Operators Damage Key Arms Reactor

WASHINGTON — Operators at the Savannah River Plant in South Carolina mishandled a routine pressure test last weekend and damaged pipes and valves on a critical nuclear-weapons reactor that the Energy Department had hoped to restart this year.

Officials said the accident Sunday damaged a backup cooling system for the K Reactor, one of three Savannah River reactors that have been shut down for safety reasons since April. The reactors are the nation’s only source of tritium, a perishable component of nuclear weapons. And the K Reactor was expected to be restarted first.

Energy Department officials said the accident posed no health or safety problem and that it is too early to know whether the damage will delay the restart of the reactor.

But the accident raised new questions about operating procedures at the aging weapons complex, and the department said it has halted testing and maintenance work there until after the incident has been investigated.