ML20236K353

Safety Evaluation Supporting Amend 218 to License DPR-65

ML20236K353
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Site:	Millstone
Issue date:	07/01/1998
From:	NRC (Affiliation Not Assigned)
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ML20236K335	List: ML20236K330 ML20236K340 ML20236K353
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NUDOCS 9807090285
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p uooq p & UNITED STATES s* j NUCLEAR REGULATORY COMMISSION A" WASHINGTON, D.c. 2066H001

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I SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO.218 TO FACILITY OPERATING LICENSE NO. DPR-65 NORTHEAST NUCLEAR ENERGY._ COMPANY THE CONNECTICUT LIGHT AND POWER COMPANY THE WESTERN MASSACHUSETTS ELECTRIC COMPANY MILLSTONE NUCLEAR POWER STATION. UNIT NO. 2 DOCKET NO. 50-336

1.0 INTRODUCTION

By letter dated November 13,1997, as supplemented on December 29,1997, and April 8,1998, the Northeast Nuclear Energy Company, et al. (the licensee), submitted a request for changes to the Millstone Nuclear Power Station, Unit No. 2, Technical Specifications (TSs). The requested changes would modify TS 3.1.2.1, " Flow Paths - Shutdown;" TS 3.1.2.2, " Flow Paths -

Operating;" TS 3.1.2.3, " Charging Pump - Shutdown;" TS 3.1.2.4, " Charging Pumps - Operating;"

TS 3.1.2.5, " Boric Acid Pumps - Shutdown;" TS 3.1.2.6, " Boric Acid Pumps - Operating;"

TS 3.1.2.8, " Borated Water Sources - Operating;" TS 3.4.1.3, " Coolant Loops and Coolant Circulation - Shutdown;" TS 3.4.3, " Relief Valves;" TS 3.4.9.1, " Reactor Coolant System;"

TS 3.4.9.2, " Pressurizer;" TS 3.4.9.3, " Overpressure Protection Systems;" TS 3.5.3, "ECCS Subsystems - Tm < 300 'F;" and TS 3.10.3, " Pressure / Temperature Limitation - Reactor Criticality," and thir associated Bases in the areas that ara affected by the modified Low Temperature Overpressure Protection (LTOP) system, the updated reactor coolant system (RCS) pressure and temperature (P-T) curves and heatup and cooldown limits, and minor changes to correct various items, such as, updating of redundant or outdated TSs.

The proposed changes will ensure that the TSs, with their associated Bases, are consistent and conservative with respect to LTOP provided for the RCS, that the P-T limits are applicable up to 20 effective full power years (EFPY) of reactor operation and will also correct varicus items identified during a recent review of the current Millstone Unit 2 TSs. The December 29,1997, and April 8,1998, letters provided clarifying information that did not change the scope of the original Federal Register Notice (63 FR 4315, dated January 28,1998) or the initial proposed no significant hazards consideration determination.

9007090285 980701 PDR ADOCK 05000336 P PDR

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l 2.0 LTOP SYSTEM l 1

2.1 Background  !

The LTOP system mitigates overpressure transients at low temperatures so that the integrity of the reactor coolant pressure boundary is not compromised by violating the 10 CFR Part 50, Appendix G, P-T limits. Millstone Unit 2 LTOP uses the pressudzer power operated relief valves (PORVs) or an RCS vent with the reactor depressurized to accomplish this function. The system  ;

is manually enabled by operators and uses a single lifting setpoint for the PORVs. The design basis for Millstone Unit 2 LTOP considers both mass-addition and heat-addition transients. The mass-addition analysis accounts for the injection from one high pressure safety injection (HPSI) pump and two charging pumps when the RCS temperature is below 275'F and above 190'F.

! and the injection from one charging pump when the RCS temperature is below 190 F and above l 70*F. The mass-addition analysis assumes that the pressurizer is water solid and a maximum number of reactor coolant pumps (RCPs) running in various temperature ranges as specified in the proposed TS Figures 3.4-2a and 3.4-2b. The heat addition analyses account for heat input from the secondary side of the steam Oenerators into the RCS upon starting a single RCP when the secondary water temperature in each steam generator is less than 50'F above the RCS cold leg temperatures. The proposed TSs provide restricted plant operation within the configurations assumed in the analysis supporting the LTOP design.

