ML18025B210: Difference between revisions

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{{#Wiki_filter:JAN 2 5 2018 Brad Berryman Site Vice President U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Susquehanna  
{{#Wiki_filter:JAN 2 5 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)/2017-007-00 UNIT !LICENSE NO. NPF-14 UNIT 2 LICENSE NO. NPF -22 PLA-7674 TALEN-4 ENERGY 10 CFR 50.73 Docket No. 50-387 50-388 Attached is Licensee Event Repmt (LER) 50-387(388)/2017-007-00.
: 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)/2017-007-00 UNIT !LICENSE NO. NPF-14 UNIT 2 LICENSE NO. NPF -22 PLA-7674 TALEN-4 ENERGY 10 CFR 50.73 Docket No. 50-387 50-388 Attached is Licensee Event Repmt (LER) 50-387(388)/2017-007-00.
The LER repmts an event which caused a loss of Secondary Containment differential pressure.
The LER repmts an event which caused a loss of Secondary Containment differential pressure.
This event was determined to be reportable in accordance with 10 CFR 50.73(a)(2)(v)(C) as a condition that could have prevented fulfilment of a safety function.
This event was determined to be reportable in accordance with 10 CFR 50.73(a)(2)(v)(C) as a condition that could have prevented fulfilment of a safety function.
Line 27: Line 25:
==Attachment:==
==Attachment:==


