Experiments at Chernobyl Under Way at Time of Blast

A Soviet nuclear safety official said Wednesday that experiments were being conducted on the Chernobyl reactor when the explosion and fire occurred April 26, but he would not say whether they were related to the disaster.

Viktor A. Sidorenko also told reporters that Moscow was notified of the trouble in less than three hours. The Kremlin did not acknowledge the accident until nearly three days later, after high levels of radiation had been detected in Scandinavia and Sweden demanded an explanation.

The 92,000 people evacuated from within a 19-mile radius of the Ukrainian power plant apparently will not return until at least next year. The Communist Party newspaper Pravda said Wednesday that 10,000 homes and many barns will be built for evacuees and their livestock and that thousands have been sent to new jobs.

Each person evacuated will receive compensation of 200 rubles, the equivalent of $283, Pravda said.

It complained that hundreds of evacuated mothers with small children have not yet been sent to summer camps because of bureaucratic indifference, and that many families still are separated.

Mothers with preschool children and the youngest school pupils were to have been sent to camps and rest homes at such resort areas as the Black Sea.

In Vienna, governors of the International Atomic Energy Agency from 35 countries, including the Soviet Union, agreed to work toward binding accords on notification of nuclear disasters and emergency assistance.

Talks at the U.N. agency, called in response to the disaster at Chernobyl, ran late into the night, but delegates from the East and West expressed satisfaction with cooperation at the emergency board meeting.

In Moscow, no new official casualty figures were issued. The unofficial death toll is 13, two in the reactor accident at the power plant 60 miles north of Kiev and 11 of radiation poisoning.

Sidorenko, deputy chairman of the State Committee for Nuclear Inspection, met with a few Western journalists in one of several interviews with government experts that have been arranged in the past two weeks.

He repeated earlier official statements that the reactor’s heat output had been lowered to 6% or 7% of capacity for “planned annual repairs.”

“We planned to hold some experiments, research work, when the reactor was on this level,” he said. “The accident took place in the stage of experimental work.”

The safety official would not describe the experiments or reveal what relation they might have to the accident, saying only that they were “connected with the checking up of some of the systems of the station.”