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Secondary Containment is the last barrier to stop the release of radiological material. It is typically called the Reactor Building
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| ENS 49565 | Susquehanna | 21 November 2103 03:40:00 | Secondary Containment Fails Drawdown Surveillance Testing | On November 20, 2013 at 2240 (EST), secondary containment drawndown testing surveillance failed to meet acceptance criteria SR 3.6.4.1.5 due to maximum flow rate exceeding the allowable value.
SSES (Susquehanna Steam Electric Station) previously entered SR 3.0.3 at 0900 on 11/15/2013 due to not meeting SR 3.6.4.1.4 and SR 3.6.4.1.5 because of an untested alignment of the 101 bay with ventilation aligned as a no zone during past performances of the drawdown testing surveillance. The surveillance being performed on 11/20/2013 was testing this previously unsurveilled alignment.
Upon failure of the surveillance, secondary containment ventilation was realigned to the previously tested 818 hatch alignment.
Upon restoration of secondary containment ventilation to a known operable alignment, secondary containment LCO 3.6.4.1 was cleared and operability restored.
This event is being reported under 10 CFR 50.72(b)(3)(v)(c) and per the guidance of NUREG 1022, Rev. 3 section 3.2.7 as a loss of a Safety Function. There is no redundant Susquehanna Secondary Containment System.
The licensee has placed administrative controls on the 101 bay doors to prevent loss of secondary containment during the investigation to determine the reason for the surveillance test failure.
The licensee has notified the NRC Resident Inspector. | | ENS 56980 | Peach Bottom | 19 February 2024 15:45:00 | Loss of Reactor Building Ventilation | The following information was provided by the licensee via email:
At 1045 EST, on 2/19/2024, during a maintenance activity, a loss of all reactor building ventilation occurred on Unit 2. With no flow past the ventilation radiation monitors, the radiation monitors were inoperable to support their ability to perform primary and secondary containment isolation functions or start the standby gas treatment system. Reactor building ventilation was restored within 15 minutes. Due to this inoperability, the radiation monitor system was in a condition that could have prevented fulfillment of a safety function; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v).
There was no impact on the health and safety of the public or plant personnel.
The NRC Resident Inspector will be notified.
- * * RETRACTION ON 3/15/24 AT 1315 EDT FROM BILL LINNELL TO ADAM KOZIOL * * *
Upon further investigation, it was verified that the reactor building and the refueling floor radiation monitors are not needed to control the release of radiation for events described in chapter 14 of the updated Final Safety Analysis Report. For the analyzed loss of coolant accident (LOCA), the primary and secondary signals for this purpose were available and unaffected by this event. The radiation monitors provide a tertiary redundant method that is not credited within the station analysis. For all other analyzed accidents, the signal provided by the radiation monitors is not needed, as the secondary containment isolation function and start of the standby gas treatment system are not credited. Additionally, the fuel handling accident was not credible during the time of the event because no activities were in progress on the refueling floor. Therefore, the threshold for reporting the issue as an event or condition that could have prevented the fulfillment of a safety function was not met.
The NRC Resident Inspector has been notified.
Notified R1DO (Jackson) | | IR 05000333/2023004 | FitzPatrick | 7 February 2024 | Integrated Inspection Report 05000333/2023004 and Independent Spent Fuel Storage Installation Inspection Report 07200012/2023001 | | | ML23286A278 | | 2 February 2024 | Watermarked - DG-5075 - Cyber Security 10-13-23 | | | IR 05000382/2023010 | Waterford | 31 January 2024 | Comprehensive Engineering Team Inspection Report 05000382/2023010 | | | ML24003A770 | | 18 January 2024 | Monthly (28-day) Federal Register Notice - Applications and Amendments to Facility Operating Licenses and Combined Licenses Involving No Significant Hazards Considerations - Publication Date: January 23, 2024 | | | IR 05000373/2023012 | LaSalle | 18 January 2024 | County Station - Biennial Problem Identification and Resolution Inspection Report 05000373/2023012 and 05000374/2023012 | | | L-MT-23-054, Subsequent License Renewal Application Supplement 8 | Monticello | 11 January 2024 | Subsequent License Renewal Application Supplement 8 | | | ML23334A201 | Cooper | 3 January 2024 | Issuance of Amendment No. 274 Revision to Technical Specifications to Adopt TSTF-551, Revision 3, Revise Secondary Containment Surveillance Requirements | | | NUREG-2175, February 2024 ACRS Meeting - Predecisional - Documents to Support SECY-24-XXXX - Draft NUREG-2175, Revision 1 | | 20 December 2023 | February 2024 ACRS Meeting - Predecisional - Documents to Support SECY-24-XXXX - Draft NUREG-2175, Revision 1 | |
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