ML20236K098

Responds to NRC 870828 & 1005 Ltrs Re Violations Noted in Insp Repts 50-338/87-24 & 50-339/87-24.Corrective Actions: Radiation Monitor N-16 Installed on Main Steam Header,Health Physics Technicians Received Training & Procedures Reviewed

ML20236K098
Person / Time
Site:	North Anna
Issue date:	11/04/1987
From:	Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
87-640, NUDOCS 8711090097
Download: ML20236K098 (12)

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! u 6- VIRGINIA ELucTurc AND POWER COMPANY Ricnwonn, VIRGINIA 20261 W. L. StriwueT

Vaca Paastonut h etnas OsenATsons November 4, 1987 U. S. Nuclear Regulatory Commission . Serial No.87-640 Attn: Document Control Desk- NAPS /DBR Washington, D.C. 20555 - Docket: Nos. 50-338' '

50-339 License Nos. NPF-4 NPF-7.

Gentlemen:

VIRGINIA ELECTRIC AND POWER CONPANY NORTH ANNA POWER STATION UNITS 1 AND 2 NRC INSPECTION REPORT NOS. 50-338/87-24 AND 50-339/87-24 We have reviewed your letters of August 28, .1987 and October 5,: 1987 which .

referred to the inspection conducted at North Anna between July 15, 1987 and August 14, 1987 and reported in Inspection Report- Nos. ' 50-338/87-24 and 50-339/87-24. The response to the Notices of Violation are addressed in the attachments.

In addition to the corrective actions identified in the attached response to the Notices of Violation, additional actions hN.. been taken as a -result of the Steam Generator Tube Rupture (SGTR) event experier, cad by North Anna Unit 1 on July 15, 1987. These add:tional corrective actions were docum;nted 'in our letter dated -September 15, .987 and include those areas identified in Inspection Report No. 50-338/87-24 and No. 50-339/87-24 as Unresolved or as an

( Inspector Followup Item (IFI). Major corrective actions completed to date include: 1) extensive steam ger.erator inspections, repair and modification to preclude-fatigue failure as' a mechanism for tube rupturec T' development of a.

t comprehensive pr.matj to secondary _ leakage ' surveillance. program which is L performed frequent'y ard utilizes . multiple indications, 3) the Emergency -

{ '~ Operating Procedure.- and timir; usage during the SGTR have been evaluated by INP0 and Westinghouse =nd rev ewed with the Westinghouse Owners Group, and 4) the Emergency Operatin3 Proadures have been revised' to address -IFI 338/87-24-08 ard IFI 338/d7 44 09 -as wel.1 as other enhancements deemed necessary as a result of'the above reviews. All of. these corrective actions have been: reviewed with-the NRC. -Corrective actions _have also been initiated to address the design of the steam jet- air ejector isolation on high radiation 8711090097 871104 PDR ADOCK 05000338 / l 0 PDR ,

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levels (IFI 338/87-24-07), and the evaluation of the loose . parts monitor alarms (IFI 338/87-24-02) was discussed with the NRC at our September 10, 1987 l meeting in Bethesda. Two other issues dealing with verbatim compliance to emergency procedures (URI 338/87-24-04) and the differences between Revision 0 and Revision.1 of the Emergency Operating Procedures -(IFI 338/87-24-05) are open pending additional NRC review. 'The status of our entire corrective action program is being periodically reviewed with our Resident Inspectors.

Further it is our intent to complete all corrective actions in a timely manner.

We have no objection to this inspection report being made_ a. matter of public record. If you have any further_ questions, please contact us.

Very truly yours, 1

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W. L. Stewart

. Attachments cc: U. S. Nuclear Regulatory Commission 101 Marietta Street, N. W.