The proposed LTOP enable temperature and the PORV actuation setpoint were established using methodology consistent with the guidelines contained in the NRC staffs Branch Technical {

Position (BTP) RSB 5-2. J 2.2 LTOP Requirements -

The proposed changes will relocate the LTOP requirements to TS 3.4.9.3. The proposed

. Limiting Conditions for Operation (LCOs) in TS 3.4.9.3 requires that an LTOP system, as discussed below, shall be operable when: (1) the RCS cold leg temperature is between 275 F and 190'F, with a maximum of two charging pumps and one HPSI pump capable of injecting into the RCS, two operable PORVs with a lift setpoint of 5 415 pounds per square inch absolute (psia) and; (2) when the RCS temperature is equal to or less than 190"F, either with a maximum

.of one charging pump capable of injecting into the RCS and two operable PORVs with a lift setpoint of 5 415 psia, or with a maximum of two charging pumps and one HPSI pump capable

- ofinjecting into the RCS with the RCS depressurized and an RCS vent of 2 2.2 square inches is available.

The staff has determined that relocating the LTOP requirements to TS 3.4.9.3 and the proposed changes to TSs 3.1.2.1, 3.1.2.3, 3.1.2.4, 3.4.1.3, and 3.5.3, including applicable surveillance requirements, to reflect the proposed LTOP system and restrict the plant operating configurations to be consistent with the design of the LTOP system are acceptable.

2.3: Enable Temperature The LTOP enable temperature is the temperature below which the LTOP system is required to be operable. The licensee utilized an LTOP enable temperature methodology which:

(1) accounts for instrument uncertainties associated with the instrumentation used to enable the LTOP system and, (2) implements the NRC staffs BTP RSB 5 2 by using an enable RCS water-temperature corresponding to a metal temperature of at least RTc + 90 F at the beltline

. location (1/4 thickness (1/4t) or 3/4 thickness (3/4t)). Therefore, the licensee calculated the j- ' enable temperature as rte + 90'F + temperature difference between RCS and metal +

l Instrument Uncertainties. Using the equation, the calculated limiting enable temperature is 262.7'F based on the 1/4t location. The licensee proposed an enable temperature of 275'F, .

which includes an additional margin of 12.3*F.

l The staff has determined that this proposed LTOP enable temperature is conservative with respect to the enable temperature alicwed by BTP RSB 5-2 and therefore, is acceptable.

I :2.4 LTOP Actuation Setpoint p The LTOP system is conservatively designed to mitigate overpressure transients at low temperatures to prevent violating 10 CFR Part 50, Appendix G, P-T limits during normal RCS  :

l heatup and cooldown evolutions.~ The LTOP actuation setpoint is the pressure at which the l

[ PORVs willlift, when the LTOP is enabled, to limit the peak RCS pressure dunng a pressurization transient.

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. The licensee proposed a PORV actuation setpoint of 415 psia that was calculated using a methodology described in the licensee's submittal. The staff has concluded that the l methodology produces conservative results and is acceptable. In response to the staff's request l for additional information, the licensee, in its letter dated April 8,1998, provided tabulations to l list the PORV setpoint, valve actuation uncertainty, hydraulic correction, peak reactor vessel' pressure, and the allowable reactor vessel pressure and margin available when the peak pressures occur for various limiting temperature conditions during heatup and cooldown when

' LTOP is required. The data presented in these tabulations confirm that the proposed PORV setpoint of 415 psia will provide adequate protection for the 10 CFR Part 50, Appendu G, P-T

.. limits including sufficient margin during a design basis overpressure transient (mass-addition or heat-addition) as descdbed in Section 2.1 of this report. '

The staff has determined that the proposed LTOP actuation setpoint for the PORVs will provide adequate protection for the P-T limits, including margin, during a design basis overpressure transient and therefore, is acceptable.

2.5 RCS Vent Size When the RCS cold leg temperature is below 190*F and the RCS is depressurized, the results of the licensee's analysis show that a vent size of 2.2 square inches is capable of mitigating the most limiting low temperature overpressure transient and maintain a peak pressure below the P-T limits. The analysis considered injection from one HPSI pump and two charging pumps, in addition to the mass injection due to pump operation, the energy input effects cf decay heat and energized pressurizer heaters were also included in establishing this minimum vert size. The licensee indicated that the vent size of 2.2 square inches could be achieved by tne rernoval of one PORV at Millstone Unit 2. The staff considers that the removal of a PORV from the pressurizer to create a RCS vent of 2.2 square inches when the RCS is depressurized is an acceptable means of protecting the P-T limits.

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The staff has determined that the method used for determ!aing the vent size is conservative and the proposed vent size is acceptable.

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. 2.6 LTOP Summary The staff has reviewed the licensee's proposed TS 3.4.9.3 including the licensee's analyses related to the proposed enable temperature of 275'F and actuation setpoint of 415 psia as discussed in Sections 2.3 and 2.4 of this evaluation. The licensee has considered instrument uncertainties in its setpoint calculation using the Instrument Society of America (ISA) S67.04-1994. The staff has determined that the licensee's analyses were performed in a manner consistent with approved methodology and that the results of the analyses conservatively demonstrates that the 10 CFR Part 50, Appendix G, P-T limits will be adequately protected with these setpoints and, therefore, the staff finds the proposed TS 3.4.9.3, including the surveillance requirements and associated TS Bases relating to LTOP, acceptable. In addition, the staff has also reviewed the proposed changes to TSs 3.1.2.1,3.1.2.3,3.1.2.4,3.4.1.3, and 3.5.3 affected by the change of LTOP system. The staff finds that these proposed TSs, including the surveillance requirements and associated TS Bases, sie consistent with the proposed LTOP system and provide adequate restrictions of plant operation to support LTOP and therefore, are acceptable.

