WHO: Low radiation risk from Fukushima

28 February 2013 Radioactivity released by the Fukushima accident posed a low risk to Japan’s population, said the World Health Organisation. It expects no observable health effect in the wider population, but raised estimations of cancer risk for two towns. An international team assembled by WHO looked at a number of populations in Fukushima prefecture and estimated their exposure to radiation as a result of the accident in March 2011. These exposures were then carefully extrapolated assuming a linear relationship between exposure and health damage. The results were released today in a report entitled, Health risk assessment from the nuclear accident after the 2011 Great East Japan Earthquake and Tsunami. For the general population in wider Fukushima prefecture, across Japan and beyond “the predicted risks are low and no observable increases in cancer rates above baseline rates are anticipated,” said WHO. A program of monitoring and screening was recommended. “The primary concern,” said Maria Neira of WHO, “is related to specific cancer risks linked to specific locations and demographic factors.” Of note is the population of Namie, outside the evacuation zone to the northwest of the plant where radioactive materials were carried by the wind. Those among its of around 22,000 that remained at home for four months after the accident were considered as the most exposed group and WHO estimated certain marginal increases in cancer risk that could result. The second most exposed group were those spending four months in Iitate, with risks to its population of about 7000 raised by about half the amount of Namie. WHO was careful to address an infectious fear that the accident could badly affect fertility or the health of unborn children. It said the effects of the accident “are not expected to cause an increase in the incidence of miscarriages, stillbirths and other physical and mental conditions that can affect babies born after the accident.” Estimations, attributions WHO’s use of the linear no-threshold method of gauging health effects will have resulted in a cautious overestimate of health impact. The method is controversial, given that the effects of radiation at low doses are small enough to be overwhelmed by other environmental and lifestyle factors. The WHO noted dissenting views about the highly conservative assumption, but thought it “prudent” to adopt the method, “attempting not to underestimate the risks.” Late last year the UN adopted advice from the UN Scientific Committee on the Effects...
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Russian construction milestones

28 February 2013 Construction work continues at various new nuclear power plant projects in Russia, with several milestones – including the delivery of major pieces of equipment – having recently been achieved. Reactor internals equipment has been delivered for installation at unit 1 of the Novovoronezh Phase II plant, which comprises two AES-2006 VVER-1200 pressurized water reactors (PWRs). Meanwhile, work has started on welding the main circulation pipe in the reactor building of the unit. This pipe connects the main equipment of the primary loops: the reactor, steam generators and the reactor coolant pumps. New automated orbital welding technology – specifically designed for use at Novovoronezh Phase II – is being employed. Construction of Novovoronezh II units 1 and 2 began in June 2008 and July 2009, respectively, with start-up expected in 2014 and 2016. Rostov heat exchangers Meanwhile, the first two heat exchangers for installation at units 3 and 4 of the Rostov nuclear power plant have been delivered to the construction site. A total of six heat exchangers – three for each unit – are being supplied by Russian heavy equipment manufacturer ZiO-Podolsk. Each heat exchanger measures about 8 metres in height, has an internal diameter of over 1 metre and weighs 15 tonnes. They will form an important part of the cooling systems of the reactors. Construction of Rostov 3 began in late 2009, while work on unit 4 started in mid-2010. Units 3 and 4 are set to be completed by 2014 and 2016, respectively. Leningrad-II concreting Work to concrete the outer surface of the containment vessel of the first reactor at the second phase of the Leningrad nuclear power plant (Leningrad II) has been completed by contractor Titan-2. Concreting of the inner surface of the containment vessel continues, as does concreting of both the inner and outer surfaces of the containment of unit 2. The two 1170 MWe reactors, of the AES-2006 model PWR design, are scheduled for commissioning in 2013 and 2016 respectively. Beloyarsk fuel pool Construction of the concrete floor of the used fuel storage pool in the reactor building of Beloyarsk unit 4 has been finished. When complete the storage pool will measure 42 metres in length and 15 metres wide. It is designed to temporarily store used fuel from the BN-800 liquid sodium cooled reactor until sufficient residual heat has been removed to allow its removal for processing and reprocessing....
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Court rules Biblis closure unlawful

