Text

License Amendment Request to Revise Technical Specifications Regarding Generic Letter 2008-01, Managing Gas Accumulation in Accordance with TSTF-523, Revision 2, Using the Consolidated Line Item Improvement..
	ML15014A411
Person / Time
Site:	Hatch
Issue date:	01/13/2015
From:	Pierce C; Southern Co, Southern Nuclear Operating Co
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	GL-08-001, NL-14-1349
	Download: ML15014A411 (121)
	v • d • e

Charles R. Pierce Southern Nuclear Regulatory Affairs Director Operating Company, Inc.

40 Inverness Center Parkway Post Office Box 1295 Birmingham, AL 35201 Tel 205.992.7872 SOUTHERN Fax 205.992.7601 COMPA0Y JAN 1 3 2015 Docket Nos.: 50-321 NL-14-1349 50-366 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Edwin I. Hatch Nuclear Plant Units 1 and 2 License Amendment Request to Revise Technical Specifications Regarding Generic Letter 2008-01, Managing Gas Accumulation in accordance with TSTF-523, Revision 2, Using the Consolidated Line Item Improvement Process (CLIIP)

Ladies and Gentlemen:

In accordance with the provisions of 10 CFR 50.90 Southern Nuclear Operating Company (SNC) is submitting a request for an amendment to the technical specifications (TS) for Edwin I. Hatch Nuclear Plant (HNP), Units 1 and 2.

The proposed amendment would modify TS requirements related to Generic Letter 2008-01, "Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray systems," as described in TSTF-523, Revision 2, "Generic Letter 2008-01, Managing Gas Accumulation." SNC committed to submit this proposed change in Edwin I. Hatch Nuclear Plant Response to NRC Generic Letter 2008-1, "Response to Request for Additional Information," ML093480120. provides a description of the proposed changes, the requested confirmation of applicability, and plant-specific verifications. Enclosure 2 provides, the existing TS pages marked up to show the proposed changes. Enclosure 3 provides revised (clean) TS pages. Enclosure 4 provides existing TS Bases pages marked up to show the proposed changes.

SNC requests approval of the proposed license amendments by December 31, 2015. The proposed changes would be implemented within 120 days of issuance of the amendment.

In accordance with 10 CFR 50.91 (b)(1), "State Consultation," a copy of this application and its reasoned analysis about no significant hazards considerations is being provided to the designated Georgia officials.

A'3(e

U. S. Nuclear Regulatory Commission NL-14-1349 Page 2 This letter contains no NRC commitments. If you have any questions, please contact Ken McElroy at (205) 992-7369.

Mr. C. R. Pierce states he is Regulatory Affairs Director of Southern Nuclear Operating Company, is authorized to execute this oath on behalf of Southern Nuclear Operating Company and, to the best of his knowledge and belief, the facts set forth in this letter are true.

Respectfully submitted, C. R. Pierce Regulatory Affairs Director CRP/GKM/GLS Swn to and su cribed before me this *3 day of QŽ , 2015.

Notary Public My commission expires: 6 - oZo/7

Enclosures:

1. Basis for Proposed Change

2. HNP Technical Specification Marked Up Pages

3. HNP Technical Specification Clean Typed Pages

4. HNP Technical Specification Bases Marked Up Pages (for information only) cc: Southern Nuclear Operatinq Company Mr. S. E. Kuczynski, Chairman, President & CEO Mr. D. G. Bost, Executive Vice President & Chief Nuclear Officer Mr. D. R. Vineyard, Vice President - Hatch Mr. M. D. Meier, Vice President - Regulatory Affairs Mr. B. J. Adams, Vice President - Engineering Mr. D. R. Madison, Vice President - Fleet Operations Mr. G. L. Johnson, Regulatory Affairs Manager - Hatch RType: CHA02.004 U. S. Nuclear Re-gulatory Commission Mr. V. M. McCree, Regional Administrator Mr. R. E. Martin, NRR Senior Project Manager - Hatch Mr. D. H. Hardage, Senior Resident Inspector - Hatch State of Georgia Mr. J. H. Turner, Director Environmental Protection Division

Edwin I. Hatch Nuclear Plant License Amendment Request to Revise Technical Specifications Regarding GL 2008-01, Managing Gas Accumulation, Revision 2, Using the Consolidated Line Item Improvement Process (CLIIP)

Enclosure I Basis for Proposed Change to NL-14-1349 Basis for Proposed Change Table of Contents 1.0 Description 2.0 Assessment 3.0 Regulatory Analysis 4.0 Environmental Evaluation El-1 to NL-14-1349 Basis for Proposed Change

1.0 DESCRIPTION

The proposed change revises or adds Surveillance Requirements to verify that the system locations susceptible to gas accumulation are sufficiently filled with water and to provide allowances which permit performance of the verification. The changes are being made to address the concerns discussed in Generic Letter 2008-01, "Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems."

The proposed amendment is consistent with TSTF-523, Revision 2, "Generic Letter 2008-01, Managing Gas Accumulation." The availability of this TS improvement was published in the FederalRegisteron January 15, 2014 as part of the consolidated line item improvement process (CLIIP).

2.0 ASSESSMENT 2.1 Applicability of Published Safety Evaluation Southern Nuclear Operating Company (SNC) has reviewed the safety evaluation dated December 23, 2013 as part of the CLIIP. This review included a review of the NRC staff's evaluation, as well as the supporting information provided to support TSTF-523. As described in the subsequent paragraphs, SNC has concluded that the justifications presented in the TSTF proposal and the safety evaluation prepared by the NRC staff are applicable to Edwin I. Hatch Nuclear Plant (HNP), Units 1 and 2, and justify this amendment for the incorporation of the changes to the HNP Units 1 and 2 TS.

The Traveler and model Safety Evaluation discuss the applicable regulatory requirements and guidance, including the 10 CFR 50, Appendix A, General Design Criteria (GDC). HNP Unit 1 was not licensed to the 10 CFR 50, Appendix A, GDC. The HNP Unit 1 construction permit was received under the 70 general design criteria, as discussed in section F.3 of the UFSAR. (Appendix F has since been designated as historical). The HNP Unit 1 equivalents of the referenced GDCs in the model SE are:

10 CFR 50 Appendix A Criterion 1, "Quality Standards and Records" Structures, systems, and components important to safety shall be designed, fabricated, erected, and tested to quality standards commensurate with the importance of the safety functions to be performed. Where generally recognized codes and standards are used, they shall be identified and evaluated to determine their applicability, adequacy, and sufficiency and shall be supplemented or modified as necessary to assure a quality product in keeping with the required safety function. A quality assurance program shall be established and implemented in order to provide adequate assurance that these structures, systems, and components will satisfactorily perform their safety functions. Appropriate records of the design, fabrication, erection, and testing of structures, systems, and components important to safety shall be maintained by or under the control of the nuclear power unit licensee throughout the life of the unit.

E1-2 to NL-14-1349 Basis for Proposed Change HNP Unit 1 Equivalent: 1967 GDC Criterion 1, "Quality Standards" Those system and components of reactor facilities which are essential to the prevention of accidents which could affect the public health and safety or to mitigation of their consequences shall be identified and then designed, fabricated, and erected to quality standards that reflect the importance of the safety function to be performed. Where generally recognized codes or standards on design, materials, fabrication, and inspection are used, they shall be identified. Where adherence to such codes or standards does not suffice to assure a quality product in keeping with the safety function, they shall be supplemented or modeled a necessary. Quality assurance programs, test procedures, and inspection acceptance levels to be used shall be identified. A showing of sufficiency and applicability of codes, standards, quality assurance programs, test procedures, and inspection acceptance levels used is required.

10 CFR 50 Appendix A Criterion 34, "Residual Heat Removal" A system to remove residual heat shall be provided. The system safety function shall be to transfer fission product decay heat and other residual heat from the reactor core at a rate such that specified acceptable fuel-design limits and the design conditions of the RCPB are not exceeded.

Suitable redundancy in components and features and suitable interconnections, leak detection, and isolation capabilities shall be provided to assure that, for onsite electric power system operation (assuming offsite power is not available) and for offsite electric power system operation (assuming onsite power is not available), the system safety function can be accomplished, assuming a single failure.

HNP Unit 1 does not have a distinct individual standalone 1967 Equivalent to 10 CFR 50 Appendix A Criterion 34 "Residual Heat Removal." However, the function /

requirement of this system are enveloped in to the HNP Unit 1 Equivalent: 1967 GDC Criterion 44, "Emergency Core Cooling Systems Capability (Category A)" and the HNP Unit 1 Equivalent: 1967 GDC Criterion 52, "Containment Heat Removal Systems (Category A)". HNP Unit 1 Equivalent: 1967 GDC Criterion 39, "Emergency Power for Engineered Safety Features (Category A)" and HNP Unit 1 Equivalent:

1967 GDC Criterion 41, "Engineered Safety Features Performance Capability (Category A)" can also be credited to ensure proper emergency power and the safety feature design assumes a failure of a single active component. These criterions are listed as follows:

HNP Unit 1 Equivalent: 1967 GDC Criterion 44, "Emergency Core Cooling Systems Capability (Category A)"

At least two emergency core cooling systems, preferably of different design principles, each with a capability for accomplishing abundant emergency core cooling, shall be provided. Each emergency core cooling system and the core shall be designed to prevent fuel and clad damage that would interfere with the two emergency core cooling function and to limit the clad metal-water reaction to negligible amounts for all sizes of breaks in the reactor coolant pressure boundary including the double-ended rupture of the largest pipe. The performance of each emergency core cooling system shall be evaluated E1-3 to NL-14-1349 Basis for Proposed Change conservatively in each area of uncertainty. The systems shall not share active components and shall not share other features or components unless it can be demonstrated that (a) the capability of the shared feature or component to perform its required function can be readily ascertained during reactor operation, (b) failure of the shared feature or component does not initiate a loss-of-coolant accident, and (c) capability of the shared feature or component to perform its required function is not impaired by the effects of a loss-of coolant accident and is not lost during the entire period this function is required following the accident.

HNP Unit 1 Equivalent: 1967 GDC Criterion 52, "Containment Heat Removal Systems (Category A)"

Where active heat removal systems are needed under accident conditions to prevent exceeding containment design pressure, at least two systems, preferably of different principles, each with full capacity, shall be provided.

HNP Unit 1 Equivalent: 1967 GDC Criterion 39, "Emergency Power for Engineered Safety Features (Category A)"

Alternate power systems shall be provided and designed with adequate independency, redundancy, capacity, and testability, to permit the functioning required of the engineered safety features. As a minimum, the onsite power system and the offsite power system shall each, independently, provide this capacity assuming a failure of a single active component in each power system.

HNP Unit 1 Equivalent: 1967 GDC Criterion 41, "Engineered Safety Features Performance Capability (Category A)"

Engineered safety features such as emergency core cooling and containment heat removal systems shall provide sufficient performance capability to accommodate partial loss of installed capacity and still fulfill the required function.

As a minimum, each engineered safety feature shall provide this required safety function assuming a failure of a single active component.

10 CFR 50 Appendix A Criterion 35, "Emergency Core Cooling" A system to provide abundant emergency core cooling shall be provided. The system safety function shall be to transfer heat from the reactor core following any loss of reactor coolant at a rate such that fuel and clad damage that could interfere with continued effective core cooling is prevented and clad metal water reaction is limited to negligible amounts.

Suitable redundancy in components and features and suitable interconnections, leak detection, isolation, and containment capabilities shall be provided to assure that, for onsite electric power system operation (assuming offsite power is not available) and for offsite electric power system operation (assuming onsite power is not available), the system safety function can be accomplished, assuming a single failure.