LER 50-387(388)/2017-007-00 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 FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES:
LER 50-387(388)/2017-007-00 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 FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 03/31/2020 (04-2017)
03/31/2020 (04-2017)
Estimated burden per response to comply with this mandatory collection r equest: 80 hou r s. LICENSEE EVENT REPORT (LER) Reported l essons l ea rn ed are i n corporated into the licensing process and fed back to industry. Send comments regarding burden es tim ate to the Information Services Branch (T-2 F43), U.S. (See P age 2 for required number of digits/characters for each block) Nuclear Regulatory Commiss i on, Washington, D C 20555-000 1, or by e-ma il t o lnf oco ll ec t s. ...... t-"' Resource@nrc
Estimated burden per response to comply with this mandatory collection request: 80 hours. LICENSEE EVENT REPORT (LER) Reported lessons learned are incorporated into the licensing process and fed back to industry. Send comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. (See Page 2 for required number of digits/characters for each block) Nuclear Regulatory Commission, Washington, DC 20555-000 1, or by e-mail to lnfocollects. ...... t-"' Resource@nrc
.gov, and t o the Desk Officer, Office of Information and Regulatory Affairs, (See NUREG-1 0 22, R.3 for instruction and guidance for completing this form N E OB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to impose a n information co ll ection does n ot display a cur r en tly va lid OMB co nt ro l num ber, httQ://www. nrc.gov/readi ng-rm/doc-colle cti ons/nur§9s/staff/
.gov, and to the Desk Officer, Office of Information and Regulatory  
sr 1 022/r3D the NRC may n ot conduct or sponso r, and a person is n ot required to r espond t o, the information collection.  
: Affairs, (See NUREG-1 022, R.3 for instruction and guidance for completing this form NEOB-10202, (3150-0104),
: 1. FACILITY NAME DOCKET NUMBER .PAGE Susquehanna Steam Electric Station Unit 1 05000387 1 OF2 4. TITLE Secondary Containment Declared Inoperable Due to the opening of a plenum. 5. EVENT DATE 6. LER NUMBER 7. REPORT DATE 8. OTHER FACILITIES INVOLVED SEQUENTIAL FACILITY NAME DOCKET NUMBER MONTH DA Y YEAR Y EAR REV MONTH DA Y YEAR Susqueahanna Steam Electric Station Unit 2 NUMBER NO. 05000388 11 30 2017 2017 -007 -00 01 ..25 2018 FACILITY NAME DOCKET NUMBER 05000 9. OPERATING MODE 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: Check all that apply) 1 D 20.2201(b)
Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, httQ://www. nrc.gov/readi ng-rm/doc-colle ctions/nur§9s/staff/
sr1 022/r3D the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.  
: 1. FACILITY NAME DOCKET NUMBER .PAGE Susquehanna Steam Electric Station Unit 1 05000387 1 OF2 4. TITLE Secondary Containment Declared Inoperable Due to the opening of a plenum. 5. EVENT DATE 6. LER NUMBER 7. REPORT DATE 8. OTHER FACILITIES INVOLVED SEQUENTIAL FACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR REV MONTH DAY YEAR Susqueahanna Steam Electric Station Unit 2 NUMBER NO. 05000388 11 30 2017 2017 -007 -00 01 ..25 2018 FACILITY NAME DOCKET NUMBER 05000 9. OPERATING MODE 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: Check all that apply) 1 D 20.2201(b)
D 20.2203(a)(3)(i) 0 50.73(a)(2)(i i)(A) D 50.73(a)(2)(viii)(A)
D 20.2203(a)(3)(i) 0 50.73(a)(2)(i i)(A) D 50.73(a)(2)(viii)(A)
D 2o.2201{d)
D 2o.2201{d)
Line 45: Line 40:
D 50.73(a)(2)(ix)(A)
D 50.73(a)(2)(ix)(A)
D 20.2203(a)(2)(i) 0 50.36{c)(1)(i)(A) 0 50.73(a)(2)(iv)(A)
D 20.2203(a)(2)(i) 0 50.36{c)(1)(i)(A) 0 50.73(a)(2)(iv)(A)
D 50.73(a)(2)(
D 50.73(a)(2)(x) 10. POWER LEVEL D 20.2203(a)(2)(ii) 0 50.36(c)(1 )(ii)(A) D 50.73(a)(2)(v)(A)
x) 10. POWER LEVEL D 20.2203(a)(2)(ii) 0 50.36(c)(1 )(ii)(A)
D 73.71(a)(4) D 20.2203(a)(2)(iii)
D 50.73(a)(2)(v)(A)
D 50.3 6(c)(2) D 50.73{a)(2)(v)(B)
D 73.71(a)(4)
D 20.2203(a)(2)(iii)
D 50.36(c)(2) D 50.73{a)(2)(v)(B)
D 73.71(a)(5) 100 D 20.2203(a)(2)(iv)
D 73.71(a)(5) 100 D 20.2203(a)(2)(iv)
D 50.46(a)(3)(ii) 1:81 50.73(a)(2)(v)(C) D 73.77(a)(1)
D 50.46(a)(3)(ii) 1:81 50.73(a)(2)(v)(C) D 73.77(a)(1) D 20.2203(a)(2)(v)
D 20.2203(a)(2)(v)
D 50.73(a)(2)(i)(A)
D 50.73(a)(2)(i)(A)
D 50.73(a)(2)(v)(D)
D 50.73(a)(2)(v)(D)
Line 60: Line 51:
D 50.73(a)(2)(i)(B)
D 50.73(a)(2)(i)(B)
D 50.73(a)(2)(vii) D 73.77(a)(2)(ii)
D 50.73(a)(2)(vii) D 73.77(a)(2)(ii)
