Text

Application for Amend to License DPR-65,changing TSs 3.1.2.1,3.1.2.2,3.1.2.3,3.1.2.4,3.1.2.5,3.1.2.6,3.1.2.8, 3.4.1.3,3.4.3,3.4.9.1,3.4.9.2,9.4.9.3,3.5.3 & 3.5.3,re RCS Heatup/Cooldown Limits & LTOP
	ML20199D455
Person / Time
Site:	Millstone
Issue date:	11/13/1997
From:	Bowling M; NORTHEAST NUCLEAR ENERGY CO.
To:	; NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20199D460	List: B16809, Proposed Tech Specs Re Reactor Coolant Sys Heatup/Cooldown Limits & Low Temp Overpressure Protection; ML20199D455;
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	B16809, NUDOCS 9711200339
	Download: ML20199D455 (44)
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nei, rerry na. (mote isea watera. er oo383 Northeast OOI U57 Mdistone Nuclear Powr Station Northeast Nuclear liergy Gunpany P.0 Bus 128 Waterford, CT 06385-0128 (860) 447 1791 Fat (860) 444 $277

'The Northeast Utilitice Systern NOV t 3 p m Docket No. 50-336 B16809 Re: 10CFR50.90 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 Millstone Nuclear Power Station, Unit No. 2 Proposed Revision to Technical Specifications Reactor Coolant System Heatup/Cooldown Limits and Low Temperature Overpressure Protection Introduction Pursuant to 10CFR50.90, Northeast Nuclear Energy Company (NNECO) hereby proposes to amend Operating Liconse DPR-65 by incorporating the attached proposed changes into the Technical Specifications of Millstone Unit No. 2. NNECO is proposing to change Technical Specifications 3.1.2.1, " Flow Paths - Shutdown," 3.1.2.2, " Flow Paths - Operating," 3.1.2.3, " Charging Pump - Shutdown," 3.1.2.4, " Charging Pumps -

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

Operating," 3.1.2.8, " Borated Water Sources - Operating," 3.4.1.3, " Coolant Loops and Coolant Circulation - Shutdown," 3.4.3, " Relief Valves," 3.4.9.1, " Reactor Coolant System," 3.4.9.2, " Pressurizer," 3.4.9.3, " Overpressure Protection Systems," 3.5.3, "ECCS Subsystems - Tavg < 300 *F," and 3.10.3, " Pressure / Temperature Limitation -

Reactor Criticality." Information will be added to the Bases of the associated Technical Specifications to address the proposed changes.

The proposed change to Technical Specification Section B 3/4.5.2 and 3/4.5.3 is ea the same page (B 3/4 5-2) which has been proposed to be changed in separate letters dated November 3,1995', which addressed the allowed outage time of an Emergency

' E. A. DeBarba letter to the NRC, " Millstone Nuclear Power Station, Unit No. 2 Proposed Technical Specification Revision Emergency Core Cooling Subsystem Allowed Outage t t'

Time Extension," dated November 3,1995.

/ M 9711200339 9f111 b, PDR ADOCK 05000336 p PDR

6.S. Nuclear Regul: tory Commission B16809/Page 2 Core Cooling subsystam, and September _ 2,1997', which addressed compliance issues. The proposed danges contained in this letter do not assume approval of any of the previously submitted changes.-

Attachment 1 provides a discussion of- the proposed changes and the Safety Assessment. Attachment 2 provides the Significant Hazards Consideration.

Attachment 3 provides the marked-up version of the appropriate pages of the current .

Technical Specifications. Attachment 4 provides the retyped pages of the Technical Specifications. ,

Environmental Considerations NNECO has reviewed the proposed license amendment request against the criteria of 10CFR51.22 for environmental considerations. The proposed changer modify the Reactor Coolant System heatup and cooldown limits and Low Temperature Overpressure Protection requirements. These changes do not increase the type and amounts of effluents that may be released off site. In addition, this amendment request ,

will not significantly increase individual or cumulative occupational radiation exposures.

Therefore, NNECO has determined the proposed changes will not have a significant effect on the quality of the human environment.

Conclusions The proposed changes wa e evaluated utilizing the criteria of 10CFR50.59 and were determined not to be an u, reviewed safety question. Additionally, we have concluded the proposed changes are safe.

The proposed changes do not involve a significant impact on public health and safety (see the Safety Assessment provided in Attachment 1) and do not involve a Significant Hazards Consideration pursuant to the provisions of 10CFR50.92 (see the Significant Hazards Consideration provided in Attachment 2).

Plant Operations Review Committee and Nuclear Safety Assessment Board The Plant Operations Review Committee and Nuclear Safety Assessment Board have reviewed and concurred with the determinations.

Schedo!e We request issuance at your earliest convenience, with the amendment to be implemented within 60 days of issuance.

2 y, L. Bowling, Jr. letter to the NRC, " Millstone Nuclear Power Station, Unit No. 2 Proposed Revision to Technical Specifications Compliance issues," dated September 2,1997.

0.S. Nuclear Regul tory Commission

- B16809/Page 3 State Notification in accordance with 10CFR50.91(b), a copy of this License Amendment Request is being provided to the State of Connecticut.

- if you should have any questions on the above, please contact Mr. Ravi Joshi at (860) 440-2080.

Wy truly yours, NORTHEAST NUCLEAR ENE RGY COMPANY Martin L. Bowling, Jr. i/

Millstone Unit No. 2 - Rec 6/ery Officer Sworn to and subscribed before me this \ D_ day of kbe mbf- .1997

~hwd%we \d$4htw e .

Nhtary Pubic d

My Commission expires hha.on y Attachments (4) cc: H. J. Miller, Region 1 Administrator D. G. Mcdonald, Jr., NRC Senior Project Manager, Millstone Unit No. 2 D. P. Beaulieu, Senior Resident inspector, Millstone Unit No. 2 W. D. Travers, Ph.D, Director, Special Projects Office W. D. Lanning, Deputy Director of Inspections - Special Projects Office P. F. McKee, Deputy Director of Licensing - Special Projects Office Director Bureau of Air Management Monitoring and Radiation Division Department of Environmental Protection 79 Elm Street Hartford, CT 06106-5127

1 . , :.

1 Docket No 50-336 B16809 i Attachment 1 Millstone Nuclear Power Station, Unit No. 2 Proposed Revision to Technical Specifications

Reactor Coolant System 'r'7atup/Cooldown Limits -

and Low Temperature Overpressure Protection Discussion of Proposed Changes November 1997 4.

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0 U.S. Nuclear Regulatory Commission

816809/Atta& ment 1/Page 1 ;

Proposed Revision to Technical Specifications

- Reactor Coolant System Heatup/Cooldown Limits l and Low Temperature Overpressure Protection

- Discussion of Proposed Changes ;

,1 Introduction Northeast Nuclear _ Energy Company (NNECO) is proposing to change Technical j Specifications 3.1.2.1, " Flow Paths - Shutdown," 3.1.2.2, " Flow Paths - Operating,"-

3.1.2.3, " Charging Pump - Shutdown," 3.1.2.4, " Charging Pumps - Operating," 3.1.2.5,

" Boric Acid Pumps - Shutdown,' 3.1.2.6, ' Boric Acid Pumps - Operating," 3.1.2.8, "Borsted Water Sources - Operating," 3.4.1.3, " Coolant Loops and Coolant Circulation -

Shutdown," 3.4.3, ' Relief Valves," 3.4.9.1, " Reactor Coolant System," 3.4.9.2,

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Pressurizer," 3.4.9.3, " Overpressure Protection Systems," 3.5.3, "ECCS Subsystems -

Tavg < 300 *F," and 3.10.3, " Pressure / Temperature Limitation - Reactor Criticality." -!

Information will be added to the Bases of the associated Technical Specifications to address the proposed changes.

The major changes proposed will modify the low temperature overpressure protection (LTOP) requirements and Reactor Coolant System (RCS) heatup and cooloown limits. -

Additional minor changes have been proposed to correct various items identified during .

the review of the Millstone Unit No,2 Technical Specifications. Each proposed change is discussed. Additional background information is included, as necessary. to explain the changes. Related changes are grouped together. However, the marked up pages contained in Attachment 3 are sequenced in numerical order by page nember.

- LTOP Chances A new analysis to ensure the 10CFR50 Appendix G limits are met has been performed This new analysis has identified that changes are necessary to the current Technical Specification requirements to ensure the resultant RCS pressure increase due to mass and energy addition transients will not exceed the 10CFR50 Appendix G limits. The proposed changes include a reduction in LTOP power operated relief valve (PORV) setpoint from 450 psig to 415 psia (400 psig), additional mass input restrictions, aM more restrictive reactor coolant pump (RCP) start criteria.

The current LTOP requirements are located in three sections of the Millstone Unit No. 2 Technical Specifications; Reactivity Control Systems, Reactor Coolant System, and Emergency : Core Cooling - Systems. Also located in these three sections are requirements to ensure the validity of the boro., dilution accident analysis (maximum of-

[ two charging pumps operable in Modes 4, 5 and 6) and to ensure sufficient RCS

' makeup capability is maintained. The proposed changes described below will modify and. relocate the LTOP requirements to just one Technical Specification, 3.4.9.3,

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U. S. Nucl:ar Regul tory Commission B16809/ Attachment 1/Page 2

' Overpressure Protection Systems." Boton dilution requirements will not be changed.

RCS makeup requirements will be modified as necessary to be consistent with the LTOP mass input requirements. The consolidation of the LTOP mass input requirements is consistent with the new Standard Technical Specifications for Combustion Engineering plants (NUREG-1432).

The current LTOP mass input restrictions allow a maximum of two charging pumps (Technical Specification 3.1.2.4) and one high pressure safety injection (HPSI) pump (Technical Specification 3.5.3) to be operable and capable of injecting into the RCS when the RCS temperature is below 275 *F. When RCS temperature is reduced below 200 *F a maximum of one charging pump and one HPSI pump (Technical Specification 3.1.2.3) are allowed to be operable and capable of injecting. An additional charging pump and HPSI pump can be capable of injecting provided the RCS is vented through a passive vent that is t 2.8 in'.

The proposed changes to the LTOP mass input requirements will still allow a maximum of two charging pumps and one HPSI pump to be operable and capable of injecting below 275 'F. However, when RCS cold leg temperature is at or below 190 *F, only one charging pump will be allowed to be operable and capable of injecting if the PORVs are being used for LTOP. A maximum of two charging pumps and one HPSI pump may be capable of injecting at or below 190 F if an RCS passive vent of g 2.2 in*

is established for LTOP.

Reactor coolant pump (RCP) starting requirements associated with the energy input LTOP transient will remain in Technical Specification 3.4.1.3, " Coolant Loops and Coolant Circulation Shutdown." However, changes to these restrictions will be made.

Each LTOP related change is described below.

1. Technical Specification 3.1.2.1, "Boration Systems Flow Paths - Shutdown,"

Limiting Condition for Operation (LCO) b. will be modified to remove the words

'and a high pressure safety injection pump." A HPSI pump will no longer be required to be operable in Modes 5 and 6. This change is consistent with the proposed LTOP mass input requirements when RCS temperature is below 190 F (Technical Specification 3.4.9.3).