E1-4 to NL-14-1349 Basis for Proposed Change HNP Unit 1 Equivalent: 1967 GDC Criterion 44, "Emergency Core Cooling Systems Capability (Category A)"

At least two emergency core cooling systems, preferably of different design principles, each with a capability for accomplishing abundant emergency core cooling, shall be provided. Each emergency core cooling system and the core shall be designed to prevent fuel and clad damage that would interfere with the two emergency core cooling function and to limit the clad metal-water reaction to negligible amounts for all sizes of breaks in the reactor coolant pressure boundary including the double-ended rupture of the largest pipe. The performance of each emergency core cooling system shall be evaluated conservatively in each area of uncertainty. The systems shall not share active components and shall not share other features or components unless it can be demonstrated that (a) the capability of the shared feature or component to perform its required function can be readily ascertained during reactor operation, (b) failure of the shared feature or component does not initiate a loss-of-coolant accident, and (c) capability of the shared feature or component to perform its required function is not impaired by the effects of a loss-of coolant accident and is not lost during the entire period this function is required following the accident.

HNP Unit 1 Equivalent: 1967 GDC Criterion 39, "Emergency Power for Engineered Safety Features (Category A)"

Alternate power systems shall be provided and designed with adequate independency, redundancy, capacity, and testability, to permit the functioning required of the engineered safety features. As a minimum, the onsite power system and the offsite power system shall each, independently, provide this capacity assuming a failure of a single active component in each power system.

HNP Unit 1 Equivalent: 1967 GDC Criterion 41, "Engineered Safety Features Performance Capability (Category A)"

Engineered safety features such as emergency core cooling and containment heat removal systems shall provide sufficient performance capability to accommodate partial loss of installed capacity and still fulfill the required function.

As a minimum, each engineered safety feature shall provide this required safety function assuming a failure of a single active component.

10 CFR 50 Appendix A Criterion 36, "Inspection of Emergency Core Cooling Systems" The ECCS shall be designed to permit appropriate periodic inspection of important components, e.g., spray rings in the RPV, water injection nozzles, and piping, to assure the integrity and capability of the system.

E1-5 to NL-14-1349 Basis for Proposed Change HNP Unit 1 Equivalent: 1967 GDC Criterion 45, "Inspection of Emergency Core Cooling Systems Capability (Category A)"

Design provisions shall be made to facilitate physical inspection of all critical parts of the emergency core cooling systems, including reactor vessel internals and water injection nozzles.

10 CFR 50 Appendix A Criterion 37, "Testing of Emergency Core Cooling Systems" The ECCSs shall be designed to permit appropriate periodic pressure and functional testing to assure the following: a) Structural and leaktight integrity of its components. b) Operability and performance of the active components of the system. c) Operability of the system as a whole and, under conditions as close to design as practical, the performance of the full operational sequence that brings the system into operation, including operation of applicable portions of the protection system, the transfer between normal and emergency power sources, and the operation of the associated cooling water system.

HNP Unit 1 Equivalent: 1967 GDC Criterion 46, "Testing of Emergency Core Cooling Systems Components (Category A)"

Design provisions shall be made so that active components of the emergency core cooling systems, such as pumps and valves, can be tested periodically for operability and required functional performance.

HNP Unit 1 Equivalent: 1967 GDC Criterion 47, "Testing of Emergency Core Cooling Systems (Category A)"

A capability shall be provided to test periodically the delivery capability of the emergency core cooling systems at a location as close to the cores as is practical.

HNP Unit 1 Equivalent: 1967 GDC Criterion 48, "Testing of Operational Sequence of Emergency Core Cooling Systems (Category A)"

A capability shall be provided to test under conditions as close to design as practical the full operational sequence that would bring the emergency core cooling systems into action, including the transfer to alternate power sources.

10 CFR 50 Appendix A Criterion 38, "Containment Heat Removal" A system to remove heat from the reactor containment shall be provided. The system safety function shall be to reduce rapidly, consistent with the functioning of other associated systems, the containment pressure and temperature following any LOCA and to maintain them at acceptably low levels.

Suitable redundancy in components and features and suitable interconnections, leak detection, isolation, and containment capabilities shall be provided to assure that, for onsite electric power system operation (assuming offsite power is not available) and for offsite electric power system operation (assuming onsite power is not available), the system safety function can be accomplished, assuming a single failure.

E1-6 to NL-14-1349 Basis for Proposed Change HNP Unit 1 Equivalent: 1967 GDC Criterion 52, "Containment Heat Removal Systems (Category A)"

Where active heat removal systems are needed under accident conditions to prevent exceeding containment design pressure, at least two systems, preferably of different principles, each with full capacity, shall be provided.

HNP Unit 1 Equivalent: 1967 GDC Criterion 39, "Emergency Power for Engineered Safety Features (Category A)"

Alternate power systems shall be provided and designed with adequate independency, redundancy, capacity, and testability, to permit the functioning required of the engineered safety features. As a minimum, the onsite power system and the offsite power system shall each, independently, provide this capacity assuming a failure of a single active component in each power system.

HNP Unit 1 Equivalent: 1967 GDC Criterion 41, "Engineered Safety Features Performance Capability (Category A)"

Engineered safety features such as emergency core cooling and containment heat removal systems shall provide sufficient performance capability to accommodate partial loss of installed capacity and still fulfill the required function.

As a minimum, each engineered safety feature shall provide this required safety function assuming a failure of a single active component.

10 CFR 50 Appendix A Criterion 39, "Inspection of Containment Heat Removal System" The containment heat removal system (CHRS) shall be designed to permit appropriate periodic inspection of important components, such as the torus, sumps, spray nozzles, and piping, to ensure the integrity and capability of the system.

HNP Unit 1 Equivalent: 1967 GDC Criterion 58, "Inspection of Containment Pressure-Reducing Systems (Category A)"

Design provisions shall be made to facilitate the periodic physical inspection of all important components of the containment pressure-reducing systems, such as, pumps, valves, spray nozzles, torus and sumps.

10 CFR 50 Appendix A Criterion 40, "Testing of Containment Heat Removal System" The CHRS shall be designed to permit appropriate periodic pressure and functional testing to ensure the following: a) Structural and leaktight integrity of its components. b) Operability and performance of the active components. c)

Operability of the system as a whole and, under conditions as close to the design as practical, the performance of the full operational sequence that brings the system into operation, including operation of applicable portions of the protection system, the transfer between normal and emergency power sources, and the operation of the associated cooling water system.

E1-7 to NL-14-1349 Basis for Proposed Change HNP Unit 1 Equivalent: 1967 GDC Criterion 59, "Testing of Containment Pressure-Reducing Systems Components (Category A)"

The containment pressure-reducing systems shall be designed so that active components, such as pumps and valves, can be tested periodically for operability and required functional performance.

HNP Unit 1 Equivalent: 1967 GDC Criterion 60, "Testing of Containment Spray Systems Components (Category A)"

A capability shall be provided to test periodically the delivery capability pf the containment spray system at a position as close to the spray nozzle as practical.

HNP Unit 1 Equivalent: 1967 GDC Criterion 61, 'Testing of Operational Sequence of Pressure-Reducing Systems Components (Category A)"

A capability shall be provided to test under conditions as close to the design as practical the full operational sequence that would bring the containment pressure-reducing systems into action, including the transfer to alternate power sources.

Therefore, these differences do not alter the conclusion that the proposed change is applicable to HNP Unit 1.

HNP Unit 2 was licensed under the 10 CFR 50, Appendix A GDC.

SNC has concluded that the justifications presented in the TSTF-523 proposal and the model safety evaluation prepared by the NRC staff is applicable to Hatch Unit 1 and 2 and justify this amendment for the incorporation of the changes to the Hatch TS.

2.2 Optional Changes and Variations SNC is proposing the following variations from the TS changes described in the TSTF-523, Revision 2, or the applicable parts of the NRC staff's model safety evaluation dated December 23, 2013.

HNP Units 1 and 2 TS utilize different numbering than the Standard Technical Specifications on which TSTF-523 was based. Specifically, RHR Shutdown Cooling System - Hot Shutdown is section 3.4.7 at HNP Units 1 and 2 instead of section 3.4.8 per TSTF-523.

Also, RHR Shutdown Cooling System - Cold Shutdown is section 3.4.8 at HNP Units 1 and 2 instead of section 3.4.9 per TSTF-523. SR 3.6.2.5.2 was added to reflect addition of managing gas accumulation in the RHR Drywell Spray System section for both HNP Units 1 and 2. The RHR Drywell Spray System was not included in the generic TSTF-523, Revision 2 proposed change, but the RHR Drywell Spray System is an RHR system at HNP and is applicable to GL 2008-01 and the associated change to the TS.

RHR - High Water Level is section 3.9.7 at HNP Units 1 and 2 instead of section 3.9.8 per TSTF-523. Also, RHR - Low Water Level is section 3.9.8 at HNP Units 1 and 2 instead of section 3.9.9 per TSTF-523.

TSTF-523, Revision 2, Section 3.1, "Revise or Add Surveillance Requirements, states:

"Some LCOs only require one train or loop of DHR/RHR/SDC to be Operable at a given time. The proposed SR for those TS state "Verify the required [system]

El -8 to NL-14-1349 Basis for Proposed Change

[loop/train/subsystem] locations..." In the ISTS, the term "required" means "required by the LCO." The word "required" is added as a convention to avoid confusion since SRs are not applicable to equipment that is not required to be Operable. Corresponding changes are made to the Bases. HNP included the term "required" for the following SRs: TSs 3.4.7, 3.4.8, 3.9.7 and 3.9.8.

HNP Units 1 and 2 RHR Shutdown Cooling System Technical Bases sections for SR 3.4.7.2, SR 3.4.8.2, SR 3.9.7.2, and SR 3.9.8.2 have an administrative variation to TSTF-523, Revision 2 due to site specific plant configuration and existing surveillances.

The Technical Bases for the note added for SR 3.5.1.2, SR 3.5.2.4, and SR 3.5.3.2 explaining the site process for administratively controlling opening vent flow paths is clarified for HNP Units 1 and 2.

SNC has reviewed these changes discussed above and determined they are administrative and do not affect the applicability of TSTF-523 to the HNP Units 1 and 2 TS.

3.0 REGULATORY ANALYSIS

3.1 No Significant Hazards Consideration Determination SNC requests adoption of TSTF-523, Rev. 2, "Generic Letter 2008-01, Managing Gas Accumulation," which is an approved change to the standard technical specifications (STS), into the Hatch Unit 1 and 2 technical specifications (TS). The proposed change revises or adds Surveillance Requirements to verify that the system locations susceptible gas accumulation are sufficiently filled with water and to provide allowances which permit performance of the verification.

SNC has evaluated whether or not a significant hazards consideration is involved with the proposed amendment(s) by focusing on the three standards set forth in 10 CFR 50.92, "Issuance of amendment," as discussed below:

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

Response: No.

The proposed change revises or adds Surveillance Requirement(s) (SRs) that require verification that the Emergency Core Cooling System (ECCS), the Residual Heat Removal (RHR) System, the RHR Shutdown Cooling (SDC) System, the Containment Spray (CS) System, and the Reactor Core Isolation Cooling (RCIC)

System are not rendered inoperable due to accumulated gas and to provide allowances which permit performance of the revised verification. Gas accumulation in the subject systems is not an initiator of any accident previously evaluated. As a result, the probability of any accident previously evaluated is not significantly increased. The proposed SRs ensure that the subject systems continue to be capable to perform their assumed safety function and are not rendered inoperable due to gas accumulation.

Thus, the consequences of any accident previously evaluated are not significantly increased.

Therefore, the proposed change does not involve a significant increase in the probability E1-9 to NL-14-1349 Basis for Proposed Change or consequences of an accident previously evaluated.

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

Response: No.

The proposed change revises or adds SRs that require verification that the ECCS, the RHR, the RHR SDC System, the CS System, and the RCIC System are not rendered inoperable due to accumulated gas and to provide allowances which permit performance of the revised verification. The proposed change does not involve a physical alteration of the plant (i.e., no new or different type of equipment will be installed) or a change in the methods governing normal plant operation. In addition, the proposed change does not impose any new or different requirements that could initiate an accident. The proposed change does not alter assumptions made in the safety analysis and is consistent with the safety analysis assumptions.

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

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

Response: No.

