Radiation Leak Found at Fukushima

Japan Nuclear Disaster Update – Apr 2

Radiation near Reactor 2 in Fukushima NPP measures 1,000 millisieverts per hour

TEPCO, operator of the crippled Fukushima NPP, has found radioactive water leaking into the sea from a cracked concrete duct near Reactor 2, NHK said.

A TEPCO employee points to the inlet of a cracked concrete duct containing power cables near Reactor 2 at Fukushima Daiichi Nuclear Power Plant where contaminated water,  emitting radiation at 1,000 millisieverts per hour, is  leaking into the sea, April 2, 2011. Source: TEPCO

“With radiation levels rising in the seawater near the plant, we have been trying to confirm the reason why, and in that context, this could be one source,” said deputy head of Japan’s Nuclear and Industrial Safety Agency (NISA).

“There could be other similar cracks in the area, and we must find them as quickly as possible.”  Mr Nishiyama added.

TEPCO  is planning to pour concrete into the duct in an attempt to stop the leak, a company spokesman was quoted as saying.

The US Energy Secretary, Steven Chu, estimated on Friday that about 70% of one reactor core and 30% of another were severely damaged. However, these figures have not been confirmed by TEPCO.

What is a lethal dose of radiation from a single Exposure?

Studies of the 1945 atomic bombing at Hiroshima and Nagasaki show that 100 percent of victims whose bodies were exposed to 600,000 millirems (6,000 mSv) died from radiation. About 50 percent of victims who received  450,000 millirems (4,500 mSv) of radiation also died.

(Note: Rem is a unit of ionizing radiation equal to the amount that produces the same damage to humans as one roentgen of high-voltage x-rays.  Source: MIT)

1 rem = 10 mSv  (1 Sv = 100 rem)

Background Radiation in millirems per year (mrem/yr)

• Average background radiation (US):  300
• Higher altitudes (eg. Denver): 400

“Safe Levels” of Radiation (U.S.)

Limits above natural background radiation levels (average 300 millirems per year) and medical radiation:

• Occupation Limit: Maximum of 5,000  (the limit for a worker using radiation)
• Average Natural Background: 300

[Note: Lifetime cumulative exposure should be limited to a person’s age multiplied by 1,000 millirems, e.g., a 70-year-old person, 70,000 millirems.]

Adults

• Max single dose for an adult: 3,000
• Annual total dose: 5,000

Under 18

• Max single dose for a person aged under 18 years: 300 millirems (whole body equivalent)
• Annual total exposure: 500

Fetal Exposure

• Maximum limit for fetal exposure during gestation period:  50 millirems per month above background levels

Medical

• Single Chest X-ray (the whole body equivalent): 2 millirem

Air Travel

• Coast-to-coast US round trip flight: 12 millirems

Megaquake and Tsunami Death Toll

The latest figures released by the authorities put the number of dead at about  12,000 with 16,000 people still listed as missing.

Related Links

• Japan Nuclear Disaster Update – Apr 1

• Japan Nuclear Disaster Update – March 31
• Fukushima Nuclear Disaster Update – March 30
• Tokyo Water Radiation “TOO HIGH” for Infants
• FUKUSHIMA NPP: No 4 REACTOR ON FIRE, NEW EXPLOSION ROCKS No 2

• M6.4 Shock Strikes Off Fukushima Coast
• TOKYO AREA QUAKE WARNING
  Large Earthquake Could Strike Tokyo Area – Megaqauke measuring up to 9.2Mw could strike Tokyo / Chiba Area:  FIRE-EARTH Forecast

• FIRE-EARTH Forecasts: Japan Earthquakes
  As Many as 4 Large Earthquakes [Megaquakes measuring ≥8.0] Could  Strike Japan Region by 2015

• M6.5 Aftershock Strikes Offshore Miyagi
• Significant Seismicity in Tohoku Region, Japan
• Japan Earthquakes: FIRE-EARTH Forecasts and Recent History

Japan Nuclear Disaster Update – Apr 1

Radioactive material probably leaking continuously from Fukushima NPP: NISA

Japan’s nuclear and industrial safety agency (NISA) has warned that radioactive substances from the stricken nuclear power plant may be continuously leaking into the sea.

Frame grab from a video released by TEPCO showing the state of one of the reactors.

An act of sheer folly

“I am prepared for a long-term battle over the Fukushima nuclear plant and to win this battle,” Japan’s Prime Minister Naoto Kan said in a national telecast today.

Battle? What battle? Battle against the ultimate act of human folly? Building a nuclear power plant in an earthquake zone and hoping that the worst won’t happen?

“We cannot say that the plant has been sufficiently stabilized. But we are preparing for all kinds of situations and I am convinced that the plant can be stabilized,” Kan added.

WE keep our fingers crossed. But what about the other nuclear power plants in Japan? Aren’t they equally vulnerable to geophysical phenomena?

“We are focusing on stabilizing the conditions there using every bit of expertise available,” he said. “I am convinced we will be able to achieve it. I do not know for now how long this will take.”

Perhaps, as long as Chernobyl!

The French Connection

The French president has called for new global nuclear rules and offered to host a global conference in France. His concern amid the deepening nuclear disaster at Fukushima NPP indicates that:

1. “Old global nuclear rules” don’t work!
2. France, the most nuclear-dependent country, is also one of the worst nuclear-accident prone countries. [Why ales wold they need “new rules”?]
3. Mr Sarcozy is very afraid that further deepening of Fukushima nuclear disaster may mobilize the French against [at least the expansion of] nuclear industry in France, thus upsetting the nuclear mafia.

Note: France relies on nuclear power for about 80 percent of its electricity and is a major exporter of nuclear technology.

Summary of other developments at Fukushima

• The level of radioactive iodine-131 detected in seawater near the plant on Thursday was 4,385 times the safety limit.
• Radiation level detected in a tunnel outside reactor 2 was higher than 10,000 times the normal levels, NHK reported.
• Up to 75,000 people have been evacuated from the 20-km exclusion zone around the plant and about 140,000 others who live in a 10-km zone beyond that have been advised to leave or to stay indoors.
• The ban on the shipment of foodstuffs from the prefectures affected by radiation contamination has been widened to include beef, Japan’s health ministry said.
• More handheld Gieger counters have been sold in/shipped to Japan in the past three weeks than in the previous 25 years.
• TEPCO has reported a shortage of radiation monitors for workers. They have assigned one per group of workers, instead of one for each worker.
• The recovery of many bodies within the 20-km exclusion zone has been delayed because of the contamination risks.

Related Links

• Japan Nuclear Disaster Update – March 31
• Fukushima Nuclear Disaster Update – March 30
• Tokyo Water Radiation “TOO HIGH” for Infants
• FUKUSHIMA NPP: No 4 REACTOR ON FIRE, NEW EXPLOSION ROCKS No 2

• M6.4 Shock Strikes Off Fukushima Coast
• TOKYO AREA QUAKE WARNING
  Large Earthquake Could Strike Tokyo Area – Megaqauke measuring up to 9.2Mw could strike Tokyo / Chiba Area:  FIRE-EARTH Forecast

• FIRE-EARTH Forecasts: Japan Earthquakes
  As Many as 4 Large Earthquakes [Megaquakes measuring ≥8.0] Could  Strike Japan Region by 2015

• M6.5 Aftershock Strikes Offshore Miyagi
• Significant Seismicity in Tohoku Region, Japan
• Japan Earthquakes: FIRE-EARTH Forecasts and Recent History