ML060180281

Supplement to Proposed Revision to Technical Specifications Reactor Coolant System Heatup/Cooldown Limits (LBDCR 05-MP2-003)

ML060180281
Person / Time
Site:	Millstone
Issue date:	01/11/2006
From:	Hartz L Dominion Nuclear Connecticut
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
05-307A
Download: ML060180281 (56)

Text

Dominion Nuclear Connecticut, Inc.

5000 Dominion Boulevard, Glen Allen, Virginia 23060 Dominiou n

Web Address: www.dom.com January 11, 2006 U. S. Nuclear Regulatory Commission Serial No.

05-307A Attention: Document Control Desk NLOS/PRW Rev. 0 One White Flint North Docket No.

50-336 11555 Rockville Pike License No. DPR-65 Rockville, MD 20852-2738 DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2 SUPPLEMENT TO PROPOSED REVISION TO TECHNICAL SPECIFICATIONS REACTOR COOLANT SYSTEM HEATUP/COOLDOWN LIMITS(LBDCR 05-MP2-003)

In a letter dated July 14, 2005, Dominion Nuclear Connecticut, Inc. (DNC) requested to amend Operating License DPR-65 for Millstone Power Station Unit 2 (MPS2).

The proposed license amendment requested to revise the MPS2 technical specifications to modify the reactor coolant system (RCS) heatup and cooldown limits.

In a facsimile dated October 25, 2005, the NRC staff requested additional information (RAI) to facilitate the technical review being conducted.

In a conference call on November 28, 2005, DNC provided responses to the NRC's RAI.

Accordingly, supplements DNC's initial request regarding the MPS2 heatup/cooldown limits.

While preparing this response, an incorrect application of the newer version of the ASME Code being used was noted to have occurred in an internal DNC calculation supporting the information contained in LBDCR 05-MP2-003.

The application was related to the temperature variable used to calculate Kic. This incorrect application of the Code was only related to the calculation supporting the proposed license amendment request. No inconsistencies have been found relating to calculations supporting current licensing bases. The application affected Attachment 1 of the DNC submittal dated July 14, 2005, which contained the description of the proposed license amendment.

Consequently,, which contains the technical specification (TS) marked-up pages,, which contains the retyped pages, and Attachment 4, which contains the marked-up pages of the TS bases were also affected. of this letter provides replacements to the attachments of the July 14, 2005 submittal in their entirety.

The additional information provided in this letter does not affect the conclusions of the safety summary and significant hazards considerations discussion in the DNC letter dated July 14, 2005.

There are no commitments contained in this letter.

Serial No. 307A Docket No.

50-336 Supplement: RCS Heatup/Cooldown Limits Page 2 of 4 Should you have any questions regarding the supplemental information provided, please contact Mr. Paul R. Willoughby at (804) 273-3572.

Very truly yours, Leslie N. Hart Vice President - Nuclear Engineering

Enclosures:

(2)

Serial No. 307A Docket No.

50-336 Supplement: RCS Heatup/Cooldown Limits Page 3of4 cc:

U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406-1415 Mr. V. Nerses Senior Project Manager U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Mail Stop 8C2 Rockville, MD 20852-2738 Mr. S. M. Schneider NRC Senior Resident Inspector Millstone Power Station Director Bureau of Air Management Monitoring and Radiation Division Department of Environmental Protection 79 Elm Street Hartford, CT 06106-5127

Serial No. 307A Docket No.

50-336 Supplement: RCS Heatup/Cooldown Limits Page 4 of 4 COMMONWEALTH OF VIRGINIA

)

)

COUNTY OF HENRICO

)

The foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by Leslie N. Hartz, who is Vice President - Nuclear Engineering, of Dominion Nuclear Connecticut, Inc. She has affirmed before me that she is duly authorized to execute and file the foregoing document in behalf of that Company, and that the statements in the document are true to the best of her knowledge and belief.

Acknowledged before me this ILL day of 94 2006.

My Commission Expires:

Ar By Notary Public (SEAL)

Serial No. 307A Docket No.

50-336 ENCLOSURE 1 SUPPLEMENT TO PROPOSED REVISION TO TECHNICAL SPECIFICATIONS (LBDCR 05-MP2-003) REACTOR COOLANT SYSTEM HEATUP/COOLDOWN LIMITS DOMINION NUCLEAR CONNECTICUT. INC.

MILLSTONE POWER STATION UNIT 2

Serial No. 307A Docket No.

50-336 Supplement: RCS Heatup/Cooldown Umits Page 1 of 3 SUPPLEMENT TO PROPOSED REVISION TO TECHNICAL SPECIFICATIONS (LBDCR 05-MP2-003) REACTOR COOLANT SYSTEM HEATUP/COOLDOWN LIMITS By letter dated July 14, 2005, Dominion Nuclear Connecticut, Inc. (DNC or the licensee) submitted a license amendment request for a change to the Millstone Power Station, Unit No. 2 (MPS2) Technical Specifications (TS) regarding pressure-temperature (P-T) limits.

The TS change replaces the current P-T limits for 20 effective full-power years (EFPYs) with the proposed P-T limits for 54 EFPYs. The Nuclear Regulatory Commission (NRC) staff requests the following additional information to complete its review.

NRC Reauested Information 1.

The submittal contains very little information in the proposed Bases for TS Section 3/4.4.9, "Pressure/temperatures." However, the NRC staff is able to reproduce the adjusted reference temperature (ART) of 175 0F at one-quarter of the reactor pressure vessel (RPV) wall thickness (1/4T) for the limiting beltline material, Plate C-506-1, using the materials and fluence information from the license renewal application (LRA) for MPS2.

The results from the NRC staff's independent calculation indicate that the licensee did not consider the NRC staff's position established in the safety evaluation (SE) dated August 1, 2005, for the LRA for MPS2 regarding the licensee's calculated fluence values. In that SE, the NRC staff applied a factor of 1.4 to the licensee's reported fluence values because the licensee's fluence calculation methodology is not in accordance with Regulatory Guide 1.190, "Calculational and Dosimetry Methods for Determining Pressure Vessel Neutron Fluence." Please revise the applicable EFPYs for the proposed P-T limits, or revise the proposed P-T limits for 54 EFPYs to reflect the NRC staff's position on the calculated fluence values.

DNC Resionse 1.

The fluence values used to calculate the proposed 54 EFPY P-T limits are documented in WCAP-16012, Rev. 0, "Analysis of Capsule W-83 from the Dominion Nuclear Connecticut Millstone Unit 2 Reactor Vessel Surveillance Program," February 2003. WCAP-16012, Rev. 0 was submitted to the Nuclear Regulatory Commission (NRC) by a letter titled "Millstone Nuclear Power Station, Unit No. 2 Submittal of Third Reactor Vessel Surveillance Capsule Report" dated February 26, 2003. This report provided relevant information for use in revising the P-T limits. The neutron transport and dosimetry evaluation methodologies used in the above WCAP follow the guidance and meet the requirements of RG 1.190 (see page 6-1 of WCAP-16012, Rev 0.)

The use of WCAP-16012 is outlined in the TS change submittal in Appendix A, Section 3.1. Additionally, the methods used to develop the calculated reactor pressure vessel fluence are consistent with the NRC approved methodology described in WCAP-14040-NP-A

Serial No. 307A Docket No.

50-336 Supplement: RCS Heatup/Cooldown Limits Page 2 of 3 "Methodology Used to Develop Cold Overpressure Mitigation System Setpoints and RCS Heatup and Cooldown Limit Curves," January 1996. The use of fluence values developed in accordance with RG 1.190 is consistent with license renewal commitment Item No. 37 for MPS2 as listed in Appendix A of the safety evaluation.

Because the fluence values used to develop the 54 EFPY proposed P-T limits are developed in accordance with RG 1.190, it is no longer necessary to apply the factor of 1.4 as specified for use with fluence values not developed in accordance with RG 1.190.

NRC Reauested Information

2.

(a)

Please identify the limiting material for the heatup curves and provide its ART value at the three-quarters of the RPV wall thickness (3/4T) location.

Confirm that the limiting beltline material for the cooldown curves, which has an ART of 175 OF at 1/4T, is Plate C-506-1, and the materials information that DNC used in the ART calculation is from the LRA for MPS2.

(b)

The submittal stated that "[t]he development of the beltline P-T limits was established using ASME [American Society of Mechanical Engineers Boiler and Pressure Vessel Code] Section Xl, Appendix G, 2002 Addenda."

Confirm that DNC used the Appendix G (2002 Addenda) formulas based on the heatup or cooldown rate to calculate the applied stress intensity factor due to the thermal gradient. If an alternative approach of using a thermal stress distribution resulting from a thermal modeling (closed-form, finite element, or finite difference) method was used to calculate the applied thermal stress intensity factor, please provide an appropriate description and discussion of the thermal modeling method.

Also, address the sensitivity of the assumed heat transfer coefficient for convection (h) between the coolant and the vessel on the licensee's P-T limits if the licensee's heat transfer coefficient is different from 1000 btu/hr-ft.ft-0F commonly used in P-T limit applications.

(c)

Provide step-by-step calculations leading to the "indicated cold leg temperatures" at approximately 500 psia and 2000 psia of the heatup and cooldown limits for the limiting beltline material. The response for these four examples (i.e. at 500 and 2000 psia for the heat-up curve and at 500 and 2000 psia for the cooldown curve) should include (1) the pressure and temperature adjustments that were considered to account for instrument errors and conditions caused by different numbers of reactor coolant pumps in operation, and (2) the temperature differences between the reactor vessel coolant and the vessel beltline metal at 1/4T for the cooldown limits and the temperature differences between the reactor vessel coolant and the vessel beltline metal at 3/4T for the heat-up limits.

Serial No. 307A Docket No.

50-336 Supplement: RCS Heatup/Cooldown Limits Page 3 of 14 DNC Resnonse

2.

