ML20216G935
| ML20216G935 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 04/15/1998 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20216G925 | List: |
| References | |
| NUDOCS 9804200529 | |
| Download: ML20216G935 (3) | |
Text
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UNITED STATES g
j NUCLEAR REGULATORY COMMISSION 2
WASHINGTON, D.c. SoseH001
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RFt ATED TO AMENDMENT NO.126 TO FACILITY OPERATING LICENSE NO. NPF-57 PHILADELPHIA FI FCTRIC COMPANY LIMERICK GENERATING STATION. UNIT 1 DOCKET NO. 50-352
1.0 INTRODUCTION
la a letter dated January 12,1998, the Philadelphia Electric Company (PECO, the licensee) submitted, for NRC approval, Technical Specification Change Request No. 97-02-1, in accordance with 10 CFR 50.90, requesting changes to the Lime ick Generating Station (LGS),
Unit 1 Technical Specifications (TSs). The proposed changes will revise TS Table 4.4.6.1.31 to i
change the withdrawal schedule for the first capsule to be withdrawn from 10 Effective Full Power Years (EFPY) to 15 EFPY.
In addition, PECO requested, for NRC approval, a revision to TS Surveillance Requirement 4.4.6.1.4. This revision will remove the references to flux wire removal and analysis that was originally required following the first cycle of operation. The referenced flux wires were never located following the first cycle of operation. The proposed TS Surveillance requirement will be changed to refer to the flux wires that are located within the surveillance capsules, which will be removed and analyzed in accordance with the surveillance capsule removal schedule located in TS Table 4.4.6.1.3-1.
2.0 BACKGROUND
The surveillance program for LGS Unit 1 was implemented to monitor the radiation induced changes in the mechanical and impact properties of the pressure vessel materials. The original surveillance program was established in accordance with 10 CFR Part 50, Appendix H, and ASTM E185-73. Case A of ASTM E 185-73 applies to LGS Unit 1, since the vessel has a predicted shift in the reference nil-ductility temperature of less than 100 *F and will be exposed to a neutron fluence of less than 5 x 10 n/cm over the design lifetime of the plant. The original 2
withdrawal schedule specifies the removal of the first and second surveillance capsules at 10 and 30 EFPY, respectively. The surveillance program for LGS Unit 1 also includes a third capsule, which is a spare without a specific withdrawal schedule.
3.0 EVALUATION Appendix H to 10 CFR Part 50, " Reactor Vessel Material Surveillance Program Requirements,"
includes criteria to monitor changes in the fracture toughness properties of ferritic materiais in the reactor vessel beltline region of light water nuclear power reactors which result from exposure of these materials to neutron irradiation and the thermal environment. Appendix H to 10 CFR Part 50 endorses ASTM E185, " Surveillance Tests for Nuclear Reactor Vessels."
9804200529 980415 PDR ADOCK 05000352 P
% l Appendix H states that "the design of the surveillance program and the withdrawal schedule must meet the requirements of the edition of ASTM E185 that is current on the issue date of the ASME Code to which the reactor vessel was purchased." in addition,10 CFR Part 50, Appendix H, states that a proposed withdrawal schedule must be submitted with a technical justification as specified in 10 CFR 50.4, and, that the proposed schedule must be approved prior i
l to implementation.
~
. By ASTM E185-73, it is recommended that the capsules be withdrawn according to application l
by either one of these cases: Case A - where both the predicted increase in transition l
temperature of the reactor vessel steel is 100 *F or less and the calculated peak neutron fluence (E > 1 MeV) of the reactor vessel is 5 x 10 n/cm or less, or Case B - where the predicted 2
increase in transition temperature of the reactor vessel steelis greater than 100 F or where the calculated peak neutron fluence (E > 1 MeV) of the reactor vessel is greater than 5 x 10'8 n/cm,
2 Case A applies to the Limerick Unit 1 surveillance program. Case A of ASTM E185-73 requires the first and second capsules to be withdrawn at a capsule fluence corresponding to the calculated exposure of the reac;0r *ts" et approximately 100 to 125 percent of the reactor design life. The third capsule is to be a stanary capsule.
u In the submittal of January 12,1998, the licensee submitted a proposed withdrawal schedule with a technicaljustification as specified in 10 CFR 50.4. The licensee's justifica. tion for revising the withdrawal schedule for the first capsule from 10 EFPY to 15 EFPY is that, at 10 EFPY, the data may not be useful because the expected shift in RTa is small and may be indistinguishable INm the data scatter that would typically be experienced from the testing of an unirradiated spedmen. The second and third capsules meet the withdrawal requirements of Case A of ASTM E185-T'4, but the first capsule does not. However, withdrawal of the first capsule at 15 EFPYs of operatio.. will provide enough neutron fluence to monitor the amount of radiation embrittlement, in addition, t.f licensee requested, for NRC approval, a revision to TS Surveillance Requirement i
4.4.6.1.4. This avision will remove the references to flux wire removal and analysis that was origirially required following the first cycle of operation. The referenced flux wires were never located following th first cycle of operation. The proposed TS surveillance requirement will be
- changed to refer to the flux wires that are located within the surveillance capsules, which will be j
removed and analyzed in accordance with the surveillance capsule removal schedule located in TS Table 4.4.6.1.3-1. The NRC has determined that the deletion of removal and analysis of flux wires is acceptable because the analysis can be performed using the flux wires in the surveillance capsules.
j 1
4.0
SUMMARY
CONCLUSION 1
Based on our review of the licensee's submittal, we conclude that the licensee has provided an acceptable justification, as specified in 10 CFR 50.4, for the revised withdrawal schedule of the first capsule in the Limerick Unit 1 surveillance program. Section Ill.B.3 of Appendix H indicates that a proposed withdrawal schedule must be approved prior to 'mplementation. Although the i
l
' first capsule does not satisfy the schedule recommendations of ASTM E185-73, its removal at l
15 EFPY is acceptable because it will receive a sufficiant amount of neutron fluence to monitor
I
. l the amount of radiation embnttlement. The second and third capsules meet the recommended withdrawal schedule of ASTM E185-73. Therefore, the staff approves the revised withdrawal sct.edule, as indicated in the TS Change Request No. 97-02-1, for LGS Unit 1. In addition, we find the proposed revision to TS Surveillance Requirement 4.4.6.1.4 acceptable.
5.0 STATE CONSULTATION
in accordance with the Commission's regulations, the Pennsylvania State official was notified of the proposed issuance of the amendment. The State official had no comments.
6.0 ENVIRONMENTAL CONSIDERATION
l The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and changes the surveillance l
requirements. The NRC 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 Commission has previously issued a proposed finding that the smondment involves no significant hazards consideration, and there has bean no public comment on such finding (63 FR 6988). Accordingly, the amendment meets the eligibility criteria fr r categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b) no e
environmentalimpact statement or environmental assessment need be prepared in connection with the issuance of the amendment.
7.0 CONCLUSION
l The Commission has concluded, based on the considerations discussed above, that: (1) there is j
reasonable assurance that the health and safety of the public will not be endangered by l
operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor: M.Khanna Date: April 15, 1998