Fukushima updates - items pertaining to Reactor 4 fuel removal and additional radiation contamination news items. Also note the outbreak of problems at other plants around the globe !

http://fukushima-diary.com/2012/07/reactor4-the-biggest-concern-is-corrosion-to-release-fuel-assemblies-from-channel-box/

[Reactor4] The biggest concern is corrosion to release fuel assemblies from channel box

Posted by Mochizuki on July 19th, 2012 · No Comments

Following up this article..[Reactor4] Photos and videos to take out the new fuel assemblies

Actual Fukushima workers Happy11311 and TS were talking about the risk to take out the rest of fuel assemblies from SFP4 on Twitter.

<Translate>

(TS)

What do you think about the risks to make it difficult to take out the rest of fuel assemblies, such as disfigured rack by explosion or corrosion of channel box etc..

(Happy11311)

There are various risks but disfigured rack or sticking can be managed. The biggest risk is corrosion. The worst senario is fuel assemblies are released from channel box to have channel fastener taken off because of corrosion. There is no contingency plan for it at this moment.

<End>

and......

http://fukushima-diary.com/2012/07/reactor4-taken-fuel-assemblies-were-100-times-more-radioactive-than-normal/

[Reactor4] Taken fuel assemblies were 100 times more radioactive than normal

Posted by Mochizuki on July 19th, 2012 · 1 Comment

Following up this article..[Reactor4] Photos and videos to take out the new fuel assemblies

Actual Fukushima worker Happy11311 commented they measured 2~3 mSv/h from the taken new fuel assemblies of SFP4, which is about 100 times higher than usual.

<Translate>

(Happy11311)

It took 2 days to take out the fuel assemblies from 7/18 to 7/19.  I heard the radiation level was 2~3 mSv/h on surface of fuel assemblies. It is not so different from what I expected. They decontaminated them only by rinsing and wiping, but it could be lower if they decontaminated them more carefully.

(Question)

200 ~ 300mREM/hr is quite high. The radiation level of normal new fuel assembly is only 1/100 of that ?

(Happy11311)

According to Tepco’s official announcement, it was 50μSv/h after decontamination. It was 2mSv/h just after taken out. The reason why the radiation level was so high is they were cutting shroud on DSP side before 311 [Link], highly radioactive chips can be attached. I don’t think they are activated.

<End>

and news from Energy News.......

http://enenews.com/

05:56 PM EST on July 19th, 2012 | Leave a comment

Massive Demonstrations Working in Japan? AFP: Size and regularity of events giving gov’t pause — Prime Minister: “Nuclear energy is becoming an issue that divides the nation”, says he will “listen attentively”

04:39 PM EST on July 19th, 2012 | 12 comments

Reuters: Head of Tepco ‘shocked’ people are concerned about No. 4 fuel pool — ‘Baffled’ by criticism of company’s role in Fukushima disaster

03:41 PM EST on July 19th, 2012 | 9 comments

NYTimes: Radioactive cloud would be ‘trapped’ over Los Angeles and San Diego in case of Fukushima-style meltdown at California nuke plant -Study

02:48 PM EST on July 19th, 2012 | 3 comments

M4.5 quake hits Fukushima — Third M4 in last 24 hours

02:02 PM EST on July 19th, 2012 | 6 comments

Tepco completes covering seafloor with layers of cement mix — More coating used at Reactors 5 & 6 than for Reactors 1, 2, 3 & 4 combined (PHOTOS & VIDEOS)

12:38 PM EST on July 19th, 2012 | 47 comments

Lead scientist surprised by Japan data: Fukushima plant still leaking radiation into ocean?

11:17 AM EST on July 19th, 2012 | 9 comments

Tepco: No ‘major’ deformation or corrosion seen so far in removed fuel assemblies (VIDEO)

07:56 AM EST on July 19th, 2012 | 11 comments

WSJ speculates: “Is process of emptying the Unit 4 pool starting?” — Will Tepco continue taking out more racks? — Law forbids disclosing when nuclear fuel is moved

and what is going on with other plants worldwide ? 

THURSDAY, JULY 19, 2012

Sweden's Ringhals Nuclear Power Plant Reactor 2 Shut Down 9 Hours After the Restart, Cause Unknown

From Reuters (7/19/2012):

Sweden's Ringhals-2 nuclear reactor fails after restart

OSLO, July 19 | Thu Jul 19, 2012 2:45am EDT

(Reuters) - Sweden's Ringhals-2 nuclear reactor was shut down on Thursday morning, less than nine hours after being restarted, due to a technical glitch, the Nordic power exchange said in a market message.

