ML13333A502
| ML13333A502 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 02/14/1980 |
| From: | Baskin K Southern California Edison Co |
| To: | Ziemann D Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8002260628 | |
| Download: ML13333A502 (3) | |
Text
Southern California Edison Company P. 0.
BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD. CALIFORNIA 91770 K. P. BASKIN TELEPHONE MANAGER, NUCLEAR ENGINEERING (213) 572-1401 AND LICENSING February 14, 1980 Director, Office of Nuclear Reactor Regulation Attention:
Mr. D. L. Ziemann, Chief Operating Reactors Branch #2 Division of Operating Reactors U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Gentlemen:
Subject:
Docket No. 50-206 San Onofre Nuclear Generating Station Unit 1 By letter dated September 4, 1979, we requested relief from certain specific Inservice Inspection Program requirements of ASME Boiler and Pressure Vessel Code (B&PVC),Section XI, as invoked by 10CFR 50.55a(g).
By letter dated September 26, 1979, you granted relief for each of the items contained in our September 4, 1979, letter subject to certain alternate requirements'discussed in the Safety Evaluation accompanying your letter.
The purpose of this letter is to (1) clarify one of our relief requests, and (2) indicate several typographical errors in the NRC Safety Evaluation which could affect the substance of the relief which was granted.
Each of these subjects is discussed below:
- 1.
Our September 4, 1979, letter contained the following relief request from the requirements of the 1974 Edition of the ASME B&PVC Section XI, Addenda through Summer 1975:
"Relief Request and Proposed Alternative Relief is requested from the repair requirements of Articles IWA-4000 and IWB-4000.
Repairs will be conducted in accordance with Article IWA-4000 of the 1977 Edition and Addenda through Summer 1978 of Section XI.
-2 Code Requirements The repair requirements are contained in Articles IWA-4000 and IWB-4000. In some cases the rules of ASME B&PVC Section III are invoked. In the event repairs not addressed in these articles are required, the repairs may be made in accordance with the requirements of the original construction code.
Basis for Relief Request The repair rules of the 1974 Edition and addenda through Summer 1975 are ambiguous and lack definition. These rules do not sufficiently define such items as:
pressure testing requirements following repairs by welding, the role of the Authorized Inspector in the repair program, and welder qualifications. These rules do not take into consideration the causes of failure and the suitability of the welding repair procedures. These rules were not developed for plants, like San Onofre Unit 1, which were designed per codes other than Section III of the ASME B&PVC.
In contrast, the repair rules of the 1977 Edition and Addenda through Summer 1978 define in detail:
pressure testing requirements, notification of an Authorized Inspection Agency, and welder qualification records. These rules have provisions for incorporating original design requirements and construction codes. The use of Section III of the ASME B&PVC is explained. Finally, the rules require a complete repair program including evaluation of failure causes and the suitability of repair procedures. This recent code presents clear well-defined repair requirements which meet the intent of the 1974Editipn and Addenda through Summer 1975."
Your September 26, 1979, letter granted this relief with the exception that piping, pump, and valve repairs that do not penetrate through the pressure boundary must be hydrostatically tested. On November 1, 1979, 10CFR50.55a was revised to allow the use of the 1977 Edition and Addenda through Summer 1978 without this exception.
In addition, the NRC Safety Evaluation of our relief request indicates that the repair rules of the 1977 Edition and Addenda through Summer 1978 are significantly improved when compared to those of the 1974 Edition and Addenda through Summer 1975. Therefore, imposition of the exception discussed above is not warranted.
The relief request from the repair requirements of the 1974 Edition and Addenda through Summer 1975 contained in Articles IWA-4000 and IWB-4000 discussed above was intended to include Class 1, 2, and 3 Components. However, we did not reference IWC-4000 (Class 2 Components) and IWD-4000 (Class 3 Components) since these sections merely referred back to IWB-4000 in this Edition of the Code.
Therefore, relief was granted only for Class 1 Components and was not granted for Class 2 and Class 3 Components. Our "Relief Request and Proposed Alternative" as described above should be revised to read:
-3 "Relief is requested from the repair requirements of Articles IWA-4000, IWB-4000, IWC-4000, and IWD-4000 of the 1974 Edition and Addenda through Summer 1975.
Repairs will be conducted in accordance with Articles IWA-4000, IWB-4000, IWC-4000, and IWD-4000 of the 1977 Edition and Addenda through Summer 1978 of Section XI."
It is respectfully requested that the NRC review the clarification provided above and take appropriate action with respect to approving our relief request (1) without imposing the exception to perform a hydrostatic test for piping, pump and valve repairs that do not penetrate through the pressure boundary, and (2) to include relief from repair requirements for Class 2 and Class 3 Components as well as Class 1 Components. The clarification discussed above has been discussed with members of your staff.
- 2.
Typographical errors in the NRC Safety Evaluation which could affect the substance of the relief which was granted are as follows:
- a. Item A.9 on page 8 should be revised from:
"Request relief from volumetric examination of reactor coolant pump casing welds, designated as A-1, 2, and 3, B-5.6, and...
to:
"Request relief from volumetric examination of reactor coolant pump casing welds, designated as A-1, 2 and 3, B-1, 2, and 3 and C-1, 2, and 3, B-5.6, and...
- b. Item C on page 11 contains two references to 25% DAC in the "Evaluation" section which should be corrected to 20% DAC.
We are currently scheduled to shut down for refueling to perform in-service inspection in April, 1980. Accordingly, your action relative to the clarification discussed above should be taken as soon as possible so that we can incorporate these provisions into our program.
If you have any questions or require additional information concerning this matter, please contact me.
Very truly yours, cc: Director, Office of Inspection and Enforcement Region V