technology that

reduces VOC air pollutants emitted by or associated with a CAF.

B.30 MAXIMUM ONE-TIME CAPACITY: the maximum number of animals at 

the facility in each production stage (facility capacity). 

B.31 MOLT: the periodic replacement of feathers by shedding old feathers 

while producing new ones. 

B.32 NRC: the National Research Council of the United States of America.

B.33 NRCS: the Natural Resource Conservation Service operated under

the United States Department of Agriculture.

B.34 PHOTOTROPIC LAGOON: a lagoon where at least 10% of the

bacteria in the lagoon are photosynthetic bacterium; the

bacteriochlorophyll a concentration is above 1081 g/L; or that is

Table 1 - Large CAF Definition By Livestock Category

Livestock Category Large CAF Definition

Beef Feedlots 3,500 beef cattle

Dairy 500 milking cows

Other Cattle Facility 3,500 calves, heifers, or other cattle 

Poultry Facility

 Chicken 400,000 head

 Duck 400,000 head

 Turkey 100,000 head

Swine Facility 3,000 head

Horses Facility 2,500 head

Sheep and Goat Facilities 15,000 head of sheep, goats, or any combination of the two

Any livestock facility not listed 

above 30,000 head
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designed, constructed, maintained, and operated according to other

standards approved by the APCD, ARB, and EPA.

B.35 POULTRY: any domesticated birds kept or raised for eggs or meat.

B.36 POULTRY LITTER: poultry excretions and bedding, including, but not

limited to, dried solids, manure, urine and bedding from chickens,

turkeys, geese, or ducks.

B.37 OVERALL VOC CAPTURE AND CONTROL

B.38 OXYGEN BARRIER FILM: a plastic film with an oxygen transfer rate not 

exceeding 200 cm3/(m2-24 hrs) as measured by ASTM D3985 or a 

plastic film with an equivalent oxygen transfer rate as determined by 

methods approved by the APCO and EPA. 

B.39 PHASE FEEDING: the feeding of multiple diets during the nursery stage 

and during the grower/finisher phase. 

B.40 PROCESSED CEREAL GRAIN OR PROCESSED CORN: cereal grains 

or corn that have undergone one or more processes to changes the 

underlying chemical structure compared to the cereal grain or corn as 

harvested. 

B.41 RAIN EVENT: precipitation greater than 0.1 inch in 24 hours at the

facility.

B.42 SEPARATED SOLIDS: solids removed from manure by a solid

separator system, not including any materials used for onsite

composting operations.

B.43 SHADE STRUCTURE: a structure designed, constructed, installed,

maintained, and operated to provide shade for livestock.

B.44 SOLID SEPARATOR SYSTEM: a system for separating solid manure

from the liquid manure stream that is designed, installed, constructed,

operated, and maintained in accordance with the applicable standards

in California NRCS Field Office Technical Guide Conservation

Practice Standard Code 632 or other applicable standards approved

by the APCD, ARB, and EPA. Solid separator systems may include, 

but are not limited to, flat belt separators, roller press separators, 

vibrating screen separators, stationary inclined screen separators, 

weeping walls, and settling basins.

B.45 SPLIT-SEX FEEDING PROGRAM: a feeding program that separates 

make and female swine after they are moved from the nursery and feed
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different diets to more closely match the nutrient requirements of the 

different sexes.

B.46 STEAM-FLAKED CEREAL GRAINS: cereal grain that is processed by

cooking the grain with steam under pressure and then flaking the

resulting material through heated rollers.

B.47 STEAM-FLAKED CORN: corn that is processed by cooking the corn

with steam under pressure and then flaking the resulting material

through heated rollers.

B.48 STORAGE POND: a basin constructed, maintained, and operated, to

store manure, after it has been treated or processed in a lagoon.

B.49 SWINE: for the purposes of this rule, and determination of the threshold

in Table 2, any weaned pig of at least forty-five (45) pounds in weight,

such as finishing pigs and breeding stock.

B.50 VOC CONTROL DEVICE: a device, into which captured air is vented,

that reduces the VOC content in the air prior to the air being released

into the atmosphere.

B.51 WEATHERPROOF COVERING/STORAGE STRUCTURE: A covering,

such as a building or tarp, constructed, installed, maintained, and

operated such that the material inside or underneath the covering is

not moved or moistened by weather conditions outside of the covering

including, but not limited, to wind and rain. The covering shall be

maintained according to manufacturer recommendations and adhere to

the applicable standards in NRCS California Field Office Technical

Guide (FOTG) Conservation Practice Standard Code 313 or other

applicable standards approved by the APCD, ARB, and EPA.

B.52 YEAR: any consecutive 365-day period.

C. Requirements

C.1 An Owner/operator shall obtain an Authority to Construct (ATC) or Permit 

to Operate (PTO) for the facility. Upon adoption of this rule, an owner or 

operator of a new or modified LCAF shall submit, for approval by the Air 

Pollution Control District (APCD), an Authority to Construct (ATC)/Permit 

to Operate (PTO) application for each LCAF. Additionally, each 

application shall include:

C.1.a The information that the APCD, or his designee, determines is 

necessary to prepare an emissions inventory of all regulated air 
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pollutants emitted from the operation, including, but not limited to, 

the provisions listed in C.1.b through C.1.e.

C.1.b List of all stationary combustion equipment. The applicant must 

provide the APCD with the frequency of equipment use, including 

year and model of the equipment, capacity (Btu/hr, horsepower, 

etc.), hours of usage each year, and/or gallon of fuel consumption 

to determine the baseline emission factors.

C.1.c List of all other significant sources of air pollution, including but not 

limited to, stationary irrigation pumps, gasoline storage tanks, etc.

C.1.d The maximum one-time capacity of the facility regardless if the 

facility is operating at full production at the time the application is 

submitted. 

C.1.e An Emissions Mitigation Plan that demonstrates that the facility will 

reduce emissions of VOCs and Ammonia, according to the 

requirements of Section C.5. In addition, owner/operator of any 

LCAF shall implement all emission mitigation measures as 

contained in the permit application on the day operations of a LCAF 

commence.

C.1.f In addition, the dust control plan for beef feedlots shall adhere to 

the requirements within Rule 420.

C.1.g The owner/operator of LCAFs that are not a dairy, beef feedlot, 

swine, or poultry operations shall submit an Emissions Mitigation 

Plan demonstrating facility-wide reductions of at least 30% or 

submit an Emissions Mitigation Plan that adheres to all the 

applicable requirements of sections C.5.

C.2 The APCD shall determine completeness for each ATC/PTO application 

according to the requirements contained within Rule 206, Section A.2. 

The APCD shall act upon an application pursuant to this rule within six 

months of receipt of a complete application.

C.3 Temporary Suspension of Mitigation Measures

An owner/operator may temporarily suspend utilization of a mitigation 

measure provided all of the following requirements are met:

C.3.a It is determined by a licensed veterinarian or certified nutritionist 

that the mitigation measure is detrimental to animal health or that 

suspension of the mitigation measure is necessary for the animal to 

molt, a signed, written copy of the determination shall be retained
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on-site and made available for inspection upon request, and

C.3.b The owner/operator notifies the APCD, within forty-eight (48) hours 

of the veterinarian’s or nutritionist’s determination that a measure is 

being temporarily suspended, and

C.3.c If such a situation exist, or is expected to exist for longer than thirty 

(30) days, the owner/operator shall, within that thirty (30) day 

period, submit another mitigation measure from the same section of 

the appropriate table to be implemented in lieu of the mitigation 

measure that suspended. Substituted measures shall be requested 

by submitting was an application to modify the mitigation plan.

C.3.d The APCD, ARB, and EPA approve the temporary suspension of 

the mitigation measure for the time period requested by the 

owner/operator and a signed written copy of this determination shall

be retained on-site. 

