RE: [sc] Some details about Japan Nuclear reactors



RE: [sc] Some details about Japan Nuclear reactors

From: Steve Hartley <steve.hartley_at_xxxxxx>
Date: Mon, 21 Mar 2011 12:30:47 -0000
Message-ID: <853A00454480354391301CE4C637F999014AFE41@xxxxxx>
This is my first post.  Although distance from earthquake epicentres is
a major factor to degree of land shift, it is not always the case that
the closer you are the more damage results.  A more important factor is
the type of soil on which a building is resting. Sandy soils that are
water saturated are the most dangerous, since they amplify surface
movement, while solid rock is the safest.  I think one would need to
know if any underlying influences existed before a direct comparison
with reactor design is discussed.

Regards, 

Steve Hartley
Senior Functional Safety Engineer 

MIRA Ltd
Watling Street, Nuneaton
Warwickshire CV10 0TU, UK

Direct Tel: +44 (0)24 7635 5491 
Direct Fax: +44 (0)24 7635 8491  
Email: steve.hartley@xxxxxx 

http://www.mira.co.uk
-----Original Message-----
From: safety-critical-request@xxxxxx
[mailto:safety-critical-request@xxxxxx] On Behalf Of Nicholas Mc
Guire
Sent: 21 March 2011 12:06
To: safety-critical@xxxxxx
Subject: Re: [sc] Some details about Japan Nuclear reactors

On Mon, 21 Mar 2011, Peter Bishop wrote:

> One interesting fact that does not appear to have been given any 
> prominence is that other Japanese nuclear plant survived much better
>
> The Onagawa nuclear plant (3 reactors) was closer to the earthquake 
> epicentre than Fukushima
>
> - about half the distance in fact, so it should have suffered more 
> seismic disturbance and a bigger tsunami.
>
> Perhaps we should be asking what Onagawa did right?
>
while that is a legitimate question - it also is important to note that
this is not a sufficiently simply causal relation to imply that being
closer to the epicenter automatically means more damage. Also the
reports indicate that the earthquake was not the decisive factor for
Fukoshima but rather the tsunami (which took out the generators) and the
effective impact of a tsunami also has a high dependency on local
effects. Last if you look at the list of incidences in Onagawa - it also
does not necessarily raise the confidence in this technology.

Notably the handbook error in 1988 that was not reported until 2007
which would have prevented a similar incident in 1999 in Shika is a good
example of this not being problems that have technological mitigations.

I would be very interested in hearing how members of this list expect
that the organisational issues involved in this high-complexity
technology can be handled in a way to achieve acceptable residual risk -
the past 50 years of nuclear power - while seing dramatic improvements
of technology - have not been able to answer this question in any way
(and I might add the still open issue of a permanent repository for
nuclear waste)

hofrat


--
MIRA Ltd

Watling Street, Nuneaton, Warwickshire, CV10 0TU, England
Registered in England and Wales No. 402570
VAT Registration  GB 100 1464 84

The contents of this e-mail are confidential and are solely for the use of the intended recipient.  If you receive this e-mail in error, please delete it and notify us either by e-mail, telephone or fax.  You should not copy, forward or otherwise disclose the content of the e-mail as this is prohibited.
Received on Mon 21 Mar 2011 - 12:33:05 GMT