The RBMK-1000 Reactor

The Chernobyl reactor complex just 80 miles north of Kiev, Ukraine is made up of four Russian made RBMK-1000 water-cooled graphite moderated reactor designed to make plutonium for nuclear weapons and modified to also produce electricity. There are 27 RBMK's in the former Soviet Union. One distinguishing feature of the RBMK design is its use of graphite to slow the neutrons produced by the fissioning of uranium-235 atoms. Besides the RBMK reactors, the U.S. Department of Energy operated a graphite-moderated reactor at Hanford, Washington for the dual purpose of producing military plutonium and electricity up until the aftermath of the Chernobyl accident. Within the reactor core of a RBMK, nuclear fuel is placed in long separate vertical channels surrounded by graphite, which is expected to absorb large amounts of heat as a safety feature to give reactor operators ample time to take corrective action in the event of an accident.

While significant differences in both design and construction exist between the Chernobyl-style reactor and U.S. commercial power reactors, the nuclear accident stands as an indictment of nuclear power technology and the catastrophic consequences inherent in the fissioning of the uranium atom to generate steam for electricity.

The Ongoing Consequences of the Nuclear Accident

At 1:23 a.m. on April 26, 1986, a catastrophic nuclear accident demolished Chernobyl Unit 4. Power plant operators lost control of the reactor while conducting experiments at low power. In an enormous explosion of the reactor core, a mammoth amount of heat and disintegrated radioactive fuel violently erupted into the atmosphere. An atomic fire burned for days before Swedish authorities alerted the world to the return of nuclear fallout spewed high into the atmosphere. Only months early, Soviet Life had propagandized that operating the Chernobyl nuclear power plants was "safer than driving a car."

The facts are still coming forward:

There is roughly a 36 mile diameter "dead zone" surrounding the reactors from which over 160,000 people were evacuated, permanently abandoning over 600 years of continuous habitation and culture around the towns of Chernobyl and Pripyat. Numerous "hot spots" of radioactive contamination persist far beyond a "zone of alienation;" many areas continue to emit radioactivity at levels ranging from 40 to 100 curies/kilometer2. As many as 150,000 people were dislocated in Belarus and 75,000 in the Russian Federation.

It is estimated that nearly 80% of Belarus was hit by iodine-131 fallout at 1000 curies/kilometer2, but because this isotope is short-lived (80 day hazardous-life) it was omitted from the long-term forecasts and analysis despite its extremely significant health consequences.

Vast tracks of agricultural land and bodies of water have been poisoned in Ukraine, Belarus, western Russia, with significant radioactive contamination persisting as far away as Poland, Norway and Sweden .

In an effort to avert a second nuclear catastrophe at the site, the international atomic industry puzzles over its next move to prevent or contain the eventual collapse of the colossal concrete tomb hastily erected at great human sacrifice as a biological barrier. The concrete pillars supporting the "sarcophagus" are crumbling and ready to burst over the highly radioactive remains of the damaged reactor, which would result in another catastrophic airborne release of radioactive particulate to the environment.

Wind and water continue to spread Chernobyl's deadly radioactive contamination over even wider areas. Ground water flowing under the damaged Chernobyl reactor is spreading an underground radioactive plume into the Pripyat and Dnieper Rivers, threatening the city of Kiev's water supply.

Now, nearly ten years later, the Ukrainian government estimates 8000 people have died in their country from the nuclear accident as a result of radiation-related illness. The Ukrainian Ministry of Health places that figure at 125,000 with disease rates, miscarriages and birth defects steadily rising. Officials in Belarus estimate that roughly 2 million have suffered in some way as a result of the nuclear meltdown. Birth rates have fallen 50% in Belarus. Over 3 million Russians were exposed to the radioactive fallout in 1986. An estimated 370,000 Russians are believed at significant risk for radiation illness according to a recent Moscow medical conference. The relocation of hundreds of thousands of people from additional contaminated zones has ground to a halt for economic reasons, as has radiation monitoring of farming produce in the zones.

According to United Nation sources, Belarus currently spends 20% of its national budget dealing with the Chernobyl aftermath while Ukraine devotes 4% of its budget. In a report prepared by the Minister for Extraordinary Situations and Protection of the Population from the Consequences of the Chernobyl Catastrophe, the estimated total cost to Belarus from 1986 to 2016 is the equivalent of 32 annual budgets from the republic's pre-accident period.

Chernobyl's Implications For U.S. Nuclear Reactors

The U.S. nuclear power industry is quick to point out that the Chernobyl accident was a unique event that could never be repeated at a Westinghouse, General Electric, Babcock and Wilcox or Combustion Engineering design. The industry claims that Chernobyl was the product of a severely flawed reactor design that could never be licensed to operate in the United States. Industry proponents continue to claim that all U.S. nuclear reactors are designed to ensure that radioactive materials would be contained in the event of a serious accident. However, Chernobyl also had a containment building. The accident was so severe that the containment design failed. Considerable evidence indicates that U.S. containment designs can also fail. The U.S. Nuclear Regulatory Commission (NRC) in a 1990 study of the risks associated with severe accidents at U.S. nuclear power plants concluded that none of the five different designs it analyzed were capable of remaining intact during a severe accident. In another NRC study of 24 U.S. reactors using General Electric's Mark 1 containment design, NRC concluded that "failure within the first few hours following core melt would appear rather likely."

All aging U.S. nuclear reactors are vulnerable to component failure and human error in design, construction and operation. Any U.S. nuclear reactor could have an accident resulting in a catastrophic release of radiation to the American public with similar or worse consequences as evidenced by Chernobyl.

Prepared by Paul Gunter, December 5, 1995

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