Despite the deafening silence from TEPCO regarding questions over a physical breech in Reactor 2, it is now generally being considered that there is a breech in reactor 2. It is not clear if it is a hole in the containment vessel of some kind or just some disconnected or cracked pipes. Experts are estimating the percent of fuel in the reactors that were active at the time of the quake that has been damaged as fairly high (over half). The most significant news over the last several hours is probably the identification of a major route by which radioactive water is leaking from Reactor 2 into the sea. This is a 20 cm wide crack in the concrete foundation of the reactor building. TEPCO claims that it will fill the crack with concrete.
It also appears that there are raised concerns about hydrogen buildup in reactors 1 and 2, and efforts are being made to avoid an explosion from this hydrogen.
We have not heard a lot about Reactors 5 and 6 because they were not in operation at the time of the earthquake and tsunami, so the situation has not been particularly tricky there, but there is a development there now. Both buildings have spent fuel pools and though the cooling systems there are said to be working there is concern over the ability to keep these fuel rods cool over the short to medium term future. If they heat up it is possible to get hydrogen buildup which could cause an explosion in the building containing the reactors. To avoid this, holes have been punched in the structures covering reactors 5 and 6.
Some experts assert that the chance of fuel undergoing significant fission beyond what is happening now, which might damage containment vessels and cause more radiation escape, as non-trivial in the short to medium term future.
April 1, 8PM
Three of the six reactors at the Fukushima Daiichi nuclear power plant experienced a jolt stronger than a worst case projection when hit by Japan’s largest-ever earthquake March 11, provisional data by the operator Tokyo Electric Power Co. showed Friday. -kyodo news
- The data suggest that the intensity of the strongest earthquake projected could have been underestimated. The nuclear safety agency stopped short of describing the finding as a problem but urged the utility to analyze it in detail. -kyodo
April 2, 3 AM
“A Japanese government official told Kyodo News it has been confirmed that water with high levels of radiation has seeped into the sea from the No. 2 reactor…” (Efforts to remove tainted water continue…)
Checking if tainted water from other reactors seeping into sea -kyodo news
”Tokyo Electric Power Company says it has found that radioactive water is leaking into the ocean from a 20-centimeter crack in a facility wall of the No.2 reactor at the Fukushima Daiichi nuclear power plant.
The power company said on Satur…day that the level of radiation has been measured at over 1,000 millisieverts per hour.” (NHK)
“The Joint FAO/IAEA Food Safety Assessment Team has completed its mission and presented its report to the Japanese Cabinet Office, Ministry of Foreign Affairs, Ministry of Health, Labour and Welfare and the Ministry of
Agriculture, Fisheries and Forestry on 31 March. The IAEA members of the Team are returning to Vienna today.” -from IAEA update for April 1
TEPCO says it will make radiation levels available on its website. -NHK
SDF aircraft used in the operations around the plant have become highly contaminated – cesium adheres to the paint. The gov. is looking into the purchase of special equipment for decontamination, and is advising mechanics to take precautions. -NHK
News stories and updates:
A crack in the foundation of the Fukushima-1 nuclear power plant’s second reactor is being entombed in concrete to prevent radioactive water from flowing out into the sea.
According to estimates, radiation levels in the area are almost 5,000 times above normal.
Russian nuclear energy expert Natalia Mironova says that Fukushima disaster is “much bigger than Chernobyl.”
the Russian nuclear energy expert has assessed that Japan’s unfolding nuclear disaster is “much bigger than Chernobyl” and could rewrite the international scale used to measure the severity of atomic accidents.
“Chernobyl was a dirty bomb explosion. The next dirty bomb is Fukushima and it will cost much more” in economic and human terms, Mironova was cited by the agencies.
Mironova is a thermodynamic engineer who became a leading anti-nuclear activist in Russia in the wake of the accident at the Soviet-built reactor in Ukraine in 1986.
For decades we have been told that with the lessons learned from the 1986 Chernobyl disaster, nuclear energy is safe. As the still unfolding mayhem at the Dai-Ichi plant in Fukushima, Japan, proves, nothing could be further from the truth.
Only two U.S. nuclear sites are in compliance with federal fire regulations. How confident can we be that the Nuclear Regulatory Commission has things firmly in hand?
At the damaged Fukushima complex, officials say radioactive water is leaking into the ocean, but it is expected to be quickly diluted. Japan’s Kan visits a tsunami-stricken town.
The authorities reassure us by saying there is no immediate danger and a few absolutist environmentalists obsessed with nuclear power because of the urgency to limit emissions repeat the industry mantra that only a few people died at Chernobyl – the worst nuclear accident in history. Those who disagree are smeared and put in the same camp as climate change deniers.
I prefer the words of Alexey Yablokov, member of the Russian academy of sciences, and adviser to President Gorbachev at the time of Chernobyl: “When you hear ‘no immediate danger’ [from nuclear radiation] then you should run away as far and as fast as you can.”
