ML20150C312
| ML20150C312 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 06/30/1988 |
| From: | Caldwell J, Cantrell F, King L NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML20150C304 | List: |
| References | |
| 50-338-88-16, 50-339-88-16, IEIN-87-041, IEIN-87-41, NUDOCS 8807120429 | |
| Download: ML20150C312 (10) | |
See also: IR 05000338/1988016
Text
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UNITED STATES [[~ ' ' - ' - NUCLEAR RECULATORY COMMISSION '
, REGir% 11 ._ f , , _A ' cg' ij. 101 MARIETT/. STREET, N.W. /1!
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Report Nos.: .50-338/88-16-and 50-339/88-16 -3 < , . [ Licensee: Virginia Electric ~and. Power Company - Richmond,.VA- 23261 ' s ' Docket'Nos.: 50-338 and 50-339 License Nos.: NPF-4 and NPF-7 Facility Name: -North Anna 1 and 2 e Inspection Conducted: May 14 June 10, 1988 ' -Inspectors: [- lb b b> h' J. L. Caidwell,_Sen or Reside 6t Inspector Date Signed Okk ZDX% v &ai- G L. P. King, Residdnt In ecy Date Signed - Approved by: E [l, F. Ca5trell, Section Chi ~0at6 Signed
Division of Reactor Pro cs SUMMARY Scope: This rcutine inspection by the resident inspectors involved the following areas: plant status, review of inspector fol. lou-up items, monthly _ maintenance observation, -monthly surveillance observation, ESF walkdown, .and operator : safety verification. During' the performance of this inspection, the reside. t inspectors conducted reviews of the licensee's backshift operati'ns on the following days - May 15, 19, 24, 26, June 1, 2, 3, 7, 8, 9 and 10. Results: Two violations were identified: (1) failure to perform an adequat'e 10 CFR 50.59 safety- evaluation before placing the Recirculation Spray Heat Exchangers.(RSHXs) in wet layup conditions --paragraph 4; and, (2) violation of TS 3.8.1.1 for having two inoperable Emergency Diesel Generators (EDG) paragraph 8. o G807120429 880630 PDR ADOCK 05000338 0 PDC ( . - . _; _
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s . I<.i.- .- - 1 REPORT DETAILS - , k . > 1.' _ Licensee' Employees Contacted- - G.~E. Kane, Station Manager . ~ *R.LC..Driscoll, Quality Control (QC) Manager 4 .
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0.' Enfinger, Assistant' Station Manager '
- M. L. Bowling, Assistant Station Manager
- J. A. Stal!, Superintendent, Operations
'*M. R. Kansler, Superintendent, Maintenance
- A. H. Stafford, Superintendent, Health Physics
- D. A. Haacock, Superi tendent, Technical Services-(Acting)
J. L. Downs, Superintendent, Administrative Services - J.;R. Hayes, Operations Coordinator E. S. Hendrixson,~ Engineering Supervisor-(Acting) 0. E.. Thomas, Mechanica) Maintenance. Supervisor- .g . P G. D. Gordon,' Electrical Supervisor L. N.1Hartz, Instrument Supervisor F. T. Terminella,.QA Supervisor J. P. Smith, Superintendent, Engineering ' D. B. Roth, Nuclear Specialis+.
- J. H.-Leberstein,-Engineer
- T.-L. Po"ter, NSE Supervisor
- 0. E. Quartz, Associate Engineer
Other licensee employees contacted include technicians, op_rators, mechanics, security force' members, and. office personnel .
- Attended exit interv'iew
2. Exit' Interview-(30703)' 'The inspection scope and findings were summarized on June 10,.1988, with those persons indicated in . paragraph 1 - above. The' licensee acknowledged the incpectors findings'. The licensee did not identify as proprietary any: of the material provided to or reviewed by the i nspectors .during this inspection, c (0 pen) Violation- 338,339/88-16-01: Failure to perform an adequate 10 CFR 50.59 safety evaluation potentially resulting in all of the RSHXs 1 being "inoperable" due to fouling of the heat transfer surface resulting from wet layup conditions paragraph 4. (0 pen) Violation 338,339/88-16-02: Violation of TS 3.8.1.1 for having 2H and 2J EDGs ir. operable at the same time for approximately 38 hours. This rest ited from an inadequate avaluation of an INP0 SER 14-87 and IEIN 87-41 paragraph 8. , a w , . , _ e - 4 . - - - - - - -
( , g ,- - n , y . .- . , - 2 p p z, . , 3. Plant Status x ' . Unit'l < Vnit 1 Lbegan and ended the inspection period operating' at approximately. 100% power. Unit.2 Unit'2 began the. inspection period operating at_approximately 100% power. On May 19,.the licensee discovered that both the 2J and 2H Emergency Diesel: Generators (EDG) had been inoperable for.approximately 38 hours. y At the time of discovery, the. 2J EDG, which.-had been inoperable due to. ' preplanned preventative maintenance, had just-completed the surveillance test and was fully ' operable (see Section '8 for details). .The unit. continued to. operate at approximately 100% power throughout the inspection g period. ' Both Units.
