ML20059N030

Safety Evaluation Accepting Util Response to Generic Ltr 88-01, NRC Position on IGSCC in BWR Austentic Stainless Steel Piping

ML20059N030
Person / Time
Site:	LaSalle
Issue date:	08/22/1990
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20058K090	List: ML20058K086 ML20058K092 ML20058K136 ML20059N029 ML20059N030
References
GL-88-01, GL-88-1, NUDOCS 9010090048
Download: ML20059N030 (3)

Text

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• "4W,'g _ ENCLOSURE 2 UNITED STATES i8 e-NUCLEAR REGULATORY COMMISSION

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\.....l l ENCLOSURE SAFETY. EVALUATION BY.THE OFFICE OF. NUCLEAR REACTOR-REGULATION EVALUATION 0F WRC GENERIC. LETTER 88 01. RESPONSE E

COMMONWEALTH EDISON LASALLE COUNTY. STATIONS. . UNITS 1 and 2 I l DOCKET N05. 50 373.and.374 -

1.0_ INTRODUCTION Commonwealth Edison, the licensee, submitted its' response to NRC Generic Letter (GL) 88-01, "NRC Position on IGSCC in BWR Austenitic Stainlass Steel Piping" for l;: LaSalle-County Stations, Units 1 and 2, by letter dated July 29,1988, and addi-tional information as requested by the staff was provided by letter dated June 30, 1989. GL-88-01 requested Licensees and construction permit holders to resolve the

-IGSCC issue for BWR piping made of austenitic stainless steel that is 4 inches or larger in nominal diameter and contains reactor coolant at a' temperature above 200 degrees Fahrenheit during-power operation regardless of Code classification. The licensee was requested to address the following:

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1. The current plans regarding pipe replacement and/or other measures taken to mitigate IGSCC and provide assurance of continued long term integrity and reliability. ,

2. The Inservice Inspection (ISI) Program to be implemented at the _next refuel-ing outage for austenitic stainless steel piping covered under the scope of GL-88-01 that conforms to the the staff positions on inspection schedules.

methods and personnel, and sample expansion included in GL-88-01. .

3. .The Technical Specification change to include a statement in the section on ISI that the ISI Program for piping covered by the scope of this letter will be in staff positions on schedule, methods and personnel, and sample expan-

. sion included in GL-88-01 (See model BWR Standard Technical Specification enclosedinGL-88-01). It is recognized that the Inservice Inspection and

^ Testing sections may be removed from the Technical Specifications Improvement programs. In this-case, this requirement shall remain with the ISI section fwhen it is included in an alternative document.

4. The confirmation of your plans to ensure that the Technical Specifications related to leakage detection will be in conformance with the staff positions on leak detection included in GL-88-01.

5. The plans to notify the NRC in accordance with 10 CFR 50.55a(g) of any flaws identified that do not meet IWB-3500 criteria of Section XI of the Code for-continued operation without evaluation, or a change found in the condition of the welds previously known to be cracked and your evaluation of the flaws for continued operation and/or your repair plans.

9010090048 900822

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4 2.0- DISCUSSION The' licensee's response to NRC GL-88-01 has been reviewed by the staff with the assistance of its contractor, Viking Systems International (VSI). The attached Technical Evaluation Reports are VSI's evaluation of the licensee's response to n NRC GL-88 01. . The staff has reviewed the TERs and concurs with the evaluations, '

conclusions, and recomendations contained in the TERs. In the revfow of the licensee GL-88-01 submittal, the staff finds the following positions'to be unacceptable:

1. The licensee's position not to amend the Technical Specification (TS) to incluot a statement on ISI as required by GL 88-01. 1

2. The licensee's position not to amend the TS to include a requirement of a limiting.the' increase in unidentified leakage to 2 gpm over a period of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or less as-required by GL-88-01.

3. The licensee'_s position not to accept the operability requirements of the leakage monitoring' instruments outlined in GL-88-01 for Unit'1. -

4. The licensee's position that they are exempt from the GL-88-01 frequency requirements to monitor leakage.

For a detailed discussion of these items see sections 2.0'and 3.0, of the attached TERs.  ;

The staff has re-evaluated the frequency of leakage monitoring after discussions with several BWR operators and concluded that monitoring every four hours creates-an unnecessary administrative hardship to the plant operators. Thus, RCS leaka measurements.may be taken every eight hours instead of every four hours as re ge quired in GL-88-01..

3.0. CONCLUSION Based on the review of the licensee's NRC GL-88-01 response the staff concludes that the response-as evaluated is acceptable with the exception of the licensee's '

positions as identified above. The licensee is requested to submit a TS change that would require an ISI statement per GL-88-01 and the staff's GL-88-01 posi-tions with regard to leak detection with the exception that frequency of leakage-monitoring GL-88-01.

may be every eight hours instead of every four hours as required in The-staff also concludes that the proposed IGSCC inspection and mitigation pro-gram will provide reasonable assurance of maintaining the long-term structural  ;

integrity of austenitic stainless steel piping in the LaSalle County Station, Units 1 and 2.

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,. Attachment 3 r

, SALP.1NPUT FACILITY NAME: LaSalle County station, Units 1 and 2

$UMMARY REVIEW Safety Evaluation (SE) of the licensee's program to resolve the IGSCC in Generic Letter 88-01 for BWR piping made of austenitic stainless steel that is 4 inches or larger in nominal. diameter and contains reactor coolant at a temperature above 200 degrees Fahrenheit during power operation regardless of code classification.

The licensee was required to address the following:

1. The current plans regarding pipe replacement and/or other measures taken to mitigate IGSCC and provide assurance of continued long term integrity and reliability.

2. The Inservice Inspection (ISI) Program to be implemented at the next refuel-ing outage for austenitic stainless steel piping covered under the sec,pe of GL-88-01 that: conforms to the the staff positions on inspection schedules, methods and personnel, and sample expansion included in GL-88-01.

3. The Technical Specification change to include a statement in the section on ISI that the ISI Program for pipin be in staff positions on schedule,gmethods covered andbypersonnel, the scope ofsample and this letter will expan-sion included in GL-88-01 (See model BWR Standard Technical Specification enclosedinGL-88-01). It is recognized that the Inservice Inspection and Testing sections may be removed from the Technical Specifications Improvement programs. In this case, this requirement shall remain with the ISI section when it is included in an alternative document.

4. The confirmation of your plans to ensure that the Technical Specifications related to leakage detection will be in conformance with the staff positions on -leak detection included in GL-88-01.

5. The plans to notify the hM in accordance with 10 CFR 50.55a(g) of any flaws identified that do not neet IWB-3500 criteria of Section XI of the Code for continued operation without evaluation or a change found in the condition of the welds previously known to be cra,cked and your evaluation of the flaws

'for continued operation and/or your repair plans.

HARRATIVE DISCUS $10N OF LICENSEE. PERFORMANCE-FUNCTION AREA ENGINEERING.AND TEChhiCAL SUFFORT:

The licensee's responses were submitted according to a schedule consistent with

-that requested by the staff in GL-88-01. The licensee was responsive and has implemented twelve-of thirteen items in GL-88-01. However the licensee did not-addastatementtotheTSonleakagemonitoringandtoincludeastatementonISI as required in GL-88-01.

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