The proposed change revises or adds SRs that require verification that the ECCS, the RHR, RHR SDC System, the CS System, and the RCIC System are not rendered inoperable due to accumulated gas and to provide allowances which permit performance of the revised verification. The proposed change adds new requirements to manage gas accumulation in order to ensure the subject systems are capable of performing their assumed safety functions. The proposed SRs are more comprehensive than the current SRs and will ensure that the assumptions of the safety analysis are protected. The proposed change does not adversely affect any current plant safety margins or the reliability of the equipment assumed in the safety analysis. Therefore, there are no changes being made to any safety analysis assumptions, safety limits or limiting safety system settings that would adversely affect plant safety as a result of the proposed change.

Therefore, the proposed change does not involve a significant reduction in a margin of safety.

Based on the above, SNC concludes that the proposed change presents no significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of "no significant hazards consideration" is justified.

4.0 ENVIRONMENTAL EVALUATION The proposed change would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or would change an inspection or surveillance requirement. However, the proposed change does not El-10 to NL-14-1349 Basis for Proposed Change involve (i) a significant hazards consideration, (ii) a significant change in the types or a significant increase in the amounts of any effluent that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure.

Accordingly, the proposed change meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed change.

El-11

Edwin I. Hatch Nuclear Plant License Amendment Request to Revise Technical Specifications Regarding GL 2008-01, Managing Gas Accumulation, Revision 2, Using the Consolidated Line Item Improvement Process (CLIIP)

Enclosure 2 HNP Technical Specification Marked Up Pages to NL-14-1349 HNP Technical Specification Marked Up Pages RHR Shutdown Cooling System - Hot Shutdown 3.4.7 CZHPX/PS V 1 LAflr1 P l..S.MtJI SIIVIIKlI S SURVEILLANCE FREQUENCY 4-SR 3.4.7.1 --------.- ...--------.----- NOTE------------

Not required to be met until 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months after reactor steam dome pressure is less than the RHR low pressure permissive pressure.

Verify one RHR shutdown cooling subsystem or In accordance with recirculation pump is operating. the Surveillance Frequency Control

/ Program

/

SR 3.4.7.2 Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam dome pressure is less than the RHR low pressure permissive pressure.

Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 1 3.4-15 Amendment No. 266 1 to NL-14-1349 HNP Technical Specification Marked Up Pages RHR Shutdown Cooling System - Cold Shutdown 3.4.8 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME B. No RHR shutdown cooling B.1 Verify reactor coolant 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery subsystem in operation. circulation by an of no reactor coolant alternate method. circulation AND AND No recirculation pump in operation. Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter AND B.2 Monitor reactor coolant Once per hour temperature.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.8.1 Verify one RHR shutdown cooling subsystem or In accordance with recirculation pump is operating. the Surveillance Frequency Control Program SR 3.4.8.2 Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 1 3.4-17 Amendment No. 2-66 1 to NL-14-1349 HNP Technical Specification Marked Up Pages ECCS - Operating locations susceptible to gas accumulation are 3.5.1 sufficiently filled with water.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.1.1 Verify, for each ECCS injection/spray subsystem, In accordance with the piping is filled with water" from the pump the Surveillance diScharge valve to the injection valve. Frequency Control Program SR 3.5.1.2 --- -----...-----.------ NOTE-'-- .---------- -........... .

[ .. Low pressure coolant injection (LPCI) subsystems LJ may be considered OPERABLE during alignment and operation for decay heat removal with reactor steam dome pressure less than the Residual Heat Removal (RHR) low pressure permissive pressure in MODE 3, ifcapable of being manually realigned and not otherwise inoperable.

Verify each ECCS injection/spray subsystem In accordance with manual, power operated, and automatic valve in the Surveillance 7the flow path, that is not locked, sealed, or Frequency Control

\otherwise secured in position, is in the correct Program position.

SR 3.5.1.3 Verify ADS air supply header pressure is In accordance with

> 90 psig. the Surveillance Frequency Control Program SR 3.5.1.4 Verify the RHR System cross tie valve is closed In accordance with and power is removed from the valve operator. the Surveillance Frequency Control Program S R 3.5.1.5 *(Not used.)

(continued)

2. Not required to be met for system vent flowpaths opened under administrative control.

HATCH UNIT 1 3.5-3 Amendment No. 2-66 1 to NL-14-1349 HNP Technical Specification Marked Up Pages ECCS - Shutdown locations susceptible to gas accumulation are 3.5.2 sufficiently filled with water.

SURVEILLANCE REQUIREMENTS (continued) _

SURVEILLANCE FREQUENCY SR 3.5.2.3 Verify, for eac uired ECCS injection/ spray In accordance with subsystem, is fulled with water from the

,e-.pi.ping the Surveillance pump discrg the injection valve. Frequency Control Program SR 3.5.2.4 -------- E- ----------

Y..One LPCI subsystem may be considered LDiQOPERABLE during alignment and operation for decay heat removal if capable of being manually realigned and not otherwise inoperable.

Verify each required ECCS injection/spray In accordance with subsystem manual, power operated, and the Surveillance automatic valve in the flow path, that is not locked, Frequency Control sealed, or otherwise secured in position, is in the Program correct position.

SR 3.5.2.5 Verify each required ECCS pump develops the In accordance with specified flow rate against a system head the Inservice corresponding to the specified reactor pressure. Testing Program SYSTEM HEAD CORRESPONDING NO. OF TO A REACTOR SYSTEM FLOW RATE PUMPS PRESSURE OF CS > 4250 gpm 1 > 113 psig LPCI > 7700 gpm 1 > 20 psig SR 3.5.2.6 .......... ......- NOTE -..... ..... ........

Vessel injection/spray may be excluded.

Verify each required ECCS injection/spray In accordance with subsystem actuates on an actual or simulated the Surveillance automatic initiation signal. Frequency Control Program

2. Not required to be met for system vent flowpaths opened under administrative control.

HATCH UNIT 1 3.5-8 Amendment No.-266 I

Enclosure 2 to NL-14-1349 HNP Technical Specification Marked Up Pages RCIC System locations susceptible to gas accumulation are 3.5.3 sufficiently filled with water.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.3.1 Verify the RCIC System .... g is filled With '-ter In accordance with from, the pump dichrge valve to the injection the Surveillance val. Frequency Control Program SR 3.5.3.2 Verify each RCIC System manual, power In accordance with operated, and automatic valve in the flow path, the Surveillance that is not locked, sealed, or otherwise secured in Frequency Control position, is in the correct position. Program SR 3.5.3.3 ---------.----.-.------ NOTE --.--..------.----------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure and flow are adequate to perform the test.

Verify, with reactor pressure < 1058 psig and In accordance with

> 920 psig, the RCIC pump can develop a flow the Surveillance rate > 400 gpm against a system head Frequency Control corresponding to reactor pressure. Program SR 3.5.3.4 ------ NOTE ---- ......-------------------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure and flow are adequate to perform the test.

Verify, with reactor pressure < 165 psig, the RCIC In accordance with pump can develop a flow rate > 400 gpm against a the Surveillance system head corresponding to reactor pressure. Frequency Control Program SR 3.5.3.5 ---- NOTE --........------------------

Vessel injection may be excluded.

Verify the RCIC System actuates on an actual or In accordance with simulated automatic initiation signal. the Surveillance NOTE ........

Frequency Control Not required to be met for system vent flow paths Program opened under administrative control.

HATCH UNIT 1 3.5-10 Amendment No.-266 to NL-14-1349 HNP Technical Specification Marked Up Pages RHR Suppression Pool Cooling 3.6.2.3 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.2.3.2 Verify each required RHR pump develops a flow In accordance with rate > 7700 gpm through the associated heat the Inservice exchanger while operating in the suppression pool Testing Program cooling mode.

SR 3.6.2.3.2 Verify RHR suppression pool cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 1 3.6-26 Amendment No. 4-95 I to NL-14-1349 HNP Technical Specification Marked Up Pages RHR Suppression Pool Spray 3.6.2.4 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.2.4 Verify each suppression pool spray nozzle is In accordance with unobstructed. the Surveillance Frequency Control Program SR 3.6.2.4.2 Verify RHR suppression pool spray subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 1 3.6-28 Amendment No. 266 to NL-14-1349 HNP Technical Specification Marked Up Pages RHR Drywell Spray 3.6.2.5 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY 3.6.2.5.2 Verify each drywell spray nozzle is unobstructed. Following maintenance which could result in nozzle blockage.

SR 3.6.2.5.2 Verify RHR drywell spray subsystem locations In accordance with susceptible to gas accumulation are sufficiently the Surveillance filled with water. Frequency Control Program HATCH UNIT 1 3.6-30 Amendment No. 2-,% 1 to NL-14-1349 HNP Technical Specification Marked Up Pages RHR - High Water Level 3.9.7 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME B. (continued) B.3 Initiate action to restore Immediately required standby gas treatment subsystem(s) to OPERABLE status.

AND B.4 Initiate action to restore Immediately isolation capability in each required secondary containment penetration flow path not isolated.

C. No RHR shutdown cooling C.1 Verify reactor coolant 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery subsystem in operation. circulation by an of no reactor coolant alternate method. circulation AND Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter AND C.2 Monitor reactor coolant Once per hour temperature.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.9.7.1 Verify one RHR shutdown cooling subsystem is In accordance with operating. the Surveillance Frequency Control Program SR 3.9.7.2 Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 1 3.9-10 Amendment No. 266 1 to NL-14-1349 HNP Technical Specification Marked Up Pages RHR - Low Water Level 3.9.8 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME B. (continued) B.3 Initiate action to restore Immediately isolation capability in each required secondary containment penetration flow path not isolated.

C. No RHR shutdown cooling C.1 Verify reactor coolant 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery subsystem in operation. circulation by an of no reactor coolant alternate method. circulation AND Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter AND C.2 Monitor reactor coolant Once per hour temperature.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.9.8.1 Verify one RHR shutdown cooling subsystem is In accordance with operating. the Surveillance Frequency Control Program SR 3.9.8.2 Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 1 3.9-12 Amendment No.-2-66 to NL-14-1349 HNP Technical Specification Marked Up Pages RHR Shutdown Cooling System - Hot Shutdown 3.4.7

.I IR\FIIl I AMt.F= PFC=I lIPPMFNI=Tq SURVEILLANCE FREQUENCY SR 3.4.7.1 Not required to be met until 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months after reactor steam dome pressure is less than the RHR low pressure permissive pressure.

Verify one RHR shutdown cooling subsystem or In accordance with recirculation pump is operating. the Surveillance Frequency Control Program SR 3.4.7.2 .... .....-.......... NOTE -

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam dome pressure is less than the RHR low pressure permissive pressure.

Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 2 3.4-15 Amendment No. 240 1 to NL-14-1349 HNP Technical Specification Marked Up Pages RHR Shutdown Cooling System - Cold Shutdown 3.4.8 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME B. No RHR shutdown cooling B.1 Verify reactor coolant 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery subsystem in operation. circulation by an of no reactor coolant alternate method. circulation AND AND No recirculation pump in operation. Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter AND B.2 Monitor reactor coolant Once per hour temperature.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.8.1 Verify one RHR shutdown cooling subsystem or In accordance with recirculation pump is operating. the Surveillance Frequency Control Program SR 3.4.8.2 Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 2 3.4-17 Amendment No. 240 1 to NL-14-1349 HNP Technical Specification Marked Up Pages ECCS - Operating locations susceptible to gas accumulation are 3.5.1 sufficiently filled with water.

SURVEILLANCE REQUIREMENTS SURVEILLANCE m FREQUENCY SR 3.5.1.1 Verify, for each ECCS injection/spray subsystem, In accordance with the piping

,, fille-

- th Wate. frM the pump the Surveillance di, harge valve to the injetio val. Frequency Control Program SR 3.5.1.2 .--- ---.-.---------.-- NOTE-----------

I[ j..Low 1 pressure coolant injection (LPCI) subsystems may be considered OPERABLE during alignment and operation for decay heat removal with reactor steam dome pressure less than the Residual Heat Removal (RHR) low pressure permissive pressure in MODE 3, if capable of being manually realigned and not otherwise inoperable.

