Current Issues: Waste Management of Depleted Uranium: Storage
(last updated 15 Sep 2017)
> see also:
On 2 July 2009, the Urenco Limited Board approved capital expenditure of EUR 360 million for the creation of a Tails Management Facility (TMF) at URENCO's Capenhurst site, north-west England, UK. Construction of the Facility will include a 7,000 tU per annum capacity (2 kiln) tails hex deconversion plant, a hex cylinder washing plant, a uranium oxide store and associated support facilities.
The construction programme will commence in the coming months, with completion target and online date scheduled for 2014.
(Urenco 13 July 2009)
> See also: British Nuclear Group Sellafield Limited Capenhurst site
UK plans to commence deconversion of legacy depleted uranium hexafluoride inventory by 2020
In March 2010, the Nuclear Decommissioning Authority issued its Storage Strategy for NDA Owned Uranium Hexafluoride Tails 2010:
"[...] Hex tails that are not planned to be either sold or returned to the fuel cycle would need to be deconverted. [...] Subject to NDA estate-wide funding and hazard reduction priorities, the present intent is to commence deconversion by 2020 and earlier if this is practicable. [...]"
> Download Storage Strategy for NDA Owned Uranium Hexafluoride Tails 2010 (31k PDF - NDA)
Depleted uranium hexafluoride leak from corroded legacy cylinder demonstrates urgency for tails disposition at Sellafield Ltd's Capenhurst site
"On 24th July , the licensee promptly notified NII of a seepage of a few litres of radioactive liquor from a corroded stored uranium hexafluoride legacy "Hex Tails" cylinder, held inside a storage building. The Site Emergency Control Centre was appropriately manned for several hours, whilst the leak was promptly brought under control and sealed by the 'on site' Fire & Rescue team. There was no escape of radioactivity from the building and no personnel were contaminated. The volume (about three litres) and specific radioactivity of the acidic liquor, which had leaked from the ageing "Hex Tails" cylinder in a small localised area, breached the level defined within the Ionising Radiations Regulations 1999. [...]
This event has clearly significantly enhanced the need for timely "Hex Tails" disposition and NII will continue to press for the development and timely implementation of detailed plans for elimination of the "Hex Tails" hazard from the Sellafield Limited site at Capenhurst."
(Sellafield Limited Capenhurst Works, NII site inspector's quarterly report to the local stakeholder group for 1 July 2009 to 30 September 2009)
Nuclear Installations Inspectorate presses British Nuclear Group to deal with hazard from uranium hexafluoride tails stored at Capenhurst
"[...] NII continues to actively press the licensee to develop the options to bring forward the date for the commencement of processing or disposing of the legacy 'Hex Tails' uranic and other materials currently stored on site, taking account of wider developments. The licensee continues to provide the site inspector with visibility of the ongoing work to review acceleration options. NII was encouraged that the licensee was now actively engaged in reviewing the options to address the 'Hex Tails' legacy, with a view to reducing the potential hazard from this legacy material, earlier than currently programmed in the Lifetime Plan. Some interim acceleration milestones were incorporated within the 2007/08 Lifetime Plan. NII will continue to press for progress to be made by the licensee towards the timely reduction of this medium term site hazard."
(British Nuclear Group Sellafield Limited Capenhurst Works, NII site inspector's quarterly report to the local stakeholder group for 1 January 2007 to 31 March 2007)
"[...] NII continues to actively press the licensee to develop the options to bring forward the date for the commencement of processing the legacy 'Hex Tails' uranic materials currently stored on site, taking account of wider developments. The licensee has agreed to present the outcome of the current review of acceleration options to NII and EA before the end of 2006. NII was encouraged that the licensee was now actively engaged in reviewing options to address the 'Hex Tails' legacy, with a view to reducing the potential hazard from this legacy material, earlier than currently programmed. NII will continue to press for progress to be made in the timely reduction of this medium term site hazard." (British Nuclear Group Sellafield Limited Capenhurst Works, NII Site Inspector's Quarterly Report to the Local Stakeholder Group for 1 July 2006 to 30 September 2006)
BNFL installs windows at DU storage facility to enhance transparency...
"2.3 Long Term Storage of Uranium at Capenhurst
Progress continues to be made in the construction of stores in the ex Diffusion Plant Building. These stores are being provided with windows so that the stores and their contents can be viewed by the public."
