Dear Friends,
Please see the following updates on Fukushima Daiichi NPS.(1) IAEA Fact Finding Team’s Visit to Japan
ü Preliminary Summary was reported to Japanese Government.
(2) Plant Status
ü Unit 2 Spent Fuel Pool cooling started.
(3)Results of Nuclide Analysis for Strontium 89/90 in the Coast/Offshore, air and soil of Fukushima Daiichi (Sampled on May 9).
ü No Sr-89/90 detected from the air at West gate of the site.
ü Sr-89/90 were detected from the seawater near the site and the soil in the site. We believe these Sr-89/90 come from the reactors.
Contacts:
TEPCO Washington Office: 202-457-0790
Kenji Matsuo, Director and General Manager
Ikuo Nishimura, Deputy General Manager,
Masayuki Yamamoto, Manager, Nuclear Power Programs
(1) IAEA Fact Finding Team’s Visit to Japan
- IAEA Fact Finding Team investigated TEPCO’s Fukushima Daiichi and Daini NPS on May 26 – 27, and had meetings in Tokyo before and after the site visit.
- The team reported a preliminary summary to the Japanese Government on June 1. The team’s findings are:
Ø Japan’s response to the nuclear accident has been exemplary, particularly illustrated by the dedicated, determined and expert staff working under exceptional circumstances;
Ø Japan’s long-term response, including the evacuation of the area around stricken reactors, has been impressive and well organized. A suitable and timely follow-up programme on public and worker exposures and health monitoring would be beneficial;
Ø The tsunami hazard for several sites was underestimated. Nuclear plant designers and operators should appropriately evaluate and protect against the risks of all natural hazards, and should periodically update those assessments and assessment methodologies;
Ø Nuclear regulatory systems should address extreme events adequately, including their periodic review, and should ensure that regulatory independence and clarity of roles are preserved; and
Ø The Japanese accident demonstrates the value of hardened on-site Emergency Response Centres with adequate provisions for handling all necessary emergency roles, including communications.
- During the visit, TEPCO explained the facts as they were and responded the team’s requests as much as possible. We think it was a very significant visit for us to show what challenges the nuclear power station faced under the unprecedented huge natural disaster and how TEPCO and other organizations collaborated to cope with the accident.
- We sincerely hope our experiences of Fukushima Daiichi and Daini would be shared globally and contribute to improve nuclear safety world wide.
- Please see attached preliminary summary for detail.
(2) Plant Status
Unit 1: 5.0 m3/h (Reduced from 6.0 m3/h at 20:30, May 31)Reactor pressure vessel temperature (as of 11:00, June 1):
Unit 2: 4.0 m3/h (No change since May 30)Reactor pressure vessel temperature (as of 11:00, June 1):
Unit 3: 11.5 m3/h (Reduced from 12.5 m3/ at 10:10, June 1)Reactor pressure vessel temperature(as of 11:00, June 1):
136.4 C - May 31, 17:21 Started operation (SFP temperature 68 C at 18:25)
18:11 Rated flow rate 100 m3/h- June 1, 1:47 Flow rate adjusted 80 m3/h
5:00 SFP temperature 64 C 6:06 – 6:53 Fresh water injection through FPC (25 m3) 16:00 SFP temperature 48.4 C - Test run was suspended due to insulation degradation in power supply cable.
- We will repair the cable on June 2. Then we will make a test-run.
(3) Results of Strontium Measurement
- Seawater: After about one month since the previous sampling, strontium seems to dilute to the ocean and measured radioactivity results show decreasing trend.
- Soil: Overall, the value was the same level as the previous sampling. Yachouno Mori shows higher than the previous data because of the difference in depth of sampling, this time the sample was taken from the surface. There seems no indication of new accumulation of strontium in the soil.
- Air: No strontium was detected as was the previous time. This result suggest no release/diffusion of strontium from the units.
- Sr-89 and Sr-90 were detected at both coast and offshore. It is conceivable that this is due to the accident. However, results are below density limit in the water by the announcement of Reactor Regulation.
< Result of Strontium analysis result in the soil>
Sampling spot (): Distance from the stack of Unit 1, 2 | Sr-89 (Sampling Date) | Sr-90 (Sampling Date) | ||
This time (5/9) | Previous (4/18) | This time (5/9) | Previous (4/18) | |
(1) Ground (WNW 500m) | (2.8±0.01) x 103 | (2.9±0.01)×103 | (4.8±0.05) x 102 | (4.0±0.05)×102 |
(2) Yachouno Mori (W 500m) | (1.9±0.01) x 103 | (2.3±0.12)×101 | (3.4±0.04) x 102 | (3.4±0.49) |
(3) Around Industrial Waste Treatment Area (SSW 500m) | (1.7±0.01) x 103 | (4.4±0.02)×103 | (3.0±0.05) x 102 | (5.7±0.06)×102 |
Range of past analysis* | - | ND ～ 4.3 | ||
* 2009 Report result of radiation measurement of surrounding area of nuclear power station (1999 to 2008)
- The density of Sr-90 was higher than the fallout detected in Japan for the past nuclear test in the atmosphere, we consider this strontium is attributed to the nuclear accident this time.
1. Sampling spot：West gate of Fukushima Daiichi Nuclear Power Station
2. Analyses organization：Japan Chemical Analysis Center
（Unit：mBq/m3）
Type of sampling | Date of sampling | Sr-89 | Sr-90 |
Volatile | May 9 | N.D. | N.D. |
Particle | N.D. | N.D. |
- Sr-89 and Sr-90 were not detected from the sample analyzed this time.
- TEPCO English website
- METI(Ministry of Economy Trade and Industry)
- NISA(Nuclear and Industrial Safety Agency)
- JAIF(Japan Atomic Industrial Forum Inc.)
- FEPC(The Federation of Electric Power Companies of Japan)
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