Category Archives: nuclear safety

Michael Mariotte: Counterweight to Nuclear Energy (1952 – 2016)

Let us be clear: without Michael Mariotte’s decision in the mid 1980’s to devote his talents to stopping the nuclear industry, many things would be very different today. Michael could not do what he did without Nuclear Information and Resource Service (NIRS), and the many thousands of people who work with NIRS could not have produced the results they did without Michael at the helm. This is one telling of this story.

Dispassionate passion: The smartest one in almost any room… but never resting on his own analysis; always digging, asking the next question, checking the facts. Michael Mariotte was a journalist and an organizer and at bottom it was these talents that made his leadership of the civilian end of the US anti-nuclear community so deft. Michael’s dispassion was sometimes misunderstood as indifference, but he was standing back, watching as the pieces of a puzzle would come together. Michael’s ability to zero-in with the precision of a hawk on the pressure point that could lead to change, and then write the words that would mobilize thousands onto a path of action created much of the passion in our community that has resulted in so many victories over the last thirty years. (See Victories below.)

Michael’s dedication to evidence and documentation provided credible, reliable information and analysis from routine reporting to hardcore litigation. He fully supported and sometimes led nonviolent direct action.

Writing: Michael’s 31+ year tenure at NIRS is characterized by dedicated writing. He joined NIRS in February 1985 to write and edit Groundswell, NIRS publication for the Grassroots Anti-Nuclear Movement which provided in-depth reporting and analysis. In it Mariotte wrote articles so classic (including Nuclear Is Not the Solution the Greenhouse Problem) that many, if reprinted today, would hardly need update. NIRS had already established itself as the Go-To source for information on reactor operations and capacity factors, which were calculated weekly by staff and published twice a month in The Nuclear Monitor. Prior to the internet, this publication was the only readily available source of good facts on nuclear energy performance, and lack thereof, for the financial and policy worlds. He did not pursue a desire to go into the field of socially responsible investing rather stayed with NIRS to inform that realm of the financial and other dangers of nuclear power and its fuel chain. Michael kept The Nuclear Monitor alive and expanded it when publication of Groundswell ended (circa 1989). By 2000 with a staff of seven, he was far too busy with other aspects of NIRS work to write as he had before. Indeed hand-off of the publication of The Nuclear Monitor was a key element in NIRS’s affiliation with the World Information Service on Energy (WISE) that year. WISE continues regular production of the Nuclear Monitor in conjunction with NIRS.

Michael’s commitment to reporting shown through again on his daily log of events as the Tokyo Electric Power Company (TEPCO) Fukushima Daiichi meltdowns unfolded in 2011. The NIRS website often “broke” news that was only reported by others days and weeks later. Michael gave equal voice to the post-Chernobyl era when he visited Pripyat in 1996, organizing delegations of experts and activists. He visited Germany in 1997 and 1998 during the massive demonstrations and blockades against nuclear waste transport to a centralized nuclear waste site. In these travels Michael helped establish the NIRS / WISE network, a global chain of grassroots “relays” spanning the globe. The European portion of this network, with Michael and Tanya Murza (to later become his wife), hosted a major conference on Chernobyl in Kiev, 2006, the 20th anniversary of that nuclear horror.

GreenWorld, Michael’s blog is the “bookend” bringing Michael back to his first love: clear, insightful and often acerbic reporting on the state of the nuclear escapade. He started it in 2013 when he handed the NIRS Executive Director position to Timothy Judson, who had been a young activist at the Action Camps years before. As he moved into his role of NIRS President, GreenWorld became his primary platform for the last two-plus years. Michael’s last post May 2, 2016 was only two weeks before his death.

Legislative Action: Choose your battles. Do what you can to maximize your odds. Walk away when you can’t win, but be sure to reveal the tilt in the table as you go. Michael and NIRS lost some legislative battles in the 30 years that Michael led NIRS, but we won a lot more and a very key reason for that was that Michael knew how to “count votes.” Better than almost anyone. He retained a universe of small bits of information that he gathered in numerous dimensions that added up to a very keen sense of who we “had” on our side in Congress; who was hopeless; and how to swing the others. NIRS lost when Congress reversed what had been an enormous NIRS legal victory on reactor licensing, passing legislation allowing streamlined “one-step” licensing of new nuclear reactors… but the silver lining in the same energy bill, was NIRS’ equally historic reversal of the Nuclear Regulatory Commission (NRC)’s policy called “Below Regulatory Concern” that would have deregulated about 1/4 of nuclear power’s so-called “low-level” radioactive waste and permitted it to be disposed into regular trash and commercial recycling streams. Michael was not a fundamentalist, he was a realist. At the same time he believed firmly that people have the real power.

