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 Start dateReporting criterionTitleEvent descriptionSystemLER
ENS 5052712 October 2014 10:00:0010 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual HeatService Water Pumps Inoperable

At 0226 (EDT on 10/12/14), the 25 Service Water Pump Traveling Screen differential pressure transmitter high side valve, 2LD2729-HIV was discovered closed while performing the monthly bubbler blow down activity. The associated 25 Service Water Pump was operable at this time. The differential pressure transmitter high side valve, 2LD2729-HIV, in the closed/discovered position would have prevented the operation of the 25 Service Water Traveling Screen due to high differential pressure. The 25 Service Water Traveling Screen needs to be operable to support 25 Service Water Pump operability. 25 Service Water Pump Traveling Water Screen was restored to operable after differential pressure transmitter high side valve, 2LD2729-HIV was reopened. The station subsequently verified all Unit 1 and 2 high side and low side differential pressure transmitter valves positions were correct. At 0600 (EDT on 10/12/14), it was identified that the last manipulation of differential pressure transmitter high side valve, 2LD2729-HIV was on 9/7/14. Based on the last known manipulation it is assumed that differential pressure transmitter high side valve, 2LD2729-HIV remained closed from that time until the condition was discovered. Review of other activities performed from 9/7/2014 to present determined that surveillance testing of 21 Service Water Pump resulted in 21, 22, and 23 Service Water Pumps being inoperable on 9/18/2014 for several hours. During that surveillance, combined with the mis-positioned instrument valve on 25 Service Water Pump, five of the six Service Water Pumps would have been inoperable which may have prevented the fulfillment of a safety function. This event is being reported under the requirements of 10CFR50.72(b)(3)(v)(B) as 'Any event or condition that at the time of discovery could have prevented the fulfillment of the safety function of systems that are needed to remove residual heat.' The licensee has notified the NRC Resident Inspector. No one was injured as a result of the failure of 25 Service Water Traveling Screen inoperability.

  • * * RETRACTION FROM ROBERT CORDREY TO DONALD NORWOOD AT 1543 EST ON 12/2/2014 * * *

The purpose of this call is to retract event number 50527. On October 12, 2014, at 1307 EDT, notification was made to the NRC Operations Center by Salem Unit 2 reporting a condition under the requirements of 10CFR50.72(b)(3)(v) as 'Any event or condition that at the time of discovery could have prevented the fulfillment of a safety function of structures or systems that are needed to: ...(D) Mitigate the consequences of an accident.' Subsequent to this report, Salem Unit 2 determined that the condition in which the 25 Service Water (SW) pump may have been considered inoperable, in conjunction with the other SW loop being out of service, was not occurring at the time of discovery and was thus not reportable under the reporting requirement of 10CFR50.72(b)(3)(v). Further analysis of the event determined that the valve mis-positioning of the 25 SW pump traveling screen differential pressure transmitter which defeated the auto-start function of the traveling screen, did not impair the safety function of the traveling screen to minimize carryover of debris to the suction of the 25 SW pump. Thus, during the time in question, the 25 SW pump remained operable which maintained one loop of SW operable during the period of time the other service water loop was removed from service for pump testing. One loop of SW with two pumps operable from different safety related buses is capable of performing the safety function of the SW system during a design basis accident. This event is not considered a safety system functional failure and is not reportable to the NRC under the requirements of 10CFR50.72(b)(3)(v) or 10CFR50.73(a)(2)(v). The NRC Resident Inspector has been notified. Notified R1DO (Dentel)

Service water