New proposal suggests removing Fukushima plant’s melted nuclear fuel from side — The Mainichi

” A method to remove melted nuclear fuel debris on the bottom of the containment vessels of Fukushima No. 1 Nuclear Power Plant’s first, second and third reactors from the side was proposed by the Nuclear Damage Compensation and Decommissioning Facilitation Corporation (NDF) on July 31.

Hajimu Yamana, head of the NDF, which is tasked with considering how to remove fuel debris from the reactors, for the first time explained the organization’s specific method proposal to the heads of local governments at a countermeasures for the decommissioning and handling of the contaminated water council meeting held in Iwaki, Fukushima Prefecture.

The method would focus on prioritizing the removal of debris from the bottom of the vessels from the side, using robotic arms and other remote devices while flushing water over the debris. However, ways to block radiation and countermeasures against the scattering of airborne radioactive dust still remain unsolved. The central government and Tokyo Electric Power Co. (TEPCO) plan to finalize their policy to remove the debris and amend the decommission schedule in September.

In all three of the reactors, contaminated water has collected at the bottom of the containment vessels. The NDF had previously considered a “flooding method” that would fill the containment vessels completely with water to block radiation from leaking. However, measures to repair the containment vessels and prevent leakage of the radioactive water would be difficult, so the plan was put aside for having “too many issues.” “

by The Mainichi

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Fukushima Bill — Asia Times

” Six years after Japan’s Fukushima nuclear accident three global nuclear corporations are fighting for their very survival.

The bankruptcy filing by Westinghouse Electric Co. and its parent company Toshiba Corp. preparing to post losses of ¥1 trillion (US$9 billion), is a defining moment in the global decline of the nuclear power industry.

However, whereas the final financial meltdown of Westinghouse and Toshiba will likely be measured in a few tens of billions of dollars, those losses are but a fraction of what Tokyo Electric Power Co. (Tepco) is looking at as a result of the Fukushima nuclear disaster.

If the latest estimates for the cost of cleaning up the Fukushima plant prove accurate, Tepco faces the equivalent of a Toshiba meltdown every year until 2087.

In November 2016, the Japanese Government announced a revised estimate for the Fukushima nuclear accident (decommissioning, decontamination, waste management and compensation) of ¥21.5 trillion (US$193 billion) – a doubling of their estimate in 2013.

But the credibility of the government’s numbers have been questioned all along, given that the actual ‘decommissioning’ of the Fukushima plant and its three melted reactors is entering into an engineering unknown.

This questioning was borne out by the November doubling of cost estimates after only several years into the accident, when there is every prospect Tepco will be cleaning up Fukushima well into next century.

And sure enough, a new assessment published in early March from the Japan Institute for Economic Research, estimates that total costs for decommissioning, decontamination and compensation as a result of the Fukushima atomic disaster could range between ¥50-70 trillion (US$449-628 billion).

Rather than admit that the Fukushima accident is effectively the end of Tepco as a nuclear generating company, the outline of a restructuring plan was announced last week.

Tepco Holdings, the entity established to manage the destroyed nuclear site, and the Nuclear Damage Compensation and Decommissioning Facilitation Corporation (NDF) are seeking ways to sustain the utility in the years ahead, confronted as they are with escalating Fukushima costs and electricity market reform.

The NDF, originally established by the Government in 2011 to oversee compensation payments and to secure electricity supply, had its scope broadened in 2014 to oversee decommissioning of the Fukushima Daiichi plant on the Pacific Ocean coast north of Tokyo.

The latest restructuring plan is intended to find a way forward for Tepco by securing a future for its nuclear, transmission and distribution businesses. If possible in combination with other energy companies in Japan.

But the plan, already received less than warmly by other utilities rightly concerned at being burdened with Tepco’s liabilities, is premised on Fukushima cost estimates of ¥21.5 trillion — not ¥50-70 trillion.

To date Tepco’s Fukushima costs have been covered by interest-free government loans, with ¥6 trillion (US$57 billion) already paid out. Since 2012 Tepco’s electricity ratepayers have paid ¥2.4 trillion to cover nuclear-related costs, including the Fukushima accident site.

That is nothing compared to the costs looming over future decades and beyond and it comes at a time when Tepco and other electric utilities are under commercial pressure as never before.

The commercial pressure comes from electricity market reform that since April 2016 allowed consumers to switch from the monopoly utilities to independent power providers.

Prior to the deregulation of the retail electricity market, Tepco had 22 million customers. As the Tepco president observed late last year “The number (of customers leaving Tepco) is changing every day as the liberalization continues … We will of course need to think of ways to counter that competition.”

