IR 05000373/1987017

Insp Repts 50-373/87-17 & 50-374/87-17 on 870505-14. Violations Noted:Number of Breakers Listed in Tech Spec Table 3.8.3.2-1 Had Not Received Insp & Corrective Maint as Required by Tech Spec Paragraph 3.a

ML20214T229
Person / Time
Site:	LaSalle
Issue date:	06/03/1987
From:	Falevits Z, Gardner R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20214T169	List: IR 05000373/1987017 ML20214T166 ML20214T207
References
50-373-87-17, 50-374-87-17, NUDOCS 8706100170
Download: ML20214T229 (9)

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U. S. NUCLEAR REGULATORY COMMISSION

REGION III

Reports No. 50-373/87017(DRS); 50-374/87017(DRS)

Docket Nos. 50-373; 50-374 Licenses No. NPF-11; No. NPF-18 Licensee: Commonwealth Edison Company P. O. Box 767 Chicago, IL 60690 Facility Name: LaSalle County Station, Units 1 and 2 Inspection At: LaSalle Site, Marseilles, Illinois Inspection Conducted: M y 5-14, 1987

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Inspector: Z. Falevits I'!? 7 Date

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k . Approved By: R. N. Gardner b 3 Plant Systems Section Date Inspection Summary Inspection on May 5-14, 1987 (Reports No. 50-373/87017(DRS); 50-374/87017(DRS))

Areas Inspected: Routine, announced safety inspection of licensee action on previous inspection findings; review of drywell temperature program; training; and Licensee Event Report (LER) review and followup (92700, 92701, 92702 and 41700).

Results: Of the four areas inspected, one violation was identified (a number ,

of breakers listed in T.S. Table 3.8.3.2-1 had not received the inspection and I corrective maintenance as required by the T.S.-Paragraph 3.a).

I B706100170 870603 PDR G ADOCK 05000373 ppg .

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DETAILS 1. Persons Contacted G. J. Diederich, Station Manager

+*R. Bishop, Station Superintendent

• R. W. Stobert, Station QA Superintendent

• J. C. Renwick, Production Superintendent

• D. A. Brown, QA Superintendent

+*T. A. Hammerich, Technical Staff Supervisor

• E. Sheldon, Assistant Superintendent Maintenance

+*G. L. Morey, EMD

+*D. A. Spancer, Technical Staff Engineer

. C. Witenberg, Technical Staff Engineer

• T. W. Wiemholt, Technical Staff Sargent & Lundy Engineers

• J. S. Easterman, Electrical Project Engineer NRC

• J. Jorden, Senior Resident Inspector

• Kopriva, Resident Inspector The inspector also contacted and interviewed other licensee personnel during this inspectio * Denotes personnel attending the May 7, 1987, exit intervie * Denotes personnel participating in the May 14, 1987, telephone exit intervie . Licensee Action on Previous Inspection Items (Closed) Open Items (373/85013-01(DRS); 374/85013-01(DRS)): This item concerned lack of administrative controls to prevent inadvertent use of certain HFA relay coils in safety related applications. Work Requests Nos. L23972, L28559 and L35295 were subsequently implemented to upgrade safety related spare relays with ' Century Series' type HFA relays. This item is considered close (Closed) Violation (373/85013-03(DRS); 374/85013-03(DRS)): This violation relates to an inspector's concern that the licensee's individual who performed the replacement of safety related HFA relay coils also performed the required QC inspection on the same coil The licensee stated that the 100% QC_ inspection and verification of the installed coils were documented on traveler A-LS-1 by the-QC inspector's signature. The licensee noted that this QC inspector was, in all cases, different from the individual who performed the relay replacement. Based on licensee's response this item is considered close l

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. (Closed) Unresolved Items (373/86030-01(DRS); 374/86030-01(DRS)):

During the inspection conducted in July,1986, the inspector identified numerous deficiencies in the licensees implementation of the program to control temporary system changes such as electrical jumpers, and lifed leads, as delineated in Station Procedure LAP-240-6, Revision 11. Subsequently, the licensee completely revised the procedure and issued Revision 12, on August 26, 1986. The inspector reviewed the revised procedure which appeared to be adequate. This item is closed.

