IR 05000295/1987030

Insp Repts 50-295/87-30 & 50-304/87-31 on 871019-23.No Items of Concern Noted.Major Areas inspected:balance-of-plant (Feedwater Sys) in Accordance W/Temporary Instruction 2515/ 83, Balance-of-Plant Trial Insp Program

ML20236U938
Person / Time
Site:	Zion  File:ZionSolutions icon.png
Issue date:	11/24/1987
From:	Danielson D, James Gavula, Holzmer M, Isom J, Jeffrey Jacobson, Lefave W, Szczepaniec A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20236U933	List: IR 05000295/1987030 ML20236U931
References
50-295-87-30, 50-304-87-31, NUDOCS 8712030462
Download: ML20236U938 (20)

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U.S. NUCLEAR REGULATORY COMMISSION

REGION III

Reports No. 50-295/87030(DRS); 50-304/87031(DRS)

l Docket Nos. 50-295; 50-304 Licenses No. DPR-39; DPR-48 l I

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Licensee: Commonwealth Edison Company P.O. Box 767 I Chicago, IL 60690 Facility Name: Zion Station, Units 1 and 2 Inspection At: Zion Site, Zion, Illinois Inspection Conducted: October 19-23, 1987 I

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Inspector t.J. M. Jacobson /r 24//7

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  [mA.J.Szczepaniec   Date d . M. Holzmer    !!/2'4 [67 Date'
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Accompanying Personnel: D. H. Danielson (10/23/87) v/2.a/P7 I

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D. H Danielson, Chief /'/2'7'/f'7 Materials and Processes Section Date Inspection Summary

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Inspection on October 19-23, 1987 (Reports No. 50-295/87030(DRS); \ No. 50-304/87031(DRS)) y Areas Inspected: Special announced inspection of Balance of Plant (Feedwater

'y  System) in accordance with TI 2515/83 " Balance of Plant Trial Inspection Program".

Results: No items of concern were identifie !PJ2oa8&s!Buyp G _ _ . _ . . . . .

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DETAILS Persons Contacted Commonwealth Edison Company (CECO)

 *K. L. Graesser, General Manager Power-Division
 *T. J. Maiman, Vice President Power Operations
 * J. Plim1, Station Manager R. N. Cascarano, Tech Staff Supervisor M. L. Carnahan, Operations Engineer
 *J. E. Ballard, QC Supervisor
 *R. S. Budowle, Assistant Superintendent Technical Service C. J. Simon, Mod Coordinator
 *J. Brandes, Training
 *S. Yuen, Technical Staff D. Kaley, Operating Procedure Coordinator
 *W. Stone, QA Superintendent
 *P. C. LeBlond, Licensing Administrator M. F. Pietraszewski, Section Engineer
 *F. G. Lentine, Power Licensing Supervisor R. E. Lane, Power Engineering
 *C. J. Schultz, Regulatory Assurance Supervisor
 * R. Kurth, Assistant Superintendent - Operation
 *R. C. Johnson, Assistant Superintendent - Maintenance
 *K. J. Hansing, Staff Assistant
 *P. Beinecke, Thermal Group Lead E. J. Campbell, IM Master Mechanic
 *F. G. Lentine, Power Licensing Supervisor S. E. Petrowski, Maintenance Engineer
 *J. Gilmore, Assistant Superintendent Work Planning R. Rafter, PM Coordinator F. Stecha, Planning Department L. Pruett, Senior Operating Engineer B. Radmann, Maintenance Planner K. Depper Schmidt, Master Electrician
 *R. Flessner, Power Operations Staff
 *R. Squires, Nuclear Safety
 * Denotes those attending the exit interview on October 23, 198 The inspectors also contacted and interviewed other licensee employee . Inspection of the Feedwater System in Accordance with TI 2515/83 General The purpose of this effort was to implement a limited trial inspection program on a " Balance of Plant" (B0P) system that has been shown to contribute significantly to challenges of safety

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systems and overall risk from a probabilistic risk assessment (PRA) perspective.

l The Feedwater System was chosen as the focus of this inspection l because it was the single system most responsible for unplanned reactor trips from above 15% power during 1984 and 1985. This system also has been a significant contributor to plant risk in many plant's PRAs. The importance of increased attention to the B0P side of the plant was emphasized to the industry in the 1985 loss of feedwater event at the Davis-Besse facilit This inspection was not intended to be compliance oriented but rather to provide an overview of the licensee's BOP related programs and to assess the effectiveness of those programs. The licensee's attention to any concerns or weaknesses identified during this inspection has the potential for increasing B0P systems reliability and hence decreasing challenges to safety systems. An aggressive, safety conscious approach to the management of a nuclear facility will not be limited solely to the safety related systems but will apply a reasonable effort to those areas of the plant which present potential safety system challenge A review of plant operating history, maintenance history and interviews with plant personnel were used to identify those components of the feedwater system having a history of unreliability or that have caused or complicated recovery from plant trips and transients. As a result of this review it was decided that this inspection would focus on (though not limited to) the following items: Feedwater pump turbine control system failure Feedwater pump (motor driven) discharge valve failure Feedwater pump recirculation line vibration Feedwater pump 2c (General) The intent of the inspection was to review the licensee's overall performance with regard to the above, specifically addressing the programmatic areas of maintenance, design, modifications, management , support, and operations. In an effort to perform a more thorough i assessment of the licensee's performance in each of these programmatic areas, the inspection team felt it necessary in some cases to expand the scope of the inspection beyond the four items listed above, Design and Modification Aspects The NRC inspector performed an evaluation of the licensee's overall l programmatic approach to processing design modifications. This i evaluation included the licensee's followup investigations and activities related to long-term corrective actions with regard to  ; design modification l l l l

