A Review of Response Options to Accelerate the Recovery of Oiled Shorelines

Abstract

The rate at which oil on shorelines weathers and attenuates is a function of the character of the oil on the shoreline (type and volume), the character of the shoreline materials, and the environmental setting (physical and biological). Some light crude oils or products have a very short half-life and may persist for only hours or days whereas other oils may persist for months to years. The objective of this review is to summarize how and why the different commonly used and available response options can contribute to accelerating shoreline recovery and to explain the potential consequences of these actions. Globally, the most widely used shoreline treatment activity is simple physical removal by manual or mechanical cleanup methods with off-site disposal. The explanation for this situation lies in the fact that this method is typically quick, easy, and requires no special skill sets or dedicated equipment. The second most widely used treatment method is low-pressure flushing or washing. A concern with this option is that typically little or no oil is recovered, unless the oil loading on the shore is very high and, although some of the oil may be broken down and dispersed in the water column and then biodegraded, if the method generates oil residue-sediment aggregates these may be negatively buoyant when the sediments are granular (> 1 mm) or coarser. Many guides and manuals describe the mechanics and implementation of these and other treatment methods; this review evaluates the state-of-the art with respect to currently available and widely applicable treatment options to accelerate oiled shore- line recovery. This knowledge is intended to support the creation of a science-based Shoreline Response Program (SRP) Decision Support Tool that is under development as part the Fisheries and Oceans Canada Multi-Partner Research Initiative (MPRI) program. The primary benefit of this tool is to enhance the quality of strategic planning regarding shoreline response intervention and non-intervention decisions related, in part, to Alternative Response Technologies for shoreline treatment.