3.0 P-T LIMITS i 3.1 Background The proposed changes to the P-T limits are intended to update the Millstone Unit 2 P-T curves for 20 EFPY using the latest vessel beltline material and fluence data. In addition, the licensee  ;

proposed changes to the associated TS Bases to support the updated P-T limits.

The staff evaluated the proposed changes to the P-T limits basted on the following NRC regulations and guidance: 10 CFR Part 50, Appendix G; Generic Letter (GL) 8811; GL 92-01, Revision 1; GL 92 01, Revision 1, Supplement 1; Regulatory Guide (RG) 1.99, Revision 2 (Rev. 2); and Standard Review Plan (SRP) Section 5.3.2. GL 88-11 advised licensees that the staff would use RG 1.90, Rev. 2, to review P-T limit curves. RG 1.99, Rev. 2, contains methodologies for determining the increase in transition temperature and the decrease in upper--

shelf energy (USE) resulting from' neutron radiation. GL 92-01, Rev.1, requested that licensees submit their reactor pressure vessel (RPV) data for their plants to the NRC staff for review. GL 92-01, Revi1, Supplement 1, requested that licensees provide and assess data from other licensees that could affect their RPV integrity evaluations. These data are used by the staff as the basis for the staffs review of P-T limit submittals, and as the basis for the staff's review of L pressurized thermal shock (PTS) assessments (10 CFR 50.61 assessmer.ts). Appendix G to 10 CFR Part 50 requires that P-T limits for the RPV be at least as conservative as those obtained by applying the methodology of Appendix G to Section XI of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (ASME Code). Section 50.55a specifies the addenda and edition of the ASME Code that is to be utilized by licensees in determining P-T limits.-

SRP 5.3.2 provides an acceptable method of calculating the P-T limits for ferritic materials in the be'lline of the RPV based on the linear elastic fracture mechanics methodology of Appendix G to the'1989 Edition of Section XI of the ASME Code. The basic parameter of this methodology is the Mress intensity facter K , which is a function of the stress state and flaw configuration. The methods of Appendix G postulate the existence of a sharp surface flaw in ths RPV that is normal

- to the direction of the maximum stress. This flaw is postulated to have a depth that is equal to

, one-fourth of the RPV beltline thickness and a length equal to 1.5 times the RPV beltline i

4 thickness. The critical locations in the RPV beltline region for calculating heatup and cooldown P-T limit curves are the 1/4t and 3/4t locations, which correspond to the depth of the maximum postulated flaw from the inside and outside surfaces of the RPV, respectively.

Part 50 of 10 CFR, Appendix G, requires that licensees determine the adjusted reference temperature (ART or RTwor) and the Charpy USE at the maximum postulated flaw depth. The delta RT is defined as the rum of the initial (unirradiated) reference temperature (initial RTuor),

the mean value of the adjustment in reference temperature caused by irradiation (delta RTuor),

and a margin (M) term. The delta RTuor is a product of a chemistry factor and a fluence factor.

The chemistry factor is dependent upon the amount of copper and nickel in the material and may be determined from tables in RG 1.99, Rev. 2, or from surveillance data. The fluence factor is dependent upon the neutron fluence at the maximum postulated flaw depth. The margin term is .

I dependent upon whether the initial RTsor is a plant-specific or a generic value and whether the l

chemistry factor was determined using the tables in RG 1.99, Rev. 2, or surveillance data. The margin term is used to account for uncertainties in the values of initial RTuor, copper and nickel L

contents, fluence, and calculational procedures. RG 1.99, Rev. 2, describes the methodology to ,

be used in calculating the margin term. '

3.2 Revised initial RTuor Values The licensee revised the initial RTwor values for almost all its beltline materials in its response to Gi 92-01, Rev.1, Supplement 1, and used the revised data in this submittal for determining '

P T limits. The initial RTuor is defined in paragraph NB-2331 of the ASME Code and depends upon the results of drop weight tests and Charpy V-notch tests. For plate material, the Charpy

tests must be performed on transversely oriented specimens. The current initial RTuor values for all beltline plates were basted on results of drop weight tests and Charpy curves from longitudinally oriented specimens. The longitudinal Charpy data was adjusted to simulate transverse data according to MTEB 5-2. ' A recent discovery of archive materials for C-505-1, C-505-2, and C-505-3 and the subsequent tests on these materials made the transverse Charpy curves also avai!able for these materials, as detailed in ABB Combustion Engineering Report, TR-MCC-276, dated June 1993. Further, Plate C-506-1 has Chayy curves for both specimen orientations from the surveillance program and a longitudinal Charpy curve from the original certified material test report. Weld 10137/3999 has drop weight test data and the Charpy curve from the surveillance program. Since De regulation requires the use of the transverse Charpy curve to determine the initial RTuor for plates, these new Charpy test data on transverse plate specimens can be used to revise the current initial RTuor values for these plates.

