Event Reports: A reactor trip in New Jersey, bad welds and an earthquake in Virginia and continued Fitness for Duty problem at nuke construction site in Georgia

Four items from today’s NRC Event Reports:

1. On Friday afternoon, the Unit 2 reactor at the Salem nuclear power plant in New Jersey experienced an automatic reactor trip. During the incident, two reactor coolant pumps were unavailable, due to a pair of electrical buses that failed to energize, causing an auxiliary feedwater system activation. The reactor was at 100 per cent output prior to the shutdown. The unit remains at 0 per cent output as of this morning’s Reactor Status Report.

2. Saturday evening, technicians at the North Anna nuclear power plant in Virginia discovered that two steam generator nozzle welds in the Unit 1 reactor had through-wall defects and were leaking coolant. The reactor is currently shut down for refueling.

3. Late Sunday night, the North Anna station declared an emergency for both units due to a 3.1 magnitude earthquake in the area. After an inspection, plant operators decided that no significant damage had taken place. Both reactors at North Anna had been knocked out on August 23, 2011, by a 5.8 magnitude earthquake, resulting in extended outages.

4. The NRC received an update on earlier reported problems with the Fitness for Duty program at the construction site for two new units at the Vogtle nuclear power plant in Georgia. On March 9, contractor Shaw Group Inc. notified Southern Nuclear Operating Company, operator of the plant, that it had discovered that some of its contract employees had not been included in the Fitness for Duty pool, as required by NRC regulations. The update said that significantly more than the 20 individuals previously not in the pool had been discovered, and that the problem now “rises to the level of a programmatic vulnerability.”

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About Robert Singleton

By day, I work for a call center. In my spare time, I try to save my hometown (and planet) from a nearly constant onslaught of greedheads, lunatics and land developers. I live in a fictional town called Austin, Texas, where I go to way too many meetings.
This entry was posted in Coolant leak, Earthquake, Event Reports, Expansion, Fitness for Duty, North Anna, Nuclear Regulatory Commission, Plant shutdowns, Reactor problems, Salem, Southern Co., Vogtle and tagged , , , , , , , , , , , . Bookmark the permalink.

2 Responses to Event Reports: A reactor trip in New Jersey, bad welds and an earthquake in Virginia and continued Fitness for Duty problem at nuke construction site in Georgia

  1. Patricia Steinhauer says:

    Mr. Singleton, your post about the trip at Salem 2 makes no sense. Auxiliary feedwater always starts following a reactor trip from 100% power because the turbine-driven main feed pumps lose their motive power (steam extracted from the main turbine flowpath). “23 of 24 reactor pumps failed to energize”? There are no such pumps. 23 and 24 reactor coolant pumps were running, but when the plant trips, the electrical source for power busses swaps to the switchyard. Because of ongoing maintenance on a transformer, that swap did not allow the busses for 23 and 24 reactor coolant to energize, so the pumps tripped AS DESIGNED. That has nothing whatsoever to do with the fact that auxiliary feedwater pumps started AS DESIGNED.

    Talk sense, man, if you are going to post. Here is the actual text of the NRC event report:

    “Salem Unit 2 has experienced an automatic reactor trip at 1428 hours on 3/23/12.

    “Salem Unit 2 tripped due to a turbine trip above [permissive] P-9. All shutdown and control rods fully inserted on the reactor trip.

    “At the time of the trip 22 station power transformer [SPT], the 2F and 2G 4KV group buses were not energized causing a loss of 23 and 24 reactor coolant pumps. The auxiliary feedwater (AFW) system auto-started to provide feed to the steam generators.

    “The crew entered EOP-TRIP-1, then transitioned to the EOP-TRIP-2 and stabilized the plant. Salem Unit 2 is currently in Mode 3 at normal operating temperature and pressure with 21 and 22 reactor coolant pumps in service.

    “There are no shutdown technical specifications in effect. All ECCS and ESF systems are available. Decay heat removal is being provided by 21 and 22 AFW pumps and the main steam dump system. The plant is aligned with a normal electrical line-up from offsite power sources with the exception of 22 SPT. Restoration of the 22 SPT and 2F and 2G 4KV group buses is in progress.

    • Ms. Steinhauer: Thank you for catching the factual error in this post. I was working from the Event Report you cited, but misread “23 and 24” as “23 of 24.” I have corrected the sentence in the post to read: “During the incident, two reactor coolant pumps were unavailable, due to a pair of electrical buses that failed to energize, causing an auxiliary feedwater system activation.”

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