While experts note that Zaporizhzhia’s six reactors are well shielded by their hardened concrete housings, the shelling could trigger fires or, perhaps, operator error. This, in turn, could lead to a breakdown of cooling systems and, should that not be contained (a complex process that becomes more difficult in the context of an on-going shooting war), could lead to a meltdown.

A senior U.S. official with whom I spoke said, “The situation is very fragile. The longer the staff goes in these very stressful circumstances, the longer the facility goes without the IAEA being able to support the security of the plant, every day that passes makes it more fragile.” The official added, “The thing I am most concerned about is the inadvertent fog of war or poorly disciplined troops or weapons malfunctioning leading to a disaster.” Even if that is not the goal of the Russians, the official noted, stressing that it is in the interest of neither side to see the plant destroyed, the risk of unintended consequence has risen immeasurably given Moscow’s reckless tactics.

When asked what could be done to reduce the risk, the official (an expert in nuclear energy matters) kept it simple: “The risk could be reduced to zero by Russia withdrawing.”