AIR EMISSIONS REGULATIONS:

Air Quality Status	In attainment (The AQMD is all of Shasta County) EPA's Nonattainment Areas
Major Source Threshold	250 tons of any criteria pollutant
Minor Source Permitting Exemption	50 hp or 200 hours per year
Minor Source Treatment	BACT
Emergency Generating Limits	200 hours per year

DE MINIMIS EXEMPTIONS (Must meet 1298)

Sources less than 50 hp or operating fewer than 200 hour per year are exempt from permitting.

MINOR SOURCE PERMITTING

The air district follows CARB's guidancefor 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. The permitting process takes about 60 days and no comment period is required for minor sources.

TREATMENT OF EMERGENCY ENGINES

Emergency engines must be permitted and will receive a limit of 200 hours per year, but do not have to meet BACT. These units may only operate during emergencies and for maintenance. CARB Air Toxic Control Measures for Stationary Compression Engines apply (see the CA state page for more information).