Final Staff Report and Recommendations on Agricultural Burning



## Chapter 5

Emissions from Agricultural Burning

and Alternatives to Burning

and Health ConsiderationsFinal Staff Report and Recommendations on Agricultural Burning This page intentionally blank



## .San Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

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- 1 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning 

### Chapter 5: EMISSIONS FROM AGRICULTURAL BURNING AND ALTERNATIVES TO BURNING, AND HEALTH CONSIDERATIONS

Figure 5.1 Map illustrating PM2.5 Emissions in the Valley from Open BurningSan Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

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- 2 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning 5.1 DISTRIBUTION OF AGRICULTURAL OPEN BURNING EMISS IONS

The map on the previous page illustrates the tons o f PM2.5 emissions per square mile and existing and proposed biomass plants in th e San Joaquin Valley air basin (Valley). The Sectional divisions of the map are the 103 burn allocation zones as developed by the District for use in the s moke management system (SMS). Each zone in the map is marked to illustrat e the three-year average annual tons of PM 2.5 emissions per square mile gen erated from agricultural burning of all types for that zone between the year s of 2007 and 2009. Most of the burn allocation zones with the highest emission s from agricultural burning

have biomass facilities in or near them.

5.2 CURRENT EMISSIONS INVENTORY FROM AGRICULTURAL B URNING

For purposes of this report, the criteria pollutant s analyzed include volatile organic compounds (VOC), oxides of nitrogen (NOx), and particulate matter (PM2.5). The 2007 Ozone Plan control measure for O pen Burning (S-AGR-1) (Managed Burning and Disposal) pertains to the burn ing of any material including agricultural materials. The Plan identified the su mmer 2005 emissions inventory for open burning as 4.8 tons of NOx per day and 5.7 tons of VOC per day. In the winter, the 2008 PM2.5 Plan control measure for Ope n Burning (S-AGR-1) (Managed Burning and Disposal) identifies the 2005 emissions inventory for open burning as 8.16 tons of NOx per day, 10.70 ton s of PM2.5 per day and 0.19

tons of SO 2 per day. As shown in Figure 5-2, agricultural burn ing is concentrated

in winter months when PM2.5 is elevated and ozone v alues are relatively low.

Figure 5-2 Average Monthly Agricultural Burning (2007-2009)

0 10,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000

January

F eb r ua r y M arc h Ap r i l M ay June July

August

Se ptember October

N ovemb er DecemberBurn TonsSan Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

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- 3 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning Table 5-1 below presents the burn tons, burn acres, and tons of associated criteria pollutant emissions associated with agricu ltural burning averaged over a three year period for specific crop types and activ ities. The specific crop types and activities are the crops to be analyzed for the 2010 burn prohibitions resulting from state law. Because several crops ar e not a part of this analysis and do not pertain to this report, the data from th ose crops has been omitted

from the table below. The data for this table is t he best available information,

and came from the District SMS emission database.

Table 5-1 Average Annual Tons, Acres, and Emissions from Open Burning of the Remaining CH&SC Crop Types (2007-2009)
Emissions (Tons)

