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AAQTF Agricultural Burning Policy Recommendations

AAQTF Recommendations Regarding Air Quality Policy on Agricultural Burning from November 10, 1999.

Recommendation from the Agricultural Air Quality Task Force to U.S. Department of Agriculture

November 10, 1999

Reference documents:

Attachment 1 (1.85 MB)
Attachment 2 (3.98 MB)

Executive Summary

The AAQTF Agricultural Burning Policy recommends States/Tribes adopt a Smoke Management Program (SMP) to reduce the public health and welfare impacts of using burning in support of agricultural production. The SMP is implemented through an Agricultural Burning Manager (ABM) The air quality agency or designated authority responsible for managing agricultural burning at the state, local, or tribal level. The policy is founded on two basic principles: (1) allow the use of fire as an accepted management practice, consistent with good science, to maintain agricultural production; and (2) protect public health and welfare by mitigating the impacts of air pollution emissions on air quality and visibility. The recommended SMP is two-tiered. De minimis fires, as established by the ABM, are exempt.

Tier One: Tier 1 is a voluntary program for areas where agricultural burning rarely causes or contributes to air quality problems. The SMP establishes conditions (time of day and year, meteorological conditions, safety parameters, type of burn, maximum number of acres, etc.) under which agricultural burning can occur. It is essentially a permit by rule.

Tier Two: Tier 2 is a more structured program than Tier 1 and is designed for areas where agricultural burning contributes to Particulate Matter National Ambient Air Quality Standards violations or visibility impairment in Class I Federal areas. (Areas set aside under the Clean Air Act to receive he most stringent protection from air quality degradation.) The SMP would include a process for authorizing/granting approval for agricultural burns and establish criteria for burn/no-burn decisions. Detailed permitting requirements such as a real-time meteorological assessment for bun decisions, air quality monitoring, public notification, and enforcement requirements would likely be included in a Tier 2 SMP.

The policy also recommends additional research in the following areas: the ability to predict downwind concentrations of particulate matter utilizing various modeling techniques; evaluating the applicability of current sampling techniques to agricultural burning; determining accurate emission factors; evaluating techniques to reduce emissions of material determined detrimental to human health and visibility; and developing alternatives to agricultural burning.



A. Role of Fire in Agriculture
B. Summary of Selected Agricultural Burning Practices
C. Air Quality Considerations
D. Current Regulations at State and Local Levels
E. Visibility Impairment


A. Tier I Smoke Management Program (Tier 1SMP)
B. Tier II Smoke Management Program (Tier 2 SMP)

1.  Authorized to Burn
2. Reducing Air Pollutant Emissions
3. Smoke Management Program Components
4. Producer/Public Education and Awareness
5. Surveillance and Enforcement
6. Program Evaluation

A. Dispersion Modeling
2.Long-range or Airshed
B. Emissions Factors
C. Emission Reduction Techniques
D. Health Effects
E. Sampling
F. Gas Emission Rate
G. Alternatives to Burning


Agricultural Burning: Burning in the open of vegetative materials from the production and harvesting of crops and animals for the purpose of marketing for profit, or providing a livelihood. This practice is generally used to reduce crop residue, stimulate yield, control diseases, reduce unwanted plant species, or otherwise maintain the productivity of agricultural lands.

Burning of small areas of land adjoining crop and rangeland for fire, weed, and disease control, etc. would fall under the definition of de minimis fires.

Agricultural Burning Manager: The Air Quality Agency or designated authority responsible for managing agricultural burning at the state, local or tribal level.

Agricultural Land: Land that includes croplands, rangelands (public or private), pasture and other lands on which crops or livestock are produced (P.L. 104-127, Sec. 1240A). This includes land enrolled in the Conservation Reserve Program.

Air Quality Agency: The regulatory body responsible for managing the air quality protection program for a state, local or tribal government.

Air Quality: The characteristics of the ambient air (all locations accessible to the general public) as indicated by concentrations of the six air pollutants for which national standards have been established, i.e., particulate matter (PM), sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), carbon monoxide (CO) and lead (Pb), and by visibility in mandatory Class I Federal areas. For the purposes of this policy, concentrations of particulate matter are taken as the primary indicators of ambient air quality.

Ambient Air: That portion of the atmosphere, external to buildings, to which the general public has access.

AP-42: The Environmental Protection Agency compilation of air pollutant emission factors for stationary point, area and mobile sources. An emission factor is a representative value that attempts to relate the quantity of a pollutant released to the atmosphere with an activity associated with the release of that pollutant. Emission factors are then used to estimate the magnitude of a source pollutant emissions.

