Nearshore dredging for construction aggregate or beach nourishment can result in a perturbation of natural littoral processes, changes in wave transformation patterns, and a net loss of sand from the littoral system. A hybrid approach is developed which combines methods and results from both traditional Marine Geology and modern Computational Fluid Dynamics (CFD). The model has been successfully applied for solving the issues of environmental security in areas of the Black and Azov seas, where the underwater extraction of sand and gravel from the seabed took place. It has been shown that poorly arranged underwater quarry rejuvenate the coast and further development of the coast from young to old age causes terrible washouts in the coastal zone. Calculations performed on the hybrid model, were used to determine the width of the buffer zone for sand deposits. Above hybrid model also was used to obtain an insight on the tsunami hazard on coastal structures. A special interest is related to coastal areas with nuclear power plants (NPP) using ocean water for cooling the reactors. A hypothetical example of the application of the above approach to the events similar to the Fukushima Nuclear Power Plant Catastrophe is under consideration. As a tool for mitigation tsunami hazard on the NPP near shore facilities the method of the “Artificial Bay development” from the two triangle-shaped beach nourishments is proposed. The method provides that part of the tsunami destructive energy performs a useful work for both shore and facilities protection. Generation of tsunami waves by underwater disturbances is investigated.

tsunami, nuclear power plant, coastal area, wave propagation.