2. Technical Specification 3.1.2.3, " Charging Pump - Shutdown," will be modified to address only the minimum requirements for RCS makeup. The LTOP requirements currently contained in this specification will be relocated to Technical Specification 3.4.9.3. The proposed changes to this specification are:

a. Revise the LCO to require at least one charging pump to be operable. A HPSI pump will no longer be required to be operable in Modes 5 and 6. A maximum of two charging pumps will be allowed to be capable of injecting into the RCS. This chang 3 is consistent with the assumption of two

U. S. Nuclear Regulatory Commission B16809/ Attachment 1/Page 3 charging pumps used in the boron dilution accident analysis and the LTOP mass input requirements (Technical Specification 3.4.9.3). Also, the requirement for the cperable charging pump to be powered from an operable emergency bus will be removed. This is redundant wording to the definition of operable and can"be removed without affecting any operability requirements.

b. Delete the "" and associated footncte. This footnote is not necessary since the proposed change will only require one charging pump to be operable in Modes 5 and 6.

c. The words "One additional charging pump and high pressure safety injection pump may be capable of injecting provided that the RCS is vented through a passive vent of 2 2.8 in'." will be removed. The proposed LTOP mass input requirements contained in Technical Specification 3.4.9.3 will allow for this combination as long as a sufficient passive vent is established,

d. Modify. Technical Specification Action Statement (TSAS) a to only address the condition of no operable charging pumps. This is consistent with the proposed changes to the LCO previously discussed.

e. Modify TSAS b to address the condition of more than two charging pumps capable of injecting into the RCS. Thit is consistent with the proposed changes to the LCO previously discussed,

f. Modify Surveillance Requirement (SR) 4.1.2.3.1 to remove the high pressure safety injection pump and emergency bus electrical requirements. This is consistent with the proposed changes to the LCO previously discussed.

g. Modify SR 4.1.2.3.2 to verify one charging pump is not capable of injecting into the RCS. The word " inoperable" will be replaced with "not capable of injecting into the RCS." This more accurately addresses the boron dilution analysis restriction of limiting the dilution flow to two charging pumps since an inoperable pump can still inject into the RCS.

This change is consistent with the boron dilution accident analysis.

h. Relocate SR 4.1.2.3.3 to Technical Specification 3.4.9.3 as SR 4.4.9.3.3.

The purpose of this SR is to verify the mass input restrictions for LTOP protection are met. LTOP restrictions will only exist in LCO 3.4.9.3.

Therefore, it is appropriate to relocate this SR.

i. Relocate SR 4.1.2.3.4 and associated footnote "" to Technical Specification 3.4.9.3 as SR 4.4.9.3.4. The purpose of this SR is to verify

l U. S. Nuclear Regulatory Commission l

B16809/ Attachment 1/Page 4 the venting requirements for LTOP protection are -met. LTOP requirements will only exist in LCO 3.4.9.3. Therefore, it is appropriate to -

relocate this SR. The footnote will be incorporated in the SR.

3. The proposed changes to Technical Specification 3.1.2.4 are:

a. The

and associated footnote will remain. This footnote is not needed -

to allow compliance with Technical Specification 3.4.9.3 (current conflicting requirement is' contained in Technical Specification 3.1.2.3) since the proposed change to tlw LTOP requirements will allow the second charging pump to be operable above 190 'F. However, this 10 F range beforo Mode 4 is reached does not allow sufficient time to ensure the second charging pump and one HPSI pump (Technical Specification 3.5.3) are operable. Retaining this note will provide the operating crew sufficient time to make an orderly transition to Mode 4.

The reference to Technical Specification 3.1.2.3 will be changed to Technical Specification 3.4.9.3 to be consistent with the ploposed changes to the LTOP requirements. A similar note will be proposed for Technical Specification 3.5.3.

b. Modify the TSAS to add a designation of "a." TSAS b will be added to address more than two charging pumps capable of injecting into the RCS in Mode 4. This coridition must be corrected immediately (consistent with the time to correct a similar situation in Technical Specification 3.1.2.3).

This is consistent with the current LCO.

c. Modify SR 4.1.2.4.2 to verify one charging pump is not capable of injecting into the RCS. The word " inoperable" will be replaced with "not capable of injecting into the RCS." This more accurately addresses the boron dilution analysis restriction of limiting the dilution flow to two charging pumps since an inoperable pump can still inject into the RCS.

This change is consistent with the boron dilution accident analysis.

d. Modify the footnote (**) by replacing the word " operable" with " capable of injecting into the RCS." This more accurately addresses the boron dilution analysis restriction of limiting the dilution flow to two charging pumps since an inoperable pump -can still inject into the RCS. This change is consistent with the boron dilution accident analysis.

4. The requirements to start an RCP contained in the footnote (**) to Technical Specification 3.4.1.3 will be modified. The new criteria will ensure that starting an RCP will not result in an energy addition transient that could exceed the 10CFR50 Appendix G limits. The requirements to start the first RCP apply only when the RCS is below 275 'F. Below this temperature, LTOP is requirea by Technical Specification 3.4.9.3. This is consistent with the current requirements.

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, ; U. 8. Nuclear Regulatory Commission.

816809/ Attachment 1/Page 5 -

i When any RCS cold leg temperature is 5275 'F, it will be necessary to ensure a !

steam bubble of sufficient size in the pressurizer, ensure RCS: pressure is; consistent with the analysis assumptions, and minimize the delta-T between' thel RCS and the secondary system. If these limr . Ans are met, the energy addition

' from starting an'RCP_ will not result in anl excessive RCS pressure increase.~

These limitations are not necessary if at least one RCP is already operating.:

With at least one RCP operating, RCS flow will be sufficient to ensure that the primary and secondary sido of each steam generator are at essentially the same temperature.

The addition of a restriction on pressurizer pressure is consistent with the new -

LTOP ' analysis. The units used to express the required pressurizer water - -)

1

-volume will be changed from cubic feet to % level to agree with control room indication. The required values for pressurizer water level and pressure do not include an adjustment for the instrument uncertainty associated with control l room indication. This adjustment will be made to the values contained in the l procedures that will be used to start an RCP.

The delta-T limit will not specify a separate value based on the use of a surface contact instrument. Only one value will be specified. This value does not include an adjustment for instrument uncertainty. This adjustment wit be made '

to the value contained in the procedures that will be used to start an RCP, The Bases for tlils specification will be revised to discuss how this delta-T can be determined.

5. - Technical Specification 3.4.9.3, "Overprecsure Protection Systems," will be revised to- include' mass input restrictions in addition to the pressure relief / venting requiremente already specified. This is consistent with the general format used in NUREG-1432.

a. The LCO will be revised to differentiate the requirements based on RCS temperature. - The requirements will change when RCS cold leg temperature is at or below 190 'F. These requirements are consistent with the new LTOP analysis as previously discussed,

b. The LTOP PORV setpoint will be reduced from 450 psig to 415 psia (400 psig). The 50 psi reduction in PORV setpoint is necessary to ensure the 10CFR50 Appendix G limits are not exceeded. The change in units from "psig" to " psia"_ is consistent with control room indications.

c. The applicability wi!! be increased by removing _ *and the RCS is not vented through a 2.8 square inch or _ larger vent." Therefore, this specification wili be app!! cable unless the reactor vessel head has been -

L removed, or RCS temperature is above 275 *F.

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U. S. Nuclear Regulatory Commission

. B16809/ Attachment 1/Page 6

d. TSASs a, b, and c will be modified by ' adding the word " required" before PORV.: This will ensure ~these TSASs will only be applied when the q PORVs are providing LTOP.. '

e.- ' TSASs a, b,: and c will be ' modified to require a 2.2 in'. vent instead of; j either a .1.4 or 2.8 in' vent, A passive _ vent is normally established by removing a pressurizer PORV, pressurizer safety. valve, or the pressurizer manway.- The value of 2.2 in' is the minimum size of vent that will ensure RCS pressure remains s 300 psia, which is more conservative than the

=

Appendix G limits. This. vent size will_ also ensure that RCS pressure does not exceed the Shutdown Cooling-(SDC) System design pressure. ,

in addition, this is the size of vent that will satisfy Technical.Specif* cation -

3.4.9.1 to allow a 50 'F/hr cooldown rate below 190 'F. This change is consistent with the passive venting requirements contained in the LCO.

f. Editorial changes to the wording of TSASs a, b, and c will be made. The technical requirements will remain the same,

!- g. TSAS d will become SR 4.4.9.3.4. The requirements currently contained i

in the TSAS require periodic verification of plant conditions, they do not establish plant conditions. Therefore, the requirements should be contained in an SR. SR 4.4.9.3.4 will also replace SR 4.1.2.3.4, which will be deleted as previously discussed. Minor wording changes will be made. However, the technical requirements will remain the same. This change is consistent with NUREG 1432.

h. A new TSAS d will be added to provide the required action if the mass input requirements contained in the LCO are exceeded. An immediate response is appropriate to correct this situation. This is consistent with the action requirements contained in LCOs 3.1.2.3 and 3.1.2.4. This change is consistent with NUREG 1432.

1. SR 4.4.9.3.2 will be added - to verify the mass input requirements contained in the LCO are met. This SR will replace SR 4.1.2.3.2, which will be modified as previously discussed to ensure one charging pump is not capable of injecting for boron dilution requirements. SR 4.4.9.3.2 will allow one or two charging pumps to be capable of injecting, depending on RCS temperature and passive vent size. :This change is consistent with NUREG 1432c

. J. SR .4.4.9.3.3 will be added- to verify the mass input requirements contained-in the LCO are- met. This SR will replace SR 4.1.2.3.3 (previously discussed) and SR 4.5.3.2 (discussed later). This SR will use the term "not capeble of injecting" instead of " inoperable." Verifying a ,

U. S. Nuclear Regul: tory Commission B16809/ Attachment iiPage 7 pump is inoperable is not sufficient to ensure it is not capable of injaction.

Since the intent of this SR is to ensure the mass input assumed in the LTOP analysis is valid, the wording change is appropriate. This change is consistent with NUREG 1432.

7. Technical Specification 3.5.3, "ECCS Subsystems - Tavg < 300 *F," will be revised to remove the LTOP mass input restriction. This restriction will be relocated to Technical Specification 3.4.9.3, " Overpressure Protection Systems,"

as discussed previously,

a. The words "As a minimum, one" will be replaced with "One" in the LCO.

This is an editorial chan0e only. LCO 3.5.3 will still require a minimum of one ECCS subsystem to be operable.

b. The "#" and associated footnote will be removed from the LCO. This restriction will be covered by the LCO for Technical Specification 3.4.9.3, as previously discussed.

c. An """ and new footnote will be added to the LCO. This new footnote 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 period, one hour. The proposed change to Technical Specification 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 a HPSI pump is operable. Adding this note will provide the operating crew sufficient time to make an order ly transition into Mode 4. This condition will only be allowed for one hour, which is the same time allowed by the TSAS a. A similar note already exists for the charging pump requirements specifiet by Technical Specification 3.1.2.4.

d. TSAS c will be relocated to Technical Specification 3.4.9.3 as the new TSAS d. The purpose of this action statement is to ensure the mass input requirements for LTOP protection are met. LTOP requirements will only exist in LCO 3.4.9.3. Therefore, it is appropriate to relocate this action statement.

e. SR 4.5.3.2 will be relocated to Technical Specification 3.4.9.3 as SR 4.4.9.3.3. Ine purpose of this SR is to verify the mass input requirements for LTOP protection are met. LTOP requirements will only exist in LCO 3.4.9.3 Therefore, it is appropriate to relocate this SR.

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U. S, Nucisar Regulatory Commission B16809/ Attachment 1/Page 8 i

Heatuo and Cooldown Chances A new analysis has been performed to develop new RCS pressure / temperature curves and heatup and cooldown 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. This need was identified during the review of the 1995' and 1996 r heatup/cooldown events which resulted in violation of the current Technical Specification requirements.

The new analysis includes additional allowances not contained 10 the current analysis.

These additional allowances include instrument uncertainties, pressure adjustments between the location of the pressure instrumentation and the limiting vessel beltline region, and adjustments for the copper and nickel content in the reactor vessel.

