ML20012B843

Proposed Tech Specs Modifying Unscheduled Steam Generator Tube Insp Requirements After Primary to Secondary Leak in Excess of Spec 3.1.6.3 Limits

ML20012B843
Person / Time
Site:	Three Mile Island
Issue date:	03/12/1990
From:	GENERAL PUBLIC UTILITIES CORP.
To:
Shared Package
ML20012B825	List: ML20012B824 ML20012B827 ML20012B843
References
NUDOCS 9003160419
Download: ML20012B843 (6)

Text

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Lo.: - "med inservion inspection shall~ include Ct least 3% of .the total runnbar of tubes in all steam generators; the-tubes selected for these

, inspections shall be selected on a randam basis exampt:

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' a. 'the first sanple of tubes selected for and inservice.

L inspection (subsequent to the preservice inspecticsi). of ,

eam steam generator shall include  ;

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1. All ncrplugged tubes ~ that previously had detectable wall penetrations (>20%)..

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2. 'At least 50% of the tubes inspected shall be in s thoas areas where experience has indicated potential i problems.n

3. A tube inspection (pursuant to Specification 'I 4.19.4.a.8)-shall be performed on en& selected tube.

l If any selected tube does not permit the passage of the eddy current probe for a tube inspecticri, this shall be recorded and an adjacent tube shall be selected and subjected to a tube inspection.

4. Tubes in the following groups may be excluded from the first randcza sanple if all tubes _in a group in both j steam generators are irupacted. No credit will be  ;

taken for these tubes in meeting mininum sanple size requirements.

I (1) Group A-1: 'Ibbes in rows 73 through 79 adjacent to the open i W _ ion lane, and tubes between and on lines drawn fran tube 66-1 to tube 75-15 and from 3 86-1 to 77-15.

(2) Group A-2: Tubes having a drilled opening in the .

p 15th support plate. y

b. '1he tubes selected as the second and-third sanples- (if. '

required by Table 4.19.2) during eacts inservice inspection may be subjected to a partial tube i W lan provided:

r l 1. 'Ihe tubes selected for these second and third sanples include the tubes from those areas of the tube sheet array where tubes with imperfections were previously found.-

2. 'Ihe inspection includes those portions of the Sh where imperfections were previously_ found.

'Ihe results of each sanple inspection shall be classified into one of the following three categories:

Cateaory Insoection Results C-1 Less than 5% of the total S h inspected in a steam generator are degraded hihan and none of the inspected tubes are defective.

Amendment No. 47 (12-22-78) 4-78

'9003160419 900312 h C

1. PDR./ADOCK 05000289

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'* '. C-2 One or more tubes, kut not are than 1% of the total .l tubes inspected in a steam generator are defective, or

'* - I between 5% and 10% of the total tubes inspected are.

degraded tubes. -l i

C More than 10% of the total tubes inspected in a' steam "

generator are degraded tubes or more than 1% of the inspected tubes are defective. i

, NOIES: (1) In all inspections, previously degraded tubes must exhibit significant (>10%) further wall p- Lations to be included in the above p=v-dage calculations.

(2)- m ere special inspections are performed pursuant to 4.19.2.a.4, defective or degraded tubes found as a .

result of the inspection shall be included in deter-mining the Inspection Results Category for that v b l inspection but need not be included in determining the Inspection Results Category for the general steam generator inspection.

!- 4.19.3 Inarwtion Freauencies  ;

'Ibe required inservice inspections of steam generator tubes shall be perfomed at the following frequencies:

a.Ihe first (hanaline) inspection was performed after 6 effective full power months but within 24 calendar months u of initial criticality. 'Ihe subsequent inservice

!. inspections shall be performed not more than 24 calendar months after the previous inspection. If the results of L two consecutive inspections for a given group'of tubes *  ;

" . enocupassing not'less than.18 calendar nonths all- fall into the C-1 category or demonstrate that previously i observed G.: pad & tion has not continued and no additional day.adation has occurred, the inspection interval for that ~

group may be extended to a =vi== of once per 40 months.