C.4 For each existing LCAF, three months after adoption of this rule, the 

owner or operator of a LCAF shall submit an Emissions Mitigation Plan 

that updates the information submitted pursuant to section C.1 and C.6. In 

addition, an owner/operator of an existing LCAF shall implement all 

emission mitigation measures as contained in the updated Emissions 

Mitigation Plan within 180 days of approval of this Rule. All modifications 

to LCAF’s shall follow Rule 207 procedures.

C.5 Facility Emission Mitigation Plan

The owner/operator shall submit a facility emission mitigation plan as part 

of the Permit to Operate application or Authority to Construct application. 

The mitigation plan shall contain the following: 

C.5.a The name, business address, and phone number of the 

owner/operator responsible for the preparation and the 

implementation of the mitigation measure listed in the mitigation 

plan. 

C.5.b The signature of the owner/operator attesting to the accuracy of the 

information provided and adherence to implementing the activities 

specified in the mitigation plan at all times and the date that the 

application was signed.

C.5.c A list of all the mitigation measures from Section C.6 that the 

owner/operator will use to comply with Rule 217 requirements; 

including the number of animals and acreage subject to each
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control, as applicable.

C.6 Owners/operators of LCAFs shall implement control measures identified in 

their Emissions Mitigation Plan which shall include those applicable 

mitigation measures from the appropriate tables as follows:

C.6.a Beef Feedlots: Owners/operators of a beef feedlot CAF shall 

comply with the mitigation measures in Table 2.1

Table 2.1 Beef Feedlot Mitigation Measures Requirements

A. Feed:

An owner/operator of a beef feedlot CAF shall implement at least two (2) of the 

following feed mitigation measures:

1. Feed according to National Research Council (NRC) guidelines.

2. Feed steam-flaked, dry rolled, cracked or ground corn or other steam-flaked, 

dry rolled, cracked or ground cereal grains.

3. Remove uneaten wet feed from feed bunks within twenty-four (24) hours after 

the end of a rain event.

4. Implement an alternative mitigation measure(s), not listed above.

B. Silage:

An owner/operator of a beef feedlot CAF that feeds silage shall implement at least 

one (1) of the following silage mitigation measures:

1.

Operators selecting this option must choose mitigation measure 1a plus 

one (1) from mitigation measures 1b, 1c, 1d plus two (2) from mitigation 

measures 1e, 1f, 1g:

a. Cover the surface of silage piles, except for the area where feed is being 

removed from the pile, with a plastic tarp that is at least five (5) mils thick 

(0.005 inches), multiple plastic tarps with a cumulative thickness of at least 5 

mils (0.005 inches), or an oxygen barrier film covered with a UV resistant 

material, within seventy-two (72) hours of last delivery of material to the pile.

Choose one of the following:

b. Build silage piles such that the average bulk density of silage piles is 

at least 44 lb/cu ft for corn silage and 40 lb/cu ft for other silage types, as 

measured in accordance with G; or

c. When creating a silage pile, adjust filling parameters to assure a calculated 

average bulk density of at least 44 lb/cu ft for corn silage and at least 40 lb/cu 

ft for other silage types, using a spreadsheet approved by the District; or

d. Incorporate all of the following practices when creating silage piles:

i. Harvest silage crop at ≥65% moisture for corn; and ≥60% moisture 

for alfalfa/ grass and other silage crops; and

ii. Incorporate the following parameters for Theoretical Length of Chop 

(TLC) and roller opening, as applicable, for the crop being harvested.
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Crop Harvested TLC Roller Opening 

(mm)

Corn with no Processing ≤ 1⁄2 in N/A

Processed Corn <35% dry matter ≤ 3⁄4 in 1-4 mm

Alfalfa/Grass ≤ 1.0 in N/A

Wheat/Cereal/Other ≤ 1⁄2 in N/A

iii. Manage silage material delivery such that no more than six (6) 

inches of material are un-compacted on top of the pile.

Choose two of the following:

e. Manage exposed silage (select one of the following):

i. Manage silage piles such that only one silage pile has an 

uncovered face and the uncovered face has a total exposed surface 

area of less than 2,150 square feet; or

ii. Manage multiple uncovered silage piles such that the total exposed 

surface area of all uncovered silage piles is less than 4,300 square 

feet.

f. Maintain silage working face (select one of the following):

i. Use a shaver/facer to remove silage from the silage pile; or

ii. Maintain a smooth vertical surface on the working face of the silage 

pile.

g. Silage Additives (select one of the following):

i. Inoculate silage with homolactic lactic acid bacteria in accordance 

with manufacturer recommendations to achieve a concentration of at 

least 100,000 colony forming units per gram of wet forage; or

ii. Apply propionic acid, benzoic acid, sorbic acid, sodium benzoate, 

or potassium sorbate at a rate specified by the manufacturer to reduce 

yeast counts when forming silage pile; or

iii. Apply other additives at specified rates that have been 

demonstrated to reduce alcohol concentrations in silage and/or VOC 

emissions from silage and have been approved by the District and 

EPA.

2. Utilize a sealed feed storage system (e.g., Ag-Bag) for silage.

3. Implement an alternative mitigation measure(s), not listed above.
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C. Housing:

An owner/operator of a beef feedlot CAF shall implement mitigation measures 1, 2, 3, 

and 4 and at least one (1) additional mitigation measure in each of the animal housing 

structures (e.g. each corral, etc.):

1.

a. Scrape corrals twice a year with at least ninety (90) days between 

cleanings, excluding the removal of in-corral mounds; and

b. Clean and remove manure from corrals every eighteen (18) months, 

including the removal of in-corral mounds. 

2.

Inspect water pipes and troughs and repair leaks at least once every seven 

(7) days.

3.

Choose one of the following:

a. Maintain corrals to ensure proper drainage preventing water from standing 

more than forty-eight (48) hours; unless standing water is the result of a rain 

event; or

b. Harrow, rake, or scrape corrals sufficiently to maintain a dry surface, 

unless the corrals have not held animals in the last thirty (30) days; except 

moisture may be permitted in areas underneath shade structures or where 

animals commonly congregate in large groups. 

4.

If the CAF has shade structures, they must choose with one of the following:

a. Install shade structures such that they are constructed with a light 

permeable roofing material; or

b. Install all shade structures uphill of any slope in the corral; or

c. Install shade structure so that the structure has a North/South orientation.

5.

Manage corrals and concrete lanes such that the dry manure depth in the pen 

does not exceed twelve (12) inches at any time or point, except for in-corral 

mounds. Manure depth may exceed twelve (12) inches when corrals become 

inaccessible due to rain events. The facility must resume management of the 

manure depth of twelve (12) inches or lower immediately upon the corral 

becoming accessible.

6.

Knockdown fence line manure build-up prior to it exceeding a height of twelve 

(12) inches at any time or point. Manure depth may exceed twelve (12) inches 

when corrals become inaccessible due to rain events. The facility must 

resume management of the manure depth of twelve (12) inches or lower 

immediately upon the corral becoming accessible.

7. Implement an alternative mitigation measure(s), not listed above.

D. Solid Manure/Separated Solids:

An owner/operator of a beef feedlot CAF that handles or stores solid manure or 

separated solids outside the animal housing shall implement at least one (1) of the 
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following mitigation measures:

1.

Choose one of the following:

a. Within 72 hours of removal from animal housing, either remove dry manure 

from the facility or, during those months where rain occurs, cover dry manure 

pile with a weatherproof covering, except for times, not to exceed twenty-four 

(24) hours per event, when wind events remove the covering; or

b. Manage moisture content of manure to less than 50%.