In 1995, in the face of industry and government efforts to make the technically, morally, legally flawed Yucca Mountain site in Nevada on Western Shoshone land the nuclear power high-level waste dump, Michael designed the Stop Mobile Chernobyl Campaign. This national effort successfully stopped industry efforts to revise the Nuclear Waste Policy Act to allow shipment of the intensely radioactive nuclear fuel to the Yucca Mountain Site prior to approval of that site as a permanent repository. Enlisting the populations along the nuclear transport routes expanded our community greatly and the Stop Mobile Chernobyl campaign became a signature for building NIRS’s base at the very time that email and on-line organizing was being invented.

In the Bush-Cheney years, and on into the Obama administration, Michael and NIRS had a coordinating role in a large coalition of national groups opposing taxpayer funded nuclear “loan guarantees” that would underwrite new reactor development, and other subsidies to the nuclear industry. The coalition stopped expansion of this program time after time and created much more scrutiny for the loan-guarantee program overall. Michael did the grassroots outreach and action alerts that resulted in hundreds of thousands of electronic “hits” to congress over that period.

Electronic Organizing: NIRS had a computerized database of its supporters in the early 1990s thanks to Michael. As soon as “dial-up” existed, he created the very first electronic bulletin board that anti-nuclear people could post to… back before WINDOWS or “Websites.” When the NIRS website was set up, Michael became its librarian, personally posting thousands of relevant documents in a public space where people can download any of them ( Michael created email distribution lists as soon as there was email, long before the advent of on-line email list services like “Democracy in Action.” When these major on-line list utilities became available, Michael helped NIRS supporters to swell into the tens of thousands.

Legal Action: Michael supported a great many grassroots actions to challenge nuclear licenses. This included research, recruiting experts, referrals to attorneys, bird dogging any Congressional and NRC actions on the cases and providing coverage in NIRS publications. He himself stepped into the ring (pro se) in 2008 as part of the Chesapeake Safe Energy Coalition, filing a challenge to the proposed 3rd nuclear reactor at Calvert Cliffs on the Chesapeake Bay near Washington, D.C. The Coalition won, stopping the new reactor because of “foreign ownership,” thanks largely to Michael’s unwavering prosecution of the US utility Constellation and its French Partner, Electricité de France. NRC’s denial of a license for the construction of Calvert Cliffs Unit 3 was the first time the public had defeated a reactor operating license application, and is one of the crowning accomplishments of Michael’s long work to stop nuclear energy. This had the effect of also preventing the 9-Mile Point 3 nuclear reactor proposed in New York State on Lake Ontario by the same foreign ownership partnership.

NIRS, with local New Jersey organizations, challenged the license extension of the Oyster Creek nuclear reactor, the first time a full hearing was held and a contention accepted by the Atomic Safety Licensing Board. The historic contention was against continued operation of this Fukushima-Mark 1-style reactor with a severely corroded dry-well containment, pitted to half the thickness of the wall in many places at the bottom.

Michael pursued and publicized tips NIRS received that the fire barriers in many nuclear reactors were actually made out of combustible, flammable material (Thermolag). This resulted in major legal actions within the industry against the fraudulent company.

He supported NIRS staff, along with Union of Concerned Scientists, expert watch-dogging of the Davis-Besse reactor pressure vessel corrosion (“hole in the head”) and demand for investigation into NRC’s mishandling of the near disaster. This might have saved the world from a nuclear tragedy near Toledo in 2002, time-wise mid-way between Chernobyl and Fukushima.

NIRS was part of the successful court challenge to inadequate radiological standards for proposed high level radioactive waste repository at Yucca Mountain.

In 1999 Michael backed a creative scheme to ask the NRC to require renewable energy back-up power on all reactor sites in time for the 1999 “Y2K” computer roll-over.

