The type of venting system meant to prevent hydrogen explosions at U.S. nuclear power plants failed to work at Japan’s damaged Fukushima Daiichi plant, according to a report from The New York Times. The revelation is now raising serious concerns about how the venting system would perform at nuclear plants in the U.S. should a severe emergency occur here.
The Fukushima Daiichi plant, built by General Electric, was damaged by a massive earthquake and tsunami that hit Japan on March 11. The failure of the venting system allowed hydrogen explosions to occur that sent large amounts of <"http://www.yourlawyer.com/topics/overview/Radiation-Exposure-Environmental-Contamination-Dumping-Spill-Lawsuit">radioactive materials into the air. While use of the venting system still would have allowed radiation to escape into the atmosphere, it would have been much less than what was released in the explosions.
Initially, the hydrogen explosions were blamed primarily on indecisive Japanese officials who delayed using the vent system at Fukushima. But according to the Times, documents and interviews with experts indicate “mechanical failures and design flaws in the venting system” also led to delays. When workers were finally told to use the vents, the system did not respond.
There were several reasons the vents ultimately failed to work, the Times said. Among other things, they relied on the same sources of electricity as the rest of the plant, which were knocked out by the earthquake and tsunami. Backup generators also didn’t work because they were located in the basement, resulting in damage from the tsunami. It also seems that valves used to open the vents were damaged, and those would not work even when attempts were made to manually operate them.
According to The New York Times:
“The results of the failed venting were disastrous.
Reactor No. 1 exploded first, on Saturday, the day after the earthquake. Reactor No. 3 came next, on Monday. And No. 2 exploded early Tuesday morning.
With each explosion, radioactive materials surged into the air, forcing the evacuation of tens of thousands of earthquake survivors living near the plant, contaminating crops and sending a faint plume of radioactive isotopes as far as the United States within days”
According to the Times, the venting system used at Fukushima was mandated in the 1980s for use at U.S. nuclear plants outfitted with boiling water reactors that used General Electricâ€™s Mark I containment system . The “improved” venting system was ordered after it was determined existing systems were not strong enough to handle pent-up pressure inside the reactors in an emergency, the Times said. But because many of the system’s numerous safeguards were reliant on electricity, it would be useless if a plant lost all power – as happened in Japan, experts say.
Before it was known exactly how the venting system performed – or failed to perform – in Japan, American officials had said U.S. plants would be safe from a similar disaster because of that very system. Now, according to the Times, it will be up to nuclear regulators to determine if U.S. plants using that venting system will need a major retrofitting or redesign to ensure their safety in a major catastrophe.