Figure 3 4.2 will be replaced by two curves, Figures 3.4-2a and 3.4-2b. The temperature change limits will be located in the new Table 3.4-2, instead of in the LCO.

The new limits will use cold leg temperature instead of average temperature to dote mince when to change rates. There should be little difference between these two temperatures, and cold leg indication is directly available to the control room operators.

This is consistent with the new analysis.

The proposed curves and rates are based on indicated cold leg temperature. This paramoter, which is, the best available indication of reactor vessel downcomer temperature, will normally be monitored by using either RCS cold leg temperature indication or SDC return temperature. Plant conditions will determine which one is the appropriate indication to use. Actual RCS cold lag temperature will be used if any RCP is operating or natural circulation is occurring. Otner#,se, SDC return temperature will be used.

' D. B. Miller, Jr. letter to the U.S. Nuclear Regulatory Commissicn Millt'one Nuclear Power Station, Unit No. 2, Licensee Event Report (LER)95-030 00, %lation of Technical Specification 3.0.4 During Reactor Plant Heatup,' dated AugJst 22,1995.

' D. B. Miller, Jr. letter to the U.S. Nuclear Regulatory Commission, Mi!'. stone Nuclear Power Station, Unii No. 2, Licensee Event Report (LER) 96-00100,

Reactor Coolant System Heatup Rate Exceeded Technical Specification Limit,' dated January 30,1998 P. M. Richardson letter to the U.S hiear Regu% tory Commission, Millstone Nuclear Power Station, Unit No. 2, Licensee Event Report (LER)96-007 00

Reactor Coolant System Cooldown Rate Exceeded Technical Specification Umit,' dated March 22,1996.

P. M. Richardson letter to the U.S. Nuclear Regulatory Commissan, Millsto.m Nuclear Power Station, Unit No. 2, Ucensea Event Report (LER) 96-00101,' Reactor Coolant System Heatup Rate Exceeded Technical Specification Limit,' dated June 27,1996.

U. S. Nuclear Regulatory Commission B16809/ Attachment 1/Page 9 Figure 3.4 2a will address plant heatup. The heatup limits, which will be contained in Table 3.4 2, have been changed as a result of the new analysis. The minimum reactor vessel bolt-up temperature, the minimum temperature for criticality, and the hydrostatic and leak test limit will be located on Figure 3.4 2a. Also, RCP restrictions, assumed in the development of the heatup curves, will be added.

Figure 3.4 2b will address plant cooldown. The cooldown limits, which will be contained in Table 3.4 2, have been changed as a result of the new analysis. Two cooldown curves will available when RCS temperature is 5 230 'F. The minimum reactor vessel bolt-up temperature and the minimum temperature for criticality will be located on Figure 3.4 2b. Also, RCP restrictions, assumed in the development of the cooldown curves, will be added.

The use of the proposed RCS pressure / temperature and heatup/cooldown limits is covered in more detail in the addition to the Bases of Technical Specification 3.4.9.1.

Each RCS heatup and cooldown related change is described below.

1. Revise the wording of Technical Specification 3.4.9.1 LCO to reference Figures 3.4-2a and 3.4-2b, instead of Figure 3.4 2. Figure 3.4.2 will be replaced by two curves, Figures 3.4-2a and 3.4-2b. The LCO will also reference Table 3.4-2 which will contain the heatup and cooldown rates.

2. Delete 'during heatup, cooldown, criticality, and inservice leak and hydrostatic testing with:' from the LCO for Technical Specification 3.4.9.1. Heatup and cooldown will be retained in the modified LCO. Criticality limits, which are addressed by Technical Specification 3.1.1.5, ' Minimum Temperature for Criticality," will not be retained in the LCO. (See the discussion below concerning SR 4.4.9.1.b.) Inservice leak and hydrostatic testing will be contained in Table 3.4 2, which is discussed below.

3. The temperature change limits currently specified in Technical Specification 3.4.9.1.a and b will be modified and relocated to Table 3.4-2. Changes to these limits will be discussed later.

4. The temperature change limit currently specified in Technical Specification 3.4.9.1.c will be relocated to Table 3.4 2. This current wording will be modified (clarification only) to specify the limit applies for one hour prior to the start of inservice leak and hydrostatic testing. This wording will also be modified to replace "above system design pressure" with "above the heatup limit curve' and to apply the temperature restrictions to inservice leak and hydrostatic testing, instead of just hydrostatic testing. Inservice leak and hydrostatic testing is performed above the normal system operating pressure. It is not done above system design pressure (2500 psla). Therefore, the current wording is not

U. S. Nuclear Regulctory Commission B16809/ Attachment 1/Page 10 i

correct. Also, the inservice leak and hydrostatic testing limit will be located only on the heatup limit curve.

5. The applicability of Technical Specification 3.4.9.1 will be expanded. Concern for non-ductile failure of the reactor vessel and flange applies at all times.

Therefore, the applicability will be expanded to address this. This change is consistent with NUREG 1432.

6. The current TSASs for Technical Specification 3.4.9.1 will be modified. The TSASs will be separated by mode,

a. in Modes 1 through 4, the 30 minute time period for limit restoration will remain the same A time limit of 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months will be placed on the performance of the engineering evaluation. If this evaluation is not performed in this time period, or the evaluation does not allow continued operation, the plant will be required to enter Mode 5 ($ 200 *F), instead of the current requirement to be < 200 *F. This slight relaxation will have no significant impact on plant operations because plant temperature is not normally maintained at the mode change limit. Also, defining plant condition by mode, instead of by pressure and temperature, is consistent with the action requirements of most Technical Specifications.

b. The required RCS pressure will be reduced from 500 psia to 300 psia.

This change will require plant conditions that are closer to the actual plant 4 conditions in Mode 5. Operation of the Shutdown Cooling System

(administrative limit on RCS pressure of 265 psla) and the proposed LTOP System PORV setpoints 5 415 psia require RCS pressure to be below the current 500 psia Ilmit. Also, establishing a lower RCS pressure will result in less pressure stress on the reactor vessel,

c. In other than Modes 1 through 4, immediate action will be required for limit restoration. Violation of these limits is typically more severe when the RCS is cold (< 200 *F), therefore an immediate response is appropriate. A time limit of prior to entering Mode 4 will be placed on the performance of the engineering evaluation. This will prevent plant startup until the evaluation has determined that the RCS is acceptable for continued operation.

These changes are consistent with NUREG-1432.

7. SR 4.4.9.1.a will be modified to require verification that RCS pressure and temperature are within limits every 30 minutes, instead of once per hour. This more restr;ctive change will provide the plant operators with earlier indication that a limit roay be exceeded, so that action can be taken to prevent exceeding the limit. This change is consistent with NUREG-1432.

. . l U. 8. Nuclear Regulatory Commission B16000/ Attachment 1/Pagc 11

8. SR 4.4.9.1.b will be deleted. SR 4.4.9.1.b is redundant to SR 4.1.1.5 of l Torhnical Specification 3.1.1.5, " Minimum Temperature For Criticality." This ;

redundancy is not necessary to ensure compliance with the limit. This change is consistent with NUREG-1432. {

9. SR 4.4.9.1.c will be renumbered as 4.4.9.1.b to account for the deletion of SR l 4.4.9.1.b. Also, this SR will be modified to reference Table 3.4 2, Figure 3.4-2a, -

and Figure 3.4 2b instead of Figure 3.4 2.

10. Figure 3.4.2 will be replaced by two curves, Figures 3.4-2a and 3.4 2b. The '

temperature change limits will be contained in the new Table 3.4 2, instead of in

the LCO. 7hs new limits will use cold leg temperature instead of everage temperature _to _ determine when to change rates. There should be little ;

difference between these two temperatures, an<1 cold leg indication is directly available to the control room operators. This is consistent with the new analysis. -

4 Figure 3.4 2a will address plant heatup. The bootup limits, which will be !

contained in Table 3.4-2, have been changed as a result of the new fracture ,

mechanics analysis. The minimum reactor vessel bolt-up temperature, the minimum temperature for criticality, and the hydrostatic and leak test limit will be ;

located on Figure 3.4 2a. Also, RCP restrictions, assumed in the development of the heatup curves, will be added.

Figure 3.4-2b will address plant cooldown. . The cooldown limits, which will be ,

contained in Table 3,4-2, have been changed as a result of the new fracture mechanics analysis. Two cooldown curves will be available when RCS- .

temperature is below 230 'F. The minimum reactor vessel bolt-up temperature and the minimum temperature for critica!ity will be located on Figure 3.4 2b.

Also, RCP restrictions, assumed in the development of the cooldown curves, will be added. -

L F

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1 U. S. Nuclear Regulatory Commission i B16809/ Attachment 1/Page 12 l

The old and new limits are summarized in the table below. The use of the proposed RCS pressure / temperature and heatup/cooldow' limits is covered in more detail in the addition to the Bases of Technl:al Specification 3.4,9.1.

1 CURRENT PROPOSED Heatup Heatup RCS Temperature Limit Indicated Cold Leg Limit (Tavg) Temperature 5110*F 20 *F / hour 5220'F 5 30 'F / hour 110 'F < T S 140 *F 30 'F / hour 220 *F < T 5 275 'F 5 50 'F / hour

> 140 'F 50 'F / hour > 275 'F 5100 'F / hour Cooldown Cooldown RCS Temperature Limit Indicated Cold Leg Limit (Tavo) Temperature 5120*F 5 'F / hour $ 100 *F $ 5 'F / hour if RCS not vented 120 'F < T 5 200 'F 20 'F / hour 100 *F < T s 230 'F s 30 'F / hour if RCS not vented 200 'F < T 5 300 'F 30 'F / hour < 190 *F 5 50 'F / hour if RCS vent > 2.2 square inches 5230'F 5 50 *F / hour During unanticipated temperature excursions

> 300 *F 80 *F l hour > 230 *F 5 80 *F / hour Hydrostatic Testing Hydrostatic Testing Limit Limit 5 *F / hour s 5 *F / hour For 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months prior to and during inservice hydrostatic and leak testing operations above the heatup limit curve.

11. The current action requirements for the Pressurizer, Technical Specification 3.4.9.2, will be modified to be consistent with the proposed changes to Technical Specification 3.4.9.1. The wording of the purpose of the engineering evaluation will be changed from " fracture toughness properties of the pressurizer" to

U. S. Nuclear Regulatory Commission B16809/ Attachment 1/Page 13 1

structural integrity of the pressurizer.' This wording is consistent with Tecnnical Specification 3.4.9.1 and NUREG-0212, " Standard Technical Specifications for Combustion Engineering Prescurized Water Reactors.' A time limit of 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months will be placed on the performance of the engineering evaluation. If tho evaluation is not performed in this time period, or the evaluation does not allow continued operation, the plant will be required to enter Mode 3 within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and reduce pressure to below 500 psia within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months . The required RCS pressure will be reduced from 500 psig to 500 psla. This change in pressure units is consistent with plant instrumentation and other Technical Specifications. Also, establishing a lower pressure will result in less pressure stress on the pressurizer.

12. SR 4.4.9.2 will be modified to require verification that pressurizer temperature and spray water temperature differential are within limits every 30 minutes, instead of the current once per hour requirement. This more restrictive change will provide the plant operators with earlier indication that a limit may be exceeded, so that action can be taken to prevent exceeding the limit. This change is consistent with the proposed changes to SR 4.4.9.1.a.

13. Revise the wording of Technical Specification 3.10.3, Action Statement b., and SR 4.10.3.1 to reference Figures 3.4-2a and 3.4 2b, instead of Figure 3.4-2.