Suite 2900 Atlanta, Georgia 30323 Mr. J. L. Caldwell NRC Senior Resident Inspector I

North Anna Power Station l

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ATTACHMENT RESPONSE TO THE NOTICE OF VIOLATION REPORTED DURING THE NRC INSPECTION CONDUCTED BETWEEN JULY 15. 1987 AND AUGUST 14. 1987 INSPECTION REPORT NOS. 50-338/87-24 AND 50-339/87-24 NRC COMMEHI During the Nuclear Regulatory Commission (NRC) inspection conducted on July 15 - August 14, 1987, violations of NRC requirements were identified. -In accordance with the " General Statement of Policy and Procedure for NRC Enforcement Actions," 10 CFR Part 2, Appendix C (1987), the violations are listed below: 1 A. Technical Specification 6.8.1 requires written procedures to be established, implemented, and maintained covering the applicable procedures recommended in Appendix "A" of Regulatory Guide 1.33, Revision 2, February 1977.

Regulatory Guide 1.33, Appendix "A", Section 5, requires writttn procedures for Abnormal, Off Normal, or Alarm Conditions.

I The North Anna alarm response procedures " Main Steam Loops IA-B-C Auxiliary Steam Loop High Radiation" and " Main Steam Loops 1A-B-C Auxiliary Steam Loop Radiation Alert" require the control room operator to notify Health Physics when alarms are received.

Contrary to the above, the written procedures were not implemented in j that the control room operator did not notify Health Physics when the ,

above alarms were received on July 15, 1987. '

l This is a Severity Level IV violation (Supplement I).

RESPONSE

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1. ADMISSION OR DENTAL OF THE ALLEGED VIOLATION:

l The violation is correct as stated.

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I l 2. REASON FOR THE VIOLATION:

The North Anna Annunciator Response Procedures for the main steam radiation monitors call for the control room operator to notify Health l Physics. However, at the time the alarms came in, a number of other

y annunciators were being received and the . operations ' shift was tracking-the status of primary plant conditions which were indicative of a rapidly =

evolving transient. Both pressurizer level 'and pressure were decreasing rapidly which required manual actions to isolate letdown, . increase.

charging. rate, swap charging pump suction to RWST, and' initiate a turbine runback. Since conditions were changing so_ rapidly and there was good.

indication of large _ primary to 1 secondary leakage, the .first ' priority.of the operators was to attempt to stabilize the ~ plant. . _Under .these conditions, it was not appropriate nor was there time for additional-sampling and analysis to confirm leak rate and isotopic content by Health.

Physics. -It was after the decision to manually trip the unit was made (i.e., approximately six minutes into the event) that- Health Physics was notified.

3. CORRECTIVE STEPS'WHICH HAVE BEEN TAKEN AND THE RESULTS ACHIEVED:

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l Operators are trained to respond to all alarms.which are received in the l Control Room in accordance with the ' Annunciator Response Procedures.

L When multiple. alarms are received,. the operator 'is trained ' to fully assess all indications and enter the appropriate procedure (s). This requires that the operators take'a series of prioritized actions.

During September, -1987, Westinghouse ' conducted an' Emergency Operating Procedure (EOP) performance review .which included .an assessment 1 of operator usage of the E0Ps during 'the event. In their report,-

Westinghouse stated that "the operator response during the pre-trip' phase of the event was consistent with the operator action model described in the ERG documentation, that being that the operator .would respond to individual alarms as long as a reactor trip has not. occurred. and is not warranted".

l Corrective actions have been implemented to provide a'n earlier indication l~ of primary to secondary leakage. ,This includes'a N-16 radiation monitor =

l which has been installed on the main steam header. Additionally, a new -

periodic surveillance test (PT-46.2) has been written which requires .:

frequent collection of data for the N-16 radiation . monitor, the air i ejector radiation monitor, the steam- generator blowdown monitor,' air =

l- ejector grab samples, and RCS isotopic samples. _ Based on this data,._

leakage rates are calculated, . plotted, - and compared to: specific..

acceptance criter.ia to provide guidance for_' reduction in power or shut down. The alarm setpoints for the. applicable ? radiation- monitorsi are calculated by' PT-46.2.-to allow early ' detection and': provide timely requirements for the operators to either reduce power or shut down. ?As'a-result, Health Physics will be aware of trends fof increasing leakage before the alarm setpoints are expected to'be reached.