(a)

The limiting beltline material for the heatup curve is plate C-506-1 with a 3A T ART = 144.1 OF. The limiting beltline material for the cooldown curve is plate C-506-1 with a 1/4 T ART = 175.20F. The initial RTNDT and chemistry factor used in the ART calculation is from MPS2 LRA Table 4.2.2. The 54 EFPY fluence used to calculate the delta RTNDT is taken from WCAP-16012, Rev. 0, not the fluence listed in the LRA. The calculation of ART is documented in calculation 95-SDS-1 008MG, Rev. 05.

(b)

The applied stress intensity factor due to the thermal gradient is calculated using the heatup and cooldown rate formulas listed in section G2214.3 of ASME Section Xl, Appendix G, 2002 Addenda. No alternative approach for calculating thermal stress distribution is used. A heat transfer coefficient of 1,000 btu/hr-ft2-OF is used between the coolant and the vessel for the heat transfer analysis as this value is commonly used in P-T limit calculations.

(c)

See the following calculation for an example development of adjusted P-T limits.

Serial No. 307A Docket No. 50-336 Supplement: RCS Heatup/Cooldown-imits Enclosure I Page 4 Design Inputs Vessel Beitline Material: SA-533 Gr B, Class I Vessel Clad Thickness: 5/16" Vessel Clad Material : 304 SS t := 8.625in Ri:= 86.312in ART 25 := 175.2 ART75:= 144.1 RTndt:= 30 Min. Vessel wall thickness (in)

Vessel Inside Radius: excluding cladding (in)

Adjusted t/4 RTndt (IF) at the end of 54 EFPY Adjusted 3t/4 RTndt (IF) at the end of 54 EFPY Limiting head flange and vessel flange region RTndt (IF) for minimum bolt-up requirements Reactor vessel design pressure - 2500 psia Nominal Operating Pressure

- 2250 psia Indicated Temperature Uncertainties The bounding temperature uncertainty for temperature loops T-l 15, T-125, and T-351Y was found to be 13WF.

Temperature Uncertainty: 13 IF Indicated Pressure Correction Factors (IPCF)

The bounding pressure uncertainty for pressurizer pressure indicator loops P-1 03, P-1 03-1 and P-102A,B,C,D was found to be 51.2 psi. A value of 51.2 psi is used as input to generate the following Indicated Pressure Correction Factors.

For zero RCP's, For two RCP's, For three RCP's, IPCFORCP = 80.2 IPCF2RCP = 109.2 IPCF3RCP = 121.3 (psi)

(psi)

(psi)

Serial No. 307A Docket No. 50-336 Supplement: RCS Heatup/Cooldown Limits Enclosure I Page 5 To maximize the RCS operating window and minimize the negative potential impact on the LTOP setpoint, reactor coolant pump operation must be restricted at low RCS temperatures. The following tables show the assumed number of operating RCP's for the listed temperature ranges.

The "indicated" temperature was established by adding the 130F instrument uncertainty to the actual temperature.

RCP Operation for Heatup No. of RCP's Operating Cold Leg Temperature Range of Operation, T,, OF Indicated/(Actual) 2 70/(57) < Te

• 200/(187) 3 200/(187) < T,

• 500/(487) 4*

Tc > 500/(487)

• This value is presented for completeness but does not impact this analysis.

RCP Operation for Cooldown No. of RCP's Operating Cold Leg Temperature Range of Operation, T,, IF, Indicated/(Actual) 0 Tc < 1500F/(1370F) 2 150/(137) 5 T5

<2000F/(187) 3 200'F/(1 87) < T,

• 5000F/(487) 4*

Tc > 500/(487)

• This value is presented for completeness but does not impact this analysis.

Serial No. 307A Docket No. 50-336 Supplement: RCS Heatup/Cooldown Limits Enclosure I Page 6 Method of Analysis Reactor Vessel Beitline Pressure-Temperature Limits In developing the reactor vessel beltline pressure-temperature limits, the methodology outlined in the 2002 Addenda to ASME Section XI Appendix G is followed. The results for axial flaws are bounding so a circumferential flaw is not explicitly evaluated. In order to develop pressure-temperature limits, a transient heat transfer analysis was performed using the ANSYS general purpose finite element analysis code. The model uses two dimensional axi-symmetric elements (PLANE 55). There are 16 elements representing the thickness of the vessel wall and two representing the stainless steel cladding. Temperature dependent material properties are used in a transient analysis of the proposed heatup and cooldown time histories.

Note that the cladding is modeled in the thermal analysis but no credit is taken for the cladding in the stress analysis. The heat transfer coefficient which was used between the fluid and the cladding was taken as 1,000 Btu/hr-fl2-F and the OD was conservatively assumed to be insulated with a film coefficient of zero.

The allowable reference stress intensity factor (ksiIin), KIC, and the thermal stress intensity factor (ksi 4in), KIT, are calculated in accordance with the 2002 ASME B&PV Code,Section XI, Appendix G as required by IOCFR50 Appendix G. Paragraph G-2110 provides a relationship for KIc which is a function of the adjusted reference temperature (ART) at the postulated crack tip locations and the actual crack tip temperature.

KIc = 33.2 + 20.734eO.O2(T-AR) ksi '4in In the calculation of KIc, a one-quarter thickness ID and OD flaw is postulated in accordance with paragraph G-2120 of Appendix G. The stress intensity factor due to the radial thermal gradient, KIT, is computed using the heatup rate (HU) or cooldown rate (CR) in F/hr as described in G-2214.3.

KIT = 0.953 x 10-3 x CR x t2_5 ksi JAn KIT = 0.753 x 10-3 x HU x t2.5 ksi 4in For normal plant heatup and cooldown the allowable pressure is developed to satisfy paragraph G-2215 based on the following relations using Mm defined in G-2214.1.

KIM = (KIC - KIT)/2 ksi'lin and P = (KIC - KIT)/2Mm X (t/Ri) psi As required by G-2215, for heatup the 3/4t flaw is evaluated and for cooldown the 1/4t flaw is evaluated. The results of the heatup case are compared to the isothermal 1/4t pressure (KIT

= 0) to produce a bounding composite beltline curve. Althought not required by Appendix G, the cooldown case is also compared to the isothermal case.

Serial No. 307A Docket No. 50-336 Supplement: RCS Heatup/Cooldown Limits Page 7 Calculations for Heatup at 60°F/hr to 1870F. then 800F/hr to 2620F? then 1000F/hr to 5500F:

(temperatures and pressures are unadlusted)

Reactor vessel coolant inlet temperature, Tfluid, 1/4t (T2 5) and 3/4t (T75) temperatures from Ansys analysis.

ksi:= lOOOpsi j:= I.. 2 hr

°F OF time.:=

Tfluidhu :=

T2 5j:=

T75i =

F6_1 F93.0-771 64 Governing Eguations Reference Critical Stress Intensity Factor for 3/4t flaw (Article G-2 110) 0.02. (T75,-ART75~

KlCoutsideflaw.= 33.2ksiiFin + 20.734ksi in~e J

J Membrane stress for 3/4t flaw (Article G-2214.1)

MmOutsideFlaw:

0.8934it MmOutsideflaw =2.6234Th-Thermal Stress Intensity Factor for 60°F/hr, 80°F/hr and 100°F/hr heatup rates considering a 3/4t flaw (Article G-2214.3).

Ri = 86.312in t = 8.625 in 60°F/hr:

K1T60outsideflaw:= 0.753

• 60-t2 5

. 2 in 80°F/hr:

KIT80outsideflaw:= 0.753 2-1.

80.t25

.2 KlT60outsideflaw = 9.871 ksi4hn KlT80outsideflaw = 13.161 ksi..j-1000F/hr:

KlT100outsideflawO 0.753

.j-~ 1.

j10t 2.5 KT1TI0outsideflaw = 16.45 1 ksi4ThFi in2

Serial No. 307A Docket No. 50-336 Supplement: RCS Heatup/Cooldown Limits Page 8 Allowable Pressure for heatup rates of 60IF/hr, 80°F/hr and 100°F/hr (Article G-2215(a)(4)(b)).

KICoutsideflawi - KIT60outsideflaw PHU60 :=

2-MmOutsideFlaw KlCoutsideflawj - KmOoutsideflaw PHU80.:=

J 2 MmoutsideFlaw KlCoutsideflaw. - KITlOOoutsideflaw (t PHUIOO :=

2 i

J 2'MmOutsidefaw R)

Heatup: Summary of Results for a 3/4t (outside surface) Flaw (temperatures and pressures are unadjusted) hr time. =

J Tfluidhu. =

KlCoutsideflaw. =

PHU60. =

30 l 37.671 ksi.4n 53 psi 1 271.61 1116.281 F12027 PHU80. =

PHUIOO. =

@f psi 3

psi

Serial No. 307A Docket No. 50-336 Supplement: RCS Heatup/Cooldown Limits Page 9 Calculations for Cooldown at 1000F/hr to 2071F then 500F/hr to 571F: (temperatures and pressures are unadjusted)

Reactor vessel coolant inlet temperature, Tfluid, 1/4t (T25) and 3/4t (T7s) temperatures from Ansys analysis.

hr time. :=

J j := 1..2 OF 0F Tfluidc. j TC25 :

F43 F89.4 T75. =

Grnvemnin~ Eanations (from Reference 4. Annendix Gr)

Reference Critical Stress Intensity Factor for 1/4t flaw (Article G-21 10).

KICinsideflaw.= 33.2ksij..ni + 20.734ksi*.Thie0.02-(Tc 25j-ART25)

Membrane stress for 1/4t flaw (Reference 4 Article G-2214.1).

MmlnsideFlaw:

0.926Nrt Mmjnsideclaw = 2.72Nji~n Thermal Stress Intensity Factor for 50'F/hr and 100°FIhr cooldown rates considering a 1/4t flaw (Article G-2214.3).

