Due to the Tohoku-Chihou-Taiheiyou-Oki Earthquake which occurred on March
11, 2011, TEPCO's facilities including our nuclear power stations have been
severely damaged. We deeply apologize for the anxiety and inconvenience
caused.
With regard to the accident at Fukushima Daiichi Nuclear Power Station, on
April 17, 2011, we have compiled the roadmap towards restoration from the
accident and on July 19 we accomplished the Step1 target "Radiation dose
is in steady decline". Then on December 16 we confirmed the accomplishment
of the Step 2 target "Release of radioactive materials is under control
and radiation doses are being significantly held down".
In addition, on December 21, 2011, we have compiled the "Mid-to-long-Term
Roadmap toward the Decommissioning of Fukushima Daiichi Nuclear Power Units
1-4, TEPCO".
In addition to the maintenance of the plant's stable condition, we will
implement Mid-to-Long Term countermeasures towards the decommissioning of
Fukushima Daiichi Nuclear Power Units 1-4 to enable evacuees to return to
their homes as soon as possible and reduce the anxiety of the people in
Fukushima and the whole nation as soon as possible.
Below is the status of TEPCO's major facilities.
* The updates are underlined.
[Nuclear Power Station]
· Fukushima Daiichi Nuclear Power Station: Unit 1 to 3: shut down due to
the earthquake:
(Units 1 to 4: shutdown due to the earthquake)
- At 3:05 pm on January 30, we stopped the operation of the secondary
air-fin coolers (the temperature of fuel pool at the time of stoppage:
12°C) of spent fuel pool in order to prevent overcooling of alternative
cooling system of spent fuel pool of Unit 1.
- At 4:27 pm on January 29, we stopped the operation of the secondary
air-fin coolers (the temperature of fuel pool at the time of stoppage:
21°C) of spent fuel pool in order to prevent overcooling of alternative
cooling system of spent fuel pool of Unit 4. At 3:13 pm on January 30,
we restarted the operation of the air-fin cooler. (the temperature of
fuel pool at the time of restart: 29°C)
- At 4:05 pm on January 30, we started to transfer the accumulated water
from the basement of T/B, Unit 2 to the Centralized Waste Treatment
Facility (Miscellaneous Solid Waste Volume Reduction Treatment Building
[High Temperature Incinerator Building] and Process Main Building)
through newly installed polyethylene pipes.
- At 4:12 pm on January 30, we started to transfer the accumulated water
from the basement of T/B, Unit 3 to the Centralized Waste Treatment
Facility (Miscellaneous Solid Waste Volume Reduction Treatment Building
[High Temperature Incinerator Building] and Process Main Building)
through newly installed polyethylene pipes.
- On January 30, we conducted night patrol due to water leakage that was
thought to be due to freezing. At 10:50 pm on the same day, we found
something that looked like crack that was thought to be due to freezing
at valve box of filtrate water side piping at the entrance of the
reactor water injection pump (C) on the hill. The surface water of
this point has been freezing and we found no water leakage. From this
time, we will review the implementation of valve replacement and
measure against freezing.
· The water leakage newly found from the previous release (as of 10:00
am on January 30) was as follows;
○Valve box of filtrate water side piping at the entrance of the reactor
water injection pump
(C)on the hill. (Found at around 3:15 pm on January 30)
(Filtrate water*: the width is equivalent to approx. 2 pencils)
○The exit line flange of seal water cooler of evaporative concentration
apparatus 3A
(Found at around 3:20 pm on January 30)
(Filtrate water*: 2 drops per approx. 1 second)
○The condensed water return line flange of evaporative concentration
apparatus (A)
(Found at around 9:05 am on January 31)
(Filtrate water*: approx. 20 L)
*Filtrate water: water taken from the barrage
- At 3:50 pm on January 30, since we completed the replacement of water
injection line of water injection pump on the hill with polyethylene
pipes following the reliability improvement of water injection to the
reactors, we have adjusted the amount of water injection to the reactor
of Unit 1 through water feeding system from approx. 6.5m3/h to approx.
5.5 m3/h and that through Core Spray System from approx. 0 m3/h to
approx 1.0 m3/h.
- At 10:15 pm on January 30, since the decrease of water injection rate
was confirmed, we adjusted the amount of water injection to the reactor
of Unit 1 through core spray system from approx.0.5 m3/h to approx.1.0
m3/h. (Continuing water injection from feeding water system at approx.
5.8 m3/h.)
- At 9:35 am on January 31, we started transfer of accumulated water from
site banker to process main building in the centralized radiation waste
treatment facility.
- At 10:00 am on January 31, we started transfer of accumulated water
from the basement of turbine building of Unit 6 to the temporary tanks.
- Because of the finding of accumulated water included radioactive
materials at the trench between the process main building and the
miscellaneous solid waste volume reduction treatment building [high
temperature incinerator building](December 18, 2011), we started the
inspection of other trenches at the site on January 11.
As a result of the inspection of January 30, the locations where
accumulated water was discovered and the nuclide analysis results are
as follows:
· Unit 2 Transformer trench for disaster prevention
I-131:below measurable limit, Cs-134:approx. 2.1x100Bq/cm3,
Cs-137:approx. 3.0x100Bq/cm3
· Fukushima Daini Nuclear Power Station:
(Units 1 to 4: shutdown due to the earthquake)
· Kashiwazaki Kariwa Nuclear Power Station: Units 6: under normal operation
(Units 1 to 5 and 7: outage due to regular inspections) [Thermal Power Station]
· Power supply has returned to normal and facilities damaged by the
earthquake are now being handled in a timely manner.
[Hydro Power Station]
· Power supply has returned to normal and facilities damaged by the
earthquake are now being handled in a timely manner.
[Impacts on Transmission Facilities]
· Power supply has returned to normal and facilities damaged by the
earthquake are now being handled in a timely manner.
[Impacts on Power Supply and Demand Balance]
This winter, there are some minus factors such as the regular inspection
of Unit 5 at Kashiwazaki-Kariwa Nuclear Power Station*. On the other hand,
there are several plus factors such as the recovery of the common thermal
power stations which suffered the earthquake. As a result, we expect to
secure 54.6 GW (at the end of January), 53.7 GW (at the end of February)
supply power.
Compared to the maximum demand in the last winter, which is 51.5 GW, we
will have 2.2 - 3.1 GW generation reserve margin.
We expect to maintain stable power supply this winter, however, as there
remains possibilities of unplanned shutdowns at our power stations and
growth in the demand according to the rapid change in the temperature, we
would like to ask your reasonable effort to save electricity.
We will continue to make our efforts to maintain stable operation and
maintenance of the power facilities in order to "prevent in principle" the
planned blackouts and secure power supply.
* Correction of Description in [Impacts on Power Supply and Demand Balance]
We described,"there will be some minus factors such as the regular
inspection of Unit 5 at Kashiwazaki-Kariwa Nuclear Power Station" in the
previous press release. However, because Unit 5 of Kashiwazaki-Kariwa
Nuclear Power Station has already conducted a regular inspection since
January 25, we revise the previous sentence to "there are some minus
factors such as the regular inspection of Unit 5 at Kashiwazaki-Kariwa
Nuclear Power Station". We would like to apologize for the correction
(February 8, 2012).
Appendix: Past Progress (As of 10:00 am, January 31, 2012) (PDF 390KB)
Appendix: Past Progress (From March 11, 2011 to July 31, 2011) (PDF 225KB)
* Revised past progress
