A May 10 reactor trip at the Pilgrim
nuclear plant resulted in a special inspection from the Nuclear
Regulatory Commission, the agency announced Monday.
According to an NRC release, operators
at the Plymouth, Mass., plant were bringing the reactor back online
after a refueling outage when the incident occurred. Entergy
employees were bringing the boiling water reactor up to full power
when they noticed a higher-than-anticipated heat-up rate of the core
while withdrawing the control rods. Operators tried to reduce the
heat-up rate, according to the NRC, but their actions and the
reactor's response caused the reactor's safety systems to shut down
the reactor automatically.
“There were no immediate safety
implications associated with the unplanned shutdown,” NRC Region I
Administrator Bill Dean said in the release. “Nevertheless, we want to gain a
better understanding of exactly why the shutdown occurred, what role
human performance issues may have played in the event and the steps
being taken by the company to learn from this event and prevent it
from happening again in the future.”
On Monday a three-person inspection
team from the NRC began evaluating the operator's performance and
decision making.