IR 05000336/1985008

Ack Receipt of Informing NRC of Steps Taken to Correct Violations Noted in Insp Rept 50-336/85-08

ML20132E129
Person / Time
Site:	Millstone
Issue date:	06/28/1985
From:	Ebneter S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:	Opeka J NORTHEAST NUCLEAR ENERGY CO.
References
NUDOCS 8507170631
Download: ML20132E129 (2)

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, JUN 2 81985 Docket No. 50-336 License No. DPR-65 Northeast Nuclear Energy Company ATTN: Mr. J. F. Opeka Senior Vice President - Nuclear Engineering and Operations Group P. O. Box 270 Hartford, Connecticut 06141-0270 Gentlemen: Subject: Inspection Report No. 50-336/85-08 This refers to your letter dated May. 28, 1985, in response to our letter dated April 25, 198 Thank you for informing us of the corrective and preventive actions documented in your letter. These actions will be examined during a future inspection of your licensed progra Your cooperation with us is appreciate

Sincerely, Origina1 Signed By: Jacque P. Durr Stewart D. Ebneter, Director Division of Reactor Safety cc: E. J. Mroczka, Vice President, Nuclear Operations W. D. Romberg, Station Superintendent D. O. Nordquist, Manager of Quality Assurance R. T. Laudenat, Manager, Generation Facilities Licensing Gerald Garfield, Isquire Public Document Room (PDR) Local Public Document Room (LPDR) NuclearSafetyI(formationCenter.(NSIC) NRC Resident Inspector State of Connecticut 8507170631 850628 PDR ADOCK 05000336 e PDR OFFICIAL RECORD COPY RL MILLSTONE 2 85-08 - 0001. /19/85 I

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HARTFORD, CONNECTICUT 06141-0270 L L J [[ [ [,",~. (203) 66s-5000 May 23,1935 Docket No. 50-336 A04846 Mr. Stewart D. Ebneter, Director Division of Reactor Safety Region I 631 Park Avenue King of Prussia, Pennsylvania 19406 Reference: (1) Stewart D. Ebneter letter to W. G. Counsil, dated April 25, 198 . Centlemen: Millstone Nuc! car Power Station, Unit No. 2 Inspection No. 50-366/85-03 This report is submitted in reply to Reference (1) which informed the Northeast Nuclear Energy Company of a Notice of Deviation. This was the result of an unfulfilled commitment noticed during an inspection conducted February 19 - March 1,198 . Deviation

 "The licensee submittal dated January 25, 1979 to NRR proposed the use of Appendix III of Section XI,1974 Edition through Winter 1975 Addenda of the ASME Boiler and Pressure Vessel Code for the ultrasonic examination of piping systems. On June 7,1979, NRR approved the use of Appendix Ill, Winter 1975
. Addenda, and on June 25,1979, the licensee acknowledged the NRR approval of use of Appendix Il Appendix III, Winter 1975 Addenda to the ASME B&PV Code,1974 Edition requires that ultrasonic calibration blocks sha!! be made from material (pipe) of the same nominal diameter and nominal wall thickness or pipe schedule as those to be examine Contrary to the above, from September 1930, to the present, reactor coolant system piping welds at Millstone Unit 2 were examined using a flat calibration block number UT-6 which is not of the same nominal diameter and nominal wall thickness or pipe schedule as the piping welds to be examined. The following are examples of welds which were examined using calibration block UT-6:
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Cold Leg, Steam Generator No. 2 to Pump Weld P-12-L-1 and ,

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Cold Leg to Pump 2B Weld P-16-6-3 and Safety Injection Weld BSI-C-2001A, Nozzle to Pipe."

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   -2-Response Corrective steps which have been taken and the results achieved include:

Evaluation and verification that past examinations performed using the flat calibration standard UT-6 were adequat The acoustic properties of calibration standard UT-6 were compared with the acoustic properties of representative components which were inspected using this standard. The sensitivities actually used to perform the examinations were compared to the sensitivities required by the ASME Boiler and Pressure Vessel Code, Section X Attenuation differences between calibration standard UT-6 and the components were measured using back wall echos to establish signal response. With the back wall echo from UT-6 set at 80% full screen height (FSH), the measured echo from the component was approximately 18% to 22% FSH which is a 12 Decibel (Db) difference. The actual examination sensitivity used for the examinations was established using the side drilled holes in calibration standard UT-6. This sensitivity, when adjusted to the required ASME Section XI notch sensitivity, is ISDb more sensitive than required. Thus, the actual examination sensitivity was 6 Db greater (18 Db - 12Db) or twice as sensitive as required by ASME Section XI. In addition, the notch in calibration standard UT-6 is only 2% of base material thickness vice 10% base material thickness allowed by ASME Section X This further increased the flaw detection sensitivity of the actual examinations beyond that required by ASME Section X It is concluded that, although a flat calibration block not meeting ASME Section XI requirements was used for the examination, the examinations performed had more than adequate sensitivity to meet ASME Section XI requirements. Thus all flaws which would have been detectable if all ASME Section XI requirements were met were detectable by the actual examination performe . Corrective steps which will be taken to avoid further deviations are: , A review by the Inservice Inspection /Non-Destructive Examination (ISI/NDE) Group will check all Millstone Unit 2 calibration standards against applicable ASME Section XI and Regulatory Guide requirement The results of this review, and a schedule for completion of required corrective actions, if needed, will be provided by November 30,198 ! Future examinations will be conducted using an existing curved calibration standard, UT-15,in lieu of UT-6. This standard is made of the appropriate material, is acoustically similar to the actual material being inspected, and has curvature in the range of interest. The curvature of UT-15 is for 36" diameter pipe while the piping to be examined is 30" and 42" diamete Relief from exact compliance with ASME Code Section XI requirements will be requested by August 30,193 l

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 ' With the addition of holes and notches to meet ASME Section XI requirements, calibration standard UT-15 is considered technically acceptable for piping examinations. This will be verified prior to the next scheduled examination of 30" and/or 42" pipe by conducting an evaluation similar to that described above for UT-6.

, I In December 1985 Millstone Unit 2 will implement the Inservice Inspection Program for the second 10 year interval. This program will be based on the

1980 Edition, Winter 1981 Addenda of ASME Code Section XI. All calibration standards will be upgraded to this standard prior to the next scheduled August 1986). refueling outage of Millstone Unit 2 (Currently planned for These actions will assure that Northeast Nuclear Energy Company is in full compliance with all applicable non-destructive examination requirements by the next scheduled refueling outag i

i Very truly yours,

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NORTHEAST NUCLEAR ENERGY COMPANY (

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J. F. OpekaJ b " Senior Vice President

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