Health Physics Technicians have received systems training which-ihcludes-discussion of the various radiation _ release paths. Also, the continuing I

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training program. for Health Physics Technicians addresses this same information on a two year cycle.

4. CORRECTIVE STEPS WHICH WILL BE TAKEN TO AVOID FURTHER VIOLATIONS:

i The Annunciator Alarm Response Procedures for the: mainc steam' radiation :

monitors as well- as the radiation monitors used in PT-46.2 ' to detect -

leakage will be rereviewed4 for adequacy. . They will be. revised as i

required :to ensure the specified operator response is consistent with l PT-46.2 and that' the timing of the' response is . addressed. . - Also,: Standing L Order No. 155, " Unit One (1) . and ; Unit 'Two (2) Primary To : Secondary -

Leakage", will be revised to emphasize the actions required by; operations' when an alarm is received to: include timely notification of Health Physics. Finally, N-16 c radiation monitors usage. will' be c expanded .by .

placing them on each S/G line to enhance'early detection. and surveillance of primary to secondary leakage.

As part of the continuing training cycle, integrated. simulator training will be conducted for Operations and Health Physics:' personnel to-reenforce procedural requirements for making notifications and to enhance communications. In addition, each of the Health ' Physics shifts .will receive orientation on the radiation monitoring instrumentation- and equipment status indications available .in.the ~ control room which would be.

used to assess radioactive releases through each of the~ release-pathways.

The purpose of this training is to facilitate the flow of information between Operations and Health Physics.,

Future ' Health Physics semiannual Emergency Plan drills will include participation by Operations to ' simulate the notification process.

Emergency Plan Implementing Procedure (EP1P) .4.01 '(Radiological Assessment Director Controlling Procedure) is' being' evaluated to enhance the interface between Health Physics and Operations before activation. of the Technical Support Center (TSC). 'l

5. THE DATE WHEN FULL COMPLIANCE WILL BE ACHIEVED:

The Annunciator Response Procedures will be - reviewed ? and revised as-necessary by December 1, 1987. Standing Order No. 155 will be. revised by.-

December 1, 1987. <

The simulator training will . be conducted - as part of continuing training -

cycles starting _ in 1988. The orientation of Health Physics personne1Lon -

control room instrumentation and status-information for each release path -

will-be completed- by-the end of the first. quarter of L1988.-  ;

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The Health Physics semiannual Emergency 'Pl an drills will include Operations participation starting with the next drill scheduled.for the first quarter - of 1988. EPIP 4.01 will be reviewed and revised by January 1, 1988.

Present plans call for additional N-16 radiation monitors to be installed on each steam line for both units and placed. in service by' April'1,1988.

B. Technical Specification 6.5.1.6.c . requires that the : Station 1 Nuclear Safety and Operating Committee (SNSOC) shall be responsible for review of all proposed changes .or modifications to plant systems or equipment that affect nuclear safety. Technical Specification 6.5.1.7.b requires that' l the SNSOC shall . render determinations 11n writing with regard to whether-or .not the above proposed changes or modifications' constitute' an l unreviewed-safety question.

( l Contrary to 'the above, as of July- 18, 1987, the SNSOC had not conducted l required evaluations of two conditions which were abnormal :and' constituted changes to the stean generators in. Unit 1. These conditions requiring evaluation were steam generator secondary side' foreign' objects and plant operation with leaking explosive steam generator tube plugs.

This is a Severity Level IV violation (Supplement 1). .,

1 l RESPONSE

1. ADMISSION OR DENIAL OF THE ALLEGED VIOLATION:

The violation is correct as stated.

2. REASON FOR THE VIOLATION:

l Prior to the Unit I startup from the 1987 refueling outage, . the. steam generator vendor was requested -to perform two safety evaluations to support the return of Unit 1 to service. Tubesheet video' scans of the- a steam generators had identified eighteen leaking explosive- plugs, and '

. visual inspection of the steam generator ' annulus regions had detected foreign objects in each steam- generator. : However,- Station Deviation

' Reports were not written :to document the conditions. Therefore, the-corrective action -(which, in this case, would have - included - the' preparation of safety' evaluations) was not formally -identified and-tracked.

