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{{Adams
#REDIRECT [[05000387/LER-2014-003]]
| number = ML14121A555
| issue date = 05/01/2014
| title = LER 14-003-00 for Susquehanna Steam Electric Station - Unit 1 Regarding Loss of Secondary Containment During Technical Specification SR 3.6.4.1.5 Drawdown Testing
| author name = Franke J A
| author affiliation = PPL Susquehanna, LLC
| addressee name =
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000387, 05000388
| license number = NPF-014, NPF-022
| contact person =
| case reference number = PLA-7168
| document report number = LER 14-003-00
| document type = Letter, Licensee Event Report (LER)
| page count = 5
}}
 
=Text=
{{#Wiki_filter:M AY 0 1 201 4 Jon A. Franke Site Vice President U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 PPL Susquehanna, LLC 769 Salem Boulevard Berwick, PA 18603 Tel. 570.542.2904 Fax 570.542.1504 jfranke@pplweb
.com SUSQUEHANNA STEAM ELECTRIC STATION LICENSEE EVENT REPORT 50-387(388)/2014-003-00 UNIT 1 LICENSE NO. NPF-14 UNIT 2 LICENSE NO. NPF -22 PLA-7168 Docket Nos. 50-387 50-388 Attached is Licensee Event Report (LER) 50-387(388)/2014-003-00.
On March 4, 2014 at 0025 EST, during Technical Specification (TS) surveillance SR 3.6.4.1.5, drawdown testing of Secondary Containment failed to meet acceptance criteria of SR 3 .6.4.1.5 due to maximum flow rate exceeding the allowable value. This event was determined to be reportable as an 8 hour ENS(# 49867) in accordance with 1 0 CPR 50.72(b)(3)(v)(c) for a loss of safety function.
There is no redundant Susquehanna Secondary Containment system. This LER is being submitted in accordance with 10 CPR 50.73(a)(2)(v)(C), for an event or condition that at the time of discovery, could have prevented the fulfillment of the safety function of Secondary Containment to control the release of radioactive material.
There were no actual or potential consequences to the health and safety of the public as a result of these events.
no new regulatory commitments. J. A. ranRe
 
==Attachment:==
 
LER 387(388)/2014-003-00 Copy: NRC Region I Mr. J. Greives, NRC Sr. Resident Inspector Mr. J. Whited, NRC Project Manager Mr. L. Winker, P A DEP/BRP TM NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 01/31/2017 (01*201 4) Estimated burden per response to comply with this mandatory collection request: 80 ho urs.
Reported lessons learned are incorporated into the licensing process and fed back to industry. ':./) LICENSEE EVENT REPORT (LER) Send comments regarding burden estimate to the FOIA, Privacy and Information Collec t ions ... ..........
' .. Branch (T-5 F53), U.S. Nuclear Regulatory Commission , Washington , DC 20555-0001 , or b y (See Page 2 for required number of internet e-mail to lnfocollects
.Resource@nrc.gov , and to the Desk Offi c er, Offi c e of Informa t ion and Regulatory Affairs, NEOB-10202 , (3150-0104
), Office of Management and Budge t , Washi n gt o n , D C digits/characters for each block) 20503. If a means used t o imp o se an informati o n collection does not disp l a y a c urr e ntly v a l id O M B control number , the NRC may n ot conduct or sponsor, and a person is not required to resp o nd to, the information collection. 1. FACILITY NAME 2. DOCKET NUMBER 3. PAGE Susquehanna Steam Electric Station -Unit 1 05000387 1 OF4 4. TITLE Loss of Secondary Containment during Technical Specification SR 3.6.4.1.5 Drawdown Testing 5. EVENT DATE 6. LER NUMBER 7. REPORT DATE 8. OTHER FACILITIES INVOLVED YEAR I SEQUENTIAL I REV FACILITY NAME DOCKET NUMBER MONTH DAY YEAR NUMBER NO. MONTH DAY YEAR Susquehanna Unit 2 0 5000388 FACILITY NAME DOCKET NUMBER 03 04 2014 2014 -003 -00 05 0\ 2014 05000 9. OEPRA11NG 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}
D 50.73(a)(2)(i)(C)
D 50.73(a}(2)(vii)
D 20.2201 (d) D 20.2203(a)(3)(ii)
D 50.73(a)(2)(ii)(A)
D 50.73(a)(2)(viii)(A)
: 10. POWER LEVEL D 20.2203(a)(1)
D 20.2203(a)(4)
D 50.73(a)(2)(ii)(B)
D 50.73(a)(2)(viii)(B)
D 20.2203(a)(2)(i)
D 50.36(c)(1}(i)(A)
D 50.73(a)(2)(iii)
D 50.73(a)(2)(ix)(A)
D 20.2203(a)(2)(ii)
D 50.36(c)(1)(ii)(A)
D 50.73(a)(2)(iv)(A)
D 50.73(a)(2)(x) 100% D 20.2203(a)(2}(iii)
D 50.36(c)(2} D 50.73(a)(2)(v)(A)
D 73.71 (a)(4) D 20.2203(a)(2)(iv)
D 50.46(a)(3)(ii)
D 50.73(a)(2)(v)(B)
D 73.71 (a}(S) D 20.2203(a}(2)(v)
D 50.73(a)(2)(i)(A)
[8]50.73(a)(2)(v)(C) 0 OTHER D 20.2203(a)(2)(vi)
D 50.73(a)(2)(i)(B)
D 50.73(a)(2)(v)(D)
Spe ci fy in Abstract bel ow or in NRC Form 366A 12. LICENSEE CONTACT FOR THIS LER FACILI TY NAME rELEPHONE NUMER (Include Area Code) Brenda W. O'Rourke.
