Horizon provides air quality and greenhouse gas (GHG) assessments that are required for CEQA/NEPA compliance and environmental permitting. We have substantial experience with commonly used emission inventory models, including California Emission Estimator Model (CalEEMod), OFFROAD, EMFAC, and the Sacramento Air District’s Road Construction Model. Horizon’s services include conducting GHG assessments for individual projects and general and specific plans.

For CEQA/NEPA projects, Horizon’s air quality specialists:

• Identify and quantify project-specific construction and operational air quality pollutants/GHG emissions;
• Consider appropriate local and federal significance thresholds and existing air basin quality conditions;
• Perform appropriate analyses based on project type and/or federal nexus (i.e., general or transportation-related conformity analyses for projects with a federal nexus); and
• Develop successful mitigation strategies for air quality and climate change improvement that meet the needs of the client, community, and regulating agencies.

Additionally, Horizon works closely with clients to address energy resources effects and climate change-related adaptation considerations, such as sea level rise and flooding risks, changing water supply conditions, and/or increased wildfire risks.