Countering that competition shouldn’t mean rigging the market, yet Tepco and the other utilities intend to try and retain their decades long dominance of electricity by retaining control over access to the grid. This is a concerted push back against the growth of renewable energy.

Current plans to open the grid to competition in 2020, so called legal unbundling, are essential to wrest control from the big utilities.

The message of unbundling and independence, however, doesn’t seem to have reached the Ministry of Economy, Trade and Industry (METI) that oversees the electricity industry.

Current plans would allow Tepco to establish separate legal entities: Tepco Fuel & Power (thermal power generation), Tepco Energy Partner (power distribution) and Tepco Power Grid (power transmission).

Tepco Holdings will retain their stock and control their management, meaning the same monopoly will retain control of the grid. Where Tepco leads, the other nine electric utilities are aiming to follow.

Leaving the grid effectively still under the control of the traditional utilities will throw up a major obstacle to large scale expansion of renewable energy sources from new companies.

Such businesses will be ‘curtailed’ or stopped from supplying electricity to the grid when the large utilities decide it’s necessary, justified for example to maintain the stability of the grid.

The fact that ‘curtailment’ will be permitted in many regions without financial compensation piles further pain onto new entrants to the electricity market, and by extension consumers.

Further, METI plans to spread the escalating costs of Fukushima so that other utilities and new power companies pay a proportion of compensation costs. METI’s justification for charging customers of new energy companies is that they benefited from nuclear power before the market opened up.

The need to find someone else to pay for Tepco’s mess is underscored by the breakdown of the Fukushima disaster cost estimate in November.

When put at ¥22 trillion estimate, ¥16 trillion is supposed to be covered by Tepco. The Ministry of Finance is to offer ¥2 trillion for decontamination, and the remaining ¥4 trillion is to be provided by other power companies and new electricity providers.

The question is how does Tepco cover its share of the costs when it’s losing customers and its only remaining nuclear plant in Japan, Kashiwazaki Kariwa (the worlds largest), has no prospect of restarting operation due to local opposition?

What happens when Fukushima costs rise to the levels projected of ¥50-70 trillion?

The policy measures being put in place by Tepco, other utilities and the government suggests that they know what is coming and their solution for paying for the world’s most costly industrial accident will be sticking both hands into the public purse. ”

by Shaun Burnie, Asia Times

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Editorial: New technology to help resolve Fukushima nuclear crisis needs gov’t backing — The Mainichi; South China Morning Post

” The Japanese government has once again revised the work schedule for decommissioning reactors at the triple-meltdown-stricken Fukushima No. 1 nuclear plant. The last major change was in June 2013, and this one pushes back the removal of spent fuel rods from the fuel pools of the No. 1-3 reactors by as much as three years. The delay is due to unexpected difficulties preventing the escape of airborne radioactive contaminants during decontamination and wreckage clearing work.
Decommissioning reactors at the heart of one of the world’s worst nuclear disasters is of course bound to be extremely difficult, and this reality is coming into sharp relief.

Progress on dismantling the Fukushima reactors has a direct bearing on both overall regional disaster recovery and when local residents will be able to finally return home. As such, we call on both the government and plant operator Tokyo Electric Power Co. to develop a reactor decommissioning strategy with a solid strategic foundation, and to thoroughly release information on the process.
The latest revisions to the decommissioning work schedule were based on the basic principle of putting the safety of locals and plant workers first. The first version of the work schedule was obsessed with speed. The result was a rash of worker injuries and deaths and other problems that ended up causing progress to be delayed. Rather than making speed top priority, it’s more important to carefully and surely reduce the various risks related to the Fukushima plant.

The jobs with the highest priority under the work plan’s latest iteration are the recovery of nuclear fuel rods from the fuel pools, and dealing with the vast quantities of radioactively contaminated water produced at the plant. Though these tasks are certainly important, the most difficult hurdle in the decommissioning process will be extracting the melted fuel from inside the stricken reactor vessels. Under the new schedule, this is set to start on just one of the reactors sometime in the year 2021.

That’s some six years away, but the path from here to there remains foggy at best. First of all, no one knows for sure exactly what state the fuel is in or even where it is in the reactor housings.

The method for getting the fuel out is also up in the air. At first, planners thought it best to fill the reactor vessels with water to suppress the intense radiation when the operation began. This fell by the wayside, however, when it turned out to be difficult to identify damaged spots on the reactor vessels and stop water from escaping. Now, an in-air removal method is being considered, though entirely new equipment will need to be developed to perform the operation in the highly radioactive environment while at the same time preventing contaminants from getting airborne.

