ML20209D422

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Forwards Response to Util 860623 Comments on NRC Safety Evaluation Re Insp & Repair of Reactor Coolant Piping Sys & Core Spray Spargers During 1985 Outage.Addl Info Requested Re Qualifications of Southern Co Svcs UT Subcontractors
ML20209D422
Person / Time
Site: Hatch Southern Nuclear icon.png
Issue date: 09/05/1986
From: Rivenbark G
Office of Nuclear Reactor Regulation
To: Beckham J
GEORGIA POWER CO.
References
TAC-56540, TAC-60943, NUDOCS 8609090296
Download: ML20209D422 (5)


Text

. i Szptembtr 5, 1986 r~m Docket No.: 50-321 Distribution: .(Doc g ket. File j. ACRS 10 OGC-Bethesda EJordan JPartlow BGrimes NRC & L PDRs SNorris Mr. J. T. Beckham, Jr. GRivenbark Branch Files 0" 112T Vice President-Nuclear Generation WKoo Georgia Power Company P.O. Box 4545 Atlanta, Georgia 30302

Dear Mr. Beckham:

SUBJECT:

COMMENTS REGARDING HATCH UNIT 1 IGSCC INSPECTION AND REPAIR DURING 1985 REFUELING OUTAGE We have reviewed the comments contained in Georgia Power Company's (GPC's)

June 23, 1986 submittal regarding the NRC safety evaluation (SE) relating to inspection and repair of Hatch Unit I reactor coolant piping systems and core spray spargers during 1985 refueling outage. Our response to GPC's comments is provic'ed in the enclosure to this letter. GPC identified one error by the staff in the breakdown of the total number of welds inspected and a typo where weld RWCU-6-)UT-5 was identified as RWCU-6-0VT-50. However, the majority of the commeats provided by GPC result from an interpretation of sections of the SE by GPC which differs with our view.

In our SE, we recommended that GPC submit the core spray sparger test results within two weeks of completion of the testing. The intention of our recommend-ation was to relieve GPC from the burden of submitting a full report if the inspection findings were negative. GPC, as indicated in its response, has opted 4

to submit a full report within 30 days of the completion of the inspection as prescribed by I&E Bulletin 80-13. We have no objection to GPC's preference.

- Based on GPC's comments, we have found it necessary to obtain clarification regarding the qualifications of the SCS's UT subcontractors. The additional information identified in the enclosure is necessary to enable us to assess our SE finding regarding the qualifications of the SCS UT subcontractors.

Please provide this additional information so that we can complete our review and reissue the subject SE.

The reporting and/or recordkeeping requirements of this letter affect fewer than ten respondents; therefore, CMB clearance is not required under P.L.96-511.

Sincerely,psd L v m. of N

George W. Rivenbark, Project Manager BWR Project Directorate #2 Division of BWR Licensing

Enclosure:

As stated cc w/ enclosure:

See next page BWR#2 BWR#h BWR#

SN6? s GRivehbark;eh D 14 9/ /86 /86 8609090296 860905

}/(/86 PDR ADOCK 05000321

% PDR

/

Mr. J. T. Beckham, Jr. Edwin I. Hatch Nuclear Plant, i Georgia Power Company Units Nos. I and 2 cc:

BruceW.Chkchill Esquire Shaw,Pittman,PotIs&Trowbridge

! 1800 M Street, N.W.

Washington, D.C. 20036 Mr. L'. T. Gucwa Engineering Department Georgia Power Company P. O. Box 4545 Atlanta, Georgia 30302 -

~

Mr. H. C. Nix, Jr., General Manager Edwin I. Hatch Nuclear Plant Georgia Power Company P. O. Box 442 Baxley, Georgia 31513 Mr. Louis B. Long i Southern Company Services, Inc. ..

P. O. Box 2625 j Birmingham, Alabama 35202 Resident inspector

, U.S. Nuclear Regulatory Comission Route 1, P. O. Box 279

Baxley, Georgia 31513 i

! Regional Administrator, Region II U.S. Nuclear Regulatory Comission,

101 Marietta Street, Suite 3100 Atlanta, Georiga 30303 Mr. Charles H. Badger Office of Planning and Budget Room 610 270 Washington Street 5.W.

Atlanta, Georgia 30334 Mr. J. Leonard Ledbetter, Comissioner Department of Natural Resources 270 Washington Street, N.W.

Atlanta, Georgia 30334 Chaiman Appling County Comissioners County Courthouse Baxley, Georgie 31513

f[ UNITED STATES g p, NUCLEAR REGULATORY COMMISSION D 1 j WASHINGTON, D. C. 20555 6.

