ML20236J863
| ML20236J863 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 07/28/1987 |
| From: | NRC |
| To: | |
| Shared Package | |
| ML20236J860 | List: |
| References | |
| NUDOCS 8708060317 | |
| Download: ML20236J863 (3) | |
Text
r UNITED STATES 8"
3 g
NUCLEAR REGULATORY COMMISSION rn
- j WASHINGTON, D. C. 20555
\\...../
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT N0.111 TO FACILITY OPERATING LICENSE NO. DPR-66 DUQUESN'E LIGHT COMPANY OHIO EDISON COMPANY PENNSYLVANIA POWER COMPANY BEAVER VALLEY POWER STATION, UNIT NO. 1 DOCKET NO. 50-334 l
l INTRODUCTION f
I In a letter from J. D. Sieber to the NRC dated February 11, 1987,'the Duquesne Light Company (the licensee), submitted Proposed Operating License Change Request No.120 requesting amendment of Operating License No. DPR-66. The proposed change addresses the Beaver Valley Power Station Unit I reactor vessel pressure-temperature limits. The bases for the proposed.heatup and cooldown limits are the test results from the Beaver Valley Unit.1 surveillance program submitted for. staff review in a letter from J. J. Carey to H. R. Denton dated November 12, 1985. This November 12, 1985 letter 1
contained the Westinghouse Report WCAP-10867, " Analysis of Capsule U from the Duquesne Light Company Beaver Valley Unit 1 Reactor Vessel Radiation Surveillance Program," by R. S. Boggs S. L. Anderson, and W. T. Kaiser, and dated September,1985.
DISCUSSION Pressure-temperature limits must be calculated in accordance with the requirements of Appendix G,10 CFR 50, which became effective on July 26, 1983. Pressure-temperature limits that are calculated in accordance with the requirements of Appendix G,10 CFR 50, are dependent upon the initial reference temperature (RT for the limiting materials in the beltline and closureflangeregionsofEbe)reactorvesselandtheincreaseinRT N
resultingfromneutronirradiationdamagetothelimitingbeltlineNIerial.
The licensee indicated that the initial RT for the limiting materials in theclosureflange.andbeltlineregionsofEkeBeaverValleyUnitIvesselwas N
estimated using the method recommended by the. staff in Branch Technical Position MTEB 5-2, " Fracture Toughness Requirements " which is documented in the Standard Review Plan, Section'5.3.2, " Pressure-Temperature Limits."
The limiting beltline material is the lower shell longitudinal weld which was
. fabricated using weld wire (heat no. 305414) and Linde 1092 flux (lot no. 3947). The licensee indicates that Branch Technical Position MTEB 5-2
!@S Rail!GElk P
o '
results in an initial RT of 0 F for this weld material. The licensee indicates that the limitkbh closure flange region material is the closure head flange or the vessel flange, in which the initial RT is estimated as 60'F.
NDT The increase in RT resulting from neutron irradiation damage depends upon i
thepredictedamoukTof neutron fluence and the rate of embrittlement of the l
limiting reactor vessel beltline material. ThelicenseeestimatedtQtthe2 j
neutron fluence at the inside surface of the vessel will be 1.4 x 10 n/cm at 9.5 effective full power years (EFPY).
EVALUATION The increase in RT resulting from neutron irradiation damage was estimated bythelicenseeachbfdingtoRegulatoryGuide1.99Rev.1,"Effectsof M dual Elements on Predicted Radiation Damage to Reactor Vessel Materials."
Table I compares the observed increase in RT to that predicted according to Regulatory GukO[ of the surveillance weld metal 1.99 Rev. 1.
The surveillance
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weld metal is not from the same heat of flux and wire as that used in the fabrication of the limiting beltline weld. However, it may be used to evaluate the effect of irradiation on the beltline weld because it was fabricated using the same type of flux and wire as the limiting beltline weld. The surveillance material test results indicate that the increase in RT of the surveillance weld metal in Capsule V is predicted to within 3% by Reh0IatoryGuide1.99Rev.1. Also, the surveillance material test results indicate that the increase in RT of the surveillance weld metal in CapsuleUislessthanthatpredkhIedbyRegulatoryGuide1.99Rev.1. Hence, the Regulatory Guide should provide a conservative estimate as to the amount of increase in RT resulting from neutron irradiation for the Beaver Valley UnitIlimitingr$Ntorvesselbeltlineweld.
Comparison of Observed and Calculated Increase in RT NDT of Weld Metal in Surveillance Capsules Increase in RT Surveillance Capsule Increase in RT Calculated UsikT NDT Capsule Fluenge Measured R.G. 1.99 Rev. 1 (n/cm )
( F)
( F) 18 V
2.91 x 10 150 146 18 0
6.54 x 10 155 218 We have used the unirradiated RT for beltline and closure flange materials, whichwerepreviouslydiscussed,NNeneutronfluenceestimatesofthe licensee, the Regulatory Guide 1.99 Rev. I method of estimating neutron irradiation damage, and the Standard Review Plan 5.3.2 method of calculating pressure-temperature limits to evaluate the licensee's proposed pressure-temperature limits. Our evaluation indicates that the proposed 1-
r
. pressure-temperature limits meet the safety margins of Appendix G,10 CFR 50, for a period of time corresponding to 9.5 EFPY Hence, Proposed Change No.120 for Beaver Valley Unit 1 is approved as requested.
]
l ENVIRONMENTAL CONSIDERATION l
This amendment involves a change in the installation or use of a facility component located within the restricted areas as defined in 10 CFR Part 20.
-l The staff has determined that the amendment involves no significant 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 Comission has previously issued a proposed finding that this amendment involves no significant hazards consideration and there has been no public comment on such finding. Accordingly, this amendment meets the eli categorical exclusion set forth in 10 CFR 51.22(c)(gibility criteria for 9).
Pursuant to 10 CFR 51.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance of this amendment.
CONCLUSION We nave 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 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.
PRINCIPAL CONTRIBUTORS:
Samson Lee, Reviewer C. Y. Cheng, Branch Chief Dated:
July 28, 1987 1
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