There are a number of research institutes and universities across Japan that are receiving government support to invent the technology needed for this reactor decommissioning work. The “control tower” for these efforts is the Nuclear Damage Compensation and Decommissioning Facilitation Corp. (NDF), created by the government in August last year. The corporation is tasked with overseeing each project from basic research through to practical application, and to optimize the development process.

The NDF, however, has just 35 or so technical staff. It’s an open question whether the NDF can exercise effective oversight for such a wide program with so few people. The government is trying to enhance the corporation’s functions, but there have been no concrete measures forthcoming so far. At this rate, might the 30-40 year target to decommission the Fukushima reactors come under serious pressure?

Prime Minister Shinzo Abe has said more than once that “the national government stands on the front lines” of the efforts to deal with the decommissioning work. Then more than ever, the government must create a system to provide full and complete support for the technology research and development projects needed to finally bring the nuclear crisis to an end. ”

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Also read a similar article by the South China Morning Post: “Scale of Fukushima clean-up revealed as decommissioning ‘road map’ is revised

Japan to start Fukushima fuel debris retrieval in 2021 — World Nuclear News

” Japan expects to start the retrieval of fuel debris from the Fukushima Daiichi nuclear power plant in 2021, the executive director of the Nuclear Damage Compensation and Decommissioning Facilitation Corporation (NDF) said yesterday. Three of the plant’s six reactors suffered core meltdowns in the March 2011 accident, leaving melted nuclear fuel debris on the floor of their containment vessels.

NDF was established in September 2011 by the Japanese government and the country’s nuclear power plant operators to manage a fund to support operators in providing compensation to victims of nuclear accidents. Although established following the Fukushima Daiichi accident, NDF will continue to be maintained in the future as part of the Japanese nuclear liability regime.

“We expect to select the retrieval method within the next few years, after which detailed design and mock-up tests will follow,” NDF executive director Yasuharu Igarashi told delegates at the VII Atomexpo conference in Moscow. The event was hosted by Russian state nuclear corporation Rosatom. “For the start of retrieval of fuel debris, we are now thinking 2021,” Igarashi said.

NDF has identified three “priority methods” for retrieving highly radioactive nuclear fuel debris in three reactors at Tokyo Electric Power Company’s (Tepco’s) Fukushima Daiichi plant. They are: submersion; partial submersion top access; and partial submersion side access. The first two rely on the removal first of core internals above fuel debris, while the third requires that the reactor pressure vessel pedestal exterior component inside the primary containment vessel (PCV) and interference have first been removed.

The submersion method would remove the debris in a submerged condition, with the containment vessel filled with water to shield against radiation and prevent the spread of radioactive materials during the retrieval process. The reactor damage would need to be accurately identified and repaired before water is poured in. Partial submersion means that water would only be used when the debris has been separated from the vessel floor. The debris would be removed from either the top or the side of the vessel. This method would require continuous cooling of the retrieved debris and measures to prevent radioactive materials from scattering.

Tepco started inspections of unit 1 of the plant in April using robots mounted with cameras and radiation-measuring equipment. The shape-changing robot began surveying conditions within the PCV of the damaged unit on 10 April. However, the robot stopped working before completing its mission. The robot was developed by the International Research Institute for Nuclear Decommissioning and Hitachi-GE Nuclear Energy to investigate hard-to-access areas of the plant. Tepco later sent in a second robot On April 20. The company said that it had decided not to try to retrieve a second robot dispatched inside the unit to avoid it becoming blocked and impeding future missions.

Igarashi said that NDF is following five “guiding principles” for risk reduction in its strategic plan for decommissioning the Fukushima Daiichi plant. They are that the plan is safe, proven, efficient, timely and “field-oriented”, meaning it is based on the actual conditions of the site and structures.

“The decommissioning of the Fukushima Daiichi nuclear power plant is a continuous risk reduction activity to protect people and the environment from the risk of radioactive materials resulting from the severe accident,” he said. “A risk reduction strategy along a mid- to long-term timeline will be designed in NDF’s strategic plan.”

The structure of NDF’s risk management strategy is to be completed by 2017, he said.

In addition to fuel debris retrieval, the strategic plan will also include a policy for waste management involving storage, processing and disposal methods, he said.

NDF has reviewed international standards for waste management, he said, and the International Atomic Energy Agency’s General Safety Requirements Part 5 and Specific Safety Requirements-5 are “important references”. ”

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