Crop Name Burn

Tons Burn

Acres NOx PM 2.5 VOC PM 10

Almond Pruning 51718 51718 152.57 173.26 134.47 18 1.01

Apple Pruning 900 391 2.34 1.66 1.03 1.75

Fig Pruning 1227 558 3.19 3.99 3.68 4.23

Pear Pruning 286 110 0.74 1.19 0.73 1.26

Pecan Pruning 501 295 1.30 1.83 1.58 1.96

Quince 47 28 0.12 0.17 0.15 0.18

Walnut Pruning 17083 14236 38.44 34.17 41.00 35.88

<20 Acre Orchard Removal (all crops) 70010 2334 182.03 255.54 220.53 273.04

Apple Orchard Removal 691 23 1.80 1.28 0.79 1.35

Citrus Orchard Removal 54035 1801 140.49 151.30 18 3.72 159.40

Fig Orchard Removal 2392 80 6.22 7.78 7.18 8.25

Pear Orchard Removal 490 16 1.27 2.03 1.25 2.16

Quince Orchard Removal 10 0 0.03 0.04 0.03 0.04

Brooder Paper <1 n/a 0.00 0.00 0.00 0.00

Diseased Beehives 90 41 0.20 0.68 0.48 0.71

Goat <1 n/a 0.00 0.00 0.00 0.003

Ponding/Levee Banks 302 139 0.68 2.29 1.62 2.40

Rice * 9049 3073 23.45 27.79 21.98 29.65

Raisin Trays 890 29683 1.90 0.33 1.94 0.35

Vineyard Removal 197140 13143 512.56 719.56 620.99 768.85

Totals: 406,861 117,668 1,069.3 1,384.9 1,243.2 1,472.5

* Note: no citrus pruning after 2005 1. Rice category includes residual rice straw, rice straw, rice stubble, and rice field levees.

Table 5-1 includes the Phase IV materials that were issued open burning permits. District staff calculated the burn acres and associated emissions from a

list of the amounts of selected Phase IV materials that were issued open burningSan Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

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- 4 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning permits, averaged from 2007-2009. The list include s almond pruning, walnut pruning, pecan pruning, vineyard removal, raisin tr ays, and rice stubble. The total acres burned from the three-year average of t he crops previously mentioned are 109,128 acres. The emissions from such activit ies are presented below:

Table 5-2 Average Annual Emissions From Open Burning of Selected Phase IV Crops (2007-2009)

Emissions NOx PM 2.5 VOC PM 10
Tons per Year 706.98 929.38 800.17 988.30

5.3 EXPECTED EMISSIONS FROM ALTERNATIVES (Criteria Pollutant – PM 2.5)

Pruning Materials The analysis in this report indicates that prunings from several crops will most likely be shredded on site, or already are shredded on site, as an alternative to open burning. The table below is a comprehensive c omparison of the average annual PM 2.5 emissions from open burn versus shred ding for the aforementioned crops. For purposes of this analysi s, District staff assumed the average burn acres would remain constant and that a ll burn acres would be

shredded on site.

The information for this analysis was derived by in putting the burn acre data from the “Average Annual Tons, Acres, and Emissions from Open Burning of Crops (2007-2009) table presented in Section 5-1 of this report into the District

Emissions Calculator. The District Emissions Calcu lator incorporates the emissions from various pieces of equipment, includi ng tractors and excavators associated with the activity, emissions from transf er and delivery vehicles, and other processes such as chipping, as well as the em ission factor for each crop type and activity. The data presented in the table below is a comprehensive emission inventory encompassing all aspects of the affected crops.San Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

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- 5 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning Table 5-3 Comparison of the Average Annual PM 2.5 Emissions From Open Burning and Shredding (2007-2009)

PM 2.5 Emissions (Tons)

Crop Name Burn

Acres Open Burn Shred

Almond Pruning 51718 203.0 4.8
Apple Pruning 391 3.5 0.1
Fig Pruning 558 4.8 0.1
Pear Pruning 110 1.1 0.01
Pecan Pruning 295 2.0 0.0

Quince 28 0.2 0.003
Walnut Pruning 14236 67.0 1.4

Total: 67336 281.6 6.4

Orchard Removal Materials The analysis in this report also indicated that sev eral crops are sent to the biomass facilities and will most likely continue to be sent to biomass facilities as biomass fuel as an alternative to open burning. Th e table below is a comprehensive comparison of the average annual PM 2 .5 emissions from open burn versus biomass processing for the aforemention ed crops. For purposes of this analysis, District staff assumed the average b urn acres would remain

constant and that all burn acres would be sent to t he biomass plant as fuel.

The information for this analysis was derived by in putting the burn acre data from the “Average Annual Tons, Acres, and Emissions from open burning of Crops (2007-2009) table presented in Section 5-1 of this report into the District

Emission Calculator. The District Emission Calcula tor incorporates the emissions created from various pieces of equipment, including tractors and excavators associated with the activity, emissions from transfer and delivery vehicles, and other processes such as chipping, as well as the emission factor for each crop type and activity. The data presente d in the next table is a comprehensive emission inventory encompassing all a spects of the affected

crops.

