ML060790325

Proposed Revision to Technical Specifications (LBDCR 05-MP2-004) Pressurizer Water Level Limits

ML060790325
Person / Time
Site:	Millstone
Issue date:	03/17/2006
From:	Hartz L Dominion Nuclear Connecticut
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
05-430
Download: ML060790325 (21)

Text

Dominion Nuclear Connecticut, Inc.

5 0 0 0 Dominion Boulevard, Glen Allen, Virginia 23060 Web Address: www.dom.com March 17, 2006 U.S. Nuclear Regulatory Commission Serial No.05-430 Attention: Document Control Desk MPS LicIMAE R1 Washington, DC 20555 Docket No. 50-336 33650 License No. DPR-65 MILLSTONE POWER STATION UNIT 2 PROPOSED REVISION TO TECHNICAL SPECIFICATIONS

/LBDCR 05-MP2-004) PRESSURIZER WATER LEVEL LIMITS Pursuant to 10 CFR 50.90, Dominion Nuclear Connecticut, Inc. (DNC) hereby requests to amend Operating License DPR-65 for Millstone Power Station Unit 2 (MPS2). The enclosed license amendment request proposes to revise Technical Specification 3.4.4, "Reactor Coolant System Pressurizer." The proposed change replaces the existing maximum and minimum pressurizer water volume and water level limits with a maximum water level limit. This change removes ambiguity relative to parameters being monitored to support continuous plant operation.

The proposed amendment does not involve a significant impact on public health and safety and does not involve a significant hazards consideration pursuant to the provisions of 10 CFR 50.92.

The Site Operations Review Committee has reviewed and concurred with the determinations.

Attachment 1 contains description of the proposed technical specification (TS) change and the significant hazards consideration. Attachment 2 contains the TS marked-up pages, and Attachment 3 contains the retyped pages. Attachment 4 contains the marked-up pages of the TS Bases for information only. MPS2 TS Bases are controlled in accordance with TS Section 6.23, "Technical Specification Bases Control program."

DNC requests issuance of this amendment no later than January 30, 2007, with the amendment to be implemented within 60 days of issuance.

In accordance with 10 CFR 50.91 (b), a copy of this license amendment request is being provided to the State of Connecticut.

Serial No.05-430 Docket No. 50-336 Pressurizer Water Level Page 2 of 4 If you have any questions or require additional information, please contact Mr. Paul R.

Willoug hby at (804) 273-3572.

Very truly yours, J

Leslie N. Hartz Vice President - Nuclear Engineering

Serial No.05-430 Docket No. 50-336 Pressurizer Water Level Page 3 of 4 Attachments:

1. Evaluation of Proposed License Amendment

1. Marked-Up TS Pages

2. Re-typed TS Pages

3. Marked-Up Bases pages Commitments made in this letter: None.

cc: U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406-141 5 Mr. V. Nerses Senior Project Manager U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Mail Stop 8C2 Rockville, MD 20852-2738 Mr. S. M. Schneider NRC Senior Resident Inspector Millstone Power Station

Serial No.05-430 Docket No. 50-336 Pressurizer Water Level Page 4 of 4 COMMONWEALTH OF VIRGINIA )

1 COUNTY OF HENRICO )

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

Acknowledged before me this / 7 day of  ?~lahc/~, ,2006.

My Commission Expires: && 31. 2009.

7 k g d . dJjL Notary Pu lic (SEAL)

Serial No.05-430 Docket No. 50-336 ATTACHMENT 1 PROPOSED REVISION TO TECHNICAL SPECIFICATIONS

/LBDCR 05-MP2-004) PRESSURIZER WATER LEVEL LIMITS EVALUATION OF PROPOSED LICENSE AMENDMENT DOMINION NUCLEAR CONNECTICUT INC.