Grassroots: All of the work NIRS has done has been possible because of the engagement with local people in all 50 states, Washington, D.C. and other countries. Whether shining a spotlight on a bad federal regulation, pushing on Congress to do the right thing, or raising funds to pay expert witnesses, it is only possible with the hundreds and often thousands of NIRS supporters and allies taking action. Michael believed in this: we, together, have the power. He several times worked to mobilize people in a bigger way. He was part of the MUSE (Musicians United for Safe Energy) at Madison Square Garden and outside the Capitol in DC (1979) and its revival in 2011 in Mountain View in the wake of Fukushima meltdowns. Michael instigated six Action Camps to train grassroots activists from 1998-2001 and supported two “climate convergences” in 2007 and 2008, all to teach nuclear issues and non-violent direct action. Michael also knew that NIRS and our community must lead on climate. He mobilized our community to be a key hub of the People’s Climate March in 2014 and the Paris Climate Summit activism in 2015. Michael knew how to move a movement. Michael also had absolutely no interest in the kind of drama that haunts some long-term leadership roles. This was a tremendous asset: NIRS staff were cut lose to WORK, to research, educate, organize, coordinate with the safe energy advocates across the country and around the world.

VICTORIES: None of these belong to Michael any more than the grassroots leaders, funders, and hundreds to tens of thousands of people who take action… but Michael put his War Horse stamina and courage of conviction into all of these and more…:

Nuclear Reactors Shutdown:

Since Michael took the helm at NIRS these operating reactors shutdown:
Big Rock Point
Crystal River 3
Connecticut Yankee
Yankee Rowe
Maine Yankee
Millstone 1
San Onofre 1, 2, 3
Zion 1, 2
Rancho Seco
Fort St. Vrain
Vermont Yankee

Reactor License Challenge:

Every single new US Construction / Operating License (COL) was challenged by NIRS or the grassroots network which NIRS supports.

Fuel Chain Front-End:

Michael’s support for, strategy and advocacy on behalf of an impoverished African American community in Homer, Louisiana were instrumental in stopping a uranium enrichment facility proposed a by major US European consortium. The NRC decision denying the license was an early environmental justice victory which is cited in law school text books. After Tennesseans kicked it out of their state, NIRS legally challenged it again in New Mexico.

Energy Economics:

Michael helped to ensure that the budding socially-responsible investment community was fully informed about the tremendous financial debacle of the first-build of reactors, which included 99 cancelations, many after significant investments by teacher’s retirement funds and others. He worked with international allies to prevent investments in reactors and nuclear fuel chain facilities.

So-Called “Low-Level” Waste:

The 1985 Low-Level Radioactive Waste Policy Amendments Act triggered scores of industry and government attempts to site new dumps. NIRS, with Michael’s strong support, assisted challenges in 20 states against new unlined, soil trench burial of so-called “low-level” waste (some hotter than nuclear weapons high level waste), weakening regulations and shifting liability for commercial nuclear power waste to states. NIRS continues to fight to keep radioactive waste from being deregulated or cleared from radioactive controls. Michael was instrumental in the big victory overturning the NRC “Below Regulatory Control” or BRC Policies in 1992 but repeated that fight eleven more times against NRC and other federal and state agencies and international entities.

High-Level Waste / Mobile Chernobyl:

Consolidated storage sites stopped during Michael’s tenure:
West Virginia
Mescalero Apache Reservation (NM)
Skull Valley Goshute Reservation (UT)
Yucca Mountain, Western Shoshone land (NV)
The Nuclear Waste Negotiator was defunded and 25 tribes sent “bribe” money back to DOE
The Stop Mobile Chernobyl Campaign educated the nation on nuclear waste transport and supported President Clinton’s veto of revisions to the Nuclear Waste Policy Act.
The DOE’s license application for a repository at Yucca Mountain was withdrawn and the Nuclear Regulatory Commission stopped reviewing it (until reversed by court order).

MOX / Plutonium:

Every step of the MOX (mixed oxide) plutonium fuel program was challenged and every license step had an intervention

Climate Change:

In 2006, Michael helped mobilize an international alliance of anti-nuclear groups for United Nations climate talks in Copenhagen, which prevented nuclear power from being adopted as a solution to global warming. In 2014, he orchestrated a mobilization of thousands of anti-nuclear activists for the People’s Climate March under the banner of a Nuclear-Free, Carbon-Free contingent.

