Recently the development of industrial complex site to support the local manufacturing industries and clusters is so active by reengineering and expanding the existing sites or reclaiming the coastal zone. Therefore, it is necessary to analyze the impact of the coastal reclamation work in terms of physical and environmental characteristics. This study is dealing with the impact of coastal reclamation work in terms of working phase. The change of sedimentation and diffusion system under the action of winds, waves and current are discussed and the analysis of the field measurement and comparison with the numerical simulation are followed. The site for application in this study is at the coastal boundary near Onsan national industrial complex, Ulsan metro city. In order to verify the numerical simulation result, it is compared to the collected data for tide, current, and sediments of the existing measurement and field observation at the selected stations for this study. The verified numerical models were applied to the actual field by construction step and the future change was analyzed.