MILLSTONE POWER STATION UNIT 2

Serial No.05-430 Docket No. 50-336 Pressurizer Water Level Attachment 1 Page 1 of 10 EVALUATION OF PROPOSED LICENSE AMENDMENT

3.0 BACKGROUND

3.1 Pressurizer Description 3.2 Bases For Pressurizer Volume 3.3 Reason for the Proposed Amendment

4.0 TECHNICAL ANALYSIS

4.1 Details of the Proposed Amendment 4.2 Safety Summary

5.0 REGULATORY ANALYSIS

5.1 No Significant Hazards Consideration 5.2 Applicable Regulatory Requirements/Criteria

6.0 ENVIRONMENTAL CONSIDERATION

Serial No.05-430 Docket No. 50-336 Pressurizer Water Level Attachment 1 Page 2 of 10

1.0 DESCRIPTION

Pursuant to 10 CFR 50.90, Dominion Nuclear Connecticut, Inc. (DNC) hereby requests to amend Operating License DPR-65 for Millstone Power Station Unit 2 (MPS2). The enclosed license amendment request proposes to revise Technical Specification 3.4.4, "Reactor Coolant System Pressurizer." The proposed change replaces the existing maximum and minimum pressurizer water volume and water level limits with a maximum water level limit. This change removes ambiguity relative to parameters being monitored to support continuous plant operation. The associated technical specification bases will be updated to address the proposed changes. The proposed change is consistent with the improved standard technical specifications, NUREG 1432, Revision 3.

2.0 PROPOSED CHANGE

The proposed amendment will modify Technical Specification (TS) 314.4.4 as follows:

The current wording of Limiting Condition for Operation (LCO) 3.4.4a:

"a. A water volume greater than or equal to 525 cubic feet (35%) less than or equal to 1050 cubic feet (70%), and" is replaced with:

"a. Pressurizer water level 5 70%, and" The word "volume", in Surveillance Requirement (SR) 4.4.4.1, is also replaced with the word "level" to maintain consistency with the proposed change in the LCO.

Bases Chanaes Bases Section 314.4.4, "Pressurizer," is updated to reflect the proposed change.

3.0 BACKGROUND

3.1 Pressurizer Description The pressurizer maintains reactor coolant system (RCS) operating pressure and compensates for changes in coolant volume during load changes.

Pressure is maintained by controlling the temperature of the saturated liquid volume in the pressurizer. At full load nominal conditions, approximately 6l0I0of the pressurizer volume is occupied by saturated water, and the remainder by saturated steam. A number of the pressurizer heaters are operated continuously to offset the heat losses

Serial No.05-430 Docket No. 50-336 Pressurizer Water Level Attachment 1 Page 3 of 10 and the continuous minimum spray, thereby maintaining the steam and water in thermal equilibrium at the saturation temperature corresponding to the desired system pressure.

During load changes, the pressurizer limits pressure variations caused by expansion or contraction of the reactor coolant. The average reactor coolant temperature is programmed to vary as a function of load. A reduction in load is followed by a decrease in the average reactor coolant temperature to the programmed value for the lower power level. The resulting contraction of the coolant lowers the pressurizer water level causing the reactor system pressure to decrease. The pressure reduction is partially compensated by flashing of pressurizer water into steam. All pressurizer heaters are automatically energized on low system pressure, generating steam and further limiting pressure decrease. Should the water level in the pressurizer drop sufficiently below its setpoint, the let-down control valves close to a minimum value and additional charging pumps in the chemical and volume control system (CVCS) are automatically started to add coolant to the system and restore pressurizer level.

When steam demand is increased, the average reactor coolant temperature is raised in accordance with the coolant temperature program. The expanding coolant from the reactor coolant piping hot leg enters the bottom of the pressurizer (in-surge),

compressing the steam and raising system pressure. The increase in pressure is moderated by the condensation of steam during compression. Should the pressure increase be large enough, the pressurizer spray valves open, spraying coolant from the reactor coolant pump (RCP) discharge (cold leg) into the pressurizer steam space. The relatively cold spray water condenses some of the steam in the steam space, limiting the system pressure increase. The programmed pressurizer water level is a power-dependent function. A high level error signal produced by an in-surge causes the let-down control valves to open, releasing coolant to the CVCS and restoring the pressurizer to the prescribed level.

