EMISSION INVENTORY SOURCE CATEGORY

METHOD SUMMARY

This category includes 1993 estimates of fugitive dust particulate matter resulting from agricultural land preparation operations. These operations may include tilling, discing, ripping, land leveling, and other mechanical means of preparing the soil for planting.

ACTIVITY DATA SOURCE:  County-specific crop acreage is from the California Department of Food and Agriculture's compilation of harvested acreage. This data is developed from crop data submitted by county agricultural commissioners. Information about the type, quantity, and time of year that land preparation operations occur is predominantly from agricultural crop calendars developed with the assistance of agricultural experts. For crops where specific updated crop calendar data were not collected, the ARB's existing crop profiles were used.

EMISSION FACTOR SOURCE:  The emission factor used is from EPA's AP-42 document, Section 11.2.2 (4th Edition). California specific soil silt data were incorporated for the counties in the San Joaquin Valley. The remaining counties use the default 18% soil silt value recommended by EPA.

TEMPORAL DATA:  Land preparations are assumed to occur primarily during the day, seven days a week. The monthly activity profiles vary by county. They were derived by compiling the number of land preparations that occur during each month in each county. Refer to Appendix A for details on how the monthly profiles were developed. In addition, a correction was included to reduce tilling emissions during months of high precipitation. This was necessary because the current emission factor equation does not take soil moisture into account

DATE OF THE LAST UPDATE:  August 1997

GROWTH PARAMETER:  Growth based on agricultural crop acreage or agricultural production. Set to zero for many regions.

STATEWIDE EMISSIONS SUMMARY (1993 - ANNUAL AVERAGE TONS / DAY)

CES No.	TOG	CO	NOX	SOX	PM
47332	0.00	0.00	0.00	0.00	360.3

To download the complete methodology (94Kb) in Acrobat format, please click this icon;

Please send questions or comments to: eibweb@arb.ca.gov

This page last revised on November 12, 1997.

Area Source Top Page  |   Search ARB Programs / Topics  |   E-Mail ARB Help Attendant