Figure 3.4.2 will be replaced by two curves, Figures 3.4-2a and 3.4-2b, as previously discussed.

14. SR 4.10.3.1 will be modified to require verification that RCS pressure and temperature are within limits every 30 minutes, instead of the current once per hour requirement. This more restrictive change will provide the plant operators with earlier indication that a limit may be exceeded, so that action can be taken to preveat exceeding the limit. This change is consistent with SR 4.4.9.1.a.

Other Chances

1. SR 4.1.2.2.c will be modified to remove the "* and associated footnote. The time period covered by this footnote has passed. Therefore, this footnote can not be used and should be removed.

2. Technical Specification 3.1.2.5 will be modified to remove the requirement for the operable boric acid pump to be powered from an operable emergency bus.

This is redundant wording to the definition of operable and can be removed without affecting any operability requirements. The LCO will be modified, SR 4.1.2.5.d will be deleted, and SR 4.1.2.5.b and SR 4.1.2.5.c will be modified accordingly. Also the word "above," will be removed. Technical Specification 3.1.2.1a is not above, it is on a separets pago. This is an editorial change only.

l U. S. Nuclear Regulatory Commission i B16809/ Attachment 1/Page 14

3. Technical Specification 3.1.2.6 LCO will be modified to change ' pumps (s)* to i

pump (s).' The first 's' is redundant and can be removed without affecting the intent of the LCO. l The TSAS for 3.1.2.6 will also be modified. The word 'one" will be replaced by

'the' and *(s)* will be added to " pump." These changos are necessary to allow the TSAS to apply to the flow path covered by Technical Specification 3.1.2.2.a.2. Each boric acid flow path covered by Technical Specificatlun 3.1.2.2.a.2 is described below,

s. Technical Specification 3.1.2.2.a.1 flow path requires one boric acid storage tank (BAST), the associated gravity feed valve, and the associated boric acid pump to be operable. For this flow path, the loss of the gravity feed valve, or the boric acid pump, will still allow the contents of the BAST to be available. The current TSAS for 3.1.2.6 would apply to this flow path if the associated boric acid pump was inoperable.

b. Technical Specification 3.1.2.2.a.2 flow path requires the combined capacity of two BACTs, two gravity feed valves, and two boric acid pumps to be operable. For inis flow path, the loss of both gravity feed valves, or both boric acid pumps, will still allow the contents of the BASTS to be available. The current TSAS for 3.1.2.6 would not apply to this flow path if both associated boric acid pumps were inoperable. However, the loss of the two boric acid pumps for this flow path is equivalent to the loss of one boric acid pump for the other two flow paths. Therefore, the TSAS should apply.

c. Technical Specification 3.1.2.2.a.3 flow path requires two BASTS, each with the required capacity, the associated gravity feed valve for one of the tanks to be operable, and the associated boric acid pump for the other tank to be operable. For this flow path, the loss of the gravity feed valve, or the boric acid pump, will still allow the contents of the other BAST to be available. The current TSAS for 3.1.2.6 would apply to this flow path if the associated boric acid pump was inoperable.

4. SR 4.1.2.8.d will be modified to allow the BAST temperature to be verified by checking the ambient air temperature. This is currently allowed by SR 4.1.2.7.c.

This provision was added to Technical Specification 3.1.2.7 by Amendment No.

133'. The NNECO submittal

also wanted to change SR 4.1.2.8.d to be D. H. Jaffe letter to E. J. Mroczka, License Amendment No.133 to Facility Operating License DPR 65, dated October 11,1988.

E. J. Mroczka letter to U.S. Nuclear Regulatory Commission, ' Millstone Nuclear Power Station, Unit No. 2, Proposed Revision to Technical Specifications. Boric Acid Concentration Reduction,"

dated April 29,1988.

U. S. Nuclear Regul: tory Commission B16809/ Attachment 1/Page 15 consistent with SR 4.1.2.7.c, however the retyped pages submitted by NNECO did not contain the entire sentence. Therefore, it was not added to SR 4.1.2.8.b.

5. Add a footnote (*) to Technical Specification 3.4.3, Action Statement a. This TSAS applies when the PORVs are inoperable but capable of being manually cycled. The footnote will allow the PORV block valve (s) to be cycled during a plant cooldown to prevent thermal binding This will ensure the PORV(s) which is(are) inoperable, can be manually cycled if necessary. .

6. Revise the wording of Technical Specification 3.4.3, Action Statement d, to state what action should be performed, and to remove specific details on how to perform the required action. The Bases for this specification will be expanded to include a discussion of possible methods to accomplish the required action, in addition, the current wording is not correct because there is no "close" position associated with the main control board PORV control switches.

7. A new TSAS f will be added to Technical Specification 3.4.9.3. This action statement, which states the provisions of Technical Specification 3.0.4 are not applicable, is necessary to allow a plant coo!down to MODE 5 if one or both PORVs are inoperable. MODE 5 conditions may be necessary to repair the PORV(s).

5 This provision was removed by Amendment No.151. However, a review of the Technical Specifications has identified that Technical Specification 3.0.4 would prevent plant entry into the LTOP region (RCS cold leg temperature < 275 'F) unless the requirement of Technical Specification 3.4.9.3 for two operable PORVs is met. This proposed change will allow a plant shutdown to Mode 5 to proceed, if necessary to repair the inoperable PORV(s).

This change is consistent with the old Standard Technical Specifications for Combustion Engineering plants (NUREG-0212). The new Standard Technical Specifications for Combustion Engineering plants (NUREG-1432) does not include this provision for the appropriate LTOP specification (3.4.12). The wording of Specification 3.0.4 in NUREG-1432 states "or other specified condition in the Applicability for an unlimited period of time." Therefore, it is not necessary to include this exemption.

G. S. Vissing letter to E. J. Mroczka, Ucense Amendment No.151 to Facility Operating License DPR-65, dated February 26,1991.

U. 8. Nuclear Regulatory Commission B16809/ Attachment 1/Page 16 Bases Changes c The Bases of the'affected Technical Specifications will be expanded to discuss these sanges. In addition, &anges will be made as necessary to correct unrelated items. ,

Each change will be listed by page number and briefly discussed. l r

1. Page B 3/412 :

The word ' gallons' will be added just after 15,000. This is an editorial change. !

2. Page B 3/413 l The word ' OPERABLE" will be replaced with ' capable of injecting into the RCS' to be consistent with the proposed changes to Technical Specifications 3.1.2.3 l and 3.1.2.4. The discussion concerning pumping capacity- and LTOP ,

requirements will be relocated to the Bases of LTOP Technical Specification .

3.4.9.3.

3. Page B 3/41-3a l

The reference to Technical Specification 3.1.2.3 will be changed to Technical Specification 3.4.g.3. The word ' OPERABLE' will be replaced with

capable of

. injecting into the RCS" and the RCS temperature requirement for only one l charging pump to be capable of injecting will be added. These changes are consistent with the proposed changes to Technical Specification 3.4.g.3. i

4. Page B 3/4 4-1 The discussion concerning RCP start requirements will be modified to be consistent with the proposed changes. An explanation of the requirements and how to verify compliance will be added. This will include the instrumentation to use and how to account for instrument accuracy,

5. Page B 3/4 4-2 The discussion concerning the PORV(s) will be modified to be consistent with the proposed changes and to provide clarification. This specification addresses the PORVs requirements for operation in Modes 1,2, and 3. It does not address LTOP considerations, which are addressed by Technical Specification 3.4,g,3.

In addition, a brief discussion of how to prevent the PORV(s) from opening automatically will be added.

4 4

-an , ,. :,,,-.,-w, , . _ _ _ . _ , , , . . , . . _ , , , . , _ _ _ _ _ . . _ . . . _ _ _ _ - _ _ _ _ _ _ _ _________._____-________._l

l U. S. Nuclear Regulatory Commission B16809/ Attachment 1/Page 17

)

6. Page B 3/4 4-2a The discussion concerning the PORV(s) will be modified to be consistent with I the requirements of Technical Specification 3.4.3. This specification addresses i the PORV(s) requirements for operation in Modes 1, 2, and 3. It does not address LTOP considerations, which are addressed by Technical Specification 3.4.9.3.

7. Pages B 3/4 4 5, B 3/4 4-6, and B 3/4 4-7 The discussion concerning RCS pressure / temperature limits (heatup and cooldown curves) will be modified to be consistent with the proposed changes.

Additional information concerning the fracture mechanics analysis will be added.

The Bases will be expanded to provide operational guidance to ensure the plant is operated in accordance with the requirements of Technical Specifications, 3.4.9.1 and 3.4.9.2. This will include a discussion of how to calculate the rate of temperature change, what instrumentation to use for various plant equipment configurations, and when to apply the various limits.

8. Page B 3/4 4 7 The discussion concerning LTOP will be modified to be consistent with the proposed changes. Additionalinformation concerning the LTOP analysis will be added.

The Bases will be expanded to discuss RCS makeup capacity and how to ensure the makeup pumps are not capable of injecting. This will include the compromise necessary between LTOP requirements and shutdown risk concerns of adequate RCS makeup capacity. A discussion of the appropriate instrumentation to use will also be added.

9. Page B 3/4 5-2 The Bases will be expanded to discuss the exemption to Technical Specifications 3.0.4 and 4.0.4 that will be added to Technical Specification 3.5.2.

Safety Assessment The proposed changes will modify the RCS pressure / temperature limits, heatup and cooldown limits, and the LTOP requirements. The majority of the proposed changes are being made as a result of the new pressure / temperature and LTOP analyses performed. The new pressure / temperature curves and 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

i U. S. Nuclear Regulatory Commission B1GB09/ Attachment 1/Page 18 Review Plan Section 5.3.2. The new LTOP mass input and RCP starting rr .ctions and LTOP PORV setpoints are consistent with the criteria contained in the Standard Review Plan Section 5.2.2. Additional changes have been proposed to correct variouc items identified during the review of the Millstone Unit No. 2 Technical Specifications.

The specific details of each proposed change have already been presented. This Safety Assessment will group the proposed changes into four categories and then evaluate their safety significance. The four categories are LTOP Changes, RCS Heatup and Cooldown Changes, Boron Dilution Changes, and Other Changes.

LTOP Changes

1. Technical Specifications 3.1.2.1 and 3.1.2.3 will no longer require a high pressure safety injection (HPSI) pump to be operable in Modes 5 and 6.

The current Millstone Unit No. 2 Technical Specifications require one charging pump and one HPSI pump to be operable in Modes 5 and 6 (the HPSI pump is not required when the reactor vessel head has been removed). The proposed change will only require one charging pump to be operable in Modes 5 and 6.

When the plant is in Mode 5 or 6 there are two major factors to consider with respect to the number of RCS makeup pumps required to be operable, if too many RCS makeup pumps are required, an inadvertent start of these pumps can result in a mass addition transient beyond the capacity of the LTOP System.

This may result in an RCS pressure increase that exceeds the 10CFR50 Appendix G pressure / temperature limits. An excessive number of charging pumps can also affect the plant response during a boron dilution accident.

The minimum number of RCS makeup pumps required to be operable in Modes 5 and 6 ensures sufficient makeup capability is available for RCS boration requirements and RCS inventory control. The RCS is required to be borated to a sufficient boron concentration to ensure the Technical Specification Shutdown Margin (SDM) requirements are met. The appropriate SDM requirements must be met before entry is allowed into Mode 5 or 6. RCS boron concentration is increased to establish the required SDM. This is normally accomplished by adding borated water to the RCS during plant cooldown to compensate for the contraction of the RCS inventory. The proposed change will restrict the number of pumps available, which will increase only the time required to adequately borate the RCS. Sufficient boric acid will still be available for RCS boration.