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3. CORRECTIVE STEPS WHICH HAVE BEEN TAKEN'AND THE RESULTS ACHIEVED:

A Station Deviation Report was submitted documenting the lack of. Station i Nuclear and Safety . Operating Committee review. The- steam generator- i vendor has issued revisions to the original safety evaluations to reflect i additional information gathered during the Unit 1 SGTR outage and further j engineering evaluation on leaking explosive plugs. All foreign objects, j which were known to remain in the steam generators when Unit 1 returned j to power, were addressed. Also, the safety evaluation for the leaking. i explosive plugs was reevaluated. As a result' of the reevaluation, the -l steam generator- vendor concluded that no action was required for the j entire duration - of the next Unit 1 operating cycle. Each of 'the -steam generator vendor safety evaluations has been reviewed against the criteria in North Anna Station Administrative Procedure ADM-3.9 - which requires the evaluation to receive Station Nuclear Safety and Operating

l. Committee. review in accordance with the criteria of.10CFR50.59. Prior to j Unit 1-returning to power, Station Nuclear Safety and Operating Committee. d approved the safety evaluations , for~ leaking explosive plugs and ,

unretrieved foreign objects on October 7, 1987 and October 8, 1987- -

respectively.- It was concluded-that no unreviewed safety questions exist :

for the continued operation of Unit 1.

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4. CORRECTIVE STEPS WHICH WILL BE TAKEN TO AVOID FURTHER VIOLATIONS: )

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i A review of station procedures used to control maintenance and inspection ,

activities for steam generators during outages will be reviewed and i revised to add instructions requiring the initiation .of a Station  !

Deviation Report to document any defects or abnormal conditions. Also, l vendor supplied procedures to. be used under the cognizance 'of station  !

Maintenance and Inservice Inspection personnel will be . reviewed each outage to make sure that requirements' exist in the. procedures to document, via a station Deviation Report, defects. or abnormal conditions, j Station Administrative Procedures will be revised- to- include the 1 appropriate review criteria for vendor supplied procedures.

The Daviation Report is reviewed by station management fortreportability considerations as well as identification of corrective actions which would include the need to prepare a written safety evaluation. All l{

safety evaluations are logged to facilitate tracking, including Station 1 Nuclear and Safety- Operating Committee review and approval prior to the 1 unit returning to power.

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5. THE DATE WHEN FULL COMPLIANCE WILL BE ACHIEVED:

i The station steam generator maintenance and inspection procedures will be  :

reviewed and revised as required by December 15, 1987. Station 1 q

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Administrative Procedures will be revised by December, 15, 1987 to require that vendor supplied procedures. address the use or' . station . Deviation Reports.

C. 10 CFR 50 Appendix B XVI, Corrective Action, requires that measures Lbe-  !

established to assure that. conditions adverse to quality,- such as .!

failures, malfunctions, deficiencies, deviations, defective material and' '

equipment, and nonconformances are promptly identified and corrected. In- '

the case of significant conditions adverse to. quality, .e measures.shall.

assure that the cause of. the condition is determinu and corrective-action taken.to. preclude repetition.

Contrary to the above, adequate measures.were.not taken to determine the cause. nor were corrective actions adequate whenJ steam - jet air ejector radiation monitor 1-RM-SV-121 was restored. to service.in that; no functional or calibration test was run prior to. returning the monitor to service following monitor failures on July 13 and 14, 1987..

-This is a Severity Level IV violation (Supplement.I). 1

RESPONSE

1. ADMISSION OR DENIAL OF THE ALLEGED VIOLATION:-

The violation is correct as stated except for the fact that following the second failure of radiation monitor 1-RM-SV-121 at 2238 hours0.0259 days <br />0.622 hours <br />0.0037 weeks <br />8.51559e-4 months <br /> on-July.14, 4 1987 functional testing and calibration were performed before the monitor  !

was returned to service following the SGTR event.

