TOKYO (AP) — The operator of Japan’s destroyed Fukushima Daiichi nuclear power plant demonstrated Tuesday how a remote-controlled robot would retrieve tiny bits of melted fuel debris from one of three damaged reactors later this year for the first time since the 2011 meltdown.

Tokyo Electric Power Company Holdings plans to deploy a “telesco-style” extendable pipe robot into Fukushima Daiichi No. 2 reactor to test the removal of debris from its primary containment vessel by October.

That work is more than two years behind schedule. The removal of melted fuel was supposed to begin in late 2021 but has been plagued with delays, underscoring the difficulty of recovering from the magnitude 9.0 quake and tsunami in 2011.

During the demonstration at the Mitsubishi Heavy Industries’ shipyard in Kobe, western Japan, where the robot has been developed, a device equipped with tongs slowly descended from the telescopic pipe to a heap of gravel and picked up a granule.

TEPCO plans to remove less than 3 grams (0.1 ounce) of debris in the test at the Fukushima plant.

“We believe the upcoming test removal of fuel debris from Unit 2 is an extremely important step to steadily carry out future decommissioning work,” said Yusuke Nakagawa, a TEPCO group manager for the fuel debris retrieval program. “It is important to proceed with the test removal safely and steadily.”

About 880 tons of highly radioactive melted nuclear fuel remain inside the three damaged reactors. Critics say the 30- to 40-year cleanup target set by the government and TEPCO for Fukushima Daiichi is overly optimistic. The damage in each reactor is different, and plans must accommodate their conditions.

Better understanding the melted fuel debris from inside the reactors is key to their decommissioning. TEPCO deployed four mini drones into the No. 1 reactor’s primary containment vessel earlier this year to capture images from the areas where robots had not reached.

The DOE announced that the Hanford Integrated Tank Disposition Contract (ITDC) was awarded to Hanford Tank Waste Operations & Closure, LLC (H2C), which is a joint venture led by a BWXT subsidiary and includes subsidiaries of Amentum and Fluor.

The scope of the ITDC includes operation of Hanford tank farm facilities, eventual operation of the Waste Treatment and Immobilization Plant, and responsibility for other core functions such as project management, security and emergency services, business performance, and environment, safety, health, and quality.

Responsible for the federal government’s cleanup of the legacy of more than 40 years of producing plutonium through the 1980s, DOE is transforming the Hanford Site near Richland, Washington back into an operations mode to treat tank waste from the production era. More information is available from the DOE’s Office of Environmental Management.

The use of robots is increasingly commonplace, and according to Sellafield, they recently became the first to use a light detection and ranging (LiDAR) laser scanning device on remote-operated vehicles (ROV) in a high radiation environment.

This allowed the robot to navigate and build a 3D image of the hazardous area removing the need for humans to enter.

Calvin Smye, ROV equipment engineer, Sellafield Ltd said: “Everything we are using is off the shelf but by adding different payloads, like a LiDAR sensor and a radiation monitor, we are adapting them to deliver for our business.

“Since the introduction of this technology we’ve really been at the forefront of testing it and adjusting it to our needs…”

Spot in the spotlight

The robot fitted with LiDAR was indeed Spot the robot dog, a regular fixture at many Sellafield jobs and inspections.

Spot’s capabilities were shared recently during a live demonstration at Calder Hall, a building constructed in the 1950s where asbestos is a known hazard.

AtkinsRéalis recently utilized Spot to conduct an inspection to map how best to conduct clean-up operations. The inspection was live-streamed via Spot’s on-board camera.

According to Sellafield, these robots are now being used across other Nuclear Decommissioning Authority sites in the UK.

Also, the team is using IPEK crawler robots to inspect sewer pipes and exploring the use of ROVs to detect potentially dangerous gases in work areas before humans are sent in.

Deon Bulman, ROV equipment program lead, Sellafield Ltd said: “The adoption of new technology is progressing at pace at Sellafield as people start to see the benefits…If we can do one task that removes the need for a person to enter a hazardous area, that’s a win.”

Added Rav Chunilal, head of robotics and artificial intelligence at Sellafield Ltd: “These cutting-edge robots allow us to access dangerous and challenging areas remotely, removing humans from harm’s way and saving time and costs for maintenance and inspections.”

