Air Quality Assessment for CEQA

CEQA provides governmental decision-makers and the public with information about the potential significant environmental effects of proposed projects.

It applies to all discretionary activities proposed to be approved by California public agencies unless an exemption applies. When a public official in a governmental agency has the ability to make a decision based on factors beyond simple compliance with rules or regulations, it is a discretionary project. If the public official merely applies the law to the facts as presented but uses little or no personal judgment, the project is ministerial and exempt from CEQA.

The goals of CEQA are for California’s public agencies to identify the significant environmental effects of a project's actions and either avoid or mitigate them where feasible if found significant. By identifying and discussing all significant impacts, CEQA:

• Allows the project applicant to change the project to mitigate adverse effects
• Provides lead agencies with the information necessary to impose conditions on the project to mitigate adverse effects
• Gives the public access to information about the effects of projects
• Provides policy boards with important information for determining whether the project “protects the public health, safety and welfare”

The CEQA Statute and Guidelines are available for download on the Association of Environmental Professionals website.

As a result of revisions to the CEQA Guidelines in 2010, lead agencies are obligated to determine whether a project’s greenhouse gas emissions significantly affect the environment and impose feasible mitigation to eliminate or substantially lessen any such effects. Guidelines can be found in the Handbook for Analyzing Greenhouse Gas Emission Reductions, Assessing Climate Vulnerabilities, and Advancing Health and Equity produced by the California Air Pollution Control Officers Association.

The Ventura County Air Quality Assessment Guidelines (AQAG) is an advisory document prepared by the VCAPCD that provides lead agencies, consultants and project applicants with a framework and uniform methods for preparing air quality impact assessments and the air quality section of environmental documents for projects that require discretionary entitlements. Pursuant to CEQA, the AQAG recommend specific criteria and threshold levels for determining whether a proposed project may have a significant adverse air quality impact. The guidelines also provide measures that may be useful for mitigating the air quality impacts of proposed projects. It is important to consult with VCAPCD staff on recently prepared projects as some of the guidelines in the AQAG are outdated and newer mitigation measures have been in practice for both emission reduction of construction activities and mitigation of project operational emissions.

The California Emissions Estimator Model (CalEEMod), which was first released in 2011, calculates criteria pollutant and greenhouse gas emissions from a variety of land uses, including residential and commercial projects. A more accurate estimate of project emissions can be accomplished by modifying the default settings for a given land use selected with project-specific traffic information, construction equipment and schedule information, and other major sources of emissions such as utilities (electricity, natural gas, etc.) proposed.

The model quantifies direct emissions from construction and operation, including vehicle use, as well as indirect emissions such as energy use, solid waste disposal, vegetation planting and/or removal, and water use. It also identifies mitigation measures to reduce criteria pollutant and greenhouse gas emissions and calculates the benefits achieved from measures chosen by the user. We recommend using CalEEMod instead of older emission model applications, including URBan EMISsions or URBEMIS, for estimating emissions from proposed land use development projects.