After a brave struggle against pancreatic cancer for three years, Michael died peacefully at home and his family on May 16, 2016 at 63 years of age. He is survived by his wife Tanya, their young daughters Zoryana and Kateryna, his friend and ex-wife Lynn, and their children Nicole and Richard, as well as his sister Julie, brother Jeff, and sister-in-law Marsheila. And of course he leaves a seasoned, experienced and growing anti-nuclear movement with many more victories to win. He asked friends and colleagues to do something fun in his memory. That was his way, to honor life by living and enjoying it to the fullest.

* * *

Washington Post Obituary

Washington City Paper Obituary

New York Times Obituary


How low can they go? Hansen, Shellenberger now shilling for Exelon

Exelon's Clinton reactor nearly bankrupted the small utility and rural co-ops that originally built it. Despite being bought for a few cents on the dollar by Exelon, it still isn't economic and Exelon is "threatening" to close it. Photo by

Exelon’s Clinton reactor nearly bankrupted the small utility and rural co-ops that originally built it. Despite being bought for a few cents on the dollar by Exelon, it still isn’t economic and Exelon is “threatening” to close it. Photo by

While some potential legal challenges remain, the approval of the Exelon-Pepco merger by the Washington, D.C. Public Service Commission means that Exelon is now not only the largest nuclear powered utility in the U.S., it is the largest electric utility period. And with that steady stream of regulated, and non-nuclear, Pepco money filling its coffers, you’d think that Exelon’s continuing “threats” to close up to three of its Illinois reactor sites unless it obtains more bailouts from beleaguered Illinois taxpayers and ratepayers would fall on deaf ears. Or maybe Exelon is now trying to achieve “too big to fail” status? Continue reading

Governor Cuomo’s schizophrenic nuclear policies

NY Governor Cuomo thinks Indian Point is too dangerous to operate. He's right. But why are upstate reactors any different?

NY Governor Cuomo thinks Indian Point is too dangerous to operate. He’s right. But why are upstate reactors any different?

In mid-1986, New York Governor Mario Cuomo was asked about the future of nuclear power. The future of nuclear power, he replied, “is Chernobyl.” He understood that nuclear power is dangerous, and he understood that it could never become safe enough to use. He made good on that statement too: he decided to prevent the Shoreham reactor on Long Island, for which construction was basically completed and it had even been tested at very low power, from ever operating. Continue reading

80 years? Not very likely.

The bathtub curve for aging reactors, developed by David Lochbaum of Union of Concerned Scientists. Most U.S. reactors are already in the right side of the tub, with both costs and safety risks increasing.

The bathtub curve for aging reactors, developed by David Lochbaum of Union of Concerned Scientists. Most U.S. reactors are already in the right side of the tub, with both costs and safety risks increasing.

Last week, CNBC ran a story sure to elevate the blood pressure of clean energy activists everywhere: No more nukes? How about another 80 years of them. The article discussed the hopes of some in the nuclear industry that reactors will be able to be re- re-licensed and operate for 80 years instead of the original 40-year license period as well as beyond the 60 year license most U.S. reactors (75 of the 99 operating) already have received.

CNBC named names too: it said that Exelon, Duke Power and Dominion Resources are all considering applying for an additional 20-year extension to be able to operate for 80 years. Exelon is thinking about it for its Fukushima-clone Peach Bottom reactors in Pennsylvania, Dominion for its Surry reactors in Virginia and Duke Power for its Three Mile Island-clone three-unit Oconee plant in South Carolina. Continue reading

The EPR “anamoly;” what’s at stake for Areva

Installation of the reactor dome at Areva's EPR reactor at Flamanville, France. Now, indications of a serious problem with the reactor pressure vessel could scuttle the already delayed and over-budget project.

Installation of the reactor dome at Areva’s EPR reactor at Flamanville, France. Now, indications of a serious problem with the reactor pressure vessel could scuttle the already delayed and over-budget project.

 In early April, the troubled French nuclear reactor manufacturer Areva announced that there is an “anamoly” in the reactor pressure vessel installed at Electricite de France’s (EdF) Flamanville reactor currently under construction.

While the U.S. thankfully appears to have avoided any construction of the Areva EPR reactors–the U.S. EPR flagship reactor at Calvert Cliffs-3 was defeated in NRC licensing hearings and EdF has announced it is giving up on the U.S. market–EPRs remain under construction elsewhere, most notably in France, Finland and China.  Areva–the world’s largest reactor manufacturer–is already near bankruptcy; if this “anamoly” is endemic to Areva EPRs it could put the final nail in Areva’s coffin.