Class I Federal Area: An area set aside under the Clean Air Act (CAA) to receive the most stringent protection from air quality degradation. Mandatory Class I Federal areas are: (1) international parks; (2) national wilderness areas which exceed 5,000 acres in size; (3) national memorial parks which exceed 5,000 acres in size; and, (4) national parks which exceed 6,000 acres and were in existence prior to the 1977 CAA amendments. The extent of a mandatory Class I Federal area includes subsequent changes in boundaries, such as park expansions.

De Minimis Fires: The maximum number of acres and/or tons of fuel allowed to be burned without a Smoke Management Program as established by the Agricultural Burning Manager on a case-by-case basis.

Indian Land: Indian land in this document refers to Indian country which is: (1) all land within the limits of any Indian reservation under the jurisdiction of the United States government, notwithstanding the issuance of any patent and, including rights-of-way running through the reservation; (2) all dependent Indian communities within the borders of the United States whether within the original or subsequently acquired territory thereof, and whether within or without the limits of a state; and, (3) all Indian allotments, the Indian titles to which have not been extinguished, including rights-of-way running through the same. [See 18 U.S.C. 1151.]

National Ambient Air Quality Standards (NAAQS): Standards for maximum acceptable concentrations of pollutants in the ambient air to protect public health with an adequate margin of safety and to protect public welfare from any known or anticipated adverse effects of such pollutants, e.g., visibility impairment, soiling, materials damage, etc., in the ambient air.

Particulate Matter (PM): Any airborne material, except uncombined water, which exists as a solid or liquid at standard conditions, e.g., dust, smoke, mist, fumes, or smog and can be divided into the following:

a. PM2.5: Particles with an aerodynamic diameter less than or equal to a nominal 2.5 micrometers;

b. PM10: Particles with an aerodynamic diameter less than or equal to a nominal 10 micrometers (including PM2.5);

c. Fine-Mode: Generally referred to as PM2.5;

d. Coarse-Mode: Generally referred to as PM10-PM2.5;

e. Ultra-Fine Mode: Generally referred to as equal to PM1 and below.

Pasture Land: Land used primarily for the production of adapted, introduced, or native forage plants for livestock grazing. Pasture land may consist of single species in a pure stand, grass mixture or a grass-legume mixture. Culture treatment in the form of fertilization, weed control, reseeding, or renovation is usually a part of pasture management in addition to grazing management. Native pasture is included.

Prescribed Fire: Any fire ignited by management actions to meet specific objectives, i.e., managed to achieve resource benefits.

Prevention of Significant Deterioration (PSD): A requirement in the CAA which establishes the maximum allowable increases in ambient air concentrations of selected air pollutants above baseline concentrations in designated Class I, Class II or Class III areas.

Rangeland: Land on which the climax vegetation (potential natural community) is predominantly grasses, grass-like plants, forbs, or shrubs suitable for grazing or browsing. Including natural grasslands, savannas, many wetlands, some deserts, tundra, and certain forbs and shrub communities. It also includes areas seeded to native or adapted introduced species that are managed like native vegetation.

Regional Haze: Generally, concentrations of fine particles in the atmosphere extending up to hundreds of miles across a region and promoting noticeably hazy conditions; wide-spread visibility impairment, especially in mandatory Class I Federal areas where visibility is an important value.

Smoke Management Program (SMP): Establishes a basic framework of procedures and requirements for managing smoke from fires that are managed for resource benefits. The purposes of SMP's are to mitigate smoke intrusions into populated areas and public safety hazards, e.g., on roadways and at airports, to prevent deterioration of air quality and NAAQS violations; and, to address visibility impacts in mandatory Class I Federal areas in accordance with the regional haze rule.

State Implementation Plan (SIP): A CAA required document in which States adopt emission reduction measures necessary to attain and maintain the NAAQS and to meet other requirements of the CAA.

Volatile Organic Compounds (VOCs): Any organic compound that participates in atmospheric photochemical reactions, which are measured by a reference method, an equivalent method, or an alternative method. Some compounds are specifically listed as exempt due to their negligible photochemical reactivity [see 40 CFR 51.100]. Photochemical reactions of VOCs with oxides of nitrogen and sulfur can produce ozone and particulate matter.

Wildfire: An unwanted wildland fire.