Table 5-4

Comparison of the Average Annual PM 2.5 Emissions From Open Burning and Biomass Operations (2007-2009 )

PM 2.5 Emissions (Tons)

Crop Name Burn

Acres Open Burn Biomass

<20 Acre Orchard Removal (all crops) 2334 264.2 32.8

Citrus Orchard Removal 1801 203.9 25.3
Fig Orchard Removal 80 9.1 1.1

Total: 4215 477.2 59.2San Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

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- 6 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning 5.4 EMISSION REDUCTION ANALYSIS

5.4.1 Introduction

The recommendations as described elsewhere in this report will result in greater curtailment of agricultural open burning currently allowed under District Rule

4103. The recommendations will result in the follo wing additional prohibitions:

Orchard Removals

• The prohibition of burning of all orchard removals from fig crops over 15 acres (District Rule 4103 currently allows burning at all acreage sizes).

• The prohibition of burning of all orchard removals for all crops (with the exception of citrus, apples, pears, and quince) wit h acreages over 15 acres up to and including 20 acres (District Rule 4103 cu rrently allows burning of acreages in this range).

Prunings

• The prohibition of burning of all orchard pruning material from fig crops for all acreages (District Rule 4103 currently allows burni ng at all acreage sizes).

• The prohibition of burning of prunings for each ag ricultural operation whose total nut acreage (i.e., almonds, walnuts, and peca ns) at all agricultural operation sites is 3,500 acres or more. For each a gricultural operation whose total nut acreage at all agricultural operation sit es is less than 3,500 acres, burning of up to 20 acres of prunings per year is a llowed plus additional acreage when a determination of economic hardship i s made by the District (District Rule 4103 currently allows burning at all acreage sizes).

The estimated emission reductions to be achieved by the new prohibitions listed above are presented in Table 5-5. Details of the e mission reduction analysis are discussed in the next section (Methodology and Calc ulations).San Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

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- 7 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning Table 5-5 Total Annual Emission Reductions from All New Open Burning

Prohibitions

Category Crop Nox (ton/year) PM2.5

(ton/year) VOC

(ton/year)

Figs 2.8 6.7 6.1

Orchard

Removals All Orchards

Less Than

20 Acres* 25.8 61.7 56.4

Figs 0.4 2.1 1.7

Almond 9.5 48.8 38.0

Pecan 0.0 0.1 0.1 Orchard Prunings

Walnut 0.7 3.7 2.9

Total 39.2 123.1 105.2

* except citrus, apples, pears and quince

5.4.2 Methodology and Calculations

Step 1: Determine the reduction in acreage which will be burned as a result of the new prohibitions

District staff analyzed information collected durin g 2007-2009 from the District’s Smoke Management System (SMS) in order to estimate the reduction in acreage of burning resulting from the new prohibitions. Th e SMS manages agricultural open burning in the San Joaquin Valley Air Basin (S JVAB) and collects and maintains information pertinent to the amount and t ype of material burned in the SJVAB. For each permitted open burning operation d uring the time period, the SMS identifies the specific item burned and the ass ociated acreage.

In order to estimate the reductions in acreage of o rchard burning resulting from each of the new orchard prohibitions listed, it was assumed that average annual acreage of permitted burns in the SMS for the perio d 2007-2009 is representative of the expected burning reduction for each category

. Extraction and analysis of data from the SMS for or chard removals yielded the following annual reductions in acres burned:San Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

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- 8 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning Table 5-6 Data from the SMS for Orchard Removal and Pruning

New Prohibition Annual

Reduction in Acreage Burned

Orchard removals from fig crops over 15 acres 61

Orchard pruning material from fig crops for all acr eages 557

Orchard removals for all crops (with the exception of citrus, apples, pears, and quince) 560

Almond pruning material 12,670

Pecan pruning material 22

Walnut pruning material 969

Step 2: Establish Applicable Emission Factors on a Per A cre Basis

Differential emission reduction factors for orchard removals and for orchard prunings, along with the basis for their developmen t, are presented in Tables 5-7 and 5-8 respectively of the cost and emissions sect ion of this staff report (Chapter 5).

