Thirty months after the meltdowns at its Fukushima Daiichi nuclear power station, the Tokyo Electric Power Co. may have fumbled and fibbed one time too many.
Japan’s prime minister has announced that the national government will move to take control of radiation containment and decommissioning of the crippled reactors, where leaks of highly radioactive water have now been confirmed, out of Tepco’s hands.
And that’s good news, in the sense that government teams could hardly do worse than Tepco in managing the situation. But the enormity of Fukushima’s problems is such that it’s fair to wonder how much difference — apart from perhaps greater transparency — this management change can make.
Here is a waste-disposal problem that is growing larger, not smaller, with the passage of time, and is now revealed to be plagued by leaks that have yet to be located or counted, let alone repaired.
Running out of room for tanks
Tepco’s mid-August acknowledgement that 300 tons of contaminated water had leaked into the Pacific Ocean from a storage tank at the plant site may not have seemed terribly alarming, at least initially. At Fukushima, contaminated water is being collected at the rate of 400 tons every day.
More alarming was the report on Saturday that leaking water has produced high radiation readings in the ground near the storage tanks. From a brief account in the New York Times:
Tepco said it had found the high levels of radiation at four separate spots on the ground, near some of the hundreds of tanks used to store toxic water produced by makeshift efforts to cool the Fukushima Daiichi plant’s three damaged reactors. The highest reading was 1,800 millisieverts per hour, or enough to give a lethal dose in about four hours, Tepco said.
Saturday’s discoveries suggested that there may have been other leaks from the tanks, many of which appear to have been shoddily built as Tepco has scrambled to find enough storage space for the contaminated water being produced by the plant. However, Tepco said that it had found no evidence of fallen water levels in nearby tanks, making it unclear how much water, if any, may have leaked out, and whether any reached the Pacific, about 1,500 feet away.
About 430,000 tons of contaminated water, or enough to fill 170 Olympic-size pools, are stored in rows of tanks at the plant, which appears to be running out of open space to put them all.
I’ve never been quite sure why the Olympic-size swimming pool is the “social math” measure so often used to convey vast quantities of fluid, as opposed to, say, “gasoline tanker trucks” or “cement-mixer loads.” As applied Fukushima’s problems it has an added (and dark) significance given Japan’s concern that ongoing problems at the plant may cost it a chance to host the 2020 Olympics in Tokyo.
Lethal radiation levels
Searching for more depth and detail on the new crises, I found some highly impressive reporting in the British press and particularly from the Guardian’s Tokyo correspondent Justin McCurry. Some key points from his analysis published Monday:
- Even before Tepco’s disclosure of the 300-ton leak from storage, Japan’s environment ministry had reported that 300 tons a day of contaminated groundwater was seeping into the Pacific at Fukushima — having traveled from higher ground, down through the plant’s various underground structures and out the other side. (Guardian references are in metric tons.)
- The radiation levels reported Saturday at 1,800 millisieverts per hour had initially been gauged at a mere 100 millisieverts. Why the change? The first readings were taken with instruments whose scale topped out at 100.
- Until recent changes in Tepco’s monitoring protocol, “only two workers were dispatched twice a day to check the tanks, but did not carry personal radiation monitors and failed to keep proper records of their inspections.” Japan’s nuclear regulatory agency said other leaks or potential leaks had been seen near the storage tanks.
- There are 1,000 tanks at the Fukushima site, and they were built in haste. About one-third of them were fitted with plastic seals, rather than better rubber types, and failures of these seals are assumed to be the reason for the leaks. The tanks are already about 85 percent full.
- The leaks revealed over the weekend and earlier came as no surprise to Western nuclear specialists who have been watching Tepco’s struggle. A consultant to the German and French governments said:
The quantities of water they are dealing with are absolutely gigantic. What is the worse is the water leakage everywhere else — not just from the tanks. It is leaking out from the basements, it is leaking out from the cracks all over the place. Nobody can measure that.
- Japan’s rating of the new leaks as a level 3 incident on the international scale for severity of nuclear accidents is “an acknowledgment that the power station was at its greatest crisis since the reactors melted down after the tsunami in 2011. But some nuclear experts are concerned that the problem is a good deal worse than either Tepco or the Japanese government are willing to admit. “
Most estimates are that Japan faces a 30- or 40-year cleanup at Fukushima, in which contaminated water, soil and vegetation will be gathered in vast quantities, superheated or incinerated to concentrate the radioactive contents, then filtered and separated for different disposal methods based on radiation content. In the meantime, according to the Guardian:
The leaks threaten to delay [Prime Minister Shinzo] Abe’s plans to restart nuclear reactors, a move he says is necessary to support Japan’s economic recovery and improve Tepco’s tattered finances.
Of Japan’s 50 working nuclear reactors, only two are in operation. One of those was to be shut down on Monday evening to undergo routine checks, the other will go offline on 15 September, leaving Japan without atomic energy for only the second time in almost 50 years.