Research article Can a GIS toolbox assess the environmental risk of oil spills? Implementation for oil facilities in harbors Paloma F. Valdor, Aina G. G  omez, Víctor Velarde, Araceli Puente * Environmental Hydraulics Institute “IH Cantabria”, Universidad de Cantabria, C/Isabel Torres N15, Parque Científico y Tecnol ogico de Cantabria, 39011 Santander, Spain article info Article history: Received 21 October 2015 Received in revised form 14 December 2015 Accepted 9 January 2016 Available online xxx Keywords: Oil spill Diffuse source Environmental risk analysis Affected areas Geographical Information System Tarragona harbor abstract 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 fa- cilities 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. © 2016 Elsevier Ltd. All rights reserved. 1. Introduction Environmental risk assessment (ERA) on aquatic systems has traditionally focused on point contaminant sources, but in coastal areas, diffuse sources are also an important introduction of pollu- tion (Preston, 2002; G omez, 2010). This fact is highly noted in port areas, where the water quality is a consequence of the uses and activities conducted in these environments (Darbra and Casal, 2004). Previous studies and records of contaminating events in port areas have noted that accidental spills are the main cause of water pollution, with a great proportion of oil spills in these areas occurring due to the loading and unloading of bulk liquid (Darbra and Casal, 2004; Peris e Mora et al., 2005). Many of the critical problems that arise in dealing with the pollution of aquatic systems by diffuse contaminant sources in port areas are inherently spatial issues. On many occasions, the inter- action of possible influences complicates the precise identification of surrounding hazards (stressors), their multiple effects, and consequently, the pathways to resolution (G omez et al., 2015). These interactions are more pronounced in port areas, where there Tool availability Name SPILL Tool Developer Environmental Hydraulics Institute of the University of Cantabria “IH Cantabria” Contact puentea@unican.es Year first available 2015 Hardware required ArcGIS 10.1 for Desktop system requirements Software required Python 2.4 or later; ArcGIS 10.1; FWTools (http://fwtools.maptools.org/) ArcGIS extensions required Spatial Analyst 10.1 ©1999 e2012 Esri Inc. Program languages Python Toolbox size 191 KB Availability: Download http://marport.ihcantabria.es/en/ descargas/ Cost Free * Corresponding author. Trueba Environmental Hydraulics Institute “IH Cantabria”, Universidad de Cantabria, C/ Isabel Torres Nº 15, Parque Científico y Tecnol ogico de Cantabria, 39011 Santander, Spain. E-mail addresses: fernandezvp@unican.es (P.F. Valdor), aina.gomez@unican.es (A.G. G omez), victor.velarde@unican.es (V. Velarde), puentea@unican.es (A. Puente). Contents lists available at ScienceDirect Journal of Environmental Management journal homepage: www.elsevier.com/locate/jenvman http://dx.doi.org/10.1016/j.jenvman.2016.01.012 0301-4797/© 2016 Elsevier Ltd. All rights reserved. Journal of Environmental Management 170 (2016) 105e115