On June 18, a meeting ~ was conducted in Atlanta with .the' licensee concerning the 'recent discovery of the heat transfer problems ' associated with both - Units 1 and 2 RSHXs. The meeting concluded. with' the NRC satisfied that the actions already performed and the ones committed-to be performed by the licensee were sufficient _to permit _ continued operation of both Units 1 and 2. ~ y, , 4. Review of.. Inspector Follow-up Items (92701) (0 pen) ~ URI 338,339/88-11-02: Potential Inoperable. Recirculation Spray Heat Exchangers. l A review was conducted by the inspectors of 1-PT-210.1 . and 2-PT-21011 "Valve Inseivice Inspection (Service Water MOVs to:RSHX)". l The inspectors reviewed the microfilm of the procedures back to 1985. - The procedures had been deviated to allo- the heat exchangers to _ remain full of. water af ter' the surveillance test ntrary to the commitments ' of the. 'UFSAR. which r. equi. red then drained and oiown dry with air. The inspectors
- could not find any completed 10 CFR 50.59 safety evaluations that. allowed
deviation of the procedure until October 1987 when a 10 CFR 50.59 safety evaluation'was performed'to allow the deviation-to PT-210.1. This safety evaluation was inadequate in that it did not address .the fouling of the ' heat exchangers as a potential problem. The licensee later provided the inspectors with a safety evaluation performed in 1980 which allowed the heat exchangers to be filled with . primary grade water following the heat exchanger draining sequences. This safety evaluation also did not address the heat transfer capability reduction due to increased fouling from the heat exchanger being wet < instead of dry. In May 1988, following the partial CDA signal on Unit 2, (as discussed in Inspection Report 338,339/88-11, Section 10) which resulted in service " t
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' . ,, .. l. .- .- . . 3 o waterf flowing through the .RSHXs, the inspectors requested a copy of the . licensee's .10 CFR 50.59 safety evaluation to allow. deviation from the-FSAR commi.tments to maintain the RSHXs in dry layup. This safety evaluation concluded' that the previous evaluations had been inadequate;because .they - did not address the decrease in heat transfer capability due to the increase fouling from the heat 'exchangers being exposec' to service water. The May 1988, safety es aluation .also determined that the design fouling. factor for the RSHXs was 'zero- and .that based on the Tubular Exchanger Manufacturers Association (TEMA) manual the fouling factor was actually approximately 0.002 for the type of service water at North Anna. With this fouling factor, the licensee determined that the ' service water temperature could not exceed 84 degrees F and still have the heat transfer capability of the RSHXs comply with the design basis in that containment pressure would not necessarily be subatmospheric within an hour following a design based Lo:s of Coolant Accident (LOCA). An investigation of previous service water temperature records indicates that it is not uncommon for service wa' 2r temperatures to exceed 84 degrees F during the , hot summer months. , 10 CFR 50.59 states in part that 4 licensee may make changes in. the procedures as described in the safety analysis report without prior Commission approval unless the proposed change involves a change in the TSs incorporated in the license or an unreviewed safety question. A . proposed change shall be deemed to involve an unreviewed safety question if the margin of safety as defined in the basis for a TS is reduced. Final Safety Analysis Report (FSAR), paragraph .6.2.2.2.5 states in part that in order to ensure long-term reliability of the recirculation spray heat exchangsrs, following each periodic test of the heat exchanger inlet and outlet valves (e.g. PT 210.1), the heat exchangers .are put in dry layup by draining water through the beat exchanger drain valves and' then purging the heat exchanger with compressed air until there is no visual indication of moisture f rom the drains. TS 3.6.2.2 states in part that the containment recirculation spray system shall be operable with four separate and independent containment recirculation spray subsystems, each composed of a spray pump, associated heat exchanger and flow path. The failure of the licensee to perform an adequate 10 CFR 50.59 evaluatior when periodic tests 1-PT-210.1 and 2-PT-210.1 were deviated to allcw the l' heat exchangers to remain filled with service water constitutes a violation and is identified as violation 338,339/83-16-01. l - The licensee has flowed each of the heat exchangers with service water and has completed a special procedure involving the heat exchangers being '
injected with chemicals tr remove any biological fouling. The heat exchangers have been flushed, drained and blown down with service air. t The licensee power. engineering service, has written a letter to plant i ! engineering stating that once the recirculation spray heat exchangers are l placed in dry layup and the surveillance program is established to ensure they remain in dry layup, a service water temperature administrative limit l of 92 degrees F. is applicable based on a Jry fouling factor of .00075. p l L