The licensee used the lowest of the three transverse plate Charpy values at two adjacent temperatures bracketing the Charpy energy 50 ft-lb. The licensee then employed linear interpolation to calculate the temperature T corresponding to the Charpy energy of 50 ft lb. The initial RTuor for the plate is defiried as the higher of T- 60'F and the nil-ductility transition temperature (NDT) from the drop weight test. The initial RTwot value for the surveillance weld was determined similarly. The staff listed in attached Table 1, the licensee's revised initial RTsor values, the values determined by the staff using NB 2331 and MTEB 5-2 without any interpolation, and the staff's bases for accepting the licensee's values. It should be noted that the licensee did nat adopt the plate initial RTuor values by the ABB Combustion Engineering Report, instead, it used the raw data provided in the report and developed its own values according to the procedure described above. For remaining beltline welds having only limited or no Charpy data, the staff listed in attached Table 2 the licensee's revised initial RTnor values, the licensee's bases, and the staff's bases for accepting or rejecting the revised values.

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4 The staff does not agree with the initial RTuoy of-80*F for Weld 8-203 (of heat no. 33A277) because this initial RTuor value is nonconservative when compared to data from other plants for this heat of weld. However, the ART for this weld using a generic initial RTsor of -56'F is less than the ART for the limiting material in the RPV. Hence, using a generic value will have no l Impact to the proposed P-T limits as discussed in Section 3.4 of this evaluation. l 3.3 Revised Chemistry Data i l

In addition to the initial RTuor values, the licensee also revised the copper and nickel values for almost all its beltline materids in its response to GL 92-01, Rev.1, Supplement 1, dated '

November 13,1995, and used the revised chemistry data in this submittal. The staff agrees only with the revisions for plates. The revised copper and nickel ulues for plates result in very small changes in the current plate chemistry factors. The largest reduction in plate chemistry factor is only 0.75. The changes in the licensee's revised copper and nickel values for welds are

, significant. These weld chemistry data, provided in its response to GL 92-01, Rev.1,

f. Supplement 1, were based on an in-house evaluation, which resulted in a significant increase of copper and nickel values for some welds and a significant decrease for others. Separately, the licensee participated in a Combustion Engineering Owner's Group (CEOG) effort, Report CE l NPSD 1039, Rev. 2, dated June 1997, to establish the best-estimate values for CE fabricated welds. The staff found that the licensee's proposed chemistry data for welds are different from l-those in the CEOG report. However, the staff had determined that using the higher chemistry data for welds will not increase their RTuor values beyond that associated with the limiting beltline plate; therefore, none of the welds will become the limiting beltline material due to the higher chemistry.

3.4 P-T Limits Evaluation The staff evaluated the effect of neutron irradiation embrittlement on each beltline materialin the reactor vessel of Millstone 2. - The staff determined that the limiting beltline material is the lower ,

.shell plate C-506-3.- This was based on the revised material data for all beltline materials and the chemistry factor method using surveillance data in accordance with RG 1.99, Rev. 2 (Surveillance Data) for Plate C-506-1. The licensee used the same material data but applied the chemistry factor method based on the Chemistry Factor Table in Section 1.1 of RG 1.99, Rev. 2, to all beltline materials. This approach resulted in a different limiting beltline material, the lower shell plate C-506-1. ABB Combustion Engineering Report, TR-MCC-276, dated June 1993, indicates that the chemistry factor for Plate C-506-1 based on Surveillance Data is about the same as that based on the RG Chemistry Factor Table. Using the surveillance data would lower the ART of Plate C-506-1 significantly because the margin would be 17'F instead of 34'F.

Nevertheless, the licensee conservatively used the Chemistry Factor Table to calculate the l

chemistry factor for Plate C-506-1, making it more limiting than Plate C-506-3. The staff has determined that the licensee's conservative approach is acceptable.- Using the higher chemistry data for welds will not make any of the welds more limiting.