Wildland: An area where development is generally limited to roads, railroads, power lines and widely scattered structures. The land is not cultivated, i.e., the soil is disturbed less frequently than once in 10 years, is not fallow, and is not in the USDA Conservation Reserve Program (CRP). The land may be neglected altogether or managed for such purposes as wood or forage production, wildlife, recreation, wetlands or protective plant cover.

Wildland Fire: Any non-structural fire, other than prescribed fire, that occurs in the wildland. Note: wildland fires include unwanted (wild) fires and naturally ignited fires that are managed within a prescription to achieve resource benefits.


The Agricultural Burning Policy recommendations have been prepared in response to implementing provisions of the Clean Air Act (CAA) and the concerns of agricultural producers to retain the valid use of fire as a management tool in support of agricultural production. Fire has continued to be a management tool used by private and public land owners/producers for agricultural production and land management and, therefore, has a long-standing context in the planning and regulation requirements of Air Quality Agencies or Agricultural Burning Managers.

This Agricultural Burn Policy addresses two public policy goals: (1) to allow the use of fire as an accepted management practice, consistent with good science, to maintain agricultural production on agricultural land; and, (2) to protect public health and welfare by mitigating the impacts of air pollution emissions on air quality and visibility.

This policy provides guidance on reducing air pollution impacts caused by burning in support of agricultural production. It identifies a two-tier approach to the regulation of agricultural burning by Agricultural Burning Managers. This two-tier approach recognizes the large range of agricultural burning practices and their contribution to regional air quality.

The process used to develop this policy involves a multi-stakeholder approach. The USDA Agricultural Air Quality Task Force has developed recommendations using a consensus approach as outlined in a Memorandum Of Understanding (MOU) between the Secretary of Agriculture and the U.S. EPA Administrator (see Attachment I). The USDA Agricultural Air Quality Task Force includes representation from agricultural producers, air quality researchers, agricultural industry representatives, medical researchers and state air quality and USDA staff.


The EPA does not directly regulate the practice of agricultural burning within a state or on Indian lands.The EPA's authority is to enforce the requirements of the CAA. The CAA requires States and Tribes to attain and maintain the National Ambient Air Quality Standards (NAAQS) adopted to protect public health and welfare. This policy incorporates recommendations that States/Tribes implement smoke management programs (SMPs) to reduce the public health and welfare impacts of agricultural burning. It further recommends that SMPs be composed of a two-tier system as described in the Smoke Management Program in Section V.

This policy does not apply to wildland fires, or burning at residential, commercial, or industrial sites, or burning of construction debris. Wildland fires are addressed in the EPA's Interim Air Quality Policy on Wildland and Prescribed Fires.

This policy applies to the valid use of fire as a management tool in support of agricultural production. In addition, this policy addresses the impacts of air pollutant emissions as described by the NAAQS, on public health and welfare from agricultural burning practices. The NAAQS establish primary and secondary benchmarks for emission limitations for six criteria pollutants deemed by the EPA to endanger public health and welfare. The primary standards prescribe the maximum permissible concentration of a pollutant in the ambient air before it begins to impact public health. Secondary standards specify the level of pollutant concentrations that protect public welfare from any known or anticipated adverse effect(s). The pollutants addressed by the NAAQS include sulfur dioxide, particulate matter, carbon monoxide, ozone, nitrogen dioxide and lead.

Emissions from agricultural burning practices include: particulate matter with an aerodynamic diameter less than or equal to a nominal 2.5 micrometers (PM2.5); particles with an aerodynamic diameter less than or equal to a nominal 10 micrometers (PM10), nitrogen oxides (NOx); volatile organic compounds (VOCs); and, carbon monoxide (CO). Emissions from agricultural burning may also have an impact on ambient ozone concentrations.


A. Role of Fire in Agriculture

Fire has been an integral part of agricultural management as long as man has systematically grown crops. Modern technologically based agriculture still utilizes burning and for some crops it is the only economical means available to deal with residue.

The reasons for burning vary. The most common reasons are to reduce pre- and post-harvest vegetation that interferes with harvest, tillage or subsequent seedbed preparation. Burning is used for pest and weed control and lowers the need for supplemental herbicide and pesticide treatments. For example, the occasional burning of pruning and other vegetative debris are important controls for pest and disease in the orchard industry. Certain crops require burning to stimulate new growth and trigger higher yield, e.g., blue grass varieties, and strongly influence the economic sustainability of the grass seed industry. Burning is also used periodically to reduce fire hazard, e.g., on rangelands, weed infestation, and clogging of ditches and irrigation canals.