Verify each ECCS injection/spray subsystem In accordance with manual, power operated, and automatic valve in the Surveillance the flow path, that is not locked, sealed, or Frequency Control

\ otherwise secured in position, is in the correct Program

~position.

SR 3.5.1.3 Verify ADS air supply header pressure is In accordance with

> 90 psig. the Surveillance Frequency Control Program SR 3.5.1.4 Verify the RHR System cross tie valve is closed In accordance with and power is removed from the valve operator. the Surveillance Frequency Control Program SR 3.5.1.5 (Not used.)

(continued)

2. Not required to be met for system vent flowpaths opened under administrative control.

HATCH UNIT 2 3.5-3 Amendment No. 24-01 to NL-14-1349 HNP Technical Specification Marked Up Pages ECCS - Shutdown locations susceptible to gas accumulation are 3.5.2 sufficiently filled with water.

SURVEILLANCE REQUIREMENTS (continued) ,_

SURVEILLANCE FREQUENCY SR 3.5.2.3 Verify, for eac: uired ECCS injection/spray In accordance with subsystem, ..e pep!-.g is filled with water from the the Surveillance pump d,4i*,h,.. l.e the in,,jet*,in valve. Frequency Control Program S.R 3.5.2.4 ------ NOTEI--_

LkJ-One LPCI subsystem may be considered OPERABLE during alignment and operation for decay heat removal if capable of being manually realigned and not otherwise inoperable.

Verify each required ECCS injection/spray In accordance with subsystem manual, power operated, and the Surveillance automatic valve in the flow path, that is not locked, Frequency Control sealed, or otherwise secured in position, is in the Program correct position.

SR 3.5.2.5 Verify each required ECCS pump develops the In accordance with specified flow rate against a system head the Inservice corresponding to the specified reactor pressure. Testing Program SYSTEM HEAD CORRESPONDING NO. OF TO A REACTOR SYSTEM FLOW RATE PUMPS PRESSURE OF CS > 4250 gpm 1 >l113 psig LPCI > 7700 gpm 1 > 20 psig S R 3.5.2.6 ---- -------- --NOTE --.-.-...--.-.-..-..-.-.......-

Vessel injection/spray may be excluded.

Verify each required ECCS injection/spray In accordance with subsystem actuates on an actual or simulated the Surveillance automatic initiation signal. Frequency Control Program

2. Not required to be met for system vent flowpaths opened under administrative control.

HATCH UNIT 2 3.5-9 Amendment No. 24-01

Enclosure 2 to NL-14-1349 HNP Technical Specification Marked Up Pages RCIC System locations susceptible to gas accumulation are 3.5.3 sufficiently filled with water.

SURVEILLANCE REQUIREMENTS /

SURVEILLANCE / FREQUENCY SR 3.5.3.1 Verify the RCIC System ,ng is filled -Wth -water In accordance with from the pump icag valve to the iecon the Surveillance valve. Frequency Control Program SR 3.5.3.2 Verify each RCIC System manual, power In accordance with operated, and automatic valve in the flow path, the Surveillance that is not locked, sealed, or otherwise secured in Frequency Control position, is in the correct position. Program SR 3.5.3.3 ----------.--.---------- NOTE --.--..------.---------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure and flow are adequate to perform the test.

Verify, with reactor pressure < 1058 psig and In accordance with

> 920 psig, the RCIC pump can develop a flow the Surveillance rate > 400 gpm against a system head Frequency Control corresponding to reactor pressure. Program SR 3.5.3.4 --------....-------.---- NOTE --.--..------.---------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure and flow are adequate to perform the test.

Verify, with reactor pressure < 165 psig, the RCIC In accordance with pump can develop a flow rate > 400 gpm against a the Surveillance system head corresponding to reactor pressure. Frequency Control Program SR 3.5.3.5 ---- --.-.----------.-- NOTE --.....----..-----------

Vessel injection may be excluded.

Verify the RCIC System actuates on an actual or In accordance with simulated automatic initiation signal. the Surveillance Frequency Control

NOTE----.-.-------.-.-.-------- Program Not required to be met for system vent flow paths opened under administrative control.

HATCH UNIT 2 3.5-11 Amendment No. 240 to NL-14-1349 HNP Technical Specification Marked Up Pages RHR Suppression Pool Cooling 3.6.2.3 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.2.3. Verify each required RHR pump develops a flow In accordance with rate > 7700 gpm through the associated heat the Inservice exchanger while operating in the suppression pool Testing Program cooling mode.

SR 3.6.2.3.2 Verify RHR suppression pool cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 2 3.6-26 Amendment No. 4-35 to NL-14-1349 HNP Technical Specification Marked Up Pages RHR Suppression Pool Spray 3.6.2.4 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.2.4.2 Verify each suppression pool spray nozzle is In accordance with unobstructed. the Surveillance 3I Fý Frequency Control Program SR 3.6.2.4.2 Verify RHR suppression pool spray subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 2 3.6-28 Amendment No. 240 I to NL-14-1349 HNP Technical Specification Marked Up Pages RHR Drywell Spray 3.6.2.5 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY

+

SR Verify each drywell spray nozzle is unobstructed. Following maintenance

3. . which could result in nozzle blockage.

SR 3.6.2.5.2 Verify RHR drywell spray subsystem locations In accordance with susceptible to gas accumulation are sufficiently the Surveillance filled with water. Frequency Control Program HATCH UNIT 2 3.6-30 Amendment No. 200 1 to NL-14-1349 HNP Technical Specification Marked Up Pages RHR - High Water Level 3.9.7 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME B. (continued) B.3 Initiate action to restore Immediately required standby gas treatment subsystem(s) to OPERABLE status.

AND B.4 Initiate action to restore Immediately isolation capability in each required secondary containment penetration flow path not isolated.

C. No RHR shutdown cooling C.1 Verify reactor coolant 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery subsystem in operation. circulation by an of no reactor coolant alternate method. circulation AND Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter AND C.2 Monitor reactor coolant Once per hour temperature.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.9.7.1 Verify one RHR shutdown cooling subsystem is In accordance with operating. the Surveillance Frequency Control Program SR 3.9.7.2 Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 2 3.9-11 Amendment No. 240 to NL-14-1349 HNP Technical Specification Marked Up Pages RHR - Low Water Level 3.9.8 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME B. (continued) B.3 Initiate action to restore Immediately isolation capability in each required secondary containment penetration flow path not isolated.

C. No RHR shutdown cooling C.1 Verify reactor coolant 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery subsystem in operation. circulation by an of no reactor coolant alternate method. circulation AND Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter AND C.2 Monitor reactor coolant Once per hour temperature.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.9.8.1 Verify one RHR shutdown cooling subsystem is In accordance with operating. the Surveillance Frequency Control Program SR 3.9.8.2 Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 2 3.9-13 Amendment No. 240 1

Edwin I. Hatch Nuclear Plant License Amendment Request to Revise Technical Specifications GL 2008-01, Managing Gas Accumulation, Revision 2, Using the Consolidated Line Item Improvement Process (CLIIP)

Enclosure 3 HNP Technical Specification Clean Typed Pages

RHR Shutdown Cooling System - Hot Shutdown 3.4.7 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.7.1 -NOTE Not required to be met until 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months after reactor steam dome pressure is less than the RHR low pressure permissive pressure.

Verify one RHR shutdown cooling subsystem or In accordance with recirculation pump is operating. the Surveillance Frequency Control Program SR 3.4.7.2 -NOTE Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam dome pressure is less than the RHR low pressure permissive pressure.

Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 1 3.4-15 Amendment No.

RHR Shutdown Cooling System - Cold Shutdown 3.4.8 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME B. No RHR shutdown cooling B.1 Verify reactor coolant 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery subsystem in operation. circulation by an of no reactor coolant alternate method. circulation AND AND No recirculation pump in operation. Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter AND B.2 Monitor reactor coolant Once per hour temperature.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.8.1 Verify one RHR shutdown cooling subsystem or In accordance with recirculation pump is operating. the Surveillance Frequency Control Program SR 3.4.8.2 Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 1 3.4-17 Amendment No.

ECCS - Operating 3.5.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.1.1 Verify, for each ECCS injection/spray subsystem, In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program SR 3.5.1.2 --------------------- NOTES---------------

1. Low pressure coolant injection (LPCI) subsystems may be considered OPERABLE during alignment and operation for decay heat removal with reactor steam dome pressure less than the Residual Heat Removal (RHR) low pressure permissive pressure in MODE 3, ifcapable of being manually realigned and not otherwise inoperable.

2. Not required to be met for system vent flowpaths opened under administrative control.

Verify each ECCS injection/spray subsystem In accordance with manual, power operated, and automatic valve in the Surveillance the flow path, that is not locked, sealed, or Frequency Control otherwise secured in position, is in the correct Program position.

SR 3.5.1.3 Verify ADS air supply header pressure is In accordance with

_ 90 psig. the Surveillance Frequency Control Program SR 3.5.1.4 Verify the RHR System cross tie valve is closed In accordance with and power is removed from the valve operator. the Surveillance Frequency Control Program SR 3.5.1.5 (Not used.)

(continued)

HATCH UNIT 1 3.5-3 Amendment No.

ECCS - Shutdown 3.5.2 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.5.2.3 Verify, for each required ECCS injection/spray In accordance with subsystem, locations susceptible to gas the Surveillance accumulation are sufficiently filled with water. Frequency Control Program SR 3.5.2.4 --------------------- NOTES---------------

1. One LPCI subsystem may be considered OPERABLE during alignment and operation for decay heat removal if capable of being manually realigned and not otherwise inoperable.

2. Not required to be met for system vent flowpaths opened under administrative control.

Verify each required ECCS injection/spray In accordance with subsystem manual, power operated, and the Surveillance automatic valve in the flow path, that is not locked, Frequency Control sealed, or otherwise secured in position, is in the Program correct position.

SR 3.5.2.5 Verify each required ECCS pump develops the In accordance with specified flow rate against a system head the Inservice corresponding to the specified reactor pressure. Testing Program SYSTEM HEAD CORRESPONDING NO. OF TO A REACTOR SYSTEM FLOW RATE PUMPS PRESSURE OF CS > 4250 gpm 1 ! 113 psig LPCI > 7700 gpm 1 > 20 psig SR 3.5.2.6 -------------------- NOTE ----------------

Vessel injection/spray may be excluded.

Verify each required ECCS injection/spray In accordance with subsystem actuates on an actual or simulated the Surveillance automatic initiation signal. Frequency Control Program HATCH UNIT 1 3.5-8 Amendment No.

RCIC System 3.5.3 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.3.1 Verify the RCIC System locations susceptible to In accordance with gas accumulation are sufficiently filled with water. the Surveillance Frequency Control Program SR 3.5.3.2 --------------------- NOTE ----------------

Not required to be met for system vent flow paths opened under administrative control.

Verify each RCIC System manual, power In accordance with operated, and automatic valve in the flow path, the Surveillance that is not locked, sealed, or otherwise secured in Frequency Control position, is in the correct position. Program SR 3.5.3.3 --------------------- NOTE ----------------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure and flow are adequate to perform the test.

Verify, with reactor pressure < 1058 psig and In accordance with

> 920 psig, the RCIC pump can develop a flow the Surveillance rate > 400 gpm against a system head Frequency Control corresponding to reactor pressure. Program SR 3.5.3.4 --------------------- NOTE ----------------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure and flow are adequate to perform the test.

Verify, with reactor pressure < 165 psig, the RCIC In accordance with pump can develop a flow rate > 400 gpm against a the Surveillance system head corresponding to reactor pressure. Frequency Control Program SR 3.5.3.5 --------------------- NOTE ----------------

Vessel injection may be excluded.

Verify the RCIC System actuates on an actual or In accordance with simulated automatic initiation signal. the Surveillance Frequency Control Program HATCH UNIT 1 3.5-10 Amendment No.

