IR 05000483/1987028

Insp Rept 50-483/87-28 on 870824-0911.Violation Noted Re Failure to Identify & Correct Incorrect Essential Svc Water Valve Position.Major Areas Inspected:Essential Svc Water Sys Operability

ML20235K146
Person / Time
Site:	Callaway
Issue date:	09/25/1987
From:	Hinds J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20235K145	List: IR 05000483/1987028 ML20235K143
References
50-483-87-28, NUDOCS 8710020256
Download: ML20235K146 (7)

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U. S. NUCLEAR REGULATORY COMMISSION

REGION III

Report No. 50-483/87028(DRP)

Docket No. 50-483 License No. NPF-30 !

Licensee: Union Electric Company Post Office Box 149 - Mail Code 400 4 St. Louis, MO 63166 Facility Name: Callaway Plant, Unit 1 Inspection At: Callaway Site, Steedman, M0 Inspection Conducted: August 24 through September 11, 1987 Inspector: B. H. Little  ;

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Approved By: J. f. Hinds, hief o9 25 B7 Reactor Projects Section 1A Date Inspection Summary Inspection on August 24 through September 11, 1987 (Report N /87028(DRP))

Area Inspected: A special unannounced safety inspection by the Senior Resident Inspector regarding the essential service water system operabilit Results: One apparent violation was identified (failure to promptly identify and correct an incorrect essential service water valve position - paragraph 2).

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' DETAILS

,. Persons Contacte *J. D. Blosser, Manager, Callaway Plant l '*J. R. Peevy, Assistant Manager, Technical Services

• M. E. Taylor, Superintendent, Operations

• J. C. Gerhart, Superintendent, Quality Assurance Operations Support

• T. P.-Sharkey, Supervisor, Complianc *T. H. McFarland, Superintendent, Design Control

• C. D. Naslund, Manager, Operations Support

• J. L. Cunningham, Shift Supervisor

• W. F. Stubblefield, Superintendent, Administrative Services

• Denotes those present at one or more exit interview In addition, other members of the operations and engineering staffs were contacte . Inspection of the Essential Service Water System Operability Background On August 15, 1987, the licensee's operating crew determined that valve EF-V-0117 (Essential Service Water [ESW] train "B" to the Ultimate Heat Sink [ UHS] isolation valve) was partially shut, resulting in a "B" train flow rate of 11,000 gpm. The design flow specified in the Final Safety Analysis Report (FSAR) is 13,594 gp The valve actuator position indicator showed that valve EF-V-0117 was in the locked open position; however, the valve stem indicator indicated that the valve was partly closed. This valve position mismatch was previously identified on Work Request (WR) No. 024695 dated May 14, 1984. It appears that knowledge of the valve's

. position deficiency was lost through subsequent WR reissue, review oversights, and WR voidin On. August 20, 1987, an engineering evaluation concluded that, although it was functional, the ESW "B" train had been inoperable since 1984 on the basis that the FSAR design flow rate had not been met, and that the plant had unknowingly entered Technical Specification (T/S) 3.0.3 during occasional periods when the ESW

"A". train had been inoperable. Upon making the inoperability determination, the licensee notified the NRC of the event using the Emergency Notification System (ENS).

A special safety inspection by the senior resident inspector was performed to assess the licensee's activities associated with the incorrect position of the ESW isolation valv The inspection included the following:

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Review of associated documentation: plant records, work <

requests,. a temporary modification, surveillance procedures, i and an incident repor Interviews with licensee personnel from the following departments: Compliance, Engineering, Planning, Scheduling, and Operations, Inspection Findings (1) Event Chronology April 1984 The ESW system preoperational test was complete May 11, 1984 The manual actuator on valve EF-V-0117 (WR No. 8517) was replaced. The WR specified that the valve be stroked as a " retest."

May 14, 1984 WR No. 024695 was issued to adjust the actuator stops of valve EF-V-0117. The WR identified that the " valve would not shutoff" and that the " position indicators on gland (stem) and on manual operator contradict each other." Condition Tag No. 1556 was hung on EF-V-011 May 25, 1984 The retest (stroking) of valve EF-V-0117 (WR No. 8517) was deleted. Followup action was specified as WR No. 02469 June 30, 1984 The ESW "B" pump baseline test (ASME Section XI) was performe August 10, 1984 The plant first entered Mode 4 (ESW required operable per T/S).