Small pressure and coolant volume variations are accommodated by the steam volume, which absorbs flow into the pressurizer and by the water volume, which allows flow out of the pressurizer. The water volume maintained in the pressurizer is determined by consideration of the following factors:

a. Sufficient water volume is necessary to prevent draining the pressurizer as the result of a reactor trip or a loss-of-load accident. In order to preclude the initiation of safety injection and of automatic injection of concentrated boric acid by the charging pumps, the pressurizer is designed so that the minimum pressure observed during such transients is above the setpoint of the safety injection actuation signal (SIAS);

b. The heaters should not be uncovered by the out-surge following load decreases; ten percent step decrease, and five percent per minute ramp decrease;

Serial No.05-430 Docket No. 50-336 Pressurizer Water Level Attachment 1 Page 4 of 10

c. The steam volume should be sufficient to yield acceptable pressure response to normal system volume changes during load change transients;

d. The water volume should be minimized to reduce the energy release and resultant containment pressure during a loss of coolant accident (LOCA);

e. The steam volume should be sufficient to accept the reactor coolant in-surge resulting from loss-of-load without the water level reaching the safety and power-operated relief valve (PORV) nozzles;

f. During load following transients, the total coolant volume change and associated charging and let-down flows should be kept as small as practical and be compatible with the capacities of the volume control tank, charging pumps, and let-down control valves in the CVCS.

To account for these factors and to provide adequate margin at all power levels, the water level in the pressurizer is programmed as a function of average coolant temperature. High or low water level error signals result in the control actions described above.

3.2 Bases For Maximum Pressurizer Level The plant is currently operated at an indicated pressurizer level less than or equal to 70% consistent with Technical Specification Limiting Condition for Operation 3.4.4. The maximum initial pressurizer water volume used in the FSAR Chapter 14 anticipated operational occurrences is based on this maximum indicated pressurizer water level of 70% plus an allowance for instrument uncertainty. Further detail on the initial pressurizer volume used in the FSAR Chapter 14 analyses is provided in Section 4.1.

3.3 Reason for the Proposed Amendment The proposed change modifies the required pressurizer level in MPS2 TS 3.4.4, "Reactor Coolant System Pressurizer" to eliminate the ambiguity regarding the parameter value monitored to support continuous plant operation. The technical justification for each proposed change is provided in Section 4.1.

4.0 TECHNICAL ANALYSIS

4.1 Details of the Proposed Amendment The enclosed license amendment request proposes to revise TS 3.4.4, "Reactor Coolant System Pressurizer." The proposed change eliminates the ambiguity regarding the parameter value monitored to support continuous plant operation. The associated technical specification bases will be updated to address the proposed changes.

Serial No.05-430 Docket No. 50-336 Pressurizer Water Level Attachment 1 Page 5 of 10 The current Limiting Condition for Operation 3.4.4a, sets operating limits for pressurizer water volume. During plant operations, the indicated pressurizer water level is currently maintained greater than or equal to 35% and less than or equal to 70% (i.e., control room instruments indicate pressurizer water level in percent, not in cubic feet).

The current operating limits will be removed and replaced with an upper limit of 5 70%

as read on the pressurizer level indicator. The maximum water level is being maintained in the Technical Specification Limiting Conditions for Operation as it satisfies Criterion 2 of 10 CFR 50.36(c)(2)(ii). The maximum level limit prevents filling the pressurizer during FSAR Chapter 14 anticipated operational occurrences, ensuring that the pressure relief devices (PORVs or pressurizer safety valves) can control pressure by steam relief rather than water relief, thereby preventing a challenge to the integrity of the RCS fission product barrier. The limiting FSAR Chapter 14 anticipated operational occurrence analyzed with respect to pressurizer overfill is the loss of normal feedwater event presented in FSAR 14.2.7. The initial pressurizer level for this event is based on the technical specification maximum pressurizer level of 70% with an additional allowance for instrument inaccuracy. The remaining FSAR Chapter 14 anticipated operational occurrences are not specifically analyzed with respect to pressurizer overfill, and assume an initial pressurizer level based on the normal operating pressurizer level for the assumed initial power level. If initiated from the maximum pressurizer level, none of these events would result in pressurizer overfill.

