Saturday 24 August 2013

Fukushima - mainstream coverage


Radioactive Groundwater at Fukushima Nears Pacific
Deep beneath Fukushima's crippled nuclear power station, a massive underground reservoir of contaminated water that began spilling from the plant's reactors after the 2011 earthquake and tsunami has been creeping slowly toward the Pacific.


23 August, 2013


Now, 2 1/2 years later, experts fear it is about to reach the ocean and greatly worsen what is fast becoming a new crisis at Fukushima: the inability to contain vast quantities of radioactive water.

The looming crisis is potentially far greater than the discovery earlier this week of a leak from a tank that stores contaminated water used to cool the reactor cores. That 300-ton (80,000-gallon) leak is the fifth and most serious from a tank since the March 2011 disaster, when three of the plant's reactors melted down after a huge earthquake and tsunami knocked out the plant's power and cooling functions.

But experts believe the underground seepage from the reactor and turbine building area is much bigger and possibly more radioactive, confronting the plant's operator, Tokyo Electric Power Co., with an invisible, chronic problem and few viable solutions. Many also believe it is another example of how TEPCO has repeatedly failed to acknowledge problems that it could almost certainly have foreseen — and taken action to mitigate before they got out of control.

It remains unclear what the impact of the contamination on the environment will be because the radioactivity will be diluted as it spreads farther into the sea. Most fishing in the area is already banned, but fishermen in nearby Iwaki City had been hoping to resume test catches next month following favorable sampling results. Those plans have been scrapped after news of the latest tank leak.

"Nobody knows when this is going to end," said Masakazu Yabuki, a veteran fisherman in Iwaki, just south of the plant, where scientists say contaminants are carried by the current. "We've suspected (leaks into the ocean) from the beginning. ... TEPCO is making it very difficult for us to trust them."

To keep the melted nuclear fuel from overheating, TEPCO has rigged a makeshift system of pipes and hoses to funnel water into the broken reactors. The radioactive water is then treated and stored in the aboveground tanks that have now developed leaks. But far more leaks into the reactor basements during the cooling process — then through cracks into the surrounding earth and groundwater.

About 1,000 tons of underground water from the mountains flows into the plant compound each day, of which 400 tons seep into the reactor and turbine basements and get contaminated. The remaining 600 avoids that area, but at least half of it is believed to eventually come in contact with contamination elsewhere before entering the sea, according to an estimate by Japan's Agency for Natural Resources and Energy.

Scientists, pointing to stubbornly high radioactive cesium levels in bottom-dwelling fish since the disaster, had for some time suspected the plant was leaking radioactive water into the ocean. TEPCO repeatedly denied that until last month, when it acknowledged contaminated water has been leaking into the ocean from early in the crisis. Even so, the company insists the seepage is coming from part of a network of maintenance tunnels, called trenches, near the coast, rather than underground water coming out of the reactor and turbine area.

"So far, we don't have convincing data that confirm a leak from the turbine buildings. But we are open to consider any possible path of contamination," said TEPCO spokesman Yoshimi Hitosugi.

The turbine buildings at the Fukushima Dai-ichi plant are about 150 meters (500 feet) from the ocean. According to a Japan Atomic Energy Agency document, the contaminated underground water is spreading toward the sea at a rate of about 4 meters (13 feet) a month.

At that rate, "the water from that area is just about to reach the coast," if it hasn't already, said Atsunao Marui, an underground water expert at the National Institute of Advanced Industrial Science and Technology who is on a government committee studying the contaminated water problem. "We must contain the problem as quickly as possible."

TEPCO, nationalized and burdened with the astronomical cleanup costs, has been criticized for repeatedly lagging in attempts to tackle leakage problems. As a precautionary step, it has created chemical blockades in the ground along the coast to stop any possible leaks, but experts question their effectiveness. After a nearly two-year delay, construction of an offshore steel wall designed to contain contaminated water has begun.

The utility has also proposed building frozen walls — upside down comb-shaped sticks that refrigerate surrounding soil — into the ground around the reactor areas, but that still has to be tested and won't be ready until 2015 if proved successful.

Prime Minister Shinzo Abe earlier this month announced that the government would intervene and provide funding for key projects to deal with the contaminated water problem.

"This is a race against the clock," said Toyoshi Fuketa, a commissioner on Japan's Nuclear Regulation Authority.

Compounding TEPCO's problems is the new leak discovered this week. Most of the 300 tons is believed to have seeped into the ground, but some may have escaped into the sea through a rainwater gutter, said Zengo Aizawa, the company's executive vice president.

That, too, may be a harbinger of more problems ahead.

Some 1,000 steel tanks built across the plant complex contain nearly 300,000 tons (300 million liters, 80 million gallons) of partially treated contaminated water. About 350 of the tanks have rubber seams intended to last for only five years. TEPCO spokesman Masayuki Ono said the company plans to build additional tanks with welded seams that are more watertight, but will have to rely on rubber seams in the meantime.

Shinji Kinjo, a regulatory official in charge of the Fukushima disaster, said the rubber-seam tanks were mostly built in a rush when the contaminated water problem started, and often lacked adequate quality tests and require close attention.

Workers spotted two more questionable tanks during an inspection Thursday.

After his inspection Friday, Fuketa, the regulatory commissioner, said that the plant's twice-daily leak-spotting patrols were "sloppy," and that there were hardly any protective measures taken in anticipation of a potential tank leak.

