In contrast to the 222,000 acres burned in fall 1988 (about half the rice acreage), only 130,000 acres were burned last fall. September storms put rice harvest behind schedule and subsequent dry, stagnant air during the remainder of autumn stretched the burning season out through November 27. Another 30,000 acres were burned in December during the winter phase of the program.

Partially because of the reduced acreage, the Air Resources Board recorded only four complaints last year, the fewest on record. The stagnant fall air also explains why basin-wide haze remained about the same as in 1988, even though fewer acres were burned.

Prior to the beginning of the burning season on September 15, a new, more powerful radio was installed atop the Sutter Buttes to repeat meteorological information transmitted from automated monitoring sites scattered throughout the valley.

The new radio performed well throughout the fall burn, with one radio interference problem noted at the beginning of the season.

Last fall also marked the implementation of a new, computerized wind-model, which assisted county officials in the burning program and also in forecasting winds for aerial applicators who work in the rice industry. A high-resolution geographic database incorporated with graphic display software enabled meteorologists to generate wind pattern charts and fax them to central computer operators. The wind model garnered high marks from Weather Network, Inc., the company that contracted with the Rice Research Board to implement it.

Burning management zones were also revised in 1989 to help optimize the acres burned in the Valley while not affecting populated areas. The day that generated the most complaints was also the day when the most burning took place-16,349 acres on October 20.

Although agricultural burning contributes to air pollution, emissions from other sources, particularly motor vehicles, contribute significantly to the problem (see table). Nonetheless, environmental and health concerns continue to play a major role in the Sacramento Valley Burning Management Program.

The Sacramento Valley Air Basin Control Council is proposing a new agricultural burning fee for growers of other crops who benefit from the program without sharing in its cost. The fee structure had not been determined as this report was written.

The agricultural burning management program has improved the air quality in the Sacramento Valley, protected urban areas from smoke impacts, and maintained burning as a tool in agricultural operations. These achievements can be attributed to the efforts of the last nine years during the fall burning management program. The program elements that have provided most benefit have been variable acreage allocations, valleywide distribution of burning, shortened burn hours, availability of current air quality, meteorological, and burn data for decision-making, use of computers to store, transmit, and analyze data, and flexible program policies and procedures.

 

Sacramento Valley Air Emissions
	Emissions (Tons/day)
Source	TOG	NOX	CO	PM
Agricultural burning	18.78	0.0	146.19	16.25
Motor vehicles	113.42	131.71	879.05	19.41
Fuel combustion	13.02	19.45	49.03	6.32
Solvent uses	55.83	0.0	0.0	0.01
Petroleum processes	51.98	4.79	0.64	0.38
Industrial processes	5.95	2.39	1.83	19.83
Misc. processes	54.85	5.88	382.41	783.23
TOG = total organic gases		CO = carbon monoxide
NOX = nitrogen oxides		PM = particulate matter
Although agricultural burning contributes to the air pollution in the Sacramento Valley, there are emissions from many other sources in the Valley, especially motor vehicles. This table compared the emissions of an average day during 1987.