ROKO (the name derives from Slovenian Radioactivity in the Environment) is a database which contains data on measurements of radioactivity in the Republic of Slovenia. Programs for monitoring of levels of radioactivity in the environment as a consequence of global contamination due to nuclear bomb tests and the Chernobyl accident have been continuously carried out. In addition to the data on levels of radioactive contamination of the environment, the SNSA has also gathered data from the Krško NPP, the Žirovski Vrh Mine, the Low and Intermediate Level Waste Depository and the Reactor Centre at Brinje.
Beside regular monitoring programs, the SNSA orders individual studies of a particularly interesting aspect of contamination in the environment. All data from regular programs and most of the data gathered in individual studies carried out since since 1961 have been entered into the database.
The database enables easy entering and reviewing of records. The measurements are mostly carried out at the same locations every year, enabling us to monitor radioactive contamination trends. The diagram shows the measurements of the concentration of Cs-137 in soil samples in Ljubljana.

Natural decay of radionuclides produced in nuclear tests and Chernobyl accident causes slow decrease of concentration in nature.