"It's like a haunted house, one thing happening after another," said Nuclear Regulation Authority Chairman Shunichi Tanaka, referring to the spate of problems at the plant. "But we must take any steps that would reduce risks to avoid a fatal accident."

Leaks of highly contaminated water from the aboveground tanks aggravate the groundwater problem.

"Any contamination in the groundwater would eventually flow into the ocean. That is very difficult to stop even with barriers," said Ken Buesseler, a marine chemist at the Woods Hole Oceanographic Institution in Massachusetts. He found that radioactive cesium levels in most fish caught off the Fukushima coast hadn't declined in the year following the March 2011 disaster, suggesting that the contaminated water from the reactor-turbine areas is already leaking into the sea.

But TEPCO hasn't provided the details he and other scientists need to further assess the situation.


TEPCO’s Fukushima inspections inadequate – Japan nuclear regulator
Japan’s nuclear regulator has concluded that the Fukushima nuclear plant’s operator was inadequate in its inspection of radioactive water tanks after news of yet another leak. TEPCO earlier admitted it will now require international help.


RT,
23 August, 2013



On Friday, the Nuclear Regulation Authority (NRA) Commissioner Toyoshi Fuketa visited the destroyed Fukushima Daiichi nuclear power plant to inspect the ongoing radioactive cleanup efforts. Fuketa’s comments follow those of the NRA chairman Shunichi Tanaka, who earlier this week worried that the makeshift giant radioactive containers were prone to failure.

"Fundamentally, for a facility holding that kind of radioactive water, they did not take action that foresaw the risks of possible leaks," Fuketa said at a press briefing in Hirono. "On top of that – and this is an impression I had before my visit – I can't help but say that the inspections were careless."

The plant operator said on Thursday that a new radiation spill has been detected near the storage tanks, which sparked fears of newer leaks before the old ones had been dealt with.

Furthermore, the company has been accused of failing to properly document inspections, leading to misspent resources and problems cropping up that should have been noticed before, according to Fuketa.

Japan has decided to raise the gravity of the latest Fukushima leak to Level Three, which is considered a “serious radiation incident” on the International Nuclear Event Scale (INES) for radiological releases. The most dangerous, Level Seven, has only been applied twice – for the Chernobyl catastrophe in 1986 and for the meltdown of three reactors at the Fukushima plant.

TEPCO has also now admitted it will be seeking international expertise to help out with the leaks.

"Many other countries outside of Japan have experienced decommissioning reactors, so we hope we can consult them more and utilize their experience,” TEPCO’s vice-president, Zengo Aizawa, said at a news conference on Wednesday night.

"In that sense we need support - not only from the Japanese government, but from the international community - to do this job."

The UN’s International Atomic Energy Agency (IAEA) said that it was ready to help out, if needed, and that it viewed the situation “seriously,” just as China was saying it was “shocked” to hear that radioactive water leaks are still continuing. The neighbor has urged Japan to provide it with information “in a timely, thorough and accurate way.”

Almost two-and-a-half years since a lethal combination of a tsunami and an earthquake crippled the power plant and caused a multitude of subsequent problems, TEPCO is faced with its most serious problem yet. This is after the recent discovery that radioactive water has been leaking from the plant’s storage tanks into the Pacific at an alarming rate of 300 tons a day.

An aerial view shows Tokyo Electric Power Co. (TEPCO)'s tsunami-crippled Fukushima Daiichi nuclear power plant and its contaminated water storage tanks (bottom) in Fukushima, in this photo taken by Kyodo August 20, 2013. (Reuters/Kyodo)


Numerous contingency measures have been thought of for the problems that keep cropping up continuously in different parts of Fukushima – including leaking radioactive water, as well as a danger that Reactor 4 would collapse on itself. The structure holds upwards of 1,300 nuclear fuel rods containing 14,000 times the amount of radiation that the Hiroshima bomb released.

A never-before-attempted operation is in the works. It will involve the manual removal of nuclear fuel rods from Reactor 4 by way of a manually-operated crane – not by computer. Any mistakes could lead to contamination on an unprecedented scale. All this is happening at a time when the soil beneath Reactor 4 is slowly sinking.

The tanks, which are used to keep the coolant that prevents the damaged reactors from overheating dangerously, are considered to be unsuitable because they were made for other industrial purposes. They were adapted following the emergency, but they are nearly full.

TEPCO estimates that it has already reached 85 percent capacity, although plans to create a more permanent facility have so far not materialized. The latest leak was the fifth time that toxic water escaped from a basin.

The operator has been slow in measuring the levels of radioactive elements that have flowed out of the station, as well as publishing its data. TEPCO finally revealed this month that highly unsafe tritium and cesium levels had been detected in the seawater near the plant. A concentration of these elements could damage the marine environment and build up in marine life, possibly endangering humans further up the food chain.

The catastrophe of March 11, 2011, caused the meltdown of nuclear fuel rods at three of the plant’s reactors, leading to a contamination of air and sea, as well as crippling the region’s agriculture and fishing activities, gravely damaging the economy for years to come. On top of this, costs required for the cleanup, as well as to sustain the nation’s needs and compensation payouts, are projected to be in the billions – a fact that has recently caused the Japanese government to step in and start contributing money to TEPCO’s efforts.

The Fukushima nuclear meltdown has been called the worst radioactive event since the Chernobyl nuclear disaster of 1986. And with protracted cleanup efforts expected to last decades, by multiple estimates, any misstep could lead to a cascading chain of dangerous radioactive events, fallout researcher Christina Consolo told RT. She made special reference to the upcoming operation for the manual removal of fuel rods from Reactor 4.

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