Caption: Susquehanna nuclear power plant
PPL's (NYSE: PPL) Susquehanna nuclear power plant Unit 2 automatically shut down while power was being decreased for a scheduled maintenance outage.
On April 10 when the reactor was around 37 percent power, turbine steam seals were lost which resulted in a degraded vacuum, according to an event report filed with the U.S. Nuclear Regulatory Commission. The vacuum degraded quickly, causing a main turbine trip before the operator could insert a manual scram. All control rods fully inserted. The condenser vacuum has since been restored.
Once the reactor was shut down, workers found a leak in a weld on April 11. The leak was from a weld on the 3/4-inch seal vent piping connected to the 2A reactor recirculation pump seal area. The location is within the reactor recirculation loop isolation valves, so it is able to be isolated from the reactor vessel.
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