IR 05000312/1989004

Insp Rept 50-312/89-04 on 890114-0303.Violations Noted.Major Areas Inspected:Operational Safety Verification,Health Physics & Security Observations,Esf Sys Walkdown,Maint,Qa Surveillance & Testing & Followup Items

ML20248J656
Person / Time
Site:	Rancho Seco
Issue date:	03/31/1989
From:	Miller L NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
To:
Shared Package
ML20248J648	List: IR 05000312/1989004 ML20248J646 ML20248J652
References
50-312-89-04, 50-312-89-4, NUDOCS 8904140500
Download: ML20248J656 (13)

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U.-S.. NUCLEAR REGULATORY COMMISSION

REGION V

i Report No: 50-312/89-04 '

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.i LIcenseNo.DPR-54 ,

s Licensee: Sacramento Municipal Utility District

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P. O. Box'15830 Sacramento,; California '95852-1830 Facility:Name: Rancho Seco Unit 1 Inspection st: Herald, Californ'ia (RanchoSecoSite)

Inspection conducted: January 14, 1989 through March 3, 198 Inspectors: A. J. D'Angelo, Senior Resident Inspector P. M. Qualls, Resident Inspector M. M'ller, Reg o al Inspector Approved By: v L.(If./ Miller, Chief Date Signed Reh'ctor ProjectsSection II Summary:

Inspection between January 14 and March 3,1989 -(Report 50-312/89-04)

Areas Inspected: This routine inspection by the Resident Inspectors and in part by Regional Inspectors, involved the areas of operational safety verification, health physics and security observations, engineered safety ,

features system walkdown, maintenance, surveillance and testing, quality j assurance and followup items. During this inspection, Inspection Procedures t 71707, 71710, 61726, 62703, 93702, 92701, and 30703 were use Results: An observed strength was the implementation of a personal heat

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stress program for monitoring personnel working in hot environment i An observed weakness was noted in the conduct of post maintenance testing, the J replacement parts equivalency review, and the completeness of the engineering investigation of the auxiliary feedwater overpressurizatio i l

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8904140500 890331 PDR O ADOCK 05000312 PDC j

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DETAILS l Persons Contacted- Licensee Personnel

J. F. Firlit, Chief Executive Officer, Nuclear

• D. Keuter, Assistant General Manager (AGM), Nuclear Plant Manager ,

J. Shetler, AGM, Plant Support Services

• B. Croley, AGM, Technical Services

• J. Vinquist, AGM, Quality and Industrial Safety

'*D. Brock, Manager,. Nuclear. Maintenance

• S. Redeker, Acting Manager, Nuclear Operations

'*P. Bender, Acting Manager, Materials Management ,

S. Crunk, Manager, Nuclear Licensing '

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R. Baim, Manager, Nuclear Cost Control and Plant Services P. Turner, Manager, Plant Performance

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• M. Bua, Manager,: Radiation Protectio'n

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< J/' Clark, Acting Manager, Chemi'stry

' B.~ Kemper,) Manager,' Scheduling and Outage Management

^* Peabody',' Manager, Nuclear; Engineering-L'. Houghtby, Manager, Nuclear Security

• Herrell, Manager, Nuclear Training

• J. Delezer ski, Supervisor, Incident Investigation ' Review Group (IIRG), Licensing G. Coleman; Quality Engineering Supervisor Other licensee employees contacted included technicians, operators, mechanics, security, and office personne * Attended the Exit Meeting on March 3, 198 . Operational Status of Rancho Seco The plant started this inspection period operating at 30% reactor power on January 14, 1989. The unit increased power to 92% reactor power 'a January 17 and continued operating at that power level until January 31, 198 On January 31, 1989, while performing post maintenance testing of the steam driven Auxiliary Feedwater (AFW) pump, the licensee overpressurized the Auxiliary Feedwater System when the turbine governor failed to control turbine speed, and the steam supply valve to the turbine failed to trip when the turbine oversped. The licensee declared both trains of the AFW system inoperable. The licensee then shutdown the plant to the cold shutdown mod The licensee maintained the plant in cold shutdown while performing maintenance and AFW system inspections for the remainder of the inspection period. A Confirmatory Action Letter dated February 1,1989 from the NRC to the licensee was issued which specified the actions which the licensee committed to perform prior to plant restar A public meeting was held with the licensee at the Rancho Seco site on March 2, 1989 concerning plant restar _ - _ - - _ _ _ _ _ - ___ -