(BRITISH NUCLEAR FUELS PLC, CAPENHURST WORKS, QUARTERLY REPORT FOR 1 APRIL 2001 TO 30 JUNE 2001)
Further depleted uranium storage building at COVRA site officially opened
On 13 September, Princess Beatrix officially opened a new building for depleted uranium storage located at COVRA's site in the Netherlands. COVRA is a state-owned organisation that stores both low level radioactive waste, like depleted uranium and high level waste produced by industries and the medical sector.
The new building will allow depleted uranium to be stored responsibly and safely for at least 100 years.
(Urenco Sep. 14, 2017)
Cutter strokes found on railcar carrying depleted U3O8 from Tricastin (France) to the Netherlands
> View here
Failure in brake system of railcar transporting depleted U3O8 from Tricastin (France) to the Netherlands
> View here
Environmental Impact Statement submitted for modified plan to extend depleted uranium storage at COVRA radioactive waste facility
> View COVRA release Dec. 6, 2013 (in Dutch)
> Download EIS summary (1.7MB PDF - in Dutch)
> Download Covra's license modfication request (Ministry of Economics, March 6, 2014 - in Dutch)
Railcar with depleted U3O8 destined for the Netherlands derailed in France
> View here
Comment invited on planned extension of depleted uranium storage at COVRA radioactive waste facility
On Feb. 22, 2012, the Dutch Ministry of Economics (EL&I) announced the availability of an Environmental Impact Report for COVRA's project of a further storage building for depleted uranium in Vlissingen.
Comments have to be submitted by April 4, 2012.
> View EL&I announcement
Export statistics for depleted uranium from France to the Netherlands
These exports apparently comprise the material originating from Urenco's Almelo plant and sent back for disposal at COVRA's Vlissingen site, after deconversion from uranium hexafluoride to U3O8 at Areva's Usine W in Pierrelatte.
Source: Haut Comité pour la Transparence et l'Information sur la Sécurité Nucléaire , Nov. 2009
|Year||DU exports [t U]|
COVRA opens new uranium oxide storage halls for depleted uranium from Urenco's Almelo enrichment plant
"On the 2 July 2008, COVRA (the national storage facility for radioactive
materials in the Netherlands) opened two additional storage halls for storing
Urenco's depleted uranium at its facility in Vlissingen in the Netherlands.
Since the COVRA opened the depleted uranium building in 2004, its first
hall is now almost at full capacity. With the opening of these new halls,
availability of safe, long-term, retrievable storage of depleted uranium will
be ensured for years to come.
As part of Urenco's commitment to safety, it uses COVRA's facilities to store
depleted uranium from the enrichment process. Depleted UF6 is sent to
a facility in France, where it is converted to U3O8, a more stable form of
uranium and therefore suitable for long term storage. COVRA takes over this
material from Urenco, which is then shipped to Vlissingen in steel containers
each of which holds 10 metric tonnes of U3O8.
Each hall holds a maximum of 650 containers, which will provide safe,
reliable storage of the oxide for a further 100 to 150 years. Many years in
the future, a decision will be made by COVRA as to whether the material
can be reused or needs to be put into final storage."
(Urenco News Magazine Autumn 2008)
Dutch Ministry discloses details on Urenco Almelo's depleted uranium disposition at COVRA
On Nov. 27, 2007, the Dutch Ministry of Environment (VROM), in an answer to a parliamentary question, disclosed that approximately an annual amount of 3700 t, that is almost half of the depleted uranium generated at Urenco's Almelo enrichment plant, is sent to the Centrale Organisatie Voor Radioactief Afval (COVRA) radioactive waste facility, where it is stored.
> Download Beantwoording Kamervragen lid Poppe 2070802570 over transport van kernafval (MS Word, in Dutch)
Commissioning of depleted uranium oxide storage building at Urenco's Gronau site deferred indefinitely, while DU oxide is transferred to Capenhurst
Urenco has again deferred the commissioning of the depleted uranium oxide storage building at its Gronau site. After the last announced commissioning date had passe by, Urenco did not announce a new commissioning date. The building was completed in 2014 already.
In 2016, Urenco has swapped 10,100 t of depleted U3O8, resulting from the de-conversion (in France) of 12,700 t of depleted UF6 (tails) originating from its Gronau enrichment plant, for depleted UF6 (tails) from its Capenhurst (UK) plant for re-enrichment at its Gronau plant.