, (Closed) Open Item (373/87010-01(DRS)): During maintenance activities conducted on Standby Liquid Control Squib valve 2C41-F004B, the licensee had identified that Cable No. 25C023, feeding the Squib valve, contained blisters on the outer surface of the cable jacke This was a Rockbestos, two pair No.16, 600V Cable. The licensee sent

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a section of the cable to Rockbestos for analysis. In a letter from the Rockbestos company to Sargent & Lundy Engineers, dated April 15, 1987, the vendor stated that the apparent blistering on the jacket appear to have been caused by the escape of vapor from the cable core; that the most likely vapors are residual solvents from the paint on the single conductors. The analysis concluded that this condition should not affect the environmental qualification of the cabl Based on this conclusion, this item is close . Licensee Event Report (LER) Review and Followup The inspector performed an onsite followup inspection of LER No. 373/87-013 associated with a Unit 1 high drywell temperature event. This inspection was conducted to determine if the root cause of the event was adequately identified; that the corrective action taken was adequate, and if appropriate actions had been taken regarding any identified generic issue On March 12, 1987, with Unit 1 in operational Condition 1, increases in several reactor parameters including drywell temperatures and pressure were observed by the licensee. Initial investigation revealed that the "B" Return Air Fan motor primary breaker was closed but the motor ammeter read zero amperes; also, the Primary Containment penetration breaker for the "B" fan had tripped. No indication of the ,

trip was available to control room personnel since the breaker logic '

did not contain indication logic circuitry. Due to the failure of the Primary Containment Return Air Fan Motor, temperatures in the drywell reached 180 F for more than four hours. In addition, SRVs, B, D, J, P, and V were exposed to temperatures above 180 F for a duration of less than four hours. The high temperatures encountered, which were determined to be above the calculated Trigger and Alert points set by the temperature monitoring procedure, contributed to a reduction of the remaining qualified life of the SRVs.

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The licensee determined the apparent cause of the event to be high vibration on the "B" supply fan which was caused by the motor drive bearing failure. The high vibration caused the electrical lead feeding the motor to wear through and expose the conductor. This caused a short to ground and the backup feed breaker to trip. The inspector noted that breaker trip indication was not available to the control room operator due to the designed circuitry. Although the Primary Containment ventilation fan is classified as non safety, it is designed to maintain the ambient air temperature in the containment to maintain the qualified life of safety related equipment. In addition, it serves to maintain the bulk average drywell temperature within the bounds of the initial design criteria used for the analysis of the peak Loss Of Coolant Accident (LOCA)

pressure and temperature conditions. The inspector noted that during this event the primary breaker failed to trip as required due to mechanical binding of the tripping linkage. This binding was apparently caused by a lack of preventative maintenanc In addition, the fan differential pressure switch which initiates a control room alarm and provides a trip signal to the primary breaker of the loss of fan flow also faile Review of licensee corrective action indicated that licensee actions included, (1) replacement of the inboard and outboard fan motor bearings and blades, (2) repair of the motor lead, (3) performance of motor electrical megger and bridge resistance check (4) replacement of differential pressure switch and repair of damaged sensing lines, (5) lubrication and cleaning of the primary breaker, (6) inspection of "A" Primary Containment ventilation fan for bearing failure or signs of excessive vibration, (7) an analysis performed on equipment located in the drywell which indicated no significant effects on remaining qualified life, (8) preventive maintenance on metal clad circuit breakers now being performed per LES-GH-105 on a five year frequency as required by Technical Specification 4.8.3.2.b and (9) training of all licensed Operating Department personnel to be conducted regarding this even The inspector expressed the concern that during this event numerous components failed to function as designe Technical Specification 4.8.3.2.b entitled, " Primary Containment Penetration Conductor Protective Devices" required under surveillance that at least once per 60 months, each circuit breaker be subjected to an inspection and preventive maintenance in accordance with procedures prepared in conjunction with its manufacturer's recommendations. Documented evidence was not available for review to indicate, prior to its failure to trip, when the required inspection and preventive maintenance was performed on the Primary Containment Vent Supply Fan 18 circuit breaker. During this inspection the licensee could not provide the inspector with documented evidence that 17 additional 480V molded case circuit breakers, denoted in

