Reactor Blast Shows Danger Of Aging Subs
By David Hoffman
The chief officer decided not to report the matter and returned with his crew that Saturday to fix it. They lifted the lid of the reactor, weighing 12 tons, but did not detach a lattice, which held the control rods in place. It was five minutes before noon.
Just as the rods were inched out, a navy torpedo boat swept by, creating a big wake. The wake rocked the floating repair station. It jerked up the control rods -- and the reactor exploded.
A scarlet fireball, 20-feet high, shot straight up. The 12-ton lid was blown into the air and crashed back into the sub; a cover of the floating refueling station also was blown off, landing 100 feet away.
The fire took four hours to extinguish, and a radioactive plume floated across the Dunai Peninsula. Viktor Khramtsov, then a rear admiral and commander of the Pacific Fleet's 4th Flotilla, recalled recently that when he arrived on the scene "it was difficult to breathe there."
Ten sailors were killed instantly, including eight officers, and 290 people were overexposed to radiation. It was found later that reactor fuel had been blown out of the sub onto neighboring vessels, on the shore and in the water. More than a decade later, portions of the seabed are still severely contaminated, according to recent research by experts in the region.
The accident at Chazhma Bay shows what could go wrong today as Russia struggles with more than 100 decommissioned submarines in the Far North and Far East that still have reactors aboard and have not been defueled. These submarines could be the source of a radiation leak or explosion.
At Chazhma Bay, the submarine was not decommissioned, but rather was a working vessel. The reactor had been freshly loaded; had it been spent fuel, the radioactivity could have been much higher. Moreover, the explosion occurred on a Saturday, when the nearby yards were empty, and the winds blew the plume over a sparsely populated peninsula.
The explosion at Chazhma Bay came nine months before the Chernobyl nuclear power plant disaster. Like Chernobyl, the submarine explosion stemmed from human errors, which led to an explosion, fire and radioactive contamination. But unlike Chernobyl, which the Kremlin tried and failed to keep secret, the submarine catastrophe at Chazhma Bay was successfully hushed up for many years. Military commanders described the incident only as a "thermal explosion," not a nuclear one, and radioactive detritus was hastily buried in trenches.
Details about the accident only came to light in a 1993 report after the collapse of the Soviet Union -- and even then, there was resistance to releasing the full story, according to Alexei Yablokov, who was then President Boris Yeltsin's environmental adviser.
Khramtsov, the former naval commander, provided a vivid account of the aftermath in an interview this year with the newspaper Trud. He recalled that the initial reports were about a "thermal explosion" at Chazhma Bay. "At that moment, there was still hope that the worst hasn't happened," he said. "A thermal explosion is not a nuclear one, I kept telling myself."
But he was wrong. When he got to the site, just four hours after the blast, he recalled, the sub was sinking. The reactor compartment was filled with water. Khramtsov and a few other officers, using fire axes, severed the ropes and cables and the radioactive sub was towed to shallow water by the shore. They started the pumps -- and "the contaminated water was poured into the gulf."
Khramtsov described how an intensive cleanup was attempted over the next 13 days. The area around the sub was declared an emergency disaster zone. Three to five feet of contaminated topsoil was scraped off by bulldozers. Whole panels were stripped from "luminescent" buildings "and disposed of in the hills."
The radioactivity released from the accident was substantial. Donald J. Bradley, a specialist at the Pacific Northwest National Laboratory who recently published a book on radiation waste and contamination in the former Soviet Union, estimates that the Chernobyl accident released 50 to 80 million curies into the environment, with about 1.5 million remaining in 1996. (A curie is a unit of radioactivity in matter, equivalent to the number of disintegrations undergone by one gram of radium in one second.) The Chazhma Bay explosion released about 7 million curies, according to Bradley, with 150,000 remaining in 1996.
Yablokov chaired a special commission established by Yeltsin to prepare a report on the dumping of radioactive and chemical waste at sea, which turned up the long-hidden data about Chazhma Bay in 1993. The report revealed that the explosion had contaminated part of the bottom sediments of the bay with radioactive cobalt-60.
The contamination persists, according to new findings prepared this year for Green Cross Russia, an environmental group that has compiled a detailed new study on the radiation legacy of the Cold War, drawing on declassified Russian documents.
Eleven years after the accident, experts at the Radioecological Center of the Hydrosphere in Vladivostok, found that the concentration of radioactive cobalt in the bottom soils is 250-300 times the normal level. They concluded that heavily contaminated bottom soil from the accident site is being freshly exposed by erosion -- and continuing to keep the area highly contaminated.
© Copyright 1998 The Washington Post Company