We appreciate the work of Yves Marignac of WISE-Paris, who prepared the following paper on what the problem is, how extensive it may be and its implications for Flamanville and the rest of the world.

Fabrication Flaws in the Pressure Vessel of the EPR Flamanville-3

Fabrication defects detected at the end of 2014 in upper and lower heads of the Flamanville-3 reactor pressure vessel are, by size and characteristics, very serious mechanical defaults. These phenomena strongly put into question the safety case of the EPR (European Pressurized Water Reactor) currently under construction in Normandy.

The reason why a well-known material heterogeneity problem was not solved during the forging of the pieces at Areva’s Le Creusot plant has yet to be investigated. The reason why the defects were detected or publicly released so late, at a moment when the pressure vessel was already in place in the reactor building, also needs to be scrutinized.

Areva will face a very difficult challenge in justifying the safety case for the flawed pressure vessel. The only alternative to demonstrating safety in spite of the defects would be to repair or replace the faulty components, which appears hardly feasible and particularly expensive in the case of the bottom piece. Therefore the future of the entire Flamanville-­3 project is at stake.

The problem has also international implications, since at least some of the upper and/or lower heads of the Taishan-­1 and -­2 EPRs, under construction in China, are apparently also affected. It is also not clear whether components destined for the Hinkley Point-­C have been fabricated yet and could be concerned.

On the 7th of April 2015, the French Nuclear Safety Authority (ASN) announced that fabrication defects had been found in the reactor pressure vessel (RPV) of the EPR reactor under construction at Flamanville. This information was soon confirmed by the manufacturer of the components, Areva, and the operator, EDF. Additional information was published by ASN on 8 April 2015. The following is a synthesis of this information completed by direct e-mail and phone communication between ASN and WISE-­Paris on 9 and 10 April 2015, and some additional research.

Safety Significance of the Reactor Pressure Vessel
The pressure vessel, which hosts the fission reaction of the nuclear fuel, is one of the most crucial pieces of equipment for the safety of a nuclear reactor. This is even more true in the case of the EPR: with a design capacity of 1,650 MWe, its pressure vessel would hold more nuclear fuel, and therefore a higher potential of danger, than any other reactor in the world. In particular, to exclude any breach of the pressure vessel is key in the safety assessment.

Considering the extreme kind of mechanical, hydraulic, thermal and radioactive loads it is exposed to, this imposes very stringent requirements for the mechanical toughness of the pressure vessel. The design pressure is 176 bar and the design temperature is 351°C. The reactor pressure vessel of the EPR is a cylinder of roughly 12.7 meters high and 5.7 meters diameter (7 meters with the nozzles), made of five main parts: three toruses, of which the upper one holds the nozzles connecting the vessel to the primary loops, and the cap-­‐shaped bottom which are welded together, plus a separate cap-­‐shaped head. Each of these manufactured components as well as the quality of the weldings has to meet specific requirements.

The defects announced on 7 April 2015 concern the pressure vessel head and bottom of the
Flamanville-­3 EPR. Unlike the largest parts of the pressure vessel that were forged by Japan Steel Works (JSW–operating the only forge in the world that can process the very large EPR vessel ingots–these smaller parts could be forged by Areva in its plant at Le Creusot.

Nature of the Defect
The vessel closure head is made up of a forged ring, the vessel flange, and a forged partly spherical upper head, penetrated by welded tubes. The lower head is a similar partly spherical forged piece, welded through a forged transition ring to the central core shells. The whole body of the pressure vessel weighs 410 tons, while the vessel head weighs an additional 116 tons.

China's Taishan 1 and 2 reactors, now under construction, may be affected by Areva's pressure vessel problems.

China’s Taishan 1 and 2 reactors, now under construction, may be affected by Areva’s pressure vessel problems.

The pieces are all made of 16MND5 steel. The defect consists in carbon segregation in a certain area of the partly spherical upper and lower heads. It occurs due to insufficient elimination during the forging process of the higher part of the ingot, where carbon tends to concentrate, in the fabricated piece. Why such a well-­known phenomenon was not avoided will be, according to ASN, an important part of its examination of the case.

