Sac Metro Air District recommends these tools and guidance documents to assist in air quality impact analysis. Additionally, thresholds of significance resolutions and justification documents are included.
Tools: Models, Calculators & Data Files
CalEEMod - NEWEST VERSION RELEASED JUNE 1, 2021
California Emissions Estimator Model including User's Guide (Sac Metro Air District recommends using CalEEMod Version 2020.4.0 for projects being released for public review after July 1, 2021).
Road Construction Emissions Model
Roadway Construction Emissions Model (version 9.0, May 2018). This is a .zip file. Please save it and then open it to extract the .xlsm file. IMPORTANT NOTE: U.S. EPA approved EMFAC2017 on August 15, 2019. Version 9.0 includes emissions factors from EMFAC2017.
The link to the Department of Conservation soil map website in the Data Entry tab of Version 9.0 is broken. Here's the updated link.
Version 9.0.1 (.xlsm file, August 2022) includes the updated link. No other changes to the model were made.
Version 8.1.0 included emissions factors from EMFAC2014 and was available for analysis of projects requiring federal involvement during the time period EMFAC2017 was being reviewed by U.S. EPA. Consult the Sac Metro Air District staff regarding the appropriate use of version 8.1.0 (version 8.1.0).
Harborcraft, Dredge and Barge Emission Factor Calculator
Harborcraft, Dredge and Barge Emission Factor Calculator for obtaining emission factors from marine equipment for planning and construction analysis (July 2017)
AERMOD Meteorological Data Files
Sac Metro Air District provides two sets of AERMOD meteorological data files (2014-2018) (These are .zip files. Please save the files and then open them to extract the PFL and SFC files):
Guidance: Protocols, Recommendations & Other Documents
Recommended Mitigation Measures
Link to Sac Metro Air District's recommended mitigation measures for construction and operational emissions, including the Recommended Guidance for Land Use Emission Reductions (AQMP guidance).
Cool pavement strategies to reduce Urban Heat Island impacts (December 2020).
Friant Guidance
The Guidance to Address the Friant Ranch Ruling for CEQA Projects in the Sac Metro Air District (October 2020) provides screening health information for projects at or below regional CEQA thresholds of significance emissions levels and selected strategic areas above thresholds of significance emissions levels. Modeling guidance for large projects located outside strategic areas is also included.
Friant Guidance Archive files:
Mobile Sources Air Toxics Protocol
Mobile Sources Air Toxics Protocol for assessing potential cancer risk to receptors located near major roadways and railways (September 2020) including supporting document on landscape barriers:
Existing Sources of Odors and Toxic Air Contaminants
Recommendations for Siting New Projects Near Existing Sources that Emit Odors and Toxic Air Contaminants (July 2019) for addressing potential public health impacts for projects that may expose receptors to existing sources of odors and toxic emissions.
Other Helpful Resources
General Rules Statement for Development Projects (October 2020)
State CEQA Guidelines Appendix G (June 2019, courtesy of AEP)
Sacramento Area Council of Government (SACOG) Regional Plans
Folsom Landfill Clean Closure Work Plan (May 2008) - example air monitoring plan, Appendix E
CAPCOA Roadway Review Guidance
In August 2018 the California Air Pollution Control Officers Association (CAPCOA) published Air Quality Analysis in CEQA Roadway Review to address frequently questioned topics in air quality analysis, including greenhouse gases, for roadway projects reviewed under CEQA. The guidance is intended for use by lead agencies in preparing air quality analysis and by air districts in reviewing and commenting on roadway project CEQA documents. Please note that this is not comprehensive
guidance on air quality analysis for CEQA review of roadway projects. It only
responds to common questions and current misconceptions. Air districts often
have guidance on a full range of topics in CEQA air quality analysis, which is
appropriate for overall air quality analysis in their geographic area. Please
consult any of the Sac Metro Air District staff listed below to determine the
appropriate methodology for project specific CEQA analysis.
Adopted Thresholds of Significance Resolutions and Documentation
Notice of Thresholds Adoption March 2002
Resolution adopted October 2014 for Greenhouse Gases
Resolution adopted May 2015 for Particulate Matter
Resolution adopted April 2020 for Updated Operational Land Development Greenhouse Gases
Greenhouse Gas Thresholds for Sacramento County, released March 4, 2020, adopted April 23, 2020, and report finalized June 1, 2020, with minor changes (removed DRAFT, updated needed website links, reported the City of Galt adopted a climate action plan on March 4, 2020, and corrected use of the term offset when referencing mitigate)