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Specific problem areas associated with the feedwater regulating valves (FRVs), Main Feedwater (MFW) pump turbine controls and the 2C MFW pump were reviewed. A general review of all Balance of Plant (B0P) modifications made during the last two refueling outages for each , unit was performed in addition to the proposed B0P modifications for l the next refueling outage on Unit 1. The NRC inspector also looked at specific modifications related to the Instrument Air (IA) system and the main turbine control system. During the course of the evaluation, the NRC inspector reviewed design modification packages, deviation reports (DVRs), licensee event reports (LERs), piping and instrumentation drawings and the Zion Action Item Activities Repor P modifications have been an ongoing program for as long as the plant has been operating. The recent operating history reflects the attention given to the B0P in that MFW related trips have essentially been eliminated in the past few years. One of the major contributors to the MFW system problems in the past was related to difficulty in controlling feed flow through the FRVs during startup. To prevent or alleviate this problem a feedwater bypass automatic control system was installed to provide automatic steam generator level control while operating on the feedwater bypass valves. Other problems related to the FRVs, such as diaphragm failures, were corrected without any design change Many design changes have been performed over the life of the plant related to the turbine-driven MFW pumps, the most significant of which is the "Lovejoy" modifications made to the turbine control system. Because of recurring MFW pump trips related to the turbine control system, modifications were performed in 1980 to install a completely new turbine control system that was manufactured by the Lovejoy Controls Corporation. These modifications replaced the then existing governor valve positioners, governor, and control system block with the Lovejoy 200 series syste The Lovejoy dynamic counter-balanced 200 series system consists of a governor and steam valve servomotors, current-to-pressure transducers, a pneumatic positioning bellows, a manual regulating valve, a speed limit relief valve, a signal processor and an instrument panel which provides system performance indication. The operation of the 200-series system is relatively simple. High pressure oil from the turbine oil pump is fed through a selection valve which directs flow through one of two identical control flowpaths, A and Each flowpath consists of a filter-orifice module, a speed changer valve, and a flowpath isolation valve. The oil takes a pressure drop across the filter-orifice and another pressure drop across the speed changer valve, the position of which is determined by the turbine controller signal. The resulting pressure is fed to both the governor and the steam valve servomotors. The governor is a mechanical-hydraulic device which holds a speed selected when the controller output is constant. A signal processor was included which essentially provides a feedback loop to stabilize the overall control and prevent huntin _ _ _ _ - _ _ _ _ _ _ - _ _ _ - _ _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - _

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In 1981, the Lovejoy system was upgraded on MFW pump 2C in an attempt to further increase the reliability of the speed control system. This 1981 change replaced the speed-changer valves (needle type valve) with a drain-type (dump) valve and eliminated the governor. A "deadband" module was added to the signal processor to reduce servomotor induced oscillations. Also a provision was made for manual air control to allow bypassing the signal processor and the manual / automatic (M/A) station to permit work on those components without taking the MFW pump 3 off the lin j During the most recent refueling outage for each unit these same changes were made to all of the MFW pump control systems. Also during the last refueling outage, additional modifications were made to install a track and hold system and provide redundant power feed As a result of this most recent modification, the demand signal generated by the MFW pump control system is sent to a microprocessor based control system which is powered by independent and redundant power supplies. The track and hold system is designed to lock in the speed demand that was present prior to a loss of the speed demand signal, thus preventing an unnecessary trip. These Lovejoy modifications have mainly been responsible for the increased reliability of the MFW pump During the review of the plant DVRs issued over the last few years, it was noted that the 2C MFW pump appeared to be a more prominent contributor to plant trips than other recurring MFW system problem The NRC inspector, therefore, reviewed these DVRs to determine if the licensee's actions adequately addressed the root causes and where necessary that adequate design changes were made. There were four DVRs associated with the 2C MFW pump between 1981 and 198 The root cause for each of these DVRs was independent of one another with no recurring failures. Of these root causes, only one (22-2-82-71) was associated with a deficiency that resulted in a design change. The , DVR resulted when the 2C MFW pump tripped on overspeed for no apparent  ! reason. The overspeed was determined to be caused by failure of a l electro-pneumatic transducer, Model T-25, manufactured by ITT Hammel Dahl Conoflow. The licensee's followup noted that previously the same type transducer, on a different pump, had failed from excessive vibration due to its mounting location. The licensee, therefore, replaced the transducer with a different type / manufacturer on all the turbine driven pumps. The licensee's decision to change out the transducers on all the pumps at both units shows a conscientious effort to address root causes and to apply necessary design changes to components on a timely basis rather than wait for a failur The licensee uses the same design change control and documentation l system for all facility modifications. Safety-related and B0P

