Radioactive water likely leaking to Pacific

TOKYO (AP) — Japan’s nuclear regulator says radioactive water from the crippled Fukushima power plant is probably leaking into the Pacific Ocean, a problem long suspected by experts but denied by the plant’s operator.

Officials from the Nuclear Regulation Authority said a leak is “strongly suspected” and urged plant operator Tokyo Electric Power Co. to determine where the water may be leaking from and assess the environmental and other risks, including the impact on the food chain. The watchdog said Wednesday it would form a panel of experts to look into ways to contain the problem.

The watchdog’s findings underscore TEPCO’s delayed response in dealing with a problem that experts have long said existed. On Wednesday, the company continued to raise doubts about whether a leak exists.

TEPCO spokesman Noriyuki Imaizumi said the increase in cesium levels in monitoring well water samples does not necessarily mean contaminated water from the plant is leaking to the ocean. TEPCO was running another test on water samples and suspects earlier spikes might have been caused by cesium-laced dust slipping into the samples, he said. But he said TEPCO is open to the watchdog’s suggestions to take safety steps.

Marine biologists have warned that the radioactive water may be leaking continuously into the sea from underground, citing high radioactivity in fish samples taken near the plant.

Since May, TEPCO has reported spikes in cesium levels in underground water collected from a coastal observation pit, while the water-soluble element strontium showed high levels in seawater samples taken in areas just off the coast of the plant. The company says most of the contamination has been there since the 2011 accident.

TEPCO has said it has detected “no significant impact” on the environment. It says cesium tends to be absorbed in the soil, and denies water contaminated with that element reached the sea.

But the Nuclear Regulation Authority said Wednesday that samples from both the pit water and coastal seawater indicated that contaminated underground water likely had reached the sea.

Watchdog chairman Shunichi Tanaka said he thinks that the seawater contamination has been happening since the accident, but that it was worst early in the crisis.

“What’s most important is to minimize the leak to the outside and reduce the impact on the human society,” he said.

Most fish and seafood from along the Fukushima coast are barred from the domestic market and from being exported. Seafood caught north and south of Fukushima are regularly tested for radiation to make sure they are safe for consumption. In the wider ocean, the contaminated water becomes too diluted to be harmful.

The safety of fish and other foods from around Fukushima remains a concern among ordinary Japanese, who are among the world’s highest per capita consumers of seafood.

TEPCO says it has taken steps to prevent seawater contamination but that it is impossible to completely prevent the contamination from spreading.

Atsunao Marui, underground water expert at the National Institute of Advanced Industrial Science and Technology, said there is a possibility of new leaks from reactor buildings. He said TEPCO will have to expand its seawater sampling and its investigation of the underground water system to assess the extent of possible contamination.

“It is important to apply several layers of protection,” he told NHK television.

The plant still runs on jury-rigged systems to cool the reactors, and managing the contaminated water and its storage has been a chronic headache.

“When something unexpected happens, we can only take stopgap measures, which shows how unstable Fukushima Dai-ichi still is,” Tanaka said. “Given the situation, we can only use the best of our wisdom and do what we can.”

Associted Press, July 11, 2013
http://mainichi.jp/english/english/newsselect/news/20130711p2g00m0dm045000c.html

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Regulators suspect toxic water at Fukushima plant contaminating sea

TOKYO (Kyodo) — The Nuclear Regulation Authority said Wednesday that it is “strongly suspected” that highly radioactive water at the Fukushima Daiichi nuclear power plant is seeping into the ground and contaminating the Pacific Ocean.

“We must find the cause of the contamination...and put the highest priority on implementing countermeasures,” NRA Chairman Shunichi Tanaka told a meeting of its commissioners after they had studied recent surveys on the radiation level of groundwater at the plant, which has shown radioactive substances such as cesium and tritium existing in high density.

Plant operator Tokyo Electric Power Co. believes the source of contamination to be a pit from which highly radioactive water was found seeping into the sea in April 2011, shortly after the nuclear crisis began at the plant, but the NRA said that toxic water in the area may not be the only cause.

According to TEPCO, the density of radioactive cesium in groundwater collected Tuesday from an observation well by the sea soared over 100 times higher than the level in water taken Friday.

The groundwater sample contained 11,000 becquerels of cesium-134 per liter and 22,000 becquerels of cesium-137 per liter.

The water also contained 900,000 becquerels of other radioactive substances that emit beta rays, such as strontium.

TEPCO has taken measures to enclose the contaminated seawater in areas near the plant, but they cannot completely prevent the spread of every radioactive material to the wider sea area, according to an NRA official.

TEPCO has said it has detected “no significant impact” on the environment.

Kyodo News, July 10, 2013

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 Radiation surge mystifies Tepco — Cesium soars in water under No. 1 plant

Tokyo Electric Power Co. on Tuesday reported a surge in radioactive cesium levels in groundwater in an observation well at its Fukushima No. 1 nuclear power plant.

This signals radioactive contamination is spreading under the disaster-stricken facility.

Water sampled from the well Monday contained 9,000 becquerels of cesium-134 per liter and 18,000 becquerels of cesium-137, both about 90 times the levels found Friday, Tepco said. The well is near the turbine building for reactor 2 and about 25 meters from the plant’s harbor.

