ML20205G735

Responds to NRC Re Violations Noted in Insp Repts 50-327/85-27 & 50-328/85-28.Corrective Actions:Maint Instruction MI-10.1 Rewritten to Minimize Coordination Problems & Ensure That Work Instructions Match Data Sheets

ML20205G735
Person / Time
Site:	Sequoyah
Issue date:	11/01/1985
From:	Shell R TENNESSEE VALLEY AUTHORITY
To:	Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
NUDOCS 8511130325
Download: ML20205G735 (7)

Text

f' bMS TENNESSEE VALLEY AUTHORITY CHATTANOOGA. TENNESSEE 37401 400 Chestnut Street Tower II 85Nov 1 alg; ;5 November 1, 1985 U.S. Nuclear Regulatory Comission

. Region II ATTN:

-_Dr._J. Nelson Grace, Regional Administrator

~101 Marietta Street, NW, Suite 2900 Atlanta, Georgia' 230323

DearDr. brace:

SEQUOYAH NUCLEAR PLANT UNITS 1 AND 2 - NRC-OIE REGION II INSPECTION REPORT 50-327/85-27 AND 50-328/85 RESPONSE TO VIOLATIONS Enclosed is our; response to R. D. Walker's October 1, 1985 letter to

H.' G. Parris transmitting IE Inspection Report Nos. 50-327/85-27 and 50-328/85-28 for'our Sequoyah Nuclear Plant which cited TVA with two Severity Level IV Violations'and one. Severity Level V Violation.

-If you'have any questions, please get in touch with R. E. Alsup at FTS 858-2725.

To the best'of my kn31 wedge, I declare the statements contained herein are

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complete and'true.

Very truly yours, TENNESSEE VALLEY AUTHORITY a

• R. H. Shell Nuclear Licensing Branch Enclosure ec:

Mr. James Taylor, Director (Enclosure)

Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.

20555 8511130325 851101 PDR ADOCK 05000327 G

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3 RESPONSE ~- NRC-01E INSPECTIONLREPORT.

NOS. 50-327/85-27-AND'50-328/85-28 ROGER D. WALKER'S LETTER TO H. G. PARRIS DATED OCTOBER 1, 1985

, Violation' 5'0-327/85-27 and 50-328/85-28-01

Technical Specification 6.8.1: requires that written procedures be estab-g Elished., implemented and maintained covering safety related activities referenc'ed in Appendix' A of Regulatory Guide 1.33, Revision 2, February -

1978.- Maintenance Instruction MI-10.1, Diesel Generator. Inspection, limplements'this requirement during maintenance activities on the diesel generators..

Contrary to the above, the following portions of MI-10.1 were not imple-imented during performance of the procedure on August 14, 1985.

a..

Step 5.4.'1.1 of MI-10.1 directs the technician to use low pressure -

air to remove dust from the diesel. generator collector. rings and.

stator. This step was not implemented in that the inspector observed

a. technician checking this step complete without having used low pressure air to clean the collector rings and stator.

b.

Step '5.4.1.2lof MI-10.1 dir'ects the technician to ' remove oil, grease H

or accumulation of' dirt from the diesel generator collector with

-; clean,' bound end, lintless wiping cloths. This step was not ade-

- quately ' implemented in that the inspector observed a technician using knit material without bound ends to clean the diesel generator collector.

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Step 5.4.1.8 of MI-10.1 directs the technician to check-frame hold down and foundation bolts to see that they are tight and to record -

results and'any unusual findings on' Inspection Sheet 5.4.

This step was not~ implemented during the performance of MI-10.1.

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-These"three examples together constitute a Severity Level V violation (Supplement I).

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Admission o'r Denial of the Alleged Violation TVAcadmits the violation occurred.

2.s Reason for the' Violation

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a.'

During performance of.MI-10.1, electrical' maintenance personnel inspected the inside~of the generator as required by the

. instruction for dust. There was no accumulation of dust present, and subsequently, they did not use low-pressure air'during the inspection. A contributing cause to the failure to follow pro-

- cedures is the_ lack of a signoff on the data sheet used in MI-10.1.

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When this instruction was written, lintless bound-end' cloths

=could-be purchased from Power Stores to remove oil.. grease, or

- accumulation of-dirt from. the diesel generator. The Power

- Storesino. longer has bound-end cloths available; furthermore,

- bound-end cloths were called;out' in the procedure simply because they were available.

MI-10.~1;is performed in part by both electrical maintenance (EM) c.

and-mechanical maintenance (MM)' personnel. When the EM personnel-reached thelpoint in the procedure for inspection of the frame ihold down and foundation bolts, they assumed this to be a MM func-tio n.~. MM was. working under the _aasumption.that EM had performed

' this work. This lack'of coordination was further degraded by the

. lack of a signoff on the MI-10.1 data sheet to indicate that the.

step had.been performed.

