IR 05000275/1986015

Insp Rept 50-275/86-15 on 860428-0502.No Violations Noted. Major Areas Inspected:Operation,Maint & Surveillance Testing of Auxiliary Feedwater Sys.Unresolved Item Re Automatic Feedwater Sys Operability During Pump Maint Identified

ML20206G139
Person / Time
Site:	Diablo Canyon
Issue date:	06/05/1986
From:	Dyer J, Mckee P, Pierson R, Sharkey J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE)
To:
Shared Package
ML20206G120	List: IR 05000275/1986015 ML20206G117
References
50-275-86-15, NUDOCS 8606250089
Download: ML20206G139 (9)

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OFFICE OF INSPECTION AND ENFORCEMENT DIVISION OF INSPECTION PROGRAMS PERFORMANCE APPRAISAL SECTION (PAS) ,

REPORT: 50-275/86-15 DOCKET: 50-275 Licensee N OPR-80 Licensee: Pacific Gas and Electric Company 77 Beale Street, Room 1451 San Francisco, California 84106 Facility Name: Diablo Canyon Unit I Inspection at: Diablo Canyon Site, San Luis Obispo County, California t Inspection Conducted: April 28, 1986 through May 2, 1986 Inspectors: & S/So/f4 J. E. Dyer / IE, Team Leader Date

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R. C. Pierson, IE, II.spection Specialist Date S 16 key, IE, pection Specialist Dite'

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J Approved b _ m 6/6d4 Phillip F. I ee, Chi'ef Date Operating R tor Programs Branch, IE 8606250089 860616 PDR ADOCK 05000275 G PDR i

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l Sunnary:

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j Inspection During the Period of April 28 - May 2,1986 (Report No. 50-275/

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d l Areas Inspected: Routine, unannounced inspection of the operation, maintenance

and surveillance testing of the Unit I Auxiliary Feedwater (AFW) System.

j j The inspection modules numbers 62700, 62702, 61700, 61725, 71707 and 71710 were used for guidance.

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i Results: During this inspection one unresolved item was identified concerning the determination of the Unit I AFW system operability during pump maintenanc .

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DETAILS I Persons Contacted Licensee Personnel

• N. Aiken Operations Shift Foreman S. Bonton Surveillance Test Supervisor

• T. Bennett Technical Services

• J. Boots Chemistry and Radiation Protection Ma lager ,

• E. Conway Personnel and General Services Manager l

• W. Crockett Instrumentation and Controls Maintenance Manager l

• K. Doss On Site Review Group

• S. Fridley Service Operations Supervisor

• J. Giscion Assistant Plant Manager, Technical Services

• T. Grebel Regulatory Compliance Supervisor J. Hinds Regulatory Compliance

• J. Hubble Senior Security Supervisor

• R. Johnson Onsite Licensing Engineer S. Knigge Mechanical Maintenance R. Kohout Safety / Emergency Services Superviser K. Klee Mechanical and Electrical Maintenance

• K. Levitt Materials Services Manager J. McClintock Fire Protection Engineer

• D. Miklush Maintenance Manager I

J. Moldern Operations Training Supervisor

• R. Patterson Assistant Plant Manager, Plant Superintendent P. Rigney Senior Power Production Engineer

• J. Sexton Operations Manager M. Smith Electrical Maintenance

• D. Taggart Quality Support Director

• R. Thornberry Station Manager

• Townsend Assistant Plant Manager S. Watkins Preventive Maintenance Tracking System Coordinator '

• R. Weinberg PG&E News Services

• Womack Plant Engineering Manager NRC Region V Personnel

• M. Padovan Resident Inspector, Diablo Canyon

• Present at Exit Meeting In addition to the above personnel, the NRC inspectors held discussions with various operations, engineering, technical support, maintenance, and admini-strative members of the licensee's staf .

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2. Background The purpose of this inspection was to assess the adequacy of the opera-tions, maintenance, and surveillance testing programs at Diablo Canyon Unit I as they relate specifically to the auxiliary feedwater (AFW)

syste The Unit I AFW system consisted of a 100% capacity turbine-drivimtpump and two 50% capacity motor-driven pumps, all supplied from two seismically qualified water sources: the condensate storage tank (CST) and the fire water tank (FWT). Collectively, these sources provided an adequate supply of water for long term cooling of the reactor, with the CST being the preferred source. The FWT was normally isolated from the pump suction by both manually and motor-operated valves, while the CST was normally in service and could be isolated from the pumps by manually-operated valves located in the pump room. The motor-driven pumps discharged to the steam generators through four electrohydraulic flow control valves, and the turbine-driven pump supplied the steam generators through four motor-operated flow control valve . Maintenance The inspectors reviewed seven maintenance action request (AR) pack-ages for the AFW system to verify that Technical Specifications (TS)

Limiting Conditions for Operation (LCO) were complied with, main-tenance procedures were properly implemented, equipment clearances and system restoration were adequate, and proper post-maintenance testing was conducted. The following maintenance actions were reviewed:

AR A0013612 AFW Pump 1-2 Oil Contamination Corrective Maintenance (12/21/85)

