Development of a practical methodology for integrating shoreline oil-holding capacity into spill modeling

Oil spill trajectory, fate, and risk modeling requires an understanding of the interactions of spilled oil with sediments on beaches. To most accurately simulate the movement of oil, the model needs to simulate the behavior of the spilled oil as it contacts a shoreline and either strands on and/or penetrates into the sediment or refloats to be deposited elsewhere. In particular, it is necessary to incorporate an estimate of shoreline oil retention into the algorithms of these models in the sediments of shorelines. A literature review of relevant shoreline oiling studies was conducted. The relevance of study findings for inclusion in modeling was considered. In addition, detailed shoreline cleanup assessment team (SCAT) survey data from a number of well-documented spills were analyzed for patterns in oil penetration and oil-holding capacity by shoreline sediment type and oil type for potential application in modeling algorithms. A relatively simple and practical method to estimate the oil-holding capacity of shoreline sediments based on shoreline type and oil properties was derived from empirical SCAT data and a theoretical beach hydraulics model for application in a stochastic spill model. Information gaps were identified and recommendations for potential future studies were outlined.