Radiation in seawater a million times legal limit
TOKYO—Radiation in seawater on the shoreline off the crippled Fukushima Dai-ichi Nuclear Power Station has measured several million times the legal limit, prompting the government to set its first radiation safety standards for fish on Tuesday.
Tokyo Electric Power Co. (TEPCO), the plant operator, insisted that the radiation posed no immediate danger as it would rapidly disperse in the vast Pacific Ocean, but an expert said exposure to the highly concentrated levels of radiation near the plant could cause immediate injury and that the leaks could result in residual contamination of the sea in the area.
Reports that radiation was building up in fish led the government to create an acceptable radiation standard for fish for the first time. Some fish caught on Friday off Japan’s coastal waters would have exceeded the new provisional limit.
“Even if the government says the fish is safe, people won’t want to buy seafood from Fukushima,” said Ichiro Yamagata, a fisherman who used to live within sight of the nuclear plant and has since fled to a shelter in Tokyo.
“We probably can’t fish there for 10 to 20 years,” he said.
7.5 million times
As the engineers battled to prevent a catastrophe at the nuclear plant, TEPCO announced that samples taken on April 2 from seawater near one of the reactors contained 7.5 million times the legal limit for radioactive iodine. Two days later, however, that figure dropped to 5 million.
TEPCO said in a statement that even the large amounts would have “no immediate impact” on the environment.
Experts agree that radiation dissipates quickly in the Pacific Ocean, but direct exposure to the most contaminated water measured would lead to “immediate injury,” said Yoichi Enokida, a professor of materials science at Nagoya University’s graduate school of engineering.
Nagoya added that seawater may be diluting the iodine, which decays quickly, but the leak also contains long-lasting cesium 137.
Both elements can build up in fish, though iodine’s short half-life means it does not stay there for very long. The long-term effects of cesium, however, will need to be studied, he said.
“It is extremely important to implement a plan to reduce the outflow of contaminated water as soon as possible,” Nagoya said.
Highly radioactive cesium has also been found at levels above safety limits in tiny kounago fish in waters off Ibaraki prefecture, south of Fukushima, local media reported.
Going to get worse
Radioactive cesium, which has a half-life of 30 years, collect in larger fish as they consume smaller fish, which means the problem may grow over time.
Marine biologists have expressed concern over the Japanese government’s pronouncement that it could take months to stem the release of radioactive material from the plant.
“We’re seeing the levels of radioactive materials in the water increase, which means this problem is going to continue to get worse and worse,” said Kenya Mizuguchi, emeritus professor of maritime science and technology at Tokyo University.
Radioactive water
TEPCO announced the high levels of radiation in seawater a day after the plant operator began dumping more than 11,500 tons of low-radioactive water into the Pacific Ocean in order to make room in a storage facility for the more highly radioactive water in the six-reactor complex.
Radiation has been pouring from the nuclear plant into the sea since March 11 when a 9-magnitude earthquake spawned a massive tsunami that inundated the complex. Thousands were forced to evacuate from the area near the plant because of radiation concerns.
Over the weekend, emergency workers discovered a crack in one of the reactors where highly contaminated water was spilling directly into the ocean.
In desperation, TEPCO engineers have turned to what are little more than home remedies to stem the flow of contaminated water. On Tuesday, they used “liquid glass” in the hope of plugging cracks in a leaking concrete pit.
“We tried pouring sawdust, newspaper and concrete mixtures into the side of the pit (leading to tunnels outside Reactor No. 2), but the mixture does not seem to be entering the cracks,” said Hidehiko Nishiyama, deputy director general of Japan’s Nuclear and Industrial Safety Agency.
“We also still do not know how the highly contaminated water is seeping out of Reactor No. 2,” Nishiyama said.
Workers are struggling to restart the cooling pumps—which recycle water—in four damaged reactors.
Their problem is that until those pumps are fixed, they must pump in water from the outside to avert a full meltdown that would release more toxic radioactivity into the environment.
These makeshift process, however, created 60,000 tons of highly contaminated water in the nuclear plant.
This forced TEPCO to start releasing 11,500 tons of low-level radioactive water into the sea after it ran out of storage capacity for the more highly contaminated water. The release will continue until Friday.
Serious blow
The world’s worst nuclear crisis since the Chernobyl disaster in 1986 has dealt a serious blow to TEPCO, Japan’s biggest utility.
TEPCO shares plunged to a record low of 363 yen on Tuesday, falling below its previous all-time closing low of 393 yen in December 1951.
Since the quake, TEPCO’s share price has nose-dived to a staggering 80 percent. The Tokyo Stock Exchange said investors had dumped TEPCO shares worth 1.06 trillion yen ($60 billion) since March 11.
In what could be an effort to shore up its reputation, TEPCO vice president Takashi Fujimoto said the utility was offering 20 million yen ($240,000) to 10 towns affected by a mandatory evacuation zone.
Fujimoto called the cash “apology money” and noted that one town had refused it because it disagreed with the approach. He did not give further details.
TEPCO faces a huge bill for the damage caused by its crippled reactors, but said the utility must first assess the extent of damage before paying actual compensation.
Costliest disaster
The tsunami pulverized about 400 kilometers of the northeastern coast, flattening whole towns and cities and killing nearly 28,000 people. The giant wave left thousands homeless and Japan’s northeast coast a wreck.
The world’s costliest natural disaster has caused power blackouts and cuts to supply chains, threatening Japan’s economic growth and the operations of global firms from semiconductor makers to shipbuilders.
Fujimoto said TEPCO wanted to avoid having to impose rolling power blackouts in summer, when demand surges due to heavy use of air-conditioning. Analysts say blackouts could cause the biggest economic damage to Japan.
The world’s biggest auto maker, Toyota Motor Corp., plans to shut down some US factories due to supplies in Japan drying up.
The company, which built nearly 1.5 million cars and trucks in North America last year, said it did not know how many of its 13 plants would be affected.
The nuclear crisis alone is likely to lead to one of the country’s largest and most complex ever set of claims for civil damages, handing a huge bill not only to debt-laden TEPCO but also to the fiscally strained government. Reports from Associated Press, Reuters and Agence France-Presse
