1:23:04. With every decision, they have pulled this reactor back, like a slingshot, further than anyone has ever pulled. Now the test begins. The pumps are shut down, and they’ve let go. The pumps stop moving water through the reactor. Uranium fuel is now unchecked by fresh coolant, unchecked by control rods. The balance immediately swings in the opposite direction. In less than a second, reactivity increases. Inside the core, the remaining water is quickly converting to steam. A void is being created. There is no fresh water to replace it. Steam increases reactivity, increases heat, increases steam, increases reactivity. The remaining xenon decays away. The power is rising. There is nothing left to stop it. [...] 1:23:45. Explosion. In the instant the lid is thrown off the reactor, oxygen rushes in. It combines with hydrogen and superheated graphite. The chain of disaster is now complete.
