Sullivan Environmental services

Sullivan Environmental staff dispersion modelers have over 30 years of experience each. This firm performs air dispersion modeling using the following computer models: AERMOD, CALPUFF 5.0, CALPUFF 6.0, CAL3QHC, INPUFF, ISCST3, TOXST, ISCPRIME, and SCREEN3. We utilize several different pre- and post-processing meteorological and source processing programs including PCRAMMET, BPIP, CALMET, CALPOST, SLAB, and others to support the modeling depending on the types of sources, meteorological datasets, and the specific project application(s). Sullivan Environmental has also developed various dispersion models such as TOXST, the Fumigant Emissions Modeling System (FEMS), and RISKMAN. The RISKMAN model was designed to assess emissions from dense gas facilities and accidental release scenarios. This model can be used to refine hazard zones for risk management programs (RMP).

Exposure assessment, risk assessment, and risk management are the three major components of assessing risks from exposure to air pollutants. The staff of Sullivan Environmental is in the forefront of developing methods for exposure assessment and conducts research for the U.S. EPA and industrial clients aimed at identifying exposures from specific source categories. Risk assessment involves the review of average and worst case exposures in relation to cancer potency scores relative to threshold limit values for non-cancer endpoints. Through identification of the upper-bound risks by pollutant and source category, the priority sources and pollutants for subsequent control analyses can be identified. Risk management involves evaluating the most cost-effective and practical ways to reduce risk (average exposures and maximum exposures). Sullivan Environmental Consulting has been involved in all of these areas with exposure assessment as the primary area of expertise.

Some firms have experience modeling individual industrial facilities to support permit applications. The true challenge for a modeler is to address the analysis on an urban-scale, model all quantifiable source categories in a metropolitan area, and determine how realistic the assessment is relative to measured air quality data.