ML20116E619

Proposed Tech Specs 3/4.4.6 Re Addition of Two Hydroset Curves,Effective for 6.5 & 8.5 Efpy,To Existing Ptol Curves

ML20116E619
Person / Time
Site:	Limerick
Issue date:	08/01/1996
From:	PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:
Shared Package
ML20116E601	List: ML20116E598 ML20116E619
References
NUDOCS 9608060060
Download: ML20116E619 (8)

Text

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ATTACHMENT 1 UMERICK GENERATING STATION UNIT 2 DOCKET NO. 50-353 I 1

LICENSE NO. NPF-85 l l i

l TECHNICAL SPECIFICATIONS CHANGE REQUEST l

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! Supporting information for Changes - 4 Pages 1

" ADDITION OF TWO HYDROTEST CURVES, EFFECTIVE FOR 6.5 AND 8.5 EFPY, TO THE EXISTING PRESSURE-TEMPERATURE OPERATING LIMIT CURVES FOR LGS UNIT 2" l

9608060060 960801

. PDR ADOCK 05000353 P PDR

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l Docket No. 50-353 License No. NPF-85 PECO Energy Company, under Facility Operating License No. NPF-85 for Limerick Generating Station (LGS), Unit 2 requests that the Technical Specifications (TS) contained in Appendix A to the Operating Ucense be amended as proposed herein, to revise TS Section 3/4.4.6 (i.e., Figure 3.4.6.1-1) and its associated TS Basis to reflect the addition of two hydrotest curves, effective for 6.5 and 8.5 Effective Full Power Years (EFPY), to the existing Pressure-Temperature Operating Limit (PTOL) curves for LGS Unit 2.

The proposed change to the TS is shown on the revised TS Figure 3.4.6.1-1 and is indicated by markup on TS Bases page B 3/4 4-5 for LGS Unit 2. The TS page and TS Bases page show:ng the proposed change are contained in Attachment 2.

We request that, if approved, the TS change proposed herein be issued by January 24,1997, and become effective within 30 days of issuance of the amendment.

This TS Change Request provides a discussion and description of the proposed TS change, a safety assessment of the proposed TS change, information supporting a finding of No Significant Hazards Consideration and information supporting an Environmental Assessment.

Discussion and Descriotion of the Prooosed Changg The proposed Technical Specifications (TS) Change Request involves the change of Limerick Generating Station (LGS), linit 2, TS Section 3/4.4.6 (i.e., Figure 3.4.6.1 1) and its associated TS Basis to reflect the addition of two hydrotest curves, effective for 6.5 and 8.5 effective full power years (EFPY), to the existing Pressure-Temperature Operating Limit (PTOL) curves for LGS Unit 2.

All components of the reactor coolant system are designed to withstand the effects of cyclic loads resulting from system pressure and temperature changes. These loads are introduced by heatup and cooldown operations, power transients, and reactor trips. In accordance with Appendix G to 10 CFR 50, the Technical Specifications (TS) limit the pressure and temperature changes during heatup and cooldown within the design assumptions and the stress limits for cyclic operation. These limits are defined by the Pressure-Temperature Operating Limit (PTOL) curve for heatup, cooldown, and inservice leak and hydrostatic testing. Each curve defines an acceptable region fu octmal operation. These curves are used for operational guidance -luring heatup and cooldown maneuvering, when pressure and temperature indications are monitored and compared to the applicable curve to determine that operation is within the allowable region.

ASME Section XI requires that a system leakage test be performed each refueling outage to confirm the integrity of the Reactor Coolant Pressure Boundary. This involves pressurizing the pressure retaining boundary of the reactor coolant system to the normal operating pressure associated with 100% rated reactor power. This pressurization must meet the requirements of TS Figure 3.4.6.1-1 for Minimum

! Reactor Vessel Metal Temperature vs. Reactor Vessel Pressure. Using the current LGS Unit 2 PTOL curve, in order to achieve the required 1045 psig system leakage test pressure, minimum reactor vessel metal temperature must be approximately 1917. Thic,is difficult to achieve since system leakage testing is done during Operational Condition 4 (Cold Shutdown) where average coolant temperature is less than or equal to 2007. To provide adequate margin Detween test coolant temperature and this limit, the system leakage temperature limit is established at 195P. This margin assures that there is sufficient time to depressurize and establish shutdown cooling prior to exceeding 2007. With the small differential temperature between maximum coolant (1957) and minimum vessel metal temperature 1