The problem was found recently through destructive tests on a similar vessel head that had been forged in the same conditions. The results are as follows:

• Carbon concentration was found to reach 0.30% in the central area of the forged piece. The fabrication process should ensure, according to the technical specifications applying to 16MND5 steel, that higher concentrations found in the forged piece remain under 0.22%, which is the upper boundary for qualifying materials on the basis of existing studies and return of experience. In other words, as ASN put it, the carbon concentration in the segregated zone brings the material significantly far from the domain of knowledge where the required mechanical properties are well proven.
• This carbon concentration affects the mechanical properties of the material, and most particularly its resilience (its capacity to absorb the energy of a shock, expressed in Joules),which is one of the key properties to be assessed to qualify the pressure vessel. Samples from the segregated zone showed a resilience between 36 J and 64 J, with a mean value of 52 J. This is below the regulatory threshold for the vessel head and bottom, which is of 60 J on average. Taking into account the expected margins, the resilience aimed for and obtained in non-­segregated areas is above 100 J.
• The segregated zone is a concentric area with a diameter of around 1.20 meters, on the external face. The depth of the zone remains to be assessed.

Those results are highly likely to be transposable to the head and bottom of the Flamanville-3 pressure vessel, given the very same conditions of their fabrication. Moreover, non-destructive chemical tests on the surface of these parts have confirmed the presence of a similar defect.

Timing of the Process
The ASN was first informed by Areva of the results of the tests in December 2014. These destructive tests were part of the qualification procedure for the components of a pressurized nuclear piece of equipment which the manufacturer has to complete prior to its operation (independently of the whole approval of the reactor start-up, which has to be obtained by the operator).

The head and bottom were apparently forged as early as 2006 (even before EDF obtained the license to create the new reactor at Flamanville, which was granted by a decree in April 2007).

Major defects in the vessel closure head were found by Areva in the Autumn of 2010 and in June 2011. One concerned the welding of adaptor tubes, the other concerned the welding of more than 50 penetrating tubes (out of 107 in total). In October 2011 ASN allowed Areva to carry out deep repair work instead of fabricating a new head. Also some of the tubes probably cross the segregated zone, the reparation process, which is not complete yet, has apparently proceeded without noticing–or taking into account– this problem.

Meanwhile, no such welding issue was raised with the body of the pressure vessel, which was delivered to the Flamanville site in October 2013 and put in place in January 2014. Nevertheless, the destructive testing program, part of the upper and lower head qualification, was only proposed by Areva to ASN in September 2012. Finally, the tests which revealed the segregated zone were only run in October 2014.

It is unclear for the time being why the industrial process went as far as positioning the pressure vessel in the reactor pit and pursuing the construction around it for many months, when these qualification tests had not even started. This questions both the reason why Areva failed to spot this very important problem at an earlier stage, and the reason why EDF did proceed while qualification was not complete. According to ASN, the reasons for the late testing will be part of the investigation.

Regulatory Issue
Once fully constructed, the EPR reactor in Flamanville-3 would require a final operating license, delivered by ASN under the nuclear regime, to start commercial operation. Prior to that operating license, all pressurized nuclear equipment of the plant, starting with the pressure vessel, must be approved under specific regulations reinforced in 2005. Although previous requirements could have been applied during an exemption period granted in the 2005 ministerial order, ASN made it clear that 2005 regulation fully applies as Areva never asked for such an exemption.

The regulation requires that the manufacturer demonstrates that the pressure vessel meets all the mechanical specifications, of which resilience is an important part. Regarding the parts concerned with the defects, the regulation requires Areva either to prove that the vessel head and bottom meet the mechanical criteria, including an average resilience of 60 J, or to justify that it reaches an equivalent safety level by other means.

Theoretically, there is therefore room for the defective pressure vessel to be qualified through alternative proofing, although the nature and size of the problem will likely make it very difficult, if not impossible. It should also be noted that since vessel head and bottom are not subject to the same operational constraints, the technical assessment could reach different conclusions regarding the acceptability of the two pieces of equipment. In particular, the tube penetrations through the vessel head, needed for the control rods and other instrumentation, introduce further potential weaknesses on welded parts while increasing the mechanical constraints. The lower head, on the contrary, is free of such openings (which is an important change introduced in the design of EPR, compared to previous French reactor designs that had instrumentation penetrations in the bottom plates).

