In this paper, we discuss an issue of underwater mining and why modern mining equipment does not fit this purpose. Working in such complicated conditions often has an unsatisfying performance level. We analyzed the processes of mining materials that have not been preliminary dewatered. We also describe variations of positioning system and the importance of their use in underwater mining. A theoretical analysis of excavation process with a perforated bucket has been performed. We present a formula that allows assessing extent of bucket loading by parameters of the working face development. Another formula that allows determining the number of excavation cycles required to complete the bucket loading. A formula for parametric length of working face arc determining by the given stratum depth was introduced. Basing on the acquired formulae, we formulated another one that determines the number of excavation cycles necessary for complete face development for specified cutting parameters. An aggregated graph showing the dependency of the number of excavation cycles on peat shavings width and thickness variables. On the basis of the resulting graph, the best variant for the most complete bucket loading was chosen. In conclusion, we highlighted the peculiarities of underwater mining.