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LER 97-013-00:on 971110,failure to Closure Test Two Check Valves Resulted in Violation of TS 6.5.7 Occurred.Caused by Close Function for Check Valves.Check Valves Tested to Confirm Proper Closure Capability
	ML18065B115
Person / Time
Site:	Palisades
Issue date:	12/09/1997
From:	Kozup C; CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	;
Shared Package
ML18065B114	List: ML18065B113; ML18065B115;
References
	LER-97-013, LER-97-13, NUDOCS 9712160379
	Download: ML18065B115 (6)
	v • d • e

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NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150~104 (4/95) EXPIRES 4/30/98 ESTIMATED ll.IUJ0j PER RESPONSE TO COllPL Y WITH THIS llNIDATORY INFORllATION COUECTION REQUEST: !50.0 HRS. REPORTED LESSONS LEARNED ARE INCORPORATED lllTO THE LICENSING PROCESS Nill FED BACK TO INDUSTRY. FORWARD COllllEllTS LICENSEE EVENT REPORT (LER) REGARDING BURDEN ESTIMATE TO THE INFORllATION Nill RECORDS llANAGEllEllT 8RND1 (T~ F33), U.S. JU:LEAR REGULATORY COlllllSSION, WASHINGTON, DC~

0001, Nill TO THE PAPERWORK REOUC'TION PROJECT (3150-0104, OFFICE OF

..;. (See reverse for required number of digits/characters for each block) llANAGEllEllT Nill BUDGET, WASHINGTON, DC 20503 DOCKET NUMBER (2) Page (3)

FACILITY NAME (1) CONSUMERSENERGYCOMPANY PALISADES NUCLEAR PLANT 05000255 1of6

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TITLE (4) LICENSEE EVENT REPORT 97-013 - FAILURE TO CLOSURE TEST TWO CHECK VALVES RESULTS IN A VIOLATION OF TECHNICAL SPECIFICATION 6.5.7 EVENT DATE (5) LER NUMBER (6) REPORT DATE (7) OTHER FACILITIES INVOLVED (8)

MONTH DAY YEAR YEAR I SEQUENTIAL NUMBER I REVISION NUMBER MONTH DAY YEAR FACILITY NAME DOCKET NUMBER 05000 FACILITY NAME DOCKET NUMBER 11 10 97 97 - 013 - 00 12 09 97 05000 OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check one or more) (11)

MODE(9) N 20.2201(b) 20.2203(a)(2)(v) x 50. 73(a)(2)(i) 50.73(a)(2)(iii)

POWER 20.2203(a)(1) 20.2203(a)(3)(i) 50. 73(a)(2)(ii) 50. 73(a)(2)(x) nn e:: 20.2203(a)(2)(1) 20.2203(a)(3)(ii) 50.73(a)(2)(iii) 73.71 LEVEL (10) 20.2203(a)(2)(ii) 20.2203(a)(4) 50.73(a)(2)(iv) OTHER

- 20.2203(a)(2)(iii) 20.2203(a)(2)(iv)

NAME Charles S. Kozup, Licensing Engineer 50.36(c)(1) 50.36(c)(2)

LICENSEE CONTACT FOR THIS LER (12) 50.73(a)(2)(v) 50.73(a)(2)(vii)

TELEPHONE NUMBER (Include Area Code)

COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

(616) 764-2241 Specify in Abstract below or in NRC Form 366A CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE TONPRDS TONPRDS SUPPLEMENTAL REPORT EXPECTED (14) MONTH DAY YEAR I YES If yes COMPLETE EXPECTED COMPLETION DATE x I NO EXPECTED SUBMISSION DATE (15)

ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) (16)

On November 10, 1997, the plant was operating at 99.6% power. During the evaluation of an NRC Architect-Engineering Design Inspection team request for information, it was determined the check . :..,;

valves (CK-ES3339 and CK-ES3340) in the minimum flow recirculation piping from the discharge of each High Pressure Safety Injection (HPSI) pump were not periodically tested to confirm their closure capability. It was concluded that this is conirary to the requirements of ASME XI and Technical Specification 6.5. 7. The technical concern is an interface between a high pressure and low pressure system not being tested periodically to confirm appropriate isolation. Without such confirmation of isolation, it is postulated that the piping and components with lower pressure rating might be overpressurized. -

Upon discovery, both HPSI pumps and associated check valves were declared inoperable.

