RoseyFields conducted a comprehensive environmental evaluation and human health risk assessment for a large-scale petrochemical manufacturing facility following an unauthorized atmospheric release from an explosion at the facility. Our team evaluated the emission of hazardous air pollutants, specifically focusing on highly reactive volatile organic compounds and known human carcinogens such as ethylene oxide and ethyl chloride. The primary objective of this project was to assess the environmental fate and transport of these contaminants to determine the potential for acute and chronic human exposure in the surrounding community.
To accurately assess the extent of the chemical release, we performed in-depth air dispersion modeling and reviewed extensive ambient air monitoring data. Roseyfields utilized meteorological data, including wind speed and directional patterns, to simulate the atmospheric dispersion of both fugitive and point-source emissions over time. We thoroughly evaluated the inhalation exposure pathway by comparing modeled and monitored chemical concentrations at various downwind locations against established regulatory risk-based screening levels and reference toxicity values.
Based on the results of the environmental modeling and fate and transport analyses, RoseyFields successfully identified and characterized the potentially affected population. We mapped concentration isopleths to delineate the geographic boundaries of elevated chemical concentrations and overlaid this spatial data with local land-use and residential information. This approach allowed our team to accurately define the potential exposure class, characterizing varying levels of exposure risk for nearby residential, commercial, and sensitive receptors based on their proximity to the facility and the prevailing atmospheric conditions.