The minimum allowed pressurizer level currently in TS 3.4.4 is being deleted as it does not satisfy any of the 10 CFR 50.36(c)(2)(ii) criterion for inclusion in the Technical Specification Limiting Conditions for Operation.

10 CFR 50.36(c)(2)(ii) contains the requirements for items that must be in Technical Specification Limiting Conditions for Operation. This regulation provides four (4) criteria that can be used to determine the requirements that must be included in the Technical Specifications.

Criterion 1 Installed instrumentation that is used to detect, and indicate in the control room, a significant abnormal degradation of the reactor coolant pressure boundary.

This criterion addresses instrumentation installed to detect excessive RCS leakage. The existing minimum pressurizer level Limiting Condition for Operation in TS 3.4.4, which prevents uncovering the pressurizer heaters, does not cover installed instrumentation that is used to detect, and indicate in the control room, a significant degradation of the reactor coolant pressure boundary. The existing minimum pressurizer level Limiting Condition for Operation in TS 3.4.4 does not satisfy Criterion 1.

Serial No.05-430 Docket No. 50-336 Pressurizer Water Level Attachment 1 Page 6 of 10 Criterion 2 A process variable, design feature, or operating restriction that is an initial condition of a design basis accident or transient analysis that either assumes the failure of or presents a challenge to the integrity of a fission product barrier.

The purpose of this criterion is to capture those process variables that have initial values assumed in the design basis accident and transient analyses, and which are monitored and controlled during power operation. This criterion also includes active design features (e.g., high pressure/low pressure system valves and interlocks) and operating restrictions (pressure/temperature limits) needed to preclude unanalyzed accidents and transients.

The existing minimum pressurizer level limiting condition for operation is not an initial condition of a design basis accident that is required to prevent a challenge to the integrity of the fission product barriers. The current minimum level is a practical operating limit that prevents uncovering the pressurizer heaters. Maintaining steady state operation with the pressurizer heaters uncovered is not possible, as RCS subcooling cannot be maintained at the desired level in the long term due to heat loss. Therefore, the existing minimum pressurizer level limiting condition for operation does not cover a process variable, design feature, or operating restriction that is an initial condition of a design basis accident or transient analysis that either assumes the failure of or presents a challenge to the integrity of a fission product barrier. The existing minimum pressurizer level limiting condition for operation does not satisfy Criterion 2.

Criterion 3 A structure, system, or component that is part of the primary success path and which functions or actuates to mitigate a design basis accident or transient that either assumes the failure of or presents a challenge to the integrity of a fission product barrier.

The purpose of this criterion is to capture only those structures, systems, and components that are part of the primary success path of the safety analysis (an examination of the actions required to mitigate the consequences of the design basis accidents and transients). The primary success path of a safety analysis consists of the combinations and sequences of equipment needed to operate, so that the plant response to the design basis accidents and transients limits the consequences of these events to within the appropriate acceptance criteria. Also captured by this criterion are those support and actuation systems that are necessary for items in the primary success path to successfully function. It does not include backup and diverse equipment.

Serial No.05-430 Docket No. 50-336 Pressurizer Water Level Attachment 1 Page 7 of 10 The existing minimum pressurizer level limiting condition for operation is not credited in any MPS2 design basis accident (DBA) analysis that relies on the emergency core cooling system (ECCS) for accident mitigation. As a result, the existing minimum pressurizer level Limiting Condition for Operation in TS 3.4.4 does not cover a structure, system, or component that is part of the primary success path and which functions or actuates to mitigate a design basis accident or transient that either assumes the failure of or presents a challenge to the integrity of a fission product barrier. The existing minimum pressurizer level Limiting Condition for Operation in TS 3.4.4 does not satisfy Criterion 3.

