Updated Aug 8:
LOWER ALLOWAYS CREEK TWP. — The Salem 2 nuclear reactor has returned to service after a brief shutdown, a company official said.
According to Joe Delmar, spokesman for the plant's operator, PSEG Nuclear, the unit began sending electricity back out over the regional power grid at 7:39 a.m. Sunday.
Salem 2 automatically shut down at 3:39 p.m. Wednesday because of an electrical circuit failure on one of the four reactor coolant pumps.
When any of those four pumps — which circulate cooling water around the reactor vessel — fails, it automatically causes the reactor to trip off-line.
Workers traced that pump circuit failure to an electrical issue with a drain pump which removes condensed water off of the turbine on the non-nuclear side of the plant.
The drain pump tripped and a relay switch did not function properly causing the electrical circuit failure on the one reactor coolant pump...
Updated on Aug 6:
Is it a electrical problem, detector or a frozen reactor coolant pump or motor?
***Salem reactor shut down by electrical problem
How come the NRC never discloses why the licencees reduced the maintenance?
Why didn't the NRC pickup this change in maintenance frequency and write up a NRC report on it before the breaker failure? Why isn't the NRC anticipatory instead of reactionary?
Just saying, on my River Bend special inspection, there has been a widespread breakdown in GE Magne-Blast breaker reliability over maintenance issues. I am sure is is not limited to breaker (Salem), but a global maintenance financial issue across the whole plant and across whole fleets of plants.
Just as the NRC expressed it in the finding concerning broad "Equipment Reliability" and entry into LCOs...an increasing trend in equipment failures outside the breaker failure. How bad is this going to get?
Broken bolts found in all of PSEG Nuclear's Salem 2 reactor cooling pumps LOWER ALLOWAYS CREEK TWP.
PSEG Nuclear has now found broken-off bolt pieces inside all four of the huge pumps which help cool the nuclear reactor at its Salem 2 plant, officials said.We seen this a last year with their poor maintenance on the Reactor coolant pumps with nut/bolts breaking off and entering the coolant. It cost them a tremendous amount of money with the plant staying off the line. I am just saying with penny pinching, it takes a delay time for the equipment failure to show up. Then when the plant is reflooded with monies for the proper maintenance, it takes a long time to fix the degraded parts and do all the proper maintenance with equipment failures still occurring.
Errant bolt heads have been found in the bottom of the reactor coolant pumps and even at the bottom of the reactor core itself, settled under the nuclear fuel rods.
And some of the bolt heads that have broken off have not yet been accounted for, federal regulators confirmed Tuesday.
The bolts secure parts known as turning vanes on the inside of the pump. The vanes direct water out of the pump into the reactor where it circulates to cool the core.
This kind of licencee behavior puts the community at risk...
July 28, 2015
SUBJECT: SALEM NUCLEAR GENERATING STATION, UNIT NOS. 1 AND 2 –INTEGRATED INSPECTION REPORT 05000272/2015002 AND 05000311/2015002
*Equipment Reliability
The inspectors identified that an increasing trend of equipment failures was having an apparent impact on the ability of PSEG to meet station CAP goals. Specifically, the inspectors noted that there has been a steady increase in the number of unplanned LCOs (that exceeded station goals) and CAP evaluation products, as well as CAP evaluation products and actions that fell below station goals for quality and timeliness.
PSEG has identified an adverse trend in equipment deficiencies, as evident by the following notifications captured in CAP, dating back to September of 2014.
*Annual Sample: 12 Safety Injection Pump Breaker Failure to Close
a. Inspection Scope
The inspectors performed an in-depth review of PSEG’s evaluations and corrective actions associated with notification 20660365 and ACE 70168725 for an August 27, 2014 failure of the 12 SI pump breaker to close on demand while attempting to refill the 14 SI accumulator. The limiting conditions for operations could not be met as provided in the associated action requirements, because the system had no operable SI pumps available due to the 11 SI pump being out of service for routine maintenance. PSEG realigned, tested, and returned the 11 SI pump into service, then transitioned into TS
LCO 3.5.2.b for meeting the action statement of having one SI pump available. PSEG performed an ACE and determined the most probable cause of the failure was due to the lack of lubrication inside the breaker close latch roller. The apparent cause was determined to be not proactively addressing timely overhauls of the breakers.
The inspectors assessed PSEG’s problem identification threshold, problem analysis, extent of condition reviews, compensatory actions, and the prioritization and timeliness of PSEG's corrective actions to determine whether PSEG was appropriately identifying,
characterizing, and correcting problems associated with this issue and whether the planned or completed corrective actions were appropriate. The inspectors compared the actions taken to the requirements of PSEG's corrective action program and 10 CFR 50, Appendix B, Criterion XVI, “Corrective Action” and 10 CFR 50, Appendix B, Criterion V, “Instructions, Procedures, and Drawings.”
Findings and Observations
The inspectors concluded that PSEG took appropriate actions to identify the cause of the August 27, 2014, 12 SI pump breaker failure. The inspectors determined that the breaker failure was due to inadequate overhaul intervals of the 4kV breakers.
During review of the 12 SI pump breaker trip event, the inspectors noted that the breaker’s recent operating history had, in effect, changed its classification under PSEG’s ER-AA-1001, “Component Classification,” Revision 2. Specifically, the breaker had originally been classified as a critical, low duty cycle, mild environment component. However, inspectors noted that a high duty cycle was defined, in part, as one where the component is cycled frequently (i.e. greater than two times per week). From late 2014, the 14 accumulator had been experiencing leakage. From that time through the first half of 2015, the frequency at which the 12 SI pump was started to refill the accumulator steadily rose. In the few months leading up the failure, the number of accumulator fills with the 12 SI pump increased until its usage was three times a week for the two weeks prior to the failure. Essentially, PSEG had changed the breaker’s classification by changing its operational frequency to compensate for accumulator leakage. A review
of PSEG’s maintenance template for the same breaker as a high duty cycle component was the same as that for a low cycle breaker. Therefore, the inspectors concluded that this issue was minor. However, they also concluded that PSEG missed this as an opportunity to identify a change in the circumstances surrounding the breaker’s operation. PSEG captured this in their CAP as notification 20664925.
Introduction. A self-revealing Green NCV of 10 CFR 50, Appendix B, Criterion V, “Instruction, Procedures, and Drawings,” was identified because PSEG did not establish an appropriate interval to overhaul 4kV GE Magne-Blast breakers. As a result, the safety-related breakers for the 12 safety injection pump and 11 CCW pump were operated beyond the industry recommended overhaul interval and subsequently failed.
Analysis. The performance deficiency associated with this finding was that PSEG did not establish an appropriate interval to overhaul the 4kV GE Magne-Blast breakers. This finding is more than minor because it is associated with the equipment performance attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, PSEG did not consider industry recommendations nor develop a basis when establishing 4kV GE Magne-Blast breaker overhaul intervals, which resulted in failure of the 12 SI pump and 11 CCW pump breakers. In accordance with IMC 0609.04, “Initial Characterization of Findings,” and Exhibit 2 of IMC 0609, Appendix A,
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