New post on U.S. NRC Blog
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Baffle Bolts: An Updateby Moderator |
Neil Sheehan
Public Affairs Officer
Region I
Public Affairs Officer
Region I
There have been some new developments since our last blog post, on June 1,
regarding degraded reactor vessel bolts identified at a pair of nuclear
power plants in the Northeast. Most notably, both the Indian Point 2
plant, in New York, and the Salem 1 plant, in New Jersey, returned to
service over the summer.
Indian
Point 2 came back online in late June after 278 of the plant’s 832
baffle-former bolts were replaced. As for Salem 1, it was restarted on July 30th after changing out 189 of its 832 baffle-former bolts.
In
both cases, prior to the restarts, the NRC conducted independent
evaluations of analyses done for the plants’ respective owners by the
reactor vendors looking at how many new, more robust bolts had to be
installed to maintain safety margins and ensure the structural integrity
of the baffle-former plates. The agency also had specialist inspectors
at the plants for first-hand observations and information-gathering on
bolt-removal and -replacement activities.
Based
on those reviews, the NRC concluded that the reactors were safe to
operate. The bolts will be subject to further inspections at the
reactors’ next refueling outages, which typically occur about once every
18 to 24 months.
Nevertheless,
the NRC identified a “green” (very low safety significance) non-cited
violation at Indian Point 3 related to the bolts issue in an inspection report issued on Aug. 30th. A similar non-cited violation has also been identified at the Salem nuclear power plant, as documented in an NRC inspection report issued on Sept. 22.
In
both cases, the plant owners had not completed a necessary process to
document its conclusion, following identification of degraded bolts on
one unit, that the second unit was safe to continue to operate. After
the NRC raised concerns regarding the deficiencies, the companies
undertook corrective actions, including completing and documenting the
evaluations.
Looking
ahead, there is still more work to be done. Bolts from both reactors
have been or will be sent to labs for metallurgical analysis. Also, the
NRC will continue to engage the nuclear industry on its plans for
addressing the issue
An NRC web page has been updated to reflect the latest available information on this topic, including the NRC slides from a related July meeting and a summary of the session.
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Pollution controls have been made and installed for over 40 years. They typically remove at least 98%, and often 99.5% and more of the pollution that would have been emitted. Some emit so little that it is, at least at times, difficult to measure the emissions. They are enormously useful, successful, and valued.
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