(Westfälische Nachrichten Jul. 21, 2017)
First usage of depleted uranium oxide storage building at Urenco's Gronau site deferred further to 2019, at the earliest
According to the answer of the Northrhine Westphalia state ministry of economics to a parliamentary question, Urenco plans to commission the depleted uranium oxide storage building at its Gronau enrichment plant in the first half of 2017, but uranium will not be stored before 2019.
(Westfälische Nachrichten Jan. 13, 2017)
Urenco defers commissioning of depleted uranium oxide storage building at Gronau further to 2017
According to a letter of the Northrhine Westphalia state ministry of economics, Urenco plans to defer the commissioning of the depleted uranium oxide storage building at its Gronau enrichment plant further, probably to the first half of 2017.
(Westfälische Nachrichten Aug. 9, 2016)
Urenco Gronau still has not submitted an application for commissioning of depleted uranium oxide storage building
According to the reply of the Northrhine Westphalia state government to a parliamentary question, Urenco still has not applied for an operating license for the newly built depleted uranium oxide storage building at its Gronau site.
> Download: Antwort der Landesregierung auf die Kleine Anfrage 4553 vom 8. März 2016 des Abgeordneten Hanns-Jörg Rohwedder PIRATEN - Drucksache 16/11457 - Geplante Eröffnung des neuen Uranoxid-Zwischenlagers auf dem Gelände der Urananreicherungsanlage Gronau , Landtag Nordrhein-Westfalen, 16. Wahlperiode, Drucksache 16/11738, 14.04.2016 (137k PDF - in German)
Commissioning of Urenco's Gronau depleted uranium oxide storage building expected in early 2016
Urenco's new depleted uranium oxide storage building in Gronau will be commissioned not before early 2016, according to Urenco spokesman Dr Chris Breuer.
(Westfälische Nachrichten May 6, 2015)
Application for operating license of Urenco's Gronau depleted uranium oxide storage building expected in 2015
According to the reply of the Northrhine Westphalia state government to a parliamentary question, Urenco plans to apply for an operating license for its depleted uranium oxide storage building in 2015.
> Download: Antwort der Landesregierung auf Kleine Anfrage: Atomtransporte von und nach Gronau in 2014 sowie drohende Inbetriebnahme der neuen Uranoxid-Lagerhalle, Drucksache 16/8250, 26.03.2015 (3.3MB PDF - in German)
Activists block rail siding of Urenco's Gronau enrichment plant in protest against planned storage of depleted uranium oxide
According to the motto "bulky refuse instead of nuclear waste" activists blocked the rail siding of Urenco's Gronau enrichment plant with bulky refuse in the morning of Jan. 8, 2014. The protest addressed the planned storage of depleted uranium in oxide form in a newly built on-site storage building. The activists in particular expressed their disapproval of the unlimited operating license for the enrichment plant, resulting in unlimited generation of the by-product depleted uranium.
(SofA Münster Jan. 8, 2014)
> View photos (Indymedia)
Urenco's Gronau depleted uranium oxide storage building not to be used before 2015
Although the storage building for depleted uranium oxide at Urenco's Gronau site is already completed, the company intends to file an application for the operation of the facility only in 2015 - for unspecified "internal causes".
The amount of depleted uranium hexafluoride currently stored on site is 12,856 t, almost twice the amount stored end 2012.
(Westfälische Nachrichten Aug. 20, 2014)
No final disposal site required for depleted uranium oxide that is to be stored at Urenco's Gronau plant
In the answer to a parliamentary question, the German federal government stated that the depleted uranium oxide that is to be stored at Urenco's Gronau plant is a resource (rather than a waste), and that therefore there is no need for a final disposal site for the material.
(Bundestags-Drucksache 17/13598 , 21.05.2013)
Urenco's Gronau depleted uranium storage facility project licensed with no time limit
According to the answer of the German federal government to a parliamentary question, Urenco's depleted uranium storage facility in Gronau is licensed with no time limit.
(Bundestags-Drucksache 17/12943 , 27. März 2013)
Urenco's depleted uranium oxide storage building in Gronau to be completed by 2014; no air crash protection
The building projected for the storage of depleted uranium in oxide form at Urenco's Gronau enrichment plant is to be completed by 2014. Its capacity will be 50,000 t U, or approx. 60,000 t U3O8. According to the current plans, dating back to 2005, the building will not be designed to withstand an airplane crash.