. 1 Docket No. 50-353 License No. NPF-85 i l i I 1

I (191'F) it is difficult and time consuming to increase metal temperaturesto the required values l necessary to support reactor preFSure V9ssel pressurization.

l The Pressure-Temperaturet, . ss in the LGS Unit 2 TS were establishedin accordance with the requirementsof 10CFR50, Appendix G, to assure that brittle fracture of the RPV is prevented. Part of the l analysis involved in developing the curves was to account for neutron irradiation embrittlement effects in l the core region, or beltline. F egulatory Guide 1.99, Revision 2, was issued to predict the shift in nil-ductility reference temperature (RTNDT) as a function of r,eutron fluence in the beltline region and to develop the PTOL curves for 10 EFPY which are already included in the LGS Unit 2 Technical

Specifications. As calculated in Regulatory Guide 1.99, Revision 2, the Adjusted ReferenceTemperature (ART) is equal to the initial RTNDT plus the change in RTNDT due to the fluence plus a margin term.

General Electric Co. calcuiated the ARTS for predicted fluences at 6.5 and 8.5 EFPY, at rerated

, conditions, at the beltline region, based on Rev. 2 of the Regulatory Guide. The resultant curves permit i a lower temperature requirement for the vessel hydro test following 2R04 and 2R05 compared with the i current 10 EFPY PTOL curve and more closely reflect actual RPV required test conditions at the time when testing will be performed.

4 Therefore, we propose that LGS Unit 2 TS Section 3/4.4.6 (i.e., Figure 3.4.6.1-1) and TS Bases 3/4.4.6 I be revised to reflect the addition of two hydrotest curves for 6.5 and 8.5 EFPY.

1 Safety Assessment  ;

The proposedTS change will revise TS Section 3/4.4.6 (i.e., Figure 3.4.6.1-1) and its associatedTS Basis to reflect the addition of two hydrotest curves effective for 6.5 and 8.5 Effective Full Power Years (EFPY), to the existing Pressure-TemperatureOperating Limit (PTOL) curves for Limerick Generating Station (LGS) Unit 2.

The PTOL curves are not used for accident mitigation, as described in the Updated Final Safety Analysis Report (UFSAR). The proposed changes do not impact the existing PTOL curves for 10 EFPY, currently shown in the TS. They only provide additionalinformation (i.e., two new curves) related to the Reactor Pressure Vessel (RPV) condition for 6.5 and 8.5 EFPY, in order to facilitate hydrostatic testing performed after 2RO4 and 2ROS, respectively. The added curves are establishedin compliance with the previous methodology used to calculate the predicted irradiation effects on vesse! beltline materials as documented in the UFSAR. The Adjusted ReferenceTemperaturesto the initial nil ductility reference temperatures (RTNDT) used to evaluate the pressure / temperature limits for the beltline materials were based on Renulatory Guide 1.99, Revision ? There are no physical changesto the plant being introduced by the added PTOL curves. j information Supportina a Findino of No Sionificant Hazards Consideration We have concluded that the proposed change to the Limerick Generating Station (LGS), Unit 2 Technical Specifications (TS) which will revise TS Section 3/4.4.6, " Pressure / Temperature Limits" (i.e.,

Figure 3.4.6.1-1) and its associated TS Basis to add two new Pressure-TemperatureOperating Limit (PTOL) curves for system Hydrotest for 6.5 and 8.5 Effective Full Power Years (EFPY) does not involve a Significant Hazards Consideration. In support of this determination, an evaluation of each of the three (3) standards set forth in 10 CFR 50.92 is provided below.

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Docket No. 50-353 License No. NPF-85

1. The proposed Technical Specifications (TS) chanae does not involve a sianificant increase in the l orobability or consecuencesof an accident previousiv evaluated.

l The proposed Technical Specification (TS) change includes Pressure-TemperatureOperating i Limit (PTOL) curves which were conservatively generatedin accordance with the fracture toughness requiremr nts of 10CFR50, Appendix G. The Adjusted ReferenceTemperaturesto the initial nil ductility refexnce temperatures (RTNDT) used to evaluate the pressure / temperature limits for the beltline materials were based on Regulatory Guide 1.99, Revision 2. Future analyses of the Reactor Pressure Vessel (RPV) surveillance capsule contents and future revisions to the PTOL curve as required, ensure that the reactor pressure boundary will behave in a non- ,

brittle manner during plant testing, startup, and operation throughout the life of the plant. The