The following summary of crop burning practices and approximate acres burned are based upon the Technical Report submitted by Louisiana Commissioner of Agriculture and Forestry, Bob Odom, and attachments provided by Assistant Commissioner of Soil and Water (Louisiana Department of Agriculture and Forestry) Bradley E. Spicer. Dr. Jerry Lemunyon of Arlington, Texas compiled data on the burning of croplands with the assistance of USDA-NRCS staff.[1]

B. Summary of Selected Agricultural Burning Practices


Burning of sugarcane prior to harvest is utilized to deal with the approximately 30% residue portion of the plant. Of 50 tons of sugarcane about 15 tons of residue needs to be burned and there is no currently profitable or effective way to deal with this large volume of residue by mechanical means. Controlled cane burning allows more efficient harvesting in the field, controls insect problems and improves sugar quality and recovery in the factory. Harvesting burned cane results in less soil being brought to the mill; reduced fuel consumption in transporting less material; less water in washing the crop prior to milling; and, less waste, i.e., water, soil and trash, to recycle at the mill site. Reducing transport within the field lessens soil compaction and minimizes tillage, resulting in less damage to the soil structure and improved germination during the next crop cycle. Approximately 96% of the 890,000 acres of sugarcane grown in Florida, Louisiana, Hawaii, and Texas require burning.

Deciduous Fruits, Nuts, Grapes, Berries, etc.

Commercial crops grown on trees, vines, and bushes require pruning after crop harvesting. While the residue can be chopped or shredded for many crops, soil incorporation would damage shallow root systems. After the residue has dried, burning can be an effective means of disposal. Burning is also utilized as an effective means of disease control on new prunings to control secondary pests in the older residue and for phytosanitary emergencies.

In some areas smudge pots are used for frost protection in sensitive blooming species, but are being replaced by alternative frost protection systems, such as wind machines or sprinkler applications.

Burning of orchard residue is not the only means of disposal available. Approximately 5% of the 4.7 million acres of these crops are burned annually (Odom, 1997).


Significant acres of rice straw have been traditionally burned after harvest. This practice is declining due to air quality concerns and the development of techniques to incorporate rice straw into the soil. Burning may still be necessary for certain pest control and mechanical tillage does add to the cost of operation.

Approximately 20% of the 3.1 million acres of rice grown in Arkansas, Louisiana, California, Texas, Mississippi, and Missouri is burned annually.

Small Grains

In many parts of the country, small grain stubble is burned. The reasons for burning vary but generally fall into the category of residue removal, reducing the number of tillage operations for subsequent planting and periodic disease control, e.g., Cephalosporium. Alternative practices to burning are increasingly being utilized including short-stem varieties, minimum tillage practices and removal, i.e., baling of excess straw. Some additional costs may be incurred to the farming operation by these alternative practices, but on the other hand, there are benefits such as making it more feasible to use no-till seeding technology that reduce production costs.

Over 70 million acres are in small grain production in the United States. Not all States adequately track acres burned, but a conservative estimate of acres burned annually, is 7 to 8 million acres.

Rangeland and Pasture

Prescribed fire is used on rangeland and pasture to control undesirable plant species (particularly woody species), restore natural grassland communities, improve the quality and quantity of forage for livestock and wildlife, improve grass cover to protect the soil from erosion, and improve water yield from seeps and springs, among other things. Available alternatives such as mechanical brush control and chemical treatments (herbicides) can be expensive and detrimental to the environment given the large acres needing treatment.

Of the 1.9 billion acres of land in the contiguous United States, rangeland and pasture land account for about 725 million acres. Of this, about 200 million acres of rangeland are federally owned (525 million acres of private rangeland and pasture land); in contrast to United States cropland that is essentially all privately owned. Currently, there are not good estimates on how much private rangeland and pasture are burned annually. In Kansas, ranchers burn between 3 and 4.5 million acres each year. NRCS has estimated that nationally about 18 million acres of private rangeland and pasture need to be burned each year.

Grass Seed

Burning of grass seed fields is a long-standing practice that effectively removes residue, controls disease and stimulates tillering and flower formation that leads to higher yields. Grass seed production occurs in limited areas of suitable soil and climate, i.e., within the interior core area of the Pacific Northwest. Burning of grass fields is carried out in late summer and fall and is highly visible in those regions. Due to public pressure, grass burning is being phased out in Washington. Because of differing and changing regulatory policies, some inter-state movement of the grass seed industry is beginning to take place and in some instances, is happening at a fairly significant pace.