Differential emission reduction factors for orchard removals (assuming 30 tons dry biomass per acre) are based on chipping and con version of the removed trees to biomass fuel rather than burning:

Differential

Emission

Factor (tons/acre) = Burning

Emission

Factor (tons/acre) - Chipping/Biomass

Emission Factor (tons/acre)

From Table 5-4 of the cost and emissions section th e differential emission factors

for orchard removals between 15 and 20 acres are:

NO

x 0.0460 tons per acre

PM 2.5 0.1101 tons per acre VOC 0.1007 tons per acreSan Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

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- 9 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning Differential factors for prunings (assuming 1 ton o f dry prunings per acre) are based on chipping and land incorporation of pruning s in lieu of burning:

Differential

Emission

Factor (lb/acre) = Burning

Emission

Factor (lb/acre) - Land

Incorporation

Emission Factor (lb/acre)

From Table 5-8 of the cost and emissions section th e differential emission factors for orchard prunings are:

NO

x 1.5 lb per acre

PM 2.5 7.7 lb per acre VOC 6.0 lb per acre

Step 3: Apply Applicable Emission Factor to Acreage Data Extracted from the

SMS

Tables 5-11 and 5-12 present the results for orchar d removals and prunings respectively.San Joaquin Valley Unified Air Pollution Control District May 20, 2010Revised July 21, 20105-10Chapter 5: Emissions from Agricultural Burning andAlternatives to Burning and Health ConsiderationsFinal Staff Report andRecommendations on Agricultural BurningTable 5-7Emission Reductions from New Orchard Removal ProhibitionsProhibitionNOx PM2.5 VOCCropCurrentPermittedOpenBurningNewProhibitionAcresReducedper SMSDifferentialEmissionFactor(ton/acre)AnnualEmissionReduction(tons)DifferentialEmissionFactor(ton/acre)AnnualEmissionReductiontons)DifferentialEmissionFactor(ton/acre)AnnualEmissionReductiontons)FigsPermittedat allacreagesProhibitedfor acreagegreater than15 acres61 0.046 2.8 0.1101 6.7 0.1007 6.1All other crops(with theexception ofcitrus, apples,pears, andquince)Permittedfor 20acres orLessProhibitedfor acreagegreater than15 acres560 0.046 25.8 0.1101 61.7 0.1007 56.4San Joaquin Valley Unified Air Pollution Control District May 20, 2010Revised July 21, 20105-11Chapter 5: Emissions from Agricultural Burning andAlternatives to Burning and Health ConsiderationsFinal Staff Report andRecommendations on Agricultural BurningTable 5-8Emission Reductions from New Orchard Pruning ProhibitionsProhibitionNOx PM2.5VOCCropCurrentPermittedOpenBurningNewProhibitionAcresReducedper SMSDifferentialEmissionFactor(lb/acre)AnnualEmissionReduction(ton)DifferentialEmissionFactor(lb/acre)AnnualEmissionReduction(ton)DifferentialEmissionFactor(lb/acre)AnnualEmissionReduction(ton)FigsPermittedat allacreagesProhibited forall acreages557 1.5 0.4 7.7 2.1 6.0 1.7Almond (surfaceharvested crop)Permittedat allacreagesProhibited foracreagegreater than20 acres12,670 1.5 9.5 7.7 48.8 6.0 38.0Pecan (surfaceharvested crop)Permittedat allacreagesProhibited foracreagegreater than20 acres22 1.5 0.0 7.7 0.1 6.0 0.1Walnut (surfaceharvested crop)Permittedat allacreagesProhibited foracreagegreater than20 acres969 1.5 0.7 7.7 3.7 6.0 2.9San Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

5-12 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning 5.5 HEALTH BENEFITS OF REDUCED OPEN BURNING

Given the minimal impact of open burning on ozone l evels in the Valley mentioned above, this discussion emphasizes the hea lth benefits of reduced open burning and associated PM 2.5 emissions. Prio r scientific studies as well as District experience have shown the importance of steadily reducing population exposure to PM 2.5 through controls on residential wood burning and open burning. The San Joaquin Valley experiences some o f the highest annual average concentrations of PM 2.5 in the nation. We ll-defined epidemiological relationships have been established between exposur e to elevated PM 2.5 and a range of health endpoints, including ischemic heart disease, asthma, chronic bronchitis, premature mortality, and others. The r egion can experience multi-day periods of atmospheric stagnation during which very little air mass is transferred in and out of the Valley. The net result can be a daily buildup of PM 2.5 levels, sometimes beyond the 24 hour federal standard of 35 μg/m 3

.

