AIR EMISSIONS REGULATIONS:

Air Quality Status	Whole area in attainment (The AQMD is all of Tehama County) EPA's Nonattainment Areas
Major Source Threshold	250 tons of a criteria pollutant
Minor Source Permitting Exemption	Available based on size, hourly operation or type of use
Minor Source Treatment	BACT
Emergency Generating Limits	Determined by air district

DE MINIMIS EXEMPTIONS (Must meet 1298)

Source must apply for an exemption and none is guaranteed. However, most units smaller than 50 hp and burning natural gas, gasoline or diesel as well as those used for agriculture operations, fire fighting, lab research or flood control will be exempted. Units that operate less than 200 hours per year, turbines less than 0.3 MW or less than 4 MW with operation limited to 877 hours per year are also likely to be exempted.

MINOR SOURCE PERMITTING

The air district follows CARB's guidance for permitting of electric generating technologies. This guidance recommends BACT for all criteria pollutants. Sample BACT for control of NOx from turbines and internal combustion engines is as follows:

Size of Unit	Level of Control (ppm)
>3 MW	9
3-12 MW simple cycle	2.5
3-12 MW combined cycle	5
12-50 MW simple cycle	2.5
12-50 MW combined cycle	5
IC Engines	9

Additional limitations may be required by the air district based on any health risks imposed by the project.

TREATMENT OF EMERGENCY ENGINES

Emergency engines can be exempted by the air district. Units must apply and a determination will be made. Generally units may only operate during emergencies. Any additional requirements will be determined based on the health impact of the unit. CARB Air Toxic Control Measures for Stationary Compression Engines apply (see the CA state page for more information).