28 February 2013 A three-month closure imposed by the government on RWE’s Biblis A and B reactors as an immediate response to the Fukushima accident was illegal, a German court has ruled. The administrative court for the German state of Hesse has found the state ministry of the environment acted illegally on 18 March 2011 when it issued an order for the immediate closure of the Biblis units. The state ministry was acting to enforce a decree issued by Chancellor Angela Merkel in immediate response to the nuclear accident at Fukushima Daiichi, ordering that all German nuclear power reactors that began operation in or before 1980 should be immediately shut down as part of a three-month nuclear moratorium. RWE complied with the decree by shutting Biblis-A immediately. Biblis-B was already undergoing a scheduled outage. Nevertheless, the company asserted that as the plants were in compliance with the relevant safety requirements the German government had no legal grounds for shutting them. Accordingly, RWE filed an appeal against the closure with the administrative court of appeal for the state of Hesse. The court has now ruled that the closure notice was illegal because RWE had not been given sufficient opportunity to respond to the order. The administrative court ruling solely concerns the legality of the closure order. Any claims for damages against the state of Hesse would be decided in subsequent civil court proceedings. The German government subsequently made the closure of the eight reactors permanent, and revived plans to phase out nuclear power by 2022. This decision, as well as a tax on nuclear fuel levied in anticipation of continued operation of nuclear plants before the phaseout decision, have cost German nuclear operators dear: RWE estimated that the phase-out cost the company over €1 billion ($1.3 billion) in 2011 alone. Lawsuits have been filed by all the nuclear generators affected by the closure order to seek redress for their losses after the effective confiscation of their rights to generate, while other lawsuits against the nuclear fuel tax are ongoing. German tax courts have already that the nuclear fuel tax is formally unconstitutional, sending the matter forward to the German Constitutional Court....
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Magnox decommissioning milestones

27 February 2013 Several milestones have been reached in the decommissioning of the UK’s fleet of Magnox nuclear power plants, including the completion of defuelling at Chapelcross and the removal of a transformer from the Oldbury site. The final shipment of used fuel from the UK’s Chapelcross nuclear power plant has been sent for reprocessing at Sellafield, marking the end of a four-year operation to remove all fuel from the site. Chapelcross in Scotland was one of the world’s earliest nuclear power plants, with four 49 MWe Magnox units operating from 1959 and 1960 until 2004. Magnox Ltd, which manages the Chapelcross site on behalf of the Nuclear Decommissioning Authority, received approval from the Office of Nuclear Regulation in July 2008 to start defueling the Chapelcross site. The first shipment of fuel to Sellafield left Chapelcross in April 2009. Magnox announced that the final flask containing used fuel from Chapelcross left the site on 26 February. This landmark was reached four months ahead of the original target to remove all the used fuel from the site by June 2013 and six weeks ahead of a challenge later set by the NDA to complete fuel removal by March. In total 38,075 fuel elements have been transported from Chapelcross to Sellafield in 257 flask shipments over the past four years. This, Magnox said, has removed 99% of the radioactivity from the site. It noted that following verification work over the next few months, the Chapelcross site will be declared completely free of nuclear fuel for the first time in more than 50 years. NDA chief operating officer Mark Lesinski commented, “This is a huge achievement for Chapelcross and for the decommissioning and clean-up program in the UK.” Although all the fuel has only just been removed from the site, various decommissioning work has already been conducted at Chapelcross since the plant stopped operating. This includes the demolition of the plant’s cooling towers in May 2007. Once verified as being clear of fuel, Chapelcross will move to a “new post-defuelling structure,” scheduled to begin in September 2013, as work continues to prepare the site for entering into interim care and maintenance in 2017. Final site clearance is expected by 2095. Oldbury transformer Meanwhile, Magnox reported that the generator transformer has been removed from the site of the Oldbury nuclear power plant in Gloucestershire. The transformer – measuring over four metres high, four metres...
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New chief for WANO

27 February 2013 Ken Ellis will take over as managing director of the World Association of Nuclear Operators (WANO) in April. He comes from a background of operations at Bruce Power in Canada. Ellis will replace George Felgate, formally taking control on 1 April to be based at WANO’s London office. He said his top priorities are the organisation’s long-term plan and its post-Fukushima work. Ellis served Bruce Power as executive vice president of strategic support and formerly as chief nuclear officer. His career spans 31 years of nuclear operations, maintenance and engineering. Outgoing managing director George Felgate plans to retire. He took up the role in 2009 after 27 years at the Institute of Nuclear Power Operations (INPO) during which he rose to become vice president of plant operations. He oversaw WANO’s recent restructuring, set up an Executive Leadership Team and expanded and relocated the London office. WANO was established in 1989 as a forum for the exchange of safety knowledge and operating experience among all nuclear operators worldwide. The move was a reaction to the 1986 accident at Chernobyl and WANO was modelled on INPO, which was itself the US industry’s response to the 1978 accident at Three Mile Island. An office in London hosts WANO’s central secretariat, while its work programs are executed by regional WANO centres in Atlanta, Paris, Moscow and Tokyo as well as by a smaller office in Hong Kong focused on pre-startup reviews....
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