AR A0013613 AFW Pump 1-3 011 Contamination Corrective Maintenance (12/21/85)

AR A0020838 AFW Pump 1-3 Motor Oil Leak (4/3/86)

AR A0204183 FW-1-LCV-115 Valve Actuator Changeout (8/9/85)

AR A0020917 FW-2-LCV-108 Valve Operation Characteristics (9/4/85)

AR A0010742 FW-1-LCV-113 Valve Operation Problems (11/6/85)

AR A0008131 FW-1-LCV-104 Limit Switch Electrical Inspection (10/5/85)

Based upon this review, the inspectors questioned the licensee's determination of pump operability for AFW pumps 1-2 and 1-3 when contaminated oil was found in both pumps in December 1985. The following sequence of events concerning this issue were developed by the inspectors based on interviews with licensee personnel and a review of maintenance documentation, operator logs, and equipment history records:

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Dec. 17-19 A Unit II motor-driven AFW pump was found to have oil contaminated with brass material. Followup inspections of both Unit I and II steam and motor-driven pumps revealed that Unit I motor-driven pumps 1-2 and 1-3 also had contaminated oi *

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Dec. 20 At approximately 2:45 PM the licensee contacted the pump vendor for recommendations stating that they had discovered the outboard rings out of position and excessive brass material in the oil. The licensee also indicated that they had previous slinger ring alignment problems on these pumps. At approximately 5:50 PM motor driven pump 1-2 was declared inoperable for corrective maintenance. The oil slinger ring was found misaligned but both the ring and bearing were undanaged and reinstalled. The oil sump was flushed and refille (ARA 0013612). The pump was returned to service Dec. 21 at 2:24 A Dec. 21 At 8:45 AM motor-driven pump 1-3 was declared inoperable j for corrective maintenance. The oil slinger ring was found damaged and required replacement. The oil sump was flushed and filled (AR A0013613). AFW pump 1-3 was then returned to service at 7:59 P Dec. 24 A licensee root cause evaluation concluded that a high oil sump level caused the slinger ring to " float" and become misaligne Based on the above information, it appeared to the inspectors that the licensee should have declared both pumps inoperable when the oil contamination was found instead of when the pumps were tagged out for maintenance. The licensee had experienced previous slinger ring alignment problems on both the motor and steam-driven AFW pumps which had resulted in pump thrust bearing failure due to loss of lubri-cation. This fact contributed to the inspectors' conclusion that the affected AFW pumps should have been declared inoperable when the oil contamination was foun During the inspection, the licensee could not fully reconstruct the sequence of events and engineering analysis that concerned the maintenance on the motor-driven AFW pump slinger rings. The licensee initiated actions to investigate this problem more fully. This item will remain unresolved pending followup by the NRC Region V Office (50-275/86-15-01).

b. The inspectors reviewed the licensee maintenance procedures to verify technical accuracy with vendor manuals, proper post maintenance testing, conformance with administrative requirements, and that quality control (QC) was adequately involved. The following procedures were reviewed:

NPAP C-40, Revision 3, " General Requirements for Plant Main-tenance Programs" AP D-756, Revision 4, " Maintenance and Surveillance of Electrical Environmentally Qualified (EQ) Equipment"

MP E-53.3, Revision 12, "Limitorque Operator Torque / Limit Switch Replacements and Adjustment"

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MP M-3.2, Revision 3, " Steam Generator Auxiliary Feedwater Pumps Maintenance (6 & 9 stage)"

MP M-51.8, Revision 7. "Limitorque Valve Operator Disassembly Inspection Maintenance and Reassembly" No violations or deviations were identifie The inspectors reviewed the Plant Information Management System t (PIMS) data base as applied to the Unit I AFW system for technical accuracy. This computer data base was recently implemented to prepare maintenance action requests and record equipment material history. The inspectors identified several errors in the data base including incorrect maintenance procedures referenced for certain valves and improper classification of Environmentally Qualified (EQ)

equipment as non-EQ. The licensee was well aware of these problems and was in the process of validating the data base. The inspectors did not find any instances where the incorrect data had resulted in improper maintenance within the plan . Operations The inspectors walked down both trains of the Unit I AFW system to -

verify the construction and configuration with the applicable station drawings and to assess the material condition of the system. The following drawings were used for reference:

o 106703, Revision 11, Sheet 3 (AFW System Piping)

o 106704, Revision. 9, Sheets 2-3 (Main Steam Supply to Steam Driven AFW Pump)

o 106716, Revision 7, Sheets 5 and 7 (Condensate Storage Tank Supply to AFW Pump)

o 106718, Revision 7, Sheet 3 (Fire Water Tank Supply to AFW Pumps).