(Westfälische Nachrichten May 25, 2011)
Urenco plans storage of depleted uranium as oxide
Together with the application to increase the enrichment capacity of its Gronau, Germany, enrichment plant to 4000 tonnes SWU/year (details here), Urenco has filed an application for the construction of two storage buildings for its depleted uranium waste. The depleted uranium is currently being stored as uranium hexafluoride in cylinder yards next to the plant with a licensed capacity of 38,000 tonnes of UF6. For storage, the depleted uranium is to be converted to the more stable form of U3O8 at the Pierrelatte facility in France. The buildings are to be designed for a capacity of 50,000 tonnes of uranium oxide. (Gronauer Nachrichten, April 30, 1999; Westfälische Nachrichten July 31, 1999)
> See also: 50,000 tonnes of depleted uranium oxide in use at Tricastin to shield radiation from 7,360 tonnes of stored reprocessed uranium oxide
> Aerial View (Google Maps)
Nuclear Safety Authority asks Areva to prepare additional storage capacity for depleted uranium, as Bessines storage reaches capacity
The Nuclear Safety Authority (ASN) expects the depleted uranium storage at Bessines to be full by 2022. ASN therefore asks Areva to take the necessary measures to provide additional storage capacity.
(Gestion des matières radioactives, PNGMDR, Cas de l'uranium appauvri, presentation delivered by ASN at: Commission de suivi de sites Haute-Vienne, Anciennes mines d'uranium, 30 novembre 2016)
Depleted uranium storage at Bessines reaches 75% of licensed capacity
The depleted uranium storage at Bessines currently has reached 75% of the licensed capacity [of 199,900 t].
(Bilan ICPE depuis la CSS de juin 2015, Commission de suivi des anciens sites miniers uranifères de Haute-Vienne, 30 novembre 2016)
Anti-nuclear sabotage claimed to have caused derailment of locomotive on siding to Areva's depleted uranium storage facility at Bessines
Anti-nuclear activist would have caused the derailment of a train Friday (July 12) in Fromental. Bolts were removed [from a fishplate at the track] and the locomotive running a small railway line used to access Areva's site has left its path. No one was injured. Sabotage was claimed toward our newspaper by email.
"The small railway line used exclusively to transport nuclear waste to Areva's site Bessines on Gartempe was put out of operation. This action intends to expose a storage site for nuclear waste that dare not speak its name. It is dangerous and must be dismantled."
This derailment occured on the same day Areva's Urêka museum, devoted to uranium mines, was inaugurated.
(Le Populaire du Centre July 12, 2013)
SNCF has filed a complaint for "endangering the lives of others" and Areva for its part, filed a complaint against X for sabotage.
According to Le Populaire du Centre, two employees of SNCF present on scene have also complained.
The derailment occurred the same day as the train crash that killed six people at Brétigny-sur-Orges (Essonne), but the SNCF cautions that any comparison with the partial derailment likely due to a malicious act would be "adventurous", even if it's a fishplate in both cases.
(Le Populaire du Centre July 17, 2013)
No depleted uranium added to Bessines storage for one year
As of May 17, 2011, no depleted uranium has arrived at Bessines since May 17, 2010. The next shipment is expected for June 2011.
(DREAL July 6, 2011)
Areva ignores bookkeeping requirements on isotopic composition of depleted uranium stored at Bessines site
During an inspection held on Oct. 25, 2007, the inspecteur des installations classées found, among others, that Areva had failed to keep track of the isotopic composition of each container stored in the facility - a major violation of the applicable regulations. At the occasion of further inspections held on Oct. 6, 2008, and on June 17, 2009, the inspector found that Areva still had not adhered to the bookkeeping requirements. The inspector was particularly concerned about possible concentrations of the artificial isotope uranium-236 which might render the whole disposal scheme illegal.
Further criticism by the inspector concerned Areva's failure to conduct reliability tests ordered for the storage containers used, among others.
