The latest from IAEA, excerpt :
" IAEA Briefing on Fukushima Nuclear Accident (3 May 2011, 19:50 UTC)
On Tuesday, 3 May 2011, the IAEA provided the following information on the current status of nuclear safety in Japan:
1. Current situation
Overall, the situation at the Fukushima Daiichi nuclear power plant remains very serious.
Changes to Fukushima Daiichi plant status
The IAEA receives information from various official sources in Japan through the Japanese national competent authority, the Nuclear and Industrial Safety Agency (NISA). The Update Brief is based on information received by the IAEA Incident and Emergency Centre by 17:00 UTC on 2 May 2011.
Management of on-site contaminated water
According to the 25 April evaluation by NISA of the report submitted by the Tokyo Electric Power Company (TEPCO), there is a little less than 70,000 tonnes of stagnant water with high level radioactivity in the basement of the turbine buildings of Units 1, 2 and 3.
The stagnant water (around 120 m3) in the basement of the turbine building of Unit 6 was transferred to a temporary tank on 1 May. The transfer of stagnant water from the basement of the turbine building of Unit 6 was resumed on 2 May.
Work to block the Unit 2 trench pit was started on 1 May.
Plant status
On 27 April TEPCO provided an update of the estimated percentage of core damage for Units 1, 2 and 3 following an assessment (the values assessed previously which TEPCO had provided on 15 March are given in parentheses): Unit 1: 55% core damage (70%); Unit 2: 35% core damage (30%); Unit 3: 30% core damage (25%). This reflects a revised assessment rather than any recent changes in conditions in the reactor cores.
White smoke continues to be emitted from Unit 2 and Unit 3. There was no more white smoke seen emanating from Unit 4 as of 21:30 UTC on 25 April or from Unit 1 as of 21:30 UTC on 30 April.
In Unit 1 fresh water is being continuously injected into the reactor pressure vessel through the feedwater line at an indicated flow rate of 6 m3/h using a temporary electric pump with off-site power.
In Unit 2 and Unit 3 fresh water is being continuously injected into the reactor pressure vessel through the fire extinguisher line at an indicated rate of 7 m3/h using temporary electric pumps with off-site power.
On 29 April TEPCO checked the status inside the reactor building of Unit 1 using a remotely controlled robot and confirmed that there was no significant leakage of water from the primary containment vessel. Nitrogen gas is still being injected into the containment vessel in Unit 1 to reduce the possibility of hydrogen combustion inside the containment vessel. The indicated pressure in the reactor pressure vessel is still increasing.
In Unit 1, the indicated temperature at the feedwater nozzle of the reactor pressure vessel is 142 ° C and at the bottom of reactor pressure vessel is 106 ° C.
In Unit 2 the indicated temperature at the feedwater nozzle of the reactor pressure vessel is 118 ° C. The reactor pressure vessel and the dry well remain at atmospheric pressure. On 28 April an amount of 43 tonnes of fresh water was injected into the spent fuel pool using the spent fuel pool clean-up system.
In Unit 3 the indicated temperature at the feed water nozzle of the reactor pressure vessel is 99 °C and at the bottom of the reactor pressure vessel is 124 °C. The reactor pressure vessel and the dry well remain at atmospheric pressure.
On 2 May an amount of 55 tonnes of fresh water was injected into the Unit 2 spent fuel pool using the fuel pool clean-up system.
There has been no change in the status in Unit 5 or in the common spent fuel storage facility.
Spraying of anti-scattering agent at the site is continuing. An area of about 1000 m2 on the south side of the turbine building of Unit 4, and an area of about 4400 m2 of the surface on the slope around the former main office building, near the on-site gymnasium and on the west side of the shallow draft quay, were sprayed on 1 May."
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