Technical Specification 4.0.3, allows for a delay up to 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months to complete the surveillance testing prior to taking the required technical specification action. The check valves were tested to confirm they would close properly. The HPSI pumps and associated components were declared operable and compliance with the technical specifications was restored. The testing was performed without any reduction in plant power level.

9712160379 971209 PDR ADOCK 05000255 S PDR

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LER NUMBER 6)

YEAR SEQUENTIAL REVISION CONSUMERS ENERGY COMPANY I NUMBER NUMBER 05000255 6 PALISADES NUCLEAR PLANT 97 - 013 - 00 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

EVENT DESCRIPTION On November 10, 1997, the plant was operating at 99.6% power. During the evaluation of an NRG Architect-Engineering Design Inspection team request for information, it was determined the check valves (CK-ES3339 and CK-ES3340) in the minimum flow recirculation piping from the discharge of each High Pressure Safety Injection (HPSI) pump were not periodically tested to confirm their closure capability. It was concluded that this is contrary to the requirements of ASME XI and Technical Specification 6.5. 7. The requirements for testing are in Section XI OMa-1988 Part 10 Section 4.3, which specifies the In-Service Testing (IST) requirements for category C check valves. The technical concern is an interface between a high pressure and low pressure system not being tested periodically to confirm appropriate isolation. Without such confirmation of isolation, it is postulated that the piping and components with lower pressure rating might be

overpressurized. Although these check valves were not being tested periodically for the closure attribute, they were being tested regularly for the open attribute per the. ASME XI valve testing program. They also were included in the Check Valve Program which had confirmed th.e satisfactory materiel condition of these valves.

Upon discovery, both HPSI pumps and associated check valves were declared inoperable.

Technical Specification 4.0.3, allows for a delay up to 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months to complete the surveillance testing prior to taking the required technical specification action. The check valves were tested to confirm they would close properly. The HPSI pumps and associated components were declared operable and compliance with the technical specifications was restored. The testing was performed without any reduction in plant power level.

ANALYSIS OF EVENT The general commitment to an inservice testing program per ASME XI is contained in Technic~I

. Specification 6.5.7, but this section does not provide system or component testing requirements.

Identifying components for inclusion in the ASME XI testing scope depends on the plant specific design basis. The detailed IST program consists of a component-by-component determination of required performance attributes and the appropriate testing for those attributes. A key input for the IST program is the Palisades Equipment Database. The Palisades Equipment Database was developed through design reviews and identifies safety-related equipment and their required operating modes.

For check valves CK-ES3339 and CK-ES3340, the components have always been considered safety related for pressure retention and they are in an ASME XI Class 2 system. The required operating configurations in the Palisades Equipment Database have been safety related to open,

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I U.S. NUCLEAR REGULATORY COMMISSION 8

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TEXT CONTINUATION I

FACILITY NAME l1 \ DOCKETI?\ LERNUMBER16l YEAR SEQUENTIAL REVISION CONSUMERS ENERGY COMPANY NUMBER NUMBER 05000255 6 PALISADES NUCLEAR PLANT If 97 - 013 - 00 11 TEXT {If more space is required, use additional copies of NRC Form 366A) (17) but non-safety related for closure for both valves. This initial Palisades Equipment Database design interpretation was documented in 1979. Based on this determination, these particular valves were included in ASME XI IST testing to confirm they will open, but not included in the ASME XI IST testing to confirm closure.

In the late 1980s, a major upgrade to the Palisades IST program occurred. Upgrades for valve testing were based on preliminary Generic Letter 89-04 information. In April 1988, upgrades to EM-09-02 "lnservice Testing of Plant Valves" were completed which included the addition of check valves CK-ES3339 and ES3340 to the scope of the IST program. These check valves were only specified to be tested to confirm they would open per surveillance test Q0-19 "HPSI Pumps and ESS Check Valve Operability Test". An objective of this upgrade to the IST program was to assure that required attributes identified in the Palisades Equipment Database were incorporated into the IST program. The upgrade was not intended to validate or reconstruct the plant's design basis. Therefore, the existing Palisades Equipment Database was used as the basis for determining valve test requirements. The Palisades Equipment Database open/close functions described above were used as the basis for the 1988 program upgrade, which resulted in not requiring a test of the close feature. Had the valves been identified in the Palisades Equipment Database as having a closed safety function, there would have been an IST test to periodically confirm proper closure.