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modifications go through the same programmatic approach. The documentation system assures a proper followup from all disciplines when a design change is approved. This process assures that the design changes are reflected in the plant procedures, texts, training, and drawings and ensures that the completed modification is approved

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l-I . Another significant B0P modification related to the maih turbine control system was performed in 1984. This consisted of replacing ' the MS 24 and 25 Hagan transmitters with more reliable Rosemount transmi tters . The Rosemount transmitters are powered from redundant safety-grade power supplies with adequate isolation between the safety and nonsafety-related portions. This modification vastly improved the reliability of the EHC system which is a known contributor to unnecessary turbine / plant trips at all power plant The NRC inspector also reviewed the design and modifications to the Instrument Air (IA) system. At Zion, the DVRs and LERs did not indicate that problems with the air system resulted in any reactor trips, however, problems with oil and moisture, and compressor / dryer reliability were indicated. The oil problem was caused by the continued need to cross-connect the IA system with the Service Air (SA) system. To resolve this problem the oil in the SA system was eliminated by some design changes. To alleviate the moisture problem, individual traps / strainers were installed at the inlet to critical components. These individual traps were added because the dryers could not maintain the dewpoint below the specified desig Other modifications have been made to improve reliability which include: added capacity, addition of an absorbent cartridge in the IA line, installation of various IA isolation valves, addition of an IA vent valve and associated piping, providing hour meters on the IA compressors and installation of in-line air filters to the compressor loading solenoids. A major modification is underway / planned to replace one of the reciprocating type compressors and the associated air filter assembly with a screw type compressor and a more efficient air drye Assuming good results from this one compressor / filter assembly, all of the present IA compressors / filters will be replaced. The amount of work performed on the IA system even though the system did not contribute significantly to plant down time is a good indicator of the licensee's attention to B0P systems in genera Although the NRC inspector did not note any weaknesses in the licensee's program in general, there were a few instances where the followup of specific items were not specifically addressed. One of these involved problems with the motor-driven pump discharge valve. The licensee noted recent problems with this valve in that the valve occasionally holds its position and will not re.spond to position demand, and if the valve does respond to the position demand, the position is not always equal to the given demand. Although design changes are being contemplated that will alleviate this condition, a review of DVR 2-83-118 indicated this problem may have existed for some time. The licensee's followup to this event indicated that the lock up valve on the actuator was at fault and that the operators were aware of previous problems associated with the discharge valves not immediately responding to a demand signal. Since this was noted as a recurring problem, further investigation may have been warrante Another case involved a loose potentiometer on the local 2C MFW pump controls. The licensee's closecut of this item noted that a preventive maintenance procedure revision may be appropriat . _ _ _ _ _ _ _ _ _ _ _ _ _ - _

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However, no further documentation was included in the DVR package to indicate if such a revision was made or was determined to be inappropriat A third case of questionable followup involved a proposed modification to the IA system. A January 1984 proposed modification to install individual filters at critical components was cancelled in July of 1985. The reason for the cancellation given was that the l reviewer / evaluator felt that the root cause of the problem (moisture) l was not being addressed and the proposed modifi ation was merely

removing the symptoms. However, it was not apptrent that vigorous

, followup was performed in this regard. The NRC .nspector did note that l the individual filters were installed via work requests when it was determined the solution to the root cause was not going to occur in the near future. It was also noted that modifications are still underway to eliminate the root cause by installing a new compressor and dryer unit on a trial basis, i The above examples indicate that more attention might be given to documenting followup of the root causes identified in DVRs such that l any recommendations made are adequately addressed. However, in no way do they indicate a breakdown in the system. In general, the follow-up and root cause determination have been excellent as witnessed by the results of the modifications already performe The operating and maintenance history of the Zion units show a continuous interest and focus of BOP systems in general. During the past two refueling outages between 15 and 20 percent of the total design modifications performed were related to the B0P. The major MFW system changes that occurred as a result of this attention are: removed the thrust bearing trip, raised the MFW pump oil pump auto start pressure, automatic MFW regulation bypass valves installed, removed nuclear instrument system input to bypass valves, replaced the MFW pump control system, modified inverter power supplies to the control system and substantially increased preventive maintenance on MFW components, such as the FRV Between 1980-1984 there were 24 reactor trips that were related to the MFW system. From 1984 to present there have been no reactor trips related to MFW system , malfunctions and for over a year there have been no trips at either ' uni The design aspect of various MFW system modifications was reviewed for general engineering approach and implementatio Although all of the reviewed modifications were classified as non-safety related, several modifications required seismic qualifications due to Category II over Category I consideration Because of this, additional controls were required during the design and implementation phases of the modification Recent changes in CECO's design and modifications process have affected safety-related as well as nonsafety-related projects in { significant ways. The outcome of these changes should be a design change package with fewer field changes and installation difficultie i l 7 1