“We still don’t know why the level of radiation surged, but we are continuing efforts to avert further expansion of contamination,” a Tepco spokesman stated.

Government guidelines permit cesium-134 at 60 becquerels per liter and -137 at 90 becquerels. Once ingested, the substances accumulate in muscle and bone and are believed to cause cancers.

The water collected Monday also contained 890,000 becquerels of substances that include strontium, which emits beta radiation, compared with 900,000 becquerels found in groundwater sampled from the well Friday.

Groundwater cesium levels in the well and other observation wells had remained low until recently. Readings were often below the minimum detectable levels.

Explaining the reason for the low contamination in groundwater, Tepco had said cesium can be easily absorbed by soil.

Following the latest findings, however, Tepco officials now say they do not know why the cesium levels have surged.

“Mud that has absorbed radioactive cesium may have got mixed with the water. We will measure the (contamination of the) water again,” a Tepco official told reporters at the Fukushima Prefectural Government office.

The official also said Tepco will determine if radioactive substances are seeping into the sea after studying its seawater survey.

The company also said groundwater collected Monday from a well located near the reactor 3 turbine building and about 23 meters from the port was found to have contained 1,700 becquerels of beta radiation-emitting substances per liter.

The reading was about 20 times the level detected Thursday and the highest for such substances in the well.

The new readings came two days after Tepco said tritium, a radioactive isotope of hydrogen used in glow-in-the-dark watches, was present at levels 10 times the permitted rate.

Tepco said in late June it had detected the highly toxic strontium-90, a byproduct of nuclear fission that can cause bone cancer if ingested, at levels 30 times the permitted rate.

The substances, which were released by the meltdowns of reactors at the plant in the aftermath of the huge tsunami of March 2011, were not absorbed by soil and have made their way into groundwater.

Subsoil water usually flows out to sea, meaning these two substances could normally make their way into the ocean, possibly affecting marine life and ultimately impacting humans who eat sea creatures.

Jiji Press, Kyodo News, AFP-Jiji Press, Jul 9, 2013
http://www.japantimes.co.jp/news/2013/07/09/national/cesium-soars-in-water-under-no-1-plant/#.Uep4lErS-gM

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Cesium readings further climb in groundwater at Fukushima plant

TOKYO (Kyodo) — Radioactive cesium readings in groundwater samples taken from an observation hole by the sea at the Fukushima Daiichi Nuclear Power Station increased further on Tuesday compared with the samples taken the day before, Tokyo Electric Power Co. said early Wednesday.

Tuesday’s samples showed 11,000 becquerels of cesium-134 per liter and 22,000 Bq/L of cesium-137. They were 111 times and 105 times greater than the samples on Friday.

Monday’s samples registered 9,000 Bq/L of cesium-134 and 18,000 Bq/L of cesium-137.

The reason for the spike in readings remains unknown. TEPCO said it will intensify the monitoring.

Kyodo News, July 10, 2013
http://mainichi.jp/english/english/newsselect/news/20130710p2g00m0dm036000c.html

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 Probe launched after contractor JDC dumped radioactive water into river for irrigation in Fukushima

JDC Corp., a midsize general contractor, discharged 340 tons of radioactive water into the Iizaki River, which is tapped for irrigation in Minamisoma, Fukushima Prefecture, during government-sponsored decontamination work it was involved in, company sources said Thursday.

Local government officials claimed they were never informed of the action. But JDC sources said the dumping occurred after it received assurances from the Japan Atomic Energy Agency, which contracted it to carry out the decontamination work, that the state body had informed the local governments about the discharge in advance and no problem was anticipated.

The company had not been aware that water from the river would be used for agricultural purposes, the sources added.

A Minamisoma official said the city never received any explanation about the dumping, nor had Fukushima Prefecture, according to a prefectural official.

The Japan Atomic Energy Agency claimed it had verbally notified the city and prefecture, but had not established an agreement in writing.

The Environment Ministry is investigating, suspecting information was not properly conveyed in accordance with law.

The radioactive water was accumulated during agency-sponsored decontamination projects JDC was involved in between December 2011 and February 2012.

JDC engaged in radiation decontamination work in and around Kanabusa elementary school in Minamisoma and accumulated 609 tons of tainted water, according to JDC data made available to Kyodo News.

Of that amount, 269 tons was treated by specialists and the remaining 340 tons was discharged into the Iizaki River, which is used to irrigate rice paddies.

The discharged water included 60 tons with radiation levels at 100 to 121 becquerels per liter, exceeding the agency’s maximum allowable standard of 90 becquerels, the company data indicate. Radioactive substances in the discharged water totaled 16 million becquerels.

The agency approved a JDC plan to transport radiation-contaminated water to a certain collection center in December 2011 and submitted the plan to the Minamisoma Municipal Government.

The city said that at the time, it had expected the tainted water to be taken away.

Kyodo News, July 12, 2013
http://www.japantimes.co.jp/news/2013/07/12/national/probe-launched-after-contractor-jdc-dumped-radioactive-water-into-river-for-irrigation-in-fukushima/#.Ues5SUrS-gM

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