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2. REASON FOR THE VIOLATION:

l On July 13, 1987, radiation nonitor 1-RM-SV-121, failed .offscale low. LThe.

monitor was . declared inoperable, and a work request was . initiated. I Operations personnel concluded that the o source of the problem - was moisture in the monitor lines. After the.. monitor was drained, it begn to indicate onscale. Based on a channel check, which. is a qualitative assessment of channel behavior by observation, the' monitor was declared operable without completing any other . operability- checks. Since there-exists no other independent channel measuring air ejector'activ.ity or a related parameter, there was no comparison that could be_made.to.-judge if-the output from the monitor was in the correct range.:.In addition, since the . unit was returning from an outage, baseline conditions for. reactor coolant 1 system. activity, steam generator' leak tightness, andi air ejector flow rates - had _ net been t:stablished. Because of these considerations, relying on a channel check was- inappropriate as a means to verify operability. ~However, durina the time' period ;when .the air ejector - -

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monitor was inoperable, air ejector exhaust grab samples were collected and analyzed in accordance with T.S. 3.3.3.11. These samples did indicate the presence of small amounts of activity which was generally consistent with the air ejector radiation monitor readings after it was  !

declared operable.

The effects of moisture in the radiation monitor also were not evaluated. )

It is possible that the subsequent failure of the monitor on July 14, j 1987, which resulted from a failed power supply, was ultimately caused by  !

the moisture in the detector, j

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3. CORRECTIVE STEPS WHICH HAVE BEEN TAKEN AND THE RESULTS ACHIEVED:

While the air ejector monitor was out of service, grab samples ac required by Technical Specifications were taken. The quarterly ci,annel functional test was completed on July 18, 1987 and the channel- calibrated on July 19, 1987. The cause of the failure of the monitor on July 14,  !

1987 was identified to be a failed power supply.

A new performance test, 1-PT-46.2, has been written and implemented which requires the recording and tracking of air ejector radiation monitor readings every four hours in order to establish baseline levels and trend data. An Operations Standing Order was also issued which requires grab samples to be taken every four hours versus every twelve hours as specified in the Technical Specifications if the air ejector radiation monitor is out of service. A means to validate the readings of the air ejector monitor readings after returning it to service now exists, since PT-46.2 data is available for comparison to establish confidence that the monitor is responding properly.

4. CORRECTIVE STEPS WHICH WILL BE TAKEN TO AVOID FURTHER VIOLATIONS:

The procedures used to troubleshoot and repair the radiation monitors required to be operable per Technical Specifications will be reviewed to make sure that the appropriate post maintenance surveillance tests are required to be performed .before declaring the monitors operable.

Reliance only on a channel check as a basis to declare a monitor operable will not be permitted for returning any radiation monitors to service-following a failure. Some form of post maintenance surveillance (such as source check, isotopic analysis of grab samples, . functional testing, and/or calibration) will be required based on the failure mode and-corrective maintenance performed. In the case of the air ejector radiation monitor, the readings of the monitor after it is returned to 4

service can be compared to PT-46.2 leakage data as a further check.

An Operations Directive will be prepared to provide guidance for returning inoperable instrument channels to service. The Operations

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o i Shift Supervisor' will verify that post maintenance testing. has been completed before declaring . an instrument channel operable. .The Instrument Department will be required to . complete the appropriate-troubleshooting-and repair prcredures before the instrument- channel will i be returned to service.  ;

The new performance test (2-PT-46.2) will also be . implemented on Unit 2 -

before the unit returns to Mode 1 after its current refueling ' outage.

The Operations Standing Order-applies to both Unit l'and 2.

5. JJLE DATE Wi!FN TULLCGNPLIANCE WILL BE ACHIEVED: . l l

The procedure review will be completed and revisions made to incorporate the appropriate po:t maintenance surveillance requirements for the i radiation monitors aadressed in the Technical Specifications by j December 1, 1987. j The Operations Directive will be implemented by December'1,1987.