RHR Suppression Pool Cooling 3.6.2.3 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.2.3.2 Verify RHR suppression pool cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program SR 3.6.2.3.3 Verify each required RHR pump develops a flow In accordance with rate > 7700 gpm through the associated heat the Inservice exchanger while operating in the suppression pool Testing Program cooling mode.

HATCH UNIT 1 3.6-26 Amendment No.

RHR Suppression Pool Spray 3.6.2.4 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.2.4.2 Verify RHR suppression pool spray subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program SR 3.6.2.4.3 Verify each suppression pool spray nozzle is In accordance with unobstructed. the Surveillance Frequency Control Program HATCH UNIT 1 3.6-28 Amendment No.

RHR Drywell Spray 3.6.2.5 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.2.5.2 Verify RHR drywell spray subsystem locations In accordance with susceptible to gas accumulation are sufficiently the Surveillance filled with water. Frequency Control Program SR 3.6.2.5.3 Verify each drywell spray nozzle is unobstructed. Following maintenance which could result in nozzle blockage.

HATCH UNIT 1 3.6-30 Amendment No.

RHR - High Water Level 3.9.7 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME B. (continued) B.3 Initiate action to restore Immediately required standby gas treatment subsystem(s) to OPERABLE status.

AND B.4 Initiate action to restore Immediately isolation capability in each required secondary containment penetration flow path not isolated.

C. No RHR shutdown cooling C.1 Verify reactor coolant 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery subsystem in operation. circulation by an of no reactor coolant alternate method. circulation AND Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter AND C.2 Monitor reactor coolant Once per hour temperature.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.9.7.1 Verify one RHR shutdown cooling subsystem is In accordance with operating. the Surveillance Frequency Control Program SR 3.9.7.2 Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 1 3.9-10 Amendment No.

RHR - Low Water Level 3.9.8 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME B. (continued) B.3 Initiate action to restore Immediately isolation capability in each required secondary containment penetration flow path not isolated.

C. No RHR shutdown cooling C.1 Verify reactor coolant 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery subsystem in operation. circulation by an of no reactor coolant alternate method. circulation AND Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter AND C.2 Monitor reactor coolant Once per hour temperature.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.9.8.1 Verify one RHR shutdown cooling subsystem is In accordance with operating. the Surveillance Frequency Control Program SR 3.9.8.2 Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 1 3.9-12 Amendment No.

RHR Shutdown Cooling System - Hot Shutdown 3.4.7 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.7.1 ------------------ NOTE ---------------

Not required to be met until 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months after reactor steam dome pressure is less than the RHR low pressure permissive pressure.

Verify one RHR shutdown cooling subsystem or In accordance with recirculation pump is operating. the Surveillance Frequency Control Program i

SR 3.4.7.2 ------------------ NOTE ---------------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam dome pressure is less than the RHR low pressure permissive pressure.

Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 2 3.4-15 Amendment No.

RHR Shutdown Cooling System - Cold Shutdown 3.4.8 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME B. No RHR shutdown cooling B.1 Verify reactor coolant 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery subsystem in operation. circulation by an of no reactor coolant alternate method. circulation AND AND No recirculation pump in operation. Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter AND B.2 Monitor reactor coolant Once per hour temperature.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.8.1 Verify one RHR shutdown cooling subsystem or In accordance with recirculation pump is operating. the Surveillance Frequency Control Program SR 3.4.8.2 Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 2 3.4-17 Amendment No.

ECCS - Operating 3.5.1 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.1.1 Verify, for each ECCS injection/spray subsystem, In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program SR 3.5.1.2 --------------------- NOTES---------------

1. Low pressure coolant injection (LPCI) subsystems may be considered OPERABLE during alignment and operation for decay heat removal with reactor steam dome pressure less than the Residual Heat Removal (RHR) low pressure permissive pressure in MODE 3, if capable of being manually realigned and not otherwise inoperable.

2. Not required to be met for system vent flowpaths opened under administrative control.

Verify each ECCS injection/spray subsystem In accordance with manual, power operated, and automatic valve in the Surveillance the flow path, that is not locked, sealed, or Frequency Control otherwise secured in position, is in the correct Program position.

SR 3.5.1.3 Verify ADS air supply header pressure is In accordance with

> 90 psig. the Surveillance Frequency Control Program SR 3.5.1.4 Verify the RHR System cross tie valve is closed In accordance with and power is removed from the valve operator. the Surveillance Frequency Control Program SR 3.5.1.5 (Not used.)

(continued)

HATCH UNIT 2 3.5-3 Amendment No.

ECCS - Shutdown 3.5.2 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.5.2.3 Verify, for each required ECCS injection/spray In accordance with subsystem, locations susceptible to gas the Surveillance accumulation are sufficiently filled with water. Frequency Control Program SR 3.5.2.4 -------------------- NOTES ----------------

1. One LPCI subsystem may be considered OPERABLE during alignment and operation for decay heat removal if capable of being manually realigned and not otherwise inoperable.

2. Not required to be met for system vent flowpaths opened under administrative control.

Verify each required ECCS injection/spray In accordance with subsystem manual, power operated, and the Surveillance automatic valve in the flow path, that is not locked, Frequency Control sealed, or otherwise secured in position, is in the Program correct position.

SR 3.5.2.5 Verify each required ECCS pump develops the In accordance with specified flow rate against a system head the Inservice corresponding to the specified reactor pressure. Testing Program SYSTEM HEAD CORRESPONDING NO. OF TO A REACTOR SYSTEM FLOW RATE PUMPS PRESSURE OF CS > 4250 gpm 1 > 113 psig LPCI > 7700 gpm 1 > 20 psig SR 3.5.2.6 -------------------- NOTE ----------------

Vessel injection/spray may be excluded.

Verify each required ECCS injection/spray In accordance with subsystem actuates on an actual or simulated the Surveillance automatic initiation signal. Frequency Control Program HATCH UNIT 2 3.5-9 Amendment No.

RCIC System 3.5.3 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.3.1 Verify the RCIC System locations susceptible to In accordance with gas accumulation are sufficiently filled with water. the Surveillance Frequency Control Program SR 3.5.3.2 --------------------- NOTE ---------------

Not required to be met for system vent flow paths opened under administrative control.

Verify each RCIC System manual, power In accordance with operated, and automatic valve in the flow path, the Surveillance that is not locked, sealed, or otherwise secured in Frequency Control position, is in the correct position. Program SR 3.5.3.3 --------------------- NOTE ---------------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure and flow are adequate to perform the test.

Verify, with reactor pressure < 1058 psig and In accordance with

> 920 psig, the RCIC pump can develop a flow the Surveillance rate > 400 gpm against a system head Frequency Control corresponding to reactor pressure. Program SR 3.5.3.4 --------------------- NOTE - ----------------

Not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure and flow are adequate to perform the test.

Verify, with reactor pressure < 165 psig, the RCIC In accordance with pump can develop a flow rate > 400 gpm against a the Surveillance system head corresponding to reactor pressure. Frequency Control Program SR 3.5.3.5 --------------------- NOTE ---------------

Vessel injection may be excluded.

Verify the RCIC System actuates on an actual or In accordance with simulated automatic initiation signal. the Surveillance Frequency Control Program HATCH UNIT 2 3.5-11 Amendment No.

RHR Suppression Pool Cooling 3.6.2.3 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.2.3.2 Verify RHR suppression pool cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program SR 3.6.2.3.3 Verify each required RHR pump develops a flow In accordance with rate > 7700 gpm through the associated heat the Inservice exchanger while operating in the suppression pool Testing Program cooling mode.

HATCH UNIT 2 3.6-26 Amendment No.

RHR Suppression Pool Spray 3.6.2.4 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.2.4.2 Verify RHR suppression pool spray subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program SR 3.6.2.4.3 Verify each suppression pool spray nozzle is In accordance with unobstructed. the Surveillance Frequency Control Program HATCH UNIT 2 3.6-28 Amendment No.

RHR Drywell Spray 3.6.2.5 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.6.2.5.2 Verify RHR drywell spray subsystem locations In accordance with susceptible to gas accumulation are sufficiently the Surveillance filled with water. Frequency Control Program SR 3.6.2.5.3 Verify each drywell spray nozzle is unobstructed. Following maintenance which could result in nozzle blockage HATCH UNIT 2 3.6-30 Amendment No.

RHR - High Water Level 3.9.7 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME B. (continued) B.3 Initiate action to restore Immediately required standby gas treatment subsystem(s) to OPERABLE status.

AND B.4 Initiate action to restore Immediately isolation capability in each required secondary containment penetration flow path not isolated.

C. No RHR shutdown cooling C.1 Verify reactor coolant 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery subsystem in operation. circulation by an of no reactor coolant alternate method. circulation AND Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter AND C.2 Monitor reactor coolant Once per hour temperature.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.9.7.1 Verify one RHR shutdown cooling subsystem is In accordance with operating. the Surveillance Frequency Control Program SR 3.9.7.2 Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 2 3.9-11 Amendment No.

RHR - Low Water Level 3.9.8 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME B. (continued) B.3 Initiate action to restore Immediately isolation capability in each required secondary containment penetration flow path not isolated.

C. No RHR shutdown cooling C.1 Verify reactor coolant 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months from discovery subsystem in operation. circulation by an of no reactor coolant alternate method. circulation AND Once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter AND C.2 Monitor reactor coolant Once per hour temperature.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.9.8.1 Verify one RHR shutdown cooling subsystem is In accordance with operating. the Surveillance Frequency Control Program SR 3.9.8.2 Verify required RHR shutdown cooling subsystem In accordance with locations susceptible to gas accumulation are the Surveillance sufficiently filled with water. Frequency Control Program HATCH UNIT 2 3.9-13 Amendment No.

Edwin I. Hatch Nuclear Plant License Amendment Request to Revise Technical Specifications GL 2008-01, Managing Gas Accumulation, Revision 2, Using the Consolidated Line Item Improvement Process (CLIIP)

Enclosure 4 HNP Technical Specification Bases Marked Up Pages (for information only) to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR Shutdown Cooling System - Hot Shutdown B 3.4.7 BASES LCO decreased to < 212°F within the time limit specified in Regulatory (continued) Guide 1.139, "Guidance for Residual Heat Removal," assuming two RHRSW System pumps are in operation. OPERABILITY requirements for the RHRSW System in Mode 3 are addressed by LCO 3.7.1, "Residual Heat Removal Service Water (RHRSW)

System."

The two required RHR shutdown cooling subsystems have a common suction source and are allowed to have a common heat exchanger and common discharge piping. Since the piping and heat exchangers are passive components that are assumed not to fail, they are allowed to be common to both required subsystems. Thus, to meet the LCO, both RHR pumps in one loop or one RHR pump in each of the two loops must be OPERABLE. If the two required subsystems consist of an RHR pump in each loop, both heat exchangers, each with two OPERABLE RHRSW System pumps supplying cooling water, are required since one heat exchanger will not be common to both subsystems. Each shutdown cooling subsystem is considered OPERABLE if it can be manually aligned (remote or local) in the shutdown cooling mode for removal of decay heat. In MODE 3, one RHR shutdown cooling subsystem can provide the required cooling (sufficient to reduce and maintain reactor coolant temperature

< 212 0 F), but two subsystems are required to be OPERABLE to provide redundancy. Operation of one subsystem can maintain or reduce the reactor coolant temperature as required. However, to ensure adequate core flow to allow for accurate average reactor coolant temperature monitoring, nearly continuous operation is required. Management of gas voids is important to RHR Shutdown Cooling System OPERABILITY. In MODE 3, the RHR cross tie valve (1El 1-FO10) may not be opened (per LCO 3.5.1) to allow pumps in one loop to discharge through the opposite recirculation loop.

Note 1 permits both RHR shutdown cooling subsystems and recirculation pumps to be shut down for a period of 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months in an 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months period. Note 2 allows one RHR shutdown cooling subsystem to be inoperable for up to 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months for performance of Surveillance tests. These tests may be on the affected RHR System or on some other plant system or component that necessitates placing the RHR System in an inoperable status during the performance. This is permitted because the core heat generation can be low enough and the heatup rate slow enough to allow some changes to the RHR subsystems or other operations requiring RHR flow interruption and loss of redundancy.

