Contents lists available at ScienceDirect Environmental Impact Assessment Review journal homepage: www.elsevier.com/locate/eiar Emissions from gas processing platforms to the atmosphere-case studies versus benchmarks David Broday a, ⁎ , Uri Dayan b , Einat Aharonov c , Dror Laufer d , Mike Adel d a Faculty of Civil and Environmental Engineering, Technion, Haifa, Israel b Department of Geography, The Hebrew University of Jerusalem, Israel c Institute of Earth Sciences, The Hebrew University of Jerusalem, Israel d Home Guardians, Israel ARTICLE INFO Keywords: Natural gas processing Environmental impact assessment Benzene and NMVOC emissions Cold vents Off-shore platform production ABSTRACT This study compares oil and gas industry benchmark non-methane volatile organic compounds emission data with predicted and reported emissions from a number of recent case studies. Specifically, we contrast predicted emissions from the Tamar and Leviathan processing platforms in the Eastern Mediterranean with actual emis- sions where available, and with a compilation of industry benchmarks. This work reveals a series of flaws in the adopted EIA practices in the case studies discussed, starting from the emissions model that grossly under- estimates intermittent NMVOC and benzene emissions relative to available data from other sites, and the un- realistic assumption of a constant and uniform emission profile in contrast to real world emission scenarios that are characterized by discrete large emission events. Furthermore, the dispersion model used in the EIAs as part of the request for a business (emissions) permit has a number of significant failings, including the use of an un- suitable model, use of over-simplistic meteorological inputs, and lack of consideration of critical dispersion phenomena. This study highlights the need to rethink the currently used environmental impact assessment and atmospheric permit request methodologies in the oil and gas industry, which rely on unrealistic uniform emission models. 1. Atmospheric emissions from offshore oil and gas installations worldwide Offshore oil and gas processing platforms, their mode of operation and their characteristic emissions vary widely in terms of chemical species, temporal profile and the emissions magnitudes. In order to predict atmospheric pollutant levels at coastal receptor locations due to emissions that emanate from offshore platforms, a credible emission model for the process train must be developed. A full analysis requires construction of a model that includes emissions characteristics of multiple scenarios, covering routine operation, maintenance, inter- mittent venting and catastrophic events. In this study, we focus on specific intermittent emissions and their environmental impact. One very common intermittent emission category, which occurs in both gas and oil processing platforms, is known as cold venting. This type of pollutant release involves mainly unburnt gases, which in the petro- chemical industry involves mostly organic matter. Here, we focus on non-methane volatile organic compounds (NMVOCs) and their specific carcinogenic indicator benzene, which forms a small proportion of the total NMVOC emissions. The logic behind the focus on these scenarios will be presented below. It is important to provide context in order to evaluate operator-predicted NMVOC emission levels versus some basic emission benchmarking data available from a number of regional and international benchmarking reports. Emission estimates are often based on self-reported data by the operator, whether based on continuous monitoring, emission factors or routine sampling. However, this practice has been questioned more and more frequently in a number of studies, which collected and analyzed mounting evidence that bottoms-up self-reporting systematically un- derestimates emissions compared with top-down operator-independent emission reporting (Petron et al., 2012). Furthermore, evidence has been presented to support the assertion that abnormal process condi- tions (e.g. malfunctions upstream of the point of emissions, equipment malfunctioning) may cause emissions responsible for the gap between component-based and site-based emissions. Such abnormal conditions can result substantial emissions to the atmosphere, resulting in what is termed “super-emitting sites” (Zavala-Araiza et al., 2017; Alvarez et al., 2018). This indicates a need for an independent “top-down” emission https://doi.org/10.1016/j.eiar.2019.106313 Received 6 March 2019; Received in revised form 1 August 2019; Accepted 8 September 2019 ⁎ Corresponding author. E-mail address: dbroday@technion.ac.il (D. Broday). Environmental Impact Assessment Review 80 (2020) 106313 0195-9255/ © 2019 Elsevier Inc. All rights reserved. T