The UN's nuclear watchdog chief is in Ukraine. Here's what we know

begin partial quote from:

https://www.cnn.com/europe/live-news/ukraine-russia-putin-news-03-30-22/h_992fc89a0be076206f1f151fbf26280e 

The UN's nuclear watchdog chief is in Ukraine. Here's what we know

Rafael Mariano Grossi, director general of the International Atomic Energy Agency (IAEA), is in Ukraine for urgent talks with the Ukrainian government about the safety of the country's nuclear facilities. 

Here's what we know:

Grossi posted a photo of himself on Twitter standing in front of an official UN vehicle on Tuesday, saying he had "just crossed the border into Ukraine to start the IAEA's mission to ensure the safety and security of the country's nuclear facilities." 

• In a statement, the IAEA said Grossi is in Ukraine to "initiate prompt safety and security support to Ukraine’s nuclear facilities."
• Talks with senior government officials will center on the agency's plans to deliver "urgent technical assistance" and "help avert the risk of an accident that could endanger people and the environment," the statement said. 
• Grossi's location in Ukraine has not been disclosed.

Some context:

• Russian forces have occupied Ukraine's largest nuclear power plant, Zaporizhzhia, since March 4, and the Chernobyl nuclear power plant — site of the infamous 1986 accident — since Feb. 24. 

Safety fears:

• There are concerns over the safety of the nuclear sites, reactors and staff at the facilities.
• Grossi said the conflict is "putting Ukraine’s nuclear power plants and other facilities with radioactive material in unprecedented danger."  

Preventing a nuclear accident:

• Grossi warned "there have already been several close calls" at Ukraine's nuclear facilities since Russia's invasion began.
• He is set to visit one of the country's power plants during his trip.
• His visit comes after Ukraine "requested our assistance for safety and security," Grossi said.

"We can’t afford to lose any more time," he said, adding that the IAEA's expertise is needed urgently to prevent any nuclear accident.

Nuclear sites in Ukraine:

• The country has 15 nuclear power reactors at four plants, as well as the Chernobyl plant.
• The IAEA said eight reactors continue to operate, including two at the Russian-controlled Zaporizhzhia plant, three at Rivne, one at Khmelnitsky, and two at the South Ukraine facility. The other reactors remain closed for regular maintenance.
• The watchdog said it has drawn up "concrete and detailed plans for safety and security assistance."

Several scares:

• On March 23, the Ukrainian government said Russian forces looted and destroyed a lab close to the Chernobyl nuclear power plant, which was used to monitor radioactive waste. The government agency also reported that samples of radionuclides — unstable atoms that can emit high levels of radiation — had been removed from the lab.
• Staff working at Chernobyl on the day it was captured only recently had the chance to go home, three weeks after they were due to rotate with an incoming team. Workers had been confined to the plant for 10 days and were “exhausted, both mentally and emotionally, but mainly physically," the local mayor said.
• Earlier this month, the site was forced to use power from emergency diesel generators for several days, before being reconnected to the national electricity grid after repairs to damaged lines.
• Ukraine’s government also warned of several fires close to the plant, which it said had probably been triggered by Russian artillery or arson.