Atmospheric Dispersion Modeling
Advanced air dispersion modeling services that predict how pollutants spread through the atmosphere, enabling informed decisions for permit applications, compliance demonstrations, facility design, and community health protection. We deliver scientifically rigorous modeling that meets regulatory standards while providing actionable insights for air quality management.
Predictive Air Quality Science
Atmospheric dispersion modeling is the cornerstone of modern air quality management, providing scientifically defensible predictions of how pollutants transport and disperse in the atmosphere. These sophisticated mathematical models simulate the complex interactions between emission sources, meteorological conditions, terrain features, and atmospheric chemistry to forecast pollutant concentrations at receptor locations. Whether you're seeking an air quality permit, evaluating facility modifications, assessing community health impacts, or demonstrating regulatory compliance, accurate dispersion modeling is essential for making informed decisions and protecting public health.
Henddu's atmospheric dispersion modeling team brings extensive experience with EPA-approved regulatory models including AERMOD, CALPUFF, AERSCREEN, and specialized tools for specific applications. We combine rigorous technical expertise with practical knowledge of regulatory requirements across federal, state, and local jurisdictions. Our modeling studies are designed not just to meet compliance requirements, but to provide actionable insights that support strategic decision-making, facility design optimization, and stakeholder communication. From simple screening analyses to complex multi-source, multi-pollutant assessments with chemical transformation and deposition, we deliver modeling solutions tailored to your project needs and regulatory context.
Our Modeling Capabilities
Regulatory Modeling (AERMOD)
EPA-approved AERMOD modeling for Prevention of Significant Deterioration (PSD), Title V permits, and state air quality permit applications with complete documentation.
Long-Range Transport (CALPUFF)
CALPUFF modeling for Class I area impacts, visibility analysis, regional-scale transport, and multi-source, multi-pollutant assessments with complex terrain.
Screening Assessments
Rapid screening analyses using AERSCREEN for preliminary impact evaluations, significant emission rate determinations, and project feasibility assessments.
Health Risk Assessment Support
Dispersion modeling integrated with health risk assessment frameworks for toxic air pollutants, cancer risk evaluation, and community exposure analysis.
Stack Height & Design Analysis
Good Engineering Practice (GEP) stack height analysis, optimization studies, and dispersion modeling to support facility design and emission control strategies.
Specialized Applications
Odor dispersion modeling, visibility impact analysis, deposition studies, building downwash assessment, and emergency response planning for accidental releases.
Value of Professional Dispersion Modeling
- Secure air quality permits faster with defensible, agency-accepted modeling analyses
- Demonstrate regulatory compliance with National Ambient Air Quality Standards (NAAQS) and Prevention of Significant Deterioration (PSD) increments
- Optimize facility design and emission control strategies before construction, reducing capital costs
- Evaluate multiple operational scenarios and control options to identify cost-effective air quality solutions
- Assess potential community impacts proactively, supporting stakeholder engagement and social license to operate
- Support due diligence for facility acquisitions, expansions, or modifications with air quality impact assessments
- Respond effectively to regulatory inquiries, public concerns, or enforcement actions with sound technical documentation
- Integrate modeling results with health risk assessments for comprehensive environmental impact evaluation
Our Modeling Approach
Project Scoping & Model Selection
We begin by understanding your project objectives, regulatory context, and technical requirements to determine the appropriate modeling approach, tools (AERMOD, CALPUFF, AERSCREEN), and level of analysis needed for your specific application.
Data Collection & Quality Assurance
Systematic gathering of model inputs including source characterization (emission rates, stack parameters, exit conditions), meteorological data from representative monitoring stations, terrain elevation from USGS databases, land use classifications, and receptor locations based on regulatory requirements and site-specific considerations.
Model Development & Execution
Configuration and execution of dispersion models using EPA-approved versions and methodologies. Quality assurance reviews verify proper model setup, appropriate options selection, and correct processing of meteorological data and terrain information before production runs.
Results Analysis & Interpretation
Comprehensive analysis of model outputs including maximum concentrations, spatial distribution of impacts, temporal patterns, and comparison to applicable air quality standards and screening thresholds. Development of concentration contour maps, time-series plots, and statistical summaries.
Documentation & Regulatory Submittal
Preparation of comprehensive modeling reports documenting methodology, input data, assumptions, quality assurance procedures, results, and conclusions. Reports formatted to meet specific regulatory requirements including detailed appendices with model input/output files for agency review.
Get Expert Dispersion Modeling
Partner with Henddu's experienced modeling team for scientifically rigorous, regulatory-compliant dispersion modeling that supports your air quality objectives.
Request Modeling Consultation