June 8, 2015

2012 PM2.5 Emission Estimates from Managed Burning and Disposal 

for the San Joaquin Valley Air Basin

Introduction

The recent 2015 San Joaquin Valley PM2.5 State Implementation Plan for the 1997 

standard (2015 PM2.5 SIP or 2015 SIP) showed a significant decline in PM2.5 emission 

estimates in the Managed Burning and Disposal category compared with previous 

inventories. This document provides an explanation of how emission estimates were 

derived for the 2015 PM2.5 SIP and a recent previous inventory, the Air Resources 

Board’s (ARB’s) Almanac of Emissions and Air Quality 2013 Edition (Almanac), and 

why these differences in emissions exist. Table 1 highlights the overall difference 

between PM2.5 emission estimates for the Managed Burning and Disposal category 

between the two inventories.

Table 1. San Joaquin Valley Managed Burning and Disposal, 2012 Annual 

Average PM2.5 Emissions in Tons/Day

2012 PM2.5 Emissions Almanac 2013 2015 PM2.5 SIP

Managed Burning and Disposal 13.9 3.0

Background on Inventory Versions

The Almanac is an emission inventory released periodically by ARB to provide a recent, 

quality assured emission inventory along with documentation to the general public. 

Almanac inventories are not used for SIP or regulatory purposes; however they often 

reflect the work of previous SIP efforts. The Almanac 2013 was officially released on 

February 20, 2014 and reflected ARB’s best estimate of California’s emissions at that

time.

The 2015 PM2.5 SIP was developed in 2014-2015 and includes many emission 

inventory updates since the publication of the Almanac 2013, including several in the

Managed Burning and Disposal category.

The Managed Burning and Disposal category is composed of several subcategories, 

which come from a variety of data sources. Table 2 shows a detailed breakdown of the 

subcategories which comprise Managed Burning and Disposal, showing more 

specifically where emissions have changed and the source of the emission estimates.
June 8, 2015

Table 2. Detailed Breakdown of Managed Burning Categories

2012 PM2.5 Emissions 

Annual Average tons/day

EIC Source Category Subcategory Almanac 2015 SIP Source

670-660-0262-9842 AGRICULTURAL BURNING - PRUNINGS ATTRITION 0.18 0.37

Reported 

by District

670-660-0262-9856 AGRICULTURAL BURNING - PRUNINGS GRAPE VINES/STUMPS 0.19 0.00

670-660-0262-9862 AGRICULTURAL BURNING - PRUNINGS ORCHARD REMOVAL 1.52 0.41

670-660-0262-9874 AGRICULTURAL BURNING - PRUNINGS RAISIN TRAYS 0.00 0.00

670-660-0262-9884 AGRICULTURAL BURNING - PRUNINGS TREE PRUNINGS 0.46 0.10

670-660-0262-9888 AGRICULTURAL BURNING - PRUNINGS UNTREATED GRAPE STAKES 0.01 0.00

670-660-0262-9892 AGRICULTURAL BURNING - PRUNINGS VINEYARD REMOVAL 1.78 1.05

670-662-0262-9866 AGRICULTURAL BURNING - FIELD 

CROPS

PAPER HOT CAPS 0.00 0.00

670-662-0262-9878 AGRICULTURAL BURNING - FIELD 

CROPS

RICE STUBBLE 0.10 0.04

670-664-0200-0000 RANGE IMPROVEMENT SUB-CATEGORY UNSPECIFIED 0.00 0.00

670-666-0200-0000 FOREST MANAGEMENT SUB-CATEGORY UNSPECIFIED 2.03 0.55 ARB

670-667-0200-0000 WILDLAND FIRE USE (WFU) SUB-CATEGORY UNSPECIFIED 7.08 --

670-668-0200-9858 WEED ABATEMENT NOXIOUS WEEDS 0.01 0.01

Reported 

by District

670-668-0200-9872 WEED ABATEMENT PONDING/LEVEE 

BANKS/DITCHBANK/CANAL

0.10 0.09

670-668-0200-9886 WEED ABATEMENT TUMBLEWEEDS 0.18 0.21

670-668-0200-9894 WEED ABATEMENT WEED ABATEMENT - OTHER 0.00 0.00

670-670-0200-0000 NON-AGRICULTURAL OPEN BURNING SUB-CATEGORY UNSPECIFIED 0.21 0.21

670-995-0240-9844 OTHER BROODER PAPER 0.00 0.00

670-995-0240-9846 OTHER DISEASED ANIMALS 0.00 0.00

670-995-0240-9848 OTHER DISEASED BEE HIVES 0.00 0.00

670-995-0240-9852 OTHER DISEASED FIELD CROPS 0.00 0.00

670-995-0240-9854 OTHER FERTILIZER SACKS 0.00 0.00

670-995-0240-9868 OTHER PESTICIDE/SEED SACKS 0.00 0.00

Total 13.9 3.0

Differences in emissions between the Almanac and the 2015 PM2.5 SIP estimates in 

specific subcategories are due to recent changes and updates, which are explained 

more thoroughly in the following sections:

Wildland Fire Use

The most significant change between the Almanac and 2015 PM2.5 SIP inventories 

occurs in the Wildland Fire Use (WFU) category. WFU’s are naturally ignited wildland 

fires that land management agencies manage for resource benefit. 

Starting in 2014, after the release of the Almanac, the WFU category was reclassified 

under Natural Sources. Inventories from this point forward, including the 2015 PM2.5 

SIP, will no longer have WFU emissions categorized under the Managed Burning and 

Disposal category. Table 3 highlights changes to WFU emissions as they are 

represented in the Almanac and 2015 PM2.5 SIP inventories. 
June 8, 2015

Table 3. Emissions and Reclassification of WFUs to Natural Sources

Almanac 2015 SIP

EIC Category Subcategory 2012 2012

670-667-0200-0000 MANAGED BURNING AND DISPOSAL WILDLAND FIRE USE (WFU) 7.08 --

930-667-0200-0000 NATURAL SOURCES - WILDFIRES WILDLAND FIRE USE (WFU) -- 13.98

Forest Management

The Forest Management category includes emissions from management burns (also 

known as prescribed or broadcast burns). These fires are ignited by a planned 

management action and typically administered by a public land management agency. 

The Forest Management subcategory shows a decrease of 1.5 tons/day of PM2.5 

between the Almanac and 2015 PM2.5 SIP estimates, as seen in Table 4.

Table 4. PM2.5 Emissions (tons/day) from the Forest Management Subcategory

Almanac 2015 SIP

EIC Category 2012 2012

670-666-0200-0000 FOREST MANAGEMENT 2.03 0.55

Forest Management emissions are estimated using the Emission Estimation System 

(EES) developed by UC Berkeley's Center for the Assessment and Monitoring of Forest 

and Environmental Resources (CAMFER). The EES implements the First Order Fire 

Effects Model (FOFEM 6.0) developed by the U.S. Forest Service (USFS) Fire Sciences 

Laboratory.

The emission estimate used in the Almanac inventory was based on a 10 year average 

of emissions from 1999-2008 using inputs from an interagency fire activity geodatabase 

maintained by the Fire and Resource Assessment Program (FRAP) of the California 

Department of Forestry and Fire Protection (CalFire). This category was updated in 

2014 to reflect a new 10 year average of emissions from 2001-2010 using inputs from 

an updated CalFire-FRAP geodatabase. This updated estimate was used for 2012 

emissions in the 2015 PM2.5 SIP.

Agricultural Burning

The remaining categories are estimated based on agricultural burning data reported by 

the San Joaquin Valley Air Pollution Control District. Emissions from these categories 

reflect crop specific burn activity and emission factors, as described in the included 
June 8, 2015

district methodologies. These methodologies are also published on the District’s 

website. Table 5 shows a detailed category breakdown along with emissions from the 

Almanac and 2015 PM2.5 SIP. 

Table 5. Emission Comparison for Agricultural Burning Subcategories

PM2.5 Emissions 2012

EIC Source Category Subcategory Almanac 2015 SIP

670-660-0262-9842 AGRICULTURAL BURNING - PRUNINGS ATTRITION 0.18 0.37

670-660-0262-9856 AGRICULTURAL BURNING - PRUNINGS GRAPE VINES/STUMPS 0.19 0.00

670-660-0262-9862 AGRICULTURAL BURNING - PRUNINGS ORCHARD REMOVAL 1.52 0.41

670-660-0262-9874 AGRICULTURAL BURNING - PRUNINGS RAISIN TRAYS 0.00 0.00

670-660-0262-9884 AGRICULTURAL BURNING - PRUNINGS TREE PRUNINGS 0.46 0.10

670-660-0262-9888 AGRICULTURAL BURNING - PRUNINGS UNTREATED GRAPE STAKES 0.01 0.00

670-660-0262-9892 AGRICULTURAL BURNING - PRUNINGS VINEYARD REMOVAL 1.78 1.05

670-662-0262-9866 AGRICULTURAL BURNING - FIELD CROPS PAPER HOT CAPS 0.00 0.00

670-662-0262-9878 AGRICULTURAL BURNING - FIELD CROPS RICE STUBBLE 0.10 0.04

Emissions are calculated using crop specific burn activity and emission factors as 

described in the district methodologies, and as seen in the following equation:

EmissionsPM10 = Tons Fuel × EFPM10

= Tons Fuel ×

lbs emissions

tons fuel ×

1 ton

2000 lbs

Typically, PM10 emissions are reported by the district, and then category specific 

speciation profiles are used to calculate the equivalent fraction of PM2.5:

EmissionsPM2.5 = EmissionsPM10 ×

PM2.5 size fraction

PM10 size fraction

Burn activity and emissions for year 2012 were reported to ARB by the District in March 

2014. These emissions were used to represent inventory year 2012 in the 2015 PM2.5

SIP.

Since emission calculations involve a large number of crop specific burn events and 

emission factors, only the two categories with the most significant changes in emissions 

will be broken down here. These are Orchard Removal and Vineyard Removal with a 

net change of -1.11 tons/day and -0.73 tons/day of PM2.5 respectively. Appendix A 

provides burn activity representative of these categories. Appendix B provides a 
June 8, 2015

complete list of emission factors by crop type. Tables 6 and 7 shows the steps used to 

calculate emissions for Orchard and Vineyard Removal.

Table 6. Agricultural Burning - Prunings - Orchard Removal (670-660-0262-9862)

County Crop Code Crop_Name

Activity

(tons) PM10 EF

PM10 EMS

(tons/day)

PM2.5/PM10

Fraction

PM2.5 EMS

(tons/day)

Fresno 189 Orchard removal < 15 acres 13170 7.80 0.141 0.943 0.133 

Fresno 190 Citrus Orchard Removal 1200 5.90 0.010 0.943 0.009 

Kern 189 Orchard removal < 15 acres 810 7.80 0.009 0.943 0.008 

Kings 189 Orchard removal < 15 acres 900 7.80 0.010 0.943 0.009 

Madera 189 Orchard removal < 15 acres 1500 7.80 0.016 0.943 0.015 

Merced 189 Orchard removal < 15 acres 5250 7.80 0.056 0.943 0.053 

San Joaquin 189 Orchard removal < 15 acres 1140 7.80 0.012 0.943 0.011 

Stanislaus 189 Orchard removal < 15 acres 2070 7.80 0.022 0.943 0.021 

Tulare 189 Orchard removal < 15 acres 9720 7.80 0.104 0.943 0.098 

Tulare 190 Citrus Orchard Removal 6600 5.90 0.053 0.943 0.050 

Total 0.41 

Table 7. Agricultural Burning - Prunings -Vineyard Removal (670-660-0262-9892)

County Crop Code Crop_Name

Activity

(tons) PM10 EF

PM10 EMS

(tons/day)

PM2.5/PM10

Fraction

PM2.5 EMS

(tons/day)

Fresno 614 Vineyard removal 46680 7.80 0.499 0.943 0.470 

Kern 614 Vineyard removal 6495 7.80 0.069 0.943 0.065 

Kings 614 Vineyard removal 495 7.80 0.005 0.943 0.005 

Madera 614 Vineyard removal 24630 7.80 0.263 0.943 0.248 

Merced 614 Vineyard removal 4410 7.80 0.047 0.943 0.044 

San Joaquin 614 Vineyard removal 6555 7.80 0.070 0.943 0.066 

Stanislaus 614 Vineyard removal 765 7.80 0.008 0.943 0.008 

Tulare 614 Vineyard removal 13935 7.80 0.149 0.943 0.140 

Total 1.05 

The recent 2012 activity data had not yet been provided at the time the Almanac was 

developed and published. Therefore, the Almanac’s 2012 estimates were forecasted 

from an earlier submittal for year 2009. These emissions were estimated from 2009 

burn activity using the same crop specific emission factors and methodology described 

above. Emissions were then forecasted from 2009 to 2012 using the change in total 

farm land acreage for each county from the California Department of Conservation 

Farmland Mapping and Monitoring Program (FMMP).