To verify the licensee's P-T limits, the staff repeated the licensee's conservative approach by using the Chemistry Factor Table to evaluate all beltline plates and confirmed that the lower plate C-506-1 is limiting. The amount of irradiation embrittlement was calculated in accordance with RG 1.99, Rev. 2. The ART calculated by the staff at 20 EFPY for Plate C506-1, with 0.15 percent copper (Cu), 0.60% nickel (Ni), and an initial RTsor of 7*F, is 147.5 F at 1/41 and -

116.24*F at 3/4t. The ART was calculated at 20 EFPY based on a surface fluence linearly interpolated from the 32 EFPY surface fluence of 2AE19. 'The corresponding ART values

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.7 I calculated by the licensee using the Chemistry Factor Table are 145.0*F at 1/4t and 114.0'F at 3/4t. Both the staff and the licensee used the conservative approach of not including the cladding thickness in calculating the attenuation of the fluence through the vessel wall. 1 The ARTS calculated by the staff and the licensee are almost identical for the limiting material, Plate C-506-1. However, it should be noted that the licansee's calculation indicated a different limiting material for heatup curves. The licensee determined that Plate C-506-3 is limiting for heatup curves because its ART st 3/4t (114.5'F)is half a degree higher than that (114.0'F) for Plate C-506-1. However, in its evaluation, the staff considered Plate C 506-1 limiting for both heatup and cooldown curves for simplicity because the difference in the two ART values at 3/4t is negligible. ' Substituting the ART of 145.0'F at 1/4t and 114.5*F at 3/4t into equations in SRP 5.3.2, the staff verified the proposed P-T limit curves for heatup and cooldown. This

-verification was made only after the staff included the conservatism, which is unique to Millstone 2, in the P-T limits calculation. The unique features in the P-T limits of Millstone 2 consist of: (1) a temperature increase of 10.5'F to account for the uncertainty of the temperature indicator, (2) pressure decreases of 86.6 pounds per square inch (psi) (no RCP running),

115.5 psi (two RCPs are running), and 127.6 psi (three RCPs are running) to account for the pressure drop across the core and the uncertainty of the pressure indicator; (3) composite heatup and cooldown curve with different heatup and cooldown rates at different temperature ranges; and (4) pressure being expressed in " psia," with a value of 14.7 added to the gauge pressure. The detailed information regarding the P-T limits construction for Millstone 2 RPV is

, documented in its report, 97-SDS-1760-M2, which was provided in the December 29,1997, submittal. Hence, the staff confirmed the proposed P-T limits (for 20 EFPY) for heatup, cooldown, and hydro test and concluded that they meet the beltline material requirements in

. Appendix G of 10 CFR Part 50.

In addition to beltline materials, Appendix G of 10 CFR Part 50 imposes P-T limits based on the reference temperature for the reactor vessel closure flange materials.Section IV.A.2 of Appendix G refers to Table 1, which requires that when the pressure exceeds 20 percent of the preservice system hydrostatic test pressure, the temperature of the closure flange regions highly l stressed by the bolt preload must exceed the reference temperature of the materialin those regions by at least 120'F for normal operation and by 90'F for hydrostatic pressure tests and leak tests. Based on the limit:ng reference temperature of 30*F, the minimum allowable

temperature of this region is 150*F. As mentioned previously, the licensee added 10.5*F to

- 150*F to account for the temperature indicator uncertainty. These limits are shown as the straight-line segment on Figures 3.4-2b of the licensee's submittal. The straight line segment at

..the far left of the P-T limits was determined by another requirement specified in Table 1 of L Appendix G. Table 1 of Appendix G specifies that for pressure less than 20 percent of the preservice hydrostatic test pressure, minimum metal temperature in the stressed region should be at least the initial ART temperature for the material in the stressed regions. The temperature

. of 70*F in Figures 3.4-2a and 3.4 2b'of the submittalis conservative since adding the limiting reference temperature of 30'F to the temperature uncertainty of 10.5'F would yield a temperature lower than 70'F, Hence, the staff has determined that the proposed P-T limits j satisfy the requirements in Section IV.A.2 of Appendix G.

A correction was made to the system hydrostatic test curve in the submittal to pressurize the

- vessel along the heatup curve up to 271*F. This revised system hydrostatic test curve is more conservative than the current curve. The staff considered the corrected system hydrostatic test

!- curve adequate because it meets the requirement of Appendix G of 10 CFR Part 50, and the revised system hydrostatic test curve is consistent with the plant operating procedures. The i.

t 8-proposed changes to the Bases in the TSs are consistent with the proposed TS Figures 3 4-2a and 3.4-2b, and are also acceptable.