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Table 3.8.3.2-1.d, had received the required inspection and preventive maintenance in the last 60 months. Subsequently, the licensee infonned the inspector that inspection and preventative maintenance on 12 of the 17 primary breakers was completed during the outage in 1986. The licensee's Technical Staff engineer agreed with the inspector that the backup breakers which were not specifically denoted in Technical Specification Table 3.8.3.2-1.d should have been because they act as backup to the primary breaker protection. The backup breakers were put in service during the last outage and were tested during the installation period; however, during this inspection, evidence was not available for review documenting the performance of inspection and preventative maintenance on these breakers which are the backup protection to the primary ones delineated in Technical Specification 4.8.3. Subsequent to the end of this inspection, licensee investigation indicated that breakers on bus 136y-2 had been inspected but that the documentation had been misfiled and recently found; that during installation of the breakers, the electrical contractor's procedure as well as the OAD test procedure contained statements which require personnel to check for breaker damage. The licensee also submitted a sampling of test documentation and investigation results pertaining to the Technical Specification breakers. The licensee, however, did not submit a specific date and a related inspection or surveillance number indicating that each of the primary and backup breakers which were not inspected to the requirements of Procedure LES-GM-109, had received a comparable inspection in the past assuring operability. In addition, the licensee indicated that five breakers denoted in Technical Specification Table 3.8.3.2-1.d as items c), d), 1), j) and w) had not received the required inspection and preventative maintenance as required by Technical Specification 3.8.3.2. The five breakers mentioned above had been installed prior to Unit 1 entering Mode 2 of operation (in 1982) at which time all surveillance requirements had to be met as stated in Technical Specification 4.0.1. However, no records were available to show that this surveillance (3.8.3.2) was ever met for the five breakers in question. Furthermore, the five backup breakers not denoted in the Technical Specification but electrically connected in series to the five Technical Specification primary breakers had also not been inspected since they were installed (approx. 1980).

The inspector noted that records associated with inspection and preventive maintenance of safety related electrical breakers were not organized in a central location, neither were they controlled by a specific individual or group familiar with this activity. Many of the records could not be located during or after the inspectio Based on the above findings, the inspectors informed the licensee that failure to adhere to Technical Specifications 3.8.3.2 and 4. requirements is a violation (373/87017-01(DRS)). )

The inspector conducted a review of LaSalle Procedure LES-GM-109, Revision 0, dated September 29, 1983, entitled, " Inspection of 480V Klockner-Moeller Motor Control Center Breaker," and compared its

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contents and requirements with applicable Klockner-Moeller Vendor Instruction Manual No. AWA-USA-123-378 (3/76). The inspector noted the following differences between the two documents:

Corresponding Vendor Pa; agraph N Paragraph N B.1 Examine case and covers of (1) (Examine case . . . . ).

breaker for cracking and However, if there is any bubblino. The clear cover question contact the Vendor may b;come darkened as a and DO NOT use the circuit result of normal switching, breake particularly in the arc chute area. This is normal and will not hinder circuit breaker operatio D.1 Operate breaker to the ON and (5) The circuit breaker should 0FF position to ensure proper be turned ON and 0FF several operatio times. If the circuit breaker is equipped with a shunt or undervoltage trip accessory, operate the accessory several time No requirement note (6) For verification of overcurrent tripping characteristics consult Klockner-Muller for methods, test currents, and trip times which are applicabl In addition, the vendor instruction noted that it is not unusual for a circuit breaker to be in service for extended periods and never be called upon to carry out its tripping functions; therefore, the circuit breaker should be periodically checked as noted under the