According to the National Nuclear Laboratory, Sellafield has been home to nuclear materials in one form or another since 1947. The site was part of the British nuclear weapons program and then became home to four nuclear reactors for the purpose of generating nuclear energy.

Now, after more than half a century of nuclear activity, the site is being decommissioned.

Originally published by Pamela Largue in Power Engineering International.

Holtec International said it would again apply for the U.S. Department of Energy’s $6 billion Civil Nuclear Credit (CNC) program to potentially reopen Palisades nuclear plant in Michigan.  

DOE rejected the funding request in November despite support from top state lawmakers like Michigan Gov. Gretchen Whitmer.

“The repowering of Palisades is of vital importance to Michigan’s clean energy future,” said Holtec International in a statement posted to Twitter. The company cited “supportive feedback received” in its decision to apply for the next round of CNC funding.

Holtec said its team will remain focused on decommissioning, with a focus on managing the spent fuel removal from the spent fuel pool to dry cask storage.

Today we announced our intent to reapply to the @ENERGY Civil Nuclear Credit Program to potentially restart @PalisadesEnergy https://t.co/VXwuuQT8CA

— Holtec International (@holtecintl) December 19, 2022

Holtec bought the 805 MW Palisades in May to decommission it and applied for CNC funding. The plant, formerly owned by Entergy, was shut down last spring after generating electricity for more than 50 years.

The company previously said it understood that its bid to reopen the shuttered nuclear plant would be a challenge, as the reversal in operating status would have been a first for the industry.

ClearView Energy Partners, a nonpartisan research group, said in September that Palisades’ closure was “likely to be permanent.” Palisades was out of nuclear fuel, faced a control rod drive seal issue that needed to be fixed and likely needed a new company to operate it, as well as a buyer for the power it generates, ClearView told Reuters.

The U.S. Department of Energy has awarded $2.8 million to a coalition of partners who will research fuel management options for next-gen nuclear reactors.

EPRI will lead the team, which also includes Oak Ridge National Laboratory (ORNL), Southern Company and Deep Isolation. The funding comes from DOE’s Advanced Reactor Research Projects Agency – Energy (ARPA-E).

Specifically, the two-year project aims to expand the available options of nuclear fuel management by creating a tool to optimize processes for the recovery of uranium from used nuclear fuel. The scope of the project would include an at-scale study for market readiness of some of these techniques.

EPRI will provide project management and expertise in advanced reactor development, ORNL will provide technical expertise in nuclear fuel cycles and system modeling for developing the tool, Southern Company will provide real-world data and their experience in shepherding new technology from the laboratory to full-scale commercial deployment and Deep Isolation will assist with technical expertise in the disposal of used fuel in deep borehole repositories approximately a mile underground.

“This project is at the heart of two of our focus areas at ORNL — advancing the next generation of nuclear technology to meet the nation’s energy needs and climate goals while reducing the demand on waste generation storage and ultimate disposal,” said Andy Worrall, section head of Integrated Fuel Cycle research at ORNL.

The projects were selected to develop technologies to advance UNF recycling, reduce the volume of high-level waste requiring permanent disposal, and provide safe domestic advanced reactor fuel stocks. 

UNF can be recycled to make new fuel and byproducts that support the deployment of nuclear energy. 

Once discharged from a nuclear reactor, the UNF is initially stored in steel-lined concrete pools surrounded by water. It is later removed from those pools and placed into dry storage casks with protective shielding. Most of the nation’s used fuel is stored at more than 70 reactor sites across the country. 

Projects funded through the Converting UNF Radioisotopes Into Energy (CURIE) program are expected to enable secure, economical recycling of UNF and substantially reduce the volume, heat load, and radiotoxicity of waste requiring permanent disposal. These efforts also are intended to provide a fuel feedstock for advanced reactors.  