Criterion 4 A structure, system, or component which operating experience or probabilistic risk assessment has shown to be significant to public health and safety.

The purpose of this criterion is to capture only those structures, systems, and components that operating experience or probabilistic risk assessment has shown to be significant to public health and safety. Requirements proposed for deletion do not contain constraints significant to public health or safety in limiting the likelihood or severity of the accident sequences that are commonly found to dominate risk.

The existing minimum pressurizer level Limiting Condition for Operation in TS 3.4.4, which prevents uncovering the pressurizer heaters, does not cover a constraint of significance to public health and safety in limiting the likelihood or severity of the accident sequences that are commonly found to dominate risk as defined in 10 CFR 50.36(c)(2)(ii) Criterion 4.

4.2 Safety Summary The proposed changes will remove the water volume values from the pressurizer level limits and retain only the required maximum level as read on the pressurizer level indicator. These changes are made to eliminate the ambiguity regarding the parameter value monitored to support continuous plant operation, and to delete the minimum pressurizer level as it does not satisfy any of the 10 CFR 50.36(c)(2)(ii) criteria for inclusion as a limiting condition for operation. The specific details of each proposed change are provided in Section 4.1. The proposed maximum pressurizer level limit is consistent with the current analysis. Since there is no change as to how the maximum pressurizer level is being maintained during plant operations, the margins of safety are maintained. Therefore, the proposed change has no adverse effect on plant safety.

Serial No.05-430 Docket No. 50-336 Pressurizer Water Level Attachment 1 Page 8 of 10

5.0 REGULATORY ANALYSIS

5.1 No Significant Hazards Consideration The proposed amendment deletes the water volume and percentage values from Millstone Power Station Unit 2 (MPS2) Limiting Condition for Operation 3.4.4a and replaces these values with a maximum percentage limit as read on the pressurizer water level indicator. Pressurizer water level is the parameter directly monitored during plant operation to ensure conformance with existing analysis assumptions. Additionally, only the maximum level is a limiting input to the MPS2 FSAR Chapter 14 analysis. This change maintains the current maximum operating pressurizer level at its present value.

In accordance with 10CFR50.92, Dominion Nuclear Connecticut, Inc. (DNC) has reviewed the proposed change and has concluded that it does not involve a significant hazards consideration (SHC). The basis for this conclusion is that the three criteria of 10CFR50.92(c) are not compromised as detailed below.

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

Response: No.

The proposed change is based on the accident analysis of record, which establishes an upper analytical limit for the pressurizer level based on the maximum allowable operating level with allowance for uncertainty. The proposed change maintains the current maximum operating pressurizer level at its present value. The lower limit is not significant to the analysis of record and has no importance to the probability of accident occurrence. The proposed change does not modify any plant equipment and does not impact any failure modes that could lead to an accident. It does not impact a method of operation or any operating limit. Additionally, the proposed change has no effect on the consequences of any analyzed accident since the change does not affect the function of any equipment credited for accident mitigation. Based on this discussion, the proposed amendment does not increase the probability or consequences of an accident previously evaluated.

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

Response: No.

The proposed change does not modify any plant equipment and there is no impact on the capability of existing equipment to perform its intended functions. No system setpoints are being modified and no changes are being made to the method in which plant operations are conducted. No new failure modes are introduced by the proposed change. Therefore, the proposed amendment does not create the

Serial No.05-430 Docket No. 50-336 Pressurizer Water Level Attachment 1 Page 9 of 10 possibility of a new or different kind of accident from any accident previously evaluated.

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

Response: No.

The proposed change is based on the accident analysis of record, which establishes an upper analytical limit for the pressurizer level based on the maximum allowable operating level with allowance for uncertainty. The proposed change maintains the current maximum operating pressurizer level at its present value. The lower limit is not significant to the analysis of record and has no importance to the probability of accident occurrence. The proposed change does not involve a reduction in a margin of safety because the acceptance criterion for the maximum pressurizer level is unchanged. For this reason, the proposed change does not affect any of the assumptions used in the accident analysis, nor does it affect any operability requirements for equipment important to plant safety.