Ri = 86.312in t = 8.625in 50'F/hr:

KITsoinsideflaw := 0.953

- 10 50 t25 in 100 F/hr:

KlTMO0insideflaw:= 0.953

-.10 3.00.t2 in KlT5Oinsideflaw = 0.41 0ksi -NITi KITI O0insideflaw = 20.82 Wksk/in

Seral No. 307A Docket No. 50-336 Supplement: RCS Heatup/Cooldown LimIts Page 10 Allowable Pressure for cooldown rates of 500F/hr and 100IF/hr (Article G-221 5(a)(4)(b)).

KJcinsideflaw - KIT5Oinsideflaw t

PCD50 :=

2 i.1 J

2'MmlnsideFlawR)

KICinsideflaw. - KIT100insideflaw PCDIOO 2 Mmlnsideplaw CRiJ Cooldown at 100IF/hr and 50IF/hr: Summary of Results for a 1/4t Flaw (temperatures and pressures are unadlusted)

OF Tfluidcdj =

KlCinsideflaw. =

PCD5O =

PCDIOO. =

E4l 236.7 ksn i)n4 psi 3967 psi l

1 E41.4 5

378

Serial No. 307A Docket No. 50-336 Supplement: RCS Heatup/Cooldown Limits Page I1 rate S 5°F/hr) j:= L. 2 k:= 1..2 Calculations for Isothermal Conditions (temperature i Governing Equations for a 1/4t Flaw (Appendix G. Article G-221 5(a)(4)(a))

°IF OF Two temperature ranges are defined, one for comparision with the heatup TtluidO :=

Tflu'dl *=

curves, and one for the cooldown. The allowable stress intensity factor for T jdU kT '

both the inside and outside flaws is calculated:

93 R43 271.6 ION Reference Critical Stress Intensity Factor for 1/4t flaws (Article G-2110O)

KIC25 0.:= 33.2ksi-4Th + 20.734ksi-4n e T

i J)

KYC251 := 33.2ksi-r4n + 20.734ksikhne T

k

)

k Membrane stress for 1/4t flaw (Article G-22 14. 1)

Mm25= 0.9264it Mm25 = 2.72N11nh Reference Critical Stress Intensity Factor for 3/4t flaws (Article G-2 1 10) 0 (Tnuldo -ART7S)

KIC75 0 := 33.2ksi.4hn + 20.734ksinte J

KIC75I := 33.2ksi.4Tn + 20.734ksi-ine T

k

)

k Membrane stress for 314t flaw (Article G-2214.l1)

Mm75 := 0.8934ir Mm7s = 2.6234hn Allowable Pressure considering 1/4t flaw (Article G-221 5(a)(4)(a))

R; = 86.312in t = 8.625in KIC25 0 t

PIS00250 :=-

2Mm2~5 Ri KIC25Ik t PjS0 02 5 1 :=

k 2Mm25 Ri Allowable Pressure considering 1/4t flaw (Article G-2215(a)(4)(a))

R; = 86.312in t = 8.625in KIC750.

t PIS0075o =

J 2Mm7 5 Ri KlC751k t

PIS007I :=

Serial No. 307A Docket No. 50-336 Supplement: RCS Heatup/Cooldown Limits Enclosure I Page 12 Isothermal Conditions (temverature rate S 5°F/hr): Summary of Results for a 1/4t Flaw (temperatures and pressures are unadiusted)

TfludO =

KlC250 PIS00250. =

37.21

ksi4, L83 psi 71.6 175.76 2

Tfluidlk KIC251

=

PIS00251k =

0 l 113.661 Iksi-4Fn 2

psi 1°.

38.293 7041 Isothermal Conditions (temperature rate

• SF/hr): Summary of Results for a 3/4t Flaw (temperatures and pressures are unadiusted)

TfluidO =

KIC750 =

PIS00750. =

93.01 40.66 ksi.4in psi 271.61 1298.741 W61 Tfluidlk KlC751

=

PIS00751

=

l.

i83.071 ksi.-in psi l

~

150l 42.6861813

Serial No. 307A Docket No. 50-336 Supplement: RCS Heatup/Cooldown Limits Page 13 Normal Heatup : Adjusted Values for Tech Spec Figure Phu is taken as the lesser of pressure from the heatup and isothermal calculations. As can be seen from examination of the isothermal results on the previous pages, the isothermal results do not govern at any point during the heatup.

OF psig psig psig j := 1.2 Tfluidhu Phu60.

Phu80.

Phu100:

L93.0I 50I E

Values of temperature will be adjusted by 130 F to account for temperature instrument uncertainty.

Thu.

Tfluidhu. + 13 Calculated values of pressure will be adjusted for indicated pressure correction factors (IPCF) and corrected by 14.7 psi to absolute pressure. For temperatures of 200TF and below, only two pumps may run, so IPCF2RCP is applied (109.2 psi). For temperatures above 200TF and below 5000F, IPCF3RCP is applied (121.3psi).

k:= 1..1 I1:= 2..2 Phu60k Phu6Ok - 109.2 + 14.7 Phu6O:

Phu6O, - 121.3 + 14.7 PhU8ok PhuSk - 109.2 + 14.7 Phu8O:

Phu80 - 121.3 + 14.7 PhuI00k := Phulo0o - 109.2 + 14.7 PhulOI0 := PhuI00, - 121.3 + 14.7 Thus, for heatup at 600F/hr to 200'F (indicated RCS temperature), then 80IF/hr to 2751F. then I 000F/hr to 5500F: (temperatures and pressures below are adjusted for use in the Technical Specification figure development)

OF Thu =

Phu60. =

Phu80.

PhuI0J PhuComposite=

J 3

J 1

106.0 436 3

31 3

Therefore, the maximum allowable pressure at 106'F is 436 psi (limited to the 60'F/hr heatup rate).

The maximum allowable pressure at 284.61F is 1795psi (limited to the 1 000F/hr heatup rate).

Serial No. 307A Docket No. 50-336 Supplement: RCS Heatup/Cooldown Limits Enclosure I Page 14 Normal Cooldown : Adlusted Values for Plotting Ph. is taken as the lesser of pressure from the heatup and isothermal calculations. The isothermal values govern down to about 1650F for the 50'F/hr table and 185TF for the 1 000F/hr table. This table provides unadjusted beltline P/T limits for use in the LTOP evaluation, reference 21.

psi psi j :=1..2 TfluidcdJ

=

Ped50. :=

Ped10O. '

J J

Values of temperature will be adjusted by 13° F to account for instrument uncertainty.

Ted.:= Tfluidcd. + 13 J

3 Calculated values of pressure will be corrected for the indicated pressure correction factors (80.2 psi for zero pump operation below 1500F, 109.2 psi for two pump operation for 150 0F5 TC <2000F, 121.3 psi for three pump operation above 200'F), and 14.7 psi to correct to absolute pressure.

i:= L..I k:= 2..2 Pcd50; := Pcd5Oi - 121.3 + 14.7 PcdIO0 := PCdlooi-121.3 + 14.7 PCdSOk := Pcd5Ok-80.2 + 14.7 PedI00k := PcdI0k - 80.2 + 14.7 Thus, for cooldown at 100 0F/hr to 2200F then 50°F/hr to 70TF (temperatures and pressures are adiusted for use in the Technical Specification figure development).

OF Tcd.

psi Pcd5O =

504 psi PedI00. =

33 psi PcdComposite.i:

F 3

1504 Therefore, the maximum allowable pressure at 256 0F is 1981 psi (limited to the I 000F/hr cooldown rate). The maximum allowable pressure at 11 8 0F is 504psi (limited to the 50'F/hr cooldown rate).

Serial No. 307A Docket No.

50-336 ENCLOSURE 2 REPLACEMENT ATTACHMENTS 1 - 4 OF DNC LETTER DATED JULY 14 2005 DOMINION NUCLEAR CONNECTICUT. INC.

MILLSTONE POWER STATION UNIT 2

Serial No. 307 Docket No.

50-336 ATTACHMENT 1 PROPOSED REVISION TO TECHNICAL SPECIFICATIONS (LBDCR 05-MP2-003)

REACTOR COOLANT SYSTEM HEATUP/COOLDOWN LIMITS EVALUATION OF PROPOSED LICENSE AMENDMENT DOMINION NUCLEAR CONNECTICUT. INC.

MILLSTONE POWER STATION UNIT 2

Serial No. 307 Docket No.

50-336 Heatup/Cooldown Limits Page 1 of 13 Evaluation of Proposed License Amendment

3.0 BACKGROUND

3.1 Results of The Most Recent Capsule Removal And Evaluation 3.2 Reason for Proposed Amendment

4.0 TECHNICAL ANALYSIS

4.1 Details of the Proposed Amendment 4.2 Safety Summary

5.0 REGULATORY ANALYSIS

5.1 No Significant Hazards Consideration 5.2 Applicable Regulatory Requirements/Criteria

6.0 ENVIRONMENTAL CONSIDERATION

Serial No. 307 Docket No.

50-336 Heatup/Cooldown Limits Page 2 of 13

1.0 DESCRIPTION

Pursuant to 10 CFR 50.90, Dominion Nuclear Connecticut, Inc. (DNC) hereby requests to amend Operating License DPR-65 for Millstone Power Station Unit 2 (MPS2). The enclosed license amendment request proposes to revise Technical Specification 3.4.9.1, "Reactor Coolant System." The proposed changes will modify the reactor coolant system (RCS) heatup and cooldown limits.

The associated technical specification bases will be updated to address the proposed changes.

2.0 PROPOSED CHANGE

2.1 The proposed amendment will modify Technical Specification (TS) Table 3.4-2 as follows:

1. Replace the heading "Heatup" with "Heatup*" and add the following note to the bottom of the table:

" These limitations also apply to hydrostatic and leak test conditions."