Unlike areas such as Southern California where PM 2 .5 levels are more distributed throughout the year, fine particulates are seasonally concentrated in the Valley. Because of this seasonal concentration effect, District controls currently imposed on open burning and residential w ood burning have had a disproportionate effect in reducing wintertime PM 2 .5 concentrations. In the case of residential wood burning, an external scientific evaluation was conducted by California State University (CSU) Fresno of Rule 49 01’s periodic curtailments (see www.cvhpi.org). This assessment found that as of the winter 2007-08 season (prior to the October 2008 amending of Rule 4901), daily curtailments coupled with reduced household wood burning overall had resulted in a 12.9%

and 13.6% reduction in annual PM 2.5 concentrations for Bakersfield and Fresno, respectively. Using the US EPA’s BenMAP mo del for calculating health benefits of reduced PM2.5 exposure, these reduction s translated into significant public health benefits, including significantly red uced cardiovascular disease, pulmonary disease, and pre-mature deaths.

A key element in this success has been the impositi on of restrictions in residential wood burning on days when meteorologica l conditions create the risk of health standard violations. Initially, as of No vember 1, 2003, that threshold

was established at the 1997 24 hr. PM 2.5 standard of 65 μg/m 3 . As amended in October 2008 for the 2008-09 winter season, that da ily curtailment threshold was substantially reduced to 30 μg/m 3 . That reduced curtailment threshold has benefited public health in three ways: First, it h as resulted in an absolute reduction in the total seasonal tonnage of resident ial wood burned. Second, it has insured that on days when wood burning is allow ed, each ton of emissions is more thoroughly diluted and dispersed, with attenda nt reductions in harmful peak exposures. And third, by restricting burning to da ys with reasonably goodSan Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

5-13 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning atmospheric dispersion, the formation of secondary aerosols such as ammonium nitrate during multi-day stagnation events is minim ized.

By restricting the analysis to the Bakersfield and Fresno/Clovis metro areas, the health evaluation of Rule 4901 (Wood Burning Firepl aces and Wood Burning Heaters) was made possible by a well-defined pre-an d post-Rule 4901 population exposure estimate for PM2.5. However, i n the case of health benefits from reduced burning under Rule 4103, it is not pos sible to replicate this analysis for several reasons. First, ambient monitors are g enerally not found in rural areas. In addition, the population density is cons iderably lower. As a result, estimating accurate population exposure reductions resulting from current or estimated reductions on agricultural burning is ver y difficult and not attempted

here.

However, it is possible to draw on the experience o f the District evaluation of

Rule 4901 to draw some reasonable conclusions that provide a public health justification for past and prospective reductions i n open burning under Rule 4103. First, the basin-wide emissions inventory for open burning and residential wood combustion are comparable. According to the 2008 C ARB emissions inventory, estimated tons per day (tpd) of PM2.5 from wood bur ned by households was 9.5 and 14.8 for agricultural material. Second, it is important to note at that as of December 2009, daily county-level curtailments of o pen burning are based on the same predicted 24 hr. 30 μg/m 3 concentration threshold used in Rule 4901. This means that a predominant source of rural and u rban open burn emissions has been eliminated on low dispersion days, with co rresponding reductions in overall exposure to individuals in areas where open burning is occurring, as well as minimizing exposure to secondary PM2.5.

Reduced emissions from Rule 4103 are presented belo w in Table 5-9. In a historical sense, reductions achieved to date repre sent a very rapid rate of emission decline in a given economic sector, with a ttendant health benefits to a more dispersed, rural population.

