Simulation of potential formation of atmospheric pollution from aboveground storage tank leakage after severe storms

Abstract

Damage by severe storms of infrastructure containing chemicals can cause widespread pollution of the atmosphere and nearby bodies of water. Because atmospheric monitoring equipment is inoperable in the periods after these storms, transport and fate modeling approaches are necessary to estimate the regional atmospheric concentrations of evaporated spill material and secondary pollutants from such events. Hypothetical spills from a single storage tank in Houston were used to evaluate the impact of different meteorological scenarios (Hurricanes Harvey in 2017 and Ike in 2008), leaked materials (oils and organic solvents), background chemical conditions, and cloud conditions on simulated air pollution. Due to differences in evaporation rate, downwind oil plumes are predicted to cover a broader region than organic solvent plumes, which remain concentrated along the path of the prevailing wind. Depending on assumptions regarding evaporation, mixing ratios of spilled material of up to 90 parts per million are predicted. Substantial formation of ozone (up to an enhancement of 130 parts per billion) and secondary organic aerosol (up to an enhancement of 30 μg m−3) could occur in the short-term aftermath of these storms within the downwind solvent plumes, with the magnitude dependent on the solar radiation, type of material, and background pollutant level. This highlights the potential vulnerability of residents and workers in downwind regions to evaporated spill materials and their degradation products.