Risk Characterization for Future Training Scenarios at the Massachusetts Military Reservation (MMR), Final Results

摘要

This study was conducted to evaluate potential human and ecological health risks associated with emission of pyrotechnic compounds during future training exercises at the Massachusetts Military Reservation. Air dispersion modeling was used to determine air concentrations and deposition rates for emissions. Annual average and spatially averaged air concentrations and deposition rates were used to perform the risk assessments. The Army Risk Assessment Modeling System (ARAMS) was used to conduct the human health risk assessment, which evaluated a site visitor or trespasser exposed to air and soil using air concentrations and deposition rates from the air dispersion modeling. ARAMS was also used to evaluate the time for deposited compounds to reach groundwater and the peak concentration upon contact with the water table. Of the 24 compounds evaluated, only Cr(VI), with an incremental cancer risk of 2.4 x 10(exp -6), posed a potential concern for human health with the maximum exposure and effect through the air inhalation pathway/route. None of the compounds are suspected to cause a groundwater problem. Computed soil concentrations were compared to soil screening toxicity benchmarks for the ecological risk assessment for the purpose of retaining or eliminating chemicals from the assessment. Toluene and hexachlorobenzene were the only compounds that exceeded the soil toxicity benchmarks. However, because of the slight exceedence and its nonbio-accumulating properties, toluene is not considered to be a chemical of potential concern. Although hexachlorobenzene exceeded the toxicity benchmark, uncertainties and conservative assumptions associated with the modeled soil concentrations and conservative soil benchmarks should be recognized.