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Land Use & CEQA

SLO County APCD Roles Under CEQA

1. The Lead Agency, as defined by CEQA, is the public agency that has the primary responsibility for carrying out or approving a project (State CEQA Guidelines Section 15367). To be a CEQA Lead Agency, the public agency must have discretionary authority over the proposed project. The Lead Agency also has the primary responsibility for determining what level of CEQA review is required for a project and for preparing and approving the appropriate document.

As a Lead Agency the SLO County APCD would prepare environmental documents for its own discretionary actions, such as air quality plans and rules, however the SLO County APCD rarely acts as a lead agency.

2. A Responsible Agency under CEQA is a public agency with some discretionary authority over a project or a portion of it, but which has not been designated the Lead Agency (State CEQA Guidelines Section 15381). Because Responsible Agencies will take discretionary actions regarding a project, they are also required to comply with CEQA. For efficiency, CEQA allows Responsible Agencies to rely on a CEQA document prepared by the Lead Agency to meet their CEQA compliance requirements. However, Responsible Agencies must independently review and approve the CEQA document, and not rely automatically on the Lead Agency’s judgments. According to CEQA, a Responsible Agency complies with CEQA “by considering the EIR or negative declaration prepared by the Lead Agency and by reaching its own conclusions on whether and how to approve the project involved” (State CEQA Guidelines Section 15096(a)).

The SLO County APCD is rarely a Responsible Agency and should seldom be named as a Responsible Agency in CEQA documents because the SLO County APCD does not usually independently review and approve CEQA documents.

3. As a Commenting Agency the SLO County APCD reviews projects that may have air quality impacts and evaluates whether the environmental document provides sufficient information and adequate mitigation to alleviate adverse impacts.

The SLO County APCD usually acts as a Commenting Agency. Comments are submitted to Lead Agencies for their consideration. However, the Lead Agency has the primary responsibility for determining what level of CEQA review is required for a project and for preparing and approving the appropriate document.

Calculating Construction Emissions for Project Level Review

There are a few SLO County APCD approved ways to calculate construction emissions for a given project. The first level of analysis for a project is to compare it to Table 1-1 in the SLO County APCD’s CEQA Air Quality Handbook. Although the intent of Table 1-1 is to screen a project’s size against operational threshold values, the SLO County APCD has calculated that if a project is under operational thresholds, the project will likely be under construction thresholds as well.

Note: The stated GHG Numerical Threshold column and its values are no longer valid. Projects should be compared to the ROG + NOx threshold column and values only.

If the project’s size exceeds the unit of measure listed, a more refined analysis of air quality impacts would be necessary. However, Table 1-1 screening is not applicable to:

  • mixed land use projects
  • projects with land uses that are not listed in Table 1-1
  • projects that involve heavy-duty diesel activity and/or fugitive dust emissions, such as soil remediation, road or infrastructure, and energy or extractive resource projects

For projects that require a more refined analysis, the next level of specificity in defining construction emissions involves the use of the most recent version of the California Emissions Estimator Model (CalEEMod). This model contains emission factors for a variety of construction equipment. It will automatically generate default values for various parameters. When modeling project emissions, the user must specify that the project is located in SLO County so that the appropriate default values are used for the modeling. If more detailed information about the construction phase of the project is known, the default values should be modified to more accurately reflect the anticipated emissions from the project. CalEEMod reports submitted as part of a CEQA evaluation need to include the following:

  • a winter, summer, and annual report
  • the model files associated with the reports
  • changes to any SLO County defaults need to be identified and a solid defensible explanation for those changes needs to be provided to the SLO County APCD

CalEEMod will not automatically calculate import or export off-site hauling trips and associated emissions. If soil or demolition materials will need to be hauled off-site or materials will be imported, cubic yards of material and the number of truck trips will need to be entered into the model. The trip length associated with hauling also needs to be entered into the model along with a detailed explanation of the trip length. Specific truck emission factors for the hauling fleet should be included in the simulation if known. If the specific fleet is unknown at time of modeling, then a defensible worst case set of hauling fleet emission factors shall be used. This hauling component is an important step and is often overlooked resulting in under estimation of emissions.


San Luis Obispo County APCD CEQA Tools

CEQA Handbook and Associated Tools: The California Environmental Quality Act (CEQA) was created to ensure that environmental impacts from new development are addressed and adequately mitigated. The District's CEQA Handbook provides information on the District's significance thresholds for determining potential air quality impacts from proposed residential and commercial development and provides recommendations on the level of mitigation necessary to reduce those impacts. Appendix A to the CEQA Handbook outlines the building permit requirements for facilities potentially subject to air district permitting. The CEQA Handbook was last updated on April 2012. The CEQA Handbook and tools listed below are intended to assist with CEQA reviews.

South County Air Quality Forecast Zone Map

CalEEMod Model: The California Emission Estimator Model (CalEEMod) is the emissions estimation model the District recommends using for landuse project. The model is free and available for download from the link below. The most recent verison of the model should be used.

Final GHG Threshold Supporting Documentation

California Air Pollution Control Officers Association (CAPCOA)

ARB's Air Quality and Land Use Handbook

ARB's Air Quality and Land Use Handbook: As part of the Air Resources Board's (ARB) Community Health Program, they have developed an Air Quality and Land Use Handbook (Handbook) which is intended to serve as a general reference guide for evaluating and reducing air pollution impacts associated with new projects that go through the land use decision-making process. More arrows.gif

ADAM Air Quality Data Statistics

ADAM Air Quality Data Statistics allows user to select and view air quality data for various pollutants throughout the State, including trend summaries, days above the standard, daily stats, 24-hour stats, etc.