! current schedule for removal of the surveillance specimen 3 from Limerick Generating Station

! (LGS) Unit 2 RPV is during 2R05. The proposed change does not impact the existing PTOL '

l curves for 10 Effective Full Power Years (EFPY), currently shown in the LGS Unit 2 TS. The l proposed change only provides additionalinformation (i.e., two new curves) related to the RPV l condition following 6.5 and 8.5 EFPY, in order to facilitate hydrostatic testing performed after l 2R04 and 2R05, respectively. The added PTOL curves are establishedin compliance with the methodology used to calculate the predicted irradiation effects on vessel beltline materials as l documented in the LGS Updateo Final Safety Analysis Report (UFSAR). There are no physical l changes to the plant being introduced by the added PTOL curves.

I Therefore, the proposed (TS) change does not involve an increase in the probability or j consequencesof an accident previously evaluated. i l

2. The proposed TS chance does not create the possibility of a new or different kind of accident from ar.v accident Dreviously evaluated.

The proposed Technical Specification (TS) change includes Pressure-TemperatureOperating Limit (PTOL) curves which were conservatively generated in accordance with the fracture '

toughnessrequirementsof 10CFR50, Appendix G. The Adjusted ReferenceTemperaturesto the initial n!I ductility reference temperatures (RTND1) used to evaluate the pressure / temperature limits for the beltline materials were based on Regulatory Guide 1.99, Revision 2. The proposed changes do not impact the existing PTOL curves for 10 Effective Full Power Years (EFPY),

currently shown in the TS. They only provide additionalinformation (i.e., two new curves) related to the reactor pressure vessel condition for 6.5 and 8.5 EFPY. in order to facilitate hydrostatic testing performed after 2R04 and 2R05, respectively. The added PTOL curves are establishedin compliance with the previous methodology used to calculate the predicted irradiation effects on vessel beltline materials as documented in the LGS UFSAR. The proposed TS change does not involve any physical changes to safety-related equipment.

Therefore, the proposed TS change does not create the possibility of a new or different kind of

( accident, from any accident previously evaluated.

Docket No. 50-353 License No. NPF-85

3. The proposed TS chanae does not involve a sianificant reduction in a maroin of safety.

The proposed change to Technical Specifications (TS) does not reduce the margin of safety as defined in the Bases for any TS. The added Pressure-TemperatureOperating Limit (PTOL) curves for 6.5 and 8.5 Effective Full Power Years (EFPY) corresponding to 2R04 and 2R05, respectively, have been calculated in accordance with the existing methodology used to calculate the PTOL curves currently existing in the LGS Unit 2 TS (i.e., complying with the

! requiremer'ts of 10CFR50 Appendix G, and Regulatory Guide 1.99, Revision 2) and will mota i closely reflect the actual required reactor pressure vessel condition at the time in which the hydrotest is performed. Therefore,the margin of safety is not affected.

t j Therefore, the proposed TS change does not involve a reduction in a margin of safety, i

{ information Supportina an Environmental Assessment l An environmental assessmentis not required for the change proposed by this TS Change Request

] because the requested change to the Limerick Generating Station (LGS), Unit 2, T3 conforms to the j criteria for " actions eligible for categorical exclusion' as specified in 10 CFR51.22(c)(9). The requested j change will have no impact on the environment. The proposed change does not involve a significant hazards consideration as discussed in the preceding section. The proposed change does not involve a significant change in the types or significant increase in the amounts of any effluents that may be released offsite, in addition, the proposed change does not involve a significant increase in individual or cumulative occupational radiation exposure.

Conclusion The Plant Operations Review Committee and the Nuclear Re'.iew Board have reviewed this proposed change to the Limen;k Generating Station (LGS), Unit 2, TS and have concluded that it does not involve an unreviewed safety question, and will not endangerthe health and safety of the public.

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l ATTACHMENT 2 l

l LIMERICK GENERATING STATEON UNIT 2 l DOCKET NO. 50-353 1

1 LICENSE NO. NPF-85 l l

l TECHNICAL SPECIFICATIONS CHANGE REQUEST !

