We are exerting our utmost effort in establishing the stable cooling of
Reactors and Spent Fuel Pools and contain release of radioactive
substances at Fukushima Daiichi Nuclear Power Station. As for Unit 2, by
cooling the Spent Fuel Pool by the circulating cooling system, we have
reduced evaporation from the Spent Fuel Pool and are reducing the density
of radioactive substances released from the building.
As to the Reactor of Unit 2, we are considering several measures for
stabilization. As one of the efforts, we are adjusting the volume of water
injection monitoring the fluctuation of several parameters. In order to
solidify these efforts, we have to install and calibrate Reactor water
level gauge, install a circulating cooling system, and set up piping for
nitrogen charge to the Reactor Containment Vessel. To do these, we have to
improve the working environment in the Reactor Building for workers.
In preparation for that improvement, we have been measuring the radiation
dose, the density of radioactive substances, humidity etc. in the Reactor
Building of Unit 2. The figures we measured on June 4 were, the total
density of radioactive substances of 1.6 x 10-1 Bq/cm3 and the humidity of
99.9%.
While the density of radioactive substances is of similar level as the
target for Unit 1 in improving the working environment by the an ambient
air filtration system (2.4 x 10-1 Bq/cm3), we will install the ambient air
filtration system to Unit 2 also, and circulate air inside of the building
in order to reduce the density further.
After that, we will open the airlock of the Reactor Building in order for
workers to enter the building and undertake necessary work. In doing so,
we will measure the density of radioactive substances inside the building
to confirm that the impact to the outside is sufficiently low.
As for the humidity inside the building, the building will be ventilated
when we open the airlock thus will become lower.
We will make announcement before we actually open the airlock of the
Reactor Building. At the same time, we will carefully monitor figures at
monitoring posts and announce those figures.
(previously announced on June 8th)
In relation to this matter, today, we, TEPCO have received order* from the
Minister of Economy, Trade and Industry to submit reports related to
improvements to work environment inside the Reactor Building of Unit 2 at
Fukushima Daiichi Nuclear Power Station with regards to the details of the
work, evaluation of the impact of radioactive substance to the outside
environment and radiation management plan of the workers.
*Regarding the Collection of Reports Related to the Improvement of the
Work Environment inside the Reactor Building of Unit 2 at Fukushima
Dai-ichi Nuclear Power Station
06.06.2011 N No.3
June 8, 2011
In order to verify the validness of the emergency measures under Article
64, Paragraph 1 of the Act on the Regulation of Nuclear Source Materials,
Nuclear Fuel Materials and Reactors (1957, Act No. 166), the Ministry
orders your company to, to submit a report regarding the below-specified
items by June 15, 2011, pursuant to the provisions of Article 67,
Paragraph 1 of the same act.
If there are grievances regarding this action, pursuant to the provisions
of Article 6 of the Administrative Appeal Act (Act No. 160 of 1962), an
administrative appeal may be made, in writing, to the Minister of Economy,
Trade and Industry within 60 days from the date one day after the day on
which your company became aware of the fact that this disposition was made.
However, no administrative appeals may be made when a period of one year
has elapsed from the date one day after the date of this disposition, even
if it is within 60 days from the date one day after the day on which your
company became aware of the fact that this disposition was made.
Following the decision regarding the aforementioned objection, an action
for the revocation of this disposition may be filed against the State
(represented by the Minister of Justice) as defendant, within six months
from the date one day after the day on which your company became aware of
the fact that a decision was made in response to the aforementioned
administrative appeal, pursuant to the provisions of Administrative Case
Litigation Act (Act No. 139 of 1962). However, no action for the
revocation of the disposition may be filed when a period of one year has
elapsed from the date one day after the day on which the decision on the
administrative appeal was made, even if it is within six months from the
date one day after the day on which your company became aware of the fact
that the decision on the administrative appeal was made.
Furthermore, an action for the revocation of the original administrative
disposition may be filed without obtaining a decision on an administrative
appeal, if the case falls under any of the following 1 to 3: 1. where no
decision is made even after a period of three months has elapsed from the
date one day after the day on which an administrative appeal was made; 2.
where there is an urgent necessity in order to avoid any considerable
damage that would be caused by the original administrative disposition,
the execution of the original administrative disposition or the
continuation of any subsequent procedure; 3. where there are other
justifiable grounds not to obtain a decision on an administrative appeal.
Required Items
Following items related to the improvement of the work environment inside
the reactor building of Unit 2 at Fukushima Dai-ichi Nuclear Power Station
(NPS)
1.Results of evaluation based on whether or not alternative means exist
regarding the operation details related to the ventilation of the
reactor building of Unit 2 at Fukushima Dai-ichi NPS, the operation plan,
as well as their necessity.
2.Results of evaluation for impact on the surrounding environment of the
Fukushima Dai-ichi NPS including the release of radioactive materials
during the operations related to the ventilation of the reactor building
of Unit 2 at Fukushima Dai-ichi NPS as well as the predictions for the
disperse of said radioactive materials.
3.Monitoring method in order to evaluate properly the impact on the
surrounding environment of the Fukushima Dai-ichi NPS when the
radioactive materials are released if the operations in 2. are executed.
4.Method for managing workers' exposure for the construction, etc. to be
executed after the ventilation of the reactor building of Unit 2 at
Fukushima Dai-ichi NPS
(Translation by NISA; http://www.nisa.meti.go.jp/english/press/2011/06/
en20110609-5.pdf)