Senior Er,..,;'"'""'
Nuclear Affairs (570) 542-1791 13. COMPLETE ONE UNE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT CA USE SYSTEM COMPONENT MANU-REPORTABLE CAUSE SYSTEM !cOMPONENT MANU-REPORTABLE FACTURER TOEPIX FACTURER TO EPIX 14. SUPPLEMENTAL REPORT EXPECTED 15.EXPECTED MONTH DAY YEAR 0 YES (If yes, complete 15. EXPECTED SUBMISSION DATE) 1:3:] NO SUBMISSION DATE ABSTRACT (Limit to 1400 spaces , i.e., approximately 15 single-spaced typewritten lines) On March 4, 2014 at 0025 EST, during Technical Specification (TS) surveillance SR 3.6.4.1.5, drawdown testing of Secondary Containment failed to meet acceptance criteria of SR 3.6.4.1.5 due to maximum flow rate exceeding the allowable value. The testing was performed with the Unit 1 Railroad Bay aligned as Zone Ill to verify integrity while aligned in a previously untested alignment.
The untested alignment was with the Unit 2 Reactor Building HVAC shutdown and a controlled Zone II Secondary Containment breech established. Actual in-leakage while in the untested alignment was 3301 cubic feet per minute (cfm), which is in excess of the TS SR 3.6.4.1.5 acceptance criteria of less than or equal to 2885 cfm. This event was determined to be reportable as an 8 hour ENS (# 49867) in accordance with 10 CFR 50.72(b)(3)(v)(c) for a loss of safety function.
There is no redundant Susquehanna Secondary Containment system. This LER is being submitted in accordance with 1 0 CFR 50. 73(a)(2)(v)(C), for an event or condition that at the time of discovery , could have prevented the fulfillment of the safety function of Secondary Containment to control the release of radioactive material.
The direct cause of this event was due to air in-leakage into Secondary Containment past Door-1 01 and the Truck Bay Access Hatch Cover 2H24. The apparent cause was due to inadequate margin for the untested configuration with Unit 2 Reactor Building HVAC shutdown and a controlled Zone II Secondary Containment breach established.
Completed Actions: 1) Secondary Containment ventilation was realigned to a known previously successfully tested alignment, 2) Installed shielding on the Core Spray piping adjacent to the Control Structure to gain margin in SSES's analysis for Control Room Operator dose post-accident, and 3) Revised the Unit 1 and Unit 2 Tech Spec Bases 3.6.4.1 to increase SGTS Exhaust Flow Rate. Planned Actions: 1) Repair/replace the bottom seal plate and the top and bottom seals on Door-1 01, 2) Caulk joints for 2H24 Hatch, and 3) Re-perform Secondary Containment drawdown tests per SE-170-011 for Zone I I Ill aligned in the untested configuration.
There were no actual consequences to the health and safety of the public as a result of this event. NRC FORM 366 (01-2014)
NRC FORM 366A (01*20 14) U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER) CONTINUATION SHEET 1. FACILITY NAME 2. DOCKET Susquehanna Steam Electric Station 05000387 NARRATIVE CONDITIONS PRIOR TO THE EVENT Unit 1 -Mode 1, 100 percent Rated Thermal Power Unit 2-Cold Shutdown, 0 percent Rated Thermal Power APPROVED BY OMB: NO. 3150-0104 EXPIRES: 01/31/2017 Estimated burden per response to comply with this mandatory collection request: 80 hours. Reported lessons learned are incorp o rated into the licensing process and fed back to industry.