" Maintenance" sections. Furthermore, vendor instructions AWA-USA-462-25 (3/75) stated that periodic maintenance of bus bars and incoming cable connectors should be performed annually or more frequently depending on service condition and established maintenance policy. Discussions with licensee maintenance personnel, and review of applicable procedures indicated that this has not been accomplished. The inspector noted that preventive maintenance activities appear to lack coordination and administrative control. Pending additional review this item is consideredopen(373/87017-02(DRS);374/87017-01(DRS)). Paragraph c of LER-87013 stated that the Primary Containment Penetration backup breaker for the "B" fan, which had tripped during ,

i the event on a ground fault, was sized at a " considerably higher

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amperage than.the primary breaker so as to allow a trip only upon failure of the primary." During this event the primary breaker failed to trip due to binding of the tripping linkage. This binding was apparently caused by a lack of lubrication and preventive maintenance on the breaker. In addition, while the primary breaker had position status lights located in the control room, the backup breaker had not contained circuitry to provide control room indication that the fan had tripped. The licensee indicated that this particular circuit is unique; that other penetration protection circuits contain control room indication for both primary and backup breaker In addition, IEEE 308-1980, entitled, " Standard Criteria for Class 1E Power Systems for Nuclear Power Generating Stations," states in Section 5.13 that, " failure of any circuit penetrating containment shall not result in exceeding the maximum current versus time capability of the containment penetration for that circuit during any design basis event requiring isolation." The inspector expressed the concern that due to the high current passing through the penetration conductors during this event, the current might have exceeded the maximum current versus time capability of the containment penetration for this circuit. No pertinent data was available for review during this inspection. Items discussed in b above are considered open pending additional revie (373/87017-03(DRS); 374/87017-02(DRS)).

N c. The inspector questioned the licensee as to the past inspection and preventive maintenance activities relative to the remaining 6.9KV, 4.16KV and 480V safety-related circuit breakers which are not part of Technical Specifications but are part of safety related ECCS system The licensee presented the inspector with Procedure LES-GM-118, Revision 1, dated February 27, 1986, entitled, " Inspection of Ak-2 and Ak-2A circuit breakers." Attachment B of the procedure listed the location of the G.E AK-2 circuit breakers as follows: 250VDC MCC 121Y and 221Y; 250VDC bus No. 1 and 2; 125VDC AA, 18, 2A and 28; switchgears 135X, 135Y, 235X, 235Y, 136X, 136Y, 236X and 236Y. The licensee stated that during the present outage on Unit 2, inspections and preventive maintenance activities are being conducted on the Unit 2 safety-related AK-2A breakers; however, as of the date of this inspection only three out of 44 Unit 1 breakers had been completed to the requirements of Procedure LES-GM-118. (Note: Unit 1 has been in operation since April, 1982). Furthermore, the inspector noted that LaSalle Units 1 and 2 are equipped with additional safety-related electrical breakers which were manufactured by several different manufacturers. Due to lack of inspection time the inspector could not verify the licensee's inspection and preventative maintenance program applicable to these safety related breakers. Pending further review by the inspector this item is considered unresolved (373/87017-04(DRS);

374/87017-03(DRS)).