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_ Operational Safety Verification (71707)

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The. inspectors reviewed control room operations which included access control, staffing, observation of system alignments, procedural adherence, and log keeping. Discussions with the shift supervisors and

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operators indicaMd an understanding by these personnel of the reasons ,

for annunciator indications, abnormal plant conditions and maintenance '

work in progress. The inspectors also verified, by observation of valve j and switch position indications, that emergency systems were properly aligned as required by technical specifications for plant condition Tours of the auxiliary,-reactor, and turbine. buildings, including exterior areas, were made to assess equipment conditions and plant conditions. Also, the tours were made to assess the effectiveness of radiological controls and adherence to regulatory requirements. The inspectors also observed plant housekeeping and cleanliness, looked for potential fire and safety hazards, and observed security and safeguards practice In the AFW pump area, assorted tools, temporary fittings and trash were observed on equipment and structural supports. A valve tool with a

" radioactive tool" sticker was observed hung on an I-beam near the AFW pumps, which are not in a radiological control area (RCA). The tool had apparently been overlooked in the AFW pump area when the area had been rezoned to be outside the RCA to permit more efficient work on the AFW pump Licensee personnel surveyed the tool and found it was not contaminate In the RCA, about 30 55 gallon drums labeled "poter cially radioactive liquid" were sitting on grade (gravel) and had no surrounding cofferda Five drums were open, and 3 had 1 inch yellow hoses or 1 inch tygon tubing going in the top opening from the tank farm steam trap sumps. The tygon hoses were full of liquid and pump pulses were evident in the  ;

yellow hose indicating liquid was flowing from the sumps to the dru '

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. licensee personnel were seen near the drums or hoses over a 20 minute time perio The plant manager was informed of the above observation Four days later, the drums were observed in the same plac Licensee personnel were in the area of the drums, although not continuousl The licensee stated that the drums were temporary, that most of them were empty, and that they would be removed around Feburary 25 when the Clean Drain System (CDS) became operable. The sump pump system is still  ;

experiencing startup problems and was being evaluated by engineerin The inspector's concern was that the sump pump system has experienced two series of engineering modifications and continued to fail its performance '

tests due to apparent errors in material selection of the pump The inspector noted that more management attention was required to

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satisfactorily resolve this proble Licensee management assured the inspector that additional attention would be devoted to the syste i ,

During work' activities, it appeared that the health physics managers were conducting plant tours and monitoring work in progress. They appeared aware of significant work which occurred during this perio The

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inspector's Radiation Work Permit (RJ) .revi' we revealed that the RWP did I include: job description, radiation levels, contamination,. airborne

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radioactivity (if expected), respiratory equipment, protective clothing, dosimetry, special; equipment, RWP expiration, health physics (HP) l coverage, and signatures.. The RWP radiation and contamination surveys were kept current. Employees understood the RWP requirement The inspectors observed that personnel in the controlled areas were

, wearing the proper dosimetry and. personnel exiting the controlled areas

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were using the monitors properly. Labeling of containers appeared appropriat Containment building. tours indicated that housekeeping efforts appeared successful in maintaining acceptable cleanliness standards within the building. Health physics coverage within the containment appeared adequate including the control of respiratory protection equipment in us The inspector also noted that the licensee had implemented a personal heat stress program to monitor environmental heat effects upon personnel working within the containment during hot shutdown conditions. The  ;

program monitored all personnel entering and exiting containment with '

measurement of the individuals blood pressure, pulse, body temperature and weight los ;

The inspectors walked down portions of the protected and vital area boundaries to ensure that they were intact and that security personnel were properly posted where known deficiencies existed. The inspectors also observed protected area access control, personnel screening, badge issuing and maintenance on access control equipment. Personnel entering with packages were properly searched and access control was in accordance with licensee procedures. The inspectors observed no obstructions in the isolation zone which could conceal a person or interfere with the detection / assessment system. Protected area illumination appeared adequat No violations or deviations were identifie . ESF System Walkdown (71710)

During the inspection period the inspect' ors walked down the Decay Heat Removal System (DHS) and the Emergency Diesel Generator System (EDS).