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One of the more basic changes made to the modification process is  ; the requirement for every modification to have an associated project plan. Previously, only safety-related modifications were required to have project plans. The weakness in the old system was that if a project was incorrectly classified as being nonsafety-related, , there was no independent verification that it was indeed nonsafety-l related. By requiring every modification to have a project plan, ' the safety designation will be reviewed from a technical, managerial and quality assurance point of vie The other significant change that was made for nonsafety-related modifications concerned seismically qualified components. Under the new program any modification involving seismic calculations will be controlled by the corporate engineering department. Previously,. only safety-related modifications had to be controlled by corporate > engineering and the tech staff at the station could control nonsafety-related modifications. This new requirement will result in nonsafety-related seismic modifications being treated the same as safety-related modification The post installation dimensional verifications will assure that the seismic qualification is not invalidated due to field change Modification No. 1-84-29: Upgrade feedwater pump controls and replace electronic This modification was nonsafety-related; however, portions of the work required components to be seismically qualified. This modification was part of the continuing process of upgrading the feedwater control syste Based on the modification documentation, it would appear that the original design work had not been completely pre-engineered. There were a number of scope changes and Engineering Change Notices (ECNs) indicating that during the implementation process unforeseen conditions were found. An example of this was the design change that added a run of conduit to the modification. The reason for the change was that the existing cable trays did not have sufficient capacity to accommodate the new wiring. This is something that would have been expected to be determined during the pre-engineering stage as opposed to the implementation stag Although this modification was nonsafety-related, a 10 CFR 50.59 safety evaluation was performed. Neither the FSAR nor the Technical Specification were affected by the modification. However, the safety evaluation adequately addressed the increase in probability of an occurrence, the possibility of a different type of accident and the decrease of the margin of safety. None of the above questions were affirmativ As previously noted, major design changes were implemented using the ECN process. Smaller field discrepancies and as-built deviations were all handled under the Field Change Request (FCR) process. Both of these methods assured that any design change received adequate ,

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I review and approva In this respect, this modification was handled ' the same as a safety-related modification. By utilizing these processes, the design integrity of the seismically qualified components could be adequately verifie Modification No. 1-84-61: Transmitter change out for pressure transmitters MS-24 and MS-2 This was a nonsafety-related modification that requested seismic qualification for the transmitter mountings. Although no calculations were available for review on site, the mounting details were designed by Sargent and Lundy and were presumed to be properly analyze This was a relatively simple modification entailing the replacement of the existing transmitters with new more reliable ones. In addition, individual power supplies were needed for each new transmitter. Based on the documentation, it appears that the requirement for new fuse holders associated with the power supplies had been overlooked during the pre-engineering process. These were fabricated and installed by field personne Although the need for a safety evaluation was reviewed as part of the modification documentation, the justifications given did not appear to address the real issues. The basis for all three aspects of the safety evaluation was the fact that the modification was not safety related. This justification does not address the fact that l the modification required seismic qualification of the transmitter

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and power supply mountings. Although these evaluations were considered adequate, this was a potential weakness in the evaluation Design changes that were encountered during this modification were resolved using " Speed Memos" from Field Engineering to the Statio (It should be noted that this practice is no longer allowed under the new modification process.) This permitted changes to the design drawings to be made by use of the Drawing Change Request (DCR) process as opposed to the ECN and FCR process. The potential weakness in this approach was that field changes, which could conceivably affect the seismic qualification of a component, would not require an engineering review. Some of the dimensional discrepancies resolved by this method pertained to the mounting details of the transmitters. Although a competent engineer

  " evaluated" these discrepancies, he was not involved in the original seismic qualification and therefore was not certain that even small dimensional deviations would affect the calculation During the documentation review, it was noted by the NRC inspector  l that the mounting dimension for the attachment steel had mistakenly  l been noted as 2'-2 3/4" on Drawing M-499 sheet 238. This dimension  1 should have been l'-2 3/4", as stated in the original ECN. This discrepancy was not detected through three revisions to the drawing or the post installation verification process. Although there is

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no safety significance associated with this discrepancy, it does indicate a potential weakness in the amount of detail that was applied to nonsafety-related modification > Modification No. 1-82-104: Feedwater recirculation line-supports and pipin Feedwater recirculation line vibration has been a long standing ! problem at the Zion Station. This problem has not necessarily ' impacted operations, but has been significant enough to warrant four different modifications in nine years.