RCS inventory control is necessary in Modes 5 and 6 to ensure sufficient water is available for core cooling. A rapid loss of RCS inventory due to catastrophic pipe failures is unlikely in Mode 5 or 6 due to the reduced RCS pressure and temperature. An inventory loss is more likely to occur due to small system component failures or during infrequently performed evolutions. This type of inventory loss will occur at a slower rate. Plant operators will have time to

.- _- . - . . .- ._. -. -. . - - - - _ , . = . __ . .

U. G. Nuclear Regulatory Commission ,

B16809/ Attachment 1/Page 19 l perfomt the necessary actions to mitigste the event. Reliance on automatic l operation of the Emergency Core Cooling System is not necessary and .

I Technical Specifications do not require automatic actuation by the Engineered Safety Features Actuation System to be operable in Mode 4 or below. Operator ,

action is sufficient to mitigate a loss of RCS inventory in Mode 4 or below.

A loss of RCS inventory in Mode 5 or 6 is not an analyzed accident contained in l the Millstone Unit No. 2 FSAR. Therefore, in accordance with the criteria established in 10CFR50.36(c)(2)(ll), there is no need to establish requirements in Technical Specifications for RCS makeup capability b Modes 5 and 6. This position is supported by the new Standard Technical Specifications for Combustion Engineering plants (NUREG-1432). NUREG-1432 contains core cooling requirements in Modes 5 and 6, but does not establish any specific RCS makeup requirements. Plant procedures and shutdown risk management provide adequate controls to ensure sufficient RCS makeup capability is available.

The proposed change will only require one charging pump to be operable in Modes 5 and 6. A HPSI pump will no longer be required to be operable in Modes 5 and 6. However, plant procedures and shutdown risk management will require more than one RCS makeup source to be available. This defense in depth approach will ensuro sufficient RCS makeup capability is available and will allow plant operators to reploly take the actions necessary for RCS inventory control, i in addition, Technical Specifications will allow additional RCS makeup puri.ps to be capable of injecting into the RCS during reduced inventory operations. When the plant is operating in reduced inventory, the RCS will be vented. If the RCS vent is t 2.2 in' (removing the pressurizer manway, the normal vent path, will meet this requirement) an additional charging pump and one HPSI pump can be capable of injecting into the RCS, as specified in the proposed changes to Technical Specification 3.4.9.3. The availability of these additional pumps will ensure sufficient RCS makeup is available during reduced inventory operations.

Even though the propossd change will remove the Technical Specification requirement for an operable HPSI pump in Modes 5 and 6, sufficient RCS makeup capability will be available for RCS inventory and reactivity control.

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

2. The LTOP requirements currently contained in Technical Specifications 3.1.2.3 and 3.5.3 will be relocated to the LTOP Technical Specification 3.4.9.3.

Relocating requirements within Technical Specifications will not change any technical requirement. If a technical requirement is changed, it will be addressed separately in this submittal. Therefore, the proposed changes will havo no adverse effect on plant safety.

U. S. Nuclear Regulatory Commission B16809/ Attachment 1/Page 20

3. The RCS venting requirements currently contained in Technical Specification 3.4.9.3, and the RCS makeup requirements that will be relocated to Techaical Specification 3.4.9.3 need to be modified to be consistent with the new LTOP analysis performed.

The current LTOP mass input restrictions allow two charging pumps (Technical Specification 3.1.2.4) and one HPSI pump (Technical Specification 3.5.3) to be capable of injecting into the RCS when the RCS is operating in Mode 4 5 275 'F.

In Modes 5 and 6 only one charging pump and one HPSI pump (Technical Specification 3.1.2.3) are allowed to be capable of injecting into the RCS.

However, an additional charging pump and HPSI pump can be capable of injecting into the RCS if the RCS is vented through a passive vent P 2.8 in'.

The proposed changes to the mass input restrictions will still allow two charging pumps and one HPSI pump to be capable of injecting into the RCS when the RCS is operating in Mode 4 5 275 'F. This combination will be allowed in Mode 5 until RCS temperature is 5190 'F. When RCS cold leg temperature is at or below 190 'F only one charging pump will be allowed to be capablo of injecting into the RCS. This restriction will continue to apply until the RCS is vented through at least a 2.2 in' vent. If this venting restriction is met, two charging pumps and one HPSI pump will be allowed to be capable of injecting.

These proposed changes are all more restrictiv6 than the previous requ!rements, except for allowing two charging pumps and one HPSI in Mode 5 betw9en 200 *F and 190 'F. However, the proposed mass input restrictions are consistent with the new LTOP analysis. This analysis has demonstrated that with the proposed restrictions the required LTOP system will provide adequate protection to ensure thn RCS pressure does not exceed the Appendix G limits.

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

4. The applicability of Technical Specification 3.4.9.3 will be expanded to include all of Mode 5, and Mode 6 until the reactor vessel head is removed. The current applicability is limited in Modes 5 and 6 to when the RCS is not vented through a vent > 2.8 square inches. Expanding the applicability will ensure an LTOP System is in place except when RCS pressurization is not possible (reactor vessel head removed). This more restrictive change will have no adverse effect on plant safety.

5. The required PORV actuation setpoint will be reduced from 5 450 psig to 5 415 psia (400 psig). The 50 psi setpoint reduction (pressure units have also been changed to agree with control room indication) will cause the PORVs to actuate earlier during an LTOP transient to prevent RCS pressure from exceeding the Appendix G limits.

U. S. Nuclear Regulatory Commission s B16809/ Attachment 1/Page 21 The LTOP analysis performed included all anticipated LTOP performance diaracteristics such as PORV opening time delays resulting from valve stroke time delays and instrumentation process delay times. Other issues such as PORV inlet subcooling, and PORV discharge piping backpressure were also included in the analysis. The additional margins included in the analysis, resulted in lower allowable RCS pressures during the plant heatup and cooldown. As a result of this, the previous PORV setpoint of 450 psig (465 psla) ;

was not adequata to ensure that the allowable RCS pressure will not be exceeded during design basis LTOP events. This will require the PORV setpoints to be lowered to 415 psia (400 psig).

This is a more restrictive change that is consistent with the new LTOP analysic, it wili have no adverse effect on plant safety.

6. Changes to the action statemerits of Technical Specification 3.4.9.3 are necessary to be consistent with the proposed changes to the Limiting Condition For Operation (l.CO) which are based on the new LTOP analysis.

The passive vent required if one or two PORVs are inoperable (TSASs a, b, and c) will be changed from 2.8 in' or 1.4 in' to 2.2 in'. A passive vent of 1.4 in'is equivalent to the vent area of one PORV. Since the LTOP analysis assumes 2 operable PORVs initially, and then one PORV falls to actuate, RCS overpressure protection will be ensured by a passive vent of 1.4 in'. However, a passive vent is established by removing a pressurizer PORV or the pressurizer manway, the normal vent path. The value of 2.2 in' is the minimum size of vent that will ensure RCS pressure remains 5 300 psla, which is more conservative than the Apper. dix G limits. This vent size will also ensure that RCS pressure does not exceed the SDC System design pressure, in addition, this is the size of vent tha' will satisfy Technical Specification 3.4.9.1 to allow a 50 'F/hr cooldown rate below 190 *F. Therefore, the proposed changes will have no adverse effect on plant safety.

An action statement will be added to address excessive pumping capacity. The required completion time of 'immediate" reflects the importance of this restriction, and is consistent with current Technical Specification requirements (Technbal Specification 3.1.2.3 TSAS b and Technical Specification 3.5.3 TSAS c) for this situation. This proposed change will have no adverse effect on plant safety.

7. The RCP start criteria contained in Technical Specification 3.4.1.3 will be revised.

The requirements to start the first RCP, when RCS temperature is 5 275 'F, will be modified. The new criteria will ensure that starting an RCP will not result in an energy addition transient beyond the capability of the steam bubble in the

_ . _ ~ _ _ . __ _ - . _ .

l U. S. Nuclear Regulatory Commission B16809/ Attachment 1/Page 22 pressurizer to mitigate. This will ensure that the 10CFR50 Appendix G limits are I

not exceeded.

l When any RCS cold leg temperature is 5 275 'F, it will be necessary to ensure a steam bubble of sufficient size in the pressurizer, ensure RCS pressure is consistent with the analysis assumptions, and minimize the delta-T between the RCS and the secondary system. If these limitations are met, the energy addition .

from starting an RCP will not result in an excessive RCS pressure increase. l These limitations are not necessary if at least one RCP is already operating.

With at least one RCP operating, RCS flow will be sufficient to ensure that the primary and secondary side of each steam generator are at essentially the same temperature.

These restrictions are consistent with the new LTOP analysis, although no credit hP.s been taken for PORV actuation during the energy addition transient. This analysis has demonstrated that with the proposed restrictions the required steam volume in the pressurizer will provide adequate protection to ensure RCS pressure ooes not ex% sd the Appendix G limits. Therefore, the proposed changes will have no adverse effect on plant safety.

8. A footnote will be added to Technical Specification 3.5.3 to allow entry into Mode 4 without an operable HPSI pump.

This new footnote will allow the plant to enter Mode 4 where Technical Specification 3.5.3 is applicable without any operable HPSI pumps. However, this condition will only be allowed for a very chort time period, one hour. The proposed change to Technical Specification 3.4.9.3 will allow a HPSI pump to be operable above 100 'F. However, the 10 *F range before Mode 4 is reached may not allow sufficient time to ensure a HPSI pump is operable. Adding this note will provide the operating crew sufficient time to make an orderly transition into Mode 4. This condition will only be allowed for one hour, which is the same time allowed by the first part of TSAS a for an inoperable HPSI pump.

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

9. The reference contained in the first footnote (*) to Technical Specification 3.1.2.4 will be changed from 3.1.2.3 to 3.4.9.3 to reflect where the LTOP requirements will be located. This is an administrative change that will have no adverse effect on plant safety.

Boron Dilution Changes The analysis of the boroa dilution svent contained in the Millstone Unit No. 2 FSAR Section 14.4.6 assumes that dilution flow rate is limited to 88 gpm in Modes 4,5, and 6. Since the charging pumps are the assumed dilution source, no more than two charging pumps can be injecting for this assumption to remain

U. S. Nuclear Regulatory Commission B16809/ Attachment 1/Page 23 valid. This results in a Technical Specification requirement that no more than two charging pumps can be operable when the RCS is in Mode 4 or below (<

300 'F). This requirement will be modified by replacing the word " operable' with

" capable of injecting into the RCS.' This more accurately addresses the boron dilution analysis restriction of limiting the dilution flow to two charging pumps since an inoperable pump can still inject into the RCS. This change is consistent with the boron dilution accident analysis. The boron dilution analysis further assumes that if this dilution flow rate restriction is mot, there will be sufficient time for the operators to recognize and terminate the dilution before a complete loss of shutdown margin occurs. Operator action to restore shutdown margin by boration is not assumed.

The proposed changes will not affect the current Technical Specification restriction that no rnore than two charging pumps can be capable of injecting into the RCS (operable) when the RCS is below 300 'F. However, no corresponding action statament currently exists in TechHeal Specification 3.1.2.4 to provide guidance if this requirement is not met. the addition of the proposed action statement to Technical Specification 3.1.2.4 will require immediate action to l co rect this situation. This is consistent with other current Technical l Specification requirements (Technical Specification 3.1.2.3 TSAS b and l Technical Specification 3.5.3 TSAS c) that address excessive RCS makeup l capacity. Therefore, the addition of this action statement, a more restrictive change, will have no adverse effect on plant safety.