(DRIRE Limousin: Rapports d'inspection et de contrôle de la Haute-Vienne: Inspection Uranium appauvri (10/2008), Inspection Uranium appauvri (06/2009))
Depleted uranium storage at Bessines nearing capacity
The storage buildings at Bessines currently hold 165,000 t U of depleted uranium oxide, while the licensed capacity is [almost] 200,000 t U. The storage could therefore become full within short time, as it continues to receive depleted uranium on a regular basis.
(Le Populaire May 14, 2009)
7,700 t U of depleted uranium oxide taken out of Bessines storage for re-conversion
Between April 2008 and January 2009, 7,700 t U of depleted uranium oxide (U3O8) were transported from Bessines to Malvési for conversion back to uranium tetrafluoride (UF4).
> View details
Cracked container carried depleted uranium across France
On October 14, 2004, traces from an impact and a hole were detected in a container carrying depleted uranium in the form of U3O8 from Cogéma's conversion facility Usine W in Pierrelatte to the DU storage site in Bessines (Haute Vienne). The 28 mm-long fissure was detected on top of the container on arrival of the rail shipment in Bessines. It is assumed that the fissure occured during handling of the container at Pierrelatte. No traces of any release of radioactive material were detected.
> View ASN release Nov. 8, 2004 (in French)
The depleted uranium storage project at the former Bessines uranium mill site
The long history of disposal of any kinds of wastes on former
uranium mine and mill sites is being enriched by a new project:
France's nuclear fuel company COGEMA
is going to store 199,900 tonnes of depleted uranium (DU) at the
site of the former uranium mill of Bessines-sur-Gartempe (Haute
Vienne) near Limoges. The project was licensed on 20 December
This license was revoked by the Administrative Tribunal of Limoges on July 9, 1998. The license was revoked mainly for the reason that the DU has to be regarded as a waste under current conditions, though an extraction of the residual uranium-235 might be viable in the future.
On Nov. 5, 1998, a Bordeaux appeals court ruled that the material is no waste, but a "directly usable raw material that is effectively used for multiple uses". Following this court decision, COGEMA sent the first DU shipment to Bessines on Nov. 12, 1998.
On May 23, 2001, the Conseil d'Etat finally turned down the appeal of the environmental organization ADEPAL against the Bordeaux appeals court ruling. The Conseil d'Etat followed the appeals court's ruling that the material is not a waste. ADEPAL was sentenced to pay 20,000 Francs (US$ 2,600) in damages to COGEMA.
At the time of this ruling, five of eleven storage buildings have been completed and 32,600 tonnes of depleted uranium have already been stored. (Info Nucléaire May 31, 2001 )
Originally, COGEMA had applied for the storage of 265,000
tonnes, but during the hearings held on the project, it became
obvious that COGEMA had "forgotten" to consider some
radionuclides in its calculation of the total activity
inventory: The specific activity of the depleted uranium is
21,100 Bq/g instead of 15,902 Bq/g. The project would therefore
have exceeded the 100,000 Curie limit, requiring a different
type of license (Installation Nucléaire de Base)
involving wider public participation.
During a public enquiry, conducted between 18 Nov 1994 and 2 Jan
1995, 10,182 citizens and organizations had voted against the DU
disposal project at the Bessines site.
A review panel (commission d'enquête) that was installed
to conduct a public enquiry on the project and to produce a
recommendation on it, followed the main views of the opponents
and issued a recommendation against the proposed
project on 23 March 1995. The reasons for this vote were the
neglected existence of artificial uranium-236 in the enrichment
wastes and the thus too high total inventory of the deposit that
would have exceeded the 100,000 Curie limit, among others.
COGEMA was not able to provide a reasonable explanation for the
presence of the uranium-236.
The depleted uranium is a residue of the Eurodif Tricastin
gazeous diffusion enrichment plant in the Rhône valley.
Its residual contents of uranium-235 is 0.2 to 0.3 % and it has
the chemical form of uranium
hexafluoride (UF6). But, COGEMA doesn't declare
it a waste, but wants to store it for possible future use.
COGEMA hopes that the stored DU can be useful, if future
enrichment techniques would allow for economic extraction of the
residual uranium-235, or if uranium prices would rise
For storage, the UF6 is to be converted to the
chemically more stable form of U3O8 at
COGEMA's Pierrelatte facility. Then it is to be transported by
rail to the Bessines site and to be stored as a powder in iron
containers. The containers (8.5 or 11 tonnes each) are to be
stored in 11 special storage buildings of 3000 m2
each, according to the original plan. Each building can store
2500 containers. The maximum dose that an individual would be
exposed to at the fence of the facility, is calculated at 0.7
mSv (70 mrem) per year, far below the (extremely high) French
limit of 5 mSv (500 mrem) for the public.