Current International Atomic Energy Agency briefing:
On Saturday, 2 April 2011, the IAEA provided the following information on the current status of nuclear safety in Japan:
Overall at the Fukushima Daiichi plant, the situation remains very serious.
In preparation for transferring water in the basement of the Unit 1 turbine building to the condenser, water in the condenser storage tank is being transferred to surge tank of the suppression pool since 31 March 03:00 UTC. Water in the trench was transferred to a water tank at the central environmental facility main building. The water level in the trench was reduced by 1 metre to 1.14 metre below the top of the trench on 31 March. On Unit 2 in order to prepare for removal of the water from turbine building basement, pumping of water from the condenser to suppression pool water surge was started 29 March 07:45 UTC and was finished 1 April 02:50 UTC. On Unit 3 in order to prepare for removal of the water from turbine building basement, pumping of water from the condenser to suppression pool water surge was started 28 March 08:40 UTC and completed 30 March 23:37 UTC.
In a press release on the 2nd April NISA reported the following. Water with dose rate of greater than 1000 millisievert/hr was confirmed by TEPCO at around 00:30 UTC on 2nd April in a pit housing cables located next to the Unit 2 sea water inlet point. There exists a crack on the sidewall of the pit, about 20cm in length, and water inside the pit is confirmed to be leaking directly to the sea. The isotopic analysis of water samples from inside the pit, the sea and near the seawater inlet bar screen filter is in process. Currently a plan to patch the pit with concrete is underway to stop the leakage. An investigation on the leakage path to this pit is on-going and measures to stop leakage to the sea will be implemented.
Transfer of fresh water from a US Navy barge to the ‘filtered water tank’ started on 1 April 06:58 UTC, and was suspended on 1 April 07:25 UTC due to a connection failure. A second US Navy barge left Onahama port and planned to arrive 2 April 00:30 UTC.
On Unit 1 fresh water has been continuously injected into the reactor pressure vessel through the feed-water line at an indicated flow rate of 8 m3/h using a temporary electric pump with diesel backup. The indicated temperature at the feed water nozzle of the RPV has decreased from 256 °C to 249 °C and at the bottom of RPV decreased from 128 °C to 119 °C. There was a corresponding decrease in RPV pressure and Drywell pressure.
Fresh water is injected continuously through fire extinguisher line on Unit 2 at an indicated rate of 9 m3/h using a temporary electric pump with diesel backup. The indicated temperature at the feed water nozzle of the RPV has decreased from 165 °C to 161 °C. The temperature at the bottom of RPV was not reported. Indicated Drywell pressure remains at atmospheric pressure.
On Unit 3 Fresh water is being injected continuously at an indicated rate of 7 m3/h into the reactor core through the fire extinguisher line using a temporary electric pump with diesel backup. The indicated temperature at the feed water nozzle of the RPV is about 119 °C and at the bottom of RPV is about 90 °C.
Fresh water (90 T) was pumped into the spent fuel pool in Unit 1 using a concrete pumping truck on 31 March. In Unit 2, injection of water into spent fuel pond using the temporary pump was restarted on 1 April 05:56 UTC. Fresh water (180 T) was pumped into the spent fuel pool on Unit 4 using a concrete pumping truck on 1 April.
Units 5 and 6 remain in cold shutdown with plant systems operating on off-site AC power.
2. Radiation Monitoring
On 1 April, deposition of iodine-131 was detected in 7 prefectures ranging from 7 to 74 becquerel per square metre. Deposition of cesium-137 in 9 prefectures was reported on April 1st ranging from 2.9 to 76 becquerel per square metre. Reported gamma dose rates in the 45 prefectures showed no significant changes compared to yesterday.
The Ministry of Agriculture, Forestry and Fisheries of Japan informed the IAEA that, because of winter conditions, most cattle, pigs and chickens are presently kept indoors. Animals are primarily fed on stored dried grass, silage and grain that has not been contaminated by the releases from the Fukushima Daiichi NPP.
On 31 March, NISA reported that among the workers at the Fukushima Daiichi plant, 21workers have received doses exceeding 100 mSv. No worker has received a dose above 250 mSv, which is the dose limit for emergency workers.
On the 30 March, 180 000 Bq/l of I-131 and 15 000 Bq/l of Cs -137 were detected in the vicinity of the discharge water outlet of Unit 4.
The data reported for 27th – 30th March indicated that the levels at 30 m from the common discharge point of Units 5 and 6 were relatively constant at 45 000 – 55 000 Bq/l for I-131 and 10 000 – 15 000 Bq/l for Cs-137.
In addition to the 8 sampling points 30 km from the coast two additional monitoring stations were added in the South, 10km and 20 km from shore. The values reported for 28 and 30 March indicate a non-uniform distribution and trend.
For more information and essays about the Earthquake, Tsunami and Nuclear Reactor problems in Japan CLICK HERE.