Air Quality Assessments

Air Quality and Greenhouse Gas Emission Assessments

Our air quality team specializes in the preparation of air quality and greenhouse gas assessments for a variety of projects, including mixed-use infill developments, transportation improvements, school expansions, solar power plants, and airport decarbonization plans.

We use air quality models (CalEEMod, EMFAC, AERMOD, HARP) to estimate air pollutant emissions, air pollutant concentrations, and health risks to nearby sensitive receptors. We also identify control measures to effectively reduce potential air quality impacts below threshold levels established by federal, state, and/or local agencies.

We closely follow the ever-changing regulatory scene of greenhouse gas emissions and provide comprehensive analyses to determine a project’s emissions and its consistency with regulations and planning goals. We also specialize in the preparation of project-level greenhouse gas inventories and reduction plans for large-scale projects.

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Freedom West 2.0 Project in San Francisco

Baseline Environmental Consulting prepared the Air Quality and Health Risk Assessment for the proposed Freedom West Project in San Francisco. The proposed project would demolish 22 existing buildings and construct 15 new buildings with 2,876,100 gross square feet of mixed-use development. Baseline evaluated and documented the following:

• Mass emissions of criteria air pollutants from construction, from combined construction and operational sources due to the overlapping development phases, and from operational sources at full buildout;

• Excess lifetime cancer risks and PM2.5 concentrations at sensitive receptors during construction and operation in addition to existing cancer risk and PM2.5 concentrations at sensitive receptor locations;

• Chronic hazard indices at sensitive receptors during construction and operation;

• Cumulative health risks including emissions from existing sources, the proposed project, and reasonably foreseeable future projects; and

• Available control measures based on quantitative and qualitative analysis that would reduce the proposed project’s criteria pollutant emissions and the project’s contribution to health risks.

GHG Analysis for OAK Airport Decarbonization Plan

Oakland Airport Terminal Decarbonization Plan

The Oakland San Francisco Bay Airport (OAK) Terminal Decarbonization & Audit 5-Year Implementation Plan (the Plan) outlines a comprehensive strategy to achieve significant reductions in greenhouse gas (GHG) emissions and energy consumption at the airport. The Plan was based on an evaluation of the energy and decarbonization measures for the period 2026-2030, aiming to achieve a 50% reduction in Scope 1 and 2 carbon emissions by 2030 compared to a 2019 baseline year in support of OAKs long term plans to be carbon neutral by 2040.

Baseline Environmental Consulting prepared a technical memorandum to evaluate the Scope 1 and Scope 2 GHG emissions associated with existing and forecasted energy consumption both with implementation of up to 33 energy efficiency and decarbonization measures. Examples of measures evaluated included expansion of rooftop photovoltaics, temperature zone sensors, and replacement of natural boilers with electric heat pumps.

Westside Aggregates Project in Colusa County

Baseline Environmental Consulting prepared the Air Quality, Greenhouse Gase, and Energy Analysis for the proposed Westside Aggregates Project in Colusa County. Westside Aggregates, Inc., is seeking entitlements to develop, operate, and reclaim an aggregate mining and processing operation in western Colusa County, approximately 4 miles west of the community of Arbuckle. Project operations would include excavation, onsite transporting of excavated materials via conveyors to a processing plant site, processing, washing and screening of mined materials, and transporting of processed materials offsite to regional construction projects. The project is seeking flexibility in annual exports to allow the proposed operation to accommodate variability in regional construction project demands and is therefore proposing maximum annual exports of up to 2,000,000 tons per year.

Based on project-specific information provided by the applicant, criteria air pollutant and GHG emissions were calculated using CalEEMod version 2022.1 methodology, CARB’s EMFAC2021 database, and the U.S. EPA’s Compilation of Air Pollutant Emissions Factors (AP-42) for the following sources:

• Off-road equipment exhaust and dust

• On-road vehicle exhaust and dust (tire and brake wear dust)

• Unpaved road dust (fugitive dust)

• Paved road dust (resuspended dust)

• Conveyor transporting and processing sand and gravel dust (fugitive dust)

• Stockpile erosion (fugitive dust)

• Groundwater supply well pump electricity use (GHGs)

• Conveyor transporting and Processing Plant electricity use (GHGs)

Based on project-specific information provided by the applicant, a health risk assessment was conducted using AERMOD and OEHHA guidance to evaluate the exposure of nearby sensitive receptors to diesel particulate matter during project operation for the following sources:

• Mining and Processing Plant off-road equipment exhaust (onsite)

• Haul truck running exhaust (onsite and along haul route)

• Haul truck idling exhaust (onsite)