Optimal nutrient application strategy for the bioremediation of oil-polluted beaches

Bioremediation of oil polluted beaches commonly requires the application of nutrients that enhance microbial growth and biodegradation of oil. An effective strategy for application is one that maximizes the residence time of nutrients in the bioremediation zone while minimizing the cost. We propose herein a strategy that consists of applying the nutrients at the high tide line through a perforated pipe, and we computed the flow (and volume of solution). The results were generalized to various beach slopes (varying from 36 % to 3%) and to various tidal range and periods using a novel formulation for solute transport in porous media (the beach sand). The generalized results are presented in forms of nomographs that allow one obtaining the optimal nutrient flow rates by directly inputting the beach slope, permeability, and the tidal amplitude and period.