Alternative measures to grass burning include residue removal and shorter crop cycles. In addition, breeding programs are trying to develop new varieties that maintain yields without burning. Approximately 400,000 acres of grass seed fields are burned annually in the United States.

Miscellaneous Agricultural Activities, Corn and Other Row Crops, CRP, Ditch Cleanout, Land Clearing, etc.

Burning is occasionally used in other agricultural management practices. The Conservation Reserve Program (CRP) allows burning as an approved practice to decrease unwanted biomass or control pests. Burning is used extensively in small areas for wildfire control, weed and pest control in ditches, adjacent non-crop land areas and occasional minor land clearing. The individual acreage is small and the practice is often invaluable as an alternative to herbicide use on agricultural land and near watercourses. The NRCS estimates that approximately 2 million acres of CRP land is burned annually; about 2.5 million acres of non-crop land adjacent to agricultural operations is burned annually.


There are over 295 million acres of cropland harvested annually in the United States. Burning is used on approximately 3% (8.9 million acres) each year. Of the 600 million acres of grazing land in the continental United States, about 18 million acres need to be burned annually. An additional 2 million acres of CRP land and 2.5 million acres of irrigation ditches and other non-crop agricultural land areas require burning each year.

C. Air Quality Considerations

Burning of vegetative matter associated with agricultural land management produces emissions of PM10 and PM2.5. In addition, burning results in emissions of nitrogen oxides, carbon monoxide and organic compounds. The components and quantity of emissions depend on a variety of factors including type of fuel burned, fuel moisture content, ignition techniques, fuel conditions and temperature of combustion. The concentration of particulate matter in the air is also strongly influenced by local meteorological conditions including the low-level lapse rate, stability of the overlying atmosphere and velocity of transport winds above the surface.

Prior to 1987, the NAAQS for particulate matter focused on total Suspended Particles including particles as large as 100 micrometers in diameter. The EPA revised the standards in 1987 to focus control on PM10 in response to new science showing that it was the smaller particles capable of penetrating deeply into the lungs that were associated with the most adverse health effects. (Criteria Document - U.S. EPA, 1996a, p. 13-1). In 1997, the EPA set a �ine�particulate matter standard and is required to review and revise this standard, as necessary, along with all particulate matter standards by 2002.

D. Current Regulation at State and Local Levels

In many States (the south, southwest, intermountain west) agricultural burning is a long-standing vital practice that generally occurs in rural regions with low population densities. In general, these States regulate agricultural burning in the form of a "permit-by-rule" system. The Agricultural Burning Manager establishes a set of requirements under which burning can take place. These commonly include burner demographic information, crop type, acreage, etc., and permissible burning conditions, e.g., time of year, time of day, meteorological conditions, local notification, et al. If these conditions are met, the burning is allowed without any on-site ambient monitoring. Some states require written permits, while others do not. In other States, an Agricultural Burning Manager may determine if the daily meteorological conditions are appropriate to declare a burn or no-burn condition. A large proportion of agricultural burning is currently controlled under these types of regulatory processes where there is limited impact on urban airsheds.

In other States, e.g., California, Oregon, Eastern Washington, agricultural burning may impact urban airsheds. Although agricultural smoke is highly visible, its contribution to ambient concentrations of pollution in urban areas has not been objectively determined. Some States have regional airsheds that are prone to serious air stagnation conditions, e.g., the Willamette, Sacramento and San Joaquin Valleys. In these regions, agricultural burning may be a significant contributor to particulate matter. As a result, these States have curtailed and/or seriously regulated agricultural burning.

In doing so, an Air Quality Agency may identify local, regional or tribal Agricultural Burning Managers to establish detailed permitting requirements for burning, such as a SMP. The purpose of the SMP is to mitigate smoke intrusion and public safety hazard into populated areas by establishing procedures and requirements for agricultural burns being managed for resource benefits. The SMP should prevent a significant deterioration of air quality and prevent NAAQS violations. The Agricultural Burning Manager in these States will generally include specific permitting requirements for burners and may also specify a real-time meteorological assessment for burn decisions, air quality monitoring procedures, public notification, enforcement requirements and a detailed program assessment.