1 NO. 96-15-2 1

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. LIST OF AFFECTED PAGES j

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! UNU 2 l

3/4 4-20 B 3/4 4-5 t

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em j e.sla.slio l A A' 8 B' C C'

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l 1400 1200 1W l I ,

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I glL  !  !  ! l l l l l O j , A', B', C' - CORE BELTLINE 800 INITIAL RTndt OF 40 F FOR PLATE l j A- SYSTEM HYDROTEST LIMIT WITH FUEL IN VESSEL

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i B - NON-NUCLEAR HEATUP/

COOLDOWN LIMIT I

600 C - NUCLEAR (CORE CRITICAL) l f LIMIT x

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I VESSEL DISCONTINUITY l h LIMITS

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C 400 - CORE BELTLINE W

b CURVES A* ARE VAllD UP TO:

312 P510 EFPY I SHIFT l [ 6.5 41.1*F k j 8.5 48.0 F 200 10 52.7 F

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/ CURVES B' AND C' ARE VALID UP TO 10 EFPY OF OPERATION CURVES A. 8, AND C ARE VAllo l

FOR 1 EFPY OF OPERATION O

0.0 100.0 200.0 300.0 400.0 500.0 MINIMUM REACTOR VESSEL METALTEMPERATURE (*F) ,

1 MINIMUM REACTCR VESSEL METAL TEMPERATURE VS. REACTOR VESSEL PRESSURE FIGURE 3.4.6.1-1 i UMERICK- UNIT 2 3/4 4-20

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. 314CTOR COOLANT SYSTEM '

BASES PRESSURE / TEMPERATURE LIMITS (Continued) j The operating limit curves of Figure 3.4.6.1-1 are derived from the fracture 1 toughness Appendix G. requirements of 10 CFR 50 Appendix G and ASME Code Section III, The curves are based on the RTot and stress intensity factor information for the reactor vessel components. Fracture toughness limits and j

the basis for compliance are more fully discussed in FSAR Chapter .5, Para- ,

i graph 5.3.1.5, " Fracture Toughness."

. RTat. The reactor vessel materials have been tested to determine their initial i The results of these tests are shown in Table B 3/4.4.6-1. Reactor I operation and resultant fast neutron, E greater than 1 MeV, irradiation will cause an increase in the RTer.

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based upon the fluence, nickel content and copper content c' the materialTh

! in question, can be predicted using Bases Figure B 3/4.4.6-1 and the recommenda-tions Vessel of Materials."

RegulatoryThe Guide 1.99, Revision 2, " Radiation Embrittlement of Reactor pressure i^ curves A', B' and C', includes an/ temperature limit curve, Figure 3.4.6.1-1, assumed shift in RTer for the conditions at I 10EFPY.9 areas of The A, B and C limit curves are predicted to be bounding for all

! due to ne the RPV until 1 EFPY when the beltline materials RTer will shift, utron fluence, and the beltline curves will intersect the iion-beltl ine discontinuitvy-v f ,

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The act sbomoe, epsce A c.va.ves we osm Pa.ovios::.r a. (,.5 wh 8.5 EFPY.

i n17t' Tn IU ni ot h wi d oe estabh sned per -

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ically during operation by removing and evaluating, in accordance with 10 CFR 3

Part 50, Appendix H, irradiated reactor vessel flux wire and charpy specimens -

installed near the inside wall of the reactor vessel in the core area. Since i

the neutron spectra at the charpy specimens and vessel inside radius are i

essentially identical, the irradiated charpy specimens can be used with con-i fidence in predicting reactor vessel material transition temperature shift.

! The operating limit curves of Figure 3.4.6.1-1 shall be adjusted, as required, I on the basisGuide Regulatory of the1.99, flux wire and charpy Revision 2. specimen data and recommendations of i ,

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C, andThe C', pressure-temperature and A and A', for-reactor limit lines shown in Figures 3.4.6.1-1, curves criticality and for inservice leak and

. hydrostatic testing have been provided to assure compliance with the minimum temperature requirements of Appendix G to 10 CFR Part 50 for reactor criticality and for inservice leak and hydrostatic testing.

I The number of reactor vessel irradiation surveillance capsules and the frequencies for removing and testing the specimens in these capsules are pro-vided in Table 4.4.6.1.3-1 to assure compliance with the requirements of Appendix H to 10 CFR Part 50.

LIMERICK - UNIT 2 B 3/4 4-5 ..nendment No. 51 FEB 1 61995 a . ._ . - _

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