Table 5-9

Reductions in Criteria Pollutants Under Rule 4103 S ince 2004

NOx PM10 PM2.5 VOC CO Total Tonnage Reduction Since 2004 1,217 1,981 1,860 1,516 15,273

% Reduction Since 2004 48.9% 52.7% 52.6% 50.4% 48.5%

TPD Reduction Since 2004 3.3 5.4 5.1 4.2 41.8

Additional reductions anticipated under the amended Rule 4103 are shown above. The more modest reductions arising from the recommendations reflect the current balance of commodity profitability and costs for processing at biomass plants, as defined by the CH&SC. Past expe rience has shown that theSan Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

5-14 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning per unit costs of alternative disposal options with less environmental impacts tend to decline over time due to, in this case, new biomass plant capacity and the emergence of alternative disposal technologies. Th e District supports legislation that will encourage, promote and facilitate alterna tive uses for agricultural material as well as policies and initiatives that e ncourage renewable energy and energy efficiency including supporting legislation that provides additional biomass capacity utilizing agricultural materials. It is l ikely that the current constraints on open burning emission reductions imposed by the CH& SC will be reduced over time, with proportional health benefits.

5.6 HEALTH RISK ASSESSMENT OF OPEN BURNING AND

ALTERNATIVES

Often under the requirements of CEQA-mandated risk assessments, the District routinely employs several health risk assessment (H RA) models in order to estimate health risks posed by exposure to air poll utants from existing or hypothetical sources. These HRA models are based o n the following elements: (1) knowledge from prior scientific studies about t he relative toxicity of pollutants, (2) similar knowledge about the relative effects of increased concentrations of a given pollutant, (3) the hourly rate of emissions b y mass or parts per volume, i.e. emission factor, from a given source and the durati on of those emissions, (4) specification of meteorological conditions, (5) how the pollutants are dispersed and/or transformed in the atmosphere, (6) a gradien t or exposure surface that specifies various concentration levels at a given d istance from a source and time, (7) (in some cases) the spatial distribution and ch aracteristics of the exposed population, and (8) (in some cases) whether and how different sub-populations may be differentially affected such as children to a given level and duration of

exposure.

To evaluate the acute (short-term) and chronic (lon g-term) health impact of open burning of agricultural material and alternative di sposal methods, the following scenarios were analyzed (modeled):

Scenario 1: Open burning of prunings from 20 acres of nut trees. Emission

sources included diesel exhaust from equipment used to form the burn piles, and emissions from combustion of the or ganic material.

Scenario 2: Land incorporation of prunings from 20 acres of nut trees. Emission

source included diesel exhaust from equipment used to shred and incorporate prunings into the soil.

Scenario 3: Transfer of prunings from 20 acres of nut trees to a biomass facility.

Emission sources included diesel exhaust from equip ment used to collect and chip/shred prunings, diesel exhaust fro m trucks used to transport the chipped material to the biomass plant , diesel exhaustSan Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

5-15 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning from equipment used to unload and process the chipp ed material at the biomass plant, and emissions from the biomass c ombustor.

Scenario 4: Open burning of 20 acres of nut trees (orchard removal). Emission

sources included diesel exhaust from equipment used to form the burn piles and emissions from the combustion the or ganic material.

Scenario 5: Transfer of 20 acres of nut trees (orc hard removal) to a biomass

facility. Emission sources included diesel exhaust from equipment used to collect and chip/shred the orchard material , diesel exhaust from a truck used to transport the chipped material to the biomass plant, diesel exhaust from equipment used to unload and process the chipped material at the biomass plant, and emis sions from the

biomass combustor.

5.6.1 Methodology and Calculations

Emissions for each scenario evaluated were calculat ed using District-developed spreadsheets and the parameters listed below:

Table 5-10

Variables used to estimate scenario emissions

Variables Prunings Orchard

Removal Crop type Orchard Orchard Ag material (acres) 20 20 Material removed (tons/acre) 1 30 Roots removed (tons/acre) 0 1 Field equipment activity (hours/acre) 1 1 Power plant equipment activity (hours/acre) 2 2 Ag material delivered to power plant (tons/truck) 24 24

Round trip distance to power plant (miles) 100 100

Off-road diesel equipment was used to process crop material in the field and at the biomass facility. Off road equipment activity was modeled as an area source over the entire surface of the orchard or that port ion of the biomass facility used to receive and process wood chips. All particulate matter from off-road diesel equipment exhaust was modeled as diesel particulate matter (DPM). Relative risks generated by air contaminants from the open b urning of agricultural material were calculated using the California Air Resources Board (CARB) particulate matter speciation profile 450 for particulates, and emission factors from Lemieux, Lutes and Santoianni (2002) for volatile organic co mpounds. Emissions from open burn piles were modeled as point sources to al low for thermal loft from the heat of combustion. The open burning of orchard pr unings was assumed toSan Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

5-16 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning occur in four separate piles located at the souther n border of the orchard. The open burning of the orchard removal material was as sumed to occur in twenty piles evenly distributed within the orchard over a 24 hr. period. All particulate

matter from on-road diesel truck exhaust was modele d as DPM. On-road truck travel was modeled as a line source consisting of a one mile series of volume

sources.

