On June 3rd, 2011, we have received an instruction document*1 from 
Nuclear and Industrial Safety Agency (NISA) of Ministry of Economy,
 Trade and Industry, in relation to a fact that some damages have 
been found in cylinder liners*2 of emergency diesel generators 
of "Monju", a fast-breeder reactor, of Japan Atomic Energy Agency 
(independent administrative agency). They instructed us to make a 
roadmap as to check of the soundness of cylinder liners which no 
procedural manual was prepared for its re-assembling / dismantling, 
or which we have not carried out in a appropriate manner to prevent 
form being damaged at Units 2 and 4 of Fukushima Daini Nuclear Power 
Station, where the emergency diesel generators of the same 
configuration as the one in "Monju" are used.

We have also received another instruction document*3 that instructs 
to make a roadmap and steadily pursue it, as to check of the 
soundness of cylinder liners and how we will replace them at Unit 2 
of Fukushima Daiichi Nuclear Power Station. For some lead elements 
might have been mixed into the cylinder liners at the plant as is the 
case in "Monju". (Previously announced on June 3, 2011)

Today, we completed and submitted a report to NISA according to the 
requirements they had asked for us. The outline of the report is as 
follows:

1. Soundness of how to inspect the cylinder liners of emergency 
diesel generators
-With regards to the Units 2 and 4 of Fukushima Daini Nuclear Power 
Station, the instruction manual describes how to re-assemble the 
cylinder of emergency diesel generators, but doesn’t how to 
dismantle it. Hence, we have specified the dismantling procedure in 
our manual.
-We evaluated the cylinder liners at Units 2 and 4 of Fukushima Daini 
as sound, because we found nothing wrong with our work management, by 
reviewing manufacturers’ documents or by interviewing concerned 
people when inspections were made. In order to validate, however, we 
will first dismantle the major cylinder liners so that we will 
confirm their soundness. As for other cylinder liners, we will 
evaluate the soundness ahead of schedule in a sequential manner.
- For securing the reliability of power source, we will focus on 
restoring the 3 emergency diesel generators at Unit 1 of Fukushima 
Daini Nuclear Power Station that lost functions due to the Tohoku-
Chihou-Taiheiyou-Oki Earthquake that occurred on March 11, 2011. It 
is after recovering their functions that we will overhaul them as 
soon as we are ready.

2. Soundness of the materials for the cylinder liners of emergency 
diesel generators
- Regarding the emergency diesel generators (A) at Unit 2 of 
Fukushima Daiichi Nuclear Power Station that lost function due to the 
Tohoku-Chihou-Taiheiyou-Oki Earthquake that occurred on March 11, 
2011, we don’t have a restoration plan at the moment. Regarding the 
4 cylinder liners that might have material defects, we will re-
evaluate their soundness or replace them for the sound ones, if we 
will resume the diesel generator,

*1 Instruction document

"Check considering the damage found in cylinder liners of emergency 
diesel generators of "Monju", a fast-breeder reactor, of Japan Atomic 
Energy Agency (independent administrative institution) (instruction)

On June 3rd, 2011, Nuclear and Industrial Safety Agency (NISA) 
received a report from Japan Atomic Energy Agency (independent 
administrative institution) on causes and countermeasures with regard 
to the damage found in cylinder liners of emergency diesel generators 
of "Monju", a fast-breeder reactor.
In the report, they assume that cylinder liners were damaged because, 
when they were dismantled and reassembled, workers used only 
hydraulic jacks with no hydraulic oil gauge and pressured too much.
In Unit 2 and Unit 4 of Fukushima Daini Nuclear Power Station, 
emergency diesel generators of the same configuration as the ones of 
Monju are used, and, as procedures of dismantling and reassembling 
the cylinder liners are not clear, in order to prevent the cylinder 
liners from being damaged, we hereby instruct you to report the 
results of the following 5 items. The due dates of each report are: 
No.1 and No.2---by July 4th, No.3---soon right after implementation, 
No.4---soon after implementation together with No.3, and No.5---soon 
after implementation.

1. Checking and formulating procedures with regard to dismantling 
and reassembling cylinder liners as well as appropriate 
conservation manner of hydraulic pressures
2. Making a roadmap with regard to checking the soundness of the 
cylinder liners that might have been damaged due to inappropriate 
dismantling and reassembling
3. Implementing the roadmap mentioned above in 2.
4. Making a roadmap with regard to exchanging the cylinder liners 
which are not judged as sound in the course of the implementation of 
the checking mentioned above in 3
5.Implementing steadily the roadmap mentioned above in 4.

*2 Cylinder liner
A cylindrical material installed inside the cylinder of a diesel 
engine, forming sliding surfaces with the piston and piston ring. 

*3 Instruction document 

"Check considering the damage found in cylinder liners of emergency 
diesel generators of "Monju", a fast-breeder reactor, of Japan Atomic 
Energy Agency (independent administrative institution) (instruction)

On June 3rd, 2011, Nuclear and Industrial Safety Agency (NISA) 
received a report from Japan Atomic Energy Agency (independent 
administrative institution) on causes and countermeasures with regard 
to the damage found in cylinder liners of emergency diesel generators 
of "Monju", a fast-breeder reactor.
The report says that during the manufacture of cylinder liners, some 
lead was mixed in their materials and a lead structure 
(Widmannstaetten structure), which may weaken the intensity, has been 
formed in them. It also says that the cylinder liners which lead 
might have been mixed in were manufactured from February 1987 to May 
1989.
As in Unit 2 of Fukushima Daiichi Nuclear Power Station emergency 
diesel generators that use cylinder liners which some lead might have 
been mixed in like ones of Monju are used, in order to prevent the 
cylinder liners from being damaged, we hereby instruct you to 
implement the following items and to report the results to us. The 
due dates are: No.1---by No.2---July 4th, No.3---soon after the 
implementation.

1. Checking the soundness of the cylinder which are manufactured from 
February 1987 to May 1989 and lead might have been mixed in.
2. Making a roadmap with regard to exchanging cylinder liners which 
are not judged as sound in the checking process in No.1
3. Implementing the roadmap steadily mentioned above in No.2.