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

5.2 Applicable Regulatory Requirementslcriteria The requirements of General Design Criterion (GDC) 15 of Appendix A to Title 10 of the Code of Federal Regulations Part 50 (10 CFR Part 50) state that "the reactor coolant system and associated auxiliary, control and protection systems shall be designed with sufficient margin to assure that the design conditions of the reactor coolant pressure boundary are not exceeded during any condition of normal operation, including anticipated operational occurrences." The pressurizer is a key component that assures compliance with GDC 15. The proposed change does not modify any plant equipment and there is no impact on the capability of existing equipment to perform its intended functions. Therefore, compliance with GDC 15 is maintained.

Additionally, the technical specification limiting condition of operation must satisfy the requirements of Section 10 CFR 50.36, which specifies the Commission's regulatory requirements related to the content of technical specifications. Specifically, 10 CFR 50.36(c)(2)(ii) sets forth four criteria to be used in determining whether a limiting condition for operation is required to be included in technical specifications. These criteria are: (1) installed instrumentation that is used to detect, and indicate in the control room, a significant abnormal degradation of the reactor coolant system pressure

Serial No.05-430 Docket No. 50-336 Pressurizer Water Level Attachment 1 Page 10 of 10 boundary; (2) initial plant conditions that are assumed in a design basis transient and accident analysis; (3) components or systems that are used for mitigating consequences of the design basis transient and accident; and (4) components or systems which probabilistic risk assessment has shown to be significant to public health and safety. Changes to Limiting Condition for Operation 3.4.4a ensure that compliance with the provisions of 10 CFR 50.36 is maintained.

6.0 ENVlRONMENTAL CONS1DERATION DNC has determined that the proposed amendment would change requirements with respect to use of a facility component located within the restricted area, as defined by 10 CFR 20, or it would change inspection or surveillance requirements. DNC has evaluated the proposed change and has determined that the change does not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluent that may be released off site, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed amendment meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(~)(9).Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.

Serial No.05-430 Docket No. 50-336 ATTACHMENT 2 PROPOSED REVISION TO TECHNICAL SPECIFICATIONS (LBDCR 05-MP2-004)

PRESSURIZER WATER LEVEL LIMITS TECHNICAL SPECIFICATIONS MARKED-UP PAGES DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2

REACTOR COOLANT SYSTEM PRESSURIZER LIMITING CONDITION FOR OPERATION 3.4,4 The p r e s s u r i z e r s h a l l be OPERABLE w i t h :

a.

b. A t l e a s t t w o groups o f p r e s s u r i z e r h e a t e r s each h a v i n g a c a p a c i t y of a t l e a s t 130 kW.

APPLICABILITY: MODES 1, 2 and 3.

ACT ION :

a. W i t h o n l y one group o f p r e s s u r i z e r h e a t e r s OPERABLE, r e s t o r e a t l e a s t two groups t o OPERABLE s t a t u s w i t h i n 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> o r be i n a t l e a s t HOT STANDBY w i t h i n t h e n e x t 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and i n HOT SHUTDOWN w i t h i n t h e f o l l o w i n g 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

b. W i t h t h e p r e s s u r i z e r otherwise inoperable, be i n a t l e a s t HOT STANDBY w i t h t h e r e a c t o r t r i p breakers open w i t h i n 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and i n HOT SHUTDOWN w i t h i n t h e f o l l o w i n g 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

SURVEILLANCE REQUIREMENTS w

4.4.4.1 The p r e s s u r i z e r water v&ww s h a l l be determined t o be w i t h i n i t s l i m i t s a t l e a s t once p e r 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

L 4.4.4.2 V e r i f y a t l e a s t two groups o f p r e s s u r i z e r h e a t e r s each have a c a p a c i t y o f a t l e a s t 130 kW a t l e a s t once p e r 92 days.

