Modeling atmospheric volatile organic compound concentrations resulting from a deepwater oil well blowout – Mitigation by subsea dispersant injection. (November 2018)

• Record Type: Journal Article
• Authors: Crowley, Deborah; French-McCay, Deborah; Santos, Lynne; Chowdhury, Biswanath; Markussen, Robin
• Is Part Of: Marine pollution bulletin. Volume 136(2018)
• Page Start: 152
• Page End: 163
• Publication Date: 2018-11
• Subjects: Oil spill response -- Atmospheric exposure -- Oil fate modeling -- Deepwater oil spill -- Air pollution -- Health Safety and Environment (HSE); Marine pollution -- Periodicals; Marine Biology -- Periodicals; Water Pollution -- Periodicals; Mer -- Pollution -- Périodiques; Publications périodiques; Pollution des mers; Lutte antipollution; Electronic journals; 363.7394
• DOI: 10.1016/j.marpolbul.2018.09.001
• Languages: English
• ISSNs: 0025-326X

Abstract

Abstract: The atmospheric concentrations of volatile organic compounds (VOCs) generated by surface slicks during an oil spill have not been extensively studied. We modeled oil transport and fate, air emissions, and atmospheric dispersion of VOCs from a hypothetical deepwater well blowout in De Soto Canyon of the Gulf of Mexico assuming no intervention and use of SubSea Dispersant Injection (SSDI) at the source during three week-long periods representing different atmospheric mixing conditions. Spatially varying time histories of atmospheric VOCs within ~2 km from the release site were estimated. As compared to the no-intervention case, SSDI dispersed the discharged oil over a larger water volume at depth and enhanced VOC dissolution and biodegradation, thereby reducing both the total mass of VOCs released to the atmosphere and the concentration of VOCs within 2 km from the release site. Atmospheric conditions also influenced the VOC concentrations, although to a lesser degree than SSDI. Highlights: VOC flux to the atmosphere from a deepwater blowout was modeled. Alternative response scenarios with and without dispersant injection were compared. SSDI substantially reduced predicted atmospheric concentrations of VOCs. Evaporative flux varied greatly between untreated and treated-with-SSDI scenarios. Evaporative flux varied slightly between different meteorological conditions.