The LCO consists of two separate requirements. Either requirement can be not met (and the associated Condition entered) without necessarily affecting the other (and without necessarily entering the (continued)

HATCH UNIT 1 B 3.4-29 REVISION 4-5 to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR Shutdown Cooling System - Hot Shutdown B 3.4.7 BASES SURVEILLANCE SR 3.4.7.1 (continued)

REQUIREMENTS This Surveillance is modified by a Note allowing sufficient time to align the RHR System for shutdown cooling operation after clearing the pressure interlock that isolates the system, or for placing a recirculation pump in operation. The Note takes exception to the requirements of the Surveillance being met (i.e., forced coolant circulation is not required for this initial 2 hour2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months period), which also allows entry into the Applicability of this Specification in accordance with SR 3.0.4 since the Surveillance will not be "not met" at the time of entry into the Applicability.

SR 3.4.7.2 RHR Shutdown Cooling System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR shutdown cooling subsystems and may also prevent water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel.

Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The RHR Shutdown Cooling System is OPERABLE when it is sufficiently filled with water. For the RHR SDC piping on the discharge side of the RHR pump, acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume in the RHR SDC piping on the discharge side of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water),

the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits. Since the RHR SDC piping on the discharge side of the pump is the same as (continued)

HATCH UNIT 1 B 3.4-33 REVISION 4.9 1 to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR Shutdown Cooling System - Hot Shutdown B 3.4.7 BASES SURVEILLANCE SR 3.4.7.2 (continued)

REQUIREMENTS the Low Pressure Coolant Injection piping, performances of surveillances for ECCS TS may satisfy the requirements of this surveillance. For the RHR SDC piping on the suction side of the RHR pump, the surveillance is met by virtue of the performance of operating procedures that ensure that the RHR SDC suction piping is adequately filled and vented. The performance of these manual actions ensures that the surveillance is met.

RHR SDC System locations on the discharqe side of the RHR pump susceptible to gas accumulation are monitored and, ifgas is found, the gas volume is compared to the acceptance criteria for the location.

Susceptible locations in the same system flow path which are subiect to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety.

For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location.

Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The SR may be met for one RHR SDC subsystem by virtue of having a subsystem in service in accordance with operating procedures.

This SR is modified by a Note that states the SR is not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam dome pressure is less than the RHR low pressure permissive pressure. In a rapid shutdown, there may be insufficient time to verify all susceptible locations prior to entering the Applicability.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

REFERENCES 1. NRC No.93-102, "Final Policy Statement on Technical Specification Improvements," July 23, 1993.

HATCH UNIT 1 B3.4-34 REVISION 49 1 to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR Shutdown Cooling System - Cold Shutdown B 3.4.8 BASES LCO loops must be OPERABLE. If the two required subsystems consist of (continued) an RHR pump in each loop, both heat exchangers are required since one heat exchanger will not be common to both subsystems. In MODE 4, the RHR cross tie valve (1El1-FO10) may be opened (per LCO 3.5.2) to allow pumps in one loop to discharge through the opposite recirculation loop to make a complete subsystem.

Similarly, to meet the LCO, the cooling supply for the heat exchanger(s) requires two RHRSW pumps (either one pump in each RHRSW loop or two pumps in one RHRSW loop). With one RHR heat exchanger common to both RHR shutdown cooling subsystems, each RHRSW pump is required to be capable of providing cooling to that heat exchanger (Note: the RHRSW cross tie valves may be open to allow the RHRSW pump(s) in one loop to provide cooling to a heat exchanger in the opposite loop to make a complete subsystem.), or with both heat exchangers required, each heat exchanger is required to have an RHRSW pump capable of providing coolant to that heat exchanger.

Additionally, each shutdown cooling subsystem is considered OPERABLE if it can be manually aligned (remote or local) in the shutdown cooling mode for removal of decay heat. In MODE 4, one RHR shutdown cooling subsystem can provide the required cooling (sufficient to maintain reactor coolant temperature < 212 0 F), but two subsystems are required to be OPERABLE to provide redundancy.

Operation of one subsystem can maintain or reduce the reactor coolant temperature as required. However, to ensure adequate core flow to allow for accurate average reactor coolant temperature monitoring, nearly continuous operation is required. Management of gas voids is important to RHR Shutdown Cooling System OPERABILITY.

Note 1 permits both RHR shutdown cooling subsystems and recirculation pumps to be shut down for a period of 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months in an 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months period. Note 2 allows one RHR shutdown cooling subsystem to be inoperable for up to 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months for performance of Surveillance tests. These tests may be on the affected RHR System or on some other plant system or component that necessitates placing the RHR System in an inoperable status during the performance. This is permitted because the core heat generation can be low enough and the heatup rate slow enough to allow some changes to the RHR subsystems or other operations requiring RHR flow interruption and loss of redundancy.

The LCO consists of two separate requirements. Either requirement can be not met (and the associated Condition entered) without necessarily affecting the other (and without necessarily entering the (continued)

HATCH UNIT 1 B 3.4-35 REVISION 4- ý to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR Shutdown Cooling System - Cold Shutdown B 3.4.8 BASES ACTIONS B.1 and B.2 (continued) function and is modified such that the 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months is applicable separately for each occurrence involving a loss of coolant circulation.

Furthermore, verification of the functioning of the alternate method must be reconfirmed every 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter. This will provide assurance of continued temperature monitoring capability.

During the period when the reactor coolant is being circulated by an alternate method (other than by the required RHR shutdown cooling subsystem or recirculation pump), the reactor coolant temperature and pressure must be periodically monitored to ensure proper function of the alternate method. The once per hour Completion Time is deemed appropriate.

SURVEILLANCE SR 3.4.8.1 REQUIREMENTS This Surveillance verifies that one RHR shutdown cooling subsystem or recirculation pump is in operation and circulating reactor coolant.

The required flow rate is determined by the flow rate necessary to provide sufficient decay heat removal capability. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

SR 3.4.8.2 RHR Shutdown Cooling System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR shutdown cooling subsystems and may also prevent water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel.

Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

(continued)

HATCH UNIT 1 B 3.4-38 REVISION 6Q I to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR Shutdown Cooling System - Cold Shutdown B 3.4.8 BASES SURVEILLANCE SR 3.4.8.2 (continued)

REQUIREMENTS The RHR Shutdown Cooling System is OPERABLE when it is sufficiently filled with water. For the RHR SDC piping on the discharge side of the RHR pump, acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume in the RHR SDC piping on the discharge side of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water),

the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits. Since the RHR SDC piping on the discharge side of the pump is the same as the Low Pressure Coolant Injection piping, performances of surveillances for ECCS TS may satisfy the requirements of this surveillance. For the RHR SDC piping on the suction side of the RHR pump, the surveillance is met by virtue of the performance of operating procedures that ensure that the RHR SDC suction piping is adequately filled and vented. The performance of these manual actions ensures that the surveillance is met.

RHR SDC System locations on the discharge side of the RHR pump susceptible to gas accumulation are monitored and, ifgas is found, the gas volume is compared to the acceptance criteria for the location.

Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety.

For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location.

Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The SR may be met for one RHR SDC subsystem by virtue of having a subsystem in service in accordance with operating procedures.

(continued)

HATCH UNIT 1 B 3.4-39 REVISION 69 1 to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR Shutdown Cooling System - Cold Shutdown B 3.4.8 BASES SURVEILLANCE SR 3.4.8.2 (continued)

REQUIREMENTS The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

REFERENCES 1. NRC No.93-102, "Final Policy Statement on Technical Specification Improvements," July 23, 1993.

HATCH UNIT 1 B 3.4-40 REVISION &9 1 to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

ECCS - Operating B 3.5.1 BASES (continued)

APPLICABLE The ECCS performance is evaluated for the entire spectrum of SAFETY ANALYSES break sizes for a postulated LOCA. The accidents for which ECCS operation is required are presented in References 5 and 6. The required analyses and assumptions are defined in Reference 7. The results of these analyses are also described in References 8 and 9.

This LCO helps to ensure that the following acceptance criteria for the ECCS, established by 10 CFR 50.46 (Ref. 10), will be met following a LOCA, assuming the worst case single active component failure in the ECCS:

a. Maximum fuel element cladding temperature is < 2200°F;

b. Maximum cladding oxidation is < 0.17 times the total cladding thickness before oxidation;

c. Maximum hydrogen generation from a zirconium water reaction is < 0.01 times the hypothetical amount that would be generated if all of the metal in the cladding surrounding the fuel, excluding the cladding surrounding the plenum volume, were to react;

d. The core is maintained in a coolable geometry; and e.

Adequate long term cooling capability is maintained.

The limiting single failures are discussed in Reference 9. The remaining OPERABLE ECCS subsystems provide the capability to adequately cool the core and prevent excessive fuel damage.

The ECCS satisfy Criteria 3 and 4 of the NRC Policy Statement (Ref. 12).

LCO Each ECCS injection/spray subsystem and six of seven ADS valves are required to be OPERABLE. The ECCS injection/spray subsystems are defined as the two CS subsystems, the two LPCI subsystems, and one HPCI System. The low pressure ECCS injection/spray subsystems are defined as the two CS subsystems and the two LPCI subsystems. Management of gas voids is important to ECCS inhection/spray subsystem OPERABILITY.

With less than the required number of ECCS subsystems OPERABLE, the potential exists that during a limiting design basis LOCA concurrent with the worst case single failure, the limits specified in Reference 10 could be exceeded. All low pressure ECCS (continued)

HATCH UNIT 1 B 3.5-4 REVISION 4-3 1 to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

ECCS - Operating B 3.5.1 BASES (continued)

SURVEILLANCE SR 3.5.1.1 REQUIREMENTS The ECCS injection/spray subsystem flow path piping and components

as have the potential to develop voids and pockets of entrained aifgases. Maintaining the pump discharge lines of the HPCI System;-,

CS System, and LPC! subsystems full of .ter ensures that the--ES YAWperform properly, injecting its full capacity into the RCS upone depmaa;d. This-wM4- alse Preventing and managing gas intrusion and accumulation is necessary for proper operation of the ECCS injection/spray subsystems and may also prevent a water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel, following an ECCS initiati*

n ignal. One ac.eptable mriethod of ensuring that the lines a.e full is to*.nt at the high pint. In addition, when HPCI is aligned to the suppression pool (instead of the CST), one acceptable method is to monitor pump suction pressure.

Selection of ECCS iniection/spray subsystem locations susceptible to gas accumulation is based on a review of system design information including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations.

The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The ECCS iniection/spray subsystem is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the ECCS iniection/spray subsystems are not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.

ECCS iniection/spray subsystem locations susceptible to gas accumulation are monitored and, ifgas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a (continued)

HATCH UNIT 1 B 3.5-8 REVISION 69 ý to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

ECCS - Operating B 3.5.1 BASES SURVEILLANCE SR 3.5.1.1 (continued)

REQUIREMENTS representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety.

For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location.

Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to ,as accumulation.

SR 3.5.1.2 Verifying the correct alignment for manual, power operated, and automatic valves in the ECCS flow paths provides assurance that the proper flow paths will exist for ECCS operation. This SR does not apply to valves that are locked, sealed, or otherwise secured in position since these were verified to be in the correct position prior to locking, sealing, or securing. A valve that receives an initiation signal is allowed to be in a nonaccident position provided the valve will automatically reposition in the proper stroke time. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of potentially being mispositioned are in the correct position. This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.

For the HPCI System, this SR also includes the steam flow path for the turbine and the flow controller position.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

This SR is modified by a Note 1 that allows LPCI subsystems to be considered OPERABLE during alignment and operation for decay heat removal with reactor steam dome pressure less than the RHR low pressure permissive pressure in MODE 3, if capable of being manually realigned (remote or local) to the LPCI mode and not otherwise inoperable. This allows operation in the RHR shutdown cooling mode during MODE 3, if necessary.

