05000387/LER-2018-005, Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switches
| ML18214A344 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 08/02/2018 |
| From: | Berryman B Susquehanna |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| LER 2018-005-00 | |
| Download: ML18214A344 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 3872018005R00 - NRC Website | |
text
AUG 0 2 2018 Brad Berryman Site Vice President U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Susquehanna Nuclear, LLC 769 Salem Boulevard Berwick, PA 18603 Tel. 570.542.2904 Fax 570.542.1504 Brad.Berryman@TalenEnergy.com SUSQUEHANNA STEAM ELECTRIC STATION LICENSEE EVENT REPORT 50-387(388)/2018-005-00 UNIT 1 LICENSE NO. NPF-14 UNIT 2 LICENSE NO. NPF-22 PLA-7726 TALEN~
ENERGY 10 CPR 50.73 Docket No. 50-387 50-388 Attached is Licensee Event Report (LER) 50-387(388)/2018-005-00. This LER is reporting two related events involving drifting of Reactor Pressure Steam Dome-Low permissive switches. These events, one at Unit 1 and one at Unit 2, were determined to be reportable in accordance with 10 CPR 50.73(a)(2)(i)(B) as a condition prohibited by Technical Specifications.
There were no actual consequences to the health and safety of the public as a result of this event.
This letter contains no new regulatory commitments.
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B. Berryman Attachment: LER 50-387(388)/2018-005-00 Copy:
NRC Region I Ms. T. E. Hood, NRC Project Manager Ms. L. H. Micewski, NRC Sr. Resident Inspector Mr. M. Shields, PA DEP/BRP
NRC FORM366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 03/31/2020 (04-2018)
, the NRC may not conduct or spcnsor, and a person is not required to respond to, the information collection.
- 13. Page Susquehanna Steam Electric Station Unit 1 05000387 1 OF4
- 4. Title Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switches
- 5. Event Date
- 6. LER Number
- 7. Report Date
- 8. Other Facilities Involved Sequential Rev Facility Name Docket Number Month Day Year Year Month Day Year Susquehanna Steam Electric Station Unit 2 Number No.
05000388 06 05 2018 2018
- - 005
- - 00 08 02 2018 Facility Name Docket Number 05000
- 9. Operating Mode 10 05 2018 Abstract (Limit to 1400 spaces, i.e., approximately 14 single-spaced typewritten lines)
On June 5, 2018, the Unit 1 "B" Reactor Steam Dome Pressure-Low permissive switch was found outside of the Technical Specification (TS) 3.3.5.1 allowable value during testing. Subsequently, on June 6, 2018, the Unit 2 "C" Reactor Steam Dome Pressure-Low permissive switch was found outside of the TS 3.3.5.1 allowable value during testing. Both drifted outside of the lower allowable value which is intended to ensure that the Emergency Core Cooling System (ECCS) injection prevents the fuel peak cladding temperature from exceeding the limits of 10 CFR 50.46.
Based on the information currently available, Susquehanna Steam Electric Station (SSES) believes that the condition existed for longer than allowed by Units 1 and 2, TS 3.3.5.1 and TS 3.5.1. As such, this is a condition prohibited by Technical Specifications and is being reported in accordance with 10 CFR
- 50. 73(a)(2)(i)(B).
The cause is still under investigation. Compensatory actions include the following: calibration using the quarterly calibration procedures will be performed every 45 days on Unit 1 and every 30 days on Unit 2.
Additional corrective actions will be determined following completion of the cause analysis. Causal and corrective action information will be provided in a supplement to this LER.
There were no actual consequences to the health and safety of the public as a result of this event.
NRC FORM 366 (04-2018)
CONDITIONS PRIOR TO EVENT
Unit 1 -Mode 1, approximately 100 percent Rated Thermal Power Unit 2-Mode 1, approximately 100 percent Rated Thermal Power YEAR 2018
- 3. LER NUMBER SEQUENTIAL NUMBER
- - 005 There were no structures, systems, or components that were inoperable at the start of the event that contributed to the event.
EVENT DESCRIPTION
REV NO.
- - 00 SSES had been utilizing Barton 288A switches in the Reactor Steam Dome Pressure-Low channels [EllS System/Component ldentifier/PS] that provide the injection permissive for the Core Spray system [EllS System Identifier: BM] (TS 3.3.5.1, Function 1d) and the Low Pressure Coolant Injection system (LPCI)
[EllS System Identifier: BO] (TS 3.3.5.1, Function 2d). All eight Barton pressure switches were replaced with GE recommended Cameron 288A pressure switches between September 6, 2017 and November 15, 2017 to address drift issues with the Barton switches. The switches were bench tested prior to installation and calibration checked at the time of installation. Subsequent calibration checks were performed at more frequent intervals than the quarterly TS required calibrations.
After replacement of the Barton switches, drift issues have continued. A detailed timeline of events is as follows:
September 20, 2017-the obsolete Barton 288A pressure switch for Unit 2 PIS-B21-2N021C was replaced with aGE recommended Cameron 288A pressure switch.