D 50.73(a)(2)(i)(C) 0 OTHER Specify in Abstract below or in NRC Form 366A 12. LICENSEE CONTACT FOR THIS LER LICENSEE CONTACT NUMBER (Include Area Code) /Nicole PaQiiaro-LicensinQ Specialist-Nuclear Regulatory Affairs k570) 542-6578 13. COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT CAUSE SYSTEM COMPONENT MANU-REPORTABLE CAUSE SYSTEM COMPONENT MANU-REPORTABLE FACTURER TO EPIX FACTURER TOEPIX 14. SUPPLEMENTAL REPORT EXPECTED  
D 50.73(a)(2)(i)(C) 0 OTHER Specify in Abstract below o r in NRC F orm 366A 12. LICENSEE CONTACT FOR THIS LER LI CENSEE CON TA CT NUMBER (Include Area Code) /Nicole PaQiiaro-LicensinQ Specialist-Nuclear Regulatory Affairs k 570) 542-6578 13. COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT CA U S E SYSTEM COMPONENT MANU-REPORTABLE CAUSE SYSTEM COMPONENT MANU-REPORTABLE FACTURER T O EPI X FACTURER T O EPI X 14. SUPPLEMENTAL REPORT EXPECTED 15. EXPECTED MONTH DA Y YEAR YES (If yes, complete 15. EXPECTED SUBMISSION DATE) D NO SUBMISSION 02 23 20 18 DATE ft\BSTRA CT (Umit t o 1400 spaces, i.e., ap pro ximately 15 s in gle-spaced typewritten lin es) On November 30, 2017 at 1026, the Susquehanna Control Room received indication that a loss of Secondary Containment Zone 2 differential pressure had occurred.
: 15. EXPECTED MONTH DAY YEAR YES (If yes, complete  
Control Room operators noted a differential pressure of 0" Water Column (WC) for several seconds, followed by a high differential pressure of 0.5" WC. System differential pressure was restored to normal in 3 minutes. The cause of the pressure swings is under investigation.
: 15. EXPECTED SUBMISSION DATE) D NO SUBMISSION 02 23 2018 DATE ft\BSTRACT (Umit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) On November 30, 2017 at 1026, the Susquehanna Control Room received indication that a loss of Secondary Containment Zone 2 differential pressure had occurred.
Control Room operators noted a differential pressure of 0" Water Column (WC) for several seconds, followed by a high differential pressure of 0.5" WC. System differential pressure was restored to normal in 3 minutes.
The cause of the pressure swings is under investigation.
Zone 2 differential pressures being less than 0.25" WC constitutes a loss of Secondary Containment based on not meeting requirements of Technical Specification (T.S.) 3.6.4.1 Surveillance Requirement 3.6.4.1.1 This condition is being reported in accordance with 10 CFR 50. 73(a)(2)(v)(C) as a condition that could have prevented fulfillment of safety function.
Zone 2 differential pressures being less than 0.25" WC constitutes a loss of Secondary Containment based on not meeting requirements of Technical Specification (T.S.) 3.6.4.1 Surveillance Requirement 3.6.4.1.1 This condition is being reported in accordance with 10 CFR 50. 73(a)(2)(v)(C) as a condition that could have prevented fulfillment of safety function.
This event was reported in ENS 53098 under 10 CFR 50.72(b){3)(v)(c)
This event was reported in ENS 53098 under 10 CFR 50.72(b){3)(v)(c)
There is no redundant Susquehanna Secondary Containment system. There were no actual consequences to the health and safety of the public as a result of this event. NRC FORM 366 (04-2017)
There is no redundant Susquehanna Secondary Containment system. There were no actual consequences to the health and safety of the public as a result of this event. NRC F O RM 366 (04-2017)
NRC FORM 366A (04-2017)
NRC FORM 366A (04-2017)
U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES:
U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 3/31/2020 LICENSEE EVENT REPORT (LER) CONTINUATION SHEET (See NUREG-1 022, R.3 for instruction and guidance for completing this form http://WoNV-J.nr c.gov/readinq-rm/doc-colle c tions/nureas/s ta ff/sr1 0 22/r 3 D 1. FACILITY NAME Susquehanna Steam Electric Station Unit 1 NARRATIVE CONDITIONS PRIOR TO EVENT Estimated burden per r esponse to comply with this mandatory co ll ection request: 80 hours. Reported lessons l earned are incorporated into the licensing process and fed back to industry.
3/31/2020 LICENSEE EVENT REPORT (LER) CONTINUATION SHEET (See NUREG-1 022, R.3 for instruction and guidance for completing this form http://WoNV-J.nrc.gov/readinq
Send comments r egarding burden estimate to the Inf ormatio n SeiVices Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington, DC 20555*000 1 , or by e-m ail to lnf oco lle cts.Resource@nrc.gov, and to the Desk Officer, Office of Inf ormation and Regulatory Aff airs, NEOB-10 202, (3150-0104).
-rm/doc-colle ctions/nureas/s taff/sr1 022/r3D 1. FACILITY NAME Susquehanna Steam Electric Station Unit 1 NARRATIVE CONDITIONS PRIOR TO EVENT Estimated burden per response to comply with this mandatory collection request:
Office of Manag e ment and Budget , Washington, DC 20503. If a means u se d t o im pose a n in f ormatio n co ll ectio n do es n ot display a currently valid OMB control num ber, the NRC may not cond u ct or sponsor, and a person is not req uired to respond to, the information co ll ec ti on. 2. DOCKET NUMBER YEAR 05000387 2017 3. LER NUMBER SEQ UENTIA L NUMB ER -007 REV NO. -00 Unit 1 -Mode 1 , approximately 1 00 percent Rated Thermal Power Unit 2 -Mode 1, approximately 100 percent Rated Thermal Power There were no structures, systems, or components that were inoperable at the start of the event that contributed to the event. EVENT DESCRIPTION On November 30, 2017 at 1026, the Susquehanna Control Room received indication that a loss of Secondary Containment Zone 2 differential pressure had occurred.
80 hours. Reported lessons learned are incorporated into the licensing process and fed back to industry.
Control Room operators noted a differential pressure of 0" Water Column (WC) for several seconds, followed by a high differential pressure of 0.5" WC. System differential pressure was restored to normal in 3 minutes. The cause of the pressure swings is under investigation.
Send comments regarding burden estimate to the Information SeiVices Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington, DC 20555*000 1, or by e-mail to lnfocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104).
Zone 2 differential pressures being less than 0.25" WC constitutes a loss of Secondary Containment based on not meeting requirements of Technical Specification (T.S.) 3.6.4.1 Surveillance Requirement 3.6.4.1. There were no actual consequences to the health and safety of the public as a result of this event. The condition is being reported in accorance with 10 CFR 50.73(a)(2)(v)(C) as a condition that could have prevented fulfillment of a safety function.
Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection. 2. DOCKET NUMBER YEAR 05000387 2017 3. LER NUMBER SEQUENTIAL NUMBER -007 REV NO. -00 Unit 1 -Mode 1, approximately 1 00 percent Rated Thermal Power Unit 2 -Mode 1, approximately 100 percent Rated Thermal Power There were no structures,  
: systems, or components that were inoperable at the start of the event that contributed to the event. EVENT DESCRIPTION On November 30, 2017 at 1026, the Susquehanna Control Room received indication that a loss of Secondary Containment Zone 2 differential pressure had occurred.
Control Room operators noted a differential pressure of 0" Water Column (WC) for several seconds, followed by a high differential pressure of 0.5" WC. System differential pressure was restored to normal in 3 minutes.
The cause of the pressure swings is under investigation.
Zone 2 differential pressures being less than 0.25" WC constitutes a loss of Secondary Containment based on not meeting requirements of Technical Specification (T.S.) 3.6.4.1 Surveillance Requirement 3.6.4.1.
There were no actual consequences to the health and safety of the public as a result of this event. The condition is being reported in accorance with 10 CFR 50.73(a)(2)(v)(C) as a condition that could have prevented fulfillment of a safety function.
This event was reported in ENS 53098 under 10 CFR 50.72(b)(3)(v)(c).
This event was reported in ENS 53098 under 10 CFR 50.72(b)(3)(v)(c).
There is no redundant Susquehanna Secondary Containment system. CAUSE OF EVENT This event is still under investigation
There is no redundant Susquehanna Secondary Containment system. CAUSE OF EVENT This event is still under investigation. The cause will be provided in the supplement.
. The cause will be provided in the supplement.
ANALYSIS/SAFETY SIGNIFICANCE This event is still under investigation. The safety significance will be provided in the supplement CORRECTIVE ACTIONS This event is still under investigation.
ANALYSIS/SAFETY SIGNIFICANCE This event is still under investigation
. The safety significance will be provided in the supplement CORRECTIVE ACTIONS This event is still under investigation.
The corrective action will be provided in the supplement.
The corrective action will be provided in the supplement.
PREVIOUS SIMILAR EVENTS This event is still under investigation.
PREVIOUS SIMILAR EVENTS This event is still under investigation.
Previous similar events will be identified under the supplement NRC FORM 3668 (04-2017)
Previous similar events will be identified under the supplement NRC F ORM 3668 (04-2017)
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Revision as of 04:50, 6 July 2018