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, ,. .. .' . .. . . 4 < ' The licensee informed the inspector that based on. chemical analffis of- - RSHX's ; flush water, the visual inspection of the RSHX, and calculation by their contractor, they will revise their previous' evaluation of the worst case fouling ' factor and the maximum allowed service water temperature. This item . will remain' open pending the inspector's review of the reanalysis. , . 5. Monthly Maintenance (62703) - Station mainte ince activities affecting safety related systems and components were observed / reviewed, to ascertain that the activities were conducted in accordance with approved procedures, regulatory guides and industry codes or standards, and in conformance with Technical Specifications. No violations or deviations were identified. 6. Monthly Surveillance (61726) .The inspectors observed / reviewed technic 11 specification required testing and verified that testing was performed in accordance with adequate procedures, that test instrumentation was calibrated, that limiting conditions for operation (LCO) were met and that any deficiencies identified were properly reviewed and resolved. The inspectors reviewed portions of 2-PT-213.1 for the in-service inspection of containment isolation valves. The following valves failed to indicate shut: 2-TV-SS-206B (Hot Leg Sampin Valve) 2-TV-SS-212B (Steam Generator, Surface Sample) 2-TV-SS-20SA (RHR Sample Header Inside Containment) 2-TV-SS-200B (Pressurizer Liquid Space) In all cases, the action required by TS 3.6.3.1 was taken. The other valve in the line was closed and de-energized and a work request was -written to perform necessary corrective action on the valve. The licensee will be evaluating the operation and maintenance of these valvos to determine the root cause. The inspectors also reviewed 1-PT-24.1, Calormetric. No problems were identified. On May 24, the inspectors witnessed portions of the Unit 2 survaillance test 2-PT-34.3, Turbine Valve Freedom Test. This procedure' verifies that each of the turbine isolation valves will go shut when the auto stop oil is bled off of the valve. This ensures that steam will be isolated to the turbine following a trip signal which bleeds off the auto stop oil pressure, to prevent turbine overspeed. During the test, two of the low pressure turbine isolation valves failed to go shut when the test solenoid was de-energized. The licensee determined that the test solenoid had 1 , w , - - - - 7--
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e ,, , . 5 -stuck in the closed position. The test solenoids were uastuck and the . valves, were successfully stroked. The . inspector was able to determine, based on discussions with the licensee, that the test' solenoid failure has - no affect on the normal flow path for the auto stop oil during.an-actual ~ -overspeed trip ' signal . Ccnsequently, a failure of a test: solenoid will cnot prevent =or hinder an-actual overspeed protection isolation. No violations or deviations were identified. i. 7. ESF System Walkdown (71710) The following selected'ESF systems were verified operable by performing a walkdown of the accessible and essential portions of the systems on June 7, 1988. The inspectors performed a walkdown of Chemical and Volume Contrcl System using 1-0P-8.1A. No violations or deviations were identified. 8. Operational Safety Verification (71707) By observations during the inspection period, the inspectors verified .that the control room manning requirements were being met. In addition, the inspectors observed shif t turnover to verify that continuity of system status was maintained. The inspectors periodically questioned shift personnel relative to their awareness of plant conditions. Through log review and plant tours, tne inspectors verified compliance with seiected Technical Specification (TS) and Limiting Conditions for Operations. In the course of the monthly activities, the resident inspectors included a review of the licensee's physical security program. The perfcrmance of various shif ts of the security force was observed in ~.he conduct of daily activities to include: protected and vital areas . access controls, searching of personnel, packages and vehicles, badge issuance and retrieval, escorting of visitors, patrols and compensatory posta. The inspectors kept informed, on a daily basis, of- overall status of both units and of any significant safety matter related to plant operations. Discussions were held with plant management and various members of tile operations staff on a regular basis. Selected portions of operating logs and data sheets were reviewed daily. The inspectors conducted various plant tours and made frequent visits to the Control Roem. Observations included: witnessing work activities in . progress; verifying the status of operating and standby safety systems and equipment; confirming valve positions, instrument and recorder readings, annuciator alarms, and housekeeping. The following comment was noted: ,
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. 5 i, . ,. t _ (' stu'ck in the closed position. .The ' test solenoids were unstuck and the . v>1ves were successfully stroked. The inspector was able to determine, based on discussiens with the licensee,-that:the test solenoid-failure has "" no affect on the normal flow pa'th for the auto .stop oil during an actual overspee Trip signal . Consequently, a failure of a' test solenoid will - not prevent or hinder an actual overspeedl protection isolation. L ' No violations or ds.viations were identified, 7. ESF System Walkdown (71710) The following selected ESF syr tems were verified operable by performing a walkdown of the accessible > 1d essential portions of the systems on June 7,.1988. The inspector s performed a walkdown of Chemical and Volume Control System using 1-0P-8.1A. No violations or deviations were identified.