October 9, 2017-the obsolete Barton 288A pressure switch for Unit 2 PIS-B21-2N021 D was replaced with a GE recommended Cameron 288A pressure switch.
November 15, 2017-the obsolete Barton 288A pressure switch for Unit 1 PIS-B21-1 N021 B was replaced with aGE recommended Cameron 288A pressure switch.
December 5, 2017-Unit 2 PIS-B21-2N021 C and Unit 2 PIS-B21-2N021 D were found outside of the TS 3.3.5.1 allowable value during the calibration check. Both drifted outside of the upper allowable value which is intended to ensure that the reactor dome pressure has fallen to a value below the Core Spray and RHR/LPCI maximum design pressures to preclude over-pressurization of the low pressure systems prior to low pressure injection initiation. Unit 2 PIS-B21-2N021 C exceeded the TS 3.3.5.1 allowable value by 1.3 psi (455.8 psi versus an upper allowable value of 454.5 psi). Unit 2 PIS-B21-2N021 D exceeded the TS 3.3.5.1 allowable value by 2.8 psi (457.8 psi versus an upper allowable value of 455 psi). Both switches were adjusted to within the TS allowable value. These conditions were reported in LER 50-388/2017-010-00 on February 2, 2018.
NRC FORM 3668 (04-2018)
Page 2 of 4 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 03/31/2020 (04-2018)
LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET (See NUREG-1 022, R.3 for instruction and guidance for completing this form http://WVY~N.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1 022/r3D
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. LER NUMBER YEAR Susquehanna Steam Electric Station Unit 1 05000-387 2018 SEQUENTIAL NUMBER
- - 005 REV NO.
- - 00 June 5, 2018 - Unit 1 "B" (PIS-B21-1 N021 B) was found outside of the TS 3.3.5.1 allowable value during testing. The switch drifted outside of the lower allowable value which is intended to ensure that the ECCS injection prevents the fuel peak cladding temperature from exceeding the limits of 10 CFR 50.46.
PIS-B21-1N021B exceeded the TS 3.3.5.1 allowable value by 2.7 psi (417.0 psi versus a lower allowable value of 419.7 psi). The switch was adjusted to within the TS allowable value. This switch had been installed on November 15, 2017 and had been tested on December 7, 2017 and March 6, 2018 with acceptable results.
June 6, 2018-Unit 2 "C" (PIS-B21-2N021 C) was found outside of the TS 3.3.5.1 allowable value during testing. The switch drifted outside of the lower allowable value which is intended to ensure that the ECCS injection prevents the fuel peak cladding temperature from exceeding the limits of 10 CFR 50.46.
PIS-B21-2N021C exceeded the TS allowable value by 1.5 psi (427.0 psi versus a lower allowable value of 428.5 psi). The switch was adjusted to within the TS allowable value. This switch had been installed on September 20, 2017 and tested on October 20, 2017 with acceptable results. The switch drifted outside of the upper TS 3.3.5.1 allowable value limit on December 5, 2017. This switch was subsequently tested on January 4, 2018, February 8, 2018, March 7, 2018, and May 3, 2018 with acceptable results.
Based on the information currently available, SSES believes that the condition existed for longer than allowed by Units 1 and 2, TS 3.3.5.1 and TS 3.5.1. As such, this is a condition prohibited by Technical Specifications and is being reported in accordance with 10 CFR 50. 73(a)(2)(i)(B).
CAUSE OF EVENT
The cause is still under investigation. Further information associated with the cause will be provided in a supplement to this LER.
ANALYSIS/SAFETY SIGNIFICANCE
Information concerning safety significance will be provided in a supplement to this LER.
CORRECTIVE ACTIONS
The following compensatory actions have been taken:
- 1.
Calibration using the quarterly calibration procedures will be performed every 45 days on Unit 1 and every 30 days on Unit 2.
Additional corrective actions will be determined following completion of the cause analysis and will be provided in a supplement to this LER.
NRC FORM 3668 (04-2018)
Page 3 of 4 (04-2018)
U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 03/31/2020 LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET (See NUREG-1 022, R.3 for instruction and guidance for completing this form http://www. nrc. gov/readi ng-rm/doc-collections/nu regs/staff/sr1 022/r3D
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. LER NUMBER YEAR Susquehanna Steam Electric Station Unit 1 05000-387 SEQUENTIAL NUMBER REV NO.
2018
- - 005
- - 00
COMPONENT FAILURE INFORMATION
The switches that drifted are Cameron Model 288A pressure switches.
PREVIOUS SIMILAR EVENTS
LER 50-388(387)/2015-001-01, "Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Steam Dome-Low Switches", dated February 10, 2016.
LER 50-388/2017-010-00, "Condition Prohibited by Technical Specifications Due to Drift of Reactor Pressure Switches", dated February 2, 2018.
NRC FORM 3668 (04-2018)