2. Implement an alternative mitigation measure(s), not listed above.

E. Liquid Manure:

An owner/operator of a beef feedlot CAF that handles manure in a liquid form 

shall implement at least one (1) of the following mitigation measures:

1. Use a phototropic lagoon.

2. Use an anaerobic treatment lagoon designed in accordance with NRCS 

Guideline No. 359.

3. Remove solids from the waste system with a solid separator system, prior to 

the waste entering the lagoon.

4. Maintain lagoon pH between 6.5 and 7.5.

5. Implement an alternative mitigation measure(s), not listed above.

F. Land Application:

An owner/operator of a beef feedlot CAF who land applies manure to crop land on the 

facility shall implement the following applicable mitigation measures:

1.

If the CAF applies solid manure, choose one of the following:

a. Incorporate all solid manure within seventy-two (72) hours of land 

application; or

b. Only apply solid manure that has been treated with an anaerobic treatment 

lagoon, aerobic lagoon, or digester system; or

c. Apply no solid manure with a moisture content of more than 50%; or

d. Implement an alternative mitigation measure(s), not listed above.

2.

If the CAF applies liquid manure, choose one of the following:

a. Only apply liquid manure that has been treated with an anaerobic 

treatment lagoon, aerobic lagoon, or digester system; or

b. Allow liquid manure to stand in the fields for no more than twenty-four (24) 

hours after irrigation; or

c. Apply liquid/slurry manure via injection with drag hose or similar apparatus; 

or

d. Implement an alternative mitigation measure(s), not listed above.

C.6.b Dairy CAF: An owner/operator of a large Dairy CAF shall comply 

with the mitigation measures in Table 2.2.
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Table 2.2 Dairy CAF Mitigation Measure Requirements

A. Feed:

An owner/operator of a dairy CAF shall implement mitigation measures 1, 2, 3, and 4 

and at least one (1) additional mitigation measure:

1. Feed according to National Research Council (NRC) guidelines.

2.

Push feed so that it is within three (3) feet of feedapron fence within two hours 

of putting out the feed or use a feed trough or other feeding structure 

designed to maintain feed within reach of the cows.

3. Begin feeding total mixed rations within two (2) hours of grinding and mixing 

rations.

4. Store grain in a weatherproof storage structure or under a weatherproof 

covering from October through May.

5. Feed steam-flaked, dry rolled, cracked or ground corn or other steam-flaked, 

dry rolled, cracked or ground cereal grains.

6. Remove uneaten wet feed from feed bunks within twenty-four (24) hours after 

the end of a rain event.

7. For total mixed rations that contain at least 30% by weight of silage, feed 

animals total mixed rations that contain at least 45% moisture.

8. Implement an alternative mitigation measure(s), not listed above.

B. Silage:

An owner/operator of a dairy CAF that feeds silage shall implement at least one (1) of 

the following silage mitigation measures:

1.

Operators selecting this option must choose mitigation measure 1a plus one 

(1) from mitigation measures 1b, 1c, 1d plus two (2) from mitigation measures 

1e, 1f, 1g:

a. Cover the surface of silage piles, except for the area where feed is being 

removed from the pile, with a plastic tarp that is at least five (5) mils thick 

(0.005 inches), multiple plastic tarps with a cumulative thickness of at least 

5 mils (0.005 inches), or an oxygen barrier film covered with a UV resistant 

material, within seventy-two (72) hours of last delivery of material to the 

pile.

Choose one of the following:

b. Build silage piles such that the average bulk density of silage piles is 

at least 44 lb/cu ft for corn silage and 40 lb/cu ft for other silage types, as 

measured in accordance with G; or

c. When creating a silage pile, adjust filling parameters to assure a calculated 

average bulk density of at least 44 lb/cu ft for corn silage and at least 40 lb/cu 

ft for other silage types, using a spreadsheet approved by the District; or

d. Incorporate all of the following practices when creating silage piles:

i. Harvest silage crop at ≥65% moisture for corn; and ≥60% moisture 

for alfalfa/ grass and other silage crops; and

ii. Incorporate the following parameters for Theoretical Length of Chop 
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(TLC) and roller opening, as applicable, for the crop being harvested.

Crop Harvested TLC Roller Opening

(mm)

Corn with no Processing ≤ 1⁄2 in N/A

Processed Corn <35% dry matter ≤ 3⁄4 in 1-4 mm

Alfalfa/Grass ≤ 1.0 in N/A

Wheat/Cereal/Other ≤ 1⁄2 in N/A

iii. Manage silage material delivery such that no more than six (6) 

inches of material are un-compacted on top of the pile.

Choose two of the following:

e. Manage exposed silage (select one of the following):

i. Manage silage piles such that only one silage pile has an 

uncovered face and the uncovered face has a total exposed surface 

area of less than 2,150 square feet; or

ii. Manage multiple uncovered silage piles such that the total exposed 

surface area of all uncovered silage piles is less than 4,300 square feet.

f. Maintain silage working face (select one of the following):

i. Use a shaver/facer to remove silage from the silage pile; or

ii. Maintain a smooth vertical surface on the working face of the silage 

pile.

g. Silage Additives (select one of the following):

i. Inoculate silage with homolactic lactic acid bacteria in accordance 

with manufacturer recommendations to achieve a concentration of 

at least 100,000 colony forming units per gram of wet forage; or

ii. Apply propionic acid, benzoic acid, sorbic acid, sodium benzoate, 

or potassium sorbate at a rate specified by the manufacturer to 

reduce yeast counts when forming silage pile; or

iii. Apply other additives at specified rates that have been 

demonstrated to reduce alcohol concentrations in silage and/or 

VOC emissions from silage and have been approved by the District 

and EPA.

2. Utilize a sealed feed storage system (e.g., Ag-Bag) for silage.

3. Implement an alternative mitigation measure(s), not listed above.

C. Milking Parlor:

An owner/operator of a dairy CAF shall implement at least one (1) of the 

following mitigation measures in each milking parlor:

1. Flush or hose milking parlor immediately prior to, immediately after, or 

during each milking.
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217-15

2. Implement an alternative mitigation measure(s), not listed above.

D. Freestall Barn:

An owner/operator of a dairy CAF that houses animals in freestalls shall implement 

mitigation measures 1 and 2 and at least one (1) additional mitigation measure in 

each freestall barn:

1.

Pave feedaprons, where present, for a width of at least eight (8) feet along the 

corral side of the feedapron fence for milk and dry cows and at least six (6) 

feet along the corral side of the feedapron for heifers.

2.

Choose one of the following:

a. Flush, scrape, or vacuum freestall flush lanes immediately prior to, 

immediately after, or during each milking; or

b. Flush or scrape freestall flush lanes at least three (3) times per day.

3.

Use non-manure-based bedding and non-separated solids based bedding for 

at least 90% of the bedding material, by weight, for freestalls (e.g. rubber 

mats, almond shells, sand, or waterbeds).

4.

For a large dairy CAF, remove manure that is not dry from individual cow 

freestall beds or rake, harrow, scrape, or grade freestall bedding at least once 

every seven (7) days.

5. Have no animals in exercise pens or corrals at any time.

6. Implement an alternative mitigation measure(s), not listed above.

E. Corrals:

An owner/operator of a dairy CAF that houses animals in corrals shall implement 

mitigation measures 1, 2, 3, 4, 5, and 6 and at least one (1) additional mitigation 

measure in each corral where animals have been housed in the last thirty (30) days:

1.

Pave feedaprons, where present, for a width of at least 8 feet along the corral 

side of the feedapron fence for milk and dry cows and at least 6 feet along the 

corral side of the feedapron for heifers.

2.

Choose one of the following:

a. Clean manure from corrals at least four (4) times per year with at least 

sixty (60) days between cleaning; or

b. Clean corrals at least once between April and July and at least 

once between September and December.

3.

