Can a GIS toolbox assess the environmental risk of oil spills? Implementation for oil facilities in harbors

Oil spills are one of the most widespread problems in port areas (loading/unloading of bulk liquid, fuel supply). Specific environmental risk analysis procedures for diffuse oil sources that are based on the evolution of oil in the marine environment are needed. Diffuse sources such as oil spills usually present a lack of information, which makes the use of numerical models an arduous and occasionally impossible task. For that reason, a tool that can assess the risk of oil spills in near-shore areas by using Geographical Information System (GIS) is presented. The SPILL Tool provides immediate results by automating the process without miscalculation errors. The tool was developed using the Python and ArcGIS scripting library to build a non-ambiguous geoprocessing workflow. The SPILL Tool was implemented for oil facilities at Tarragona Harbor (NE Spain) and validated showing a satisfactory correspondence (around 0.60 RSR error index) with the results obtained using a 2D calibrated oil transport numerical model. [Display omitted] •Spills related to diffuse oil sources are a widespread problem in port areas.•A GIS tool to assess the environmental risk for diffuse oil sources is presented.•The SPILL Tool provides probabilistic potential affected areas for specific scenarios.•The SPILL Tool is applied to a wide range of scenarios at Tarragona.•The SPILL Tool satisfactorily reproduces the results of a calibrated numerical model.