' Initially, the modifications only addressed the symptoms of the i' proble After noting an excessive amount of vibration on these recirculation lines, additional supports were added to stiffen the line and reduce the overall motion. This approach was used for the first three modifications with limited success. Although the lines were moving less, the vibration was still ther The most recent modification, however, finally appears to focus on i the root cause of the problem. Instead of trying to resupport the lines, engineering analyses were perfonned to determine what is causing the line to vibrate. The recent analyses indicate that the problem is apparently due to flow induced vibration from extremely high fluid velocities. Recommendations were made to modify the pipe size, valve internals and orifice for the recirculation line To date only a portion of this work has been accomplished with limited success in reducing the vibratio Additional modifications are anticipated-in the future to finally resolve the recirculation line vibrations. Based on discussion with the responsible engineers, actual operational data will be collected and used to reduce the amount of uncertainty in the previous engineering analyses. Prior to this, all of the design work was performed using unconformable assumptions. Based on these refined analyses a final determination will be made as to the most efficient solution to this long standing proble The recent modification work appears to have been well organized. No { significant field problems were evident which indicates that the work was adequately pre-engineered. All of the design changes that did occur were resolved using the ECN and FCR processes. This assured that any noted field discrepancies would be reviewed by engineering and would not invalidate any previous design assumption j During the field inspection of various modified supports, it was noted by the NRC inspector that the as-built configuration of hanger M-1FWRH-1432R was incorrect. The drawing did not indicate the j presence of an additional pipe hanger which is supported from the ) auxiliary steel of this hange Based on conversations with the responsible engineer, no record could be found to indicate that this additional load was accounted for in the design of the new suppor For this specific instance, the NRC inspector judged that the

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omission of-this load was not a safety concern. However, this could be a significant weakness in the balance of plant design process if actual field configurations are not accurately analyzed.

l ! Conclusions The overall design process for B0P modifications is generally very well implemente For the most part, modifications are adequately pre-engineered. The only weakness that was evident during this inspection was the level of detail paid to the as-built configuration of the modification. In two instances, the as-built configuration was not noted which could potentially affect the bases for the engineering evaluations. This weakness, however, should be corrected as a result of the recent changes made to the overall modification process. The level of detail paid to the field configuration prior to, during and after any modification has been increased significantly with the new process. This area should be monitored in the future to verify that this weakness is correcte In general, it was determined that the licensee has paid adequate attention to the 80P systems in the way of design and design modifications. The strong points associated with the licensee's programmatic approach to design . changes include but are not limited to the following: The treatment of B0P and safety-related modifications is basically the same and the same documentation process is use Generally when problems arise that appear to be generic in naturc, followup to include all similar components at both units is goo The overall documentation process is very good in that it results in feedback to procedures, training and testin It also ensures revisions to design documents and approval by Quality Control and Quality Assuranc Safety and nonsafety-related interfaces appear to be routinely recognized and adequately dealt wit All disciplines are involved by signature which should result in adequate control and revie As a result of the inspection, the NRC inspector concluded that the licensee's process for design modification requests and approvals is excellent and has been instrumental in the recent operating history of the Zion unit Operations

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System Valve Lineups The NRC inspector reviewed Condensate and Feedwater valve lineups performed by the licensee by walking down the Condensate and Feedwater system and spot-checking various valves. The valve lineup sheets were found to be more comprehensive than the P& ids in that valves which were not found on the P& ids were listed on the valve lineup sheets. Valve lineups at the Zion Station are controlled by Zion General Operating Procedure GOP-0. This procedure documents and identifies all the prerequisites associated with a reactor startup. Checklist

    "D" of GOP-0 outlines the requirements for performing system valve lineups. With the exception of safety system valve lineups which are required to be performed after a refueling outage, the responsibility of identifying BOP system valve lineups is assigned to the Operating Engineer. Although GOP-0 does not require periodic B0P valve lineups to be performed, the NRC inspector noted that valve lineups on the Condensate and Feedwater systems were performed recentl Walkdown The NRC inspector performed a walkdown of the Unit 1 Feedwater and Condensate systems using the P& ids to check for the following:
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Labeling of valve Proper valve position Valve / pump general condition The NRC inspector spot checked valves in the major flowpath to verify that they were in the correct position in accordance with the specified valve lineups. No major discrepancies were foun Valves inspected included: 1PDS-CD-121, CD-122, CD-123, CD-124 IPI-CD-13, CD-15, CD-17, CD-19 1PDS-CD-125, CD-126 CD-127, CD-128 It should be noted that instrument root valves do not appear on the P& id For example, IPI-123 as well as three other pressure indicating instruments which appeared to provide suction pressure of the condensate pumps, were not shown on the P& ids. Also, the NRC inspector found that 10D0-215 and 217 were shown capped on the P&lD but were found to be not capped in the field. Conversely, valves 1C00-211, 212 and 213 were shown not capped on the P&ID but were fuund to be capped in the field. The inspector did find the general material condition of the Feedwater and Condensate systems to be good and that the licensee appeared to be stressing general housekeeping. Although the NRC inspector identified some oil and condensate leaks, most of these discrepancies were already identified by the licensee. Oil leaks from the Condensate and Feedwater systems appeared to be manageable, although at the time of the inspection an oil leak on the 1B condensate pump thrust bearing had brought the oil level to the add mar Additionally, most valves were found to be labele _ _ _ _ - _ _ -

