Ukraine Crisis

Inside Zaporizhzhia: a timeline of events since Russia’s invasion

Nuclear safety is among the many casualties of war, and operators could not be more afraid. Matt Farmer investigates.


t the front of the invasion of Ukraine, soldiers discard nuclear safety like any other rule set aside in an unrestrained war. In an often-contested area, Ukrainian nuclear technicians scream to the wider world, hoping for some relief from the constant fear of disaster.

They claim that Russian troops have broken nearly every safeguarding tenet, from fire safety protocols to the very basics of not shelling nuclear reactors. Generating nuclear power in the heart of a conventional war “is unprecedented,” International Atomic Energy Agency (IAEA) director Manuel Grossi told CNN, “These are completely uncharted waters.”

Although the world is now watching, danger remains. As the expectations of war clash with the rules of nuclear safety, precedent is being written. What will the world learn from Zaporizhzhia?

The situation so far

Russia launched it full-scale invasion of Ukraine on 24 February. Quickly, the Zaporizhzhia plant (also transliterated as Zaporizya or Zaporizhzhya) found itself at the front of the war. Russian forces prioritised their push toward the plant, aiming to take control of power supplies and prevent Ukraine from selling power to Europe. The army captured areas close to the plant within one week. Early on 4 March, a fire broke out at the plant, causing immediate concern despite the lateness of the hour. Ukraine’s presidential advisor Mykhailo Podolyak summarised Ukraine’s reaction on Twitter: “Zaporizhzhia NPP is under fire! The entire[ty of] Europe is at risk of a repeat of the nuclear catastrophe. Russians must stop fire!”

As news spread, statements from countries allied to Ukraine immediately denounced fighting near the plant. However, Russian officials remained mostly silent on the issue.

"Immediately, comparisons were drawn with the notorious nuclear meltdown at Chernobyl, despite the many differences between the situations."

Immediately, comparisons were drawn with the notorious nuclear meltdown at Chernobyl, despite the many differences between the situations. Zaporizhzhia uses a safer, more modern design, incorporating learnings from Chernobyl. The plant also uses more rigorous procedures than Chernobyl, while having better communications and greater accountability. And while its reactors are built to withstand the impact of a moderately-sized plane, a direct strike from artillery would overwhelm almost any design.

The fire was soon brought under control. It then emerged that the blaze had started within administrative buildings at the plant, posing little direct risk to the reactors. Still, a live video feed giving unclear images of affected area did not help calm nerves around the radiation risk.

Both sides blame the other for shelling the plant. Given the reported inaccuracy of missile strikes by Russia, it is entirely possible that neither side intentionally shelled the plant. Regardless, neither Ukraine nor Russia accepts responsibility, tacitly acknowledging the impact that disregarding nuclear safety would have on international relations.

The IAEA’s involvement

After the fire, Grossi told CNN that the plant had not released radioactive material, but that it had seemed like a “close call”. He continued: “I’m telling [Russia] and everyone that the utmost restraint is to be exercised around this type of facility. Because wittingly or unwittingly, you can very quickly go into a disaster, and this is why we’re so concerned.”

The IAEA has almost universal international recognition for overseeing safety measures around atomic energy and radioactive substances. In an average year, they would review nuclear safety regulations across the world, inspect decommissioning efforts at nuclear plants, and respond to a variety of incidents.

The IAEA’s work emphasises seven “indispensable” pillars of nuclear safety. These are: physical integrity of nuclear facilities, functionality of safety equipment, ability of operating staff to act “free of undue pressure”, an off-site power supply, uninterrupted supply and transport chains, effective and widespread radiation monitoring with readiness in case of emergency and reliable communications.

This year, the violation of these pillars by military units at Zaporizhzhia has dominated the agency’s concerns. The fire marked the first of several incidents threatening the structural integrity of systems at the plant. Frequently throughout the year, fighting has disrupted communications with the plant, violating another key pillar of safety.

Following the fire, his organisation issued a statement “deploring the Russian Federation’s actions in Ukraine”. The IAEA also “expressed grave concern that Russia’s aggression impedes the agency from fully and safely conducting safeguard verification activities.”

He also requested that the IAEA could be allowed to access the plant and report on its status freely. Continuing fighting in the area made guaranteeing the safety of this mission difficult, and negotiations for the mission began on 6 June.

Russian invasion of Ukraine enters nuclear plant

From the start of their occupation of the Zaporizhzhia plant, Russian forces have clashed with staff of Energoatom, Ukraine’s state-owned nuclear company. Via online statements, the company has repeatedly accused Russian forces of interfering with operations at the plant, although few of these incidents have been independently verified.

On 29 June, a statement from the company accused Russian forces of conspiring to frame Ukrainian operators as irresponsible. It reads: “The invaders are going to accuse the Ukrainian nuclear workers of storing weapons at the power plant site.

"The invaders are going to accuse the Ukrainian nuclear workers of storing weapons at the power plant site."

“To do this, several workers were detained and tortured to force them to incriminate themselves; to say that in March they allegedly dropped explosives or shells into the concrete basins of cooling ponds at the plant.”

Energoatom said that Russian forces may then leave weapons in the cooling ponds themselves, aiming to discredit Ukrainian operating staff. This would then become propaganda, or “evidence” presented to the IAEA to demonstrate supposed irresponsibility from the plant’s staff. The next day, 30 June, Energoatom announced that Russian troops had forced its staff to drain the cooling ponds. This then restricted coolant flows to the reactors, violating another pillar of nuclear safety.

Affecting nuclear generation

Aside from safety risks, nuclear plays an essential role in the Ukrainian economy. According to the International Energy Agency, nuclear power has provided the largest share of Ukraine’s energy generation since at least 2000. As a result, authorities remain enthusiastic to keep nuclear plants generating and kept two reactors running after the outbreak of war.