Appendix G further requires that the predicted Charry USE at end-of-license (EOL) for vessel beltline materials be above 50 ft-Ib or that licensees demonstrate that lower values of Charpy USE will provide margins of safety equivalent to those required by Appendix G of Section XI of the ASME Code. In its response to GL 92-01, Rev.1, Supplement 1, the licensee revised the initial USE values for almost all beltline materials. Except for Weld 9-203/3999 (heat no.10137),

Weld 9-203 (heat no. 90136), and the axial welds (heat no. A8746), all changes were insignificant. The staff examined the test data for Weld 9-203/3999 in BAW-2142. The staff does not agree that the initial USE for Weld 9-203/3999 should be increased from 130 ft-lb to l 133.3 ft-lb. ASTM E 185-79 specifies '"For specimens tested in sets of three at each test l temperature, the set having the highest average may be regarded as defining the upper shelf energy." However, since the licensee's data is in sets of two, the staff considered specimen Charpy energies at adjacent temperatures to the temperature that yielded the highest average energies and determined that the current value of 130 ft Ib is valid. The revised ini'.ial USE of 111 ft-lb for Weld 9 203 is acceptable because it is based on the 10*F Charpy d&ta, which is a very conservative approach. The revised initial USE of 83.5 ft lb for axial welds, has already been l approved by the staff in its Safety Evaluation dated September 25,1996.

The staff has determined, using the initial USE values acceptable to the staff for all beltline material, that all beltline materials have EOL USEs above 50 ft lb, and the Appendix G requirement on USE is satisfied.

L 3.5 P-T Limits Summary The staff concludes, based on the details in Section 3.4 of this evaluation, that the proposed ,

P-T limits for the RCS for heatup, cooldown, leak test, and criticality are valid as indicated on the curves. The P T limits satisfy the requirements of Appendix G of 10 CFR Part 50 for 20 EFPY.

The proposed P T limits also satisfy GL 88-11 because the method in RG 1.99, Rev. 2, was used to calculate the ART. Hence, the proposed P-T limits detailed in TS Table 3.4.2 and Figures 3.4-2a and 3.4 2b, including their associated LCOs and surveillance requirements, may be incorporated into the Millstone 2 TSs. The proposed changes to the Bases in the TSs are l

. consistent with the proposed P-T limits, and are also acceptable.

4.0 MISCELLANEOUS TS CHANGES

< The footnote for TS 4.1.2.2.c will be deleted because the required surveillance has been performed within the specified time period and the footnote is no longer applicable. The redundant wording stating that an operable pump be powered from an operable emergency bus in TSs 3.1.2.3 and 3.1.2.5 will be deleted because this requirement is covered in the definition of operable and the operability of the equipment covered by these TSs will not be affected.

Associated LCOs and surveillance will be modified to reflect currt.nl requirements and delete redundancy. TS 4.4.9.1.b will be deleted in that it is redundant to TS 4.4.1.5.

The scope of TS 3.1.2.6 will be expanded to cover all three flow paths identified in TS 3.1.2.2.a.

L The current requirements did not cover the flow path in TG 3.1.2.2.a.2. The change is necessary to meet the intent of the TS to cover all flow paths.

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. Clarification will be added to TS 4.1.2.8.d to be consistent with TS 4.1.2.7.c. The clarification will allow the boric acid storage tank temperature to be verified by checking the ambient air temperature.

I A note will be added to TS 3.4.3 to allow the block valve (s) to be cycled during plant cooldown when the block valve (s)is(are) closed due to inoperable power operated relief valves

( PORVs). The footnote will allow the PORV block valve (s) to be cycled during a plant cooldown to prevent thermal binding. This will ensure the associated block valve (s) can be opene , to allow the PORV(s) which is(are) inoperable to be manually cycled if necessary. Therefore, the PORV block valve (s) will be able to function as designed. The wording of TS 3.4.3.d will be revised to state what action should be performed and to remove specific details on how to perform the required action. This does not change the requirement of the action statement.

Therefore, the change will provide reasonable assurance that the pressurizer PORVs will continue to function as designed.

An action statement will be added to TS 3.4.9.3 to provide an 9xception to TS 3.0.4 requirements. This is necessary to allow a plant cooldown b '3DE 5 if one or both PORVs are inoperable. MODE 5 conditions may be necessary to repair 1,.c r>ORV(s).

A footnote will be added to TS 3.5.3 to allow entry into MODE 4 without an operable HPSI pump.

The new footnoto will allow the plant to enter MODE 4 where this specification is applicable without any operable HPSI pumps. However, this condition will only be allowed for a very short time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> or less. The proposed change to TS 3.4.9.3 will allow a HPSI pump to be operable above 190*F. However, the 10'F range before MODE 4 is reached may not allow sufficient time to ensure an HPSI pump is operable. Adding this note will provide sufficient time to make an orderly transition into MODE 4. This condition will only be allowed for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, which is the same time allowed by the first part of the associated action statement for an inoperable HPSI pump.

These proposed changes eliminate outdated or redundant TS requirements and references, and reflect the controls necessary to operate the facility within its design limits and are, therefore, acceptable.

