ML20207E685

Responds to NRC Re Violations Noted in Insp Repts 50-327/98-11 & 50-328/98-11.Corrective Actions:Lessons Learned from Event Have Been Provided to Operating Crews

ML20207E685
Person / Time
Site:	Sequoyah
Issue date:	03/02/1999
From:	Bajestani M TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
50-327-98-11, 50-328-98-11, NUDOCS 9903110044
Download: ML20207E685 (7)

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Ton,essee Valley Authority, Post Of6ce Box 2000, Soddy Daisy, Tennessee 37379-2000 Masoud Bajestani Site Vice President Sequoyah Nuclear Plant March 2, 1999 U.

S. Nuclear, Regulatory Commission 10 CFR 2.201 ATTN: Document Control Desk Washington, D.C.

20555 Gentlemen:

In the Matter of

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Docket Nos. 50-327 Tennessee Valley Authority

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50-328 SEQUOYAH-NUCLEAR PLANT (SQN) - NRC INSPECTION REPORT 50-327, 50-328/98-11 -' REPLY TO. NOTICE'OF VIOLATION (NOV)

This. letter.provides our reply to the.NOV.

The.NOV

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contains two violations as documented in the subject

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inspection report dated February 1, 1999.

One violation addresses the failure to properly implement an emergency procedure following a reactor trip on November 9, 1998.

The other violation was for a failure to enter Technical Specification (TS) 3.0.3 when the limiting condition for reactor coolant system flow instruments was not met.

jd The enclosure contains TVA's response to the NOV.

This submittal does-not contain' additional commitments.

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{DR -ACDCK 05000327 5 een j 3:.

I U.S. Nuclear Regulatory Commission Page 2 March 2, 1999 If you have any questions regarding this response, please contact me at extension (423) 843-7001 or Pedro Salas at extension (423) 843-7O.

Sincerely, I

- D 4r M.

Bajes i

Enclosure cc (Enclosure)

Mr. R.

W.

Hernan, Project Manager Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852-2739 NRC Resident Inspector Sequoyah Nuclear Plant 2600 Igou Ferry Road Soddy-Daisy, Tennessee 37379-3624 Regional Administrator U.S.

Nuclear Regulatory Commission Region II Atlanta Federal Center 61 Forsyth Street, SW, Suite 23T85 Atlanta, Georgia 30303-3415 J

ENCLOSURE TENNESSEE VALLEY AUTHORITY SEQUOYAH NUCLEAR PLANT (SQN)

UNITS 1 AND 2 INSPECTION. REPORT NUMBER 50-327, 50-328/98-07 REPLY TO NOTICE OF VIOLATION (NOV)

I.

RESTATEMENT OF VIOLATION A (50-328/98-11-02)

" Technical Specification 6.8.1.a requi res, in part, that procedures shall be established, implemented, and maintained covering activities recommended in Appendix A of Regulatory Guide 1.33, Revision 2, February 1978, ' Quality Assurance Program Requirements (Operations).'

Regulatory Guide 1.33 Appendix A, Paragraph 6 recommends procedures for combating emergencies and other significant events.

Emergency Subprocedure (EOP) ES-0.1, Reactor Trip Response, Revision 22, Step 3.c.,

contains the continuous action requirement 'IF temperature greater than 552 F and rising, THEN... DUMP. steam USING atmospheric reliefs.'

Step 3 of the j

subprocedure foldout page, which presents actions which apply at all times during procedure performance, also contains the requirement to ' MONITOR reactor coolant system (RCS) temperatures stable at or trending to between 547 F and 552 F.'

EOP ES-0.1, Reactor Trip Response, Revision 22, step 8.b.,

contains the continuous action requirement 'IF pressure greater than 2235 psig and rising, THEN... CONTROL pressure USING one pressurizer power operated relief valve (PORV).'

Step 8.b.2 of ES-0.1 foldout page also contains the requirement '(if pressurizer pressure greater than 2235 psig and rising) CONTROL pressure.'

Contrary to the above, following a Unit 1 reactor trip on November 9, 1998, the procedural requirements of EOP ES-0.1 were not properly implemented, in that:

1.

RCS temperatures were not monitored, stable and trending to between 547 F and 552 F and subsequently steam was not dumped using the atmospheric reliefs when RCS temperature was greater than 552 F and rising.

RCS temperatures exceeded 552 F for a period of approximately 23 minutes.

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2.

RCS pressure was not controlled using one pressurizer PORV when RCS pressure was greater than 2235 psig and rising.

RCS pressure exceeded 2235 psig for approximately 25 minutes.

This is a Severity Level IV Violation (Supplement 1)."

TVA'S REPLY TO THE VIOLATION 1.

Reason For Violation A (50-328/98-07-02)

Based on an evaluation of the condition, the root cause for the violation was the crew's failure to properly monitor plant parameters.

Contributing causes were a

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combination of understanding procedural flow path and hierarchy following a reactor trip due to equipment / component failures that effect post trip response; the role, priorities, and focus of the unit supervisor and shift technical advisor; desirability of having controlling bands in ES-0.1; and lack of training crews on reactor trips concurrent with the loss of inverter (. abnormal operating procedure (AOP) type events).

As a result of these causes, the operating crew did not take mandal control of the steam generator (SG) atmospheric. relief valves and maintain reactor coolant (RCS) temperature.

