The operator of the stricken Fukushima nuclear power plant in eastern Japan, the Tokyo Electric Power Co. (TEPCO), announced Monday that water had overflowed from a containment area surrounding storage tanks holding contaminated water.
TEPCO says heavy rains over the past few days have caused an overflow of water in 12 sections of the nuclear plant housing storage tanks for radioactively contaminated water. Levees were constructed around the storage tanks as an additional preventative measure but these earth banks cannot provide a permanent solution to escape of water as they are prone, not only to overflow as recent bad weather has shown, but also to water seeping through, and high groundwater levels subverting the surface protection.
Disaster struck the Fukushima Daiichi Nuclear Plant on March 11, 2011. An earthquake in the western Pacific was swiftly followed by a massive tsunami that struck Japan’s eastern seaboard. As a result, several of Fukushima’s reactors suffered serious damage.
Since the disaster, plant operators TEPCO have wrestled with the problem of how to contain highly radioactive water which was used to cool the now-breached reactor assemblies as well as thousands of spent fuel rods stored at the plant.
There have been leaks of radioactive water into the Pacific Ocean on a number of occasions. The containment problem has been compounded by groundwater flowing into the disaster-struck plant adding to the total amount of water requiring safe containment.
Presently, all Fukushima’s reactors are offline and are likely to remain so in the foreseeable future.
Tests on the latest samples showed the presence of beta radiation in water which had escaped beyond containment levees. Examinations are also being carried out to ascertain the quantity of water which may have leaked from on-site storage tanks and the levels of any such radiation.
The possibility of an inundation at Fukushima had been well-telegraphed. For days beforehand, Japanese meteorologists had been warning of the imminent arrival of Typhoon Wipha, bringing heavy rains in from the Pacific in its wake.
Prophetically, The Washington Post reporting Oct. 15 on the approaching typhoon, wrote, “While Tokyo Electric plans to pump rainwater into [Fukushima’s] holding tanks, check it for radioactivity, and release it only if uncontaminated, the fact that they haven’t been able to contain leaks raises concerns over the further escape of radioactive water.”
Typhoon Wipha had been described as the “storm of the decade” and the apparent lack of preparedness on the part of TEPCO, operators of the Fukushima plant, has once again been criticized in Japanese media.
The Japanese Daily Press claims the worst effects of Typhoon Wipha could have been minimized had proper precautions been taken. It blames TEPCO for ignoring warnings of imminent very severe weather.
On the worrying question of contaminated groundwater, which looks set to remain an ongoing problem at Fukushima, the Japan Times reported soaring radiation readings Friday.
Samples taken by TEPCO at an observation well 15 meters from a storage tank that leaked 300 tons of highly radioactive waste last August showed levels of 400,000 becquerels per liter of beta ray-emitting substances such as strontium. The reading from Friday’s sample was 6,500 times greater than the 61 becquerels recorded in a sample taken just two days previously.
With more than a hint of sarcasm, the Japanese Daily Press reports TEPCO said the radioactive-contaminated water spilled “due to heavy rain in the Tohoku region.” The newspaper goes on to say the latest leakage at Fukushima will most likely increase people’s concerns and doubts on the TEPCO’s ability to clean up the defunct nuclear plant.
The inundation of the containment area occurred just days after further concerns surfaced on the safety of one of the buildings at Fukushima used to house spent, but still highly radioactive, fuel rods.
As part of routine maintenance prior to the 2011 tsunami, the fuel rods were moved to a storage area. The storage zone is located the equivalent of 10 storeys up in a building that suffered heavy structural damage during the 2011 earthquake and tsunami.
As the accompanying video shows, now there are concerns that the storage building may collapse leading to a possible second Fukushima nuclear disaster.
The Washington Post
Japanese Daily Press