ML17258A993
| ML17258A993 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 04/17/1981 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML17258A992 | List: |
| References | |
| NUDOCS 8104300529 | |
| Download: ML17258A993 (2) | |
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UNITED STATES NUCLEAR REGULATORY COMMISSlON WASHINGTON, D. C. 20555 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO. 40 TO PROVISIONAL OPERATING LICENSE NO. DPR-18 ROCHESTER GAS AND ELECTRIC CORPORATION R.
E.
GINNA NUCLEAR POWER PLANT DOCKET NO. 50-244
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The NRC staff has conducted a review of the Licensee Event Reports (LERs) and Technical Specification requirements related to the Control Rod Position Indication Systems (RPI) at Westinghouse PWRs and deter-mined that a wide variation exists in the number of LERs received and the Technical Specification requirements.
2.0 Discussion and Evaluation Westinghouse has performed safety analyses for control rod misalignment up to 15 inches or 24 steps (one step equals 5/8 inch).
Since analysis of misalignments in excess of this amount have not been submitted, we have imposed an LCO restricting continued operation with a misalign-ment in excess of 15 inches.
Because the analog control rod position indication system has an uncertainty of 7.5 inches (12 steps),
when an indicated deviation of 12 steps exists, the actual misalignment may be 15 inches.
This is because one of the coils, spaced at 3.75 inches, may be failed without the operator's knowledge.
The Standard Technical Specifications were written to eliminate any confusion about this, and restrict deviations to 12 indicated steps.
Surveillance requi rements, on the indicat'ion accuracy of 12 steps, were also prepared to ensure that the 15 inch LCO is met.
Since there is no difference intended in requirements issued for any Westinghouse
- reactor, plants with Tech-nical Specifications written in different terms of misalignment should consider the 12 step instrument inaccuracy when monitoring rod position.
A related problem is that the installed analog control rod position indicating system equipment may not, in some areas, be adequate to
'aintain the control rod misalignment specification, requirement because of drift problems in the calibration curves.
This is evidenced by numerous LERs concerning rod position indication accuracy.
In these
- cases, the uncertainty may be more than 12 steps.
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3.0 Rochester Gas and Electric Corporation (RG&E) was requested, by letter dated November 5, 1979, to review the technical specifications for the R.
E. Ginna Nuclear Power Plant to ensure that the control rods are required to be maintained within + 12 steps indicated position and that the rod position indication system is accurate to within + 12 steps.
By letter notarized August 29, 1980 (transmitted September 3, 1980),
RGLE responded to the NRC request and provided proposed technical specification changes to incorporate the staff's requirements.
Based on our review of the licensee's submittal, we find that the proposed changes are in conformance with the staff's request and are, therefore, acceptable.
ENVIRONMENTAL CONSIDERATION We have determined that the proposed amendment does not authorize a
change in effluent types, increase in total amounts of effluents, or an increase in power level, and will not result in any significant environmental impact.
Haying made this determination,'we have concluded
. that the amendment involves an action which is insignificant from the standpoint of environmental impact, and, pursuant to 10 CFR 51.5(d)(4),
that an environmental impact statement or negative declaration and environmental impact appraisal need not be prepared in connection with the issuance of this amendment.
4.0 CONCLUSION
We also conclude, based on the considerations discussed above, that:
(1) because the amendment does not involve a significant increase in the probability or consequences of accidents previously considered and does not involve a significant decrease in a safety margin, the amendment 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) such activities will be conducted in compliance wi'th the Commission's regulations and the issuance of this amendment willnot be inimical to the common defense and security or the health and safety of the public.
Date:
April 17, 1981