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The inspector witnessed an inspection and preventative maintenance activity in progress. Licensee maintenance ersonnel using

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Procedure LRS-GM-105, Revision 3, entitled, p' Inspection of 480V (600 AMP) Circuit Breakers," performed the requirements of the above procedure on the breaker located in 480V switchgear 233B, cubicle 401C, which serves the Radwaste Exhaust Fan O The maintenance personnel appeared to be knowledgeable of the task being performe . Review of the Drywell Temperature Program The inspector conducted an inspection to review the licensee's program to monitor, document, report, and evaluate high drywell temperatures. This

review included a field inspection and observation of temperature data monitored by two recorders located in the Unit 1 Reactor Building; temperatures monitored by Control Room CM recorders, and Technical Specification related temperatures taken each shift through the use of toggle switches in the Control Room. In addition, the inspector reviewed temperature data collected weekly using Attachments A and B of drywell

temperature Station Procedure LTP-300-17 issued to govern drywell temperature data collected, and provide followup when high temperatures i

exist. Routine performance of activities controlled by this procedure are scheduled as part of the station general surveillance program. The procedure included temperature trigger set points and guidelines for accelerated data gathering when higher than normal temperatures are

, encountered. The procedure also included a mechanism for formal-transmittal of temperature data to the engineering department for evaluation and approval of changes to the acceptance criteria. It also specified required notifications and engineering evaluations to be performed if E.Q. limits are exceede The inspector's review of the collected data indicated that readings taken by Unit 1 thermocouple 1TE-VP211, located at elevation 746' 0" at MSIV D6 (metal temperature) have exceeded the E.Q. trigger setpoint of 150 F throughout most of the period reviewed. This data has been transmitted to engineering on a monthly basis for evaluation of remaining qualified life of the affected safety related components. Unit 2 drywell temperatures collected have not exceeded the trigger setpoints during the period reviewed. Latest SNED to LaSalle Unit 1 drywell temperature data for sensor 1TE-VP211 recorded for the month of March, 1987, concluded that the MSIV NAMC0 EA-740 limit switches and Seal Assemblies have remaining qualified life of 1.31 and 1.37 years, respectively, from March 14, 1987, at a temperature of 170 F; that the consumed life for the period of March 15-31, 1987, is 11.5 days for both devices. Thus the remaining life of the limit switches, and Seal Assemblies, (using the Arrhenius methodology),is1.28and1.34gearsfromApril1,1987,'providedthe temperature does not exceed 170 Also, the ASCO solenoids will not need replacement prior to the next fuel cycle provided the temperature at 1TE-VP211 does not exceed 190* The licensee has been monitoring sensor 1TE-VP211 on a daily basis; the data collected is transmitted on a monthiy basis to engineering for evaluation. The inspector also reviewed the following associated documents:

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• SNED letters dated March 13, and April 1 and 14, 198 * S&L letters dated March 13, March 26, and May 1, 198 * Quarterly Drywell Temperature Summary for the period from January 1, to March 31, 198 * Work Requests WR Nos. L46579 and L4658 * Unit 1, Control Room Logs No. 100, dated March 12 and 13, 198 * Unit 1, Shift Engineer Log No. 124, dated March 13, 198 Licensee implementation of the drywell temperature program was found to be in accordance with the procedure and appeared to be adequate in maintaining the drywell temperatures to within the remaining qualified life of safety related component . Training The effectiveness of the licensee's training program was reviewed by the inspector during the witnessing of the licensee's performance of maintenance activities. Personnel appeared to be knowledgeable of the task being performe . Open Item Open items are matters which have been discussed with the licensee, which will be reviewed further by the inspector, and which involve some action on the part of the NRC or licensee or bot Open items disclosed during this inspection are discussed in Paragraphs 3a and . Unresolved Items An unresolved item is a matter about which more information is required in order to ascertain whether it is an acceptable item, an open item, a deviation, or a violation. An unresolved item disclosed during this inspection is discussed in Paragraph 3 . Exit Interview The Region III inspector met with licensee representatives (denoted under Paragraph 1) at the conclusion of the inspection on May 7 and conducted a final exit during a telephone conference on May 14, 1987. The inspector summarized the purpose and findings of the inspection. The licensee acknowledged this information. The inspector also discussed the likely informational content of the inspection report with regard to documents or process reviewed by the inspector during the inspection. The licensee did not identify any such documents or processes as proprietar