'b. If the results of the inservice inspection of a steam i generator ocnducted in accordance with Table 4.19-2 at 40 month intervals for a given group of tubes

• fall 11nto '

category C-3 the inspection frequency for that group shall be. increased to at least once~ per 20 nonths. 'Ihe increase in inspection frequency shall apply until the eiha-pent inspections satisfy the criteria of Specification 4.19.3.'a; the interval may then be extended to a =v4== of once per 40 months

c. Additimal, unscheduled inservice inspections shall be performed on each steam generator in accordance with the first sanple inspectim specified in Table 4.19-2 during the shutdown 9thaaq =nt to any of the following conditionc:

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• A group of tubes means:

(a) All tuhm inspected pursuant to 4.19.2.a.4, or (b) All tubes in a steam geir.rator less those inspected pursuant to 4.19.2.a.4

. Alissi bruit No. 47 L(12-22-78) 4-79

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.'I ik A seisualc occurrence greater than the.Operatig Basis f Ac ' "

. Earthquake.

2.- A' loss of coolant acciderst requirirg actuation'of-  ;

engineerirg safeguards, or

3. A major main steam line or feedwater line treak. -

~-,; . .d. After primary-tc haiery tube leakage (not including leaks originating frtan tube-tMube sheet wlds) in avr===

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of the-limits of Specificaticm 3.1.6.3, an inspection

• of the affected steam generator will be performed in i accan$ance with the followirg criteria:

1. If the-leak'is above the 14th tube eqppart plate in a Group as defined in Section 4.19.2.a.4(1) all of the tubes-in this Group in the affected steam generator will ,

be inspected above the 14th tube support plate. If the results of this inspection fall into the C-3 category, additional inspections will be performed in the same Group in the other steam generator.

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2. If the leaking tube is not as defined in Section 4.19.3.d.1, than an inspection will be performed on the affected staan generator (s) in accartlance with Table-4.19-2.

F 4.19.4 Acceptance Criteria

a. As used in this specification:

1. Inperfection means an exception to the dhnansions, finish or contour of a tube frcan that required by fabrication drawing c:: specificaticos. B$dy current testing indi-cations.below 20% of the ncaninal tube wall thickness, -if detectable, may be considered as -inperfections.

2. Degradaticm means a service-irvtvnd cracking, wastage, wear or general carrosion occurring on either inside or outside of a tube.

3. Dearaded 'I\1be means a tube containing inperfections 220% of j g

i the naminal wall thickness caused by degradation.  !

4. % w tion means the percentage of the tube wall thickness affected or removed by de:pwdation.

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5. Defect means an inperfection of such severity that it ,

eynaada the repair limit. A tube containing a defect is I defective.

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4-80 Amerdment No. 116, 149 I

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4.19.4 Acceptance Critaria-(contimed) l

6. Repair Limit means the extent of degredation at or beyond  !

which the tube shall be repaired or rummed frun service = l har=n=a it any h unserviceable prir to the next I g inspection.--

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'Ihis limit is equal to 40% of the ncaninal tube wall i thickness.

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7. Unserviceable rimanribes the candition of a tube if it leaks or cantains a defect large enough to affect its  ?

structural integrity in the event of an Operating Basis 1 Earthcpake, a loss of coolant accident, w a steam line or ,

feedwater line break as specified in 4.19.3.c., above. '

8. Tube Inspection means an inspection of the steam generator  ;

tube frun the bottom of the upper tubenheet ocupletely to the top of the_ lower hihaaheet, avr=t as permitted by

.4.19.2.b.2, above.

b. h steam generator shall be determined OPERABLE after ,

coupleting the wuaspermiing actions (removal frun service by plugging, or repair by kinetic expansion, sleevirxJ, or other methods, of all hihan hing the repair limit and all tubes containing throughwall cracks) required by Table 4.19-2. l 4.19.5 Reports

a. Following the cxmpletion of each inearvice inspection of steam generator tubes, the number of tubes repaired or removed fran service in each steam generator shall .'

be reported to the NRC within 15 days,

b. 'Ihe ocuplete results of the steam generator tube inservice inspection shall be rarn.Und to the NRC within~ 3 months following completion of the inspection.

