ML20195B625
| ML20195B625 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 06/10/1988 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20195B598 | List: |
| References | |
| NUDOCS 8806210467 | |
| Download: ML20195B625 (2) | |
Text
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- 8 UNITED STATES t
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N NUCLEAR REGULATORY COMMIS210N WASHINGTON, D. C. 20555 s
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SAFETV EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELAMOTOAMENDMENTNO.
3 TO FACILITY OPERATING LICENSE NO. NPF-73 DUQUESNE LIGHT COMPANY
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9 OHIO EDISON COMPANY THE CLEVELAND ELECTRIC ILLUMIWATING COMPANY-THE TOLED0 EDISON COMPANY" t
BEAVER VALLEY POWER STATION, UNIT NO. 2 DOCKET NO. 50-412
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j' INTRODUCTION
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By letter dated February 11, 1988 DuquesdeLightCompany(actingasagentfor itself and other utilities named above) subnitted a request to amend the Technical Specifications of Beaver Valley Power Stat \\on, Unit 2.
The proposed changes would revise the steam generator water level low-low rcactor tr1p setpoint, and the auxiliary feedwater actuation setpoint.
DISCUSSION AND EVALUATION The amendment revises the steam generator water level low-low reactor trip setpoint in Table 2.2-1, "Reactor Trip System Instrumentation Trip Setpoints". s '
and the steam generator water level low-lowt sxiliary feedwater actuation t('
setpoint in Table 3.3-4, "Engineered Safety Features Act'uation System
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1 Instrumentation Trip Setpoints", from > 15.5% narrow range level span to > gg 11.5% narrow range level span.
This cliange renoves a 4% environmental 4s allowance the was previously added to the sterm generator low-low level setpoint calculation to account for radiatienL ef fects en the steam generator level transmitters. ' The associated values fer "Allovable Value", "Total Allowance", and "z" for these setpoints in Table 2.2-1 and 3.3-4 are also revised accordingly.
The steam generator low-low level reactor trip and auxiljary ferdwater i
actuation protection is assumed in the following accidents as discussed in Section 15.2 of the FSAR:
Loss of External Electrical Load / Turbine Trip Loss of Non-emergency AC Power to the Station Auxiliaries i
Loss of Normal Feedwater Flow j
Feedwater System Pipe Breaks
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None of these four events resulc in fuel failures that would produce accident radiation levels that need to be accounted for by the 4% uncertainty for radiation effects for this instrument channel.
Elimination of the 4%
uncertainty allows the steam generator low-low level setpoint to be reduced as described below.
The Unit 2 reactor trip and engineered safety features setpoints were calculated using standard Westinghouse methodology as presented in Westinghouse Topical Report WCAP-11366 (reviewed by NRC during licensing of the unit). The required setpoints are obtained by adding the specific channel statistical allowance (for channel inaccuracies) to the safety analysis limit. The safety analysis limit for steam generator low-low water level is 0% of narrow range level span e provided in Table 15.0-4 of the FSAR. The channel statistical allowance for the steam generator low-low level protection channel included a 12% environmental allowance of wnich 47 accounted for transmitter radiation effects. Pemoving the 4% uncertainty for radiation effects revises the overall channel statistical allowance for this protection channel from 15.3% to 11.3%.
The revised se:coint of 11.5% still meets the safety analysis limit of Table 15.0-4 of the FSAR, with the required channel accuracies included < 'd a 0.2% additional margin.
The revised setpoints for steam generator level low-low reactor trip and auxiliary feedwater actuation are consistent with the safety limit assumed in the FSAR safety analysis, consistent with approved setpoint methodology, removes an overconservatism which contributes to unnecessary reactor trips and
- SF actuations, and are thus acceptable.
ENVIRONMENTAL CONSIDERATION This amendment changes a requirement with respect to the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The staff has determined that the amendment involves no signif-icant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed t inding that this amendment involves no significant hazards consideration and there has been no public comment on such finding. Accordingly, this mcndment meets the eligibility criteria for categorical exclusion set forth in 10 CTR 51.22(c)(9). Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the iss:ance of this amendment.
CONCLUSION We have concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (2) such activities will be conducted in compliance with the Comission's regulations and the issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public.
Dated:
June 10,1988 Principal Contributor:
P. Tam
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