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Proud Mary

Wed Jan 29 2014, 10:30PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

How Citizen Scientists Can Fill in Information Gaps About Fukushima

Proud Mary

Thu Jan 30 2014, 03:29PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Criminal complaint filed over dumping of Fukushima radioactive waste in Shiga The Japan Times

Proud Mary

Thu Jan 30 2014, 03:32PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Hundreds file lawsuit against makers of Fukushima nuclear plant

Patrick

Fri Jan 31 2014, 01:11AM

Registered Member #2431 Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639

the cost of decommissioning and isolation must be included in the operational expense of a privately operated reactor. or this will go on and on.

Proud Mary

Fri Jan 31 2014, 09:07AM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Patrick wrote ...

the cost of decommissioning and isolation must be included in the operational expense of a privately operated reactor. or this will go on and on.

In the UK, private companies have refused to bid for government nuclear operating licenses if they have to pay to pay for decommissioing and clean-up, so the government has set up (and privatized) its own nuclear decommissioning authority.

Here is the past and future of just one of Britain's old magnox power station reactors, one that has never malfunctioned enough to make the news for more than a day or two:

The final decommissioning at Trawsfynydd and elsewhere depends on finding a safe long term solution for where to deposit the ILW as well as the High Level Waste (HLW) currently stored at Sellafield. This includes the spent nuclear fuel which was removed when the plant closed.

Trawsfynydd timeline

1959: Construction started
1965 to 1991: Electricity generation
1993 to 1995: Decommissioning starts â€“ fuel removed and sent to Sellafield
1995 to 2016: Recovery of waste and preparations to put the plant into a â€˜passively safeâ€™ state
2020-26: Reduction in height of reactor buildings
2040s: Scheduled removal of Intermediate Level Waste to deep geological storage
2074: Final site clearance starts
2083: Site returned to pre-existing state

How do you close a nuclear power station? As the UK embarks on building what could be a new generation of nuclear power plants, work continues to decommission the first generation of nuclear power stations at sites including Trawsfynydd in Snowdonia which will take an estimated 90 years to complete.

Robotic recovery: Eryl Pritchard is at the controls of a robotic arm engaged in the painstaking process of retrieving radioactive resin from a dark, water-filled vault. â€œItâ€™s not as simple as it looks,â€ he says. Nothing about it looks simple. Radioactivity inside the vault means everything has to be done remotely using tools mounted on the robotic arm.

A bank of monitors show the arm from various angles. A control panel shows a mind-boggling array of levers, switches and buttonsâ€¦â€¦..

Some of the decommissioning work is considered too dangerous or uneconomic to carry out in the current phase of decommissioning.

The two steel pressure vessels which contained the nuclear reactors are staying in the reactor buildings until the radioactivity of the steel has decayed to a safer level.

The twin reactor buildings are having their height lowered to reduce the visual impact of the plant on the surrounding Snowdonia countryside.

From 2026 that is how the site will be left with the ILW still stored on site alongside the reactor buildings.
Where does the radioactive waste go?

The final decommissioning at Trawsfynydd and elsewhere depends on finding a safe long term solution for where to deposit the ILW as well as the High Level Waste (HLW) currently stored at Sellafield. This includes the spent nuclear fuel which was removed when the plant closed.

The most likely solution is storage deep underground but a site has yet to be identified. It is hoped that will be established by the 2040s allowing the ILW at Trawsfynydd to be removed. Final site clearance at Trawsfynydd is not projected to start until 2074 with the land returned to its original state by 2083. It is at that stage that the reactor buildings and the steel pressure vessels will be demolishedâ€¦â€¦â€¦

Another issue will be what to do with the graphite reactor cores which are still inside the steel pressure vessels at Trawsfynydd.

â€œOne of the problems the UK has with its commercial nuclear power reactors, with the exception of Sizewell B, is that they all have a large graphite core which is used as a moderator, thatâ€™s inside the pressure vessel and thatâ€™s used to slow the neutrons down.

â€œThere is no real disposal route for the graphite in the UK, the volumes are huge. If you look at the carbon, and the sulphur as well, certain isotopes, the half-lifes are hundreds of thousands of years,â€ says Belshaw. While the radioactivity will be very persistent, the graphite is only classed as Low Level Waste (LLW), so will probably not be stored deep underground.
Could the decommissioning be done faster?

Twenty years after it closed, many hundreds more people are employed at Trawsfynydd than when it was generating power. And it will be many decades before the site can be fully restored.

Could it be done more quickly? Not economically says its owners, Magnox. Earlier decommissioning would involve more expensive remote operations and still carry the risk of exposing workers to radiation.

So: nobody knows how all phases of decommissioning can be made to happen, even at an unproblematic reactor like Trawsfynydd in Snowdonia, a reactor that has never leaked enough to become infamous, though female cancer mortality in the immediate area is much higher than the national average, and the sediments in a local lake would be classified as low level nuclear waste if a storage license had ever been sought for them.

An open-ended commitment to meeting decades or centuries of huge costs for industrial processes that have not yet been invented - and perhaps never will be invented, or permitted to be used - is 100% unattractive to private investors, so responsibility for the decommissioning phase of nuclear power generation remains with the public purse.

Proud Mary

Fri Jan 31 2014, 09:34AM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Sellafield nuclear site has 'elevated levels of radioactivity'

Sellafield changed its name from Windscale some years ago, in the hope the public would forget the Windscale Fire disaster of 1957 - a burnt out radioactive ruin whose 'final decommissioning' is not now due to happen for 'forty plus' years - i.e. when the cows come home.

The chimney at the left-hand edge of the picture in this article about the new leak is the Windscale Atomic Pile.

Proud Mary

Fri Jan 31 2014, 01:17PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Debris hinders decommissioning work at Fukushima nuclear plant - AJW by The Asahi Shimbun

Proud Mary

Fri Jan 31 2014, 01:19PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Fukushima Watch: New Technology to Stop Deadly Strontium - Japan Real Time

Proud Mary

Sat Feb 01 2014, 02:20AM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Japanese radio host told to keep silent on Fukushima radiation, resigns

There is no democracy without informed choice.

Uspring

Sat Feb 01 2014, 07:19PM

Registered Member #3988 Joined: Thu Jul 07 2011, 03:25PM
Location:
Posts: 711

Japanese radio host told to keep silent on Fukushima radiation, resigns

That is also quite funny, recommended reading

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