What Went Wrong at Fukishima? 24 Hours to Meltdown - Page 2
Even back up batteries failed and Reactor 1 suffered a complete power failure. The control room went dark and instrument panels stopped functioning. Cooling system pumps failed and the water which was supposed to be cooling radioactive fuel rods began to boil. Steam built inside the reactor building. Without working gauges and instruments, operators were not sure of how much water was left to cool the rods.
The non-electrical IC cooling system serving Reactor 1 had been shut down early in the crisis, due to it working too well. Now, without power plant operators were unable to reopen the valves, even manually.
Operators struggled to regain power at the plant. They scavenged batteries out of cars in the parking lot and called out a small fleet of power-generating trucks. However, the earthquake and tsunami ruined roads and mass evacuations clogged highways and these trucks promptly became stuck in traffic.
At 4:36 TEPCO finally officially alerted the Japanese government of the problem at Reactor 1.
Around 9 pm and working by flashlight, operators ingeniously powered up a few important instrument panels using the scavenged car batteries and were relieved to see that the water cooling the fuel rods in Reactor 1 seemed to holding up so far. Water levels were down, but the rods were not exposed.
Later, company analysis showed the instruments were incorrect. The water level had dropped so low the rods were completely exposed. Temperatures had topped 1300 °C (2372 °F) and the meltdown had already begun.
Around midnight, more instruments were brought online and showed that dangerous pressure inside the containment vessel had already exceeded its' maximum design and an explosion was a serious risk.
Teams struggled through the night and next day to vent the explosive pressure in the containment vessel and cool the rods. Power trucks finally arrived and prepared to restart pumps cooling the crippled reactor.Continued on the next page