RCS Heatup and Cooldown Changes l 1. A new analysis has been performed to develop new RCS pressure / temperature l curves and hcatup and cooldown limits. The heatup and cooldown rates will be i increased to provide flexibility during plant heatup and cooldown, and especially during equipment manipulations such as securing RCPs, swapping SDC heat l exchangers, and initiating SDC. This need was identified during the review of the 1995 and 1996 heatup/cooldown events which resulted in violation of the l

I current Technical Specification requirements.

l l The ncw analysis includes additional allowances not contained in the current

analysis. These additional allowances include the following items.

1

a. The instrument uncertainties previously used in the development of the Millstone Unit No. 2 heatup and cooldown curves did not include the overall system uncertainties during the various operating conditions, i analyzed. These additional considerations have resulted in an increase in the uncertainty associated with monitoring RCS pressure and temperature.

U. S. Nuclear Regulatory Commission B16809/ Attachment 1/Page 24 ,

b. The current pressure / temperature limits provided in Technical Specifications do not include all appropriate pressure adjustments between the location of the pressure instrumentation and the limiting vessel beltline region. These additional adjustments will account for such issues as elevation differences, pressure drop across the core due to the operation of RCPs, and other hydraulic losses. This will result in additional RCP starting and operating restrictions to ensure that the pressure at the vessel beltline region does not exceed the 10CFR50 Appendix G limits,

c. Reviews of the original vessel fabrication documentation performed in response to Generic Letter (GL) 92-01 requirements, identified additional copper (Cu) and nickel (NI) content v' alues which had not been previously considered in establishing the chemistry factor as required by Regulatory Guide 1.99, Revision 2. This additional data has been included in the calculations performed to develop the proposed heatup and cooldown curves.

Figure 3.4.2 will be replaced by two curves, Figures 3.4-2a and 3.4-2b. The temperature change limits will be located in the new Table 3.4 2, instead of in the LCO. The new limits will use cold leg temperature instead of average temperature to determine when to change rates. There should be little difference between these two temperatures, and cold leg indication is directly available to the control room operators.

The proposed curves and rates are based on indicated cold leg temperature.

This parameter, which is the best available indication of reactor vessel downcomer temperature, will normally be monitored by using either RCS cold leg temperature indication or SDC return temperature. Plant conditions will determine which one is the appropriate indication to use. Actual RCS cold leg temperature will be used if any RCP is operating or natural circulation is occurring. Otherwise, SDC return temperature will be used.

Figure 3.4-2a will address plant heatup. The heatup limits, which will be contained in Table 3.4-2, have been changed as a result of the new analysis.

The minimum reactor vessel bolt-up temperature, the minimum temperature for criticality, and the hydrostatic and leak test limit will be located on Figure 3.4 2a.

RCP restrictions, assumed in the development of the heatup curves, will be added. The RCP restriction of only two RCPs below 200 'F is already covered by Technical Specification 3.4.1.4. The RCP restriction of four RCPs above 500

'F is a new Technical Specification requirement. However, since plant procedures already contain this restriction, there will be no effect on plant operations.

.- r. - . . - - , , - . . - . . ,n. -- - - , - - , - - , , . . ,

U. 8. Nuclear Regulatory Commission 816809/ Attachment 1/Page 25 Figure 3.4 2b will address plant cooldown. The cooldown limits, whidi will be contained in Table 3.4 2, have been changed as a result of the new analysis.

Two cooldown curves will be available when RCS temperature is below 230 *F,-

The minimum reactor vessel bolt-up temperature will be located on Figure 3.4-2b. RCP restrictions, assumed in the development cf the cooldown curves, will be added. The RCP resirletion of three RCPs between 200 *F and 500 *F is a !

new Technical Specification requirement. However, plant procedures already j specify that the plant must be above 500 'F before four RCPs can be operated. l Also, since plant procedures already specify securing two _RCPs when the cooldown is initisted, there will be no effect on plant opt, rations due to this new restriction. The RCP restriction of only two RCPs below 200 'F is already :

oovered by Technical Specification 3.4.1.4. The restriction of no RCP operation ;

below 150 'F during a plant cooldown is a new restriction. However, since all RCPs would normally be secured by this point in the cooldown, there will be no ;

effect on plant operations due to this new restriction. l The 50 'F/hr cooldown rate and curve will normaHy he used when the RCS is 5 !

190.*F and an RCS vent of > 2.2 in' has been established. This curyw and rate j may also be used when RCS cold leg temperature is below 230 *F to demonstrate compilence with Appendix G limits when unanticipated temperature excursions occur. The use of these special limits is covered in more detail in the addition to the Bases of Technical Specification 3.4.9.1. i in some cases the proposed pressure! temperature curves require a lower RCS pressure for a given RCS temperature, and the proposed heatup and cooldown ,

temperature change rates allow a higher rate than currently allowed. However, i the new curves and rates have been calculated using standard approved methods that ensur9 the margins of safety required by 10CFR50, Appendix G are maintained. Therefore, the proposed chsoges will have no adverse effect on plant safety. ;

2. The applicability of Technical Specification 3.4.9.1 will be increased, i The current applicability is Modes 1 through 5. However, concern for non-ductile failure of the reactor vessel and flange applies et all times, not just in Modes 1 through 5. Therefore, the applicability will be expanded. Increasing the applicability of Technical Specification 3.4.9.1 will place additional restrictions

on the plant. However, these additional restrictions will ensure the integrity of the RCS, in particular the reactor pressure vessel, is maintained. Therefore, the ;

- RCS will centinue to function as designed. This proposed change will have no adverse effect on plant safety._ ,

t a

m,-r e- n--sr w- r..-- ~=.,~,% wn.e.--:,m,us.* ws,.-.om-.- %, ..v-,,e ,. -,.--ww.,,.-------.-,--, s w :-e. 4.#.m.mm,,w%-.-%,v.-w.- . - - -

= -_ . _ _ . . -- . . . -. - -

U. S. Nuclear Regulatory Commission B16809/ Attachment 1/Page 26

3. The inservice leak and hydrostatic testing requirement will be modifivt and ,

clarified. ;

The inservice leak and hydrostatic testing temperature change limit currently specified in Technical Specification 3.4.9.1.c will be relocated to Table 3.4 2.

The wording will be modified (cla.-ification only) to specify the limit also applies ,

for one hour prior to the start of inservice leak and hydrostatic testing. This is necessary since the development of the inservice leak and hydrostatic testing test curve assuny s isothermal conditions. The wording will also be modified to specify the restrictions apply during testing above the heatup curve instead of above system design pressure. This type of test!ng is not performed above system design pressure. This proposed change will have no adverse effect on plant safety.

4. The current TSASs of Technical Specification 3.4.9.1 will be separated by Mode and will be modifici Similar changes will be made to the action statements of Technical Specification 3.4.9.2.

a. In Modes 1 through 4, the 30 minute time period for limit restoration will remain the same. A time limit of 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months will be placed on the performance of the engineering evaluation. If this evaluation is not performed in this time period, or the evaluation does not allow continued operation, the plant will be required to enter Mode 5 ($ 200 *F), instead of the current requirement to be < 200 'F. This slight relaxation will have no significant impact on plant operations because plant temperature is not normally maintained at the mode change temperature limit. Also, defining plant condition by mode, instead of by pressure and temporature, is consistent with the action requirements of most Technical Specifications.

l

b. The required RCS pressure will be reduced from 500 psia to 300 psia.

This change will require plant conditions that are closer to the actual plant

, conditions established in Mode 5. Operation of the SDC System l

(administrative limit on RCS pressure of 265 psla) and the proposed l LTOP System (PORV setpoints s 415 psla) require RCS pressure to be below the current 500 psia limit. Also, establishing a lower RCS pressure is more conservative because it will result in lots pressure stress on the reactor vessel,

c. In other than Modes 1 through 4, immediate action will be required for limit restoration. Violation of these limits is typically more severe when L the RCS is cold (< 200 'F), therefore an immediate response is i appropriate. A time limit of prior to entering Mode 4 will be placed on the performance of the engineering evaluation. This will prevent plant startup until. the evaluation has determined that the RCS is acceptable for continued operation.

U. S. Nuclear Regulatory Commission B16809/A tachment 1/Page 27

d. The current action requirements for the Pressurizer, Techn; cal Specification 3.4.9.2, will be modified to be consistent with the proposed changes to Technical Specification 3.4.9.1. The wording of the purpose ,

of the engineering evaluation will be changed from

fracture toughness properties of the pressurizer" to ' structural integrity of the pressurizer.'

This proposed wording correctly describes the purpose of the engineering evaluation and is consistent with Technical Specification 3.4.9.1. A time limit of 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months will be placed on the performance of the engineering evaluation, if the evaluation is not performed in this time period, or the evaluation does not allow continued operation, the plant will be required to enter Mode 3 within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and reduce pressure to below 500 psia within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months . The required RCS pressure will be reduced from 500 psig to 500 psia. This change in pressure units is consistent with t plant instrumentation and other Technical Specifications. Also, establishing a lower pressure is more contarvative because it will result in less pressure stress on the pressurizer.

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

5. The frequency of Surveillance Requirements (SRs) 4.4.9.1.a, 4.4.9.2, 4.10.3.1 will be increased from once per hour to once per 30 minutes. This more restrictive change will provide the plant operators with earlier indication that a limit may be exceeded, so that action can be taken to prevent exceeding the limit. These proposed changes will have no adverse effect on plant safety.

6. Technical Specification 3.10.3 and SR 4.4.9.1.b (currently SR 4,4.9.1.c) will be revised to reference the new curves that will be added to Technical Specification 3.4.9.3. This is an admirJstrative change that will have no adverse effect on plant safety.

Other Changes

1. Various redundant or outdated Technical Specification requirements will be eliminated.

a. SR 4.1.2.2.c will be modified to remove the "" and associated footnote.

The time period covered by this footnote has passed. Therefore, this footnote can't be used and should be removed.

b. Technical Specifications 3.1.2.3 and 3.1.2.5 will be modified to remov:,

the requirement for the required operable pump to be powered frva an operable emergency bus. This is redundant wording to the definition of operable and can be removed without affecting any operability requirements. The LCOs will be modified, SRs 4.1.2.3.1.c and 4.1.2.5.d

U. 8. Nuclear Regulatory Commission 816809/ Attachment 1/Page 28 will be deleted, and SRs 4.1.2.3.1.a, 4.1.2.3.1.b, 4.1.2.5.b and SR 4.1.2.5.c will be modified (editorial changes only) accordingly.

c. SR 4.4.9.1.b will be deleted. SR 4.4.9.1.b is redundant to SR 4.1.1.5 of Technical Specification 3.1.1.5, ' Minimum Temperature For Criticality' This redundancy is not necessary to ensure compliance with the limit. SR 4.4.9.1.c will be modified accordingly.

Removal of redundant or outdated requirements from Technical Specifications will not impact any technical requirements. These are administrative changes only that will have no adverse effect on plant safety.

2. The scope of the action statement for Technical Specification 3.1.2.6 will be expanded to cover all three flowpaths identified in Technical Specification 3.1.2.2.a. The current wording does not cover the flowpath identified in 3.1.2.2 a.2. The procosed changes, replacing the word *one' with *the" and adding *(s)" to " pump

will allow the action statement to apply to this flowpath.

The intent of the current wording is to address all flowpaths. These minor wording changes meet this intent. These proposed changes will have no adverse effect on plant safety.

3. Guidance on survelliance performance will be added to SR 4.1.2.8.d. SR 4.1.2.8.d will be modified to allow the boric acid storage tank (BAST) temperature to be verified by checking the ambient air temperature. This is currently allowed by SR 4.1.2.7.c. This proposed change will have no adverse effect on plant safety. ,

4. A note will be added to Technical Specification 3.4.3 to allow the block valve (s) to be cycled during plant coo ldown when in TSAS a. This action statement

+ plies when the PORVs are inoperable, but capaole of being manually cycled.