In some States, the local county or city government is encouraged to establish an air pollution authority, which may have far more stringent guidelines for agricultural burning than the Air Quality Agency. Some Air Quality Agencies use a permit-by-rule system. In short, the type and extent of burning requirements mandated at the state and local levels are broad ranging and responsive to the needs of a particular state or region, in addition to not unduly burdening the agricultural industry.

E. Visibility Impairment

Visibility is an important public welfare consideration because of its significance to the enjoyment of daily activities in all parts of the country. The scattering and absorption of light by particles and gases affect visibility conditions. High relative humidity can also affect visibility. Increasing humidity in the presence of airborne fine particulate matter is a factor in reducing visibility. Protection of visibility as a public welfare consideration is addressed through the secondary particulate matter NAAQS. Congress has established a national goal for visibility protection and remediation for mandatory Class I Federal areas. Currently, 156 national parks and wilderness areas have this designation.

The burning of vegetative matter associated with agricultural land management produces a range of particulate emissions and ozone precursors. Therefore, it has the potential to impact visibility in mandatory Class I Federal areas.

In 1980, the EPA published regulations (40 CFR 51.300) requiring the consideration of effects on visibility by nearby source(s) in mandatory Class I Federal areas. On July 1, 1999 the EPA final regional haze rule was published (64 FR 35713). It establishes a program to facilitate the integration of emission management strategies for regional haze with SIP components that address emissions of NOx, SO2,VOCs and PM2.5. The rule strongly encourages multi-state regional planning efforts to address the haze issue and Air Quality Agencies are moving forward with this effort.

This policy recommendation regarding agricultural burning that is managed for resource benefit encourages collaboration between owners/producers and Agricultural Burning Managers. The goals of the Agricultural Burning Policy are to: (1) allow fire to function as a valid tool for agricultural production; and, (2) protect public health and welfare by minimizing smoke impacts. Agricultural Burning Managers are urged to solicit information from private agricultural owners/producers on plans to use fire for resource management, to encourage appropriate alternative treatments, and to assist them in evaluating the potential air quality impacts of alternatives to meet particular management objectives.

Agricultural owners/producers are urged to: (1) consider the air quality impacts from fire and take appropriate steps to minimize those impacts; (2) consider appropriate alternative treatment and uses; and, (3) participate in the development and implementation of SMPs. This policy recommends a two-tier approach in the development of a SMP.

The EPA will allow Agricultural Burning Managers flexibility in their approach to regulating fires managed for agricultural resource benefits. Agricultural Burning Managers are not required to change their existing fire management policies/regulations if they adequately protect air quality. The following incentives exist for Agricultural Burning Managers to implement a SMP that includes the basic components outlined in this policy. The main incentive is that as long as the daily and annual PM2.5 and PM10 NAAQS are not violated by sources reasonably attributed to agricultural burning, the SMP is considered a voluntary action and does not have to be adopted into the SIP. Another incentive is the commitment that the EPA may use its discretion not to designate an area as nonattainment for particulate matter when fires reasonably attributable to agricultural burning contribute to violations of the particulate matter NAAQS if the fires were conducted under an approved Tier 2 SMP. If high concentrations of particulate matter arise from fires reasonably attributed to agricultural burning, the Agricultural Burning Manager will be required to review the adequacy of the SMP in cooperation with agricultural owners/producers and make appropriate improvements.


The SMP establishes a basic framework of procedures and requirements for managing smoke from fires greater than a de minimis level that are utilized for agricultural resource benefits. De minimis fires, as established by the Agricultural Burning Manager, are exempt from the requirements of the SMP. Agricultural Burning Managers typically develop SMPs in collaboration with agricultural owners/producers. The purpose of a SMP is to address public health and welfare concerns associated with smoke intrusions into populated areas; to mitigate deterioration of air quality and prevent NAAQS violations; and, to address visibility impacts in mandatory Class I Federal areas. Indications that an area needs a SMP include: (1) the trend of monitored air quality values is increasing, i.e., approaching the daily or annual NAAQS for particulate matter because of significant contributions of fires used for agricultural resource benefits; (2) fires used for agricultural resource benefits significantly contribute to visibility impairment in mandatory Class I Federal areas; and, (3) documented increase in the number of citizens experiencing smoke intrusions due to fires used for agricultural resource benefits. The SMP can include any type of program that the Air Quality Agency believes will prevent NAAQS violations and address visibility impairment in mandatory Class I Federal areas.

In order to receive special consideration of air quality data resulting from agricultural burning impacts under this policy, the Air Quality Agency must certify in a letter to the U.S. EPA Administrator that a SMP has been adopted and implemented. The SMP does not have to be incorporated into a State or Tribal Implementation Plan and is not federally enforceable.