The walkdown of the DHS included inspection of the piping and valves inside the containment building. The EDS system walkdown included the mechanical systems within the diesel room and electrical alignment within the diesel and switchgear room The inspectors concluded that: '

All observed hangers and supports were properly made up and aligne Housekeeping was adequate ex' cept as noted in peragraph .

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No' excessive' packing leakage was ob' served on valve ~

Major system components were properly labeled, lubhicated and cooled. No excessive ~1eakage was apparen l

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Instrumentation appeared to be; properly installe 'No tout of calibration gauges were' identifie '

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Flow path components appeared to be in the' correct. positio .

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Required support systems were availabl '

Proper breaker and switch positions'were verifie No violations or deviations were identifie I 5-. Monthly Surveillance Observation (61726) i

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Technica1 specification (TS). required surveillance tests'were observed and~ reviewed to ascertain that they were conducted in accordance with-

. Technical Spec,1fication requirement ~

Thefollowingsurveillanceactivitieswereobservedi fy.,' 4*< : SP;56A . " Variable Diesel Generator (G-886A) .

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ygSynchronizationSurveillanceiTest"

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Implementation of the' licensee!s quarantine and troubleshooting of

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equipment which4potentially had been affected b

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' condition within the. Auxiliary Feedwater (AFW) y the overpressure:

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.The following itenis were considered 'during this review:, testing was in

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.i accordance~with; adequate procedures;.' test instrumentation was calibrated;-

, , limiting conditions for operation were met.; removal'and ' restoration of ~ ,

e the affected components were accomplished; test results confonned with TS 4 and procedure requirements'and were reviewed by personnel..other than the individual' directing the test; the reactor operator, technician or

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engineer performing the. test recorded the data and the data was in 3 agreement with observations made by the inspector, and that.any deficiencies identified during the testing were properly reviewed and resolved by appropriate ma q ement personne No violations or deviations were' identified.-

. Monthly Maintenance Observation / Maintenance Program (62703)

Maintenance activities for the systems and components listed below were observed and reviewed to ascertain that they were conducted in accordance with approved procedures, regulatory guides, industry codes or standards, and the Technical Specifications:

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l Auxiliary Feedwater (AFW) pump maintenance on the pump P-318,

which included the disassembly and inspection of the pump rotating element following the overpressurization even "

Routine maintenance on the "B" Bruce GM Diesel, includirg adjustment of the diesel engine governor. Subsequent maintenance activity discovered that too narrow a band existed between the mechanical overspeed trip and the engine governor speed setpoint. Licensee personne1' widened the band between setpoints and were reevaluating the setpoint tolerances at the end of the inspection ~ perio Troubleshooting of-the "B" Bruce GM Diesel overs'p eed tri Troubleshooting of the AFW system overpressure incident (detailed description in Paragraph 7).

l The following items were considered during this review: The limiting conditions for operation were met while components or systems were  ;

removed from service; approvals were obtained prior to initiating the work; activities were accomplished using approved nrocedures and were j inspected as applicable; functional testing or calibration was performed  !

prior to returning components or systems to service; activities were l accomplished by qualified personnel; radiological controls were implemented; and fire prevention controls were implemente !