5.0 OVERALL

SUMMARY

The NRC staff has determined that the proposed changes to TS Sections 3.1.2.1, " Flow Paths -

Shutdown;" TS 3.1.2.2, " Flow Paths - Operating;" TS 3.1.2.3, " Charging Pump - Shutdown;"

TS 3.1.2.4, " Charging Pumps - Operating;" TS 3.1.2.5, " Boric Acid Pumps - Shutdown;"

TS 3.1.2.6, " Boric Acid Pumps - Operating;" TS 3.1.2.8, " Borated Water Sources - Operating;"

TS 3.4.1.3, " Coolant Loops and Coolant Circulation - Shutdown;" TS 3.4.3, " Relief Valves;"

TS 3.4.9.1, " Reactor Coolant System;" TS 3.4.9.2, " Pressurizer;" TS 3.4.9.3, " Overpressure Protection Systems;" TS 3.5.3, "ECCS Subsystems - Ty < 300'F;" and TS 3.10.3,

" Pressure / Temperature Limitation - Reactor Criticality," and their associated Bases in the areas that are affected by the modified LTOP system, the updated RCS P T curves anc heatup and cooldown limits, and miscellaneous changes discussed in this evaluation are acceptable.

6.0 STATE CONSULTATION

in accordance with the Commission's regulations, the Connecticut State official was notified of the proposed issuance of the amendment. The State official had no comments.

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7.0 ENVIRONMENTAL CONSIDERATION

The amendment changes a requirement with respect to installation or use of a facility component

' ~

located within the restricted area as defined in 10 CFR Part 20 and changes surveillance l

requirements. The NRC staff has determined that the amendment involves no significant i increase in the amounts, and no significant change in the types, of any effluents that may be l

released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public i comment on such finding (63 FR 4315, dated January 28,1998). Accordingly, the amendment  ;

- meets the eligibility criteria for categor' cal exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to .

10 CFR 51.22(b) no environmental impact statement or environmental assessment need be i prepared in connection with the issuance of the amendment.

8.0 CONCLUSION

, ' The Commission has concluded, based on the considerations discussed above, that: (t) there is -

reasonable assurance that the health and safety of the public will not be endangered by l operation in the proposed manner, (2) such activities will be conducted in compliance with the

! Commission's regulations, and (3) the issuance of the amendment will not be inimical to the l

common defense and security or to the health and safety of the public.

Attachments: Tables 1 and 2 '

Principal Contributors: C. Liang S.Sheng Date: July 01, 1998

o Tabie 1. Basis for Accepting Licensee's Initial RTuor Values for Beltline Plates and Welds l

Where Test Charpy Curves Are Available ID Licensee's Initial RTuor without Staff's basis for accepting licensee's initial RTwo, Interpolation values using interpolation i Plates C-505-1 8.1 20.0 The lowest of the three Charpy data at 65 'F is 48 ft Ib. If this was 50 ft-lb, the initial RTuor would be 5'F. The Charpy curve indicates that by linear interpolation, the temperature of 68.1*F gives a Charpy energy of 50 ft-lb.

C-505-2 - 17,5 20.0 The lowest of the three Charpy data at i 80 F is 53 ft lb. If this was 50 ft lb, the I initial RTuor would be 20'F. The Charpy curve indicates that by linear interpolation, the temperature of 77.5 F gives a Charpy energy of 50 ft-lb.

C-505-3 5.0 5.0 no revision C-506-1 7.0 10.0 The lowest of the three Charpy data at 70 'F is 53.5 ft-lb. If this was 50 ft lb, the initial RTsor would be 10'F.. The Charpy curve indicates that by linear interpolation, the temperature of 67.0'F

~. .: gives a Charpy energy of 50 ft Ib, C-506-2 -18.3 -20.0 revised to a more conservative value C-506-3 13.2 0.0 revised to a more con::ervative value Welds J 10137/3999' -56.3 50 The lowest of the three Charpy data at 10*F is '77 ft lb. If this was 50 ft-Ib, the initial RTnor would be 50'F, The Charpy curve indicates that by linear i interpolation, the temperature of 3.7*F gives a Charpy energy of 50 ft Ib.

Implication of data from other olants:

A survey of RVID indicated that only Fermi 2 and Hatch 2 reported higher values ( 50'F) for welds of this Heat.

Since this value was derived from 10 F data using the GE methodology, the value of 56.3*F is acceptable.

