Nuclear Time Bombs

Few environmental nightmares strike a more frightening chord than Chernobyl. It is not merely the radioactive mess left by the 1986 meltdown. Six years later, 19 similar graphite-moderated nuclear time bombs are still ticking away, alarming relics of a badly designed, haplessly run nuclear-power program that none of the independent republics of the former Soviet Union can afford to shut down. The potential killers bring light, heat and power to parts of Russia, Ukraine and Lithuania, where their immediate decommissioning would create unacceptable economic disruption and even civil unrest.

The handling of Chernobyl is hardly reassuring. When workers finished the huge steel-and-concrete shell that entombs the intensely radioactive mass of the shattered No. 4 reactor in late 1986, Soviet officials declared the site safe for at least 30 years. Yet today the sarcophagus is cracked, crumbling and in peril of a disastrous collapse. The melted-down fuel is turning to unstable dust. Contaminated objects are being smuggled out of the poorly guarded 1,092-sq.-mi. exclusion zone. Birds fly into the sarcophagus through holes as big as a garage door; rats breed in the ruin. The structure is so unsteady that a strong windstorm could smash it, sending a plume of radioactive dust into the atmosphere. "Nothing is being done to clean it up," says Alex Sich, an American engineer who has studied the Chernobyl site.

Nor has anything been done about the threat of nuclear contamination in the oceans. Over the years four Soviet submarines, their reactors full of nuclear fuel, sank accidentally. The most dangerous, the world was reminded last week, may be the Komsomolets, which caught fire in April 1989 and went down in more than 4,500 ft. of water 310 miles off the coast of Norway. The wreck is already leaking cesium-137, a carcinogenic isotope. So far the leakage is considered too small to affect marine life or human health.

But the Komsomolets also carried two nuclear torpedoes containing 28 lbs. of plutonium with a half-life of 24,000 years and toxicity so high that a speck can kill. Russian experts warned that the plutonium could spill into the water and contaminate vast reaches of ocean as early as 1994.

At Chernobyl the concern is even more immediate. There is ever-present danger in the operation of reactor No. 3 too. Despite a government plan to shut down the entire plant, No. 3 was reactivated after officials pleaded that its energy was essential for the coming winter. Like its ruined twin, No. 3 is ; considered fundamentally unsafe by the International Atomic Energy Agency. It may be even more so now: many Russian operators have returned home, leaving a reactor run by Ukrainians who are ill-trained, badly paid and demoralized.