DETERMINING ENVIRONMENTAL PROTECTION 

 PRIORITIES IN COASTAL ECOSYSTEMS 



Erich R. Gundlach, Miles O. Hayes, and Charles D. Getter 



Research Planning Institute, Inc. 



Columbia, South Carolina 



INTRODUCTION 



It is well known that the vast majority of United States oil spill inci- 

 dents occur within coastal waters (73.7 percent in 1976) (USCG 1977). In 

 order to adequately plan an operation to deal with a large oil spill, and to 

 present the On-Scene Coordinator (OSC) and Scientific Support Coordinator (SSC) 

 with the fullest range of options, the potential impact area must be character- 

 ized simply and systematically for probable spill damage before the spill 

 occurs. For this purpose, an oil spill vulnerability index has been developed 

 after an extensive literature search and personal investigation of three mass- 

 ive oil spills [Metula, Vrquiola, and Amoco Cadiz) and several smaller inci- 

 dents (including spills under tropical and ice conditions). A list of major 

 spill studies that were used to determine oil impact on various coastal envi- 

 ronments is presented in Table 1. 



THE OIL SPILL VULNERABILITY INDEX 



Coastline environments are classified on a scale of 1 to 10 in terms of 

 potential vulnerability to oil spill damage. The index is based primarily on 

 the residence time or persistence of spilled oil within each environment, al- 

 though initial biological impact is considered. The persistence of oil is 

 determined primarily by physical processes (waves, tides, and when present, 

 ice movements) (Gundlach, et al . 1978, Owens 1978). 



The vulnerability index is summarized below; details are presented in 

 Gundlach and Hayes (1978b). Environments are presented in order of increasing 

 vulnerability to oil spill damage. 



Exposed, Steeply Dipping or Cliffed Rocky Headlands 



Based on observations during the Urquiola and Amoco Cadiz oil spills, oil 

 was generally kept 5 to 10 m offshore by waves reflecting off the steep rocky 

 coast. Damage was minimal and oil that did strike the coast was rapidly re- 

 moved by wave activity. 



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