Table 8 shows the 2009 and 2012 farmland acreage totals used to generate a growth 

factor.
June 8, 2015

Table 8. Growth Factors from 2009 to 2012 Based on Total Farmland Acreage

County 2009 Acreage 2012 Acreage Growth Factor

Fresno 1,372,519 1,361,174 0.9917

Kern 926,650 896,212 0.9672

Kings 560,100 533,172 0.9519

Madera 362,150 359,280 0.9921

Merced 595,000 599,012 1.0067

San Joaquin 613,604 607,315 0.9898

Stanislaus 401,950 406,208 1.0106

Tulare 862,200 855,456 0.9922

Table 9 shows how 2012 emissions estimates in the Almanac were derived from 2009 

estimates using the growth factors derived above.

Table 9. Emission Projections from 2009 to 2012 used in the Almanac

Agricultural Burning - Prunings - Attrition

County 2009 Emissions Growth Factor 2012 Emissions

Fresno 0.03 0.9917 0.03

Kern 0.01 0.9672 0.01

Madera 0.02 0.9921 0.02

Merced 0.02 1.0067 0.02

San Joaquin 0.03 0.9898 0.03

Stanislaus 0.04 1.0106 0.04

Tulare 0.03 0.9922 0.03

Total 0.18

Agricultural Burning - Prunings - Grape Vines/Stumps

County 2009 Emissions Growth Factor 2012 Emissions

Fresno 0.13 0.9917 0.13

Kern 0.02 0.9672 0.02

Madera 0.03 0.9921 0.03

San Joaquin 0.01 0.9898 0.01

Tulare 0.01 0.9922 0.01

Total 0.19

Agricultural Burning - Prunings - Orchard Removal

County 2009 Emissions Growth Factor 2012 Emissions

Fresno 0.47 0.9917 0.47

Kern 0.10 0.9672 0.10

Kings 0.06 0.9519 0.06

Madera 0.06 0.9921 0.06

Merced 0.08 1.0067 0.08

San Joaquin 0.02 0.9898 0.02

Stanislaus 0.09 1.0106 0.09

Tulare 0.64 0.9922 0.64

Total 1.52

Agricultural Burning - Prunings - Tree Prunings

County 2009 Emissions Growth Factor 2012 Emissions

Fresno 0.07 0.9917 0.07

Kern 0.03 0.9672 0.03

Kings 0.01 0.9519 0.01

Madera 0.04 0.9921 0.04

Merced 0.10 1.0067 0.10

San Joaquin 0.10 0.9898 0.10
June 8, 2015

Stanislaus 0.10 1.0106 0.10

Tulare 0.03 0.9922 0.03

Total 0.46

Agricultural Burning - Prunings - Untreated Grape Stakes

County 2009 Emissions Growth Factor 2012 Emissions

Fresno 0.01 0.9917 0.01

Total 0.01

Agricultural Burning - Prunings - Vineyard Removal

County 2009 Emissions Growth Factor 2012 Emissions

Fresno 0.72 0.9917 0.72

Kern 0.31 0.9672 0.30

Kings 0.01 0.9519 0.01

Madera 0.24 0.9921 0.24

Merced 0.01 1.0067 0.01

San Joaquin 0.07 0.9898 0.07

Stanislaus 0.02 1.0106 0.02

Tulare 0.41 0.9922 0.40

Total 1.78

Agricultural Burning - Field Crops - Rice Stubble

County 2009 Emissions Growth Factor 2012 Emissions

Fresno 0.02 0.9917 0.02

Merced 0.04 1.0067 0.04

San Joaquin 0.03 0.9898 0.03

Stanislaus 0.02 1.0106 0.02

Total 0.10

Summary

Changes in the emission estimates between the Almanac 2013 and the 2015 San 

Joaquin Valley PM2.5 State Implementation Plan can be explained by recent changes

to the inventory. Some Managed Burning and Disposal categories in the 2015 PM2.5 

SIP have been updated to reflect more recent activity data. The Almanac is based on 

an older 2009 dataset which was forecasted to 2012.

Other differences are explained by the reclassification of Wildland Fire Use to the 

Natural Sources – Wildfires category. Emissions from WFU’s were still included under 

Managed Burning and Disposal when the Almanac was released, but appear under

Natural Sources in the 2015 PM2.5 SIP and subsequent inventories.

In all cases, the 2015 PM2.5 SIP uses the latest activity data available to estimate year 

2012 emissions. It provides our best estimate of the emission inventory for the San 

Joaquin Valley at this time.

Table 9 continued