ML18016A344: Difference between revisions

From kanterella
Jump to navigation Jump to search
(Created page by program invented by StriderTol)
 
(Created page by program invented by StriderTol)
Line 3: Line 3:
| issue date = 03/12/1998
| issue date = 03/12/1998
| title = LER 97-021-02:on 980210,identified Failure to Properly Test non-safety Related Pressurizer Porv.Caused by Inadequate Surveillance Test Procedures.Revised Operations Surveillance Test OST-1117 to Include Testing of Subject PORV
| title = LER 97-021-02:on 980210,identified Failure to Properly Test non-safety Related Pressurizer Porv.Caused by Inadequate Surveillance Test Procedures.Revised Operations Surveillance Test OST-1117 to Include Testing of Subject PORV
| author name = VERRILLI M
| author name = Verrilli M
| author affiliation = CAROLINA POWER & LIGHT CO.
| author affiliation = CAROLINA POWER & LIGHT CO.
| addressee name =  
| addressee name =  

Revision as of 05:49, 18 June 2019

LER 97-021-02:on 980210,identified Failure to Properly Test non-safety Related Pressurizer Porv.Caused by Inadequate Surveillance Test Procedures.Revised Operations Surveillance Test OST-1117 to Include Testing of Subject PORV
ML18016A344
Person / Time
Site: Harris Duke Energy icon.png
Issue date: 03/12/1998
From: Verrilli M
CAROLINA POWER & LIGHT CO.
To:
Shared Package
ML18016A343 List:
References
LER-97-021, LER-97-21, NUDOCS 9803180350
Download: ML18016A344 (5)


Text

NRC FORM 366 ILB5)U.S.NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)(See reverse for required number of digitslcharacters for each block)APPROVED BY OMB NO.3150 0104 EXPIRES 04I30/96 ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS MANOATORT WfORMATION CO(LECTIN REDDEST: 506 HRS.REPORTED (ESSONS lEARHEO ARE INCORPORATED WTO THE UCENSING PROCESS AND FEO BACK TO INDUSTRY.fORWARD COMMEHTS REGAROWG BURDEN ESTIMATE TO THE WfORMATNN AHO RECORDS MANAGEMENT BRANCH IT 6 f33L US NUClEAR REGUlATORY COMMISSION, WASHWGTON.

DC 20555000l, AHO TO THE PAPERWORK REDUCTION PROJECT (3150.OI04L Off)CE'F MANAGEMENT ANO BUDGET, WASHINGTON.

OC 20503.FACIUTY NAME ll)Harris Nuclear Plant Unit-1 DOCKET NUMBER (2)50-400 PAGE (3)1 OF 5 TITLE (4)Technical Specification Surveillance Procedure Review Project Identified Deficiencies.

EVENT DATE{5)MONTH OAY YEAR LER NUMBER (6)YEAR SEOUENTIAL NUMBER REVISION NUMBER REPORT DATE{7)MOIITH OAY YEAR FACIUTY NAME OTHER FACILITIES INVOLVED (6)DOCKET NVMBER 2 10 98 97-021-02 3 12 98 FACILITY NAME DOCKET NUMBER 05000 OPERATING MODE (9)POWER LEVEL{10)100%THIS REPORT IS SUBMITTED PUR 20.2201(b) 20.2203(B)(1) 20.2203(B)(2)(i) 20.2203(B)(2)(ii)SUANT TO THE REQUIREMENTS OF 10 CFR 6: (Check one o 50.73(B)(2)(i) 20.2203(B)(2)(v) 50.73(B)(2)(ii) 50.73(B)(2)(iii) 50.73(B)(2)

Uv)20.2203(a)(3)(il 20.2203(B)

(3)(iil 20.2203(B)(4) r more)(11)50.73(a)(2)(viii)50.73(B)(2)(x) 73.71 OTHER 20.2203(B)(2)(iii)20.2203(B)

(2)(iv)50.36(c)(1) 50.36(c)(2)LICENSEE CONTACT FOR THIS LER (12)50.73(B)(2)

{v)50.73(a)(2)(vii)

