The Republics of Slovenia and Croatia are the owners of the Krško nuclear power plant (50:50), which will operate until 2043. The power plant is located on the border between Slovenia and Croatia on Vrbina site. All radioactive waste generated by the operation of the nuclear power plant, as well as the one that will be produced during its decommissioning, is in 50:50 ownership of the two states and they need to find a common solution for its disposal. Slovenia proposed to dispose the waste at the place of its origin (territorially it would be in Slovenia), while Croatia continually changed its demands, and by that avoiding common solution. For a long time, Croatia was claiming that joint disposal with Slovenia was too expensive, and when Slovenia started to make inexpensive and acceptable offers Croatian officials changed the story. Then Croatia demanded to store radioactive waste, spent nuclear fuel and other waste material in one place.
The main catch is that waste material include not only those from the Krško nuclear power plant, but from all over Croatia. Slovenia does not accept all waste material from Croatia, so Croatia is pushing for the construction of its own landfill.
The story that Croatia needs to build its landfill in Trgovska Gora starts in 1999 when it emerged in public. From then protests and petitions (13000+ signatures) are being organized. Because Trgovska Gora located at the border of Croatia and Bosnia and Herzegovina (BiH) it triggered the revolt of the population on both sides of the border.