Unit 2 at the Susquehanna nuclear power plant near Berwick returned to service Thursday night (8/1) after an 18-day outage to repair an electrical circuit breaker and complete an investigation of plant procedures related to backup diesel generators.

"On July 14, a loose connection caused a circuit breaker to fail to close. That led plant operators to shut down Unit 2 manually," said Herbert D. Woodeshick, special assistant to the president for Pennsylvania Power & Light Co., which operates the plant.

While the unit was shut down, an earlier incident in which switches for one of the plant's five backup diesel generators were misaligned was investigated. Personnel issues were addressed during the investigations of both situations.

Both now have been corrected, Woodeshick said. Susquehanna Unit 1 shut down automatically early Thursday morning (8/1) after sensors detected abnormal vibrations in the unit's turbine. It had been in service for 238 days, since an outage in November 1995 to repair its main generator.

The Susquehanna plant, located in Luzerne County about five miles north of Berwick, is owned jointly by PP&L and Allegheny Electric Cooperative Inc.