Send comments regarding burden estimate to the FOIA , Privac y and In formati o n Collections Branch (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to lnfocollects
.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget , Washington, DC 20503. If a means used to impose an information collection does not display a currently v alid OMB control number , the NRC may not conduct or sponsor, and a person is not required to respond to, the informati o n collection.
: 6. LEA NUMBER 3. PAGE Y EAR I SEQUENTIAL I REVISION NUMBER NUMBER 20F 4 2014 -003 -00 There were no systems, structures, or components that were inoperable prior to the start of the surveillance test that would have contributed to the event. EVENT DESCRIPTION On March 4, 2014 at 0025 EST, during Technical Specification (TS) surveillance SR 3.6.4.1.5, drawdown testing of Secondary Containment failed to meet acceptance criteria of SR 3.6.4.1 .5 due to maximum flow rate exceeding the allowable value. The testing was performed with the Unit 1 Railroad Bay aligned as Zone Ill to verify integrity while aligned in a previously untested alignment.
The untested alignment was with the Unit 2 Reactor Building (RB) HVAC [EllS: VA] shutdown and a controlled Zone II Secondary Containment breech established.
Actual in-leakage while in the untested alignment was 3301 cubic feet per minute (cfm), which is in excess of the TS SR 3.6.4.1.5 acceptance criteria of less than or equal to 2885 cfm. Upon failure of the surveillance, Secondary Containment ventilation was realigned to a known previously successfully tested alignment for Zones I, II and Ill. This alignment consisted of all Reactor Building Zones in service and Zone Ill aligned to the Railroad Bay. On March 4, 2014 at 0128 EST, operability was restored and the Secondary Containment LCO 3.6.4.1 was exited. This event was determined to be reportable as an 8 hour ENS (# 49867) notification in accordance with 10 CFR 50.72(b)(3)(v)(c) for a loss of safety function.
There is no redundant Susquehanna Secondary Containment system. In accordance with 10 CFR 50.73(a)(2)(v)(C), this LER is being submitted for an event or condition that at the time of discovery, could have prevented the fulfillment of the safety function of Secondary Containment to contro l the release of radioactive material.
CAUSE OF THE EVENT The direct cause of this event was due to air in-leakage into Secondary Containment past Door-1 01 [EllS: DR] and the Truck Bay Access Hatch Cover 2H24. The apparent cause was due to inadequate margin for the untested configuration with Unit 2 Reactor Building HVAC shutdown and a controlled Zone II Secondary Containment breach established.
BACKGROUND The Secondary Containment boundary forTS surveillance test SE-170-011 encompasses Zone I and Zone Ill Secondary Containments and will test the Zone I I II and Zone Ill I II boundaries with Zone II at atmospheric conditions (i.e. No-Zone).
Previously, testing per SE-170-011 was performed with Zone II RB HVAC in service, which could influence the amount of in-leakage since Zone II was being maintained at negative 0.32 inch water NRC FORM 366A (01-2014)
NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (0 1*2 014) LICENSEE EVENT REPORT (LER) CONTINUATION SHEET 1. FACILITY NAME 2. DOCKET 6. LER NUMBER YEAR J SEQUENTIAL I REVISION NUMBER NUMBER Susquehanna Steam Electric Station 05000387 2014 -003 -00 NARRATIVE BACKGROUND (cont.) column). Therefore, the boundary components include the following:
: 3. PAGE 3 OF4
* Door-1 01, Unit 1 Reactor Building (RB) Railroad Bay Access Door (Zone Ill to Outside -No-Zone)
* 2H24, 818 Truck Bay Access Hatch, (Zone Ill to Zone II-No-Zone)
* Unit 2 RB Recirculation Dampers, HD27601 A/B, HD27602A/B, and HD27657 A/B Door-1 01 is designed to maintain the RB Secondary Containment boundary when the Railroad Bay is aligned as a secondary containment zone. The 818 Truck Bay Access Hatch Cover 2H24 is used for ventilation separation requirements (Secondary Containment).
The Unit 2 RB recirc dampers are normally closed during normal plant operation with RB HVAC in service. These dampers open on a Secondary Containment isolation signa l (i.e., drawdown surveillance testing, Reactor Protection System swaps, system logic functional testing).
Historically, Secondary Containment testing configuration is two zone operation with Secondary Containmen t isolated on each zone (i.e., RB recirculation fan operating) and with the opposite Unit's normal HVAC system in service. In this configuration, the differential pressures across the recirculation isolation dampers are different than with the opposite Unit's normal HVAC system shutdown.