2.2 Cooldown Column:

1. Delete the following cooldown limits:

a. Limit related to RCS not vented (Indicated Cold Leg Temperature 5 1000F)

b. Limit related to RCS not vented (100OF < Indicated Cold Leg Temperature

• 2300F)

c. Limit related to RCS vent 2 2.2 square inches (Indicated Cold Leg Temperature < 1900F)

2. Limit related to Indicated Cold Leg Temperature

• 2300F is changed to Indicated Cold Leg Temperature

• 2200F. The wording "during unanticipated temperature excursions" is deleted.

3.

Limit related to Indicated Cold Leg Temperature > 2300F is changed to Indicated Cold Leg Temperature > 2200F.

The limit is changed from

• 800F/hour to

• 1000F/hour.

2.3 Heatup Column:

1. Limit related to Indicated Cold Leg Temperature

• 2200F is changed to Indicated Cold Leg Temperature

• 2000F.

The limit is changed from

• 300F/hour to

• 600F/hour.

Serial No. 307 Docket No.

50-336 Heatup/Cooldown Limits Page 3 of 13

2. Limit related to 2200F < Indicated Cold Leg Temperature

• 2750F is changed to 200OF < Indicated Cold Leg Temperature 5 2750F.

The limit is changed to 80OF/hour.

3. Delete "Inservice Hydrostatic and Leak Testing", Delete "indicated Cold Leg Temperature," and Delete "Limit: < 5 OF/hour for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> prior to and during inservice hydrostatic and leak testing operations above the heatup limit curve."

The old and new limits are summarized in the table below. The use of the proposed RCS pressure/temperature (P-T) limits and associated heatup/cooldown rates is covered in more detail in the addition to the bases of Technical Specification 3.4.9.1.

Serial No. 307 Docket No.

50-336 Heatup/Cooldown Limits Page 4 of.13 CURRENT PROPOSED Heatup Heatup*

Indicated Cold Leg Limit Indicated Cold Leg Limit Temperature Temperature

< 220 0 F

< 30 OF / hour

< 200OF

.< 60 F / hour 220OF<T<275OF

<50OF/hour 200OF<T<2750F

<80OF/hour

> 275 0F 100 OF/ hour

> 275 OF

< 100 'F / hour Cooldown Cooldown RCS Temperature Limit Indicated Cold Leg Limit (Tavg)

Temperature

< 100 OF

< 5 OF/ hour

<220 OF 50 'F / hour If RCS not vented 1000F<T<230'F s30OF/hour

>220OF

< 100OF/hour If RCS not vented

< 190OF

< 50 OF / hour If RCS vent z 2.2 square inches s230 OF

< 50OF/hour During unanticipated temperature excursions

> 230 F

< 80 F /hour Hydrostatic Testing

• These limitations also apply to hydrostatic and leak test conditions Limit

<5 jF / hour For 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> prior to and during inservice hydrostatic and leak testing operations above the heatup limit curve.

Serial No. 307 Docket No.

50-336 Heatup/Cooldown Limits Page 5 of 13 Brief explanation of the changes:

1. Replacement of the separate hydrostatic and leak test limit with the requirement that these conditions do not exceed the heatup limits adds additional administrative margin by requiring that these tests be performed at a higher temperature where there is greater available fracture toughness of the RCS materials. The requirement to remain isothermal (rate < 50F / hour) for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> prior to and during hydrostatic and leak testing when operating above the heatup curve is no longer needed as operation above the heatup curve is no longer allowed.

2. As a result of the revised fracture mechanics evaluation there is no longer a need for an alternate cooldown limit to accommodate unanticipated temperature excursions. Previously, a very restrictive rate or RCS venting requirements were necessary to provide adequate low temperature overpressure protection (LTOP) controls.

Currently the proposed rate of 500F/hour is anticipated to provide adequate flexibility to accommodate unanticipated temperature excursions within the LTOP regime. In addition, the revised fracture mechanics evaluation provides adequate operating margin negating the necessity to establish RCS vented conditions in conjunction with the normal cooldown curve.

These proposed modifications provide adequate operational flexibility concurrent with LTOP protection.

Detailed explanation is provided in section 4.1.

2.4.

The proposed amendment will modify TS Figure 3.4-2a and Figure 3.4-2b as follows:

1. Figure 3.4-2a will be replaced with a new curve valid up to 54 EFPY.

Figure 3.4-2a addresses plant heatup and is currently valid up to 20 EFPY. The heatup rate limits contained in Table 3.4-2, have been changed in conjunction with the new curve.

2. Figure 3.4-2b will be replaced with a new curve valid up to 54 EFPY. Figure 3.4-2b addresses plant cooldown and is currently valid up to 20 EFPY.

The cooldown rate limits contained in Table 3.4-2, have been changed in conjunction with the new curve. The two cooldown curves available when RCS temperature is below 230 OF are replaced by a single curve.

Brief explanation of the changes:

The proposed P-T curves permit a higher RCS pressure for a given RCS temperature, and the proposed heatup and cooldown temperature change rates allow a higher rate than currently allowed. The new curves and associated rates

Serial No. 307 Docket No.

50-336 Heatup/Cooldown Limits Page 6 of 13 have been calculated using standard approved methods that ensure the margins of safety required by 10CFR50, Appendix G are maintained. Therefore, the proposed changes will have no adverse effect on plant safety.

The impact of the revised curves and rates on the LTOP controls has been evaluated. It has been determined the current LTOP administrative limits set in the technical specifications provide adequate protection to the required LTOP safety requirements. Therefore, the proposed changes will have no adverse effect on plant safety.

Detailed explanation is provided in section 4.1.

2.5 The bases of the affected technical specifications will be revised to discuss these changes. The following changes are incorporated:

1. Page B 3/4 4-6b Delete Item 9 discussing P-T limit applicable to unanticipated operation. This is no longer relevant as the cooldown curve specific to unanticipated operation has been removed from figure 3.4-2b.

In the final sentence delete "and for inservice and hydrostatic testing," which occurs twice and add the following sentence. "For inservice leak and hydrostatic testing, use of the heatup curve on Figure 3.4-2a and associated rates provide a conservative limit in lieu of a curve developed specifically for inservice leak and hydrostatic testing.

Therefore a separate leak and hydrostatic curve is not explicitly included on Figure 3.4-2a."

2. Page B 3/4 4-7 Replace 161 OF with 1630F. Replace 10.50F with 130F. Replace 40.50F with 430F.

Serial No. 307 Docket No.

50-336 Heatup/Cooldown Limits Page 7 of 13

3. Page B 3/4 4-7a Add Insert D. Replace RTNDT with Adjusted Reference Temperature (ART).

Replace 900F with 500F. Replace Branch Technical Position RSB 5-2 with ASME Section Xl, Appendix G. Replace 20 EFPY with 54 EFPY.

Replace RTNDT with ART. Replace 1450F with 1750F. Replace 2630F with 2730F.

3.0 BACKGROUND

3.1 Results of The Most Recent Capsule Removal And Evaluation During refueling outage 14, reactor vessel material surveillance capsule W-83 was removed from the reactor vessel for subsequent evaluation and analysis.

The capsule specimens were destructively tested and a fluence analysis was performed which considered the actual core history and core loading patterns. The results of this analysis was documented in WCAP-1 6012, Rev. 0, "Analysis of Capsule W-83 from the Dominion Nuclear Connecticut Millstone Unit 2 Reactor Vessel Surveillance Program," February 2003. WCAP-16012, Rev. 0 was submitted to the Nuclear Regulatory Commission (NRC) by a letter titled "Millstone Nuclear Power Station, Unit No. 2 Submittal of Third Reactor Vessel Surveillance Capsule Report" dated February 26, 2003. This report provided relevant information for use in revising the P-T limits.

The results of the most recent capsule removal and evaluation (capsule W-83) provide the most accurate results available and consider the complete power history and core loading patterns to provide revised projections of accumulated vessel fluence and material degradation.

3.2 Reason for Proposed Amendment To update Millstone Unit 2 TS 3.4.9.1, "Reactor Coolant System," to incorporate the results of a new analysis that has been performed to develop new RCS P-T curves and associated heatup and cooldown rate limits.

4.0 TECHNICAL ANALYSIS

4.1 Details of the Proposed Amendment The enclosed license amendment request proposes to revise Technical Specification 3.4.9.1, "Reactor Coolant System." The proposed changes will modify the RCS P-T curves and the associated heatup and cooldown rate limits.

The associated technical specification bases will be updated to address the proposed changes.

Serial No. 307 Docket No. 50-336 Heatup/Cooldown Umits Page 8 of 13 The projected fluence for 54 EFPY was chosen as the basis for the proposed heatup and cooldown limitations. The limiting reactor vessel material was chosen from all reactor vessel materials expected to receive neutron fluence equal to or greater than 1 x 1017 n/cm2.

As described in position 1.1 of Regulatory Guide 1.99, Rev. 2, chemistry factor (CF) and ART were calculated using Table 1, Table 2 and Equation

2. This provided a more conservative CF and ART than position 2.1 of the regulatory guide (due to the reduced margin term provided by position 2.1).

As described in position 2.2 of Regulatory Guide 1.99, Rev. 2, all available surveillance data was used to predict the limiting material upper shelf energy degradation as this provided more conservative shift than position 1.2 of the regulatory guide.

All materials have been projected to exceed the 50 ft-lb requirement at 54 EFPY.

The development of the beltline P-T limits was established using ASME Section Xl, Appendix G, 2002 Addenda. This edition of the Code, approved for use in the 2004 edition of 10 CFR 50, provides a reference fracture toughness curve (Kic) for establishment of the beltline P-T limits. The additional requirements of 10 CFR 50 Appendix G were also considered in the establishment of the P-T limits.

A revision to the P-T limits has the potential to impact the existing LTOP evaluation and administrative limits. However, a revision to the existing LTOP evaluation has determined the existing LTOP administrative limits described in the technical specifications are still acceptable to protect the new proposed P-T limits and associated rates.

ASME Section Xl, Appendix G requirements have changed.

Earlier versions of ASME Section Xl, Appendix G did not provide guidance for determination of the LTOP enable temperature.