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l o-l l-Table 2. Basis for Accepting Licensee's initial RTuor Values for Beltline With Limited or No Test Data ID Licensee's Licensee's basis Staff's basis for accepting or rejecting initial RTuo, licensee's values 33A277 -80.0 Calvert Cliffs data Not acceotable although no revision was requested. ,

lmolication of data from other clants:

A survey of RVID indicated that the

)

1 initial RTuo7 values for. welds of this Heat range from -80'F to -50 F. The licensee should consider data from all i plants, not just the data from Calvert }

Cliffs. l l

90136 -50.0 From three 10*F data Acceptable. It is in accordance with 1 NB2331 and involves no extrapolation ')

from the three 10'F data. -

Implication of data from other olants:

A survey of RVID indicated that this conservatively determined value is the highest among all reported values for . j welds having the same Heat.

(

A8746 -56.0 Generic data. Using Acceptable. Although the initial RTnor the three 10 F data for this weld can be conservatively of 65,75, and 78 ft lb estimated to be 50 F from the three is too conservative 10'F data, the fact that the three Charpy data are much higher than 50 ft-Ib indicates that the true value is several j degrees lower than 50"F. '

lmolication of data from other plants:

No other plants have weld with Heat no.

A8746 and Linde 124 flux. Using the '

generic value is appropriate.

)

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!l l

'O Millstone Nuclear Power Station i Unit 2 cc:

Lillian M. Cuoco, Esquire Mr. F. C. Rothen Senior Nuclear Counsel Vice President - Work Services Northeast Utilities Service Company Northeast Utilities Service Company P. O. Box 270 P. O. Box 128

Hartford, CT 061410270 Waterford, CT 06385 Mr. John Buckingham Ernest C. Hadley, Esquire Department of Public Utility Control 1040 B Main Street Electric Unit P.O. Box 549

.10 Liberty Square West Wareham, MA 02576 New Britain, CT 06051 Mr. John F. Streeter l Mr. Kevin T. A. McCarthy, Director Recovery Officer - Nuclear Oversight Monitoring and Radiation Division Northeast Utilities Service Company Department of Environmental Protection P. O. Box 128.

79 Elm Street Waterford, CT 06385 Hartford, CT 06106-5127 Mr. David B. Amerine

- Regional Administrator, Region i Vice President - Human Services U.S. Nuclear Regulatory Commission Northeast Utilities Service Company 475 Allendale Road P. O. Box 128

. King of Prussia, PA 19406- Waterford, CT 06385 First Selectmen . Mr. Allan Johanson, Assistant Director Town of Waterford Office of Policy and Management Hall of Records Policy Development and Planning 200 Boston Post Road Division I Waterford, CT 06385 - 450 Capitol Avenue - MS# 52ERN P. O. Box 341441 Mr. Wayne D. Lanning Hartford, CT 061341441 Deputy Director of Inspections Special Projects Office Mr. M. H. Brothers 475 Allendale Road Vice President Operations King of Prussia, PA 19406-1415 Northeast Nuclear Energy Company P.O. Box 128 Charles Brinkman, Manager Waterford, CT 06385 Washington Nuclear Operations ABB Combustion Engineering Mr. J. A. Price 12300 Twinbrook Pkwy, Suite 330 Director - Unit 2 Rockville, MD 20852 Northeast Nuclear Energy Company P.O. Box 128 Senior Resident inspector Waterford, CT 06385 Millstone Nuclear Power Station c/o U.S. Nuclear Regulatory Commission P.O. Box 513 Niantic, CT 06357 {

1

c l 0 l Millstone Nuclear Power Station I' Unit 2 cc:

Mr. B. D.- Kenyon (Acting) Attomey Nicholas J. Scobbo, Jr.

Chief Nucler Officer- Millstone Ferriter, Scobbo, Caruso, Rodophele, PC Northeast Nuclear Energy Company 1 Beacon Street,11th Floor P.O. Box 128 Boston, MA 02108 Waterford, CT 06385 Mr. J. P. McElwain Citizens Regulatory Commission Recovery Officer - Millstone Unit 2 '

ATTN: Ms. Susan Perry Luxton Northeast Nuclear Energy Company 180 Great Neck Road P. O. Box 128 Waterford, CT 06385 Waterford, Connecticut 06385 Deborah Katz, President Citizens Awareness Network P. O. Box 83 Shelbume Falls, MA 03170 The Honorable Terry Concannon Co-Chair-Nuclear Energy Advisory Council Room 4035 i Legislative Office Building .

Capitol Avenue .

Hartford, CT 06106 Mr. Evan W. Woollacott )

l Co-Chair Nuclear Energy Advisory Council 128 Tony's Plain Road Simsbury, CT 06070 Little Harbor Consultants, Inc.

Millstone - ITPOP Project Office i P, O. Box 0630 l Niantic, CT 06357-0630 '

Mr. Daniel L. Curry Project Director Parsons Power Group Inc.

2675 Morgantown Road Reading, PA 19607 Mr. Don Schopfer Verification Team Manager Sargent & Lundy 55 E. Monroe Street Chicago,IL 60603 i