A. Tier 1 Smoke Management Program (Tier 1 SMP)

A Tier 1 SMP is a voluntary program that is designed for those States, or those areas within a State, where agricultural burning for resource benefits rarely cause or contribute to significant air quality problems. A Tier 1 SMP would be indicated when pollutant emissions from agricultural burning are sufficiently dispersed in space and/or time in a region so that the guidelines of a Tier 1 SMP can effectively control smoke loading in an airshed and minimize the risk of air quality violations.

In a Tier 1 SMP, the Agricultural Burning Manager would establish the basic parameters and identify areas that would qualify as Tier 1 areas. The Tier 1 SMP would establish the basic conditions under which agricultural burning could occur. These conditions could include basic safety parameters, basic meteorological conditions, the type of agricultural burning/vegetative matter, the maximum number of acres to be burned and when the burning would occur (time of day and year). The land owners/producers may be asked to maintain information on the burn conditions established by the Agricultural Burning Manager.

B. Tier 2 Smoke Management Program (Tier 2 SMP)

A Tier 2 SMP is a voluntary program that is designed for those States, or those areas within a State, where agricultural burning for resource benefits would be expected to cause or significantly contribute to violations of the NAAQS or visibility impairment in mandatory Class I Federal areas. A Tier 2 SMP would be indicated when pollutant emissions from agricultural burning combine with geographic and meteorological conditions likely to result in air quality values that may exceed the NAAQS.

In a Tier 2 SMP, the Agricultural Burning Manager would be expected to establish a more structured set of parameters defining the level of voluntary cooperation and coordination needed from agricultural owners/producers. These parameters are designed to minimize air quality impacts to surrounding populated areas and the regional airshed in general. The Tier 2 SMP parameters should be flexible enough to handle the variety of air pollution concerns distinctive to each State (region) and the variability in crops and practices requiring burning.The following describes basic components of a Tier 2 SMP.

1.Authorization to Burn

The SMP should include a process for authorizing or granting approval to manage fires for agricultural benefits that identifies an Agricultural Burning Manager responsible for implementing the program. The Agricultural Burning Manager is responsible for consulting with land owners/producers and for establishing criteria for, and for authorizing burn and no-burn decisions. The criteria should include a timely evaluation of meteorological conditions, and existing air quality and dispersion conditions. Agricultural Burning Managers are encouraged to create partnerships to coordinate fire planning when regional interstate air quality impacts are anticipated. They are encouraged to coordinate with Federal Land Managers, Air Quality Agencies, private and agricultural landowners to take into consideration the spatial and temporal spacing of wildland and agricultural burns to avoid a concentration of burns in either time or location. The Agricultural Burning Manager should work with the Air Quality Agency so that the air quality monitoring system reflects sensitivity of receptors in the airshed for serious air quality impacts.

2. Reducing Air Pollutant Emissions

Agricultural Burning Managers should encourage agricultural owners/producers to consider alternatives to burning by providing results of research by federal and state agencies that demonstrate value-added alternatives for crop residue or economical alternatives to burning. When burning is utilized for agricultural resource benefits, Agricultural Burning Managers should cooperate with the owners/producers in identifying burning methods and determining alternative treatment strategies that can effectively reduce emissions on a per acre basis.

3. Smoke Management Program Components

The following components should be included in a SMP:
a. Identification of the distance and direction to local sensitive receptors both in state and interstate if appropriate;

b. Identification of actions that will be taken to notify sensitive populations and potentially affected communities and authorities prior to the fire;

c. Ownership, location and description of area to be burned;

d. Description of crop to be burned and reason for burning;

e. Number of acres to be burned;

f. Date of the anticipated burn; and,

g. Safety and contingency plans addressing smoke intrusions.

4.Producer/Public Education and Awareness

The Agricultural Burning Managers should implement an educational program to explain the use and importance of fire for agricultural systems, including information on smoke dispersion as it relates to meteorological conditions, ecosystems, sustainability and management goals, the potential implications of public health and safety, and the estimated duration of the burn. Other supplemental type information could include: agricultural burning fact sheets, a crop calendar on season activities of different crops that are subject to agricultural burning, and frequently asked question and answer documents.

Development of supplemental material should occur through a multi-agency/stakeholder process. Roles and responsibilities of each party involved in agricultural burning activities should be clearly identified in all documentation.

