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Air Dispersion Modeling

What are my facility's air quality impacts?

Air dispersion models are tools to assess impacts from air pollution sources. Why are these tools important? Air permit applicants must show that potential air quality impacts will not exceed specific health thresholds. If used before pollution sources are actually built, air dispersion models can be more advantageous than air monitoring.

What makes BlueScape stand out?

  • We have extensive experience using air dispersion modeling tools preferred by USEPA, state and local agencies for air quality impact evaluation.
  • We understand how to properly apply the models and recommend technical refinements to reduce calculated impacts.
  • We have solid working relationships with various agency staff that review dispersion modeling studies.
  • We use high-quality software and graphical tools such as ARCVIEW to provide clear, accurate visual representation of air quality impacts.

BlueScape will help you present a detailed, technical explanation of your project's air quality impacts to regulatory agencies and the public.

When your company must meet these regulation requirements:

  • Minor & major new source review air permitting
  • AB2588 "Toxics Hot Spots" regulation
  • California Proposition 65
  • CEQA & NEPA air quality impact studies
  • RCRA permitting and waste handling regulations

Turn To BlueScape...

We provide the necessary technical services:
  • Stationary source air quality impact calculations for criteria pollutants.
  • Health risk assessments for air toxic emissions from stationary sources.
  • Traffic studies: CO and NOx air quality impacts from mobile sources.
  • Meteorological data preprocessing for dispersion modeling.
  • Third-party review of air quality impact studies.
  • Good engineering design studies for proper stack ventilation.

We utilize various tools:


We help you to understand and communicate air quality impacts from your proposed project.

Sample Projects

Industry: Municipality; Wastewater Processing
Client: San Diego Metropolitan Wastewater District (SDMWD)
Prime Contractor: Montgomery Watson

Odor Modeling Study and Health Risk Assessment for Wet Weather Storage Facility in San Diego, California. Completed dispersion modeling study using the ISCST3 model to assess potential odor impacts and health risks. The San Diego MWD planned construction of a Wet Weather Storage Facility (WWSF), consisting of two 7 million gallon underground storage tanks, to handle future peak wastewater flows during storm events. Required analysis of potential nuisance odors and health risk impacts as compared to thresholds established by the San Diego APCD under Rule 1200 for surrounding businesses. Developed engineering design data, such as stack height, air flows, and scrubber control efficiency that would be required to meet City's odor design standards of 5 odor units (OU). Used conservative modeling and exposure assumptions, to show that odor impacts and health risks from the Wet Weather Storage Facility would meet design requirements.

Industry: Petroleum Industry
Client: THUMS, Inc.
Prime Contractor: Environmental Compliance Solutions

Modeling and Health Risk Assessment (HRA): New 44 MW Simple-Cycle Turbine in Long Beach, California. Owner of natural gas and petroleum production fields, planned to site a 44 MW simple-cycle turbine facility in Long Beach harbor to provide onsite electricity for well pumping. Needed modeling and HRA to show that operation was in compliance with South Coast Air District Rules 1303 and 1401. Modeled impacts from criteria pollutants (NOx, PM10, etc.), ammonia slip, and air toxics found at three candidate site locations. Examined the effect of different stack heights, and the effect of building downwash on air quality impacts. For each candidate site, determined a stack configuration that would result in compliance with the district rules.

Industry: Federal Facilities; Munitions Disposal
Client: U.S. EPA
Prime Contractor: Booz-Allen & Hamilton

Third-Party Modeling Review; Instantaneous and Short-Term Releases from Multiple Federal Munitions Disposal Facilities. Federal munitions disposal facilities located in West Virginia, Indiana and Pennsylvania proposed munitions disposal that involved open burning techniques. Health risk assessments were performed by the facilities following the USEPA Human Health Risk Assessment Procedures (HHRAP) guidance document. Models proposed for use included OBODM, ISCST3, INPUFF, and TRPUF. Resulting documentation required third-party review by an independent source. The review focused primarily on the appropriateness of modeling input data assumptions, including emissions, source release parameters, and meteorological data. Comments were provided to Booz-Allen, and submitted along with other comments to USEPA and state air pollution agency staff.

Industry: Metal Can ManufacturingClient: Confidential
Prime Contractor: Kleinfelder, Inc.

Stack Increase Study. Major beverage can manufacturing facility experienced possible entrainment of sulfuric acid emissions released from three stacks into building ventilation intakes, resulting in poor product finish quality for some can batches. Customers required plan of action to alleviate problem. Made visual observations at site and confirmed strong likelihood of a potential problem during strong northeast winds. Used ISCST3 model and ASHRAE ventilation guidance to estimate level of stack height increases required to avoid intake contamination. Study recommendations were used to begin reconstruction of stacks.