Specify in Abstract below or in NRC Form 366A NAME TELEPHONE NUMBER (Inetude Area Code)Michael Verrilli Sr.Analyst-Licensing (919)362-2303 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT{13)CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE TO NPRDS CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE TO NPROS SUPPLEMENTAL REPORT EXPECTED (14)YES{If yes, complete EXPECTED SUBMISSION DATE).X NO EXPECTED SUBMISSION DATE (15)MONTH DAY YEAR ABSTRACT (Limit lo 1400 spaces, i.e., BpproximBtoly 15 single.spaced typowri((en lines)(16)On August 14, 1997, with the plant at approximately 100%polver in mode I, a condition was identiTied during the on-going Technical Specification (TS)Surveillance Procedure Review Project related to inadequate maintenance of Spent Fuel Pool water level.Specifically, Technical Specification (TS)3/4.9.11 requires that"at least 23 feet of water shall be maintained over the top of irradiated fuel assemblies seated in the storage racks." This depth of water will provide sufficient"scrubbing" to remove 99Fo of the assumed 10%iodine gap activity released from the rupture of an irradiated fuel assembly.Contrary to this requirement, water level has not been verified greater than 23 feet above the boiling water reactor (BWR)fuel assemblies received from CP&L's Brunswick Plant, which are currently stored in the Harris Plant fuel pools.These BWR assemblies have a bail handle that extends approximately 6 inches above the top nozzle base plate.When the BWR storage racks were installed in 1991, the 23 foot water level reference mark was established from the top nozzle base plate of the BWR fuel seated in the storage racks, not from the top of the bail handles.This approach was determined at the time to be conservative since the base plate elevation exceeds that of the fuel rods which would be the source of any released fission gasses.However, verbatim compliance with the TS requirements would require 23 feet of water over the BWR fuel assembly structure, including the top bail handle.This condition was caused by a misinterpretation of TS requirements and design mputs during the establishment of the 23 foot water level reference mark and the subsequent setup of water level indicators, when the BWR fuel storage racks were initially installed at the Harris Plant.Corrective actions included directions to Operations to maintain and monitor fuel pool level at or above 23 feet 7 inches to ensure required water level over the BWR bail handles.This was completed by issuing an Operations ni)Eight order and revising the daily surveillance procedures.

Additional actions will include reviewing this event with appropriate Engmeering personnel to emphasize the importance of verbatim TS compliance and an evaluation of the fuel pool level alarm setpoints.

This revision is submined to report an additional condition identified during the on-going Technical Specification Surveillance Procedure Review Project.This condition involved the failure to properly test the non-safety related Pressurizer Power Operated Relief Valve (1RC-116), which resulted in a violation of TS surveillance requirements.

9803180350 9803i2 PDR ADQCK 05000400, S PDR KRC FORM 366A I4.99I LICENSEE EVENT REPORT (LER)TEXT CONTINUATION US.NUCLEAR RECULATORT COMMISSION FACIIITT NAME In Shearon Harris Nuclear Plant-Unit//1 OOCRET 50400 lER NUMBER IBI SEOUENTIAL RDtISION NUMBER NUMBER 97-021-02 PACE 13I 2 OF 5 TEN'r pr moro spooo N rorfrri od.oso oddn ooof oopris of HRC form ZEQI (I 7)EVENT DESCRIPTION:

On August 14, 1997, with the plant at approximately 100%power in mode 1, a condition was identified during the on-going Technical Specification (TS)Surveillance Procedure Review Project related to inadequate maintenance of Spent Fuel Pool water level.Specifically, Technical Specification (TS)3/4.9.11 requires that"at least 23 feet of water shall be maintained over the top of irradiated fuel assemblies seated in the storage racks." As described in the TS Bases section for this TS, this depth of water will provide sufficient"scrubbing" to remove 99%of the assumed 10%iodine gap activity released from the rupture of an irradiated fuel assembly.Contrary to this, water level has not been verified greater than 23 feet above the boiling water reactor (BWR)fuel assemblies received from CP&L's Brunswick Plant, which are currently stored in the Harris Plant (HNP)fuel pools.These BWR assemblies have a bail handle that extends approximately 6 inches above the top nozzle base plate.When the BWR storage racks were installed in 1988, the 23 foot water level reference mark was established from the top nozzle base plate of the BWR fuel seated in the storage racks, not from the top of the bail handles.This approach was determined at the time to be conservative since the top nozzle base plate elevation exceeds that of the fuel rods which would be the source of any released fission gasses.However, verbatim compliance with the TS requirements would require 23 feet of water over the BWR fuel assembly structure, including the top bail handle.The method of verifying adequate water level in the Spent Fuel Pools at HNP involved confirming that the low-level alarm was not present.The low level alarm setpoint was established at 23 feet 2.5 inches and was consistent with the 23 foot reference mark from the top nozzle base plate.Therefore water levels could have dropped below 23 feet above the top of the BWR assembly bail handles and not result in a low level alarm.The following additional Technical Specification Surveillance related deficiencies have been identified by the on-going comprehensive TS Surveillance Procedure Review Project.The TS Surveillance Procedure Review Project was originally committed to in LER 95-07 dated September 28, 1995.On September 22, 1997, a design deficiency in the Fuel Handling Building Emergency Exhaust System (FHBEES)was determined to be reportable.

Specifically, the FHBEES contains two units (E-12&E-13)which each consist of a fan, charcoal adsorber beds and HEPA filters.To prevent degradation of the charcoal bed removal efficiency, the units contain heaters to control the humidity of the air passing through the charcoal.To prevent potential auto-ignition of the charcoal in the idle unit due to heat from the decay of radionuclides captured by the charcoal, the system is designed to provide cooling flow or"bleed flow" (approximately 5%of total flow)through the idle unit.NRC Reg.Guide 1.52 and the HNP Final Safety Analysis Report (FSAR)section 6.5.1 indicate that the bleed flow passes from the discharge of the idle unit to the suction of the on-line unit.Any releases would thus be filtered through a charcoal filter with the appropriate design efficiency.

Contrary to this, the bleed flow on the FHBEES units passes from the discharge of the idle unit to the discharge of the on-line unit.Since the heaters that control relative humidity do not run when the unit is not in service, the humidity in the idle unit is not controlled.

Therefore, efficiency of the charcoal in the idle unit could potentially be degraded and air flowing through this idle unit c'ould be filtered with an efficiency lower than the assumed 95%contained in the FSAR chapter 15 fuel handling accident analysis.This would have resulted in higher calculated off-site doses had fuel movement occurred as assumed in the FSAR analysis and allowed by plant procedures.

Therefore, this condition is being voluntarily reported as a condition that could have resulted in operation outside the design basis of the plant per 10CFR50.73.a.2.

ii.Also on September 22, 1997, a condition involving inadequate surveillance testing of the FHB and RAB Emergency Exhaust system charcoal adsorber beds was determinied to be reportable.

Specifically, HNP NR M A l4 I NRC FORM 366A I495I LICENSEE EVENT REPORT (LER)TEXT CONTINUATION U.S.NUClEAR REGULATORY COMMISSION FACILITY NAME ui Shearon Harris Nuclear Plant~Unit Nl BUCKET 50400 lER NUMBER IBI YEAR SEOUENTML REYISION NUMBER NUMBER 97-021-02 PAGE I3I 3 OF 5 TEXT pr coro oproo N rorpriod.ooo orrdrreoor oopeo ot rdRC Fore 36atl (IT)EVENT DESCRIPTION: (continued)

Technical Specifications require that a laboratory analysis be performed on the charcoal"after every 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of charcoal adsorber operation".