3.

Corrective Steps Which Have Been Taken and Results Achieved Technicians involved have been counseled on.the errors made and atten-tion to details. Temporary changes to MI-10.1 were made to add signoff for use of low-pressure air, if needed, to remove dust and for inspec--

tions of bolts.. Also the requirements for bound-end cloths were-removed.

-4..' Corrective-Steps Which Will Be Taken To Avoid Further Violations

'MI-10.1 will undergo a complete rewrite to minimize coordination

' problems and to ensure work instructions match data sheets. This

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revision will be complete by January 13, 1986.

5. -Date-When Full Compliance'Will Be Achieved Full: compliance was~ achieved on Octobe'r 22,- 1985, when the instruction J

was changed to add data sheet signoffs.

JViolation' 50-328/85-28. Technical Specification.3.5.1.1 requires that each cold leg injection accumulator shall be operable with the. isolation valve open, contain a -

. volume of borated water-between 7857 and 8071 gallons with a boron con-centration between 1900 and 2100 ppm, and a nitrogen cover-pressure of between 385;and 447 psig. With'one cold leg-injection accumulator inoperable, except_ as a result of a closed isolation valve, the inoperable accumulator must be restored.to operable status'within one hour or the J

reactor.must be placed in at least Hot Standby within the next six hours o

- and Hot ; Shutdown within the following six' hours.

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Contrary co :the above, on August 19 and.10,.1985, the Unit 2 number 3 loop

cold leg _ injection accumulator was technically inoperable in that it did not contain a volume of borated water between 7857 and 8071 gallons or a

. concentration of boron between 1900 and 2100 ppm for a period of seven

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Lhours'and forty 4 minutes. This exceeded the requirement to be in Hot

. Standby by forty minutes.

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-This'is?a SAverity Level IV violation (Supplement I).-

This applies to

Unit'2 only..

1.'

Admission or Denial' of the Alleged Violation

~ TVA admits. the violation occurred as stated.

.- 2. Reason for the Violation.

(When.the? loop 3 accumulator was declared inoperable at 1740 CST, the c

boron concentration was within limits. From 1740 CST until 1830 CST

' when' the boron sample was taken,' the accumulator was being drained for refilling'from the refueling water storage tank (RWST) which contained greater than 2000. ppm borated water.

Since.there had been "no dilution water added 'to the accumulator, the 1830 CST boron sample.was suspect and not thought to be accurate. At 2212 CST, the

. limiting. condition for operation (LCO) was exited when-the cold-leg

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- accumulator level and pressure was returned within allowable limits.

' Af ter :the completion of;the refilling of the loop 3 accumulator, another sample was. required to be taken as specified in System Operating

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-Instruction (SOI)-63.1A used for the filling process. This was done bys the Chemical Laboratory at 2350 CST, and when. the sample came back.

less-than 1900 ppm, the loop 3 accumulator was declared inoperable at 0002 CST.

The procedure requires that the operator notify Chemical Laboratory to

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'obtain a. sample for boron verification within six hours -af ter draining and. refilling. This was followed.by the operator and is consistent with Technical Specification LCO 4.5.1.1.1.b.

-The two deficiencies which contributed to this violation were (1) a deficient procedure which allowed obtaining a boron sample during the filling and ' draining process, and (2) a personnel error in that operai tions. personnel failed ~ to consider the los. boron concentration before declaring.the cold-leg accumulator operable.

3. ' Corrective Steps Which 'Have Been Taken and Results Achieved The loop 3 cold-leg accumulator was returned within technical specifi-cation limits in all parameters at-0200 CST on September 10, 1985.

_ 4. : Corrective-Steps Which Will Be Taken To' Avoid Further Violations f

'JL caution note will be added 'to both the draining and filling portions of SOI-63.1 concerning-the potential for uncertainties of boron samples

taken'during these processes. A training letter wil1~be issued to licensed ' personnel discussing this event and the changes being made to

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SOI-63.1.

Both of these corrective actions will be completed by December 31, 1985.

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i L5.. Date' When' Full Coupliance Will Be Achieved 4

-Full compliance was achieved on September 10, 1985, when this loop 3

- cold-leg accumulator was returned within technical specification

- limits.

J V'iolation 5d-327/85-27-04

, Technical Specification'6.8.~1 requires that written procedures be estab-lished, implemented and maintained covering safety related activities m

referenced in Appendix A of Regulatory Guide 1.33, Revision 2, February.