Choose one of the following:

a. Scrape, vacuum, or flush concrete lanes in corrals at least once every day 

for mature cows and every seven (7) days for support stock; or

b. Clean concrete lanes such that the depth of manure does not 

exceed twelve (12) inches at any point or time.

4. Inspect water pipes and troughs and repair leaks at least once every seven 

(7) days.

5.

Choose one of the following:

a. Slope the surface of the corrals at least 3% where the available space for 

each animal is 400 square feet or less. Slope the surface of the corrals at 
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217-16

least 1.5% where the available space for each animal is more than 400 

square feet per animal; or

b. Maintain corrals to ensure proper drainage preventing water from standing 

more than forty-eight (48) hours; or

c. Harrow, rake, or scrape corrals sufficiently to maintain a dry surface.

6.

If the CAF has shade structures, they must choose one of the following:

a. Install shade structures such that they are constructed with a light 

permeable roofing material; or

b. Install all shade structures uphill of any slope in the corral; or

c. Clean manure from under corral shades at least once every fourteen (14) 

days, when weather permits access into the corral; or

d. Install shade structure so that the structure has a North/South orientation.

7.

Manage corrals such that the manure depth in the corral does not exceed 

twelve (12) inches at any time or point, except for in-corral mounding. Manure 

depth may exceed 12 inches when corrals become inaccessible due to rain 

events. The facility must resume management of the manure depth of 12 

inches or lower immediately upon the corral becoming accessible.

8.

Knockdown fence line manure build-up prior to it exceeding a height of twelve 

(12) inches at any time or point. Manure depth may exceed 12 inches when 

corrals become inaccessible due to rain events. The facility must resume 

management of the manure depth of 12 inches or lower immediately upon the 

corral becoming accessible.

9.

Choose one of the following:

a. Use lime or a similar absorbent material in the corrals 

according to the manufacturer's recommendation; or

b. Apply thymol to the feedlot soil in accordance with the manufacturer's 

recommendation.

10. Implement an alternative mitigation measure(s), not listed above.

F. Solid Manure/Separated Solids:

Owners/operators of a large dairy CAF that handle or store solid manure or separated 

solids outside the animal housing shall implement at least one (1) of the following

mitigation measures:

1.

Within seventy-two (72) hours of removal from housing, either:

a. Remove dry manure from the facility; or

b. Cover dry manure outside the housing with a weatherproof covering except 

for times when wind events remove the covering, not to exceed twenty-four 

(24) hours per event.

2.

Within seventy-two (72) hours of removal from the drying process, either:

a. Remove separated solids from the facility; or

b. Cover separated solids outside the housing with a weatherproof covering 

from October through May, except for times when wind events remove the 

covering, not to exceed twenty-four (24) hours per event.

3. Implement an alternative mitigation measure(s), not listed above.
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217-17

G. Liquid Manure:

An owner/operator of a dairy CAF that handles manure in a liquid form shall 

implement at least one (1) of the following mitigation measures:

1. Use a phototropic lagoon.

2. Use an anaerobic treatment lagoon designed in accordance with NRCS 

Guideline No. 359.

3. Remove solids from the waste system with a solid separator system, prior to 

the waste entering the lagoon.

4. Maintain lagoon pH between 6.5 and 7.5.

5. Implement an alternative mitigation measure(s), not listed above.

H. Land Application:

An owner/operator of a dairy CAF who land applies manure to crop land on the facility 

shall implement the following applicable mitigation measures:

1.

If the CAF applies solid manure, choose one of the following:

a. Incorporate all solid manure within seventy-two (72) hours of land 

application; or

b. Only apply solid manure that has been treated with an anaerobic treatment 

lagoon, aerobic lagoon, or digester system; or

c. Apply no solid manure with a moisture content of more than 50%; or

d. Implement an alternative mitigation measure(s), not listed above.

2.

If the CAF applies liquid manure, choose one of the following:

a. Only apply liquid manure that has been treated with an anaerobic 

treatment lagoon, aerobic lagoon, or digester system; or

b. Allow liquid manure to stand in the fields for no more than twenty-four (24) 

hours after irrigation; or

c. Apply liquid/slurry manure via injection with drag hose or similar apparatus; 

or

d. Implement an alternative mitigation measure(s), not listed above.

C.6.c Other Cattle CAF: Owners/Operators of an other cattle CAF shall 

comply with the mitigation measures in Table 2.3

Table 2.3 Other Cattle Mitigation Measure Requirements

A. Feed:

An owner/operator of an other cattle CAF shall implement at least two (2) of the 

following feed mitigation measures:

1. Feed according to National Research Council (NRC) guidelines.

2. Feed steam-flaked, dry rolled, cracked or ground corn or other steam-flaked, 

dry rolled, cracked or ground cereal grains.

3. Remove uneaten wet feed from feed bunks within twenty-four (24) hours after 

the end of a rain event.

4. Implement an alternative mitigation measure(s), not listed above.
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217-18

B. Silage:

An owner/operator of an other cattle CAF that feeds silage shall implement at least 

one (1) of the following silage mitigation measures:

1.

Operators selecting this option must choose mitigation measure 1a plus one 

(1) from mitigation measures 1b, 1c, 1d plus two (2) from mitigation measures

1e, 1f, 1g:

a. Cover the surface of silage piles, except for the area where feed is being 

removed from the pile, with a plastic tarp that is at least five (5) mils thick 

(0.005 inches), multiple plastic tarps with a cumulative thickness of at least 5 

mils (0.005 inches), or an oxygen barrier film covered with a UV resistant 

material, within seventy-two (72) hours of last delivery of material to the pile.

Choose one of the following: 

b. Build silage piles such that the average bulk density of silage piles is 

at least 44 lb/cu ft for corn silage and 40 lb/cu ft for other silage types as 

measured in accordance with G; or

c. When creating a silage pile, adjust filling parameters to assure a calculated 

average bulk density of at least 44 lb/cu ft. for corn silage and at least 40 lb/cu 

ft for other silage types using a spreadsheet approved by the District; or

d. Incorporate all of the following practices when creating silage piles:

i. Harvest silage crop at ≥65% moisture for corn; and ≥60% moisture 

for alfalfa/ grass and other silage crops; and

ii. Incorporate the following parameters for Theoretical Length of Chop 

(TLC) and roller opening, as applicable, for the crop being harvested.

Crop Harvested TLC Roller Opening 

(mm)

Corn with no Processing ≤ 1⁄2 in N/A

Processed Corn <35% dry matter ≤ 3⁄4 in 1-4 mm

Alfalfa/Grass ≤ 1.0 in N/A

Wheat/Cereal/Other ≤ 1⁄2 in N/A

iii. Manage silage material delivery such that no more than six (6) 

inches of material are un-compacted on top of the pile.

Choose one of the following:

e. Manage exposed silage (select one of the following):

i. Manage silage piles such that only one silage pile has an uncovered 

face and the uncovered face has a total exposed surface area of less 

than 2,150 square feet; or

ii. Manage multiple uncovered silage piles such that the total exposed 

surface area of all uncovered silage piles is less than 4,300 square feet.
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217-19

f. Maintain silage working face (select one of the following):

i. Use a shaver/facer to remove silage on the working face of the silage 

pile.

ii. Maintain a smooth vertical surface on the working face of the silage 

pile.

g. Silage Additives (select one of the following):

i. Inoculate silage with homolactic lactic acid bacteria in accordance 

with manufacturer recommendations to achieve a concentration of at 

least 100,000 colony forming units per gram of wet forage; or

ii. Apply propionic acid, benzoic acid, sorbic acid, sodium benzoate, or 

potassium sorbate at a rate specified by the manufacturer to reduce 

yeast counts when forming silage pile; or

iii. Apply other additives at specified rates that have been 

demonstrated to reduce alcohol concentrations in silage and/or VOC 

emissions from silage and have been approved by the District and EPA.