a 7. Onsite Followup of Events (93702) 1 On January 31, 1989, after replacing the governor on the turbine driven Auxiliary Feedwater (AFW) pump, P-318, the licensee started the pum When steam was admitted to the turbine by fully opening the steam supply valve, AFW pump speed reached 6020 rpm and remained at this level for 3 minutes. The newly installed governor failed to limit turbine speed to 3600 rpm as required and the turbine overspeed device failed to trip the ,

supply valve at about 4500 rpm as required. The turbine tripped when the .;

personnel controlling the test directed the control room via radio to secure the pump. When the control room operator pushed the shut button, the steam supply valve tripped shut, shutting down the pump. Based on the pump operating characteristics, the licensee calculated that the AFW system had been pressurized to about 3800 psi. The system's normal maximum operating pressure was 1350 psi. The licensee then declared both trains of the Auxiliary Feedwater inoperable, shut down the plant and placed it in cold shutdown, as required by technical specifications, to perform corrective maintenance and engineering evaluation The details of the cause of the failure of the turbine governor and the overspeed trip, post maintenance testing to prevent .urther system overpressurization, and the engineering evaluatior.s and followup are described belo This event and the licensee's followup of it is also described in Inspection Report 89-01, the report of the Maintenance Team Inspectio _

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, Governor Failure Due to having problems with water 1n the governor control oil, on

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January:31, 1989 the licensee. installed a rebuilt Woodward governor on the turbine _ driven'A~uxiliary Feedwater pump, P-318. This rebuilt e governor, a spare from the warehouse, had been rebuilt during 1988 and had several modifications made to it by the vendor during that refurbishmen In-mid-1988, the licensee sent the governor to Woodward for refurbishment, iIn July.1988, the plant. system engineer sent a letter to the Woodward Governor Company requesting that certain improvements be made to the governor during the . refurbishment -

process. . In addition to the changes ~ requested in the letter from the licensee, changes were made to the governor which modified the control oil pressurization system from bi-directional to uni-directional (i.e., clockwise (CW) or counter-clockwise (CCW)).

The governor was. received by the licensee-in September, 1988, and placed in the warehous On September 9,'1988, Woodward prepare'd a Supplier Disposition-Request (SDR) for licensee review. This SDR documented the changes made to the governor at the licensee's request and gave'the refurbished' governor a new part number. The SDR letter did not

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indicate any changes to the governor rotation direction.- It did contain a single data sheet specification list with 32 item entrie One ,of.the 32 entries notes that case rotation is plugged for C ]

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On Septeniber '27,1988, the licensee prepared a Part Equivalency j

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Evaluation: Report (PEER) to evaluate the modified governor prior to '

use, cThe, PEER review failed to recognize the significance of the case rotation notation.in the SDR. In addition, licensee procedures, Rancho,Seco Administrative Procedure (RSAP) 0703, Supplier

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Disposition Request, and Nuclear Engineering Administrative ;

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.thatanEdg(~ NEAP)4202,ProcurementDocumentReview,bothrequireineer1]

PEER ~are for'an item being evaluated as'a replacement part. Had the j

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ECN been initiated, the required 10 CFR 50.59 review would have been !

accomplished. An ECN was not initiated. This is an apparent .)

vjolation'(50-312/89-04-01). ])

.0n January 31, 1989, when the licensee installed and tested the refurbished governor, the governor failed to control the turbine

, s' peed. This failure to control speed was the result of the governor rotatingin.theincorrectdirection(counter-clockwise). Because the governor rotated in the counter-clockwise direction, it did not develop the required internal oil pressure and was, therefore, not able to control turbine speed. This resulted in the turbine .

,, overspeed situation on January 31, 198 ] Failure of Overspeed Trip i

During the pump start, the mechanical overspeed trip device should ! have caused the steam supply valve to the turbine to close at about l

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- 7 4450 rp This action failed to occur. The failure of'the overspeed trip device to function resulted in the overpressurization of the AFW syste Licensee investigation, subsequent to the event, determined that trip rod spring tension was 20 lbs versus the 30 lbs necessary to perform a reliable trip. The licensee concluded that a failure to regularly exercise the overspeed mechanism since July, 1987-contributed to the failure. The licensee further concluded that the failure of the overspeed trip to consistently actuate was attributable to the spring tension being improperly set low at 20 l b s .- The licensee replaced the old spring with one of proper tension and instituted monthly testing of the overspeed trip device -

linkage and trip valve to prevent a recurrenc C. Post Maintenance Test Problems The refurbished governor was installed and tested using Maintenance Work Request (MWR) 0145212D-0. The inspectors reviewed this procedure against the requirements specified in Technical Specification 6.8.1.C and Rancho Seco Quality Manual (RSQM)