The hours of operation have only been accumulated based on the time period that the on-line unit was in service.The accumulation should also have included the time that bleed flow was passing through the idle unit.This condition was considered to be a violation of TS surveillance requirements 4.7.6.c and 4.9.12.c.On February 10, 1998, an additional TS testing deficiency was identified during the on-going TS Surveillance Procedure Review Project.This deficiency involved past testing of the non-safety related Pressurizer Power Operated Relief Valve (PORV, 1RC-116, EIIS Code:AB-RV), which was not performed at the correct plant conditions per the requirements of TS surveillance requirement 4.4.4.1.Specifically, TS 4.4.4.l.b states that"each PORV shall be demonstrated OPERABLE at least once per 18 months by: (b)Operating the valve through one complete cycle of full travel during MODES 3 or 4, prior to going below 325 degrees F".Testing to satisfy this surveillance requirement has been performed by the"Pressurizer Safety Grade PORV Operability

-Quarterly Test" Operations Surveillance Test procedure (OST-1117).

Past performance of this test was credited for satisfying the entire TS surveillance requirement.

However, testing of 1RC-116, the non-safety related PORV, was not included in OST-1117.1RC-116 has been tested by the"Pressurizer PORV-Quarterly Operability Test" (OST-1503) to satisfy In-service Inspection requirements.

However, OST-1503 is performed in MODE 5 with Reactor Coolant System temperature less than 200 degrees F.Therefore, 1RC-116 has not been tested in the mode and plant conditions specified by TS 4.4.4.1.b.

The failure to include 1RC-116 in the scope of test procedure OST-1117, occurred during implementation of amendment 27 to the Harris Plant Operating License (TS)in September 1991.This amendment was generated to address the concerns stated in NRC Generic Letter 90-06"Power Operated Relief Valves and Block Valves in PWR Plants".CAUSE: The original condition was caused by a misinterpretation of TS requirements and design inputs during the establishment of the 23 foot water level reference mark (above the BWR top nozzle base plate)and the subsequent setup of water level indicators, when the BWR fuel storage racks were initially installed at the Harris Plant.Cause for Additional Items Identified:

Item 1: The cause of the FHBEES design deficiency was engineering oversight during initial plant design and construction.

Item 2: The cause of the TS surveillance violation related to charcoal testing after 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> of operation was incorrect interpretation of TS testing requirements.

Surveillance test procedures were initially set up to satisfy the 720 hour0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> requirement based on accumulation of hours for the in-service unit only.Item 3: The cause of the pressurizer PORV (1RC-116)testing deficiency was inadequate surveillance test procedures.

The changes made to TS 4.4.4.1 in amendment 27 were not understood by the plant staff and the associated development of OST-1117 did not ensure proper testing of 1RC-116.SAFETY SIGNIFICANCE:

There were no actual safety consequences associated with this event.Adequate water depth (23 feet)has been maintained above the active fuel rods, which would be the source of any released fission gasses.This ensures the iodine removal capability required by TS in the event of a ruptured irradiated fuel assembly.This condition is being reported per 10CFR50.73.a.2.i as a condition prohibited by Technical Specifications.

A (4 NRC FORM 366A)I 96)LICENSEE EVENT REPORT (LER)TEXT CONTINUATION U.S.NUCLEAR REGUULTORT COMMISSION FACIUTT NAME il)Shearon Harris Nuclear Plant Unit 41 BUCKET 50400 LER NUMBER r6)TEAR StaunnML a~ION NUMBER NUMBER 97-021-02 PAGE O)4 OF 5 TEXT Pr rrrrrrs spsss N r rprdsd.sss sdd)s)psl sopis ol PORC Prrrrrr 36@I (I 1)SAFETY SIGNIFICANCE: (continued)

Safet Conse uences for Additional Items Identified:

Item 1: There were no actual safety consequences associated with this additional item.Had a fuel handling accident occurred in the FHB with the improperly configured bleed flow between the filtration units, the resulting off-site dose rates would not have exceeded the maximum value analyzed in the HNP FSAR and would have remained within 10CFR100 limits.This result is based on the fact that fuel off-load during past HNP refueling outages has never occurred prior to 257 hours0.00297 days <br />0.0714 hours <br />4.249339e-4 weeks <br />9.77885e-5 months <br /> following reactor shutdown, which allowed for substantial iodine decay resulting in a lower fuel handling accident source term than that assumed in the FSAR.It is also based on past charcoal efficiency surveillance testing, which has indicated a worst case value of 98%, which is greater than the 95%assumed efficiency value in the FSAR accident analysis.Administrative controls have also been in place to ensure that filter charcoal is replaced if surveillance testing indicates an efficiertcy less than 99%Therefore, this condition is being voluntarily reported as a condition that could have resulted in operation outside the design basis of the plant per 10CFR50.73.a.2.ii.