May 16, 1986 WR No. 58783 was issued to repair the broken output shaft on the manual operator for valve EF-V-108 (ESW "A" train isolation valve). The WR was revised to install Temporary Modification (TM) No. 86M-041 in lieu of repair of the valve actuato May 17, 1986 TM No. 86M-041 was installed on EF-V-10 June 10, 1986 WR No. 59421 was written to remove the manual operator from valve EF-V-0117 for inspection to assist the engineering evaluation of the broken operator on EF-V-0108. The initiating document was Nonconforming Material Report (NMR) N I-0032 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

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September 9, 1986 WR No. 024695 was voided; the reason provided was " work not required per system l engineer." This voiding may have been done '

because the later issued WR No. 59421 would negate the adjustments. The deficiency ,

relating to the indicator mismatch was not i documented on the later WR and was apparently  !

overlooked. Voiding the WR resulted in removal of the Condition Tag No. 1556 and precluded the licensee's ability to track and resolve the valve EF-V-0117 position deficienc '

September 10, 1986 WR No. 59421 was voided; the reason stated as "not required per new disposition of NMR 86-I-00328." The initial disposition was to repair the valve operator (EF-V-108)

onsite; the disposition subsequently changed to send the operator to the manufacturer for failure analysis and replacement or repai October 24, 1986 Work on WR No. 58408 was completed. The work performed included the removal of TM 86M-041 from and the replacement of the actuator on EF-V-10 August 15, 1987 EF-V-0117 was found partially closed by equipment operators during verification of the ESW valve lineup. The valve lineup was in response to observed low pressure values during the containment cooler flow verifica-tion tes Valve EF-V-0117 was opened, and the correct valve position was verified by stem indica-tion and system flow. The event was documented in Incident Report (IR) No. 87-14 August 20, 1987 An engineering evaluation of ESW "B" train operability concluded that the ESW "B" train had been functional but inoperable since 1984, and that the plant had unknowingly er.tered T/S 3.0.3 on those occasions when the ESW "A" train was inoperable for routine surveillance testing and maintenanc The licensee notified the NRC of the event using the EN (2) Document Review The SNUPpS FSAR, Chapter 9 provides the description of the ESW system and the ESW system flow requirements. During normal plant operations, the ESW receives water from the Service Water System (SWS) and supplies water to the safety-related

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components and air compressors. After cooling the equipment, l the heated water is returned to the SWS. Following a design basis accident or a loss of offsite power, the safety-related

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signals will isolate the ESWS from the SWS by closing the associated motor-operated isolation valves. Also, the ESW pumps will automatically start receiving power from the preferred power supply or from the emergency diesel generators and supply water from the ultimate heat sink to the safety-related components and air compressors. The minimum flow rates required to remove heat from the containment and necessary safety-related components from a postulated loss of coolant accident (LOCA) or main steam line break and dissipate it to the ultimate heat sink are listed in Table 9.2-3 of the FSA The minimum flow requirement specified for ESW train "B" is 13,594 gp Technical Specification (T/S) Limiting Condition For Operation (LCO) 3.7.4 requires that "at least two independent essential service water (ESW) loops shall be operable" while in Modes 1, 2, 3, and 4. T/S action requires that "with only one ESW loop OPERABLE, restore at least two ESW loops to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />."

The Callaway Plant first entered Mode 4 on August 10, 198 T/S surveillance requirements do not require ESW train or system flow verificatio The specified surveillance associated with the ESW system have been satisfactorily performed. These include monitoring of ESW pump performance (obtained by closing down on the pump discharge valve), verification of containment cooler flow rates, and routine verification of valve position (excluding locked valves). Operation Department Procedure ODP-4 (Locked Component Control) specifies that for locked open valves the handwheel or operator be moved in the close direction enough to verify valve movement. Then the valve is returned to its oripJnal position. This procedure has routinely been performed each plant outag The operator indicator, the most visible eno convenient indication of valve position, is utilized during this activit The valve position mismatch j would not likely be identified during performance of this '

procedur On August 15, 1987, the ESW train "B" degraded flow condition was identified during an ESW system valve lineup review. The lineup was performed in response to low pressure readings observed during performance of the containment cooling water flow surveillance (T/S 4.6.2.3.a.2). Operating crew members found valve EF-V-0117 locked open as indicated by the valve actuator position indicator, but actually partially shut (valve stem indication). The as-fougd ESW train "B" flow rate (control room flow meter) was 5.5 x 10 Lbm/hr (approximately 11,000 gpm). The valve was opened and verified open by correct flow indication. Incident Report (IR) No.87-148 was issued to document the even __---_______J

