ML20214P573
| ML20214P573 | |
| Person / Time | |
|---|---|
| Site: | Hatch  |
| Issue date: | 05/26/1987 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20214P570 | List: |
| References | |
| NUDOCS 8706030441 | |
| Download: ML20214P573 (6) | |
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NUCLEAR REGULATORY COMMISSION UNITED STATES l
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT N0.137 TO FACILITY OPERATING LICENSE DPR-57 GEORGIA POWER COMPANY OGLETHORPE POWER CORPORATION MUNICIPAL ELECTRIC AUTFDRITY OF GEORGIA CIIY OF DALTON, GEORGIA EDWIN I. HATCH NUCLEAR PLANT, UNIT 1 DOCKET NO. 50-321 INTRODUCTION In a letter to the Commission dated March 4,1987 (Reference 1), the Georgia Power Company (the licensee) proposed changes to the Technical Specifications for the Edwin I. Hatch Nuclear Plant, Unit 1, Operating License DPR-57, to pemit hydrostatic and leak testing with a non-critical reactor core.
The licensee historically has used nuclear heat for perfoming inservice hydrostatic and leak testing at the Hatch Nuclear Plant.Section XI of the ASME Boiler and Pressure Vessel Code (Table IWB-2500-1) requires"that the Systems Leakage Test be perfomed prior to startup following each refueling outage. The requirements are incorporated by reference as part of the Commission's regulations. The staff's position is that hydrostatic and leak testinn are to be perfomed before the reactor goes critical from a refueling outage.
The licensee stated that the use of non-nuclear heat for the performance of I
hydrostatic and leak testing would necessitate changes to the Technical Specifications (TS) in three areas. The proposed changes are the following:
1.
The first change would provide exception to the operability requirements for the Reactor Core Isolation Cooling (RCIC) system, the High Pressure Coolant Injection (HPCI) system, the automatic depressurization systems (ADS), and the safety / relief valves (S/RV) during perfomance of either hydrostatic or leak tests using non-nuclear means to heat the reactor coolant.
2.
The second change would provide a refinement to TS Figure 3.6-1, providing pressure / temperature limit curves for fluence values expected for 8,10,12,14 and 16 Effective Full Power Years (EFPY) of reactor operation.
3.
The third change would allow either hydrostatic or leak tests to be performed with all control rods inserted at a coolant temperature greater than 212 F, without primary containment integrity.
8706030441 870526 PDR ADOCK 05000321 P
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l 2-4 2.0 EVALUATION Each of the requested changes is evaluated separately.
2.1 Exemption to operability requirements for the RCIC, HPIC, ADS and S/RV systems during hydrostatic and system leakage testing.
- The proposed use of non-nuclear heat for the performance of hydrostatic and leak testing in place of nuclear heating requires the use of recirculation pump operation and a water-solid reactor pressure vessel to achieve necessary temperatures (range 192 to 236 F) and pressures (range 1005 to 1086 psig).
Under the proposed conditions, the lack of steam generation precludes operation of the HPCI and RCIC turbine driven pumps. The licensee's preposal is to add the following note to the TS for the two affected systems:
i "HPCI (RCIC) is not required to be operable for performance of inservice hydrostatic or leak testing, with reactor pressure greater than 150 psig and all control rods inserted."
In a related matter, conduct of the tests at the proposed conditions results in test pressures greater than the lift pressures for the safety / relief valves (S/RVs). The licensee's solution is to gag the S/RVs, which may be allowed by the inclusion of the following note for the S/RVs and automatic depressurization
- y: tem (ADS) in the TS:
"The ADS (Relief / Safety) valves are not required to be operable for the perfomance of inservice hydrostatic or leak testing, with reactor pressure greater than 113 psig and all control rods inserted.".
The current requirements for operability of the aforementioned systems i
when the reactor coolant temperature is greater than 212*F are to ensure the i
capability for makeup of reactor vessel water in'ventory for decay heat removal l
in the event of a small leak with feedwater capability lost and the main condenser not available.
During hydrostatic and leak testing, control rods i
are fully inserted, the decay heat level is low following a refueling outage, and the reactor is maintained at or near cold shutdown conditions.
(The reactor mode switch will be in either the shutdown or refueling position.)
Therefore, the intended function of the systems is not required when the hydrostatic and leak tests are being perfomed. On this basis, the staff concludes that the proposed change to the TS Limiting Conditions for Operation (LCOs) which will eliminate the requirement for system operability during testing when the reactor coolant temperature is in excess of 212*F is acceptable.
2.2 Revise TS Figure 3.6-1 to provide pressure / temperature limit curves for fluence values expected for 8,10,12,14 and 16 EFPY of reactor operation.
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. The licensee proposed to refine Figure 3.6-1, " Pressure Versus Minimum Temperature for Pressure Tests, such as Required by ASME Section XI," to provide pressure / temperature limit curves for fluence values for 8,10,12, 14 and 16 EFPY.