Led by DOE’s Advanced Research Projects Agency-Energy (ARPA-E), the following teams were selected to develop separation technologies with improved proliferation resistance and safeguards technologies for fuel recycling facilities, and perform system design studies to support fuel recycling:  

Argonne National Laboratory will develop a highly efficient process that converts 97% of UNF oxide fuel to metal using stable next-generation anode materials. (Award amount: $4,900,000) 

Argonne National Laboratory will develop, produce, and test a suite of compact rotating packed bed contactors for used nuclear fuel reprocessing. (Award amount: $1,520,000) 

Curio will develop and demonstrate steps of the team’s UNF recycling process—known as NuCycle—at the laboratory scale. (Award amount: $5,000,000) 

EPRI will develop a recycling tool intended to address the coupled challenges of nuclear fuel life-cycle management and advanced reactor fuel supply. (Award amount: $2,796,545) 

GE Research will develop a revolutionary safeguards solution for aqueous reprocessing facilities. (Award amount: $6,449,997)  

Idaho National Laboratory will design, fabricate, and test anode materials for electrochemically reducing actinide and fission product oxides in UNF. (Award amount: $2,659,677) 

Mainstream Engineering will develop a vacuum swing separation technology to separate and capture volatile radionuclides, which should lower life cycle capital and operating costs, and minimize waste that must be stored. (Award amount: $1,580,774) 

NuVision Engineering will design, build, and commission an integrated material accountancy test platform that will predict post-process nuclear material accountancy to within 1% uncertainty in an aqueous reprocessing facility. (Award amount: $4,715,163) 

University of Alabama at Birmingham will develop a single-step process that recycles UNF by recovering the bulk of uranium and other transuranics from UNF after dissolution in nitric acid. (Award amount: $1,844,998)  

University of Colorado, Boulder will advance technology capable of high-accuracy, substantially faster measurements of complex UNF mixtures. (Award amount: $1,994,663) 

University of North Texas will develop a self-powered, wireless sensor for long-term, real-time monitoring of high-temperature molten salt density and level to enable accurate safeguarding and monitoring of electrochemical processing of UNF. (Award amount: $2,711,342)  

University of Utah will develop a pyrochemical process for efficiently converting UNF into a fuel feedstock suitable for sodium-cooled fast reactors or molten-salt-fueled reactors. (Award amount: $1,454,074)  

The U.S. Army Corps of Engineers chose Westinghouse to decommission and dismantle the mothballed SM-1A nuclear plant at Fort Greely in Alaska.

The $103 million job is expected to take six years to complete, with work expected to begin in 2023.

SM-1A was a single-loop, 20.2 MW-thermal pressurized water reactor that used highly enriched uranium dioxide fuel to generate 2,000 kW of electrical power and 37,850 pounds of extraction steam per hour. The design was based on the concept of the SM-1 reactor at Fort Belvoir, Virginia, a prototype for stationary medium-power plants.

Construction began in 1958 and was completed in 1962. It was shut down in 1972 as it was more expensive to operate than a diesel plant.

Much of the reactor’s primary system components were dismantled, and components inside the vapor container were encased in concrete and a mixture of grout, soil and sand. Waste generated during the initial deactivation activities was placed in the spent fuel pit and waste tanks pit. These pits were then filled and capped with reinforced concrete.

Located around 100 miles southeast of Fairbanks, SM-1A’s primary mission was to supply electrical power and heating for buildings and facilities at Fort Greely. It was also used as an in-service test facility to understand how the equipment would function in an arctic environment.

The plant was also used to study the economics of operating a nuclear plant as compared to a conventional oil-fired system in a remote setting, where fuel costs are high and refueling logistics are challenging.

Palisades, located in Covert Michigan, shut down in May after more than 50 years in service. The plant had just completed a production run of 577 straight days of operation. 

The sale of the Palisades plant completes what Entergy said was its planned exit from the nuclear merchant power business, and follows the closure and sale of the Vermont Yankee, Pilgrim and Indian Point plants and the sale of the operating James A. Fitzpatrick plant.

Entergy first announced the planned closure of Palisades in 2016 to focus on its utility operations in the Gulf South. Under terms of the sale, Holtec International agreed to hire around 260 current Palisades employees for the first phase of decommissioning. Another 180 employees at Palisades will be let go. Entergy said that more than half of those employees are eligible for retirement.

Big Rock Point, located in Charlevoix Michigan, shut down in 1997 and was decommissioned in the early 2000’s. Only the used fuel remains at the Big Rock Point site. 

The Palisades decommissioning project is intended to have a 19-year timeline, with the projected completion of transfer of fuel from wet to dry storage by 2025. The balance of the dismantling and decommissioning operations is expected to be aligned with ongoing work at Oyster Creek, Pilgrim and Indian Point sites. 