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Operator Information The NRC inspector verified that the licensee has a program to disseminate industry generated information as well as NRC Bulletins and Information Notices. The licensee informs operators and other key personnel through their required reading program. This required reading program was found to be comprehensive and appeared to be very effectiv The required reading package is published by the training department and incorporates such items as: Changes to procedure Changes to technical specification Significant events at other plant Instrument setpoint change * Selected NRC Bulletins, Circulars, and Information Notice Recent Zion DVRs and LER This required reading package is distributed to key Zion personnel such as all licensed personnel, all non-licensed operators and all training staff members. The licensee ensures that the responsible personnel performs the required reading by removing their site access badges if not completed by the required date. Also, plant modifications are routed to the training department so that they can be incorporated into training as require Conclusions Valve lineups are controlled by procedure and are the responsibility of the Operating Engineer. Valve lineups appear to be adequately controlled based on the NRC inspector's walkdown. Valves were generally found labeled and equipment condition good. The required reading program appears to be effective in passing information to operating personnel. Information pertaining to changes in system operation due to plant modifications appears to be effectively disseminate Maintenance The NRC Inspector reviewed the content and the extent of the licensee's condensate and feedwater maintenance program. Although the preventive maintenance performed on the Condensate and Feedwater systems appeared to only stress pumps and remote operated valves, the NRC inspector concluded that the program was adequate in light of Zion's successful operating histor The NRC inspector reviewed the general surveillance program computer data base in order to identify the types of surveillance which were in the program. It appeared that the licensee did not perform periodic maintenance on their check valves in the Condensate and Feedwater system. It also appeared that motor and turbine preventative maintenance was not being performe Although the licensee has had few problems because of this lack of preventative maintenance, it appeared to the NRC inspector that such preventative maintenance

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items should be considered because of plant age. Additionally, it was noted that the general surveillance computer data base contained errors. These errors consisted of not performing same of the PMs on similar equipment. For example,1A,1B,and IC condensate pumps have a PM to check their pump seals, but 1D condensate pump does no Furthermore, the NRC inspector learned through interviews that because of the large maintenance backlog, PMs in the past have taken a lower priority than corrective maintenance. Although corrective maintenance is required to be performed, the HRC inspector was concerned that due to the time constraints and pressure for startup, PMs may be ignored and not performe The inspector reviewed the CECO Total Job Management (TJM) Progra This progrEn was developed for the purpose of accomplishing effective and efficient maintenance work and providing enhanced documentatio This program was reviewed with specific attention being given to its application to the Feedwater system at Zion. The program achieves its goals through management of available resources and by addressing such factors as communication, cooperation, planning and organizing, and control. The " vehicle" which is used to accomplish this in the maintenance program is the Work Request Form. Zion Administrative Procedure 3-51-1, Revision 9, describes the use of this form in initiating, logging and routing work requests at the Zion Statio This form is used for Feedwater system work as well as other B0P and safety-related system work. The station has also taken the initiative to heighten the corporate guidelines so that all production work is under this same review and approval proces The process includes full control, from initiation of work through performance, to completion and review. Major aspects of the process include quality control reviews, numerous management approvals, formulation of work packages, which contain procedural instructions of varying detail, listings of part availabilities, maintenance histories and computer tracking capabilit This work control process and the TJM program at Zion appear to be well unrferstood and utilized at all levels of management within the Maintenance Department and among the technical staff. Its continued use, with some improvement by addition of more detailed work procedures is a positive step in increasing reliability in not only the B0P systems, but throughout the entire statio Maintenance activities related to a few specific items were reviewed by the NRC inspector in an effort to assess overall effectivenes I Several feedwater regulating valve diaphragm ruptures resulted in plant trips and deratings. A Deviation Report written in the 1983 timeframe resulted in the discovery of a shelf-life problem with rubber diaphragms. A check of storeroom records showed that the failed diaphragms were 8-10 years old. A policy was instituted to require all rubber diaphragms more than five years old to be disca rded. In addition, as a preventative maintenance measure, feedwater regulating valve diaphragms in service were to be changed out every refueling outage. Due to the successful operation of the diaphragms in recent years, the PM interval has been adjusted to require change out of the diaphragms every second refueling outag _ _ _ _ - _ _ _ __