To calculate pollutant dispersion and the resulting exposure gradient, the AERMOD model was used. Meteorological data for 200 4-2008 from Bakersfield was employed to determine the dispersion factors (i .e., the predicted

concentration or Χ divided by the normalized source strength or Q) fo r a receptor (human population) grid. These dispersion factors were input into the Hot Spots Analysis and Reporting Program (HARP) risk assessme nt module to calculate

the chronic and acute hazard indices as well as the carcinogenic risk for five

scenarios outlined above. No actual locations and nearby populations were used in the model analysis.

5.6.2 Health Risk Assessment Results

Worst case health risks for the open burning of agr icultural material and their alternatives are presented in Table 5-11 (pruning s cenario) and Table 5-12 (orchard removal scenario). The model results for open burning of prunings

show that the cancer risk and chronic hazard indice s are very low and not of concern for all disposal options. The acute hazard index in this case pertains to risk of an acute respiratory response over the shor t-term (24 hour) exposure generated by the burning of the prunings for a pers on standing within 25 meters of the burn piles. In this air pollutant modeling scenario, any acute hazard index score of over 1.0 indicates the potential for a neg ative impact on respiratory health. As shown, this threshold is not exceeded f or a maximum 24 hour. exposure scenario.

In the case of a worst-case health risk assessment for orchard removal options are shown in Table 5-11. As in the case of pruning s, cancer and chronic hazard indices for all options are very low values that do not indicate excessive risk. As shown in Figure 5-3, the open burning exposure scen ario is based on the assumption that removed trees are put into 20 piles , one per acre, and burned simultaneously. In this case, the acute hazard ind ex score for 24 hr. exposure in the zone nearest the burn piles is excessive (10.70 ). As one moves further from

the burn zone this relative hazard to short-term re spiratory health drops relatively quickly, falling by approximately 50% after 500 met ers and to an acceptable level of less than 1.0 after 1,000 meters.San Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

5-17 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning Table 5-11 Comparative Pruning Risk (20 Acres): Open Burning vs. Chipping/Shredding and Incorporation vs. Biomass Facility

Health Risk

Source Maximum

Individual Cancer

Risk 2
(x 10 -6 ) Acute Hazard

Index Chronic Hazard

Index

Orchard Burning 3.32 0.83 0.07 Land Incorporation 7.59 nc 1 nc Biomass Facility – Off Site

Orchard 9.69 nc nc

Transit 0.00 nc nc

Off Site Total 9.69 nc nc Biomass Facility – On Site Facility 0.10 0.00 0.00

Transit 0.00 nc nc

On Site Total 0.10 0.00 0.00

1 Acute and Chronic Hazard Indices were not calculat ed since there is no risk factor or the risk factor is so low that it has been determined to be insignificant for this type o f unit.

2 70 year exposure used.

Table 5-12 Comparative Orchard Burning Risk (20 Acres): Open Burning vs. Chipping/Shredding,

On-Site Biomass Facility vs. Off-Site Biomass Facil ity

Health Risk

Source Maximum

Individual Cancer

Risk 2

(x 10 -6 ) Acute Hazard

Index Chronic Hazard

Index

Orchard Burning 2.69 10.70 0.58 Biomass Facility – Off Site

Orchard 1.84 nc 1 nc
Transit 0.09 nc nc

Off Site Total 1.93 nc nc Biomass Facility – On Site Facility 0.55 0.00 0.00

Transit 0.09 nc nc

On Site Total 0.65 0.00 0.00

1 Acute and Chronic Hazard Indices were not calculat ed since there is no risk factor or the risk factor is so low that it has been determined to be insignificant for this type o f unit.