'Ihis rar.aL shall include:

1. Number and extent 'of hihaa inspected. . '!

2. Incation ard p=uvuut. of wall-thickness parnhation for each indication of an imperfection. '

3. Identification of hihaa repaired or renoved frcan service.

c. Results of steam generator tube inspections which fall into category c-3 require notification in accordance with 10 CPR 50.72 prior to resunption of plant operation. h written followup of this rar.ut shall provide a description of investigations corducted to determine the cause of the tube degradation and corrective measures taken to prevent recurrence in accordance with 10 CFR 50.73.

4-81 Amendment No. 47, 83, 91, 103, 129, 149

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,The surv'elllance Requirements for inspection of the steam generator .I tubes ensure that the structural integrity of this portian of the Ras will be maintained.-

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l' - The program for inservice inspection of steam generator tubes is ~ j based on modification of Regulatory Guide 1.83, Revision 1. In- i service inspection of steam generatz tubing is essential in order to maintain surveillance of the canditions of the tubes in the i event that there is evidence of mechanical <h=arja or progressive I degradaticri due to design, mamfacturing errors, or inservice .l conditions. Inservice inspecticri of steam generatz tubing also provides a means of characterizing the nature and cause of any. tube l degradation so that wJve mananus can be taken.

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. The Unit is expected to be aperated in a manner such that the primary and secondary coolant will be maintained within those chamistry limits found to result in negligible carrosion of the steam generator L

hihaa. If the primary or secondary coolant absmintry is not E maintained within these chemistry limits, localized carrosian may  ?

likely result.

The extent of steam generator tube leakage due to crackirg would be limited by the secondary coolant activity, Specification 3.1.6.3. <

The extent of cracking durinry plant aparation would be limited by the limitation of total steam generator tube leakage between the primary ,

coolant system an$ the secondary coolant system (primary-

• tc>-se.udary leakage = 1 gpm) . La=W in excess of this limit will

' require plant shutdown and an unschedaled-inspection, during which the. leaking tubes will be located and repaired or removed from '

service.

Wastage-type defects are unlikely with y w chemistry treatment of the primary or the secondary coolant. However, even if a defect would develop in service,-it will be found during adsarbled in-service steam' generator tube examinations.- Steam generator tube inspections of aparating plants have demonstrated the capability to reliably detect degradation that has pic= Luted 20% of the original tube wall thickness.

Removal fr a service by plugging, or repair by kinetic expansion, sleeving, or other methods, will be required for degradation equal to

l. L or in eynasia of 40% of the tube naminal wall thickness. -

l Where experience in similar plants with similar water chenistry, as +

L d<v'manted by USNRC Bulletins / Notices, indicate critical areas to be i: inspected, at least 50% of the hihan inspected should be frca these critical areas. First sanple inspections sanple size may be modified

- subject to NRC review and approval. '

4-82

% Erdiant No. 47, 86, 116, 149

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g, i LNITED STATES OF AMERICA' l

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NUCLEPR RBARA'IGN 03 MISSION .

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- IN 'IHE MA' ITER OF. DONET NO. 50-289 ,

GPU NUCLFAR CCRPORATION IJCENSE NO. DPR-50

}

r CERI'IFICATE OF SERVICE '

This is to cartify that a copy of Technical Specification Change Request No.199 to Appendix A of the Operating License for 'Ihree Mile Island Nuclear Station Unit 1, has, on the date given below, been filed with ava,itives of Is-As.Luy ,

'Ibwnship, Dauphin County, Pennsylvania; Dauphin County, Pennsylvania; and the -

Pennsylvania Department of Envitss=mial Resources, Bureau of Radiation Protection, by deposit in the United States mail, addramaaA as follows:

Mr. Kenneth E. Witmer, Chairman Ms. Sally S. Klein, Chairman i Board of Supervisors of Board of County Otzmissioners Ionder.Muy 'Ibwnship of Dauphin County -

25 Roslyn Road Dr.uphin County Courthouse Elizabethtown, PA 17022 HarriahirtJ, PA 17120 Mr. '1hcnas Gerusky, Director PA. Dept. of Envirss== ital Paaruiroes ,

Bureau of Radiation Protection P.O.' Box 2063 Harrisburg, PA 17120-GPU NUCLEAR CORIORATION. t BY:

V16ehident & Director, 'IMI-1 ,

DATE: 3A./ro

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