Based on past operating practice, industry practice, and consistent with previous operator training, the crew chose to control pressure using the pressurizer power-operated relief valves in automatic.

2.

Corrective Steps Taken And Results Achieved Lessons learned from the event have been provided to the operating crews.

Each crew is familiar with the event and the deficiencies that have been identified.

The operating crew has been counseled on their individual and collective performance deficiencies.

Their understanding and correction of these deficiencies have been demonstrated through successful simulator performance.

Additionally, the other licensed operators have had simulator training on the reactor trip wito loss of the 1-IV vital inverter transient.

Based on this training, licensed operators fully understand the

'importance of closely monitoring and controlling the RCS

' temperature during these types of transients.

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As an. interim action to the evaluation of operator performance for the November 9, 1998 Unit 1 trip, an independent review was' performed.

The review team consisted of a Westinghouse Nuclear Services representative,Lthe Comanche Peak Operations Support Manager,' the McGuire Operations Training Manager, the Watts Bar Operations Training Manager, a senior operator from the Sequoyah Operations Training Department, and a Sequoyah Operations unit supervisor.

i The team reviewed the reactor trip report, observed the performance of three operating crews responding to a reactor trip with a loss of Vital Instrument Power I

Board 1-IV on the simulator, and reviewed plant procedures used to respond to this type of event.

Enhancements to the emergency operating procedures (EOPs) were identified, which will eliminate the 1

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- confusion added by having a parenthetical operating band in the " Action / Expected Response" column.

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Recommendations made by the independent review have been l

incorporated into the Corrective Action Program as I

" Actions" and are being tracked to completion.

I Following the; independent review, simulator training sessions were held with each crew for a loss of the i

Vital Instrument Power Board 1-IV with a reactor trip scenario.

These training scenarios exposed the crews to tne lessons learned (monitoring and controlling RCS L

temperature) and reinforced expectations regarding I

command and control, communications, and proper procedure usage.

Following each scenario, crew specific critiques were held that discussed crew performance.

These critiques did not discuss crew differences to preserve the independence of each crew.

A supplementary intent of these scenarios was to gather information'on individual crew response to capture the best combination of plant parameter control and procedural pace that would' provide the most effective mitigative strategy for this scenario.

The training analysis data from each crew is to be combined with benchmarking data from training observations recently made at three 2

Westinghouse sites to further enhance EOPs and AOPs.

Additional' scenarios are being conducted with other AOPs to identify if similar conflicts exist between AOPs and EOPs.

This will result in further procedure

. enhancements.

These procedural enhancements,.along with expectations concerning the role of crew members,

. procedural hierarchy, and monitoring plant parameters, will be provided to operators in future training cycles.

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Corrective Steps That [Have Been Or) Will Be Taken To Prevent Recurrence No additional-actions are necessary relative to the cause of the violation.

4.

Date When Full Compliance Will Be Achieved With respect to the violation, TVA is in full compliance.

II. RESTATEMENT OF VIOLATION B (50-328/98-07-01)

" Technical Specification 3.3.1.1 requires that the reactor trip system instrumentation channels and interlocks of Table 3.3.-1 shall be operable.

Table 3.3-1, Functional Unit 12, Loss of Flow-Single Loop, requires a minimum of 2 RCS flow channels per loop to be operable in Mode 1.

Technical Specification 3.0.3 requires, in part, that when a Limiting Condition for Operation is not met, except as provided in the associated action requirements, within one

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hour action shall be initiated to place the unit in a MODE in j

which tho Specification does not apply.

l Contrary to the above, Technical Specification 3.0.3 was not met, in that on November 20, 1998, all three channels of the Unit 1 RCS Loop 1 flow instruments (1-F1-68-6A, 6B & 6D) were l

inoperable, indicating off-scale high, and TS 3.0.3 was not entered to initiate action to place the unit in a MODE in j

which the Specification does not apply (Mode 2 or less).

This is a. Severity Level IV Violation (Supplement 1)."

TVA'S REPLY TO THE VIOLATION 1.

Reason For Violation B (50-328/98-11-01)

The reason for the violation was our interpretation of Technical Specification (TS) 4.0.3 applicability.

The individuals involved incorrectly believed that entry into TS 4.0.3 was acceptable based on an evaluation that the computer data for Unit 1, Loop 1, RCS flow was valid and that the surveillance could be performed successfully if the procedure was revised to allow use of the computer data.

As a result, we failed to understand that TS 4.0.3 does not apply to a surveillance, which could not be performed.

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2.

Corrective Steps Taken And Results Achieved The Operations Superintendent issued an Operations Department Standing Order to the shift crews.

The standing order reinforces the correct use of TSs 4.0.3 and 3.0.3.

The standing order states that TS 4.0.3 entry for the RCS flow indication condition was inappropriate.

The operating-crews have reviewed the standing order and understand correct application of TS 4.0.3.

The SON site management team discussed TSs 4.0.3 and 3.0.3' entries and applicability.

The management teaa and the Operations department now understands that the TS 4.0.3 entry was an inappropriate decision and that a TS 3.0.3 entry was required.

3.

Corrective Steps That [Have Been Or] Will Be Taken To Prevent Recurrence No additional actions are needed to prevent recurrence.

4,.

Date When Full Compliance Will Be Achieved With respect to the violation, TVA is in full compliance.

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