D. Technical Specification 4.3.3.11 :tates' that each radioactive Jgaseous effluent -monitoring -. instrumentation channel shall- be- demonstrated operable by performance of a daily channel check, a monthly source check, channel calibration during refueling, and quarterly. channel functional test.

Technical Specification 1.17 states that a system,. subsystem, train, I component, or device shall be operable or have operability l when. it is capable of performing its specified function.

Contrary to the above, daily channel checks and monthly source checks.for-radiation monitor 1-RM-SV-121 were inadequate--in ^ that .dur.ing ' July 1987 the acceptance criterion used for acceptable- radiation ' monitor performance, i.e., free needle movement, was inadequate to' verify that the radiation monitor was capable of performin'g its specified' function or was operable.

This is a Severity Level IV violation (Supplement IV).

RESPONSE

.1. ADNISSION OR DENIAL OF THE ALLEGED VIOLATION:

The violation is correct.as stated.

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2. REASON FOR THE VIOLATION:

During July,1987, Unit 1 was being returned to power after a refueling outage.- As a result, the ' normal operating level of the air ejector monitor. had not been established to serve as al point- of reference. for determining if the monitor was accurately responding to ~ the expected activity in the process stream. In addition, the high alarm setpoint had not been reset based on the ' current. conditions. - Even though' the daily channel checks, which consisted,of a verification of: free needle movement as per Technical Specification requirements, were performed- every .12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> while the monitor was in service, this type of channel check' alone was not adequate to properly. establish operability. - The': failure to conduct the monthly source check based 'on > the fact that <the monitor demonstrated an up scale reading with needle movement in response to; background radiation was caused by an improper interpretation of

' Technical Specification requirements.

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3. CORRECTIVE STEPS WHICH HAVE BEEN-TAKEN AND THE RESULTS ACHIEVED:

q A new performance test (1-PT-46.2) was approved by the Station Nuclear _  !

Safety. and Operating Committee :(SNSOC) on September 17, 1987 and' revised on October 2,1987. The PT was implemented for 'Jnit l' on October '12, .

1987 and requires both the trend and . absolute value. of the air ejector. j radiation monitor be evaluated every four hours. This evhluation provides an independent means of verifying operability of;the air ejector monitor whereby the monitor reading is compared against past~ data and leak rate trends. PT-46.2 also requires that the high alarm setpoint be reviewed every four hours to ensure that the alarm will . actuate 'when the f primary-to-secondary leak rate increases : by' no more than 20 gallonsL per -

day, which assures the monitor alarm setting reflects? current plant '

operating conditions. _ These new surveillance' requirements . are being.

performed in addition to Technical Specification required channel checks which are performed once every eight hour shift per PT-37.

A review has been done of thirty Technical Specification radiation monitoring channels for the past five years to determine if = the current ,

surveillance interval for channel calibrations is adequate. The as-found condition of- ' th-9 channels ' to. measure radiation level. -(isotopic-calibration) and as-found bistable setpoints . for ' alarms and control .

actions were evaluated. No out-of-specification bistable setpoints? were L found and the small. . percentage of out-of-specification '_i sotopic -

calibrations were random in nature and on different channels. As a result, it can be concluded that instrument drift is'not a problem based-on the ~present calibration interval. Based ~on this record,. it is- 1 appropriate to rely on channel checks to verify continued operability 1 when maintenance has not been performed on the channe1~. 1

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4. CORRECTIVE STEPS WHICH WILL BE TAKEN TO AVOID FURTHER VIOLATIONS: ,

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'l A new performance test (2-PT-46.2) will be implemented for Unit 2 before l the unit enters Mode 1 after its current refueling outage. l

- Surveillance procedures for those radiation monitoring channels, which q per Technical Specifications, require source checks will be revised to require a source check regardless of whether the monitor is reading ,

onscale in response to background.  !

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) 5. THE DATE WHEN FULL COMPLIANCE WILL BE ACHIEVED:

The Technical Specification requirement to perform source checks will be addressed in the appropriate surveillance procedures and 1-01emented by.

} l January 15, 1988. j i

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