MILLSTONE - UNIT 2

Serial No.05-430 Docket No. 50-336 ATTACHMENT 3 PROPOSED REVISION TO TECHNICAL SPECIFICATIONS (LBDCR 05-MP2-004)

PRESSURIZER WATER LEVEL LIMITS TECHNICAL SPECIFICATIONS RE-TYPED PAGES DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2

REACTOR COOLANT SYSTEM PRESSURIZER LIMITING CONDITION FOR OPERATION 3.4.4 The pressurizer shall be OPERABLE with:

a. Pressurizer water level 5 70%, and

b. At least two groups of pressurizer heaters each having a capacity of at least 130 kW.

APPLICABILITY MODES l , 2 and 3.

ACTION:

a. With only one group of pressurizer heaters OPERABLE, restore at least two groups to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in HOT SHUTDOWN within the following 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

b. With the pressurizer otherwise inoperable, be in at least HOT STANDBY with the reactor trip breakers open within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

SURVEILLANCE REQUIREMENTS 4.4.4.1 The pressurizer water level shall be determined to be within its limits at least once per I 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

4.4.4.2 Verify at least two groups of pressurizer heaters each have a capacity of at least 130 kW at least once per 92 days.

MILLSTONE - UNIT 2 Amendment No. &,a, 47,M, 249, w,

Serial No.05-430 Docket No. 50-336 ATTACHMENT 4 PROPOSED REVISION TO TECHNICAL SPECIFICATIONS (LBDCR 05-MP2-004)

PRESSURIZER WATER LEVEL LIMITS BASES MARKED-UP PAGES DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2

314.4 REACTOR COOLANT SYSTEM BASES stuck open PORV at a time that the block valve is inoperable. This may be accomplished by various methods. These methods include, but are not limited to, placing the NORMALASOLATE switch at the associated Bottle Up Panel in the "ISOLATE" position or pulling the control power hses for the associated PORV control circuit.

Although the block valve may be designated inoperable, it may be able to be manually opened and closed and in this manner can be used to perform its function. Block valve inoperability may be due to seat leakage, instrumentation problems, or other causes that do not prevent manual use and do not create a possibility for a small break LOCA. This condition is only intended to permit operation of the plant for a limited period of time. The block valve should normally be available to allow PORV operation for automatic mitigation of overpressure events. The block valves must be returned to OPERABLE status prior to entering MODE 3 after a refueling outage.

a . -,

If more than one PORV is inoperable and not capable of being manually cycled, it is necessary to either restore at least one valve within the completion time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> or isolate the flow path by closing and removing the power to the associated block valve and cooldown the RCS to MODE 4.

314.4.4 PRESSURIZER An OPERABLE pressurizer provides pressure control for the reactor coolant system during operations with both forced reactor.coolant flow and with natural circulation flow. The

.% The maximum water level in the pressurizer ensures that this parameter is maintained within the envelope of operation assumed in the safety analysis. The maximum water level also ensures that the RCS is not a hydraulically solid system and that a steam bubble will be provided to accommodate pressure surges during operation. The steam bubble also protects the pressurizer code safety valves and power operated relief valve against water relief. The requirement that a minimum number of pressurizer heaters be OPERABLE enhances the capability of the plant to control Reactor Coolant System pressure and establish and

- maintain natural circulation.

The reqzrement for two groups of pressurizer heaters, each having a capacity of 130 kW, is met by verifying the capacity of the pressurizer proportional heater groups 1 and 2. Since the pressurizer proportional heater groups 1 and 2 are supplied from the emergency 480V electrical buses, there is reasonable assurance that these heaters can be energized during a loss of offsite power to maintain natural circulation at HOT STANDBY.

314.4.5 STEAM GENERATORS The Surveillance Requirements for inspection of the steam generator tubes ensure that the structural integrity of this portion of the RCS will be maintained. The program for inservice inspection of steam generator tubes is based on a modification of Regulatory Guide 1.83, Revision 1. Inservice inspection of steam generator tubing is essential in order to maintain surveillance of the conditions of the tubes in the event that there is MILLSTONE - UNIT 2 B 314 4-2a Amendment No. ?2,3?, 52,@i, 42,

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