Chapter V and Chapter XI. These documents require control of testing using written procedures which require acceptance criteria, requirements and limits from applicable design documents, and instructions for performing the tes The Terry Turbine technical manual described in its governor starting procedure the procedure for a slow start of the turbine by gradually increasing turbine-speed using the throttle supply valve until the governor starts limiting turbine spee It states that

"In an emergency a Terry solid' wheel turbine can be brought up to speed in a few seconds". On-January 31, 1989, the slow, non-emergency start procedure was not contained in the MWR, nor was this procedure contained inslicensee Operations Procedure A.50, Auxiliary Feedwater System. The inspectors concluded that if the vendor manual slow start had been. performed, the AFW system overpressurization might not have. occurred. This appeared to be a violation of the~' procedures which' required adequate written instructions.be provided to conduct a test (50-312/89-04-02).

The inspector also noted the following deficiencies in the maintenance work request:

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MWR 01452120-0 did not include a system valve lineup for the AFW system during this test to limit the portion of the AFW system to the minimum needed to perform the test. It stated only, " Perform the Proper Valve Lineup."

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The licensee did not include in the post maintenance test any l acceptance criteria to use to evaluate satisfactory performance of the newly installed, refurbished governor assembl MWR 04152120 did not include any post installation test requirements for the solenoid dump assembly on the governor, l-l

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,, . . . 8 This assembly opens to dump or relieve control oil pressure in the governor after a turbine trip. A failure of this solenoid to open and relieve control 011' pressure after a turbine overspeed would result in the turbine overspending after the-trip was reset and the turbine restarted. A failure in the-open position would result in the turbine being unable to obtain the required speed to inject AFW into the Once Through Steam Generators (OTSGs).

, The ;icensee vendor manual for the Woodward governor contains a

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warning in two places which states that prior to adjusting an

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installed governor on an operating component, the overspeed

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' ' MWR 01452120, nor was there any directive to check the

overspeed device. The failure of.the overspeed device to

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'S ,;' function contributed significantly to the overpressurizatio 'f<

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These deficiencies were considered to have contributed to the above *

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violatio o ,

s Th'e,MWR. performing the governor post maintenance test was issued by

. the maintenance planner. This procedure was not reviewed by the 4 system engineer;nor by nuclear engineering prior to-implementation as is required"by RQSM Chapter XI. This requirement specifies that test procedures b'e reviewed by the " applicable organizations for technical content". This is an apparent violation (50-312/89-03-03).

During followup of the event, the inspectors identified that a significant contributor to the overpressurization was the control of post-maintenance testing provided by Maintenance Administrative Procedure (MAP)-006. This procedure appeared to give inadequate guidance concerning post-maintenance test preparation, review and performance. As a result, prior to plant restart, the licensee revised MAP-006 to incorporate a much more structured control to direct post-maintenance test activitie Licensee's Engineering Evaluation Plan In response to the Auxiliary Feedwater System overpressurization, the licensee's engineering department responded to the event with an engineering acton plan to determine the effects of the .