RESPONSE TO GPC'S COMMENTS TO NRC SAFETY EVALUATION REGARDING HATCH UNIT 1 IGSCC INSPECTION AND REPAIR DURING 1985 REFUELING OUTAGE SECTION 1.0 (Paragraph 1) The total number (143) of inspected welds stated in the introductory section of our Safety Evaluation is the correct total. The breakdown of the inspected welds in the Recirculation, RHR and RWCU piping systems should be 110, 12 and 21 welds.

(Paragraph 2) We don't agree with the comments, because we specifically addressed welds that eit:.er were free of discontinuities or were with indications and not repaired. We do not consider the four IHSI treated welds subsequently requiring an overlay repair as germane.

SECTION 1.1 We consider the comment regarding the discussion of examiner personnel to perhaps raise a question as to the qualification of the subcontractor UT examiners. Our interpretation of the March 10, 1986 submittal was that all Level II and Level III examination personnel were performing examinations for detection and/or evaluation using Southern Company Services (SCS) qualified procedures. Further, the inspection personnel (Level II and III) were requalified as required at the EPRI NDE Center. Therefore, our interpretation of personnel qualification were essentially SCS personnel irrespective of whether they were actually SCS employees or contractors. We request that Georgia Power Company (GPC) provide the following information so that we can assess our previous finding:

(1) Who were the contractors and what examinations were performed by each for r

SCS?

I (2) Provide the procedures used by each contractor to qualify for IGSCC detection and/or evaluation at the NDE Center.

(3) Provide a comparison of the contractor qualification procedures with those used for the examinations at Hatch I during the 1985 refueling j outage.

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SECTION 1.2 Our SE accurately reports the number of additional welds (20) that were identified as cracked from the current inspection results. The two additional welds in the Recirculation system were a part of the four welds identified by GPC as cracked during the previous outage. Our SE discusses these welds in the following paragraph. The welds were dispositioned as described in Table 5-2 of Revision 2 of SIA report.

The lamination in safe-end to nozzle weld 12BR-C-5 was grouped with the other indications since this indication as well as the others need to be inspected at the next refueling. The SE states this indication was identified as a lamination.

"Both circumferential and axial cracks were observed in the cracked welds" does not mean all welds were cracked both axially and circumferential1y.

Weld RWCU-6-0UT-5 was misidentified as RWCO-6-00T-50.

Section 1.2 of the staff SE simply is a statement of inspection results.

Through wall axial flaws were reported following IHSI for weld 12BR-B-3.

Further, circumferential flaws were reported pre-IHSI by the licensee and not following IHSI. The staff did not address the mechanisms that could have accounted for these unusual inspection results reported by the licensee since the weld was overlayed. We should like to point out that GPC did not provide a discussion of these rather unusual inspection results nor did it speculate on their cause as a part of its earlier submittals.

The staff realized that RHR weld 24B-R-12 had a lack of fusion indication in the overlay. The overlay was not addressed in the SE since the weld itself was unflawed. We believe the licensee's documentation of the discontinuity is sufficient to ensure the defect will be considered in future inspections.

SECTION 1.4 The differences in the inspection results were discussed in Section 1.2.

Section 1.4 of the SE discusses flaw evaluation. GPC's contractor's report of April, 1986 identified that 21 flawed welds were evaluated. This is consistent with our SE.

We should like to point out that GPC's final report from SIA was late. The final report was due to staff on March 25, 1985. The Revision 0 report was incomplete and identified that 20 welds were evaluated. Evaluation of the additional weld (208-D-4) was discussed at the March 18, 1986 meeting but not documented for the record until the May 2, 1986 submittal. The staff issued its SE on April 24, 1986 to support Hatch Unit 1 restart.

SECTION 2.2 This SE section addressed welds that were not overlayed. The SE states that welds received a heat treatment to mitigate crack growth. It also points out that 3 of the 12 welds do not meet staff criteria for IHSI credit in flaw evaluation. It is the current staff position that welds with flaws are approved for one cycle of operation and reinspection and evaluation is necessary to determine the fitness of the welds for continued service. The staff rejects the statement that, "...IHSI of the subject welds constituted their repair."

The IHSI, or any other stress improvement method, is considered a means to inhibit crack initiation, or to mitigate welds with minor cracks, but not a repair.

SECTION 2.3 The specifics of the overlay repairs are discussed in Section 1.4 of the SE.

The fact that one overlay was to facilitate inspection is contained in Section 1.4.

SECTION 2.4 The staff recommendation on air bubble testing was a recommendation not a requirement. The staff intended the submission of inspection test results for cases where no further degradation of the spargers was observed as a relaxation. We were suggesting submittal of the test results in lieu of a formal report for this case. We have no objection to a formal report in accordance with IEB 80-13 thirty days following the inspection.

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