(continued)

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ECCS - Operating B 3.5.1 BASES SURVEILLANCE SR 3.5.1.2 (continued)

REQUIREMENTS The Surveillance is also modified by a Note 2 which exempts system vent flow paths opened under administrative control. The administrative control should be proceduralized and include stationing a dedicated individual who can rapidly close the system vent flow path if directed.

SR 3.5.1.3 Verification that ADS air supply header pressure is > 90 psig ensures adequate air pressure for reliable ADS operation. The accumulator on each ADS valve provides pneumatic pressure for valve actuation.

The design pneumatic supply pressure requirements for the accumulator are such that, following a failure of the pneumatic supply to the accumulator, at least two valve actuations can occur with the drywell at 70% of design pressure (Ref. 11). The ECCS safety analysis assumes only one actuation to achieve the depressurization required for operation of the low pressure ECCS. This minimum required pressure of > 90 psig (for one actuation) is provided by the ADS instrument air supply. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

SR 3.5.1.4 Verification that the RHR System cross tie valve is closed and power to its operator is disconnected ensures that each LPCI subsystem remains independent and a failure of the flow path in one subsystem will not affect the flow path of the other LPCI subsystem. Acceptable methods of removing power to the operator include de-energizing breaker control power or racking out or removing the breaker. If the RHR System cross tie valve is open or power has not been removed from the valve operator, both LPCI subsystems must be considered inoperable. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

SR 3.5.1.5 (Not used.)

SR 3.5.1.6 Cycling the recirculation pump discharge valves through one complete cycle of full travel demonstrates that the valves are mechanically OPERABLE and will close when required. Upon initiation of an automatic LPCI subsystem injection signal, these valves are required (continued)

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ECCS - Shutdown B 3.5.2 B 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) AND REACTOR CORE ISOLATION COOLING (RCIC) SYSTEM B 3.5.2 ECCS - Shutdown BASES BACKGROUND A description of the Core Spray (CS) System and the low pressure coolant injection (LPCI) mode of the Residual Heat Removal (RHR)

System is provided in the Bases for LCO 3.5.1, "ECCS - Operating."

APPLICABLE The ECCS performance is evaluated for the entire spectrum of SAFETY ANALYSES break sizes for a postulated loss of coolant accident (LOCA). The long term cooling analysis following a design basis LOCA (Ref. 1) demonstrates that only one low pressure ECCS injection/spray subsystem is required, post LOCA, to maintain adequate reactor vessel water level in the event of an inadvertent vessel draindown. It is reasonable to assume, based on engineering judgment, that while in MODES 4 and 5, one low pressure ECCS injection/spray subsystem can maintain adequate reactor vessel water level. To provide redundancy, a minimum of two low pressure ECCS injection/spray subsystems are required to be OPERABLE in MODES 4 and 5.

The low pressure ECCS subsystems satisfy Criterion 3 of the NRC Policy Statement (Ref. 3).

LCO Two low pressure ECCS injection/spray subsystems are required to be OPERABLE. The low pressure ECCS injection/spray subsystems consist of two CS subsystems and two LPCI subsystems. Each CS subsystem consists of one motor driven pump, piping, and valves to transfer water from the suppression pool or condensate storage tank (CST) to the reactor pressure vessel (RPV). Each LPCI subsystem consists of one motor driven pump, piping, and valves to transfer water from the suppression pool to the RPV. Only a single LPCI pump is required per subsystem because of the larger injection capacity in relation to a CS subsystem. In MODES 4 and 5, the RHR System cross tie valve is not required to be closed. Management of gas voids is important to ECCS iniection/spray subsystem OPERABILITY. The necessary portions of the Plant Service Water System are also required to provide appropriate cooling to each required ECCS subsystem.

(continued)

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ECCS - Shutdown B 3.5.2 BASES SURVEILLANCE SR 3.5.2.3, SR 3.5.2.5, and SR 3.5.2.6 REQUIREMENTS (continued) The Bases provided for SR 3.5.1.1, SR 3.5.1.7, and SR 3.5.1.10 are applicable to SR 3.5.2.3, SR 3.5.2.5, and SR 3.5.2.6, respectively.

However, the LPCI flow rate requirement for SR 3.5.2.5 is based on a single pump, not the two pump flow rate requirement of SR 3.5.1.7.

SR 3.5.2.4 Verifying the correct alignment for manual, power operated, and automatic valves in the ECCS flow paths provides assurance that the proper flow paths will exist for ECCS operation. This SR does not apply to valves that are locked, sealed, or otherwise secured in position, since these valves were verified to be in the correct position prior to locking, sealing, or securing. A valve that receives an initiation signal is allowed to be in a nonaccident position provided the valve will automatically reposition in the proper stroke time. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of potentially being mispositioned are in the correct position. This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

In MODES 4 and 5, the RHR System may operate in the shutdown cooling mode to remove decay heat and sensible heat from the reactor. Therefore, RHR valves that are required for LPCI subsystem operation may be aligned for decay heat removal. Therefore, this SR is modified by a Note 1 that allows one LPCI subsystem of the RHR System to be considered OPERABLE for the ECCS function if all the required valves in the LPCI flow path can be manually realigned (remote or local) to allow injection into the RPV, and the system is not otherwise inoperable. This will ensure adequate core cooling if an inadvertent RPV draindown should occur.

The Surveillance is also modified by a Note 2 which exempts system vent flow paths opened under administrative control. The administrative control should be proceduralized and include stationing a dedicated individual who can rapidly close the system vent flow path if directed.

(continued)

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RCIC System B 3.5.3 BASES BACKGROUND when other discharge line valves are closed. To ensure rapid delivery (continued) of water to the RPV and to minimize water hammer effects, the RCIC System discharge piping is kept full of water. The RCIC System is normally aligned to the CST. The height of water in the CST is sufficient to maintain the piping full of water up to the first isolation valve. The relative height of the feedwater line connection for RCIC is such that the water in the feedwater lines keeps the remaining portion of the RCIC discharge line full of water. Therefore, RCIC does not require a "keep fill" system.

APPLICABLE The function of the RCIC System is to respond to transient events by SAFETY ANALYSES providing makeup coolant to the reactor. The RCIC System is not an Engineered Safety Feature System and no credit is taken in the safety analyses for RCIC System operation. Based on its contribution to the reduction of overall plant risk, however, the system satisfies Criterion 4 of the NRC Policy Statement (Ref. 5).

LCO The OPERABILITY of the RCIC System provides adequate core cooling such that actuation of any of the low pressure ECCS subsystems is not required in the event of RPV isolation accompanied by a loss of feedwater flow. The RCIC System has sufficient capacity for maintaining RPV inventory during an isolation event. Management of gas voids is important to RCIC System OPERABILITY.

APPLICABILITY The RCIC System is required to be OPERABLE during MODE 1, and MODES 2 and 3 with reactor steam dome pressure > 150 psig, since RCIC is the primary non-ECCS water source for core cooling when the reactor is isolated and pressurized. In MODES 2 and 3 with reactor steam dome pressure < 150 psig, and in MODES 4 and 5, RCIC is not required to be OPERABLE since the low pressure ECCS injection/spray subsystems can provide sufficient flow to the RPV.

ACTIONS A Note prohibits the application of LCO 3.0.4.b to an inoperable RCIC subsystem. There is an increased risk associated with entering a MODE or other specified condition in the Applicability with an inoperable RCIC subsystem and the provisions of LCO 3.0.4.b, which allows entry into a MODE or other specified condition in the Applicability with the LCO not met after performance of a risk assessment addressing inoperable systems and components, should not be applied in this circumstance.

(continued)

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RCIC System B 3.5.3 BASES (continued)

SURVEILLANCE SR 3.5.3.1 REQUIREMENTS The RCIC System flow path piping and components have ha6-the potential to develop voids and pockets of entrained airgases.

MaintainiWng the pump discharge lfine of the RCIC Systemn full of waOter ensures thtte ?ytm will pe~foer properly, inftn it ull capacityf Rto* the React--r Coo,"lant System upon demand. ," This ,ll also rovn.

a water hammrr follyo'ng an initiation signal. Preventinq and managing gas intrusion and accumulation is necessary for proper operation of the RCIC System and may also prevent a water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel. One acceptable method of ensuring the line is full when aligned to the CST is"to Yent at the high points and, ';en aligned to the suppression pool,_is by monitoring pump suction pressure.

Selection of RCIC System locations susceptible to gas accumulation is based on a self-assessment of the piping confiuration to identify where gases may accumulate and remain even after the system is filled and vented, and to identify vulnerable potential degassing flow paths. The review is supplemented by verification that installed high-point vents are actually at the system high points, including field verification to ensure pipe shapes and construction tolerances have not inadvertently created additional high points. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The RCIC System is OPERABLE when it is sufficiently filled with water.

Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RCIC Systems are not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.

RCIC System locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subiect to the same gas intrusion mechanisms may be verified by monitoring a representative sub-set of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety. For these locations alternative (continued)

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RCIC System B 3.5.3 BASES SURVEILLANCE SR 3.5.3.1 (continued)

REQUIREMENTS methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location. Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenqge system OPERABILITY. The accuracy of the method used for monitorinq the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The Surveillance Frequency is controlled under the surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

SR 3.5.3.2 Verifying the correct alignment for manual, power operated, and automatic valves in the RCIC flow path provides assurance that the proper flow path will exist for RCIC operation. This SR does not apply to valves that are locked, sealed, or otherwise secured in position since these valves were verified to be in the correct position prior to locking, sealing, or securing. A valve that receives an initiation signal is allowed to be in a nonaccident position provided the valve will automatically reposition in the proper stroke time. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of potentially being mispositioned are in the correct position. This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.

For the RCIC System, this SR also includes the steam flow path for the turbine and the flow controller position.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

The Surveillance is modified by a Note which exempts system vent flow paths opened under administrative control. The administrative control should be proceduralized and include stationing a dedicated individual who can rapidly close the system vent flow path if directed.

SR 3.5.3.3 and SR 3.5.3.4 The RCIC pump flow rates ensure that the system can maintain reactor coolant inventory during pressurized conditions with the RPV isolated. The required flow rate (400 gpm) is the pump design flow (continued)

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RHR Suppression Pool Cooling B 3.6.2.3 BASES (continued)

LCO During a DBA, a minimum of one RHR suppression pool cooling subsystem is required to maintain the primary containment peak pressure and temperature below design limits (Ref. 1). To ensure that these requirements are met, two RHR suppression pool cooling subsystems must be OPERABLE with power from two safety related independent power supplies. Therefore, in the event of an accident, at least one subsystem is OPERABLE assuming the worst case single active failure. An RHR suppression pool cooling subsystem is OPERABLE when one of the pumps, the heat exchanger, and associated piping, valves, instrumentation, and controls are OPERABLE. Management of gas voids is important to RHR Suppression Pool Cooling System OPERABILITY. Each RHR suppression pool cooling subsystem is supported by an independent subsystem of the Residual Heat Removal Service Water (RHRSW)

System. Specifically, two OPERABLE RHRSW pumps and an OPERABLE flow path, as defined in the Bases for LCO 3.7.1, "Residual Heat Removal Service Water (RHRSW) System," are required to provide the necessary heat transfer from the heat exchanger and, thereby, support each suppression pool cooling subsystem.

APPLICABILITY In MODES 1, 2, and 3, a DBA could cause a release of radioactive material to primary containment and cause a heatup and pressurization of primary containment. In MODES 4 and 5, the probability and consequences of these events are reduced due to the pressure and temperature limitations in these MODES. Therefore, the RHR Suppression Pool Cooling System is not required to be OPERABLE in MODE 4 or 5.

ACTIONS A. 1 With one RHR suppression pool cooling subsystem inoperable, the inoperable subsystem must be restored to OPERABLE status within 7 days. In this Condition, the remaining RHR suppression pool cooling subsystem is adequate to perform the primary containment cooling function. However, the overall reliability is reduced because a single failure in the OPERABLE subsystem could result in reduced primary containment cooling capability. The 7 day Completion Time is acceptable in light of the redundant RHR suppression pool cooling capabilities afforded by the OPERABLE subsystem and the low probability of a DBA occurring during this period.