The 865-megawatt (MW) pressurized water reactor's trip was caused by an elevated high-steam generator level after it was restarted at 1930 GMT on Wednesday, it added.

The reactor was previously shut a month ago due to oil leakage from a transformer, and was expected to be back in full operation after maintenance by Thursday evening.

Ringhals-2 is one of the four reactors at the plant south of Gothenburg, 70 percent owned by Swedish state energy group Vattenfall and 30 percent held by German E.ON .

Nuclear generators supply 40 percent of Sweden's power needs.

(Reporting by Nerijus Adomaitis; editing by Keiron Henderson)

I wonder whose steam generator is used.

UK's Sizewell B Nuclear Power Station in Automatic Shutdown, Cause Unknown

From UBAlert (7/19/2012):

Sizewell B nuclear power station on the Suffolk coast has had its second automatic shutdown in four months. Owner EDF Energy said electricity production had ceased at 17:11 BST on Wednesday and it was investigating the cause of the stoppage. A spokesman said: "The reactor was safely shut down, with the plant responding as expected and at no time was anyone's safety at risk." The plant had an 11-day automatic stoppage in March. EDF said it was not predicting when the plant would begin generating again. The company said the March shutdown had been the first automatic one in three years and was for an electrical fault in the non-nuclear side of the plant. There was a controlled stoppage in May to fix a lubrication problem. EDF Energy saidSizewell B produced enough electricity for two million homes, or about 3% the UK's electricity needs.

Is this kind of "automatic shutdown" with cause unknown a common event occurring at nuclear power plants all over the world, but people and the media (like Reuters) have started to pay more attention because of the Fukushima I Nuclear Power Plant accident?

(H/T anon reader) 

WEDNESDAY, JULY 18, 2012

"Unusual Event" at Limerick Nuclear Power Plant in Pennsylvania, US, Unit 1 Reactor Manually Scrammed

The Limerick Generating Station is operated by Exelon.

From Excelon's press release on 7/18/2012, announcing that the Unit 1 has been taken offline:

Limerick Operators Take Unit 1 Offline

Operators at Limerick Generating Station took Unit 1 offline this morning following an electrical disturbance on the non-nuclear side of the plant.

POTTSTOWN – Operators at Limerick Generating Station took Unit 1 offline this morning following an electrical disturbance on the non-nuclear side of the plant.

Unit 1 will remain offline until repairs, inspections and testing can be completed. Limerick Unit 2 continues to operate at full power.

As a result of the electrical disturbance, an Unusual Event was declared at 8:39 a.m. and terminated at 9:46 a.m. in keeping with NRC procedures. An Unusual Event is the lowest of four Nuclear Regulatory Commission emergency classifications.

Exelon Generation notified all appropriate federal, state and local government officials of the event. There is no threat to the health and safety of the public associated with this event.

Limerick Generating Station is located approximately 21 miles northwest of Philadelphia. With both units at full power, the site can produce enough carbon-free electricity for 2 million homes

An excellent example of not saying anything like "where exactly" and "what exactly".

According to reports, a transformer blew up in the turbine building. Here's from The Times Herald (7/18/2012):

‘Unusual event’ reported at Limerick power plant

(Updated at 10:55 a.m.) LIMERICK — The Nuclear Regulating Commission said it is closely monitoring events at the Limerick Generating Station after a manual scram around 8:15 a.m. shut down the reactor at the nuclear power plant.

According to NRC spokesman Neil Sheehan, an electrical fault was reported in a transformer in a turbine building that spurred the scram and that the transformer is not a main transformer.

The event was listed as an “unusual event” around 8:39 a.m., the lowest of the event ratings, Sheehan said. No one was injured in the incident and no outside help was requested, Sheehan said.

Sheehan said the transformers have been known to fail from time to time and that the reactor was safely shut down.

Sheehan said there are no complications at the power plant at this time and there is no danger to the public from the incident.

EARLIER VERSION OF THIS STORY

LIMERICK — An “unusual event” was reported Wednesday morning in Unit 1 of the Limerick Nuclear Generating Station.

According to Frank Custer, communications director with Montgomery County, the county received an email from Exelon, parent company of the nuclear power plant, stating that an explosion had occurred causing the “unusual event,” in Unit 1 but the event did not pose any threat to the public.

Custer said the notice reported the “unusual event” had been terminated.
A call placed to the Limerick Generating Station’s media relations spokesperson was not picked up or returned as of 11 a.m. Wednesday.