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We describe the specifics of the BIOB numerical model, which can simulate the biodegradation of oil trapped in sand. The model simulates bacterial growth in the presence of nutrients and the subsequent consumption of hydrocarbons using Monod kinetics. The Exxon Valdez oil biodegradation in laboratory columns was simulated using the model. In order to explore oil bioremediation through natural attenuation and nutrient amendment, samples from Eleanor Island, Knight Island, and Smith Island were obtained and deposited in laboratory microcosms for a period of 168 days. Using a parameter estimation tool based on genetic algorithms, the kinetic parameters of the BIOB model were determined by fitting the experimental data (GA). While EL107 and KN114A's parameter values were comparable, SM006B's values were different from those of the other two sites. In particular, biomass growth on SM006B was four times slower than on the other two islands. The specific surface area per unit mass of sediment was much lower at SM006B, according to grain size analyses from each site, which suggests that the surface area of sediments is an important controlling factor for microbial development in sediments. Due to the lag period in microbial growth, BIOB was able to capture the early slow biodegradation in particular. According to sensitivity analysis, SM006B was sensitive to beginning biomass concentration because of its slow growth rate, whereas oil biodegradation at all three locations was sensitive to nutrient content. Additionally, analyses were done to compare the half-lives of various chemicals to the total number of Polycyclic Aromatic Hydrocarbons (PAHs).