2. Utilize a sealed feed storage system (e.g., Ag-Bag) for silage.

3. Implement an alternative mitigation measure(s), not listed above.

C. Freestalls:

An owner/operator of an other cattle CAF that houses animals in freestalls shall 

implement mitigation measures 1 and 2 and at least one (1) additional mitigation 

measure in each freestall barn:

1. Vacuum, scrape, or flush freestalls at least once every seven (7) days.

2. Pave feedaprons, where present, for a width of at least six (6) feet along the 

corral side of the feedapron.

3.

Use non-manure-based bedding and non-separated solids based bedding for 

at least 90% of the bedding material, by weight, for freestalls (e.g. rubber 

mats, almond shells, sand, or waterbeds).

4.

Remove manure that is not dry from individual cow freestall beds or 

rake, harrow, scrape, or grade bedding in freestalls at least once every seven 

(7) days.

5. Implement an alternative mitigation measure(s), not listed above.

D. Corrals:

An owner/operator of a other cattle CAF that houses animals in corrals shall 

implement mitigation measures 1, 2, 3, 4, and 5 and at least one (1) additional 

mitigation measure in each corral where animals have been housed in the last thirty 

(30) days:

1. Scrape corrals twice a year with at least 90 days between cleanings, 

excluding in-corral mounds.

2.

Choose one of the following:

a. Scrape, vacuum, or flush concrete lanes in corrals at least once every 

seven (7) days; or

b. Clean concrete lanes such that the depth of manure does not 
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217-20

exceed twelve (12) inches at any point or time.

3. Inspect water pipes and troughs and repair leaks at least once every seven 

(7) days.

4.

Choose one of the following:

a. Slope the surface of the corrals at least 3% where the available space for 

each animal is 400 square feet or less. Slope the surface of the corrals at 

least 1.5% where the available space for each animal is more than 400 

square feet per animal.

b. Maintain corrals to ensure proper drainage preventing water from standing 

more than forty-eight (48) hours; or

c. Harrow, rake, or scrape corrals and corrals sufficiently to maintain a dry 

surface, unless the corrals have not held animals in the last thirty (30) days.

5.

If the CAF has shade structures, they must choose one of the following:

a. Install shade structures such that they are constructed with a light 

permeable roofing material; or

b. Install all shade structures uphill of any slope in the corral; or

c. Install shade structure so that the structure has a North/South orientation.

6.

Manage corrals and concrete lanes such that the dry manure depth in the pen 

does not exceed twelve (12) inches at any time or point, except for in-corral 

mounds. Manure depth may exceed twelve (12) inches when corrals become 

inaccessible due to rain events. The facility must resume management of the 

manure depth of twelve (12) inches or lower immediately upon the corral 

becoming accessible.

7.

Knockdown fence line manure build-up prior to it exceeding a height of twelve 

(12) inches at any time or point. Manure depth may exceed twelve (12) inches 

when corrals become inaccessible due to rain events. The facility must 

resume management of the manure depth of twelve (12) inches or lower 

immediately upon the corral becoming accessible.

8.

Choose one of the following:

a. Use lime or a similar absorbent material in the corrals according to the 

manufacturer's recommendation; or

b. Apply thymol to the feedlot soil in accordance with the manufacturer's 

recommendation.

9. Implement an alternative mitigation measure(s), not listed above.

E. Solid Manure/Separated Solids:

An owner operator of an other cattle CAF that handles or stores solid manure or 

separated solids outside the animal housing shall implement at least one (1) of the 

following mitigation measures:

1.

Within seventy-two (72) hours of removal from housing, either:

a. Remove dry manure from the facility; or

b. Cover dry manure outside the housing with a weatherproof covering from 

during those months where rain occurs, except for times when wind events 

remove the covering, not to exceed twenty-four (24) hours per event.
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217-21

2.

Within seventy-two (72) hours of removal from the drying process, either:

a. Remove separated solids from the facility; or

b. Cover separated solids outside the housing with a weatherproof covering 

from October through May, except for times when wind events remove the 

covering, not to exceed twenty-four (24) hours per event.

3. Implement an alternative mitigation measure(s), not listed above.

F. Liquid Manure:

An owner/operator of an other cattle CAF that handles manure in a liquid form 

shall implement at least one (1) of the following mitigation measures:

1. Use a phototropic lagoon.

2. Use an anaerobic treatment lagoon designed in accordance with NRCS 

Guideline No. 359.

3. Remove solids from the waste system with a solid separator separation 

system.

4. Maintain lagoon pH between 6.5 and 7.5.

5. Implement an alternative mitigation measure(s), not listed above.

G. Land Application:

An owner/operator of an other cattle CAF who land applies manure to crop land on 

the facility shall implement the following applicable mitigation measures:

1.

If the CAF applies solid manure, choose one of the following:

a. Incorporate all solid manure within seventy-two (72) hours of land 

application; or

b. Only apply solid manure that has been treated with an anaerobic treatment 

lagoon, aerobic lagoon, or digester system; or

c. Apply no solid manure with a moisture content of more than 50%; or

d. Implement an alternative mitigation measure(s), not listed above.

2.

If the CAF applies liquid manure, choose one of the following:

a. Only apply liquid manure that has been treated with an anaerobic 

treatment lagoon, aerobic lagoon, or digester system; or

b. Allow liquid manure to stand in the fields for no more than twenty-four (24) 

hours after irrigation; or

c. Apply liquid/slurry manure via injection with drag hose or similar apparatus; 

or

d. Implement an alternative mitigation measure(s), not listed above.

C.6.d Swine CAF: An owner/operator of a swine CAF shall comply with 

the mitigation measures in Table 2.4

Table 2.4 Swine Mitigation Measure Requirements

A. Feed:

Owners/operators of a swine CAF shall implement at least two (2) of the following 
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217-22

feed mitigation measures:

1. Use grain with an average particle size diameter between 300-800 microns.

2. Utilize phase feeding and split-sex feeding programs to more closely match 

the nutrient requirements of animals.

3. Implement an alternative mitigation measure(s), not listed above.

B. Housing:

Owners/operators of a swine CAF shall implement at least three (3) of the 

following mitigation measures in each animal housing unit:

1.

Use a slatted floor system (slatted floors over deep pits or shallow flush 

alleys), with daily manure removal for shallow flush alleys and weekly removal 

from deep pits.

2. Manage pens such that the manure depth in the pen does not exceed twelve 

(12) inches at any time or point.

3. Inspect water pipes and troughs and repair leaks at least once every seven 

(7) days.

4. Implement an alternative mitigation measure(s), not listed above.

C. Liquid Manure:

Owners/operators of a swine CAF that handle manure in a liquid form shall implement 

at least one (1) of the following mitigation measures:

1. Use a phototropic lagoon.

2. Use an anaerobic treatment lagoon designed in accordance with NRCS 

Guideline No. 359.

3. Maintain lagoon pH between 6.5 and 7.5.

4. Implement an alternative mitigation measure(s), not listed above.

D. Land Application:

Owners/operators of a swine CAF who land apply liquid manure to crop land on the 

facility shall implement one (1) of the following mitigation measures:

1. Allow liquid manure to stand in the fields for no more than twenty-four (24) 

hours after irrigation.

2. Implement an alternative mitigation measure(s), not listed above.

C.5.e Layer CAF: An owner/operator of a layer CAF shall comply with the 

mitigation measures in Table 2.5.

Table 2.5 Layer Mitigation Measures Requirements

A. Feed:

Owners/operators of a layer CAF shall implement at least one (1) of the following feed 

mitigation measures:

1.