The inspectors determined that the systems were constructed and lined up in accordance with the above drawings and that the overall material condition of the system was good. The inspectors noted that the level of cleanliness for the AFW system was excellent, and the use of valve and piping identification markings was comprehensive and effectiv However, the following material deficiencies were identified:

(1) The position indication for valve FW-1-121, pump 1-1 suction from the condensate storage tank, did not accurately reflect the actual valve operation. The position indication for this quick-throw manual isolation valve showed that the valve could be operated in either direction from the closed position, when mechanical stops permitted operation in only one direction to {

open the valve. During the inspection, the licensee modified j the valve position indication to reflect actual valve operating characteristic '

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(2) Motor-operated flow-control valve LCV-108 was found backseated contrary to licensee maintenance practices. During the inspec-tion, the licensee cycled the valve under static conditions to verify the valve was not jammed into the backseat. The problems were identified as an improper limit switch setting and the licensee adjusted the switch for proper operatio (3) Electrohydraulic flow-control valve LCV-113 was missing 6 of 10 closure bolts on its plastic face plate. It appeared that this was not a safety issue because the plate was still secured to the valve. During the inspection, the licensee replaced all the missing bolt b. The inspectors reviewed the normal and emergency operating procedures for the Unit I AFW system to verify their technical adequacy and conformance to the system design drawings. The following procedures were reviewed:

o OP D-1:I, Revision 8, "AFW System-Make Available" o OP D-1:II, Revision 7, "AFW System-Alignment Verification for Plant Startup" o OP D-1:III, Revision 10, "AFW System-Shutdown and Clearing" c OP D-1:IV, Revision 4, " Steam Driven AFW Pump-Restart or Make Available After Overspeed Trip" o EP E-2.1, Revision 1, " Alternate AFW Supplies" The inspectors determined that adequate procedural guidance was provided for the alignment, startup, and shutdown of the AFW syste However, the following weaknesses were identified with the procedures:

(1) Procedure OP D-1:IV provided a diagram of an improperly and properly latched turbine overspeed trip device which did not accurately reflect system construction. During the system walkdown, the inspector identified a condition where turbine-driven AFW pump 1-1 appeared to be improperly latched when compared to the diagram provided by the procedure. The licensee relatched the trip mechanism several times and could not fully depress the latch to the base plate. Further review revealed that the turbine could be fully latched without the latch plate being fully depressed and that the diagram did not accurately reflect the design of the latching mechanism. This procedural deficiency did not appear to result in a safety problem as evidenced by the fact that the licensee has had no history of spurious AFW turbine trips. During the inspection, the licensee revised their operating procedure to reflect the actual system desig While exercising the turbine trip mechanism, the licensee ,

identified that their operator training program did not adequately cover the procedure and technique for latching the turbine driven AFW pump The licensee initiated action to

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train all existing operators on this procedure and to incor-porate this training into initial and requalification training program (2) Emergency Procedure (EP) E-2.1 did not require the condensate storage tank (CST) to be isolated after shifting AFW pump supply to the fire water tank (FWT). During the inspection, the licensee could not provide test data or engineering analyses to demonstrate that this configuration would provide adequate supply to the pumps if the CST were empty. The inspectors questioned whether there would be an eductor effect to the pump o suction due to system flows and the pipe configuration which could cause the pumps to lose suction. Licensee procedures required shifting to an alternate source when CST level was 10%

and an alann occurred when CST level was approximately 5%.

These setpoints appeared adequate to ensure that AFW pump suction will be maintained during the transition of source During the inspection, the licensee revised their procedure to isolate the CST from the pumps after transferring supply to the FWT and upon receiving a low level alarm. This would be an interim measure until adequate testing or engineering analyses can be perfonned to demonstrate that AFW pump suction would not be lost with the CST connected in parallel with the FW No violations or deviations were identified in this are . Surveillance Testing The inspectors reviewed the licensee's surveillance program for technical adequacy and to verify that Technical Specification (TS) and Final Safety Analysis Report (FSAP,) requirements were implemented. The following surveillance test procedures were reviewed against system drawings, electrical schematics, and component technical manuals:

STP P-58, Revision ll, " Routine Surveillance Test of Motor-Driven Auxiliary Feedwater Pumps" STP P-68, Revision 11, " Routine Surveillance Test of Steam Driven Auxiliary Feedwater Pumps" STP P-5A, Revision 3, " Performance Test of Motor-Driven Auxiliary Feedwater Pumps" STP P-6A, Revis1on 1, " Performance Test of Steam Driven Auxiliary Feedwater Pumps,,

STP I-56, Revision 3, "STP Calibration of Auxiliary Feedwater Flow Channel 50, 77, 78, 79; loops 3-2, 3-3, 3-4, 3-5"

STP M-16, Revision 4, " Surveillance Test Procedure of Safeguard's Active Component Operation" (Portions applicable to AFW system only)

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The inspectors determined that surveillance requirements for the Unit 1 AFW system were adequately implemented and appeared to meet the licensee's commitments. During the review, the inspectors identified a labeling error on drawing 503088 (schematic diagram for the solid state protection system). Relays X632 and K634 were shown as closing the AFW turbine steam admission valve, FCV-95, when they actually opened FCV-95. The inspectors verified that this drawing error had not been translated into any procedural errors and the licensee initiated actions to correct the discrepanc No violations or deviations were identifie . Unresolved Items An unresolved item is a matter about which more information is required to determine whether it is acceptable or may involve a violation or deviatio . Exit Meeting The inspection team met with the licensee representatives denoted in paragraph 1 on May 2, 1986, and summarized the scope and findings of the inspection activities.

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