Thirty-three years have passed since the explosion at the power unit four of the Chornobyl nuclear power plant. The territory within a radius of thirty kilometers became a zone of alienation. Gradually, it turns into a radiation-ecological biosphere reserve. Lands within a radius of ten kilometers from the plant itself will never become habitable. However, they are trying to return to the state property, moreover, to make it investment-attractive. Meanwhile, new safe confinement (NSC) or Arch is planned to be commissioned later this year. This means the beginning of the next stage in transforming the Shelter into an environmentally safe system: dismantling the unstable structures of the old sarcophagus.
The Arch can be launched already this year
On April 22 the test continuous operation of the New Safe Confinement had begun. It took place in three stages and included testing equipment and testing staff skills.
The first stage concerned the testing of the main cranes inside the Arch.
The second stage involved testing of crane girders, moving two cranes over the roof of the Shelter. After that, they conducted a conditional disassembly of individual structures, which were installed to stabilize the first sarcophagus.
During the third stage, work on the treatment of solid radioactive waste was carried out: its fragmentation, decontamination, loading into special containers, its further transfer into container carriers and delivery to the industrial complex for processing solid radioactive waste.
On the morning of April 25, we noted the successful completion of the test operation. This was voiced at the opening of the IV International Conference INUDECO 2019.
Now they have to prepare a package of documents on the results of the trial operation of the Arch, after which the station will receive a permit for pilot operation of the confinement, later ‒ a license. Approximately these procedures can last about a year. After them, the NSC will begin operating to dismantle the first unstable structures. Its completion according to a preliminary plan is scheduled for 2023. It was then that the life of the structures that were built to stabilize the old sarcophagus expired. Dmytro Stelmakh, the Head of the Strategic Planning Department of the State Specialized Enterprise “Chornobyl Nuclear Power Plant” (SSE CNPP), suggested that the start of operation is possible already this year.
Recall, the construction of Arch started in 2007 by the joint forces of the SSE CNPP and a consortium of foreign companies Novarka. In 2016, the construction was stretched over the Shelter, they began to install the necessary equipment. The trial operation took place only this year.
After the explosion in 1986, scientists and builders were making the Shelter object during 206 days. Partially, it relies on the individual parts of the 4th power unit, the lifetime of which is not defined. At the same time, under the influence of a number of external factors, there is a high risk of their destruction and the further collapse of the Shelter. The sarcophagus itself was built in a short time, in conditions of increased radiation danger, because of which this object does not meet construction standards. Dmytro Stelmakh talked about this, arguing the need for further dismantling of the first sarcophagus. Analysis of the design will be carried out in reverse order. “The project is designed for ten years, the total cost of the project, meaning capital investments, may be more than five billion UAH. The relevant tender procedures have already begun,” Dmytro Stelmakh said.
Doubts about the safety of the work and its feasibility were voiced by the former head of the Shelter object (from 1995 to 2002) Valentyn Kupny during the breakout sessions at the INUDECO conference. In particular, he said that, according to the schedule, the Ark had to be erected in mid-2017, instead, work was accelerated and implemented in 2016. Therefore, according to Valentyn Kupny, the workpeople received an amount of radiation that is predominantly the one that was received by workers in 2008, when they were in close proximity to the most dangerous Shelter zones for stabilization. Therefore, he made a proposal to analyze the possible doses received during work in 2016-2017 and take them into account during further dismantling actions.
“Dismantling unstable structures, in fact, says nothing. In effect, they are going to open the central hall and the reactor shaft under the Arch. The result will be an open arrangement of highly reactive waste. Dust ejection will happen and the situation under the arch will deteriorate significantly, ” Valentyn Kupny commented.
In addition, he noted: the Arch created the so-called “greenhouse” conditions for the sarcophagus. The influence of the external environment has significantly decreased. Then he proposed an alternative option of “procumbent stabilization”. This term originated in 2008, during the stabilization work. Then, according to Valentyn Kupny, they stabilized eight dangerous nodes. Therefore, in the future, we can continue to work with the Shelter.
Dmytro Stelmakh assured that the safety analysis of the work will be carried out. This will be done at the design stage. If it turns out that the planned fails to implement safely, further decisions on actions will not be taken. And most likely, if necessary, they will proceed to stabilization works. However, according to Dmytro Stelmakh, this cannot last forever. Therefore, dismantling is inevitable. However, with the help of new equipment, it is possible to dismantle in safe conditions for personnel. But in any case, this issue will be examined.