Choose one of the following:

a. Feed according to NRC guidelines; or

b. Feed animals probiotics designed to improve digestion according to 
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217-23

manufacturer recommendations; or

c. Feed animals an amino acid supplemented diet to meet their nutrient 

requirements; or

d. Feed animals feed additives such as amylase, xylanase, and 

protease, designed to maximize digestive efficiency according to 

manufacturer recommendations.

2. Implement an alternative mitigation measure(s), not listed above.

B. Housing:

Owners/operators of a layer CAF shall implement at least two (2) of the following 

housing mitigation measures:

1. Use drinkers that do not drip continuously.

2. Inspect water pipes and drinkers and repair leaks daily.

3. Implement an alternative mitigation measure(s), not listed above.

C. Solid Manure/Separated Solids:

Owners/operators of a layer CAF that handle or store solid litter/manure or separated 

solids outside the animal housing shall implement at least one (1) of the following 

mitigation measures:

1.

Within seventy-two (72) hours of removal from housing, either:

a. Remove all litter/manure from the facility; and

b. Cover litter/manure outside the housing with a weatherproof covering 

during those months where rain occurs, except for times when wind events 

remove the covering, not to exceed twenty-four (24) hours per event.

2. Implement an alternative mitigation measure(s), not listed above.

D. Liquid Manure:

Owners/operators of a layer CAF that handle manure in a liquid form shall implement 

at least one (1) of the following mitigation measures:

1. Use a phototropic lagoon.

2. Use an anaerobic treatment lagoon designed in accordance with NRCS 

Guideline No. 359.

3. Maintain lagoon pH between 6.5 and 7.5.

4. Implement an alternative mitigation measure(s), not listed above.

C.6.d Broiler, Duck, or Turkey CAF: An owner/operator of a chicken 

broiler, duck, or turkey CAF shall comply with the mitigation 

measures in Table 2.6

Table 2.6 Broiler, Duck or Turkey Mitigation Measure Requirements

A. Feed:

Owners/operators of a broiler, duck, or turkey CAF shall implement at least one (1) of 

the following feed mitigation measures:
Imperial County Air Pollution Control District Rule 217

217-24

1.

Choose one of the following:

a. Feed according to NRC guidelines; orb. Feed animals probiotics 

designed to improve digestion according to manufacturer 

recommendations; or

b. Feed animals probiotics designed to improve digestion according to 

manufacturer recommendations; or

c. Feed animals an amino acid supplemented diet to meet their nutrient 

requirements; or

d. Feed animals feed additives such as amylase, xylanase, and 

protease, designed to maximize digestive efficiency according to 

manufacturer recommendations.

2. Implement an alternative mitigation measure(s), not listed above.

B. Housing:

Owners/operators of a broiler or duck CAF shall implement at least four (4) of 

the following housing mitigation measures:

Owners/operators of a turkey CAF shall implement at least five (5) of the following 

housing mitigation measures:

1.

Use a dry housing cleaning method at all times, except when a wet cleaning 

method is required for animal health or biosecurity issues, pursuant to Section 

C.1.e.

2. Use drinkers that do not drip continuously.

3. Inspect drinkers at least once every seven (7) days and adjust the height, 

volume, and location of drinkers if necessary.

4. Inspect water pipes and drinkers and repair leaks daily.

5. If the facility houses turkeys in pens, install mounds or berms up gradient to 

prevent the runoff of storm water into pens.

6. Implement an alternative mitigation measure(s), not listed above.

C. Solid Manure/Separated Solids:

Owners/operators of a broiler, duck, or turkey CAF that handles or stores solid 

litter/manure or separated solids outside the animal housing shall implement at least 

one (1) of the following mitigation measures:

1.

Within seventy-two (72) hours of removal from housing, either:

a. Remove all litter/manure from the facility; or

b. Cover litter/manure outside the housing with a weatherproof covering 

during those months where rain occurs, except for times when wind events 

remove the covering, not to exceed twenty-four (24) hours per event.

2. Implement an alternative mitigation measure(s), not listed above.

D. Liquid Manure:
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217-25

Owners/operators of a broiler, duck, or turkey CAF that handles manure in a liquid 

form shall implement at least one (1) of the following mitigation measures:

1. Use a phototropic lagoon.

2. Use an anaerobic treatment lagoon designed in accordance with NRCS 

Guideline No. 359.

3. Maintain lagoon pH between 6.5 and 7.5.

4. Implement an alternative mitigation measure(s), not listed above.

D. Exemptions

Except for the recordkeeping requirements of Section F, the provisions of this 

rule shall not apply to a CAF, which remains at all times below all of the 

regulatory thresholds in Table 3: 

E. Monitoring Requirements

Owners/operators shall comply with the requirements of Section E.1 when 

implementing all applicable Mitigation Measures in Section C.6.

E.1 Lagoon Monitoring

Owners/operators using a mitigation measure for a lagoon in their approved 

emissions mitigation plan shall monitor the lagoon for the required parameter(s), 

as determined by the District and EPA, at least once every calendar quarter, with 

at least 30 days between monitoring tests.

F. Administrative Requirements

F.1 Records for Exempt CAFs

Table 3 - Large CAF Definition By Livestock Category

Livestock Category Large CAF Definition

Beef Feedlots 3,500 beef cattle

Dairy 500 milking cows

Other Cattle Facility 3,500 calves, heifers, or other cattle 

Poultry Facility

 Chicken 400,000 head

 Duck 400,000 head

 Turkey 100,000 head

Swine Facility 3,000 head

Horses Facility 2,500 head

Sheep and Goat Facilities 15,000 head of sheep, goats, or any combination of the two

Any livestock facility not listed 

above 30,000 head
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217-26

An owner/operator claiming exemption pursuant to section D shall maintain 

records on a quarterly basis of the number and type of animals and production 

group at the facility. Examples of records that may be used to show proof of 

exemption include, but are not limited to, Dairy Herd Improvement Association 

records and animal inventories maintained for financial purposes.

F.2 General Records for CAFs Subject to Section C Requirements

F.2.a Permits: Owners/operators shall maintain copies of all facility 

permits.

F.2.b Number of Animals: Owner/operators shall maintain record s of the 

number of animals of each species and production group at the 

facility on a quarterly basis. Examples of records that may be used 

include, but are not limited to, Dairy Herd Improvement Association 

records and animal inventories done for financial purposes.

F.2.c Owner/operators shall maintain records sufficient to demonstrate 

compliance with all applicable mitigation measures.

F.3 Records for Feed and Silage Mitigation Measures

F.3.a Feed Content/Feed Additive: Records of feed content, formulation, 

and quantity of feed additive utilized, sufficient to verify compliance 

with approved feed content and feed additive mitigation measures. 

Records may include laboratory test results and other test results.

F.3.b Feed Processing: Records sufficient to verify that feed was given to 

animals (for example, put in feed bunks) or disposed of within the 

time allowed by the approved mitigation measure.

F.3.c Feed Removal: Records demonstrating that feed is removed within 

the specified time period.

F.3.d Feed Storage: Records demonstrating that feed was kept in 

weatherproof storage for the required period. Records for feed 

storage shall be required when implementing the mitigation 

measures.

F.3.e Feed Moisture Content: Records for annual testing to determine 

moisture content of mixed ration food that contains at least 30% by 

weight of silage. Records for feed moisture content shall be 

required when implementing the mitigation measures.
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F.3.f Silage Covers: Records demonstrating that silage was covered, 

including the thickness of the cover, in compliance with any silage 

mitigation measures chosen. Examples of records that show 

compliance include, but are not limited to, invoices demonstrating 

that silage covers were installed and maintained at the facility, 

cover thickness, records demonstrating the thickness of the silage 

cover, and maintenance records for repair or replacement of 

damaged covers.

