EMISSION INVENTORY SOURCE CATEGORY

METHOD SUMMARY

These categories include 1997 estimates of total organic gas (TOG) emissions from gasoline cargo tanks. These emissions do not include the emissions from loading and unloading of gasoline cargo tank product; they are included in the gasoline terminal inventory and gasoline service station inventory. There are three emission points. Pressure-related fugitive emissions are volatile organic vapors leaking from fittings, valves and other connecting points in the vapor collection system on a cargo tank. Solar and reflective heat gains cause the vapor inside the cargo tank to expand and exert pressure to the tank walls, fittings and valves. Emissions from the product hoses are a result of residual product clinging to the walls of the hoses. Residual liquid, inside the hose, vaporizes into the ambient air resulting in emissions. Emissions from the vapor hose are a result of vapors trapped inside the hose after product delivery to the underground tank. Some vapors condense inside the hose. When the hose is disconnected from the underground tank and truck fittings, the vapors and condensed vapor inside the hose are emitted into the ambient air.

ACTIVITY DATA SOURCE: The total highway gasoline sales cited in the California Department of Transportation's report, "Travel and Related Factors in California" (1997), represents all gasoline transported by gasoline cargo tankers in California. The data in the report are used to derive each county's consumption of gasoline for the year 1997. Presently, gasoline delivery trucks or gasoline cargo tankers traverse the state delivering most of the 13.5 billion gallons of gasoline sold annually.

EMISSION FACTOR SOURCE: The emission factors are derived from the data in the report, "Emissions from Gasoline Cargo Tanks, First Edition," published June 2002.

TEMPORAL DATA: The temporal activity is uniform year round, with deliveries assumed to be continuous 24 hours per day, seven days per week and 52 weeks per year.

CHANGES IN METHOD AND EMISSION ESTIMATES: This is a new method.

DATE OF THE LAST UPDATE: June 2002

GROWTH PARAMETER: The growth parameters were developed by Pechan and are based on gasoline and oil expenditures data (in billions of 1992 dollars).


STATEWIDE EMISSIONS SUMMARY (1997 - ANNUAL AVERAGE TONS/DAY)

CES No.	TOG	CO	NOX	SOX	PM
89615	10.89	0.00	0.00	0.00	0.00
89623	0.44	0.00	0.00	0.00	0.00
89631	2.47	0.00	0.00	0.00	0.00
Total	13.80	0.00	0.00	0.00	0.00

To download the complete methodology (131Kb) in Acrobat format, please click this icon;

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

This page last revised on November 11, 2003

Area Source Top Page  |   Search ARB Programs/Topics  |   Email ARB Help Attendant