Therefore, Branch Technical Position RSB 5-2 of NUREG-0800 was used for guidance in earlier LTOP calculations. The currently approved version of ASME Section Xl, Appendix G now provides methodology and requirements for calculation of the LTOP enable temperature.

Therefore, the supporting analysis for this submittal was performed in accordance with the currently approved version of ASME Section Xl, Appendix G, and reference to Branch Technical Position RSB 5-2 is no longer required.

A new analysis has been performed to develop new RCS P-T curves and associated heatup and cooldown rates. The heatup and cooldown rates will be increased to provide flexibility during plant heatup and cooldown, and especially during equipment manipulations such as securing reactor coolant pumps (RCPs), swapping shutdown cooling (SDC) heat exchangers, and initiating SDC.

This need was identified during the review of the 1995 and 1996 heatup/cooldown events that resulted in violation of the technical specification requirements.

These were

Serial No. 307 Docket No.

50-336 Heatup/Cooldown Limits Page 9 of 13 documented in Millstone Unit 2, Licensee Event Report (LER) 95-030-00, "Violation of Technical Specification 3.0.4 During Reactor Plant Heatup," dated August 22, 1995, and LER 96-001-00, "Reactor Coolant System Heatup Rate Exceeded Technical Specification Limit," dated January 30, 1996. The new analysis also incorporates updated instrument uncertainties.

Figure 3.4-2a addresses plant heatup and is currently valid up to 20 EFPY. Figure 3.4-2a will be replaced with a new curve valid up to 54 EFPY. The associated heatup rate limits contained in Table 3.4-2 have been changed as a result of the new analysis.

The new rate limits have been simplified and updated for greater consistency between heatup and cooldown. The hydrostatic and leak test limit are now administratively controlled by the heatup limit and not explicitly shown on the figure.

Figure 3.4-2b addresses plant cooldown and is currently valid up to 20 EFPY.

Figure 3.4-2b will be replaced with a new curve valid up to 54 EFPY.

The associated cooldown rate limits contained in Table 3.4-2 have been changed as a result of the new analysis.

Previously, a very restrictive rate or RCS venting requirements were necessary to provide adequate LTOP controls.

Currently the proposed rate of 500F/hour is anticipated to provide adequate flexibility to accommodate unanticipated temperature excursions within the LTOP regime.

In addition, the revised fracture mechanics evaluation provides adequate operating margin negating the necessity to establish RCS vented conditions in conjunction with the normal cooldown curve.

These proposed modifications provide adequate operational flexibility concurrent with LTOP protection.

The distinction between operation with the RCS vented and not vented and the multiple cooldown rates available below 2300F are no longer required and have been removed.

4.2 Safety Summary The proposed changes will modify the RCS P-T limits and associated heatup and cooldown rates. The majority of the proposed changes are being made as a result of the new P-T and LTOP analyses performed. The new P-T curves and associated heatup and cooldown rates were developed in accordance with the requirements and methods described in 10CFR50, Appendix G and are consistent with the criteria contained in the Standard Review Plan Section 5.3.2. The specific details of each proposed change have already been presented. This safety assessment will evaluate the safety significance of the above changes.

Serial No. 307 Docket No.

50-336 Heatup/Cooldown Limits Page 10 of 13 RCS Heatup and Cooldown Changes

1. A new analysis has been performed to develop new RCS P-T curves and associated heatup and cooldown rate limits. The heatup and cooldown rates will be increased to provide flexibility during plant heatup and cooldown, and especially during equipment manipulations such as securing RCPs, swapping SDC heat exchangers, and initiating SDC. The new curves have been calculated using standard approved methods that ensure the margins of safety required by 10CFR50, Appendix G are maintained. Therefore, the proposed changes will have no adverse effect on plant safety.

The new analysis includes updates to the design inputs not reflected in the current analysis. These updates include the following items.

a. Revised instrument uncertainties have been incorporated in the development of the MPS2 heatup and cooldown curves. The revised uncertainties reflect a decrease in the uncertainty associated with monitoring RCS pressure and an increase in the uncertainty associated with monitoring RCS temperature. This proposed change will have no adverse effect on plant safety.

b. The population of reactor vessel materials included in the selection of the most limiting reactor vessel material has been increased to include all materials projected to receive a neutron fluence of at least 1 x 1017 n/cm2 at 54 EFPY.

The limiting materials remain unchanged from the prior P-T calculations.

This proposed change will have no adverse effect on plant safety.

2. Figure 3.4-2a has been modified to remove the hydrostatic and leak test limit line. The hydrostatic and leak test limit will now be administratively controlled by the heatup limit. Administratively limiting hydrostatic and leak test to the heatup limit provides additional margin to the Appendix G requirements. Table 3.4-2 has been modified to remove the Inservice Hydrostatic and Leak Testing item and to add a note indicating heatup limitations also apply to hydrostatic and leak test conditions. The requirement to remain isothermal (rate < 50F / hour) for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> prior and during hydrostatic and leak test above the heatup curve is no longer needed as operation above the heatup curve is no longer allowed.

These proposed changes will have no adverse effect on plant safety.

3. In some cases the proposed heatup and cooldown temperature change rates allow a higher rate than currently allowed.

However, the new curves and associated rates have been calculated using standard approved methods that ensure the margins of safety required by 10CFR50, Appendix G are maintained.

Therefore, the proposed changes will have no adverse effect on plant safety.

Serial No. 307 Docket No.

50-336 Heatup/Cooldown Limits Page 11 of 13

5.0 REGULATORY ANALYSIS

5.1 No Significant Hazards Consideration In accordance with 10CFR50.92, DNC has reviewed the proposed changes and has concluded that they do not involve a significant hazards consideration (SHC). The basis for this conclusion is that the three criteria of 10CFR50.92(c) are not compromised as evaluated below:

1. Does the proposed amendment involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No.

The proposed changes are a result of the new analysis of the RCS P-T limits and associated heatup/cooldown rates. These changes will support plant operation to 54 EFPY and provide flexibility during plant heatup and cooldown, especially during equipment manipulations such as securing RCPs, swapping SDC heat exchangers, and initiating SDC.

The hydrostatic and leak test limit will now be administratively controlled by the heatup limit. Administratively limiting hydrostatic and leak test to the heatup limit provides additional margin to the Appendix G requirements.

Table 3.4-2 has been modified to remove the Inservice Hydrostatic and Leak Testing item and to add a note indicating heatup limitations also apply to hydrostatic and leak test conditions.

The requirement to remain isothermal (rate < 50F / hour) for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> prior and during hydrostatic and leak test above the heatup curve is no longer needed as operation above the heatup curve is no longer allowed.

The proposed changes to the RCS P-T limits and rates of temperature change are based on the new analysis. This analysis uses standard approved methods that ensure the margins of safety required by 1 OCFR50, Appendix G are maintained. The other changes discussed are more restrictive enhancements to technical specification requirements. Therefore, the proposed changes will not result in a significant increase in the probability or consequences of an accident previously evaluated.

Serial No. 307 Docket No.

50-336 Heatup/Cooldown Umits Page 12 of 13

2. Does the proposed amendment create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No.

The proposed changes will not alter the plant configuration (no new or different type of equipment will be installed) or require any new or unusual operator actions. They do not alter the way any structure, system, or component functions and do not alter the manner in which the plant is operated.

The proposed changes do not introduce any new failure modes.

Therefore, the proposed changes will not create the possibility of a new or different kind of accident from any accident previously evaluated.

3. Does the proposed amendment involve a significant reduction in a margin of safety?

Response: No.

The proposed changes will modify the RCS P-T limits, and the RCS heatup and cooldown limits. The proposed changes are being made as a result of the new P-T and LTOP analyses performed.

The new P-T curves and heatup and cooldown rates are developed in accordance with the requirements and methods described in 10CFR50, Appendix G and are consistent with the criteria contained in the Standard Review Plan Section 5.3.2. This will ensure the integrity of the reactor vessel is maintained during all aspects of plant operation. Therefore, there is no significant effect on the probability or consequences of any accident previously evaluated and no significant impact on offsite doses associated with previously evaluated accidents. This license amendment request does not result in a reduction of the margin of safety as defined in the bases for the technical specifications addressed by the proposed changes.

As described above, this license amendment request does not impact the probability of an accident previously evaluated, does not involve a significant increase in the consequences of an accident previously evaluated, does not create the possibility of a new or different kind of accident from any accident previously evaluated, and does not result in a significant reduction in a margin of safety.

Therefore, DNC has concluded that the proposed changes do not involve an SHC.

5.2 Applicable Regulatory Requirements/Criteria The U. S. Nuclear Regulatory Commission (NRC) has established requirements in Appendix G to 10 CFR Part 50 to protect the integrity of the reactor coolant pressure boundary in nuclear power plants. Appendix G to 10 CFR Part 50 also incorporates, by reference, the requirements found in Appendix G to Section Xl of the ASME

Serial No. 307 Docket No. 50-336 Heatup/Cooldown Limits Page 13 of 13 Boiler and Pressure Vessel Code as the basis for the establishment of facility P-T limit curves. Regulatory Guide 1.99, Rev. 2, "Radiation Embrittlement of Reactor Vessel Materials", contains methodologies for determining the increase in ductile-to-brittle transition temperature and the decrease in upper-shelf energy resulting from neutron radiation, which is used as input to the P-T Limit and LTOP calculations.

Standard Review Plan (SRP) Section 5.3.2, "Pressure-Temperature Limits and Pressurized Thermal Shock" provides additional guidance applicable to the development of P-T limits.

The development of the P-T and LTOP limits were established using ASME Section Xl Appendix G, 2002 Addenda. This edition of the Code, approved for use in the 2004 edition of 10 CFR 50, provides a reference fracture toughness curve (Kg:) for establishment of the beltline P-T limits. The additional requirements of 10 CFR 50 Appendix G were considered in the establishment of the P-T limits.