LER 17-007-00 for Susquehanna, Units 1 and 2 Regarding Secondary Containment Declared Inoperable Due to the Opening of a Plenum
ML18025B210
Person / Time
Site: Susquehanna  Talen Energy icon.png
Issue date: 01/25/2018
From: Berryman B
Susquehanna, Talen Energy
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
PLA-7674 LER 17-007-00
Download: ML18025B210 (3)


Text

JAN 2 5 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)/2017-007-00 UNIT !LICENSE NO. NPF-14 UNIT 2 LICENSE NO. NPF -22 PLA-7674 TALEN-4 ENERGY 10 CFR 50.73 Docket No. 50-387 50-388 Attached is Licensee Event Repmt (LER) 50-387(388)/2017-007-00.

The LER repmts an event which caused a loss of Secondary Containment differential pressure.

This event was determined to be reportable in accordance with 10 CFR 50.73(a)(2)(v)(C) as a condition that could have prevented fulfilment of a safety function.

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.

B. BenY"man

Attachment:

LER 50-387(388)/2017-007-00 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 FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 03/31/2020 (04-2017)

Estimated burden per response to comply with this mandatory collection r equest: 80 hou r s. LICENSEE EVENT REPORT (LER) Reported l essons l ea rn ed are i n corporated into the licensing process and fed back to industry. Send comments regarding burden es tim ate to the Information Services Branch (T-2 F43), U.S. (See P age 2 for required number of digits/characters for each block) Nuclear Regulatory Commiss i on, Washington, D C 20555-000 1, or by e-ma il t o lnf oco ll ec t s. ...... t-"' Resource@nrc

.gov, and t o the Desk Officer, Office of Information and Regulatory Affairs, (See NUREG-1 0 22, R.3 for instruction and guidance for completing this form N E OB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to impose a n information co ll ection does n ot display a cur r en tly va lid OMB co nt ro l num ber, httQ://www. nrc.gov/readi ng-rm/doc-colle cti ons/nur§9s/staff/

sr 1 022/r3D the NRC may n ot conduct or sponso r, and a person is n ot required to r espond t o, the information collection.

1. FACILITY NAME DOCKET NUMBER .PAGE Susquehanna Steam Electric Station Unit 1 05000387 1 OF2 4. TITLE Secondary Containment Declared Inoperable Due to the opening of a plenum. 5. EVENT DATE 6. LER NUMBER 7. REPORT DATE 8. OTHER FACILITIES INVOLVED SEQUENTIAL FACILITY NAME DOCKET NUMBER MONTH DA Y YEAR Y EAR REV MONTH DA Y YEAR Susqueahanna Steam Electric Station Unit 2 NUMBER NO. 05000388 11 30 2017 2017 -007 -00 01 ..25 2018 FACILITY NAME DOCKET NUMBER 05000 9. OPERATING MODE 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: Check all that apply) 1 D 20.2201(b)

D 20.2203(a)(3)(i) 0 50.73(a)(2)(i i)(A) D 50.73(a)(2)(viii)(A)

D 2o.2201{d)

D 20.2203(a)(3)(ii)

D 50.73(a)(2)(ii)(B)

D 50.73(a)(2)(viii)(B)

D 20.2203(a)(1)

D 20.2203(a)(4)

D 50.73(a)(2)(iii)

D 50.73(a)(2)(ix)(A)

D 20.2203(a)(2)(i) 0 50.36{c)(1)(i)(A) 0 50.73(a)(2)(iv)(A)

D 50.73(a)(2)(x) 10. POWER LEVEL D 20.2203(a)(2)(ii) 0 50.36(c)(1 )(ii)(A) D 50.73(a)(2)(v)(A)

D 73.71(a)(4) D 20.2203(a)(2)(iii)

D 50.3 6(c)(2) D 50.73{a)(2)(v)(B)

D 73.71(a)(5) 100 D 20.2203(a)(2)(iv)

D 50.46(a)(3)(ii) 1:81 50.73(a)(2)(v)(C) D 73.77(a)(1) D 20.2203(a)(2)(v)

D 50.73(a)(2)(i)(A)

D 50.73(a)(2)(v)(D)

D 73.77(a)(2)(i)

D 20.2203(a)(2)(vi)

D 50.73(a)(2)(i)(B)

D 50.73(a)(2)(vii) D 73.77(a)(2)(ii)

D 50.73(a)(2)(i)(C) 0 OTHER Specify in Abstract below o r in NRC F orm 366A 12. LICENSEE CONTACT FOR THIS LER LI CENSEE CON TA CT NUMBER (Include Area Code) /Nicole PaQiiaro-LicensinQ Specialist-Nuclear Regulatory Affairs k 570) 542-6578 13. COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT CA U S E SYSTEM COMPONENT MANU-REPORTABLE CAUSE SYSTEM COMPONENT MANU-REPORTABLE FACTURER T O EPI X FACTURER T O EPI X 14. SUPPLEMENTAL REPORT EXPECTED 15. EXPECTED MONTH DA Y YEAR YES (If yes, complete 15. EXPECTED SUBMISSION DATE) D NO SUBMISSION 02 23 20 18 DATE ft\BSTRA CT (Umit t o 1400 spaces, i.e., ap pro ximately 15 s in gle-spaced typewritten lin es) On November 30, 2017 at 1026, the Susquehanna Control Room received indication that a loss of Secondary Containment Zone 2 differential pressure had occurred.