The Bessines uranium mill has ceased operation in july 1993,
since the associated uranium deposits are worked out or cannot
be mined any more under the current uranium market conditions.
So the area now faces high unemployment of former miners, and
any kind of new business is welcome. Knowing this, COGEMA now
offers to build that DU disposal facility. The total investment
is planned at 60 million French Francs (approx. US$ 10 million)
over a period of 15 years.
The storage of DU at the Bessines site is only the first of a
series of proposals made by COGEMA: others are for the
treatment and storage of thorium-wastes from the Cadarache
facility, treatment of mercury-containing wastes, and storage of
natural uranium (yellow cake).
Fédération Limousine pour l'Étude et la
Protection de la Nature - FLEPNA
Maison de la Nature, 11, rue Jauvion, 87000 Limoges, France
Tel. +33-5-55-329558, Fax: +33-5-55-327746
former Installation nucléaire de base N°134 (Magasin d'uranium de Miramas)
Information about Miramas facility (Nuclear Safety Authority - ASN, in French)
On Oct. 2, 2007, the Nuclear Safety Authority (ASN) announced that the license for the Miramas uranium storage site has been retracted after the facility has been dismantled.
> see also Clive DU disposal
Utah permits DU storage rather than disposal at Clive disposal site
On Feb. 13, 2012, the Utah Water Quality Board issued an amended Ground Water Quality Discharge Permit to Energy Solutions LLC.
The permit allows for DU storage in a designated DU Storage Building with no time limit. DU storage is exclusively limited to Savannah River Site DU material.
> Download Ground Water Quality Discharge Permit No. UGW450005, Feb. 2012 (639k PDF - Utah DEQ)
Savannah River Site completes depleted uranium metal shipments to Utah disposal site
The Savannah River Site has completed the final shipments of depleted uranium metals from an old manufacturing area at the complex, clearing the way for demolition of six buildings.
The M area buildings were the facilities where "target" materials for the site's five reactors were manufactured (The reactors produced plutonium for nuclear weapons).
Between March and June 2003, more than 2,600 metric tons of depleted uranium metal were shipped from the Savannah River Site to the Envirocare of Utah disposal site.
Officials also plan to ship 3,270 drums of depleted uranium oxide to EnviroCare in summer 2003 as part of a pilot program. The remaining 33,000 drums would be shipped during the next few years.
(Augusta Chronicle June 10, 2003)
SRS uranium storage raises concern
A federal review board has questioned whether uranium is being stored safely at Savannah River Site.
The Defense Nuclear Facilities Safety Board found that depleted uranium is being stored in corroded drums and in deteriorating buildings at the federal nuclear-weapons site.
In some cases, wooden pallets supporting stacked drums of uranium had rotted, and "significant numbers" of the drums had tilted, the board wrote.
The board also raised concerns that uranium was stored in wooden crates and cardboard boxes, increasing the risk of a fire that could affect public health beyond the boundaries of the 310-square-mile (803 km2) site.
The U.S. Department of Energy stores about 24,200 tons (21,954 tonnes) of depleted uranium at SRS.
According to the board, little progress has been made in addressing the potential safety issues which were first identified in October 1998.
(Augusta Chronicle March 21, 2002)
Mitsui Chemical Iwakuni-Ohtake plant on fire - depleted uranium stored on site
At 2:20 on April 22, 2012, the Iwakuni-Ohtake Petrochemical Complex of Mitsui Chemicals, Inc. catched fire after it was hit by lightning. One employee died and several residents in the area were injured.
The complex is still on fire, and 3379 casks of radioactive waste (200 litres per cask) and uranium for nuclear fuel are preserved on the site.
The prefectural government confirmed that depleted uranium is stocked at the site, but said it's not affected by the accident (the company is known to hold 71.1 t of depleted uranium - not necessarily all at this site).
The plant produces Hydroquinone at a capacity of 11,500 t per year, and a capacity increase by 1000 t per year was planned.
(Iori Mochizuki - Fukushima Diary , Yomiuri, Reuters, Mitsui Chemicals, Apr. 22, 2012)