In accordance with NRC rules, decommissioning must be completed within 60 years of the plant ceasing operations. The nuclear site owner (or licensee) may choose from three decommissioning strategies: DECON, SAFSTOR or ENTOMB. Historically, some nuclear plant owners have selected to place the plant in SAFSTOR, an option that allows the nuclear plant to be shuttered for several decades before decommissioning and site restoration is completed.

Completion of Palisades decommissioning expected to make the 400+ acre site fit for commercial/industrial use, except for a parcel of land where the dry storage casks will be stored.  Holtec said it hopes to ship the storage canisters to its proposed consolidated interim storage facility in Southeastern New Mexico, called HI-STORE CISF, which is undergoing the final stage of licensing review by the Nuclear Regulatory Commission (NRC). 

In mid-July, the NRC issued its final environmental review of the project. The review found no environmental reasons that would prevent Holtec from building the multibillion-dollar facility to temporarily store tons of spent nuclear fuel from commercial power plants around the nation. A safety review of the proposed project is still pending by the NRC.

Holtec is now the licensed operator and owner of the Oyster Creek and Pilgrim sites. A license transfer application has been submitted for Entergy’s Indian Point Energy Center.

Part of the decommissioning process involves moving spent nuclear fuel from the spent fuel pool to an onsite dry storage facility called an Independent Spent Fuel Storage Installation. Holtec said that while this process used to five or more years after reactor shutdown, its use of dry storage systems allows the transfer to be done in fewer than three years. It said that other decommissioning activities can be started sooner and performed more efficiently.

The Holtec web site said that the financial performance of the decommissioning trust fund is “inextricably tied” to the financial markets. It said that a “sharp and sustained slump” in the market “certainly has the potential” to disrupt the pace of the decommissioning work. It said that funds are managed in an effort to ensure that short-term expenditures are invested in bonds and other more stable financial instruments, to limit any impact from a market downturn.

Norsk Nukleær Dekommisjonering (NND) selected a joint venture between Dallas-based Jacobs and Multiconsult Norge AS to plan the decommissioning of Norway’s nuclear fleet.

The initial contract will focus on two research sites – the nuclear fuel and materials testing reactor at Halden and the JEEP-II neutron scattering facility at Kjeller – which were shut down in 2018 and 2019, respectively.

NND estimates the total value of the six-year award at up to $100 million (NOK 1 billion).

The scope includes engineering concept design and planning of new facilities, upgrading of existing nuclear and non-nuclear facilities and supporting with technical documentation, as well as preparing safety cases to meet ownership and operating license requirements.

The overall program for used fuel treatment and decommissioning of the Halden and Kjeller reactors is expected to cost about $1.96 billion (NOK20 billion) and take 20-25 years.

Palisades nuclear plant in Michigan shut down 11 days earlier than planned.

Control room operators removed the 805 MW plant’s nuclear reactor from service on May 20. The plant was originally scheduled to permanently shut down on May 31.

Entergy said operators made the decision to shut down the plant early due to the performance of a control rod drive seal. After used fuel is removed from the reactor, the facility will be transferred to Holtec International for decommissioning, per an agreement approved by the Nuclear Regulatory Commission (NRC) in December 2021. The license transfer is scheduled for this summer.

Holtec’s filings detail its plan to complete the dismantling, decontamination, and remediation of Palisades to NRC standards by 2041. That is more than 40 years sooner than if Entergy continued to own the facility and selected the maximum 60-year NRC SAFSTOR option for decommissioning.

The shutdown of Palisades coincides with the expiration of the plant’s 15-year power purchase agreement with Consumers Energy. The retirement was first announced in 2017.

Following the retirement announcement in 2017, Entergy made several commitments to plant employees. Any employee willing to relocate to another Entergy facility would be provided a job, if they were qualified.

The utility said approximately 130 employees accepted a job offer within the company’s southern service territory. As part of Entergy’s agreement with Holtec International, the new owner of the plant post-shutdown will hire approximately 260 current Palisades employees for the first phase of decommissioning.

Approximately 180 employees at Palisades will separate from the company, Entergy said. More than half of those employees are retirement eligible.

Palisades, which began commercial operation in 1971, generated about 800 MW at capacity.