The footnote will allow the PORV block valve (s) to be cycled during a plant cooldown to prevent thermal binding. This will ensure the PORV(s) which is(are) inoperable, can be maneally cycled if necessary. This proposed change will minim,ze the potential inability to open the PORV block valve (s) due to thermal binding. Theiefore, the PORV block valve (s) will be able to function as designed. This proposed change will have no adverse effect on plant safety.

5. The wording of Technical Specification 3.4.3, Action Statement d, will be revised to state %at action should be performed, and to remove specific details on how to perform the required action. The Bases for this specification will be expanded to include a discussion of pssible methods to accomplish the required action, in addition, the current wording is not correct because there is no 'close" position associated with tlie main control board PORV control switches. The technical requirements of this action statement will remain the same and the terminology used will agree with plant equipment. This does not ciiange the e- r*. -e , -,v +=4 e --++e-- Tv am-4>r- s--e---+ee emw--+ yr- t- _-- ali P4- t- 4-w - p- :r-e*='w'Niv

U. S. Nuclear Regulatory Commission B16809/ Attachment 1/Page 29 i I

intent of the action statement. This proposed change will have no adverse effect on plant safety.

6. An action statement will be added to Technical Specification 3.4.9.3. The proposed action statement will provide an exception to Technical Specification 3.0.4. .

Adding a new action statement which states the provisions ci Technical Specification 3.0.4 are not applicable, is necessary 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(a), i This change is consistent with the old Standard Technical Specifications for ,.

Combustion Engineering plants (NUREG0212). The new Standard Technical Specifications for :ombustion Engineerire plants (NUREG-1432) does not include this provisim for the appropriate LTOP specification (3.4.12). The wording of Specificatbn 3.0.4 in NUREG-1432 states "or other specified condition in the Applicability for an unlimited period of time.' Therefore, it is not r'ecessary for NUREG 1432 to include this exemption. This proposed change l

will have no adverse effect on plant safety.

\

l 7. Minor wording changes have been made to many of the Technical Specifications contalried .5n this License Amendment Request. These changes do not change -

any technical aspect of the respective Technical Specifications. They are I editorial changes only. Therefore, the proposed changes will have no adverse i

effect on plant safety.

! 8. The Bases of Technical Specifications have been modified and expanded to

! address these proposed changes and to correct items identified during the I

revie / of the Bases. The information added will provide background information concerning the analyses performed, and provide guidance on operating the plant in accordance with the Technical Specification requirements. These proposed changes will have no adverse effect on plant safety.

The proposed changes have no significant effect on how any of the associated systems j or components function to prevent or mitigate the consequences of design basis l

accidents. Also, the proposed changes have no significant effect on any design basis accident previously evaluated. Therefore, there is no significant impact on public health and safety.

I l

1

k I

r Docket No. D336 i S.1BBQE ,

. l I

i i

Attachment 2 i Millstone Nuclear Power Str. tion, Unit No. 2 l Proposed Revision to Technical Specifications Reactor Coolant System Heatup/Cooldown Limits and Low Temperature Overpressure Protection ,

Significant Hazards Consideration i

I i

e 4-a k

November 1997 l

U. S. Nuclear Regulatory Commission l B16809/ Attachment 2/Page 1 Proposed Revision to Technical Specifications i Reactor Coolant System Heatup/Cooldown Limits 1 and Low Temperature Overpressure Protection Significant Hazards Consideration .

Sionificant Hazards Consideration ;

in accordance with 10CFR50.92, NNECO 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. The proposed changes do not involve an SHC because the changes would not:

1. Involve a significant increase in the probability or consequences of an accident previously evaluated.

Each of the proposed changes have been grouped together, as appropriate, to address this criteria.

HPSI Pumo Not Reauired To Be Operable in Modes 5 and 6 The proposed change to only require one charging pump to be operable in Modes 5 and 6. Instead of the current requirsment for one charging pump and one high pressure safety injection pump (HPSij pump to be operable, will result in sufficient, but not ecessive, Reactor Coolant System (RCS) makeup capability. When the plant is in Modo 5 or 6 there are two major factors to consider with respect to the number of RCS makeup pumps required to be _

operable, if too many RCS makeup pumps are iaquired, an inadvertent start of these pumps can result in a mass addition transient beyond the capacity of the Low Temperature Overpressure Protection (LTOP) System. This may result in an RCS pressure increase that exceeds the 10CFR50 Appondix G pressure / temperature limits. Compliance with the mass input and venting restrictions contained in the proposed Technical Specification 3.4 9.3 will ensure the Appendix G limits are, not exceeded.

The minimum number of RCS makeup pumps required to be operable in Modes 5 and 6 ensures sufficient makeup capability b available for RCG inventory control and RCS boration requirements. RCS inventory control is necessary in Modes 5 and 6 to ensure sufficient water is available for core cooling. A rapid loss of RCS inventory due to catastrophic pipe failures is unlikely in Modes 5 and 6 due to the reduced RCS pressure and temperature. An inventory loss is more likely to occur due to small system component failures or dering infrequently p.,rformed evolutions, such as reduced inventory operation. This type of inventory loss will occur at a slower rate. Plant operators will have time to perform the necessary actions to mitigate the event. Reliance on automatic

U. S. Nuclear Regulatory Commission l B16809/ Attachment 2/Page 2 !

operation of the Emergency Core Cooling System is not necessary and Technical Specifications do not require automatic actuation by the Engineered Safety Features Actuation System to be operable in Mode 4 or below. Operator action is sufficient to mitigate a loss of RCS inventory in Mode 4 or below, i provided sufficient RCS makeup capability is available. Plant procedures and shutdown risk management will provide adequate administrative control to ensure sufficient RCS makeup capability is available, or that contingency plans have been developed. )

1 The minimum number of RCS makeup pumps required to be operable in Modes !

5 and 6 ensures sufficient makeup capability is available for RCS borabon i requirements. The RCS is required to be borated to a sufficient boron !

concentration to ensure the Technical Specification Shutdown Margin (SDM) l requirements are met. The appropriate SDM requiremento must be met before i entry is allowed into Mode 5 or 6. RCS boron concentration is increased to establ'sh the required SDM. This is normally accomplished by P1 Jing borated water to the RCS during plant cooldown to compensate for the e sntraction of the ,

RCS inventory. The proposed change will restrict the nt.mber of pumps ]

available, which will increase the time required to adequately borate the RCS.

However, the enange will not affect the ability to add boric acid to the RCS.

Even though the proposed change will remove the Technical Specification i requirement for an operable HPSI pump in Modes 5 and 6, sufficient RCS makeup capability will be available to meet RCS boration and inventory requirements. Therefore, the proposed change will not result in a significant increase in the probability or consequences of an accident previously evaluated.

LTOP Mass Inout and Vent Size Reaulrements The proposed changes to the RCS venting requirements currently contained in Technical Specification 3.4.9.3, and the RCS makeup requirements that will be relocated to Technical Specification 3.4.9.3 are necessary to be consistent with the new LTOP analysis. These changos will ensure the 10CFR50 Appendix G limits are not exceeded.

The proposed change to the mass input restrictions wili still allow two charging pumps and one HPSI pump to te capable of injecting into the RCS when the RCS is operating in Mode 4 5 275 'F. This combination will be allowed in Mode 5 until RCS temperature is 5190 'F. When RCS cold leg temparature is at or below 190 'F only one charging pump will be allowed to be capable of injecting into the RCS. This restriction will continue to apply until the RCS is vented through a passive vent > 2.2 in'. If this passive vent size is established, two charging pumps and one HPSI pump are allowed to be capable of injecting.

U. S. Nuclear Regulatory Commission B16809/ Attachment 2/Page 3 The passive vent mquired if one or two power operated relief valves (PORVs) are Inoperable (Technical Specification Action Statements (TSASs) a, b, and c) will be changed from 2.8 in or 1.4 in' to 2.2 in'. A passive vent of 1.4 in'is i equivalent to the vent area of one PORV. Since the LTOP analysis assumes 2 operable PORVs inilla!!y, and then one PORV falls to actuate, RCS overpressure protection will be ensured by a p" assive vent of 1.4 in'. However, a passive vent is established by removing a pressurizer PORV or the pressurizer manway, the normal vent path. The value of 2.2 in' is the minimum size of vent that will ensure RCS pressure remains 5 300 psia, which is more conservative than the Appendix G limits. This vent size will also ensure that RCS pressure does not exceed the SDC Si r'em design pressure. In addition, this is the size of vont that w!!! satisfy Technical Specification 3.4.9.1 to allow a 50 'F/hr cooldown rate below 190 'F.

TSAS d will be added tc, address excessive pumping capacity. The required completion time of "irt.nu.diate" reflects the importance of this restriction, and is consistent with current Technical Specification requirements (Technical Specification 3.1.2.3 TSAS b and Tochnical Specification 3.5.3 TSAS c) for this situation.

These proposed changes are all more restrictive than the previous requirements, except for allowing 2 charghg pumps and one HPSI in Mode 5 between 200 'F and 190 'F, and requiring a vent of 2.2 in'instead of 2.8 in' when two PORVs are inoperable. However, the proposed mac input and venting restrictions are consistent with the new LTOP analysis. This analysis has demonstrated that with the proposed restrictions the required LTOP system will provide adequate protection for RCS overpressurization transients.

Therefore, the proposed changes will not result in a significant increase in the l probability or consequences of an accident praviously evaluated.

Increase in Technical Specification Applicability l Tbc applicability of Technical Specification 3.4.9.3 will be expanded to include l all of Mode 5, and Mode 6 until the reactor vessel head is removed. The current l applicability is limited in Modes 5 and 6 to when the RCS is not vented through a vent 12.8 in'. Expanding tne vpplicability will ensure an LTOP Syctem is in place, except when RCS pressurization is not possible (reactor vessel head

! removed). This will ensure the 10CFR50 Appendix G limits are not exceeded.

l l The applicability of Technical Specification 3.4.9.1 will be expanded. The current applicability is Modes 1 through 5. However, concern for non-ductile failure of the reactor vessel and flange applies at all times, not just in Modes 1 through 5. Therefore, the applicability will be expanded. Increasing the applicability of Technical Specification 3.4.9.1 will place adc'itional restrictions on the plant. However, these additional restrictions will ensure the integrity of

U. S. Nuclear Regulatory Commission B16809/ Attachment 2/Page 4 the RCS, in particular the reactor pressure vessel, is maintained. Therefore, the RCS will continue to function as designed.

These more restrictive changes will not result in a significant increase in the probability or consequences of an accident previously evaluated.

LTOP PORV Setooint.Chanae The required PORV actuation setpoint will be reduced from 5 450 psig to 5 415 psia (400 psig). The 50 psi setpoint reduction (pressure units have also been changed to agree with control room indication) will cause the PORVs to actuate earlier during an LTOP transient to preve.it an RCS overpressurizatiore. It is a more restrictive change that is consistent with the new LTOP analysis.

PORV actuation at the proposed setpoint, in combination with the proposed mass input restrictions, will ensure the 10CFR50 Appendix G limits are not exceeded. Therefore, the proposed change will not result in a significant increase in the probability or consequener of an accident previously evaluated.

RCP Start Criteria The requirements to start the first reactor coolant pump (RCP), when RCS temperature is 5 275 *F, will be modified. The new criteria will ensure that starting an RCP will not result in an energy addition transient that could exceed the capability of the steam bubble in the pressurizer to mitigate the event. (No credit for PORV actuation during this energy addition transient was assumed in l the new LTOP analysis.) This will ensure that the 10CFR50 Append.x G limits I are not 6xceeded.

