Idle Weapons Reactor Found to Be Free of Cracks; 2 Others to Be Tested

Engineers looking for cracks in the three idled reactors at the Savannah River nuclear weapons complex have given one of the units a clean bill of health, according to a report released Friday by the Energy Department.

Tests on the two other reactors are scheduled for early next year as part of the department’s effort to determine if the aging structures are sound enough to restart. They have been shut down for more than a year for safety reasons.

The possibility of cracking in the reactor vessels, which encase rods that fuel the atomic chain reaction, has been a central concern as the government undertakes a $1.66-billion program for repairing and modernizing the three reactors and retraining the thousands of contract workers who operate the facility near Aiken, S.C.

The Savannah River reactors are the nation’s only source of tritium, a radioactive gas used in nuclear warheads. Tritium decays at a rate of 5.5% a year, so supplies in warheads must be replenished or the bombs cease to function.

Barring any unforeseen problems such as vessel cracking, Energy Secretary James D. Watkins hopes to restart the K reactor by next fall; the second, L reactor, by December, 1990, and the third, P reactor, in spring, 1991.

In Friday’s report on results of ultrasonic testing at P reactor, Westinghouse Savannah River Co., which runs the plant under an Energy Department contract, said there were no signs of cracking.