Item 2: There were no consequences as a result of the TS surveillance requirement violation based on the charcoal surveillance test results described above.This condition is being reported as a condition prohibited by Technical Specifications per 10CFR50.73.a.2.

i Item 3: There were no safety consequences as a result of the pressurizer PORV (IRC-116)testing deficiency.

Testing has been satisfactorily performed per the requirements of TS 4.4.4.l.b to verify the operability of the two safety related pressurizer PORVs (1RC-114 and 1RC-118).This testing ensures that both safety related PORVs would have been available to operators in the event of a Steam Generator tube rupture accident and for use as low temperature over-pressure protection.

This condition is being reported as a condition prohibited by Technical Specifications per 10CFR50.73.a.2.i.

PREVIOUS SIMILAR EVENTS: There have been no previous events related to inadequate verification of Spent Fuel Pool water level or improperly configured bleed flow between air handling units as a result of design oversight.

HNP submitted LER 96-002 to report numerous deficiencies caused by incorrectly interpreting TS testing requirements during initial surveillance test development.

These were a result of HNP's actions to address NRC Generic Letter 96-01.CORRECTIVE ACTIONS COMPLETED:

1.Directions were provided to Operations to maintain and monitor Spent Fuel Pool water level at or above 23 feet 7 inches to ensure required water level over the BWR bail handles.This was completed by issuing an Operations Night Order on August 14, 1997, revising the Reactor Auxiliary Building Operator Logs on August 25, 1997 and requiring the actual Spent Fuel Pool water level to be entered in the daily surveillance requirement test, rather than the previous practice of confirming the absence of the low level alarm.2.This event was reviewed with appropriate Engineering personnel to emphasize the importance of verbatim TS compliance.

This was completed on October 6, 1997.CORRECTIVE ACTIONS PLANNED: l.A Technical Specification (TS)Change Request will be submitted to the NRC to revise TS 3.9.11 to require that the Spent Fuel Pool water level be maintained at least 23 feet over the top of the irradiated"fuel rods" and not"fuel assemblies".

The Technical Specification Change Request will be submitted prior to June I, 1998.NR M)I I NRC FORM 366A I4 95I LICENSEE EVENT REPORT (LER)TEXT CONTINUATION U5.NUCLEAR REGULATORY COMMISSION FACILITY NAME II)Shearon Harris Nuclear Plant~Unit 41 BUCKET 50400 LER NUMBER IBI YEAR SEOUENTIAL REYISION NUMBER NUMBER 97-021-02 PAGE I3)5 OF 5 TEXT pr moro spooo N nOoi od.ooo odd Iiimo/oooo of h'RC perm 3664I (Ir)Corrective Actions for Additional Items Identified:

Item 1: A Justification for Continued Operation (JCO)was approved and implemented for the FHBEES bleed flow issue on October 10, 1997.A long term resolution for the improperly configured FHBEES bleed flow issue will be provided via Engineering Service Request 97-00737.This will ensure that the systems satisfy the appropriate FSAR and Reg.Guide 1.52 design requirements and will be completed prior to the next fuel off-load.Item 2: As an interim measure, Operations personnel will record run times on both the in-service filtration unit and the idle filtration unit in the FHB and RAB Emergency Exhaust Systems.This was directed by an Operations Night Order on October 15, 1997.Revisions were completed to operations procedures that require recording run times for FHB and RAB Emergency Exhaust System filtration units (OP-170"Fuel Handling Building HVAC" and OP-172"Reactor Auxiliary Building HVAC").These revisions were completed on October 30, 1997.Item 3: Operations Surveillance Test (OST-1117"Pressurizer Safety Grade PORV Operability

-Quarterly Test")will be revised to include testing of 1RC-116 at the appropriate plant conditions.

This will be completed by June 30, 1998.N M AI4 I