Ukraine informed the International Atomic Energy Agency (IAEA) on 13 March that Ukrainian specialist teams had succeeded in repairing a power line needed to resume external electricity supplies to the Chernobyl Nuclear Power Plant, four days after they were completely lost at the Russian-controlled site, director general Rafael Mariano Grossi said.

Grossi received the news from the head of Ukraine’s nuclear utility Energoatom, Petro Kotin, who said the specialists had fixed one of two damaged lines and would now be able to deliver all required off-site power to the site, where various radioactive waste management facilities are located following the 1986 accident.

Ukraine’s regulator, SNRIU, separately informed the IAEA that the power supply line was restored at 18:38 CET by the repair personnel of Ukrenergo, the country’s transmission system operator. The Chernobyl NPP continues to work on back-up diesel generators and will be reconnected to the Ukrainian electricity grid the next morning, it said.

The nuclear power plant's disconnection from the grid last week did not have a critical impact on essential safety functions at the site as the volume of cooling water in its used fuel facility was sufficient to maintain heat removal without a supply of electricity. “This is a positive development as the Chernobyl NPP has had to rely on emergency diesel generators for several days now,” Grossi noted. “However, I remain gravely concerned about safety and security at Chernobyl and Ukraine’s other nuclear facilities.”

Contintued concern over worker fatigue at Chernobyl

Earlier, SNRIU informed the IAEA that staff at the Chernobyl NPP were no longer carrying out repair and maintenance of safety-related equipment, in part due to their physical and psychological fatigue after working non-stop for nearly three weeks.

The staff of 211 technical personnel and guards have still not been able to rotate from the facility since the day before Russian forces entered the site on 24 February, the regulatory authority said, also voicing security concerns about transporting staff outside the Exclusion Zone set up after the accident.

SNRIU has no direct communication with the staff but receives information from off-site management. 

SNRIU also informed the IAEA that it was closely monitoring the situation in the Chernobyl NPP Exclusion Zone ahead of the annual “fire season” when spontaneous fires often occur in the area, still contaminated by radioactive material from the accident.

Grossi said the increasingly dire situation facing personnel at the facility – coupled with persistent issues related to communication from the site as well as the now resolved power supply problem – added further urgency to an IAEA initiative aimed at ensuring safety and security at Ukraine’s NPPs.

IAEA proposes framework to provide technical assistance to Ukraine's nuclear sites

Grossi has proposed a framework that would enable the IAEA to deliver technical and other assistance for the safe and secure operation of all of Ukraine’s nuclear facilities, which he had discussed with the Ukrainian and Russian Foreign Ministers Dmytro Kuleba and Sergei Lavrov, respectively.

“We can’t afford to lose more time. The IAEA stands ready to act immediately, based on our proposed framework that requires agreement from the parties of the conflict before it can be implemented. We can only provide assistance to Ukraine’s nuclear sites once it has been signed. I’m doing everything I can to make this happen very soon,” he said.

The IAEA is preparing detailed technical proposals for its assistance, based on its seven indispensable pillars for nuclear safety outlined at a meeting of the IAEA Board of Governors earlier in March. Those pillars – including the ones on the physical integrity of nuclear facilities, operating staff being able to make decisions free of undue pressure, secure off-site power supplies, and reliable communications with the regulator – have been compromised or challenged during the conflict.

SNRIU told IAEA it could no longer provide independent on-site regulatory safety oversight of the Zaporozhye NPP, in part because its working premises there had been damaged on 4 March. But it remained in constant contact with the site. On the status of Ukraine’s operational nuclear plants, the regulator said eight of 15 reactors remained operating, including two at the Zaporozhye, three at Rovno, one at Khmelnitsky, and two at South Ukraine. Radiation levels remain normal and safety systems were intact, it added.

In relation to safeguards, IAEA said it was still not receiving remote data transmission from its monitoring systems installed at the Chernobyl NPP, but that data was being transferred to IAEA headquarters from the other nuclear power plants in Ukraine.

Zaporozhye receives fuel deliveries; Russian personnel confirmed on site 

Regarding the Zaporozhye NPP, controlled by Russian forces since 4 March, the regulator said the power supply situation had not changed. It has four high voltage (750 kV) offsite power lines plus an additional one on standby. Two have been damaged. The operator has informed the IAEA that the NPP off-site power needs could be provided with one power line available. Diesel generators were also ready to provide back-up power and additional fuel deliveries arrived on 11 March. 

Ukraine has previously informed the IAEA that regular staff have continued to operate the Zaporozhye NPP and carry out their day-to-day work, but that its management is under the control of the commander of the Russian forces there.

SNRIU said it had been informed by personnel at the site that at least 11 representatives of the Russian state company Rosatom were present there, without interfering with the operation of the nuclear facilities. In his telephone call with Grossi, Likhachev confirmed that a limited number of the company’s experts were present at the site.  

In a separate statement, Rosatom also confirmed the dispatch of Russian specialists, but said the operation of Zaporozhe, like Russian-occupied Chernobyl, would be undertaken by Ukrainian staff. The Russian specialists would be there to "advise" the Ukrainian teams, the statement added.

Advice would be given on "the restoration of power at the Chernobyl facility and the physical protection system at the Zaporozhye power station", Rosatom said. "Operations to guarantee the safety of operations at Ukrainian nuclear facilities would be undertaken in contact with the IAEA." The interaction between Russian and Ukrainian specialists takes place on a regular basis in the format of meetings,” Rosatom noted. 

EBRD expresses concern over developments at Chernobyl

Meanwhile, on 11 March, the European Bank for Reconstruction and Development (EBRD) said it was extremely concerned by developments at the Chernobyl NPP. “[The] Bank has managed €2.5 billion in international funds to transform the site since 1995. The war must not be allowed to ruin recent achievements,” it noted. EBRD said its position on Chernobyl was “fully aligned” with IAEA and is based on the following safety and security considerations: 

  • Uninterrupted power supply must be maintained for the Chernobyl facilities. Any loss of power is potentially a serious threat to their nuclear safety. 
  • Since monitoring and control systems on site do not work, operators will not be aware of possible risks. They must stay in operation.
  • The Chernobyl facilities have been operated by the same depleted shift of employees for more than two weeks. Normal shift rotation as well as supplies to operating staff must be ensured.
  • Any military action on site is extremely dangerous for the old used fuel storage facility housing around 20000 RBMK fuel assemblies. 
  • Inspections by the Ukrainian regulator and the IAEA must be allowed.

WANO stands behind IAEA 

The World Association of Nuclear Operators (WANO) also said in a statement, 10 March, "that there can be no interference of any kind with Ukrainian member operators' ability to safely perform their work."

WANO’s performance objectives and criteria and safety principles provide high standards to guide nuclear plant operators worldwide on safe nuclear facility operation. WANO is concerned about factors in the current situation that may challenge these high standards of operation, including:

  • Staff not readily being rested, and under great stress, could jeopardize fitness for duty
  • Difficulties in providing supplies to stations 
  • Risk of inadequate supply of electricity for stations due to loss of offsite power
  • Fuel supply for long-term operation of emergency diesel generators
  • Possible external pressure that could jeopardize conservative decision making and the principle of safety being the highest priority
  • Weakened or disrupted communication lines with the regulator and support organisations such as IAEA and WANO

WANO has extensive data on nuclear power plant operations, and a well-established network for the sharing of operating experience and coordinating support among the world’s nuclear operators. 

They must continue to be ready access by Ukraine plant operators to these resources, and the availability of support from the global nuclear industry if needed.