In addition to Figure 3.6-1, Figures 3.6-2, " Pressure Versus Minimum Temperature for Non-Nuclear Heatup/Cooldown and Low Temperature Physics Tests." and 3.6-3, " Pressure Versus Minimum Temperature for Core Critical Operation (Includes 40"F Margin Required by 10 CFR 50, Appendix G)",
curves valid for 16EFPY were reviewed and evaluated.
Our evaluation was documented in a memorandum to Daniel R. Muller from Gus C. Lainas, March 10, 1986 (Reference 2). We concluded that the curves were conservative and met the requirements of 10 CFR 50, Appendix G and H. ASTM E-185, Regulatory Guide 1.99, Revision 1, and Appendix G,Section III of the ASME Boiler and Pressure Vessel Code.
Figure 3.6-1 in the Technical Specifications provides conservative pressure / temperature limits for the perfomance of hydrostatic and pressure tests based on the anticipated fracture toughnes; of the reactor vessel.
Currently the figure contains one curve, which is valid for 16 EFPY, estimated from the damage received by irradiation surveillance specimens after _5.75 EFPY. Since the measured fracture toughness shift in the surveillance plate exceeded the predicted shift of RT
, using the methodology of Regulatory Guide 1.99, Revision 1,byafactoYDdf2.76,thepredicteddamagewas increased by that factor in preparing the 16 EFPY curve.
The Spring 1987 Hatch Unit 1 outage was initiated after approximately 7.12 EFPY of reactor operation. As proposed by the licensee, the refined Figure 3.6-1 consists of a series of curves in 2 EFPY increments from 8 to 16 EFPY operation. The proposed curve for 16 EFPY is the same pressure / temperature curve previously reviewed and evaluated by the staff (Reference 2).
The purpose of adding the series of curves from 8 to 16 EFPY is to eliminate conservatism in the pressure / temperature limits and permit hydrostatic and pressure tests to be performed at lower temperatures, which will require less l
recirculation pump heatup time.
It is planned to use the 8 EFPY curve for the Spring 1987 test.
No change is proposed for Figures 3.6-2 and 3.6-3 in l
the Technical Specifications.
1 The proposed change to Figure 3.6-1 of the Technical Specifications of Hatch Unit 1 is essentially administrative and allows hydrostatic and leak testing l
.to be perfomed with the minimum amount of heat stored in the reactor coolant to meet the reactor vessel nil-ductility requirements. As the pressure / temperature limits meet the requirements of 10 CFR 50, Appendixes G and H. ASTM E185, Regulatory Guide 1.99, Revision 1, and Appendix G.Section III of the ASME Code, we find the proposed change to be acceptable.
2.3 Exception to the requirement to maintain primary system integrity during hydrostatic or leak testing with the reactor coolant greater than 212'F and fuel in the reactor vessel.
g.
The proposed use of non-nuclear heating for the performance of hydrostatic or leak tests involves a non-critical core, water-solid conditions, low ' temperatures and low fuel decay heat values. Under these conditions primary containment integrity is not required since the secondary containment will be operable pursuant to TS 3.7.C.2 and capable of handling any airborne radiation or steam leaks that could occur. Under the proposed test conditions, the potential for failed fuel and subsequent increase in coolant activity above Technical Specification levels will be mitigated and the amount of stored energy in the primary system is small. The potential consequences become those resulting from release of steam to the secondary containment and subsequent use of the Standby Gas Treatment System (SGTS) to limit radioactive releases to the environment. The licensee has proposed the addition of the following note to the TS LCO for Primary Containment Integrity:
" Primary Containment Integrity is not required for perfonnance of inservice hydrostatic or leak testing with reactor coolant temperature greater than 212*F and all control rods inserted."
On the basis of the expected minimal consequences of a potential release under the proposed test conditions, the staff concludes that the proposed addition to the TS LCO for Primary Containment Integrity is acceptable.
ENVIRONMENTAL CONSIDERATIONS The amendment involves a change in use of facility components located within the restricted area as defined in 10 CFR Part 20. 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 exposure. The Comission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there have been no public coments on such finding. Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR Section 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 is'suance of the amendment.
CONCLUSION The Comission made a proposed detennination that the amendment involves no significant hazards consideration which was published in the Federal Register I
(52 FR 9568) on March 25, 1987, and consulted with the state of Georgia. No l
public comments were received, and the state of Georgia did not have any coments.
4 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 en-dangered by operation in the proposed manner, and (2) such activities will be conducted in compliance with the Commission's regulations, and the issuance of the amenoment will not be inimical to the corrinon defense and security or to the health and safety of the public.
Principal Contributors: Michael McCoy Felix Litten Dated:
May 26, 1987 p
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DATED May 26, 1987 AMENDMENT N0. 137TO FACILITY OPERATING LICENSE DPR-57, EDWIN I. HATCH, UNIT 1 DISTRIBUTION: ~~
Docket File NRC PDR Local PDR PRC System PD#II-3 Reading l
M. Duncan L. Crocker l
B. J. Youngblood D. Hagan T. Barnhart (4) l E. Butcher W. Jones ACRS (10)
OGC-Bethesda GPA/PA ARM /LSMB S. Varga G. Lainas J. Partlow E. Jordan M. McCoy F. Litton i
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