ML15112B058
| ML15112B058 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 05/17/1982 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML15112B059 | List: |
| References | |
| NUDOCS 8206070128 | |
| Download: ML15112B058 (2) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 EVALUATION OF RELIEF REQUEST FOR THE OCONEE NUCLEAR STATION INSERVICE TESTING PROGRAM B. Piping Pressure Boundary
- 2. Relief Request Relief from outside surface visual examination of core flood nozzle-to safe end and safe end-to-pipe welds is requested for Oconee Units 1, 2 and 3 (Item B4.1, Examination Category B-5).
Code Requirement Volumetric and surface examination shall be performed during each inspection interval and shall cover the circumference of 100% of the welds. The areas examined shall include the base material for at least one wall thickness beyond the edge of the weld.
Licensee Basis for Requesting Relief The subject welds will be inspected by UT and VT from the inside surface. Outside surface visual examination wduld require about 80 man-hours in radiation fields of from 0.5 to 2 R/Hr. The preparation includes removal of the. refueling canal seal plate, shielding bricks and supports in the nozzle area, and insulation.
Due to the elevation and proximity to the reactor vessel cavity temporary shielding is not considered practical.
Licensee Proposed Alternate Examination Welds will be inspected by UT and VT from the inside surface.
Evaluation The licensee has performed and is committed to.perform ultrasonic examination of the core flood nozzle-to-safe end and safe end-to-pipe welds from the inside surface. This examination covers sufficient volume of weld and base metal to'detect unacceptable flaws originating from the outer surface. To perform the required outside surface visual examination on the core flood nozzle-to-safe end and safe end-to-pipe welds would require an effort of preparation and personnel exposure to radiation which far exceed the additional gain in safety of the Oconee Units 1, 2 and 3.
820607012~8 820517 PDR ADOCK 0500026P 0
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-2 The staff finds that imposition of the outside surface visual examination requirement would place an undue burden on the licensee, that the requirement is impractical considering the effort and exposure versus safety gain, and that the ultrasonic examination which will be performed will provide assurance of the structural integrity of the welds and heat affected zones. In addition, the licensee has committed to perform a visual inspection on the inside surface of the affected areas to detect any near surface indications. We, therefore, conclude that relief from the surface examination requirement may be granted.
CONCLUSIONS
- 1. Summary We have reviewed the above relief request and have determined that the Code requirement is impractical and that the relief request 4s authorized by law and will not endanger life or property or the common defense and security and is otherwise in the public interest giving due consideration to the burden upon the licensee that could result if the requirement were imposed on the facility.
- 2. Environmental Consideration We have determined that the granting of relief does not authorize a change in effluent types or total amounts nor an increase in power level and will not result in any significant environmental impact. Having made this determination, we have further concluded that granting relief involves an action which is insignificant from the standpoint of environmental impact and that an environ mental impact statement or negative declaration and environmental impact appraisal need not be prepared in connection with the granting of these reliefs.
- 3. Conclusion We have concluded, based on the considerations discussed above, that:.
(1) granting this relief does not involve a significant increase in the probability or consequences of accidents previously considered, does not involve a significant decrease in a safety margin, and, therefore, does not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (3) the activities authorized by the grant of relief will not be inimical to the common defense and security or to the health and safety of the public.
Dated: May 17, 1982 The following NRC staff personnel contributed to this Evaluation:
P. C. Wagner, G. Johnson.