The first step in the reassessment process will be a new series of tests that has already been announced. Areva has proposed a testing program to ASN, which the authority has yet to approve. This will likely consist of further destructive tests on the similar head, which has already been used. These new tests will specifically aim for a more detailed characterization of the defect.

Areva will also need to reinforce the demonstration regarding the transposability of these findings to the actual head and bottom of the Flamanville-3 EPR. Although the program has yet to be discussed, the French Minister of Ecology already announced that the results are expected by October 2015. The ASN will then consider the justification case which Areva will build upon these results. Whether this could be conclusive, one way or the other, and when ASN could come to a final decision are still open questions.

Another open question is the regulatory status of such a decision and whether and how this could be challenged either by the industrial stakeholders or the project opponents, depending on the outcome. In particular, should a positive decision be granted on the basis of a modified justification, this could fall under the regulatory requirement to start a new license, going through a public inquiry, etc. Also, one important issue will be to clarify who would bear the responsibility either to stop the project or to start the reactor in such a context.

Alternative Options

800 protested against the Flamanville reactor in 2011. Photo from Beyond Nuclear.

800 protested against the Flamanville reactor in 2011. Photo from Beyond Nuclear.

If Areva fails to provide a convincing alternative proof to complete the safety case, then the only alternative option is to repair or replace the faulty pieces. The fabrication of a new pressure vessel head would be possible. Regarding the lower head, it is technically very unlikely either to separate it from the whole pressure vessel for replacement or to repair it in situ. Any repair or replacement would therefore almost certainly need the entire pressure vessel to be removed, which would be unprecedented and seems very challenging given the progress of work and lack of space inside the reactor building.

The technical hurdles which any repair or replacement solution for the pressure vessel bottom would need to get over, and the major new safety issues related, come with huge costs and high uncertainty. The feasible alternatives, if any, will raise serious issues of profitability. In other words, economic scenario assessments might show that abandoning the project is cheaper than repair or replacement options, when factors such as the financial costs of further significant delays, or the savings on decommissioning costs if the reactor doesn’t go nuclear, are included.

International impact
The question also arises of the potential impact on other EPR projects where similar defects could be found. There is no particular reason to believe that any vessel head and bottom which has been forged by Japan Steel Works would present the same defect. This is the case of those used for the pressure vessel of the Finnish EPR at Olkiluoto, which are therefore not concerned.

On the contrary, upper or lower heads for other EPRs which have been forged at Le Creusot are expected to be as defective. Although it is still not clear how many and which ones, some of the four parts consisting of the two heads and bottoms of the pressure vessels of Taishan-1 and -2 in China are concerned. One important issue will be the consistency of the technical assessments and the decisions taken by the safety authorities between France and China.

It also remains to be clarified, whether head(s) and bottom(s) already have been forged for the Hinkley Point‐C project in Great Britain or even that of Jaïtapur in India, and if so whether they were forged at Le Creusot.

Yves Marignac, Director of WISE-­Paris
Mail: yves.marignac@wise-­

April 13, 2015


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Why is the US teaming with Russia to gut international nuclear safety standards?

The U.S. is teaming up with the people who brought us Chernobyl. Not in an effort to improve nuclear safety, but to block new safety rules proposed by Europe.

The U.S. is teaming up with the people who brought us Chernobyl. Not in an effort to improve nuclear safety, but to block new safety rules proposed by Europe.

Even after 30 years at NIRS, some days the news is just so appalling that it makes one want to scream. And some days, the actions of the U.S. government–regardless of who is in charge–are just wrong on so many levels that it makes one embarrassed to be an American.

Today is one of those days.
Continue reading

Former top NRC inspector says shut Diablo Canyon

The Diablo Canyon reactors near San Luis Obispo, California

The Diablo Canyon reactors near San Luis Obispo, California

The big news today is that the former top Nuclear Regulatory Commission on-site inspector at the Diablo Canyon reactors, Michael Peck, has recommended to the NRC that those reactors be shut down until their ability to withstand earthquakes is fully assessed.

The weekend’s earthquake in the northern Bay Area of California just adds impetus to Peck’s position.

The irony is that this should have been the big news a year ago: Peck wrote his recommendation–in the form of a formal Differing Professional Opinion–in July 2013. And the NRC still hasn’t taken action, or even responded to it. Continue reading