Furthermore, since Ukraine synchronised with the European ENTSO-E grid, international power sales have become an important source of income for Ukraine’s power companies. In the long term, Ukrainian generators hope to sell power to the EU to assist the country’s economic recovery.

Zaporizhzhia is Europe’s largest nuclear plant, and one of four operating within Ukraine. At one point, it supplied 20% of all Ukraine’s electricity. The plant as six nuclear reactors, but for most of the war, only two have remained in operation.

On 5 August, the shelling of the plant’s electrical switchboard and nitrogen-oxygen station caused it to briefly disconnect from the grid. This would be the first of several similar incidents, where shells damaged equipment on 6, 11, and 25 August.

These shell strikes often hit power lines connecting the plant to the grid, which soon became central to safety concerns. Ideally, the plant would have four connections to the external grid, ready to power its internal safety functions if needed. However, Russian forces have attempted to separate the grids of occupied territories from those of Ukraine, with Zaporizhzhia lying close to the dividing line.

“The staff are now hostages”

Energoatom’s Petro Kotin has said that Russian forces planned to separate Zaporizhzhia from the Ukrainian grid and use its power for Russian-held areas. Workers at the plant have said that this would take “two to three months” to organise. Whether or not this is true, in the weeks running up to September, power lines connecting Zaporizhzhia to the grid began to take more damage from shells, slowly eliminating the plant’s redundancies.

Also, during August, satellite images first showed Russian military vehicles and equipment in and around the plant itself. On 24 August, Ukrainian authorities had told the IAEA that “more than 40” units of military equipment lay within the plant. Energoatom representatives have said that the Russian army has stored significant amounts of explosives within the turbine halls of Zaporizhzhia’s active reactors.

"Energoatom representatives have said that the Russian army has stored significant amounts of explosives within the turbine halls of Zaporizhzhia’s active reactors."

Workers told the BBC that forces had threatened to shoot them for leaving the plant. One worker said: “Access to all roofs is prohibited; they made their observation points there. The training building also became their barracks. Now, more and more often, staff are kidnapped just when leaving the shift at the security gate.

“The staff are now hostages of the Russians. They turned off the internet, left only landline phones, and food is available only in one single dining room. They turned the others into their bases.” 

Loss of grid connection

In late August, an IAEA team was able to reach the site for the first time. In Moscow, Russian foreign minister Sergei Lavrov addressed the inspectors, saying that Russia was “doing everything to endure that the power station is safe, and is functioning safely”. He also said Russian forces aimed to enable the IAEA to complete its assessment.

This was not reflected by social media posts from around this time, reported by Ukrainian media as coming from Russian troops. Quickly-deleted Telegram posts by Russian forces threatened the integrity of the plant, telling the world: “The plant will either be Russia’s or nobody’s”.

On 1 September Energoatom announced that following nearby shelling, it had shut down another reactor, leaving only Unit 6 running. On 5 September, more shelling caused a fire that damaged the plant’s power connection to the Ferosplavna power plant. Engineers then disconnected this, the last power connection to the outside world. This led Energoatom to put Unit 6 in “island mode”, where it powered only the functions of the plant itself.

On 11 September, Zaporizhzhia shut down its last reactor. However, the plant still requires power to maintain safety, keep cooling pumps running, and communicate with authorities. This is why engineers restored operations to a power line on 17 September, allowing critical functions to continue. 

Looking forward

After weeks of negotiation, an IAEA observer team arrived at Zaporizhzhia nuclear plant on 1 September. On 6 September, the IAEA released its first report using evidence gathered from the site. The main body of this 52-page report confirms and clarifies events that have transpired so far, suggests steps to remedy them, and emphasises the seriousness of the situation.

Its conclusions read: “The IAEA is still gravely concerned about the situation at the ZNPP – this hasn’t changed. The seven pillars have all been compromised at the site. Therefore, the IAEA has made recommendations against each of the seven pillars.

“The staff at all of Ukraine’s nuclear facilities have continued to show endurance and resilience in keeping the sites running in a safe and secure way amid the conflict, and the IAEA salutes them.”

Both sides of the conflict contest aspects of the report. An Energoatom statement accused Russian forces of lying to the mission, while Russia’s Lavrov said the report contained “a number of issues” which would require “additional explanations”.

"An Energoatom statement accused Russian forces of lying to the mission, while Russia’s Lavrov said the report contained ‘a number of issues.’"

Following this publication, the agency issued a plea to establish a “nuclear safety and security protection zone” around the plant. It has now taken these requests to the UN, hoping to demilitarise Zaporizhzhia. The delegation plans to remain at the plant for as long as possible, which it says “will be of paramount importance in helping to stabilise the situation”.

Updates from the IAEA emphasise that the situation “remains precarious and that immediate action is needed to reduce the risk of a major accident”. At time of writing, the plant lies within Russian-controlled territory, although Ukrainian counter-offensives could eventually see the site change hands.

Energoatom said that the plant had been shut down on 11 September, but with Russia still in control of the facility and Ukrainian workers still at the plant, the future remains unclear.

Threats to the plant’s integrity remain constant, immediate, and unforeseeable. Ukraine alleges that Russian forces intend to keep disconnecting the plant from its power grid, and have claimed that Russian forces will soon withdraw from the facility, which Russian officials have denied.

The presence of the IAEA has helped to give transparency to the situation, even if the organisation remains deeply anxious over the situation at Zaporizhzhia. The fact remains that only one stray missile in the wrong place could result in unthinkable destruction.

// Main image: Zaporizhzhia nuclear plant. Credit: Ihor Bondarenko via Shutterstock