SANTA BARBARA COUNTY AIR POLLUTION CONTROL DISTRICT

RULE 805 - AIR QUALITY IMPACT ANALYSIS AND MODELING
(Adopted 4/17/97)

A. Applicability

This rule shall apply to any new or modified stationary source where air quality impact analysis or modeling is required.

B. Exemptions

None.

C. Definitions

See Rules 102 and 801 for definitions.

"Excessive pollutant concentrations" means that concentration in excess of any applicable ambient air quality standard or increment.

"Effective Stack Height" means the height equal to the lesser of 1) 30 meters, or 2) H + 1.5 L, where H is the height of, and L is the lesser dimension (height or width) of, the source, or nearby structure, or, 3) such other height as is demonstrated to ensure that emissions do not result in excessive pollutant concentrations in the immediate vicinity of the source as a result of atmospheric downwash, eddies, or wakes which may be created by the source, nearby structures or terrain.

D. Requirements - General

1. Air Quality Models:

All air quality models shall be consistent with the requirements provided in the most recent "Guidelines on Air Quality Models" prepared by the Environmental Protection Agency unless the Control Officer finds that such a model is inappropriate for use. As of the adoption date of this rule, "Guideline on Air Quality Models," is 450/2-78-027R, July 1986. After making such finding, the Control Officer may designate an alternate model only after allowing for public comment and only with concurrence of the California Air Resources Board and the Environmental Protection Agency. District costs relating to modeling shall be reimbursed by the applicant pursuant to District cost reimbursement provisions.

2. Requirement - Effective Stack Height

For the purposes of determining effective stack height, the influence of a nearby structure is limited to five times its height or width, whichever is less, downwind. In meeting the requirements of this Rule pertaining to compliance with applicable ambient air quality standards or increments, the degree of emission limitation required shall not be affected by:

a. so much of the stack height of any source as exceeds good engineering practice or

b. any other dispersion technique.