SAFETY SIGNIFICANCE The following postulated scenario creates a potential overpressurization in the HPSI suction piping if the check valves leak. Note that either HPSI pump could apply in this scenario. The case of HPSI pump, P-66A, operating and HPSI pump, P-668, idled will be described, see the attached sketch. This postulated scenario presumes two in-series check valves both leak-by or stick-open, while the check valve on the suction of the idle HPSI pump closes and prevents leakage. The check valves in the common header to the Safety Injection Refueling Water (SIRW)

Tank (CK-ES3331 and CK-ES3332) are extra valves which are not credited with preventing backwards flow, but which are tested to assure they allow normal flow.

The scenario involves a post-accident lineup which occurs after recirculation actuation signal conditions, one HPSI pump running and supplying water to the primary coolant system (PCS), the other HPSI pump turned off, and PCS pressure is just below the shut off head of the HPSI pumps.

The minimum flow recirculation flow path to the SIRW Tank is isolated by the closure of CV-3027 and CV-3056 due to the recirculation actuation signal. Check valves CK-ES3331 and CK-ES3339 are stuck open (assumed because not previously subjected to periodic IST closure tests), allowing backwards flow and pressure to transmit through the idled HPSI pump, P-668, to its suction side

NRC FORM 366a U.S. NUCLEAR REGULATORY COMMISSION 4195 LICENSEE EVENT REfOKT (LER)

TEXT COMTINUATION FACILITY NAMS: (1 l .,. DOCKETt2\ LER NUMBER 6\ PAGE CONSUMERS ENERGY COMPANY PALISADES NUCLEAR PLANT 05000255 YEAR I SEQUENTIAL NUMBER REVISION NUMBER 40F6 97 - 013 - 00 TEXT (If more space 1s required, use additional copies of NRC Form 366A) (17) piping. Check valve CK-ES3168 is closed (assumed because this is confirmed by IST testing) and capable of preventing backwards flow, thereby allowing P-668 suction side piping to be pressurized from the discharge pressure provided by operating HPSI pump P-66A. This check valve backflow leakage scenario results in pressure build up in the idle HPSI pump discharge piping until it would equalize at or near the PCS pressure and in the HPSI suction piping which is potentially subjected to pressure exceeding its design rating of 500 psig. Thus, there exists a possibility of overstressing the piping by applying pump pressure and makes the closure attribute a safety related function for these check valves.

In recognition of th~ importance of these check valves, the IST program has been testing these check valves per ASME XI to confirm they open. In addition, the check valve program has been monitoring these check valves to confirm no degradation of their materiel condition. What was not recognized was the IST requirement to test the closure attribute. In terms of materiel condition of the check valves, there has been no identified degradation. The testing performed confirms the check valves close satisfactorily and there was no backflow leakage. Based on the system design a11d the quality of the components installed in these applications, the need for multiple .failures of in-series components between the discharge of the operating HPSI pump and the suction of the idle pump to result in overpressurization, the pressure retaining capability of materials installed in the suction piping segment, and the as-found satisfactory condition of the check valves, it is concluded that minimal risk of overpressurizing the HPSI pump suction piping existed. Therefore,

the safety consequences were minimal for not routinely testing these check valves per ASME XI for the closed safety function.

CAUSE OF THE EVENT Explicit design information has not existed identifying a need for these particular check valves to be IST tested for closure. The IST staff have used the Palisades Equipment Database for determining required tests, and the Palisades Equipment Database has consistently identified these valves as non-qualified for closure since 1979.

The Palisades* Equipment Database determination of the close function for these check valves was in error because not all possible failure scenarios were considered.

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NRC FQ~{JfA ~l~ilbi* U.S. NUCLEAR REGULATORY COMMISSION 4195; LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION 8

FACILITY NAME f1 l OOCKETf2\ IER NUMBER 161 CONSUMERS ENERGY COMPANY PALISADES NUCLEAR PLANT 05000255 YEAR I SEQUENTIAL NUMBER REVISION NUMBER 6 97 - 013 - 00 TEXT (If more space 1s required, use additional copies of NRC Form 366A) (17)

CORRECTIVE ACTIONS COMPLETED The check valves CK-ES3339 and CK-ES3340 were tested to confirm proper closure capability.

CORRECTIVE ACTIONS TO BE COMPLETED The following actions will be completed:

1. Perform new Palisades Equipment Database safety related interpretations for the check valves (CK-ES3339 and CK-ES3340), revise the Palisades Equipment Database accordingly, and add the closure attribute of the check valves to the In Service Testing program.

2. Review other ASME XI check valves, control valves, and motor operated valves for similar discrepancies in their Palisades Equipment Database or testing scope, and initiate Palisades Equipment Database interpretations and procedure changes, as necessary.

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ML18065B115

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