F.3.g Silage Pile Bulk Density at Pile Formation: Records of required 

practices used to ensure adequate bulk density of silage piles 

and/or measured bulk density of silage piles. Records for silage 

bulk density shall be required when implementing the mitigation 

measures.

F.3.h Silage Pile Formation: Records demonstrating that silage piles were 

formed in compliance with any silage mitigation measures chosen. 

Examples of records that show compliance include, but are not 

limited to, moisture content of silage pile material, records of the 

length of cut for the crop being harvested, records of silage material 

delivery date, records that there are no more than six inches of 

material un-compacted on top of the pile of silage piles. Records for 

silage pile formation shall be required when implementing the 

mitigation measures.

F.3.i Silage Leachate: Records demonstrating that the leachate was 

collected either by an active or passive system and the system was 

maintained in a manner approved by the APCO and EPA. 

Examples of records that show compliance include, but are not 

limited to, design specification for the system and a maintenance 

checklist for inspections and repairs.

F.3.j Exposed Silage: Records demonstrating that silage piles are 

managed such that exposed surface area is in compliance with any 

silage mitigation measures chosen. Records for exposed silage 

shall be required when implementing the mitigation measures.

F.3.k Silage Inoculation: Records demonstrating silage inoculation with 

either homolactic lactic acid bacteria, propionic acid, benzoic acid, 

sorbic acid sodium benzoate, or potassium sorbate. Records shall 

include rate specified by manufacturer and rate applied by 

operator/owner, date of inoculation and date of silage pile formation 

completion. Records for silage inoculation shall be required when 

implementing the mitigation measures.
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217-28

F.3.l VOC Emission Control Systems: Source test results, 

monitoring/inspection logs and maintenance logs.

F.3.m Weatherproof Coverings: Records verifying that any covers used 

are installed, used, and maintained in accordance with 

manufacturer recommendations and any applicable standard 

approved by the APCO and EPA. For covers removed by wind 

events, an estimate of when the cover was removed and 

documentation of when the cover was replaced.

F.3.n Alternative Feed or Silage Mitigation Measures: Records sufficient 

to verify compliance with each approved alternative mitigation 

measure to the satisfaction of the APCO and EPA.

F.4 Records for Milking Parlor Mitigation Measures

F.4.a Records verifying that the milking parlor was flushed or hosed 

immediately prior to, immediately after, or during each milking.

F.5 Records for Freestall/Corral/Animal Housing

F.5.a Bedding Material: Records of the material(s) used for animal 

bedding, including the percentage of non-manure. Records for 

bedding material shall be required when implementing the 

mitigation measures.

F.5.b Clean/Scrape/Flush/Vacuum: Records sufficient to demonstrate that 

the removal of manure/bedding was performed as required in the 

approved mitigation measure. This may be a log when 

owners/operators initial that they performed all applicable practices.

F.5.c Depth of Manure: Records demonstrating the measurement of the 

manure depth and measures taken to remove material greater than 

the amount allowed by the mitigation measure.

F.5.d Foggers: Records, such as design specifications, demonstrating 

that foggers used to comply with rule requirements meet the 

required standards.

F.5.e Lime, Thymol, and Eugenol: Records of the quantity of material 

applied and the area over which it was applied. Owners/operators 

shall also maintain manufacturer’s product application 

recommendations to demonstrate compliance with the 

recommendations.
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217-29

F.5.f Litter Additives: Records, including a copy of the manufacturer’s

recommendations, which demonstrate litter additives used to 

comply with rule requirements are administered in accordance with 

manufacturer's specifications.

F.5.g Roof Structure/Runoff: Records such as design specifications and 

maintenance logs demonstrating that any roof runoff structures 

used to comply with rule are in compliance with applicable 

standards in NRCS Field Office Technical Guide Code 558 or other 

applicable standards approved by the APCO and EPA.

F.5.h Shade Structures: Records, such as design specifications, 

demonstrating that any shade structures used to comply with rule 

requirements meet the required standards.

F.5.i Slope/Drainage: Records sufficient to verify that harrowing and 

sloping of corrals used to comply with rule requirements are 

implemented as required in the rule.

F.5.j Vacuum/Land Apply Cattle Waste: Records showing time of 

vacuuming and time of land application of the vacuumed solids.

F.5.k VOC Emission Control Systems: Source test results, 

monitoring/inspection logs and maintenance logs.

F.5.l Water Pipes, Drinkers, and Water Troughs: Records of inspections 

performed and repairs completed.

F.5.m Wet Feed Removal: Records verifying that animal housing was

inspected for wet feed after a rain event/inspection and that the wet 

feed was removed.

F.5.n Alternative Freestall/Corral/Animal Housing Mitigation Measure: 

Records that demonstrate compliance with each approved 

alternative mitigation measure to the satisfaction of the APCO and 

EPA.

F.6 Records for Solid Manure/Separated Solids Outside of Animal Housing

E.6.a Aerated Static Pile: Records of monitoring/inspection logs and 

maintenance logs.

F.6.b Removal of Manure/Separated Solids: Records sufficient to verify 

when the waste was removed from freestall/corral/animal housing 

and when the waste was either removed from the facility or land 
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217-30

incorporated.

F.6.c Storage of Manure/Separated Solids in an Aerobic/Anaerobic 

Digester.

F.6.c.1 Records, such as design specifications and maintenance 

logs, demonstrating that any aerobic/anaerobic digesters 

used to comply with rule requirements meets the 

standards in NRCS Field Office Technical Guide Code 

366 or 365 or other applicable standards approved by the 

APCO and EPA.

F.6.c.2 Records of the quantity of manure/separated solids, as 

needed, to comply with the approved mitigation measure.

F.6.d VOC Emission Control Systems: Source test results, 

monitoring/inspection logs and maintenance logs.

F.6.e Weatherproof Coverings: Records verifying that any covers used 

are installed, used, and maintained in accordance with 

manufacturer recommendations and any applicable standard 

approved by the APCO and EPA. For covers removed by wind 

events, an estimate of when the cover was removed and 

documentation of when the manure/separated solid piles were recovered.

F.6.f Alternative Solid Manure/Separated Solids Mitigation Measure: 

Records that demonstrate compliance with each approved 

alternative mitigation measure to the satisfaction of the APCO and 

EPA.

F.7 Records for Liquid Manure

F.7.a Lagoons

F.7.a.1 Test results of the approved monitoring parameter and 

records of measures taken to bring the parameter within 

specified limits.

F.7.a.2 Design specifications demonstrating that the lagoon 

meets the requirements listed in the NRCS Field Office 

Technical Guide for the lagoon type or other applicable 

standards approved by the APCO and EPA.

F.7.b Solids Separator System
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217-31

F.7.b.1 Records, such as design specifications and maintenance 

logs, demonstrating that the solids separator system meets 

the approved mitigation measure specifications and is 

operated and maintained as recommended by the 

manufacturer.

F.7.b.2 Non-Standard Chemicals: Record the quantity of material 

used. Owners/operators shall also maintain manufacturer’s 

product usage recommendations to demonstrate 

compliance with the manufacturer’s recommendations.

F.7.b.3 Non-Standard Equipment for Solid Separator System: 

Records, such as design specifications and maintenance 

logs, demonstrating that the solids separator equipment 

meets the approved mitigation measure specifications and 

is operated and maintained as recommended by the 

manufacturer.

F.7.c VOC Emission Control Systems, including biofilters and other VOC 

emission control systems: source test results, monitoring/inspection 

logs and maintenance logs.

F.7.d Alternative Liquid Manure Mitigation Measures: Records that 

demonstrate compliance with the approved alternative mitigation 

measure, to the satisfaction of the APCO and EPA.

F.8 Records for Land Application of Manure

F.8.a Time to Incorporate Manure: Records indicating the time the 

manure was applied and when the waste was incorporated into the 

soil.

