The article presents results of field studies at a site of radioactive waste storage and disposal facilities (the so-called LD RosRAO site, Sosnovy Bor, Leningrad region, Russia). The objective of the study is to overview the history and occurrence of groundwater contamination to answer the question whether the radioactive plume is historical (formed due to accidents, which happened at the beginning of the operations with the radioactive waste) or the release of radioactive solutions to groundwater is still occurring. The main method used to study the evolution of radioactive contamination is to analyze long-term observations of tritium, total alpha, and total beta activities in groundwater samples. The role of the hydrogeological conditions of the site, such as flow parameters, groundwater flow pattern, inter-aquifer downward groundwater leakage, and water-table fluctuations, in the evolution of contamination plumes has also been analyzed. In the field investigations, the integrity of the storage buildings to potential leaks was confirmed by different indirect methods. It was concluded that there is currently no significant release of radioactive components into groundwater at the LD RosRAO site and that the present conditions correspond to the stage of rehabilitation of the groundwater environment.

本文介绍了在放射性废物储存和处置设施场址（所谓的 LD RosRAO 场址，Sosnovy Bor，俄罗斯列宁格勒地区）的实地研究结果。该研究的目的是概述地下水污染的历史和发生，以回答放射性羽流是历史性的（由于事故形成，发生在放射性废物作业开始时）还是放射性溶液的释放地下水仍在发生。用于研究放射性污染演变的主要方法是分析地下水样品中氚、总α和总β活度的长期观察结果。场地水文地质条件的作用，如流量参数、地下水流型、含水层间地下水渗漏、和地下水位波动，在污染羽流的演变过程中也进行了分析。在现场调查中，通过不同的间接方法确认了储存建筑对潜在泄漏的完整性。得出的结论是，目前在 LD RosRAO 场地没有显着的放射性成分释放到地下水中，并且目前的条件与地下水环境的恢复阶段相对应。