2 9 year exposure used.San Joaquin Valley Unified Air Pollution Control District May 20, 2010Revised July 21, 20105-18Chapter 5: Emissions from Agricultural Burning andAlternatives to Burning and Health ConsiderationsFinal Staff Report andRecommendations on Agricultural BurningFigure 5-3Acute Respiratory Risk Isopleths for Open Burning of Prunings (24 hr exposure)San Joaquin Valley Unified Air Pollution Control District May 20, 2010Revised July 21, 20105-19Chapter 5: Emissions from Agricultural Burning andAlternatives to Burning and Health ConsiderationsFinal Staff Report andRecommendations on Agricultural BurningFigure 5-4Acute Respiratory Risk Isopleths for Open Burning of Orchard Removal (24 hr exposure)San Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

5-20 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning There are a number of practices currently employed by District Compliance staff under the policy for Rule 4103 that are designed to minimize the potential health hazard of orchard removal burnings of this scale. The Appendix A (p. 7) from the Rule 4103 District Policy identifies the conditions that must be satisfied when District Compliance staff conduct their mandatory f ield site inspections prior to granting approval to proceed with burning:

Burn permits issued in rural residential areas , or in other areas where smoke may affect smoke sensitive areas, must include sitespecific instructions and permit conditions. The in structions and/or conditions must limit the possible smoke impact on nearby neighbors and/or smoke sensitive areas.

1. The permit applicant must be advised that only t hose materials produced along with the crop and listed on the burn permit may be permitted to burn.

2. Additional permit conditions may stipulate any o r all of the following:

a. The wind direction required at the time of ignit ion b. The burn site location on the property c. The day(s) of the week the burning may occur d. The time of day a burn may be ignited e. The time of day to cease burning or cease adding material to

the fire f. The size of the burn pile permitted to be burned at one time g. The permit will be issued for the duration of ne ed only.

Compliance Appendix A (p. 35) from the Rule 4103 Di strict Policy also makes explicit limits on burning in smoke sensitive areas with greater population

densities or facilities with sensitive individuals:

SMOKE SENSITIVE AREAS : Smoke sensitive areas are populated areas or other areas where smoke and air pollutants can adversely affect public health or welfare. These areas can in clude cities, towns, communities, campgrounds, trails, recreation al areas, hospitals, nursing homes, medical clinics, schools, day-care centers, roads and highways, airports, public event s, and shopping

centers.

A District on-site inspection is required near dens e populations or

smoke sensitive areas. If the District determines t here is a reason to believe smoke produced from a proposed burn may causeSan Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

5-21 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning complaints or create a nuisance, the burning may on ly be permitted under the following conditions:

A. The District must determine there is no other reasonable method of disposal.

B. The quantities of materials to be burned shall be limited as

needed.

C. The days burning may be authorized may be limit ed. For example, a burn site upwind from a school may have to limit burning to when school is not in session, such as o n weekends or during school vacation provided that no other sp ecial events or school functions are occurring during these off times.

D. Permittee must establish and provide an at-read y means to extinguish the fire if directed to do so by the Dis trict or any public officer.

E. Additional permit conditions may stipulate:

1. The wind direction required at the time of ignit ion. 2. The burn site location on the property. 3. The day(s) of the week the burning may occur. 4. The time of day a burn may be ignited. 5. The time of day to cease burning or cease adding material

to the fire. 6. The size of the burn pile and/or the number of b urn piles

authorized to burn at one time. 7. The permit will be issued for the duration of ne ed only.

F. If any of the conditions provided above cannot b e met, such burning shall not be permitted.

Because of these limitations, excess acute health r isks from orchard removals are minimized. As noted above, the overall traject ory of health risks from agricultural open burning has been following a stee p downward path since 2004.

The results of this health risk assessment undersco re the logic of (1) the current

balance stuck under the current CH&SC between the e conomic costs of alternatives to burning on the one hand and the pot ential health impacts of open burning on the other, as well as (2) the ongoing im portance of finding new incentives and technologies for the long-term elimi nation of open burning of agricultural materials.San Joaquin Valley Unified Air Pollution Control Di strict May 20, 2010 Revised July 21, 2010

5-22 Chapter 5: Emissions from Agricultural Burning and Alternatives to Burning and Health Considerations Final Staff Report and Recommendations on Agricultural Burning This page intentionally blank.