Chernobyl: Anatomy of a Disaster

The problems at Chernobyl began long before 1986, as David Marples writes in the introduction to nuclear engineer Grigory Medvedev’s book on the Soviet nuclear industry, No Breathing Room: “Several scientists at the Kurchatov Institute of Atomic Energy expressed concern about the RBMK [the type of graphite-moderated reactor at Chernobyl] in the early 1970s. More than thirty design flaws were reportedly uncovered, but none was corrected before the reactor first went into service. At least one official was dismissed for trying to draw attention to these defects.”

Remarkably, as Marples also reports, just prior to the Chernobyl disaster, in the spring of 1986, journalist Lyubov Kovalevska penned an article for the weekly paper of the Ukrainian Writers Union, Literaturna Ukraina, in which she pointed out flaws in the plant’s construction and called the station “an accident waiting to happen.”

The accident occurred on April 26, 1986, during an otherwise quiet weekend. Unqualified technicians were conducting a bizarre and unnecessary experiment that, had they know the reactor’s built-in flaws (it does not operate safely at low power), they would not have ventured. When the experiment spun out of control through a series of incompetent decisions, every attempt to control the nuclear reaction worsened the situation, until the engineers desperately tried to reinsert the fuel rods in a last ditch bid to slow the reaction. This was the final fatal error, because the rods were constructed in a way that ended up accelerating the reaction and leading to a massive explosion.

Medvedev described the scene: “Flames, sparks, and chunks of burning material went flying into the air above the Number 4 unit. These were red-hot pieces of nuclear fuel and graphite, some of which fell onto the roof of the turbine hall where they started fires...

About 50 tons of nuclear fuel evaporated and were released by the explosion into the atmosphere... In addition, about 70 tons were ejected sideways from the periphery of the core, mingling with a pile of structural debris, onto the roof...and also onto the grounds of the plant... Some 50 tons of nuclear fuel and 800 tons of reactor graphite... remained in the reactor vault, where it formed a pit reminiscent of a volcanic crater.”

The fallout was immense, particularly in the Gomel region of Belarus. In fact, Belarus bore the brunt of the fallout. The Chernobyl station lies just a dozen miles from the Ukraine-Belarus border.

Total casualty figures are still not known, but certainly more than 2,000 persons are thought to have died as an immediate result of the accident and its cleanup (much of it done by heroic “volunteers” without adequate protective gear). Many thousands were put at risk for cancer due to the fallout of radioactive iodine. And a region which once had 350,000 persons is now Europe’s largest (radioactive) wilderness area [see Under Review, page 61].

The other three reactors at Chernobyl continued to operate for some time before they were taken out of operation. The last reactor, number 3, was shut down on December 15, 2000.