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f-A preliminary engineering evaluation of the as-found flow l' rate was performed to assess ESW train "B" operabilit Based I

on the evaluation, the licensee determined that the degraded flow condition resulted in train "B" being inoperable but functional since 1984. Based on the preliminary engineering assessment and informal discussions with Bechtel, the licensee believes that the as-found flow rate was adequate to perform the specified safety function, although less than the FSAR design value. The licensee has authorized Bechtel Corporation to perform a detailed safety analysi ~

Through the review of plant records and interviews with licensee personnel, the inspector was not able to determine the actual date valve EF-V-0117 was incorrectly positione However, a satisfactory pre-operational test of the ESW system was performed in April 1984. A subsequent ESW "B" pump baseline test, performed in June 1984, provides pump data which indicates that the valve was partially shut. There was no requirement to compare "A" train and "B" train data. Such a comparison would have detected the "B" train flow deficienc Multiple work requests were issued to document deficiencies on valves EF-V-0117 and EF-V-0108 (see Event Chronology). It appears that some WRs were voided to eliminate duplicate WRs, and in the process all deficiencies were not retained on replacement WR WR No. 024695, issued May 14, 1984, documented the deficient valve position indication; however, the deficiency was not corrected, and on September 9, 1986, the WR was voide The incorrect actuator position indicator caused the valve to be placed in, and locked in, a partially closed position and resulted in a degraded flow condition of ESW train "B". The degraded flow condition existed from approximately May 1984 to August 15, 1987, and resulted in an unanticipated reduction in the safety margin. The licensee's failure to promptly correct the valve position deficiency is a violation of 10 CFR 50 Appendix B, Criterion XVI, " Correct Action."

3. Licensee's Corrective Action Completed Action The valve actuator has been caution trgged to alert operators to the problem and to ensure that the local indicator on the valve stem is used for position indication until the actuator is repaired during Refuel I Engineering personnel involved in voiding the WRs have been counsele It was emphasized that thorough research be done prior to authorizing the voiding of any WR. Thorough research prior to voiding a WR is presently a plant-wide accepted policy. This would include retests. In addition, it is now required by procedure that the reason for voiding a WR be given along with the name of the person voiding the WR. This will also provide traceability between WR _ _ - - _ - _ - - _ -

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J Planned Action This event will be added to the required reading list for all system engineer Engineers involved with ASME Section XI evaluations were reminded to recognize the effect on the total system when re-establishing pump baselines. This event will be reviewed by the planner The failure of personnel to properly prioritize the work on the valve indicators initially is considered an isolated cas To provide edditional assurance that this is an isolated case, a review of voided and open WRs will be performed. This review will ensure that operability concerns have been properly identified and prior-itize A review of the WR control program indicated weakness in the WR voiding process. The current procedure requires additional information on the reason for voiding work documents. In addition, the procedure will be revised to require that appropriate information is transferred from a voided WR to the current WR which implements previously uncompleted wor An ESW System Total Flow Verification test will be performed during Refuel II to verify total ESW system flows for trains "A" and "B" in the event of a LOC . Safety Significance The ESW system consists of two independent 100-percent capacity train The ESW "A" train was fully operable while the ESW "B" train flow was restricted, except for durations of approximately one day per month to support maintenance and surveillance testing. A preliminary assess-ment by the licensee indicates a high probability that the "B" train flow rate was adequate to perform the specified safety functio The event posed no significant threat to the public or plant safety, based on the independent capacity of the ESW trains and the low probability of an event involving the ESW system occurring during the periods that only the "B" train was available. However, the event is considered significant based on the licensee's failure to control and correct a knowi, deficiency in a timely manner, the unanticipated reduction in margins of safety, and the entry into a condition prohibited by Callaway Technical Specification . Exit Interview The inspector met with licensee representatives (denoted under Persons Contacted) at intervals during the inspection period. The inspector summarized the scope and findings of the inspection. The licensee representatives acknowledged the findings as reported herein. The inspector also discussed the likely informational content of the inspection report with regard to documents or processes reviewed by the inspector during the inspection. The licensee did not identify any such documents / processes as proprietar