Monitoring emissions from a former Manufactured Gas Plant (MGP) site during remediation was used to manage risks associated with inhalation of Volatile Organic Compounds (VOCs) and contaminated particulates acting as an exposure conduit for Polycyclic Aromatic Hydrocarbons (PAHs) and heavy metals. This risk management case study presents a USEPA-approved air monitoring program implemented to manage public health risks during remediation at a former MGP site located in the southeast United States. Risk-based Acceptable Air Concentrations (AACs) were developed and a sampling regimen established to monitor potential emissions to maintain contaminant concentrations below the AACs. The exposure duration used was based on a twelve-month project duration and an exposure time of 24 hours per day; equations, toxicity values and sources were based on USEPA’s Regional Screening Levels. A total 535 twenty-four hour time weighted samples (269 VOC samples and 266 PAH samples) were collected over the project duration. Only minor levels of VOCs and PAHs were detected and no results were above the AACs. These timeweighted averages demonstrate that the real-time air monitoring and control measures implemented at the site effectively maintained concentrations below the AACs and were protective of public health.
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