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l The feedwater pump control system regulates pump speed on the turbine driven pumps and controls discharge valve position on the motor driven pumps. The function of this controller is to maintain a programmed delta P across the feedwater regulation valves which in turn optimizes the throttling characteristics of the valv Early plant operating history shows recurring reactor trips resulting from malfunctions of this control system. The mechanical ' fly-ball governor portion of the system was especially troublesom Records indicate that for the period 1974 through 1979 the feedwater control system accounted for approximately 50% of the total plant trips and deratings. During this period, the Zion Station experienced a total of 20 reactor trips due to control system problem A new feedwater pump turbine control system was installed in the 1979 timeframe and has since been modified in 1981 and again in 1987. The modifications as previously discussed, included an upgraded hydraulic system, microprocessor controls, elimination of the mechanical governor, redundant power feed, and addition of a track and hold syste As a result of the control system modifications, reactor trips attributed to this system were reduced to three during the period 1980-1984 and zero from 1985 to present. The Feedwater system overall was responsible for 24 reactor trips in the period 1980-198 In summary, the licensee's aggressive attention to this potential challenge to safety systems has effectively been all but eliminate The discharge valve associated with the motor driven feedwater pump is used to regulate flow to maintain a programmed delta P across the regulation valves. A review of the maintenance history shows repetitive failure of this valve to respond to control signal The primary causes of these failures have been traced to lock-up relay actuation and valve position false indication as previously discusse The lock-up relay's function is to lock the discharge valve in position in the event of a loss of air supply to the valve actuato Examination of the lock-up relay following failure of the valve to respond to a control signal has found the relay diaphragm failed on several occasions. Failure of this diaphragm on at least one occas, ion has resulted in a reactor trip due to the inability of the discharge valve to open. As a result of the diaphragm failure history, the technical staff is currently considering the use of an alternate diaphragm material or installation of a redundant lock-up relay. Additionally, replacement of the lock-up relay is being added to the station's PM progra Numerous failures of the valve positioner to valve stem feedback mechanism has resulted in a loss of valve position control. The current cable and spring feedback link has been responsible for the erratic valve position control. This problem is currently

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i being resolved by replacing the positioner with that of an improved desig Maintenance history of the feedwater pump turbines shows a , recurring problem regarding pump speed stability when operating on ' low pressure steam. In this mode of operation, a rack of sequential poppet valves control steam admission to the turbine. After numerous attempts tc troubleshoot the control instrumentation, a system test was developed by the station to determine the source of the instability. Results of the testing determined that the poppet valves are not lifting to provide a linear speed increase. Poppet valve lift points were adjusted based on the test results and have resulted in an increase in linearity and stability of turbine spee Maintenance planning and administrative controls are used to minimize adverse safety consequences of concurrent or sequential maintenance, testing, and operating activities. The primary responsibility for plant safety when maintenance and testing activities are in progress is given to the Operating Departmen The Unit Operating Engineer (0E) reviews all incoming work requests (WR) and is responsible for assuring that the Technical Specification references are correct, and that the proposed activity will not conflict with current plant condition In addition, the Shift Engineer (SE), Shift Foreman (SF), or Shift Control Room Engineer (SCRE), who are licensed senior reactor operators (SR0s), must authorize each WR before work in the plant may begin. Additional reviews are performed when equipment is taken out of service (005), or when jumpers, lifted leads, blocks, and bypasses are used to prever.t conflicting work from causing a reduction in safety. These administrative controls apply equally to safety-related and B0P equipment, except that safety related jumpers, lifted leads, blocks, and bypasses receive On-site Revie Two planning meetings take place each day. At 6:45 a.m., representatives from each maintenance shop, operating department, technical staff, and planning department meet to discuss the maintenance and testing activities for the day. The operating department can then become aware of which WRs will present conflicts with each other, with testing, or with plant condition At 8:00 a.m. each shop is again represented at the plant morning meeting, which included management personnel from all plant areas up to the Plant Manager. Each department's daily priority jobs ace again reviewed, and potential conflicts are resolved. During refueling cutages, outage meetings are also conducted at 2:30 each day. These meetings are attended by the OE in addition to all maintenance department Each week, the Total Job Management (TJM) meeting is held to discuss future major work prioritie The licensee is currently increasing the capability of the Planning Department in an effort to make more effective use of plant resources. There have been recent transfers from mechanical maintenance and operating departments, and an additional transfer

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from the ALARA group is planned. The planning group already includes TJM staff and the PM planner The strength of these planning and administrative controls is that the most key operating (0E, SE, SF) and planning department individuals have a great deal of experience at the statio Consequently, plant performance with respect to events caused by conflicting maintenance activities is generally acceptabl Some weaknesses were noted: Any SR0 on shift may authorize a WR. Some WRs are authorized by a SF and others, which may affect control board indications or controls, are authorized by the SCRE. An informal means (making a photocopy of WRs) is used by some shifts to alert the SCRE that the SF or SE authorized a job to start. However, the potential still exists for one SR0 authorizing work on a job which may conflict with a WR approved by another SR Although the meetings discussed above take place daily, there appears to be no program which describes their content, attendance, and purpose. The meetings have actually been evolving at the station in the last few years, and their effectiveness has resulted in improved communications and planning. It may be beneficial, at some future point, to formalize certain aspects of the meetir.g Some maintenance procedures (typically EM and MM) may be improved by including plant or system conditions, in addition to other cautions which may be applicable. The MM department uses " job sheets," which, for each plant component, provides some information of this type, but job sheets do not appear to have any controls on them, other than what the person inputting information desires to writ Conclusions In general, the maintenance effort at Zion appears to be effectiv The formalized PM program, while relatively new, appears to be headed in the right direction. A potential er.hancement to the PM effort would be to dedicate a couple of full time personnel to accomplish the actual PM program work. The overall Work Request system appears to be effective at Zion, this includes the 80P requests (treated as identical to that of safety-related requests).