Operating with the opposite Unit's HVAC in service can cause the Standby Gas Treatment System (SGTS) exhaust flow rate to be:
* Artificially low (leakage through the opposite Unit's exhaust system) or
* High (excessive in-leakage through the opposite Unit supply dampers).
Since the RB recirculation dampers are inspected, the physical leakage characteristics (such as small gaps) should be similar. The main driver of leakage is the differential pressures across the dampers. A review of up test data revealed that with RB HVAC in operation:
* The recirculation supply and exhaust dampers have a differential pressure of approximately 1.5 in wa t er gauge (w.g.)
* The filtered exhaust system has a much larger differential pressure (approximately 8 in w.g.). Due to the large differential pressure, the filtered exhaust dampers provide the largest amount of leakage. Based on the above, the inspection history of the RB Recirculation dampers, the operational history of th e RB (H D27601A/B, HD27602A/B, and HD27657A/B), and the new untested alignment; t he maximum allowable i n-leakage per TS Bases 3.6.4.1 may not be achievable.
AN ALYSIS I SAFETY SIGNIFICANCE Actual Consequences:
Failure of Door-1 01 and the Truck Bay Access Hatch Cover 2H24 to seal properly , along with testing in a previous l y untested alignment with the opposite Unit's RB HVAC shut down, resulted in excessive air in-l eakage into Zone Ill Secondary Containment.
This Secondary Containment testing was performed per TS surveillance procedure SE-170-011 with the Unit 1 Railroad Bay aligned as Zone Ill to verify integrity while performed in a previously untested alignment.
The untested alignment is Unit 2 RB HVAC shutdown with a controlled Zone II Secondary Containme nt breech established. NR C FORM 366A (01-2014)
NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (01*2 014) LICENSEE EVENT REPORT (LER) CONTINUATION SHEET 1. FACILITY NAME 2. DOCKET 6. LER NUMBER YEAR I SEQUENTIAL I REVISION NUMBER NUMBER Susquehanna Steam Electric Station 05000387 2014 -003 -00 NARRATIVE Actual Consequences: (cont.) 3. PAGE 4 OF4 Upon failure of this surveillance, Secondary Containment was re-aligned to a previous successfully tested and operable alignment.
This operable alignment is with jumpers installed per procedure TP-070-020 to electrically cross tie Zone II isolation signal with a Zone Ill isolation signal and a Zone I isolation signal with a Zone Ill isolation signal. Thus, if an isolation on Zone I I Ill or a Zone II I Ill were to occur, a Zone I I II I Ill isolation would be initiated.
Potential Consequences:
In-leakage through both Door-1 01 and the Turbine Building (elevation 818 feet) Truck Bay Access Hatch Cover 2H24, along with Unit 2 RB HVAC shut down, Secondary Containment could have unknowingly been inoperable when Zone II was relaxed from Secondary Containment.
If a Zone I I Ill secondary containment isolation event were to have occurred while in this configuration, resultant accident dose could have exceeded that described in Susquehanna Steam Electric Station's (SSES's) current licensing basis. In summary, there were no actual consequences to the health and safety of the public as a result of this event. CORRECTIVE ACTIONS Completed Actions:
* Installed shielding on the Core Spray piping adjacent to the Control Structure to gain margin in SSES's analysis for Control Room Operator dose post-accident.
In exchange for this gain, the allowable SGTS exhaust flow rate (i.e. Secondary Containment in-leakage) was increased to yield a negligible overall change in Control Room Operator dose. This change in dose strategy allowed the Unit 1 and Unit 2 TS SR 3.6.4.1 .5 Secondary Containment in-leakage acceptance criteria to be increased from 2885 cfm to 4000 cfm.
* Revised the Unit 1 and Unit 2 TS Bases 3.6.4.1 to increase SGTS Exhaust Flow Rate. Planned Actions:
* Repair/replace the bottom seal plate and the top and bottom seals on Door-1 01.
* Install caulk in the joints for the Truck Bay Access Hatch Cover.
* Re-perform Secondary Containment drawdown tests per procedure SE-170-011 for Zone I I Ill aligned in the untested configuration.
* Revise applicable procedures acceptance criteria to new increased SGTS Exhaust Flow Rate values. PREVIOUS SIMILAR EVENTS
* LER 50-387(388)/2013-004-00:
Loss of Secondary Containment
* LER 50-387(388)/2013-005-00:
Loss of Secondary Containment
* LER 50-387(388)/2013-007-00:
Loss of Secondary Containment due to Drawdown Test Failure
* LER 50-387(388)/2014-003-00:
Loss of Secondary Containment due to Failed Solenoid Valve in the Reactor Building Zone I Ventilation Exhaust System NRC FORM 366A (01-2014)}}

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