'1978... Technical Instruction TI-51, Assignment of Detailed Test Methods

'and' Responsibility for Non-Destructive Testing, implements this requirement in the area of.non-destructive testing.

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~ Contrary to the above,- TI-51' was not adequately implemented on July 31,

-ipS5'during a nondestructive liquid penetrant test.of the Unit 1 CVCS

letdown sample-line. ' This resulted in the failure to identify a crack

.in:the. sample -line which existed approximately one third way through the -

' wall thickness.

Independent analysis of ~ the failure identified both dye 4

penetrant and ' developer inside the crack indicating that the crack existed l when the ' examination was conducted. The existing crack resulted in a JCVCS letdown line leak on August 11, 1985.

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This is~ a Severity. Level IV. violation (Supplement I)..This applies to Unit 1 only.

1.

Admission or Denial'of the Alleged Violation TVA agrees a violation occurred.

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2.1 Reason for the Violation

On July 29, 1985, SQN unit 2 experienced a leak in the chemical and -

volume-control (CVC) system at a sample line connection ~ upstream of valve 2-62-674.. This event is discussed in Licensee Event Report.

oS0-327/85031.. Following the unit 2~ event, plant management pursued a course of' action to inspect the similar. connection on unit 1.

As part of the' inspection, the unit 1 CVCS sample line connection at-

- valve 1-62-674 was examined visually and.by liquid penetrant exam-s ination. There were no flaws or indications noted.

However,.sub -

sequent.to the. visual inspection, a small: leak was noted on the unit I

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sample line'on August 11, 1985.

The-personnel involved in the actual. visual and liquid penetrant examination were nondestructive examiner (NDE) level II certified inspectors from TVA's In-Service Inspection (ISI) Group. Prior

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to the actual performance of the examination, the inspectors dis-

-cussed;with SQN's; metallurgical engineers and plant management the p3~

. location.of the piping section.. The inspectors were instructed that area of the failure on unit 2 -and the difficulty associated with the n

. this - examination was for-determining if a similar flaw could be

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detected on-unit 1.

The inspection was performed using Technical

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Instruction (TI)-51, " Assignment of Detailed Test Methods and

-Responsibility for Non-Destructive Testing," and in particular N-PT-3, '" Liquid Penetrant Examination Using Color-Contrast Solvent-Removable Method For ' Elevated Temperature Examinations."

following the unit I leak, extensive interviews were held with the

. personnel involved who stated that the examination was performed in_accordance with procedures, and they did not detect any flaws in the areas ~ examined. The inspectors were also requested to per-form a mock penetrant test (PT) inspection at the actual sample line location after it was repaired. This was accomplished and witnessed by plant management. The inspectors demonstrated they knew and could adequately implement the procedure. -

The' metallurgical failure analysis of the CVCS pipe by Combustion

' Engineering indicated that dye penetrant and developer were found within the crack.

It was further concluded that based on the presence of the dye penetrant and developer, the crack existed at the time the PT was performed. This is one possible explanation.

-It is also possible that the dye penetrant and developer were intro-duced after the leak as a contaminant during the removal and shipment process.

TVA believes the violation that occurred is -that a crack developed in the sample line connection and that TVA was unabl9 to detect the

. crack during examination following the unit 2 failure. However, the inspectors believe that the liquid penetrant examination was performed as prescribed in TI-51, and TI-51 was correctly implemented.

The cause for failure to detect the crack during examination is indeterminate. Several possible explanations are as follows:

'l.

Although unlikely, the crack did not exist at the time of the PT g

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failure.

2.

The crack existed but was so tight that at the time of examination was not detectable.

3.

The crack existed, was detectable, and an unintentional personnel error occurred while looking for the penetrant bleedout which l

iresulted in the crack going undetected.

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Af ter discussion with the inspectors and a thorough review of the Combustion Engineering report, TVA believes that the above are pos-sible explanations for the crack to go undetected in addition to the possible failure to adequately implement the procedure.

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Corrective Steps Which Have Been' Taken and the Results Achieved The cracked pipe in the sample -connection was removed and replaced with new material ~. A detailed corrective action and evaluation plan has been developed by plant management to detect and prevent future similar failures. This was previously submitted to NRC in a letter from H. G. Parris to J. Nelson Grace dated August 28, 1985.

'This event has been discussed with the inspectors involved by numerous TVA management personnel. Furthermore, other ISI inspectors and plant quality assurance inspectors have been made aware of the event.

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Corrective Steps Which Will Be Taken to Avoid Further Violations See se'ction 3 above.

5.. Date When Full Compliance Will Be Achieved There is not enough substantial evidence to positively conclude when or if a noncompliance of implementing the procedure occurred. TVA assured compliance upon completion of the discussion with the inspectors.

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