6.0 ENVIRONMENTAL CONSIDERATION

DNC has determined that the proposed amendment would change requirements with respect to use of a facility component located within the restricted area, as defined by 10 CFR 20, or it would change inspection or surveillance requirements.

DNC has evaluated the proposed change and has determined that the change does not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluent that may be released off site, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed amendment meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.

Serial No.05-307 Docket No. 50-336 ATTACHMENT 2 PROPOSED REVISION TO TECHNICAL SPECIFICATIONS (LBDCR 05-MP2-003)

REACTOR COOLANT SYSTEM HEATUP/COOLDOWN LIMITS TECHNICAL SPECIFICATIONS MARKED-UP PAGES DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2

4 y-L8478 TABLE 3.4-2 REACTOR COOLANT SYSTEM -

HEATUP AND COOLDOWN LIMITS Cooldown Heatup; Indicated Cold Leg Limit Indicated Cold Leg Limit Temperature Temperature

• < 1000F S

5°F/hour L))

if RCS not vented.

-*0F/hour 10F<T*T.230°F

< 30°F/hour j

F < T* 275°F if RCS not vented.

*4"F/hour

< 190°F

< 50°Flhour if RCS vent 2 2.2 J

> 275°F

< 100°F/hour square inches.-

during unanticipate temperaturs o

n li i c uFo u rr d tLeak Tsi A>Temeratue_/

our prior to and

, during inservice hydrostatic and leak testing operations above the heatup litnit curve.

A e~e fim;niz1,i;0is a04 apply TO HY%/ro sT^ ric n/eki s

)

MILLSTONE - UNIT 2 3/4 4-19 Amendmnent No.-H

-1

ec?*4c4 4 i'i

tscd F) t,2tkeactor Coolant System tations for Up to 20 EFPY Figure 3.4-2a MILLSIDNE - UNIT 2 3/4 4-19a Amendment No.

+

BASES SECTION PAGE 3/4.4 REACTOR COOLANT SYSTEM 3/4.4.1 COOLANT LOOPS AND COOLANT CIRCULATION........................ B 3/4 4-1 3/4.4.2 SAFETY VALVES........................................

B 3/4 4-ld 3/4.4.3 RELIEF VALVES........................................

B 3/4 4-2 3/4.4.4 PRESSURIZER.......................................

B 3/4 4-2a 3/4.4.5 STEAM GENERATORS.......................................

B 3/4 4-2a 3/4.4.6 REACTOR COOLANT SYSTEM LEAKAGE..................................... B 3/4 4-3 3/4.4.7 DELETED.......................................

B 3/4 4-4 3/4.4.8 SPECIFIC ACTIVITY.....................................

B 3/4 4-4 3/4.4.9 PRESSURE/TEMPERATURE LIMITS.....................................

B 3/4 4-5 3/4.4.10 DELETED.......................................

B 3/4 4-7c 3/4.4.11 DELETED.....................................

B 3/4 4-8 3/4.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) 3/4.5.1 SAFETY INJECTION TANKS.......

B 3/4 5-1 3/4.5.2 and 3/4.5.3 ECCS SUBSYSTEMS B 3/4 5-2 3/4.5.4 REFUELING WATER STORAGE TANK (RWST).......

B 3/4 5-2e 3/4.5.5 TRISODIUM PHOSPHATE (TSP).......

B 3/4 5-3 3/4.6 CONTAINMENT SYSTEMS 3/4.6.1 PRIMARY CONTAINMENT...................................

B 3/4 6-1 3/4,6.2 DEPRESSURIZATION AND COOLING SYSTEMS............................ B 3/4 6-3 3/4.6.3 CONTAINMENT ISOLATION VALVES..

................................... B 3/4 6-3b 314.6.4 COMBUSTIBLE GAS CONTROL...................................

B 3/4 6-4 3/4.6.5 SECONDARY CONTAINMENT..................................... B 3/4 6-5 MILLSTONE - UNIT 2 XII Amendment No. 66, 69, X, 404, i14, 48-, 24, -264, 26,

TABLE 3.4-2 REACTOR COOLANT SYSTEM HEATUPANDCOOLDOWN LMITS Cooldown Heatup*

Indicated Cold Leg Limit Indicated Cold Leg Limit Temperature Temperature S 2200F

• 50'F/hour

• 2000F

• 60'F/hour 2000<T*2750F 801F/hour

> 2200F

• 100'F/hour

> 2750F

• 100IF/hour I

I

• These limitations also apply to hydrostatic and leak test conditions.

I MILLSTONE - UNIT 2 3/4 4-19 Amendment No. N4,

FlA) 0-3 /*

2500 2000

• 1500 a-C,co Q

rc: 1 000 500 I

I Unaccptabl 8O0°F/hr r

rT

...I.

' I' II f.

I I1 I.

/

II III Ij I

I I

I I

P. -

I L.I 1 I.-

I - -

I.

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.. I I

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i II I

LL 0T-EO II a) 1>1

. E

.EL 1-j i

I.

..I.

I 2000F<T*275¶F I.

I 60°Flhr 700FsTs200TF

\\-

I I

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i 1-

. L-I 9

I.

- - - AI -

1----'---

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1, i

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I I- -

I-

-_-_L

=__

Min. Bolt-up lTemp = 70°F I

II-

-IF I

i I

I I

. 4 I

I I

L -

I f

1. -

I I

I Indicated Cold Lcg Maximum No.

Temperature of RCP's Operating T>.500F 4

2OOF <T S5OF l 3

_1-;

l170°FS~5TS5200°Pl2F r

]

I.

. Ig 1

.I t-0 50 100 150 200 250 300 350 400 450 500 550 Indicated Cold Leg Temperature (OF)

Millstone Unit 2 Reactor Coolant System Heatup Limitations for up to 54 EFPY Figure 3.4-2a

2000 S /

L 1*m I /unacceptase 1500 Ope on s

,,~~

• B s

iliv 0

t--P B-o-IjiP

-0

/

X

-:*e-t

..- t_ in.B t-.zp-

_i 0 50 0

1i0 0

4 ton Unit 2 MILLSTONE - UN1T 2 3/4 4-19b Amendment No.-HS8

Serial No.05-307 Docket No. 50-336 ATTACHMENT 3 PROPOSED REVISION TO TECHNICAL SPECIFICATIONS (LBDCR 05-MP2-003)

REACTOR COOLANT SYSTEM HEATUP/COOLDOWN LIMITS TECHNICAL SPECIFICATIONS RETYPED PAGES DOMINION NUCLEAR CONNECTICUT. INC.

MILLSTONE POWER STATION UNIT 2

2500

'i

• ~

.§ 1000F/hr 275°F<T!5630F 2000 Unacceptable 1500 Operation E

80°Flhr i

2000F<Ts275"F 1000

/

60°F/hr 70FsTs200F

\\

s l,

Lf, i

l l

Indicated Cold Leg Maxiimum No._.

500 T1'p-rlture o.RCPs opeating l..

T > 500'F 4

l-

,.*.1 *.

-. 9 200°F

< T s 50 F 3l

• Min. Bot-u 70T2 2

Temp 70'F 0

50 100 150 200 250 300 350 400 450 500 550 Indicated Cold Leg Temperature (OF)

Millstone Unit 2 Reactor Coolant System Heatup Limitations for Up to 54 EFPY Figure 3.4-2a MILLSTONE - UNIT 2 3/4 4-1 9a Amendment No. M1,

=-e pA,./

34

- 1J 7 J 2500 2000 S-%f.-0 1500 6.DI M

1000 C:

500 0

• I I 00°F/hr 220°F<T<5630 F Unacceptable Operation i.I. _

I*

l' l'.

T'