Control Room operators noted a differential pressure of 0" Water Column (WC) for several seconds, followed by a high differential pressure of 0.5" WC. System differential pressure was restored to normal in 3 minutes. The cause of the pressure swings is under investigation.

Zone 2 differential pressures being less than 0.25" WC constitutes a loss of Secondary Containment based on not meeting requirements of Technical Specification (T.S.) 3.6.4.1 Surveillance Requirement 3.6.4.1.1 This condition is being reported in accordance with 10 CFR 50. 73(a)(2)(v)(C) as a condition that could have prevented fulfillment of safety function.

This event was reported in ENS 53098 under 10 CFR 50.72(b){3)(v)(c)

There is no redundant Susquehanna Secondary Containment system. There were no actual consequences to the health and safety of the public as a result of this event. NRC F O RM 366 (04-2017)

NRC FORM 366A (04-2017)

U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 3/31/2020 LICENSEE EVENT REPORT (LER) CONTINUATION SHEET (See NUREG-1 022, R.3 for instruction and guidance for completing this form http://WoNV-J.nr c.gov/readinq-rm/doc-colle c tions/nureas/s ta ff/sr1 0 22/r 3 D 1. FACILITY NAME Susquehanna Steam Electric Station Unit 1 NARRATIVE CONDITIONS PRIOR TO EVENT Estimated burden per r esponse to comply with this mandatory co ll ection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />. Reported lessons l earned are incorporated into the licensing process and fed back to industry.

Send comments r egarding burden estimate to the Inf ormatio n SeiVices Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington, DC 20555*000 1 , or by e-m ail to lnf oco lle cts.Resource@nrc.gov, and to the Desk Officer, Office of Inf ormation and Regulatory Aff airs, NEOB-10 202, (3150-0104).

Office of Manag e ment and Budget , Washington, DC 20503. If a means u se d t o im pose a n in f ormatio n co ll ectio n do es n ot display a currently valid OMB control num ber, the NRC may not cond u ct or sponsor, and a person is not req uired to respond to, the information co ll ec ti on. 2. DOCKET NUMBER YEAR 05000387 2017 3. LER NUMBER SEQ UENTIA L NUMB ER -007 REV NO. -00 Unit 1 -Mode 1 , approximately 1 00 percent Rated Thermal Power Unit 2 -Mode 1, approximately 100 percent Rated Thermal Power There were no structures, systems, or components that were inoperable at the start of the event that contributed to the event. EVENT DESCRIPTION On November 30, 2017 at 1026, the Susquehanna Control Room received indication that a loss of Secondary Containment Zone 2 differential pressure had occurred.

Control Room operators noted a differential pressure of 0" Water Column (WC) for several seconds, followed by a high differential pressure of 0.5" WC. System differential pressure was restored to normal in 3 minutes. The cause of the pressure swings is under investigation.

Zone 2 differential pressures being less than 0.25" WC constitutes a loss of Secondary Containment based on not meeting requirements of Technical Specification (T.S.) 3.6.4.1 Surveillance Requirement 3.6.4.1. There were no actual consequences to the health and safety of the public as a result of this event. The condition is being reported in accorance with 10 CFR 50.73(a)(2)(v)(C) as a condition that could have prevented fulfillment of a safety function.

This event was reported in ENS 53098 under 10 CFR 50.72(b)(3)(v)(c).

There is no redundant Susquehanna Secondary Containment system. CAUSE OF EVENT This event is still under investigation. The cause will be provided in the supplement.

ANALYSIS/SAFETY SIGNIFICANCE This event is still under investigation. The safety significance will be provided in the supplement CORRECTIVE ACTIONS This event is still under investigation.

The corrective action will be provided in the supplement.

PREVIOUS SIMILAR EVENTS This event is still under investigation.

Previous similar events will be identified under the supplement NRC F ORM 3668 (04-2017)

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