A Tool For Comparing Relative Risks to Ecological Components Associated With Different Oil Spill Response Options

Abstract

ABSTRACT Subsea dispersant injection (SSDI) applied to a deepwater blowout has been shown to be a highly efficient oil spill response (OSR) tool that, under appropriate conditions, can substantially lessen and delay oil surfacing as well as reduce the persistence of surface oil slicks. Bock et al. (2018) explored the relative ecological and societal risks associated with integration of SSDI into OSR strategies in the northern Gulf of Mexico using a comparative risk assessment (CRA) desktop analysis tool. The CRA analysis tool was developed with regulatory and stakeholder engagement and communication in mind; the user interface and emphasis on visualization of the assessment results were intended to facilitate rapid examination of the consequences of different spill scenarios in the presence and absence of SSDI and other OSR technologies. Using the CRA tool, decision makers are now better able to predict the nature and extent of the likely consequences to shoreline and aquatic valued ecological components (VECs) and environmental compartments (ECs), and examine the relative consequences of deploying different response technologies. The CRA tool has been substantially improved and has been redesigned from an Excel spreadsheet into a web-based application with enhanced interactive data visualizations and collaboration tools. The new web-based CRA tool is based on the Shiny application framework, an R based open source system for building interactive web-based applications. The updated CRA tool (https://nert.shinyapps.io/CRA_viewer/) now includes improved visualizations of the oil spill modeling results, depictions of the spatial footprint of different ECs, and the interactive exploration of the CRA results and intermediate calculations. Stakeholders are able to drill down into the components of the analysis and more easily explore the parameters that drive CRA scores, as well as explore alternative scoring options. The tool has also been modified to facilitate updating the CRA tool for new oil spill scenarios and OSR options. This web-based interactive CRA tool greatly enhances the usability of CRA as a collaborative tool for evaluating OSR options during planning and can also be used to inform the evaluation of response options during planning, training, and during an incident.