The proposed RCP restrictions are consistent with the new LTOP analysis. This analysis has demonstrated that with the proposed restrictions the pressurizer will provide adequate protection for RCS overpressurization transients. Therefore, the proposed changes will not result in a significant increase in the probability or consequences of an accident previously evaluated.

Boron Dilution Analysic

The analysis of the boron dilution event contained in the Millstone Unit No. 2

! FSAR Section 14.4.6 assumes that dilution flow rate is limited to 88 gpm in l Modes 4,5, and G. Since the charging pumps are the assumed dilution sourca, no more than two charging pumps can be injecting for this assumption to remain l

valid. This results in a Technical Specification requirement that no more than two charging pumps can be operable when the RCS is in Mode 4 or below (<

300 'F). This requirement will be modified by replacing the word " operable" with

' capable of injecting into the RCS." This more accurately addresses the boron

U. S. Nuclear Regulatory Commission B16809/ Attachment 2/Page 5 dilution analysis restriction of limiting the dilution flow to two charging pumps since an inoperable pump can still inject into the RCS. This change is consistent with the boron dilution accident analysis. The boron dilution analysis fudher assumes that if this dilution flow rate restriction is met, there will be sufficient time for the operators to recognize and terminate the dilution before a complete loss of shutdown margin occurs. Operator action to restore shutdown margin by boration is not assumed.

The proposed changes will not affect the current Technical Specification restriction that no more than two charging pumps can be capable of injecting into the RCS (operable) when the RCS is below 300 'F. However, no corresponding action statement currently exists in Technical Specification 3.1.2.4 to provide guidance if this requirement is d aat. The addition of the proposed action statoment to Technical Specification 3.1.2.4 will require immediate action to correct this situation. This is consistent with other current Technical Specification requirements (Technical Specification 3.1.2.3 TSAS b and Technical Specification 3.5.3 TSAS c) that address excessive RCS makeup capacity. Therefore, the proposed changes will not result in a significant increase in the probability or consequences of an accident previously evaluated. .

RCS Pressure / Temperature and Heatup/Cooldown Limn Chanoes The proposed changes to the heatup and cooldown rates are a result of the new analysis of the RCS pressure / temperature and heatup/cooldown limits. These changes will provide flex;oility during plant heatup and cooldown, and especially during equipment manipulations such as securing RCPs, swapping shutdown cooling (SDC) heat exchangers, and initiating SDC.

Figure 3.4.2 will be replaced by two curves, Figures 3.4-2a and 3.4-2b. Each figure will contain the minimum flange boltup temperature and the minimum temperature for criticality. The heatup figure (Figure 3.4 2a) will also contain the inservice leak and hydrostatic testing limits. The temperature change limits will be contained in the new Table 3.4-2, instead of in the LCO. The new limits will use cold leg temo- ature instead of average temperatuia to determine when to change rates. There should be little difference between these two temperatures, and cold leg indication is directly available to the control room operators.

The propsed curvss and rates are based on indicated cold leg temperature.

This parameter, which is the best available indication of reactor vessel downcomer temperature, will normally be monitored by using either RCS cold leg temperature indicatien or SDC return temperature. Plant conditions will determine which one is the appropriate indication to use. Actual RCS cold leg temperature will be used if any RCP is operating or natural circulation is occurring. Otherwise, SDC return temperature will be used.

I l

U. S. Nuctoar Ragulatory Commission -

^

B16809/ Attachment 2/Page 6 RCP restrictions, assumed in toe development of the heatup and cooldown curves, will be added to the curves. Most of the RCP restrictions already exist either in other Technical Specifications or in plant procedures. Two new RCP restrictions will be added to Technical Specifications. The restriction of no more than three RCPs until RCS temperature is above 500 *F already exists in plant procedures, but it will be added to Technical Specifications. The restriction of no more than two RCPs when RCS temperature is b<.x w 200 *F already exists in Technical Specifications (3.4.1.4). The RCP restriuon of no RCPs below 150

F during plant cooldown will be added to Technical Specifications. This restric'M will have no effect on plant operations because RCPs will normally be secured when cooling down below 150 *F to r@lmize heat input.

The inservice leak and hydrostatic testing temperature change limit currently specified in Technical Specification 3.4.9.1.c will be relocated to Table 3.4-2.

The wording will be modified (clarification only) to specify the limit also applies for one hour prior to the start of inservice leak and hydrostatic testing. Thh, .s necessary sir'ce the development of the inservice leak and hydrostatic testing test curve assumes isothermal conditions. The wording will also be modified to specify the restrictions apply during testing above the heatup curve instead of above system design pressure. This type of testing is not performed above system design pressure.

The 50 *F/hr cooldown rate and curve will normally be used when the RCS is <

190 *F and an RCS vent of > 2.2 in' has been established. This curve and rate may also be used when RCS cold leg temperature is below 230 *F to demonstrate compliance with Appendix G limits when unanticipated temperature excurslow occur.

The current action statements of Technical Specification 3.4.9.1 will be separated by Mode and will be modified. Similar changes will be made to the aMinutatements of Technical Specification 3.4.9.2. A time limit of 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months will a p!ec ad on the performance of the engineering evaluation. if this evaluation is re.A bl .sfonted in this Eme period, or the evaluation does not allow continued operation, the plant will be required to enter Mode 5 (< 200 F), instead of the current requirement to oe < 200 F. This slight relaxation will have no significant impact on plant operations because plant temperature is not normally maintained at the mode change temperature limit.

The equired RCS pressure will be reduced from 500 psia to 300 psia. This is clot ar to the actual plant conditions established in Mode 5. The required RCS pressure will be reduced from 500 psig to 500 psia for the Pressurizer, Technical Specification 3.4.9.2. The change in units is consistent with plant instrumentation. Establishing a lower RCS pressure is more conservative because it will result in less pressure stress on either the reactor vessel or the pressurizer.

U. S. Nuclear Regulatory Commission B16809/ Attachment 2/Page 7 in other than Modes 1 through 4, immediate action will be required for limit restoration. Violation of these limlis is typically more severe when the RCS is cold (< 200 *F), therefore an immediate 'espc ose is appropriate. A time limit of prior to entering Mode 4 will be place I on th? performance of the engineering evaluation. This will prevent plant sta fup ur.il tre evaluation has determined that the RCS is acceptable for continued owration.

The frequency of surveillance requirements 4.4.9.1.c, 4.4.9.2, 4.10.3.1 will be increased from once per hour to once per 30 minutes. This more restrictive change will provide the plant operators with earlier indication that a lirait may be exceeded, so that action can be taken to prevent exceeding the limit.

The proposed changes to the RCS pressure / temperature limits and temperature change rates are based on the new analysis. This analysis uses standard approved methods that ensure the margins of safety required by 10CFR50, 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.

U Other Chanaes The scope of the action statement for Technical Specification 3.1.2.6 will be expanded to cover all three flowpaths identified in Technical Specification

.; 3.1.2.2.a. The intent of the current wording is to address all flowpaths. These minor wording changes will meet this inter.t.

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^

Clarification will be added to SR 4.1.2.8.d to be consistent with SR 4.1.2.7.c.

The clarification will allow the boric acid storage tank (BAST) temperature to be verified by checking the ambient air temperature.

A note will be added to Technical Specification 3.4.3 TSAS a to allow the block valve (s) to be cycled during plant cooldown when the block valve (s) is(are) closed due to inoperable PORV(s). 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 opened to allow the PORV(s) which is(are) inoperable, can be manually cycled if necessary. Therefore, the PORV block valve (s) will be able to function as designed.

The wording of Technical Specification 3.4.3 Action Statement 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 intent of the action statement. Therefore, the pressurizer PORVs will continue to function as designed.

U. S. Nuclear Reguictory Commission B16809/ Attachment 2/Page 8 An action statement will be added to Technical Specification 3.4.9.3 to provide an exception to Technical Specification 3.0.4 requirements. This is necessary to allow a plant noldown to MODE 5 K one or both PORVs are inoperable. MODE 5 cor&ditions may be necessary to repair the PORV(s).

A footnote will be added to Technical Specification 3.5.3 to allow entry into Mode 4 without an operable high pressure safety injection pump. This new footnote 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 period, one hour. The proposed change to Technical Specification 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 a HPSI pump is operable. Adding this note will provide the operating crew sufficient time to make an orderly transition into Mode 4. This condition will only be allowed for one hour, which is the same time allowed by the first part of TCAS a for an inoperable HPSI pump.

The LTOP requirements currently contained in Technical Specifications 3.1.2.3 and 3.5.3 will be relocated to the LTOP Technical Specification 3.4.9.3.

Relocating requirements within Technical Specifications will not change the technical content of the requirement.

Various redundant or outdated Technical Specification requirements will be eliminated and references will be adjusted to reflect the proposed changes.

Removal of redundant or outdated requirements from Technical Specifications and adjustments to references to other requirements will not impact any technical requirements.

Minor wording changes have been made to many of the Technical Specifications contained in this license amendment request. These changes do not change any technical aspect of the Technical Specification affected. They are editorial changes only.

The proposed changes do not alter the way any structure, system, or component functions. There will be no effect on equipment important to safety. Therefore, the proposed changes will not result in a significant increase in the probability or consequences of an accident previously evaluated The proposed changes have no effect on any of the design basis accidents previously evaluated. Therefore, the license amendment request does not impact the probability of an accident previously evaluated nor does it involve a significant increase in the consequences of an accident previously evaluated.

4 = . :J ;

_U. S. Nuclear Regulatory Commission :

B16809/ Attachment 2/Page g- l

' 2. Create the possibility of a new or different kind _of accident from any accident previously evaluated.- a The proposed changes will not alter the plant configuration (no new or different k 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. Involve a significant reduction in a margin of safety.

?The: proposed changes ' will- modify- the LTOP requirements, RCS pressure / temperature limb, and the RCS heatup and.cooldown limits. The majority _ of the proposed changes are being-made as a result of the new

. pressure / temperature and -LTOP analyses performed. The new pressure / temperature curves and heatup and cooldown rates were developed in L

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 new LTOP mass input and RCP starting restrictions and LTOP_ PORV setpoints are consistent with the criteria contained in the Standard y Review Plan Section 5.2.2. Additional changes have been proposed to correct I various items identified during the review cithe Millstone Unit No. 2 Technical SpeciMeations. The proposed changes do_ not change the requirements to maintain RCS pressure and temperature within the requirements defined in j[ Technical Specifications. This will ensure the integrity of the reactor vessel is J maintained during all aspects of plant _ operation. Therefore, there is no L significant effect on the probability or consequences of any accident previously l

evaluated and no significant impact on offsite doses associated with previously '

l 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.

The- NRC has provided guidance concerning the application of standards in 10CFR50.92. by providing certain examples (March 6, 1986, 51 FR 7751) of i amendments that a_re considered not likely to involve an SHC. The changes proposed herein to correct terminology, numberingc. references, and. relocating requirements

- within Technical _ Specifications are enveloped by example (i), a purely administrative change so Technical Specifications The more restrictive changes poposed herein that

are based on the new analyses performed and the more restrictive enhancements are .

enveloped by example-(ii), a change that constitutes an additional limitation, restriction,

- or_ control not presently included in Technical Specifications. All other changes proposed herein are not enveloped by a specific example. ,

e U. S. Nuclear Regul: tory Commission B16609/ Attachment 2/Page 10 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, NNECO has concluded that the proposed changes do not involve an SHC.

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ML20199D455

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