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overpressurization. The inspector evaluated the engineering action plan and reveral of the associated actions and calculations. The general.rian was adequate; however, the licensee did not produce more detailed plans for the analysi Since the scope of the analysis was complicated, and was currently well underway, the lack of a more detailed plan appeared to be an oversight. For example, no evaluation had been conducted to determine which piping codes (ANSI or ASME) were administratively applicable for analysi '

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i Apparently, the licensee had not documented the necessary analyses intended to be performed in order to declare the.AFW system operabl ,

Examples of engineering tasks which needed to be performed but were not considered by the licensee were: The licensee had planned to use actual materia 1' physical properties rather than ASME code minimum properties.~ However some material test reports were not found ( 15%) for the piping and components. No further review was planned by the licensee, such as a review of the material specification requirements in order to justify the piping for which records were not locate The necessary reviews were subsequently accomplishe . Measurement of the wall thickness of the 6" buried piping was not considered. The licensee made no contingency plans to measure the 6" buried piping from the inside or the outside of  !

the piping. Even after discussions between inspectors and the i licensee, the licensee did not want to consider the .!

possibility. This eventuality was subsequently considered by the licensee with the result that wall thickness measurements were not accomplished on buried piping. This was an acceptable resolutio . In the calculation of the maximum pressure, the licensee extrapolated pressure values from a pump curve for 3550 rpm to values for 6020 rpm. In the extrapolation, the licensee and the pump vendor agreed that the pump probably cavitated at the higher rpm, and, therefore, the estimate was conservative. The licensee did not address the fact that at high head and low pump flow, inefficiency is high. No consideration was made for a possible change in pump efficiency as a result of. increasing impeller speed. Thus, the extrapolation may not have been l conservative. In a discussion with licensee management, the licensee had used an analytic approach (Affinity Laws) since no actual pump data for the pump speed achieved during the event (6020 rpm) was available. In response to the inspectors'

concern of possible error in determining pump discharge ,

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pressure, the licensee also had determined that the AFW contained two piping elements (a blind flange and an orifice plate) which, analysis showed, would have buckled had the

, system pressure been significantly higher than the licensee's estimate. The two piping elements were inspected and found )

intact. The inspector concluded that the licensee's analysis 1 appeared to be appropriately conservativ l E The licensee did not plan to perform a leak check of the buried piping. Rather, they planned to perform a. hydrostatic pressure

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test. The inspector considered that the buried piping has already been shown to withstand a hydrostatic test pressure and that a leak check would be prudent. After discussions with  !

the licensee, a leak rate check was performed during the hydrostatic tes !

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. 10 .For calculation of the piping pressure stress, the licensee chose to use actual pipe wall thickness as measured in the field using an ultrasonic technique. The licensee had not applied a measurement error factor to their field measurements although such an error factor is. stated in the Operations Manual for the instrument and also' applied during the calibration'of the instrument. After the issue was raised to licensee management, an appropriate error factor was incorporate . The licensee did not initially develop a plan to inspect the coating on the buried piping prior to confirming the coating's integrity. Two excavations were subsequently accomplished for coating inspection. The coating was found to be intac The inspector observed the pump upon disassembly. Shallow impeller scrapes were seen on two of the eight stages. The licensee stated that a i locknut was improperly installed and that the casing and impeller were acceptable for continued servic The licensee measured gasket and

. seating surfaces and determined that the pump casing had not suffered significant damage. The studs'were replaced, as a precaution, although they showed no apparent damage. The inspector concluded that the licensee evaluation of the AFW pump's material condition was adequat The inspector observed that the licensee quickly and effectivel i established the boundary of the overpressurization event. A quarantine was set and evaluation began in a expeditious manner. Initial calculations showed that the estimated pressure would have caused piping hoop stress to be within a. 8 or 9 percent of yield stress for some buried fitting In order to obtain accurate material properties for the buried items, the licensee imediately proceeded to recover the procurement and fabrication. documents of the overpressurized portions of the system. The inspectors observed that the licensee performed the complex task of recovery and evaluation in a thorough and efficient manner. The licensee ,

used an efficient database design which organized and calculated material !

information rapidl The licensee used ASME Boiler and Pressure Vessel Code,Section III, C1hss 3,1977 to show that the system was acceptable for service. The system was designed andu b'ilt to ANSI B31.1, 1968. On February 8 the inspector noted that, although the analysis was underway, the licensee was unable to specifically state the rationale of applying the ASME code-to a system designed originally to ANSI. On February 17, the licensee stated that there was nothing wrong with using two codes, although the licensee was unable to technically justify this statement. On February 22, the licensee provided a copy of a system design criteria which specifically allowed the analysis being done. The inspector reviewed the

