I don't know whether Belarus signed the Espoo convention, or is a member of Association of Regulators of Western Europe, etc.. If your point is, "why don't my neighbours play according to my rules", I can see where you're coming from, but not necessarily agree.

Belarus suffered the most from Chernobyl accident, with 70% of fallout in its territory. And Chernobyl NPP wasn't even in their country. I might think that they are well positioned to do everything they can to prevent any nuclear accident happening in their NPP.