For the most part, it appears that repetitive maintenance problems are addressed and adequately dealt with. Maintenance planning and administrative controls are effectively used to minimize adverse consequences of concurrent or sequential maintenance, testing and operating activities. The lack of formalized guidelines for the post maintenance testing of equipment is a potential weakness in the maintenance program. The possibility of a lack of operating personnel coordination with respect to authorizing WRs is a p;tential programmatic weakness. Restrictive plant or system conditions should be included in the maintenance procedure, as applicabl f _ _ _ _ - _ _ _ _ _ _ _

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. Management Support The number of B0P.related or BOP complicated reactor trips has been viewed as one indication of the amount of management support provided to 80P systems. A review of the records at Zion shows that these trips have been reduced significantly since 1980 and is being maintained at a very low number. Since 1982, only seven trips were caused by feedwater equipment. The last feedwater related trip was in May 1986, and was due to operator erro Management has shown, and is continuing to show, involvement in B0P problems, recognizing the significant impact that B0P systems can have on reactor plant operation Management has demonstrated the desire to continue improvement in operation by initiating or upgrading many programs and addressing potential problems that have been identified. Actions taken irclude:

Implementation of the " reliability related" program (Zion Administrative Procedures (ZAP) 3-51-1A), which is to ensure reliability and emphasize quality control in systems other than " safety-related" or " regulatory related" which includes B0P systems. An in-house assessment is to periodically be accomplished to review complianc Formulation and activities of the Trip Reduction Committee (ZAP 2-54-4), to accomplish reduction and elimination of trips from any sourc Utilization and expansion of the Nuclear Tracking System and other computer programs, which include B0P related informatio Implementation of the Total Job Management Program. This program specifies the work control process for all production work on all systems to ensure reliabTIIty and quality of work for plant equipment. Corporate guidelines , are exceeded at Zion to provide additional manacement 1 l review and control. Procedures used in non-safety related systems are not yet as detailed as safety-related system work instructions, but progress is being made in this are Emphasis on performance of root cause analysis for identified problems so that adequate corrective actions can be taken. At least four different groups or sections have been identified as having a responsibility for performing root cause analysis. These include the Trip Reduction Committee, the Reliability-Related Committee under the Technical Staff Supervisor, the Regulatory Assurance l

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Office (by designating investigation responsibility), and the Maintenance Department. These analyses will have to be carefully managed to produce meaningful results, that can be

 .used with certainty, to take appropriate action rather than conflicting, inconsistent results that can be confusing or misleadin Management has been responsive to B0P problems; a review of commitments made to IE Bulletins, Information Notices and NRC inspections indicated that these concerns are addressed and not ignored or back-shelve Management is participating in a number of industry initiatives ,

that address B0P problems. These include the Westinghouse Owner's ' Group - Trip Reduction and Assessment Program, INPO, and the independent Scram Frequency Reduction Committe Allocation of resources made available to B0P systems was reviewe Many major modifications of the BOP had been made. These included modification of the feedwater regulating valve controls, feedwater bypass valve modifications, and simulator training changes that recognize potential feedwater conditions. It appears that fund allocation is not based upon which system the allocations are involved with, but rather upon job merit and justification as relating to total plant operation. Based on existing problems, current programs, and recent operating history, allocations appear adequat Conclusions The attitudes of management at Zion toward the BOP systems generally appear to be well understood and implemented at all levels of management and at the worker level. It appears the size of the technical staff is not so large that the staff cannot work closely together, and furthermore, it appears that staff personnel work well together. This working relationship may be a contributing factor for why Zion is able to maintain satisfactory plant operation with few reactor trips, and yet still continues to seek ways of improving plant reliability and operations, Summary This inspection, while limited in scope, included the timeframe l start-up through the present. The Inspection Team observed a steady evolution of Zion's BOP awarenes Though many of the same activities were accomplished in the past without formalized programs, the increased corporate attention to the B0P side of the plant has resulted in both a more efficient and safer facilit Zion's 80P programs have evolved from occasional input from the corporate Reliability and Design Engineering Group, the early

 " reliability related" treatment of select B0P equipment within the i
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Related Program. Portions of the proposed corporate Conduct of Maintenance Directive, including the formalized application of root cause analysis was reviewed and is believed to be a very positive step. By formalizing programs related to the B0P and utilizing industry inputs such as INP0, a heightened awareness and increased performance of B0P equipment can be expected. Programs both in place and proposed served to bring the problem areas to the attention of management sooner and to flush out some of the more subtl The indicators which were observed during this inspection led the Inspection Team to conclude that while there are areas where improvement is possible, the general trend in Zion's treatment of the 80P is very positiv . Exit Interview The inspectors met with the licensee representatives (denoted in Paragraph 1) at the conclusion of the inspection on October 23, 198 The inspector summarized the purpose and findings of the inspectio The licensee representatives acknowledged this information. The inspector also discussed the likely informational content of the inspection report with regards to documents of processes reviewed during the inspection. The licensee representatives did not identify any such documents / processes as proprietar _ - __-_ _ ___ __ _______ __. }}