F.8.b Lagoon-Treated or Digester-Treated Manure: Records that 

demonstrate that the applied manure came from an aerobic lagoon, 

an anaerobic treatment lagoon or a digester system.

F.8.c Liquid Waste Standing in Field: Records that demonstrate that 

liquid manure does not remain in the field for longer than twentyfour (24) hours after application.

F.8.d Moisture Content of Solid Manure: Records of the moisture content 

of applied solid manure.

F.9 Source Testing Requirements
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217-32

F.9.a Owners/operators shall conduct an initial source test of all VOC 

control devices and aerated static piles used to comply with rule 

requirements not later than six (6) months after the date of 

installation, and at least once every twelve (12) months thereafter 

unless the APCO, ARB, and EPA determines more frequent testing 

is required to demonstrate compliance with rule requirements.

F.9.b Owners/operators using phototropic lagoons as a mitigation 

measure in their emission mitigation plan shall test lagoons for 

bacteria concentration, bacteriochlorophyll concentration, or a 

surrogate parameter determined by the APCO, ARB, and EPA not 

later than six (6) months after the date of issuance of the permit, 

and least once every twelve (12) months thereafter unless the 

APCO, ARB, and EPA determines more frequent testing is required 

to demonstrate compliance with rule requirements.

F.9.c Owners/operators using aerobic lagoons as a mitigation measure in 

their emission mitigation plan shall test lagoons for dissolved 

oxygen content not later than six (6) months after the date of 

issuance of the permit, and at least once every twelve (12) months 

thereafter, unless the APCO, ARB, and EPA determines more 

frequent testing is required to demonstrate compliance with rule 

requirements.

F.9.d Owners/operators using mechanically aerated lagoons as a 

mitigation measure in their emission mitigation plan shall test 

lagoons for biological oxygen demand within six (6) months after 

the date of issuance of the permit, and at least once every twelve 

(12) months thereafter, unless the APCO, ARB, and EPA 

determines more frequent testing is required to demonstrate 

compliance with rule requirements.

F.9.e Owners/operators using lagoon pH as a mitigation measure in their 

emission mitigation plan shall test lagoons for pH within six (6) 

months after the date of issuance of the permit, and at least once 

every twelve (12) months thereafter, unless the APCO, ARB, and 

EPA determines more frequent testing is required to demonstrate 

compliance with rule requirements. 

F.9.f Owners/operators shall test any other parameters determined 

necessary by the APCO, ARB, and EPA to demonstrate 

compliance with rule requirements as frequently as determined 

necessary by the APCO, ARB, and EPA.
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G. Test Methods

Owners/operators shall conduct applicable testing using the following methods or 

any other alternative test method approved by the APCD and EPA. Test methods 

referenced shall be the latest approved version.

G.1 Bacterial Concentration - ASTM D4454 - 85(2009) Standard Test 

Method for Simultaneous Enumeration of Total and Respiring 

Bacteria in Aquatic Systems by Microscopy or ASTM D4455 -

85(2009) Standard Test Method for Enumeration of Aquatic 

Bacteria by Epifluorescene Microscopy Counting Procedure.

G.2 Bateriochlorophyll a Concentration - ASTM D3731 - 87 (2004) 

Standard Practices for Measurement of Chlorophyll Content of 

Algea in Surface Waters.

G.3 Biological Oxygen Demand - EPA Method 405.1 (Biochemical 

Oxygen Demand (5 days, 20oC)).

G.4 Bulk Packing Density of Silage Piles - Remove representative 

samples of known volume using a forage probe or other instrument 

and weighing the samples. Bulk density is the weight of the sample 

divided by the volume of material removed from the pile. The bulk 

density shall be determined as the average of the least three 

representatives samples per silage pile.

G.5 Biofilter Control Efficiency - The control efficiency of a biofilter shall 

be determined using SCAQMD Method 25.3 (Determination of Low 

Concentration Non-Methane Non-Ethane Organic Compound 

Emissions from Clean Fueled Combustion Sources). The SCAQMD 

Method 25.3 apparatus should be connected to sample directly 

inside the flux chamber or duct as applicable. Compost emissions 

are considered as water soluble sources where the 50 ppm 

applicability limit of Method 25.3 does not apply. Samples from 

more than one location may be combined (composited) per 

SCAQMD Rule 1133.2 Attachment A Section 8. 

G.6 Non-Biofilter Control Efficiency - The control efficiency of a VOC 

emission control system that is not a biofilter shall be determined 

using:

G.6.a EPA Methods 2 (Determination of Stack Gas Velocity and 

Volumetric Flow Rate (Type s Pitot Tube), 2A (Volume 

Meters, or 2D (Rate Meters) for measuring flow rates. 
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217-34

G.6.b EPA Methods 25, 25A, or 25B for measuring total gaseous 

organic concentrations at the inlet and outlet of the control 

device.

G.6.c EPA Method 18 or ARB Method 422 shall be used to 

determine the emissions of exempt compounds.

G.7 Dissolved Oxygen - EPA Method 360.1 (Oxygen, Dissolved 

(Membrane Electrode)) or 360.2 (Oxygen, Dissolved (Modified 

Winker, Full-Bottle Technique)).

G.8 Moisture Content for Biofilters - Test Methods for the Examination 

of Compost and Composting (TMECC) Method 3.09 (Total Solids 

and Moisture at 70±5 degrees Centigrade).

G.9 Moisture Content for Silage - Soil, Plant and Water References 

Methods for the Western Region (Third Edition, 2005) Test 

Methods P1.10 (Dry Matter Content - Gravimetric), or American 

Association of Agricultural and Biological Engineers (ASABE) 

Standard S358.2, National Forage Testing Association (NFTA) 

Method 2.1.3 and 2.1.4 AOAC Methods: 930.15,934.01,991.01, 

and 2001.1.

G.10 Organic Loading - Standard Methods of the Examination of Water 

and Wastewater Method 2540G - Solids.

G.11 pH - EPA Method 150.2 (pH, Electrometric) or TMECC Method 

04.11-A (1:5 Slurry pH)

G.12 Temperatures - EPA Method 170.1 (Temperature - Thermometric)

G.13 Alternatives Test Methods - An operator may use an alternative test 

method to those listed in Sections G through G.12 for which written 

approval of the APCD and EPA has been obtained.

H. Compliance Determination 

H.1 Any violation of this underlying LCAF permit constitutes a violation of Rule 

217. 

H.2 Pursuant to District Rule 212, the APCD may update LCAF permits upon 

annual renewal, or as necessary, to include conditions necessary for 

compliance. 
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217-35

I. Annual Renewal Permits 

Annual Renewal Permits to Operate for LCAF shall be renewed according to the 

conditions set forth within Rule 206 and Rule 301.

J. Recordkeeping

All owners of confined animal facilities, regardless of size, shall keep records that 

specify the daily number and type of animals maintained at the facility in each 

production stage, the current ATC or PTO permit, the current Facility Mitigation 

Plan and other records necessary to demonstrate compliance. Current records 

shall be maintained and kept on-site for two years, except for major sources 

where records shall be maintained and kept on-site for 5 years, after the date of 

each entry and shall be presented to the APCD, or his designee, within 72 hours 

of notice to the owner or operator.

K. Public Review

Noticing prior to issuing any permit for LCAF, the draft permit shall be available 

for public review and inspection for a period of no less than 30 calendar days. To 

identify the location, the public notice shall include only the property address, city 

and state of the LCAF, as well as any other relevant permit information.

L. Non-duplication 

Information required to be submitted pursuant to other Air District Rules and 

Regulations that are applicable to a LCAF as determined by the APCD. 

M. Other Provisions 

Any permit issued to a LCAF is subject to all applicable provisions of the 

California Health & Safety Code and the Air District Rules and Regulations.