The Cleaning of Gravel Beaches Polluted by Oil

An attempt to clean beaches without the use of dispersants was undertaken in Chedabucto Bay, Nova Scotia, following a spill of Bunker C oil from the tanker "Arrow" in the spring of 1970. Sand beaches account for less than 2% of the coast of Chedabucto Bay and those which were polluted were cleaned manually using peat moss, rakes, and shovels. Most sand beaches can be cleaned with relative ease, as oil does not permeate the sediments, and the angle of sand beaches is generally low so that mechanical methods can be applied without large-scale removal of beach sediments. Oil deposited on gravel beaches permeates below the surface layer and cleaning by mechanical methods involves excavation of beach sediments to depths of one metre or more. This method endangers the stability of a beach, particularly if the sediment supply is limited. Also this method was found to be ineffective in removing all contaminated sediments.