From the Exclusion Zone to the zone of alternative energy sources
The alienation zone, especially around the station, will never become suitable for carrying out any economic activity. This was stated by the Deputy Head of the Strategic Planning Department of the Chornobyl NPP Viktor Kuchynsky. After it was decided to decommission the power plant, they began to look for ways to use the area around.
“There was a legal situation: a regulatory document written for the decommissioning of a normal nuclear power plant indicates that the main purpose of the activity is to return the territory for reuse. But how to do it in the conditions of the Chornobyl NPP ‒ at that time, we could not find an approach,” Viktor Kuchynsky said. The solution was found in 2008. Then they formed the concept of development and further integration in the country’s nuclear industry.
“We see ourselves as a platform for the centralized management and processing of all radioactive waste that accumulates at all nuclear power plants in Ukraine. At nuclear power plants, they do the initial processing, then they transport them to us, we do the final processing and disposal.” However, in order for this concept to work, it is necessary, among other things, to provide additional electricity.
Last year, they began to work in a new direction, not related to nuclear power, but it concerns alternative sources of energy: solar panels and wind turbines. The advantage of this decision is that, firstly, it does not contradict the current legislation. Secondly, it is technology “without people”, that is, it does not provide for attracting a person. “Thus, we get pragmatic reuse and this territory is involved in the state’s economy,” Viktor Kuchynsky commented.
At present, there is already a small pilot station for the use of alternative energy sources on the territory of the Chornobyl NPP. It was built last year and now it produces one megawatt of energy, which is sent to the general network. For comparison, the Chornobyl NPP itself consumes 10 megawatts of energy. The plans are to expand the territory for the installation of solar panels and wind turbines, in particular, to use a cooling pond and lands, adjacent to the station. The power lines of the Chornobyl NPP produced by alternative means of energy will be transported to clean areas and consumed by the population. “We became the first nuclear power plant that produces alternative electric power,” Viktor Kuchynsky concluded.
Dmytro Stelmakh said that the Chornobyl NPP specialists developed a state investment project in order to have a reason to attract foreign investments and investments from private entrepreneurs to the full-scale implementation of the project. Now it is implemented partially for public funds. One substation will be completed next year, the development project of the second, northern one will start this year.
Now Chornobyl is in the process of decommissioning. It finally ceased to function in 2000 (by order of President Leonid Kuchma, the third power unit was stopped. The first was stopped in 1996, the second in 1991, after a fire in the engine room). Today, according to Dmytro Stelmakh, the units are freed from spent nuclear fuel. It is located in the storage of spent nuclear fuel of a wet type. Within 10 years, it will be transferred from there to a new dry type storage facility.
Despite the fact that the station does not work in a broad sense, some of the equipment is still functioning, the staff of the station monitors its work.
INUDECO is the annual international conference on the problems of decommissioning nuclear power facilities and restoring the environment. This year it took place for the fourth time, and for the first time on the territory of the Chornobyl NPP. In 2019, 150 scientists and representatives of nuclear power plants took part in it, including participants from Japan, Spain, France, Denmark, and Norway. The essence of the conference is the exchange of experience on the decommissioning of nuclear facilities, the management of spent fuel, technologies, and post-disaster recovery (this is a report from the Japanese scientists about the accident at Fukushima station 1). At the fourth INUDECO conference, the meetings were held in four sections, in particular, they spoke about the state of the Shelter object, possible risks of its dismantling, monitoring the situation inside the object; presentation of monitoring technologies and control systems; restoration of the territory after the catastrophe and new prospects for the restoration of ecology.
After the explosion at the reactor, in the Polissya hotel in Prypyat, the headquarters held a meeting during which they decided what to do next. These were the conditions of heightened risk, uncertainty, and one can assume, unawareness of the full scale of the tragedy. Then the decision was made quickly, and thanks to the construction of the Shelter at an accelerated pace, we managed to win thirty years in search of further solutions.
The Arch gave humanity a hundred years. At the current scientific meetings, there is a place for discussions, talking, getting new ideas and solutions to related problems. There is an opportunity to exchange international experience and time to work on the bugs. And there is a hope that the zone will reborn. At least, in the context of returning to the country’s economy.
By Dina Vong