ML20027C890
| ML20027C890 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 10/13/1982 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20027C888 | List: |
| References | |
| NUDOCS 8210270386 | |
| Download: ML20027C890 (6) | |
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UNITED STATES 8
NUCLEAR REGULATORY COMMISSION o
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WASHINGTON, D. C. 20656
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO.46 TO FACILITY OPERATING LICENSE NO. NPF-3 TOLEDO EDISON COMPANY AND CLEVELAND ELECTRIC ILLUMINATING COMPANY DAVIS-BESSE NUCLEAR POWER STATION, UNIT 1 DOCKET NO. 50-346 1.0 Introduction
-. By telephon'ed request on September 16, 1982, followed by a telecopied application September 17, 1982, as confimed by fomal application dated Septerber 30, 1982, Toledo Edison Company (the. licensee) requested a change to Table 4.3-11 of the Appendix A Technical Specifications (TSs) appended to Facility Operating License No. NPF-3 for the Davis-Besse Nuclear Power Station, Unit No.1.
The change would add the following one-time note to Table 4.3-11.
+ The surveillance period for Steam Line Pressure-Low, instrument is extended to 2400 hours0.0278 days <br />0.667 hours <br />0.00397 weeks <br />9.132e-4 months <br />, September 16, 1982.
The TSs would be further amended by adding the synbol, +, in the column headed " Channel Functional Test" for Functional Unit 1.a., Table 4.3-11.
2.0 Background
TS Section 4.3.2.2.1 requires that each Steam and Feedwater Rupture Control System (SFRCS) instrumentation channel be demonstrated operable by the performance of channel checks, channel calibrations, and channel functional tests during Modes 1, 2 and 3 at the frequencies shown in Table 4.3-11.
Table 4.3-11 requires that the instrument channel functional tests shall be conducted monthly. TS Section 4.0.2 specifies that the Surveillance Requirement is to be perfomed within the specified interval with a maximum allowable extension not to exceed 25% of the surveillance interval.
The licensee had last performed the channel functional tests for certain SFRCS Steam Line Pmssure-Lw switches on August 5,1982; thus, the surveil-lance period, including the 25% time extension permitted by TS Section 4.0.2, expired at 2400 hours0.0278 days <br />0.667 hours <br />0.00397 weeks <br />9.132e-4 months <br /> September 12, 1982. The licensee continued operation beyond the expiration of the surveillance interval unaware of the expiration until tne afternoon of Se 16, 1982. At that time, the plant entered Action Statement 3.3.2.2(ptemberb) which would have the effect of requiring plant J
shutdown within one hour. The licensee requested the extension of the sur-I-
veillance period to 2400 hours0.0278 days <br />0.667 hours <br />0.00397 weeks <br />9.132e-4 months <br /> on September 16, 1982, to avoid an unnecessary transient on the unit due to rapid shutdown. This extension period would be adequate for the licensee to complete the mquired channel functional tests.
8210270386 821013 PDR ADOCK 05000346 L
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3.0 Eval uation Davis-Besse exceeded the surveillance test period on the SFRCS steam line low pressure switches. The TSs require that the switches be tested on a monthly basis with a 25% time allowance. The licensee had exceeded the TS surveil-lance interval since midnight of Septerber 12, 1952 However, we were infonned mid-day September 16, 1982.
Past history of the switches has shown no tendency for instrument drift such that there is currently no technical reason to suspect that the switches ara inoperable. The switches have been recently calibrated during the last refueling outage. A strict interpretation of the TSs currently requires a rapid shutdown. Davis-Besse is presently operating at about 75% of rated power. To avoid an unnecessary transient on the unit due to a shutdown, j
the licensee proposes to extend the surveillance period to extend the time i
limit to 2400 hours0.0278 days <br />0.667 hours <br />0.00397 weeks <br />9.132e-4 months <br /> on September 16, 1982. The safety function of these 1
. pressure switches is to provide a steam pressure input to the SFRCS indi-cating a rupture in the main steam system. The SFRCS is c'omposed of two actuation trains each of which will isolate both main steam lines and J
associated feedwater lines upon the detection of a rupture in either main
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steam line.
Each SFRCS actuation train will also initiate one train of auxiliary feedwater and isolate one steam generator. One of the two actua-tion trains has been completely and satisfactorily tested.
Each train picks up pressure indicatiens from both steam lines. Therefore, the plant pre-sently has the ability to sense loss of steam pressure and provide subse-quent protective actions as described above assuming no failures occur in the tested train prior to completing the required surveillance. We there-fore agree with the licensee's analysis that the granting of this TS change is justified.
4.0 Environmental Consideration We have determined that the amendment 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 the amendment involves an action which is insignificant from the standpoint of environmental impact and, pursuant to 10 CFR 551.5(d)(4), that an environmental impact statement, or negative declaration and environ-mental impact appraisal need not be prepared in connection with the issuance of this amendment.
5.0 Conclusion We have concluded, based on the considerations discussed above, that:
(1) because the amendment does not involve a significant increase in the probability or consequences of an accident previously evaluated, y
does not create the possibility of an accident of a type different from any evaluated previously, and does not involve a significant
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DB-1 reduction in a margin of safety, the amendment does not involve a significant hazards consideration, (2) there is reasonable assurance g
that the health and safety of the public will not be endangered by
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operation in the proposed manner, and (3) such activities will be conducted in compliance with the Commission'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.
Da ted: October 13, 1982
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The following tiP.C personne1 have contributed to this Safety Evaluation:
A. W. De Agazio.
W ese 1
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