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Operational' Safety Verification (71707) By observations during tha inspection period, the inspectors verified that
the control room manning requirements were being net. In' addition, the inspectors observed shift turnover to verify that continuity- of system status was maintained. The inspectors periodically questioned shift personnel relative to their awareness of plant conditions. Through log review and plant tours, 'the inspectors verified compliance . with selected Technical Specification (TS) and Limiting -Conditions 1 for Operations. In the course of the monthly activities, the resident inspectcrs included a review of the licensee's physical security program. The performance of various shifts of the security force was observed in the conduct of. daily activities to include: protected and vital areas access controls, searching of personnel, packages and vehicles, badge. istuance and retrieval, escorting of visitors, patrols and compensatory posts.. The inspectors k'ept informed, on a daily basis, of overall status of both units and of any significant safety matter related to plant operations. ' Discussions were held with plant management and various members of the operations staff on a regular basis. Selected portions of operating-logs and data sheets were reviewed daily. The inspectors conducted various plant tours and made frequent visits to the Control Room. Observations included: witnessing work activities in progress; verifying the status of operating and standby safety systems and equipment; confirming valve positions, instrument and recorder readings, annuciator alarms, and housekeeping. \\
_ . - _ _ _ . _ _ _ _ _ _ _ . - - . - __ _ _ _ _ _ _ _ _ _ _ _ _ _ . _. _ _ _ _ _ _ _ _ _ _ - _ _ _ - _ _ _ _ - _ _ _ - _ _ _ . ' * , . - t . .. .. , 6 , . The fo'llowing comment was'noted:
On May 19, 1988, wFile testing - the 2J Emergency Diesel Generator (EDG) following preventative maintenance (PM), che licensee discovered an oil leak in the governor servo booster and a lagging interference with the governor , linkage. Both ' contributed to the EDG failure to_ operate properly. Consequently, the licensee shutdown the 2J EDG and commenced unplanned corrective maintenance to correct the problems. The maintenance was completed and th)'2J EDG satisfactorily. tested on the same day. - ~ Technical Specification (TS) 3.8.1.1.b requires, with one EDG inoperable, the operable EDG be tested within 24 hours if .the inoperable EDG- is inoperable due. to any cause other than preplanned PM or testing. Since the 2J EDG PM_had changed to unplanned corrective maintenance, then the 2H EDG was required to be tested within 24 hours. On May 19, following the satisfactory testing of the ' 2J EDG, an attempt was made to test the 2H EDG. The attempt was unsuccessful due to a failure of the 2H EDG output breaker to close. The licensee determined that the breaker closing spring. had not been charged due to a failure of the charging motor. The failure . ' of-the charging motor resulted from mounting bolts becoming loose allowing the notor to become unmounted from the breaker frame rendering it unable to charge the' closing spring. The licensee determined that the last time the EDG output breaker had been closed was May 6 and that procedures did s not require the operator to verify the closing spring had recharged. ' Consequentiv, following the breaker manipulation on May .6 the charging motor-failed to recharge the closing spring and the 2H EDG was inoperable until discovered and repaired on May 19. Also, with the PM commencing on > the 2J EDG on May 18, rendering it inoperable, the licensee had both Unit 2 diesels inoperable for approximately 38 hours. The licensee's diesel output breaker is a 4160 vs't breaker manufactured by ITE. This breaker failure and problem associated with the loose mounting bolts was identified in NRC Information Notice Number 87-41 dated August 1987 and INP0 SER '4-87 dated May 1987. However, the Information Notice and SER discussed iailures ass,ciated with Brown Boveri breakers and the licensee has ITE breakers. This resulted in some confusion even though the licensee eventually realized that Brown Boveri had purchased ITE. The INP0 SER 14-87 made the following recommendations: a. Breaker receipt and preventive maintenance inspections should include a tightness check of charging motor mounting bolts. When loose or missing nounting bolts are found during preventive maintenance inspections, the interval between inspections should be decreased, and the creaker should be tested to verify operability. b. Plants with Brown Boveri Type HK circuit breakers that find loose charging motor mounting bolts should consider the use of a thread adhesive and consult with Brown Boveri to determine torquing requirements for the bolts. If thread adhesive is to be used, the manufacturer recommends Loc-Tite number 242 or equivalent. c. Operations personnel daily rounds should include a check of charging motor mechanical indicators where available on safety-related