.-,:. f

~~~ 1

1t' II I..

'I' IJ

--,I 8

I I'

I--I I

I

-- L I_

..i II._

I:'-

I.

In In L

W)

'I Lo 11

.. tV 0E I_

I_

Is' I,..

Ij.

II'.

I I,.

J_.

r,.

.J _ _

50°F/hr 70°FcfT<220°F

-L.J I

- - 7 J

I.

I/

£

.-- I---

.-- i - -.

IL I

Z I

I II I

I I

- I-Maximum ndc No. of RCP' Tempeatre Operating T > 500°F 4

2 00<F<TS500F 3

150°FSTS200F 2

T < 150°F 0

I I

I I

I I

I 1

'--S------

I---'

I, I,

1 1

I 0

50 100 150 200 250 300 350 400 450 500 550 Indicated Cold Leg Temperature (OF)

Millstone Unit 2 Reactor Coolant System Cooldown Limitations for up to 54 EFPY Figure 3.4-2b

2500

,--r :

rT.

1I00°F/hr1 220 F<TS563*F 2000 L

Unacceptable Operation e

/

E 1500 1000 7r I

Maximum

..L

.Tempera W

ture No. of RCPs

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Millstone Unit 2 Reactor Coolant System Cooldown Limitations for Up to 54 EFPY Figure 3.4-2b MILLSTONE - UNIT 2 3/4 4-19b Amendment No. N,

Serial No.05-307 Docket No. 50-336 ATTACHMENT 4 PROPOSED REVISION TO TECHNICAL SPECIFICATIONS (LBDCR 05-MP2-003)

REACTOR COOLANT SYSTEM HEATUP/COOLDOWN LIMITS BASES MARKED-UP PAGES DOMINION NUCLEAR CONNECTICUT. INC.

MILLSTONE POWER STATION UNIT 2

REACTOR COOLAMT SYSTEM (F

July 1, 1998 BASES Reducing T to 4 515F prevents the release of activity should a steam generatorlube rupture since the saturation pressure of the primary coolant is below the lift pressure of the atmospheric steam relief valves. The surveillance requirements provide adequate assurance that excessive specific activity levels in the primary coolant will be vdetected in sufficient time to take corrective action.

Information obtained an Iodine spiking will be used to assess the parameters associated with iodine spiking phenomena. A reduction in frequency of isotopic analyses following power changes may be permissible if justified by the data obtained.

3/4.4.9 PRESSURE/IEMPERATURE LIMITS All components in the Reactor Coolant System are designed to with-stand the effects of cyclic loads due to system temperature and pressure changes. These cyclic loads are introduced by normal load transients, reactor trips, and startup and shutdown operations. The various categories of load cycles used for design purposes are provided in Section 4.0 of the FSAR.

During startup and shutdown, the rates of temperature and pressure changes are limited so that the maximum specified heatup and cooldown rates are consistent with the design assumptions and satisfy the stress limits for cyclic operation. In addition, during heatup and cooldown evolutions, the RCS ferritic materials transition between ductile and brittle (non-ductile) behavior. To provide adequate protection, the pressure/temperature limits were developed in accordance with the IOCFR50 Appendix 6 requirements to ensure the margins of safety against non-ductile failure are maintained during all normal and anticipated operational occurrences. These pressure/temperature limits are provided in Figures 3.4-2a and 3.4-2b and the heatup and cooldown rates are contained in Table 3.4-2.

During heatup, the thermal gradients In the reactor vessel wall produce thermal stresses which vary from compressive at the inner wall to tensile at the outer wall. These thermally induced compressive stresses Et I the inside wall tend to alleviate the tensile stresses induced by the internal I pressure. Therefore, a pressure-temperature curve based on steady state conditions (i.e., no thermal stresses) represents a lower bound of all similar curves for finite heatup rates when the inner wall of the vessel is treated as the governing location.

The heatup analysis also covers the determination of pressure-temperature limitations for the case in which the outer wall of the vessel becomes the controlling location. The thermal gradients estab-lished during heatup produce tensile stresses at-the outer wall of the vessel. These stresses are additive to the pressure induced tensile stresses which are already present. The thermally induced stresses at the outer wall of the vessel are tensile and are dependent on both the rate of heatup and the time along the heatup ramp; therefore, a lower bound curve similar to that described for the heatup of the inner wall cannot be defined. Subsequently, for the cases in which the outer wall of the vessel becomes the stress controlling location, each heatup rate of interest must be analyzed on an individual basis.

HILLSIOHE - UNIT 2 8 3/4 4-5 Amendment No. 218

CFor =v, YPtiA-ao r July 1, 1998 REACTOR COOLANT SYSTEM BASES The heatup and cooldown limit curves (Figures 3.4-2a and 3.4-2b) are composite curves which were prepared by determining the most conservative case, with either the inside or outside wall controlling, for any heatup or cooldown rates of up to the maximums described in Technical Specification 3.4.9.1, Table 3.4-2. The heatup and cooldown curves were prepared based upon I the most limiting value of the predicted adjusted reference temperature at the end of the service period indicated on Figures 3.4-2a and 3.4-2b.

Verification that RCS pressure and temperature conditions are within the limits of Figures 3.4-2a and 3.4-2b and Table 3.4-2, at least once per 30 minutes, is required when undergoing planned changes of ? 10F or a 100 psi.

This frequency is considered reasonable since the location of interest during cooldown Is over two inches (i.e. 1/4 t location) from the interface with the reactor coolant. During heatup the location of interest is over six inches from the interface with the reactor coolant. This combined with the relatively large heat retention capability of the reactor vessel ensures that small temperature fluctuations such as those expected during normal heatup and cooldown evolutions do not challenge the structural integrity of the reactor vessel when monitored on a 30 minute frequency. The 30 minute time interval permits assessment and correction for minor deviations within a reasonable time.

During RCS heatup and cooldown the magnitude of the stresses across the reactor vessel wall are controlled by restricting the rate of temperature change and the system pressure. The RCS pressure/temperature limits are provided in Figures 3.4-2a and 3.4-4b, and the heatup and cooldown rates are contained in Table 3.4-2. The following guidelines should be used to ensure compliance with the Technical Specification limits.

1. When changing RCS temperature, with any reactor coolant umps in operation, the rate of temperature change is calculated by using RCS loop cold leg temperature indications.

This also applies during parallel reactor coolant pump and shutdown cooling (SDC) pump operation because the RCS loop cold leg temperature is the best indication of the temperature of the fluid in contact with the reactor vessel wall. Even though SDC return temperature may be below KCS cold leg temperature, the mixing of a large quantity of RCS cold leg water and a small quantity of SDC return water will result in the temperature of the water reaching the reactor vessel wall being very close to RCS cold leg temperature.

2. When changing RCS temperature via natural circulation, the rate of temperature change is calculated by using RCS loop cold leg temperature indications.

3. When changing RCS temperature with only SDC in service, the rate of temperature change is calculated by using SDC return temperature indication.

MILLSTONE - UNIT 2 T 3/4 4-6 Amendment No. i.,

J11, 179. 218

July 1, 1998 REACTOR COOLANT SYSTEM r

ir'b~ii BASES

4. During the transition from natural circulation flow, to forced flow with SDC pumps, the rate of temperature change is calculated by using RCS loop cold leg temperature indications. SDC return temperature should be used to calculate the rate of temperature change after SOC is in

service, RBCCW flow has been established to the SDC heat exchanger(s), and SDC return temperature has decreased below RCS cold leg temperature.

'S.

During the transition from parallel reactor coolant pump and SDC pump operation, the rate of temperature change is calculated by using RCS loop cold leg temperature indications until all reactor coolant pumps are secured. SDC return temperature should be used to calculate the rate of temperature change after all reactor coolant pumps have been secured.

6.

The temperature change limits are for a continuous one hour period.

Verification of operation within the limit must compare the current RCS water temperature to the value that existed one hour before the current time. If the maximum temperature increase or decrease, during this one hour period, exceeds the technical Specification limit, appropriate action should be taken.

7. When a new, more restrictive temperature change limit is approached, it will be necessary to adjust the current temperature change rate such that as soon as the new rate applies, the total temperature change for the previous one hour does not exceed the new more restrictive rate.

The same principle applies when moving from one temperature change limit curve to another. If the new curve is above the current curve (higher RCS pressure for a given RCS temperature), the new curve will reduce the temperature change limit. It will be necessary to first ensure the new more restrictive temperature change limit will not be exceeded by looking at the total RCS temperature change for the previous one hour time period. If the magnitude of the previous one hour temperature change will exceed the new limit, RCS temperature should be stabilized to allow the thermal stresses to dissipate. This may require up to a one hour soak before ACS pressure may be raised within the limits of the new curve.

If the new curve is below the current curve (lower RCS pressure for a given RCS temperature), the new curve will allow a higher temperature change limit. All that is necessary is to lower RCS pressure, and then apply the new higher temperature change limit.

S. When performing evolutions that may result in rapid and significant temperature swings (e.g. placing 30C in service or shifting SDC heat exchangers), the total temperature change limit for the previous one hour period must not be exceeded. If a significant temperature change is anticipated, and an RCS heatup or cooldown is in progress, the plant should be stabilized for up to one hour, before performing this type of evolution. Stabiliking the plant for up to one hour will allow the thermal stresses, from any previous RCS temperature change, to dissipate.

This will allow rapid RCS temperature changes up to the applicable Technical Specification temperature change limit.

MILLSTONE - UNIT 2 B 3/4 4-6&

Amendment No. 218

REACTOR COOLAT SYSTEM BASES

'9. Additional marg n, to prevent exce ding the Appendix 6 limits when RCS temperature Is at or below 230'F,/can be obtained by Maintaining RCS pressure bel the pressure algl ed by the 50'f/hr oldown curve provided on igure 3.4-2b. Tb will ensure that af greater than anticipat temperature excur ion occurs duInn rt duration..

evolutio, the argins of fety required by pendix 6 vwil no be

/

exceeds i. Examples of p1 evolutions that result in una r cipated temperture excursions I lude placing SDC service without 1aral el RCP

ieraton, securin CPs when SDC is eady in service, s Ifting SDC hea exchangers, and itching SDC pumps Establishing a 1 r RCS p ssure, will mini e the probabilit of exceeding App lx G limits.

the r 0aF/hr vse m en aurve bes n teso evaluate unan i initieda tnl perature ext.

Ra1er an30td r to f c

nereon 3F/hr, theio Ril cooldown rate must be restorefo wrthin the 3 re c

as soon as te practical. Thb s may requere a soak perid to allu e thermal stresses, dsfrom the previous RCS temperat ur e hange, to diss1pate...

RTnDT; the results of these tests are shown In Table 4.6-1 of the Final Safety Analysis Report. Reactor operatiw n and resultent fast neutron nrradiation wil tcause an r

ncrease t n the RTNDT. Therefore, an adjusted reference temperature, based upon the fluenceen can be predicted using the methods described cn Revolbon 2 to Regulatory pu rde 1.99.

