ML20246M071
| ML20246M071 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 08/30/1989 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20246M069 | List: |
| References | |
| NUDOCS 8909070086 | |
| Download: ML20246M071 (4) | |
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UNITED STATES
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\\ "i##c 2 NUCLEAR REGULATORY COMMISSION WA SHsNGTON, D. C. 23555
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SAFETY EVALUATION BY T.HE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT H0. 20 TO FACILITY OPEkATING LICtNSE NO. Ni'F-73 DUQUESNE LIGHT COMPANY-OHIO EDISON COMPANT 3.
ECLEVELAND ELECTRIC ILLUMINATING COMPANY THE TOLEDO EDISON CUMPANY 3 CAVER VALLEY POWER STATION, UNIT NO. 2 DOCKET NO. 50-412
_ INTRODUCTION By letter dated June 22, 1989, Duquesne Light Company (the licensee, acting as agent for the atrove utilities) submitted a request to amend the Technical Specific 6tions for Beaver Valley Ur.it 2.
The amendment would increase the maximum river water temperature limit (the ultimate heat sink temperature), and revise several related specifications. Mc have reviewed the licensee's submittal and cur review results follow.
DISCUSSION AND EVALUAlg The ultimate heat sink B.e. the Ohio River) provides a source of cooling water for normal operation, and to dissipate the heat of an c:cident to achieve and mairtein the unit in a sefe shutdown condition. The (urrent design inlet.
I temperature of the service water system (from river water) for Unit 1 is C64 The impact of increasing the river water temperature 1,mit from 86'T to 09'F was evaluated by the liceosee for its effects on safety-related equipment during nomal operation, effects on post-accident containment depressuriration/
cooling, and effects on reactor safe shutdown. The increase in the a'lowable river water temperature will provide additional margin to prevent a piant shutdown shculd abnormally hot weather conditions, as experienced in the summer of 1988, recur.
(1) Figure 3.6-1 and Specifications 3.6.3.4, 3.6.1.5 and 3.7.5.1
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Figure 3.6-1, the maximum allowab'ie Primary Containment Air Pressure versus river water temperature curve, has been revised to reflect the revised
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containment depressurizhtion analysis based on an RWST temperature limit i
and the increased river water temperature limit. The revised figure includes l
additional containment averaga air temperature restrictions when operating with l
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-2 river water temperature above 87 F as required to support the assumptions of the revised analysis.
Technical Specification 3.6.1.4 and 3.6.1.5 for containment maximum air partial pressure and containment minimum' temperature are revised to be consistent with the new Figure 3.6-1.
The licensee used the LOCTIC computer code to perform the reanalysis.
The reanalysis took into account the following changes:
i Use of a maximum RWST temperature (50*F) e.
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Containment quench spray thermal efficiency is assumed to be 99% (95%
was assumed in the licensing basis), and recirculating spray thermal efficiency is assumed to range between 99% and 95% (a constant 90%
wasassumedinthelicensingbasis). These are currently acceptable values.
Service water flow through the recirculation spray heat exchangers c.
was reduced from 12000 gpm to 11000 gpm.
The results of the licensee's analyses show that the Containment Depressurization System is capable of reducing the containment pressure to subatmospheric within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> for river water temperature up to 87*F. Depressurization will still be attained in an hour if river water temperature is at 89'F or less and initial containment temperature at greater than 100*F. Thus no revisions need be made to accident evaluations in the unit's licensing basis.
Furthermore, the reanalysis showed that NPSH requirements will continue to be satisfied for the low head safety injectidn pumps and recirculation spray pumps.
The licensee evaluated the elfcct of elevated service water temperature on other plant systems, such as th? emergency diesel generators cooling system, control room air conditioning units, safeguards area air conditioning units, All of these evaluations lead to the conclusion that the systems are etc.
chpable of accepting the increased river water temperature while continuing to perform their intended design functions.
The licensee evaluated the effect of the increased service water tem>erature on the reactor coolant system's cooldown capability using the residual leat removal systems.
At the elevated temperatures, Unit 2 would require 28 hours3.240741e-4 days <br />0.00778 hours <br />4.62963e-5 weeks <br />1.0654e-5 months <br /> (instead of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />) to cool down from 350*F to 140*F. There is thus a time increase of about 4' hours, but the longer cooling ~ time is still within acceptable 11 mitt.
(i.e. 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> in the Standtra Review Plan).
Based on satisfactory resolution of all the above considerations, we find the increase of service water temperature limits and the associated revised depressurization analysis acceptable.
(2) Bases Sectiont, 3.6.1.4 and 3.6.1.5 1
The bases sections are revised to reflect the above changes. We concur with the bases.
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l ENVIRONMENTAL CONSIDERATION This amendment changes requirements with respect to the installation or use of facility components located within the restricted area as defined in 10 CFR Part 20 and changes surveillance requirements. We have determined that i
the amendiaent involves no significant increase in the amounts, and no signifi-cent change in the types, of any effluents that :nay be relegsed offsite, and that there is no si radiation exposure.gnificant increase in individual or cuculative occupational We have previously issued a proposed finding that these amendments involve no significant hazards consideration and there has been no public comment on such finding. Accordingly, this amendment meets the eligibi-lity criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b') ne environmental impact statement or environmental assessment need be prepared in connection with the issuance of this amende.ent.
CONCLUSION We have evaluated the effects of increasing the allowabla river water temperature on the system and components to perform their safety function, and found the effects to be minor and thus acceptable.
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 menner, and (2) such activities will be conducted in compliar.ce with the Ce.dssion's regulations, and (3) the issuance of this amendment will not be inimical to the corrrnon defense and security or to the health and safety of the public.
Dated: August 30, 1989 Principal Contr_1.butors: Jin Guo and Peter S. Tam
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AMENDHENT NO. 20 TO FACILITY OPERATINS LICENSE NO. NPF-73 DISTRIBUTION 4Occket:F11 erb RRC & 1.ocal PDRs Plant File S.Varga(14E4)
B. Boger (14A2)
J. Stolz S. Norris P. Tam OGC D. Hagan (MNBB 3302)
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B. Grimes 19A2)
.T. Meet (4)(P1-137)
W. Jones (P-130A)
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