5. Surveillance and Enforcement

The SMP should include procedures to encourage agricultural owners/producers to comply with the requirements of the SMP and to explain any unintended consequences from the burn. Memorandums of Understanding should be encouraged between multi-agency/stakeholders to specify the responsibilities of each party in implementing the SMP.

6. Program Evaluation

The SMP should provide for the periodic review by all stakeholders of program successes, effectiveness and revision of the program as necessary. The review should be based on observations such as reports of smoke intrusions, public complaints, and air quality impacts on particulate matter and visibility.


The goal of research is to provide a sound scientific basis for decision-making. In general, the goal of reducing air pollution emissions has the ultimate objective of protecting public health and the ability of the public to enjoy the environment. In order to meet these goals the contribution from agriculture, specifically the impact of burning practices on regional air quality, must be accurately assessed in relative proportion to the region total emissions. It must be emphasized that this assessment be based on a sound scientific evaluation of measured air pollutants. To understand the impacts of air emissions on public health and welfare while simultaneously retaining the validity of agricultural burnings as a management tool requires further research. This research is centered in the following areas: the ability to predict downwind concentrations of particulate matter utilizing various modeling techniques; evaluating the applicability of current sampling techniques to agricultural burning; determining accurate emission factors; evaluating techniques to reduce emissions of those materials determined to be detrimental to human health and visibility; and when necessary and appropriate, developing alternatives to agricultural burning. The following are examples of areas of needed research:

A. Dispersion Modeling

1. Localized - Dispersion modeling is used to predict downwind concentrations of particulate matter from a source of pollutants. If the results from the model are not accurate, either the Air Quality Agency over-regulates the activity resulting in needed agricultural burning being disallowed or under-regulates the activity resulting in public health impacts from agricultural burning. A dispersion model is needed that will accurately estimate the contribution of PM10 and PM2.5 to the ambient concentration in the vicinity near the source. There have been reports that the EPA approved Gaussian models do not yield accurate estimates of downwind concentrations. In addition, dispersion modeling has been used in the past to estimate emission factors that are subsequently used in emission inventories. If the dispersion model inaccurately predicts downwind concentrations, it will not yield accurate emission factors for emission inventory purposes. New, more accurate dispersion air models are needed.

2. Long-range or Airshed - There is a need to more accurately estimate the long-range impacts of the pollutants resulting from agricultural burning. In other words, agricultural burning in one location may impact the PM10 concentration in a populated area or mandatory Class I Federal area miles away.

B. Emission Factors

Emission factors are used to estimate the rate that pollutants are entrained into the air relative to the activity rate. They are essential in the use of dispersion modeling to estimate downwind concentrations as a consequence of agricultural burning. Emission factors are also used to develop emission inventories. Inaccurate emission factors can result in over- or under-estimates of the contributions of a pollutant to ambient concentrations. These factors are multiplied times the agricultural burning area to yield mass of pollutants for emission inventory purposes. Orders of magnitude errors in emission factors can result in gross over- or under-estimates of the agricultural burning contributions that impact strategic air pollution regulatory approaches. Specifically, PM10 and PM2.5 emission factors from agricultural burning activities either do not exist or are not based on sound science. The EPA (1992) estimated emission factors for prescribed burning to range from 15 to 150 pounds of particulate matter per ton of fuel burned. The EPA also estimates that over 90% of the particulate matter emitted from agricultural burning activities is less than 10 micrometers.

C. Emission Reduction Techniques

Emission reduction technology to reduce the impact of pollutants emitted from agricultural burning on ambient concentrations is needed. Well-defined best available control measures (BACM) for different biomass, locations, time of the year, etc., are needed.

D.Health effects

Research is needed to characterize by size and compound the particulate material emitted from agricultural burning to determine the toxicity and impact on human health.


The measurement of particulate matter emission factors and concentrations in the vicinity of the agricultural burning (sampling) is not a simple task. The fire line is constantly moving. The rate of emissions is changing as a function of the variations in the biomass per unit area, wind velocity, fire temperature, meteorological conditions, etc. Research is needed to accurately measure the concentration of particulate matter from agricultural burning.

F. Gas Emission Rate

Research is needed to determine accurate emission factors and concentrations for CO, SO2, NOx, ammonia and VOCs. In addition, research is needed to determine the effect of controllable factors of agricultural burning on the emission rate of gases.

G. Alternatives to Burning

Research is needed on viable, economically feasible alternatives to agricultural burning to include value-added products from crop residues.