The Chernobyl radioactive cloud was first detected over northeastern Poland at a monitoring station in the lakeside resort of Mikołajki, state news agency PAP reported.
The alarm was raised on April 28, 1986, two days after reactor No. 4 exploded at the Chernobyl nuclear power plant.
The discovery was made in Mikołajki, a town in Poland’s Masurian lake district, by employees of the Institute of Meteorology and Water Management (IMGW).
Stanisław Leszczyński, who headed the local IMGW station, said years later that the staff immediately informed the institute’s headquarters in Warsaw and the Central Laboratory for Radiological Protection.
Polish communist-era authorities, however, did not inform the public about the contamination for many hours. The Soviet authorities imposed an information blockade after the April 26, 1986 explosion.
Polish historians say the delay reflected both Soviet secrecy and the habits of communist rule. Moscow initially imposed an information blockade and did not give Warsaw reliable details about the disaster, while Poland’s communist authorities, operating under censorship and political dependence on the Soviet Union, limited themselves at first to brief reassurances.
Many Poles learned more from Western radio stations than from state media, even as Polish experts were already pushing the authorities to begin the mass distribution of Lugol's iodine solution to protect children’s thyroid glands.
“Until 8 p.m. on Monday, April 28, 1986, I did not know what the cause of the radioactive radiation was,” Leszczyński recalled in a video interview recorded years later by a local internet television channel in Mikołajki.
“There was no information on the radio, on any waveband. I suspected that a plane had lost an atomic bomb, or that there had been an explosion at a power plant.”
He said Warsaw radio first reported a leak from a reactor in Sweden. Leszczyński realized that explanation did not fit the weather pattern because air masses over Poland were then coming from the southeast.
Later reports said a radioactive cloud was moving over Poland and Europe.
At one point, Leszczyński said, he considered asking the local parish priest to ring the church bells to summon residents. The idea was abandoned. It was a warm, sunny day, and people were working in gardens and on allotments, but station staff did not warn them directly.
“It was a confidential matter. The measurement results were confidential,” Leszczyński said years later.
The Mikołajki station had been carrying out routine atmospheric contamination checks since 1958, at a time when nuclear powers, including the United States and the Soviet Union, were conducting weapons tests.
Similar monitoring stations operated elsewhere in Poland.
The discovery in Mikołajki soon drew international attention. Leszczyński recalled that journalists from around the world arrived in the town after authorities acknowledged that contamination over Poland had been detected there.
He said one Italian reporter falsely claimed that residents had been evacuated and illustrated the story with a photograph of the empty town square taken at dawn.
"On our side, we did not sleep through this situation. The Polish government learned about the contamination from a Polish service," Leszczyński said.
The Chernobyl disaster remains the worst accident in the history of nuclear power. The explosion on April 26, 1986, killed dozens of people in the immediate response period and forced the evacuation and resettlement of hundreds of thousands from contaminated areas of Ukraine, Belarus and Russia.
The long-term death toll remains disputed. Estimates vary widely, from several thousand to much higher figures, depending on methodology and the health effects counted.
(rt/gs)
Source: dzieje.pl, radioolsztyn.pl, polskieradio24.pl