The heatup and cooldown nimft curves shown on Fioures 3.4-2a tnd 3.4-2b tnclude predscted adjustments for this shift 1n aRTiD at the end of the applicable service period, as well as adjustments for possible uncertainties an the pressure and temperature sensing instruments. The adjustments rnclude the pressure and temperature instrument and loop uncertarntbes assocrated with the maen control board displaysn the pressure drop across the core (RCP operation), and the eleration differences between the locatnin of the pressure transmitters and the vessel beltlne regilon. In addition to tshese curve adjustments, the LTOP evaluatlon tncludes adjustments due to valve stroke times, POR cspctraaty reactton times, and valve discharge backpressure.-

lthe actual sheft r

n RTNDT f the vessel matersal cs estableshed periodically during operation by removing and evaluating, in accordance with 10CFR50 Appendix H. reactor vessel material irradiation survetillance specimens installed near the inside wall of the reactor vessel in the core area. Since the neutron spectra at the irradiation samples and vessel inside radius are similar, the measured transition shift for a simple can be correlated to the adjacent section of the reactor vessel. The heatup and cooldown curves must be recalculated when the ARINDT determined from the surveillance capsule exceeds the calculated ARTNDT for the equivalent capsule radiation exposure.

The pressure-temperatu RLt lines shown on Figures 3.4-2a *nd7C.4-2b for reactor criticality lu n l-.E-...-.--

.~

haveOT been provided to assure comp iance with the mnlmlnum t emperature requirements s

of CFR 50 nticality Ni I )IF-ui

/ £1mnmn o

1 M11 I IWARF -

IINTT 17 R

/ &.hh Amendment No. 219

Insert C to Page B 3/4 4-6b For Inservice leak and hydrostatic testing, use of the heatup curve on Figure 3.4-2a and associated rates provide a conservative limit in lieu of a curve developed specifically for Inservice leak and hydrostatic testing. Therefore a separate leak and hydrostatic curve Is not explicitly included on Figure 3.4-2a

REACEOR COOLANT SYSTE3M BASES Ihe maximum RTNDT for all reactor coolant system pressure-retaining materials, with the exception of the reactor pressure vessel, bas been determined to be 500F. The Lowest Sorvico Temperature limit is based upon this RTNDT since Article NB-2332 (Summer Addenda of 1972) of Section m of the ASME Boiler and Pressure Vessel Code requires the Lowest Sevice Ttmporature to be RTNDjT + WO 0CF for piping, pumps and valves. Below this temperature, the.

sytem pressure must be limited to a maximum of 20% of the system's hydrostatic test pressure of 3125 pain. Operation of the RCS within the limits of the heatup and cooldown curves will ensure compliance with this requirement.

Included in this evaluation is consideration of flange protection in accordance with 10 CPR 50, Appendix Q The requirement makes the minimum temperature RTNDT plus 90IF for hydrostatic test and RTNDT plus 120'F for normal operation when the pressure exceeds 20 percent of the preservice system hydrostatic test pressure. Since the flange region RINDT has bj encalcula ed to bS 301F, the minimum flange pressurization temperature during normal operatiosn i 150°F W F with instrument uncertainty) when the pressure exceeds 20%/ of the preservice hydrostatic pressure. Operation of the RCS within the limits of the heatup and cooldown curves will ensure compliance with this requirement.

To establish the minimum boltup temperature, ASME Code Section XI, A jadix G.

requires the temperature of the Range and adjacent shell and head regions shall be above the limiting RT1 t= temperature for the most limmuiti of these regions. The RTNDT tenperature for that material is 30°F. Adding 1O§F, fdKmperature measurement uncertainty, results in a minimum boltup temperature of 4

.r additional conservatism, a minimum boltup temperature of 10°F is specified on the e~alid cooldown curves. The head and vessel flange region temperature must be greater tha 707F, whenever any reactor vessel stud is tensioned.

MILLSTONE - UNIT 2 B 3/4 4-7 Amendment No. 40, 40, 94, 24-, Z66,

Februmyl472OU5-REACTUR COlAT SYSM BASES The Low Temperature Overpressure Protection (LTOP) System provides a physical barrier against exceeding the IOCFRS0 Appendix 0 pressure/temperatire limits during low temprature RCS operation either with a steam bubble in the p rsurizr or during water solid conditioms. This system consists of either two POR (each PORV is equivalent to a vent of aproximately 1 squae Inches) with a pressure setpoint S 415 plal, or an RCS vent of sufficient sksc. Analysi-sha confirmed that the design basis mass addition transient discussed below will be mnitigateaby operation of the POR^V or by establishing an RCS vent of sufficient size.

The L1OP System is required to be OPERABLE when RCS cold log temperature is at or below 2751PF Cchnical Specification 3.4.93). However, If the RCS is in MODE 6 and the reactor vessel head has been removed a vent of sufficient size has been established such that RCS pressurization is pot possible. Therefore, an LTOP System is not rqed ical j

Ification 3.4.9.3 is not applicable).

2 3S;-;

VThe LTOP System Is armed at a temperature which exd limiting 1/4t lus Pe)WFusrequiredby,1PBG y(I..MR14 Ra AIh operatlng piod up toj!EFPY, the limiting 4tum LTOP System enable eeratur of at least e en con oren unce am The current value of 275 F will be retained.

The mass input analysis perofrmed to ensure P System is capable of protecting the reactor vessel assumes that all pumps capable of njecting into the RCS start, an then one PORV falls to actuate (single active failure). Since the PORs have limited relief capability, certain administrative restrictions have been implemented to ensure that the mass input transient will not exceed the relief capacity of a PORV. The anlysis has determined two PORVM (assuming one PORV fails) are sufficient if the mass addition transient is limited to the inadvertent start of one high pressure safety injection (HPSI) ump and two charging pumps when RCS temperature is at or below 2751F and above 1900°, and the inadvertent start of one charging pump when RCS temperature is at or below 190°F.

The assumed active failure of one PORV results in an equivalent RCS vent size of approximately 1.4 square inches when the one remaining PORV opens. Therefore, a passive vent of at least 1.4 square inches can be substituted for the PORMs. However, a vent size of at least 2.2 square inches will be required when VENTINO the RCS. If the RCS is depressurized and vented hrough ut bast a 2.2 square Inch vent, the peak RCS pressure, resulting from the maximum mass input transient allowed1y Tlechnical Specification 3.4.9.3, will not exceed 300 psig (SDC System suction aido design pressure).

When the RCS is at or below I 90°F, additional pumping capacity can be made capable of injecting into the RCS by establishing an RCS vent of at least 2.2 square inches. Removing a pressurizer PORV or the pressurizer manway will result in a passive vent of at least 2.2 square lnches. Additional methods to establish the required RCS vent are acceptable, provided the proposed vent has been evaluated to ensure the flow characteristics are equivalent to one of these.

Establishing a pressurizer steam bubble of sufficient size will be sufficient to protect the reactor vessel from the energy addition transient associated with the start of an RCP, provided the restrictions contained in Technical Specification 3.4.1.3 are met. These restrictions limit the heat MILLSTONE - UNIT 2 B 3/4 4-1a Amendment No. Mg, 04Ki-fP

Insert D to page B 3/4 4-7a Adjusted Referenced Temperature (ART) Is the RTNDT adjusted for radiation effects plus a margin term required by Revision 2 of Regulatory Guide 1.99.

Fc March 30,2000 REACTOR COATS@8 BANSE input bom the secondary system. They also ensure sufficient steam volume exists in the pressurizer to accommodate th insurge. No credit for PORV actuation was assumed in the LTOP analysis of the energy addition transient.

The restrictions apply only to the start of the irst RCP. Once at least one RCP is running, equllibrium Is achieved between he primary and secondary temperatures, eliminating any significant energy addition associated with the start of the second RCP.

The LTOP restrictions arm based on RCS cold leg temperature. This temperature will be determined by using RCS cold log temprature indication when RCPs are running, or natural circulation if it is occurring. Otherwise, SDC return temperature indication will be used.

Restrictions on RCS makeup pumping capacity are included in Technical Specification 3A.93. These restrictions are based on balancing the requirements for LTOP and shutdown risk.

For shudown risk reduction, It is desirable to have maximum makeup capacity ard to maintain the RCS full (not vented). However, for LTOP It is desirable to minimize makeup capacity and vent the RCS. To satisuIr these competing requirements, makeup pumps can be made not capable of injecting, but available at short notice.

A charging pump can be considered to be not capable of injecting into the RCS by use of any of the follc-;

ads and the appropriate administrative controls.

1. Placing the motor circuit breaker in the open position.

2. Removing the charging pump motor overload heaters from the charging pump circuit.

3. Removing the charging pump motor controller from the motor control center.

A HPS1 pump can be considered to be not capable of injecting into the RCS by use of any of the following methods and the appropriate administrative controls.

1. Racking down the motor circuit breaker from the power supply circuit.

2. Shutting and tagging the discharge valve with the key lock on the control panel (2-SI-654 or 2-SI-656).

3. Placing the pump control switch in the pull-to-lock position and removing the breaker control power fuses.

4. Placing the pump control switch in the pull-to-lock position and shutting the discharge valve with the key lock on the control panel (2-SI-654 or 2-SI-656).

These methods to prevent charging pumps and HPSI pumps from injecting into the RCS, when combined with the appropriate administrative controls, meet the requirement for two independent means to prevent pump injection as a result of a single failure or inadvertent single action.

MLLSTONE -UNIT 2 B 314 4-7b Amendment No. +8, 22, 243

RAoC I OR COL44N-Y REDACTOR COOLANT SYSTEM February 24, 2005 BASES These methods prevent inadvertent pump injections while allowing manual actions to rapidly restore the makeup capability if conditions require the use of additional charging or HPSI pumps for makeup in the event of a loss of RCS Inventory or reduction in SHUTDOWN MARGIN.

If a loss of RCS inventory or reduction in SHUTDOWN MARGIN event occurs, the appropriate response will be to correct the situation by starting RCS maup pumps. If the losw of Inventory or SHUIDOWN MARGIN is lgnflcant, this may necessitate the use of additional RCS makeup pumps that are being maintained not capable of injecting into the RCS In accordance with Technical Specification 3.4.9.3. The use of these additional pumps to restore RCS inventory or SHUTDOWN MARGIN will require entry into the associated ACTION statement. The ACTION statement requires immediate action to comply with she specification.

The restoration of RCS inventory or SHUTDOWN MARGIN can be considered to be part of the immediate action to restore the additional RCS makeup pumps to a not capable of injecting status.

While recovering RCS inventory or SHUTDOWN MARGIN, RCS pressure will be maintained below the Appendix G limits. After RCS inventory or SHUIDOWN MARGIN has been restored, the additional pumps should be immediately made not capable of injecting and the ACTION statement exited.

An exception to Technical Specification 3.0.4 is specified for Technical Specification 3.4.9.3 to allow a plant cooldown to MODE 5 if one or both PORVs are inoperable. MODE 5 conditions may be necessary to repair the PORV(s).

I 314.4.10 DELETED MILLSTONE -UNIT 2 B 3/4 4-7c Amendment No. *8, A, 24,

264, 04-MP2-016