Steam explosion major cause of human fatalities in volcanic eruptions. The 1986 Chernobyl nuclear disaster in Soviet Union was feared to cause major steam explosion (and resulting Europe-wide fallout) upon melting the lava-like nuclear fuel through the reactor's basement towards contact with residue fire-fighting water and groundwater. The threat was averted by frantic tunneling underneath the reactor in order to pump out water and reinforce underlying soil with concrete. When a pressurized container such as the waterside of a steam boiler ruptures, it is always followed by some degree of steam explosion. A common operating temperature and pressure for a marine boiler
Nuclear weapons and Ukraine of Independent States. In 1994 Ukraine agreed to destroy the weapons, and to join the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). As a republic in the Soviet Union, Ukraine was the base for the following nuclear forces: International relations theorist John Mearsheimer predicted a Ukraine without any nuclear deterrent was likely to be subjected to aggression by Russia, but this was very much a minority view at the time. A 2016 study argues that the denuclearization of Ukraine was not a "stupid mistake" and that it is unclear that Ukraine would be better off as a nuclear state.