. design criteria documents and determined that the analysis underway was being performed in accordance with the requirement The licensee took ultrasonic measurements of the 4" and 6" diameter above ground piping and elbows to calculate the pipe hoop stress experienced during overpressurir M on. The inspector asked if the measurements were repeatable. The insps . tor observed the licensee take duplicate

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measurements and found that some measurements could not be duplicated-because' one of the instrun:ents had a faulty transducer. The licensee inspected the instrument, found the instrument faulty, and re-performed

all of the measurements with a good instrument. Later, the inspector asked the licensee engineering manager if the accuracy.of the UT instrument had been taken into account, and was told that there was complete accuracy in the instrument indication. When licensee quality control personnel were asked the same question, the person showed the inspector the calibrn ion records and calibration procedure for the instrument. The inscrument had an 0: curacy of + or - 0.002 inches. The inspector reviewed the licensee procedure for taking UT measurements (NDE! 6) and found the required accuracy to be + or - 0.001 inch. The licensee agreed to resolve this discrepancy between the procedure stated accuracy and the instrument calibration accuracy by procedure revisio The inspector concluded that this procedure revision resolved the concern over UT measurement accuracy. *

After discussion with the. inspector, the licensee decided to cc -' that the protective coating on the buriedJpiping was intact. Two areu were excavated. The coating was observed to be in excellent condition. The licensee's effort was thorough.-

The licensee evaluated >the effects of the overpressurization on the flanges by performing' finite element analysis.with 'a qualified progra The inspector reviewed the calculation and found it to be conservative and appropriate with respect to the use of symmetry, preload stress, mesh configuration, and sensitivity analysi The inspectors observed the gaskets and studs removed from the flange The gaskets appeared to ha_ve been evenly stressed in the flange with no-

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uneven flange matchup symptoms such as galling or burring. The licensee stated that concern for additional stress introduced by flange misalignment was not' warranted. The inspector concluded that the licensee's analysis was adequat With vt , dor assistance, the licensee determined acceptability of the EFIC block valves. On February 17, the inspector observed that the licensee's plans included disassembly and inspection of the affected valves, including a requirement to use a bluing technique for checking the velve sealing surface fitup. The inspector asks what acceptance criteria for

' bluing the valves would be used. The license < stated that they did not know the original acceptance criteria for valve bluing and that no criteria for bluing was planned. The inspector asked the same question on February 21, when the valve inspection was mostly completed, and the licensee had established an acceptable criteria for valve bluin ,

The licensee returned the AFW system to unrestricted service after replacement of the flange bolts, inspection of the valve internals and flange surfaces, and inspection of a portion of the protective coating material on the piping which is burie Licensee evaluation of the AFW overpressurization event appeared to be adequate to declare the system acceptable for continued operatio However, several critical areas of the licensee's analysis and testing

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,.w ere lac. king in both c' completeness and detail'.- Analysis of piping stress

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/1, 'had begun quickly after the event, but no action plan was developed to .;

f, , ,y identify,all possible engineering options or details needed to fully

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' ' support the chosen approach. ~Therefore,'during the inspection, as stated

' above, six items were identified which directly affected the licensee's f'd ~

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analytical approach but were not initially considered during the

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evaluations.- These items were discussed with licensee management, who

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acknowledged the inspector's concern '

Licensee management _ representatives stated that an action plan was being prepared which incorporated these specific problem areas within the "

engineering department. This plan would be completed by April 1989. The corrective actions to be taken in response to the action plan were to be completed by August 1989. The inspector concluded that the licensee's actions to enhance the quality of engineering and increase personnel accountability were adequate to resolve the concer . Exit Meeting (30703)

The inspector met with licensee representatives (noted in paragraph 1) at various times during the report period and formally on March 3,1989. The scope and findings of the inspection activities described in this report were summarized at the meeting. Licensee representatives acknowledged the inspector's findings.

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