__ _ _ _ _ _ _ _ - _ _ - . ' W. , , -. . ~ , . . 7 breakers. lhese indicators should also be checked following scheduled maintenance or testing. The_ licensee ' informed the inspectors that their response to the INP0 SER ' ' - involved an undocumented visual inspection of approximately ten non-safety related and four safety related.4160v AC. breakers. This visual inspection as reported to the inspectors did not identify any problems with the charging motors. However, no wrenches were actually placed on the charging motor mounting bolts to verify tightness. Also, the licensee informed the inspectors that they felt that the present .PM procedure EMP-P-PH-01, Electrical Checkout of 4160 Volt Load Center Air Circuit- . Breaker, had sufficient instructions to verify the tightness of the- charging motor mourting bolts. The inspectors review of EMP-P-PH-01 revealed that the only step that would perform this check was step 7.7 1 which simply states "check mechanical tigh; ness of breaker". This step would not require a technician to specifically check the tightness of the charging motor mounting bolts. Recommendation "C" of the INPO SER was not addressed at all by the licensee. Implementation of.this recommendation would have prevented the 24 EDG from being inoperable for several weeks without the licensee's knowledge. A requirement to check that the closing springs were charged following each operation or a requirement to eneck that the breakers are charged on the daily rounds would have identified the inoperable 2H EDG output breaker on May 6. This would have prevented the licensee from operating Unit 2 at 100% power for 38 hours on May 18 - and 19 with two inoperable EDGs. The licensee's response to Information Notice 87-41 ranged from not applicable to North Anna, to, verify if North Anna's ITE breakers are the same as Brown Boveri breakers. However, the only action that was taken was -to contact Brown Boveri. This discussion with Brown Boveri is documer.ted by memo from K. S. Berger, VEPC0, to F. C. Prince, VEPCO, both of the corporate office, dated January 4, 1988. The memo states that Mr. Roland Wintenberger of Brown Boveri (BB) informed tte licensee that no potentially defective breakers have been supplied to North Anna. There- fore, the memo concluded that the Information Notice was not applicable to North Anna. The licensee also informed the inspectors that BB stated that these breakers art good for 1000 cycles and none of the licensee's safety related breakers are close to 1000 cycles. Based on the above paragraph, it is clear that the licensee's response to the INP0 SER and NRC Informa- tion Notice was not adequate to address the problem. Following the 2H EDG output breaker f ailure, all the emergency 4160 volt breakers for both units were verified tn be charged. The licensee is presently developing a program for future surveillances and inspections of the breakers including checking for tightness of the charging motor mounting bolts. The licensee is presently in the process of inspecting as many 4160 volt AC breakers as allowed with the units operations. Of the 137 total safety \\
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-- .: .,: L 3 ., '~ . e. . + v . 4 8' ~ L 'and non-sa'nty related breakers, 22 have been inspected and fourlhave'been identified-with loose mount _ing bolts. . One of the .four defective . breakers c " had one.'of the.three mounting, bolts:which.no' longer'made thread engagement- with.the. breaker frame. A second bolt'.was . loose but the charging motor T > .was 'still firmly. mounted'. witn the third bolt. This -breaker was ... - ~ associated with the Unit 1A low head safety. injection pump. _ ' L T.S. 3.8.1.1 states in part as a minimum,1 the .following- AC electrical. power. sources- shall be operable; two separate. and independent -diesel' generators. The failure of-the licensee to takeithe necessary corrective action: to prevent failure .of the .I EDG output' breaker resulting in both' EDGs being inoperable for approximately 38 hours will be identified as:-a , Violation 339/88-16-02. 'No other violations or deviations were identified. . e i 8 . . . . . . _ - - . . _ _ _ . . . - , _ _ . . ~ . . _ . .. .. .- __,, }}