(continued)

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RHR Suppression Pool Cooling B 3.6.2.3 BASES SURVEILLANCE SR 3.6.2.3.2 REQUIREMENTS RHR Suppression Pool Cooling System piping and components have the potential to develop voids and pockets of entrained gases.

Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR suppression pool cooling subsystems and may also prevent water hammer and pump cavitation.

Selection of RHR Suppression Pool Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The RHR Suppression Pool Cooling System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Suppression Pool Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.

RHR Suppression Pool Cooling System locations susceptible to gas accumulation are monitored and, ifgas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety.

For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location.

Monitoring is not req uired for susceptible locations where the maximum potential accumulated gas void volume has been evaluated (continued)

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RHR Suppression Pool Cooling B 3.6.2.3 BASES SURVEILLANCE SR 3.6.2.3.2 (continued)

REQUIREMENTS and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

SR 3.6.2.3.3 Verifying that each required RHR pump develops a flow rate

> 7700 gpm while operating in the suppression pool cooling mode with flow through the associated heat exchanger ensures that pump performance has not degraded during the cycle. Flow is a normal test of centrifugal pump performance required by ASME Code, Section Xl (Ref. 2). This test confirms one point on the pump design curve, and the results are indicative of overall performance. Such inservice tests confirm component OPERABILITY and detect incipient failures by indicating abnormal performance. The Frequency of this SR is in accordance with the Inservice Testing Program.

REFERENCES 1. FSAR, Sections 5.2 and 14.4.3.

2. ASME, Boiler and Pressure Vessel Code,Section XI.

3. NRC No.93-102, "Final Policy Statement on Technical Specification Improvements," July 23, 1993.

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RHR Suppression Pool Spray B 3.6.2.4 BASES APPLICABLE containment conditions within design limits. The time history for SAFETY ANALYSES primary containment pressure is calculated to demonstrate that the (continued) maximum pressure remains below the design limit.

The RHR Suppression Pool Spray System satisfies Criterion 3 of the NRC Policy Statement (Ref. 2).

LCO In the event of a DBA, a minimum of one RHR suppression pool spray subsystem is required to mitigate potential bypass leakage paths and maintain the primary containment peak pressure below the design limits (Ref. 1). To ensure that these requirements are met, two RHR suppression pool spray subsystems must be OPERABLE with power from two safety related independent power supplies. Therefore, in the event of an accident, at least one subsystem is OPERABLE assuming the worst case single active failure. An RHR suppression pool spray subsystem is OPERABLE when one of the pumps, the heat exchanger, and associated piping, valves, instrumentation, and controls are OPERABLE. Management of gas voids is important to RHR Suppression Pool Spray System OPERABILITY. Each RHR suppression pool spray subsystem is supported by an independent subsystem of the Residual Heat Removal Service Water (RHRSW) System. Specifically, two OPERABLE RHRSW pumps and an OPERABLE flow path, as defined in the Bases for LCO 3.7.1, "Residual Heat Removal Service Water (RHRSW)

System," are required to provide the necessary heat transfer from the heat exchanger and, thereby, support each suppression pool spray subsystem.

APPLICABILITY In MODES 1, 2, and 3, a DBA could cause pressurization of primary containment. In MODES 4 and 5, the probability and consequences of these events are reduced due to the pressure and temperature limitations in these MODES. Therefore, maintaining RHR suppression pool spray subsystems OPERABLE is not required in MODE 4 or 5.

ACTIONS A.1 With one RHR suppression pool spray subsystem inoperable, the inoperable subsystem must be restored to OPERABLE status within 7 days. In this Condition, the remaining OPERABLE RHR (continued)

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RHR Suppression Pool Spray B 3.6.2.4 BASES SURVEILLANCE SR 3.6.2.4.1 (continued)

REQUIREMENTS A valve is also allowed to be in the nonaccident position provided it can be aligned to the accident position within the time assumed in the accident analysis. This is acceptable since the RHR suppression pool cooling mode is manually initiated. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of being mispositioned are in the correct position. This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.

The Surveillance Fequency is controlled under the Surveillance Frequency Control Program.

SR 3.6.2.4.2 RHR Suppression Pool Spray System piping and components have the potential to develop voids and pockets of entrained gases.

Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR suppression pool spray subsystems and may also prevent water hammer and pump cavitation.

Selection of RHR Suppression Pool Spray System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations.

The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The RHR Suppression Pool Spray System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Suppression Pool Spray System is not rendered inoperable by the accumulated gas (i.e. the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.

(continued)

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RHR Suppression Pool Spray B 3.6.2.4 BASES SURVEILLANCE SR 3.6.2.4.2 (continued)

REQUIREMENTS RHR Suppression Pool Spray System locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subiect to the same gas intrusion mechanisms may be verified by monitoring a representative sub- set of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety.

For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location.

Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

SR 3.6.2.4.3 This Surveillance is performed every 10 years to verify that the spray nozzles are not obstructed and that flow will be provided when required. The Surveillance Fequency is controlled under the Surveillance Frequency Control Program.

REFERENCES 1. FSAR, Sections 5.2 and 14.4.3.

2. NRC No.93-102, "Final Policy Statement on Technical Specification Improvements," July 23, 1993.

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RHR Drywell Spray B 3.6.2.5 BASES (continued)

APPLICABLE The RHR drywell spray is credited post-LOCA for scrubbing inorganic SAFETY ANALYSES iodines and particulates from the primary containment atmosphere.

This function reduces the amount of airborne activity available for leakage from the primary containment. The RHR drywell spray also reduces the temperature and pressure in the drywell over time, thereby reducing the post-LOCA primary containment and main steam isolation valve leakage to within the assumptions of the Hatch radiological dose analysis. The RHR drywell spray system is not required to maintain the primary containment peak post-LOCA pressure within design limits.

Reference 2 contains the results of analyses used to predict the effects of drywell spray on the post accident primary containment atmosphere, as well as the primary containment leak rate analysis.

The RHR drywell spray system satisfies criterion 3 of the NRC Policy Statement (Reference 3).

LCO In the event of a LOCA, a minimum of one RHR drywell spray subsystem using one RHR pump is required to adequately scrub the inorganic iodines and particulates from the primary containment atmosphere. One RHR drywell spray system using one RHR pump is also adequate to reduce the primary containment temperature and pressure to maintain the primary containment and main steam isolation valve post-accident leakage rates within the limits assumed in the Hatch radiological dose analysis.

To ensure these requirements are met, two RHR drywell spray subsystems must be OPERABLE with power supplies from two safety related independent power supplies. Therefore, in the event of an accident, at least one subsystem is OPERABLE assuming the worst case single failure.

An RHR drywell spray subsystem is considered OPERABLE when one of the two pumps in the subsystem, the heat exchanger, associated piping, valves, instrumentation, and controls are OPERABLE. Management of gas voids is important to RHR Drvwell Spray System OPERABILITY.

Each RHR drywell spray subsystem is supported by an independent subsystem of the RHRSW system. Specifically, two RHRSW pumps and an OPERABLE flow path are required to provide the necessary heat transfer from the heat exchanger and thereby support each drywell spray subsystem.

(continued)

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RHR Drywell Spray B 3.6.2.5 BASES (continued)

SURVEILLANCE SR 3.6.2.5.1 REQUIREMENTS Verifying the correct alignment for manual, power operated, and automatic valves in the RHR drywell spray flow path provides assurance that the proper flow paths will exist for system operation.

This SR does not apply to valves that are locked, sealed, or otherwise secured in position since these valves were verified to be in the correct position prior to locking, sealing, or securing.

A valve is also allowed to be in the non-accident position provided it can be aligned to the accident position within the time assumed in the accident analysis. This is acceptable since the RHR drywell spray mode is manually initiated. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of being mispositioned are in the correct position. This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

SR 3.6.2.5.2 RHR Drywell Spray System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR Drywell Spray systems and may also prevent water hammer and pump cavitation.

Selection of RHR Drywell Spray System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The RHR Drywell Spray System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined (continued)

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RHR Drywell Spray B 3.6.2.5 BASES (continued)

SURVEILLANCE SR 3.6.2.5.2 (continued)

REQUIREMENTS by subsequent evaluation that the RHR Drywell Spray System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met.

Accumulated gas should be eliminated or brought within the acceptance criteria limits.

RHR Drywell Spray System locations susceptible to gas accumulation are monitored and, ifgas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subiect to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or Personnel safety. For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location. Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

SR 3.6.2.5.3 This surveillance is performed following maintenance which could result in nozzle blockage to verify that the spray nozzles are not obstructed and that flow will be provided when required. The frequency is adequate to detect degradation in performance due to the passive nozzle design and its normally dry state and has been shown to be acceptable through operating experience.

REFERENCES 1. FSAR Section 4.8.

2. Unit 2 FSAR, Section 15.3.

3. NRC No.93-102, "Final Policy Statement on Technical Specification Improvements," July 23, 1993.

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RHR - High Water Level B 3.9.7 BASES LCO reactor coolant temperature in the desired range, valves, piping, (continued) instruments, and controls to ensure an OPERABLE flow path. In MODE 5, the RHR cross tie valve is not required to be closed; thus, the valve may be opened to allow RHR pumps in one loop to discharge through the opposite recirculation loop to make a complete subsystem. In addition, the RHRSAW cross tie valves may be open to allow RHRSW pumps in one loop to provide cooling to a heat exchanger in the opposite loop to make a complete subsystem.

Management of gas voids is important to RHR Shutdown Cooling System OPERABILITY.

Additionally, each RHR shutdown cooling subsystem is considered OPERABLE if it can be manually aligned (remote or local) in the shutdown cooling mode for removal of decay heat. Operation (either continuous or intermittent) of one subsystem can maintain and reduce the reactor coolant temperature as required (sufficient to maintain reactor coolant temperature in the desired range). However, to ensure adequate core flow to allow for accurate average reactor coolant temperature monitoring, nearly continuous operation is required. A Note is provided to allow a 2 hour2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months exception to shut down the operating subsystem every 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months .

The LCO consists of two separate requirements. Either requirement can be not met (and the associated Condition entered) without necessarily affecting the other (and without necessarily entering the other associated Condition). For example, an operating RHR shutdown cooling subsystem can be removed from operation, yet remain OPERABLE for the decay heat removal function. (Manual alignment and operation can satisfy OPERABILITY.) Conversely, an RHR shutdown cooling subsystem (or recirculation pump) can remain in operation, circulating reactor coolant; however, if the RHR heat exchanger cannot remove decay heat, the subsystem is inoperable.

The LCO Notes follow this separation of requirements: an exception to circulating reactor coolant (Note 1) does not result in an exception to the OPERABILITY requirement, and an exception to the RHR shutdown cooling subsystem OPERABILITY requirements does not result in an exception to the requirement for circulating reactor coolant (Note 2).

APPLICABILITY One RHR shutdown cooling subsystem must be OPERABLE and in operation in MODE 5, with irradiated fuel in the RPV and the water level > 22 ft 1/8 inches above the top of the RPV flange, to provide decay heat removal. RHR shutdown cooling subsystem requirements in other MODES are covered by LCOs in Section 3.4, Reactor Coolant System (RCS). RHR Shutdown Cooling subsystem requirements in MODE 5 with irradiated fuel in the RPV and the water (continued)

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RHR - High Water Level B 3.9.7 BASES (continued)

ACTIONS B.1, B.2, B.3, and B.4 (continued) isolation capability. The administrative controls can consist of stationing a dedicated operator, who is in continuous communication with the control room, at the controls of the isolation device. In this way, the penetration can be rapidly isolated when a need for secondary containment isolation is indicated.). This may be performed as an administrative check, by examining logs or other information to determine whether the components are out of service for maintenance or other reasons. It is not necessary to perform the Surveillances needed to demonstrate the OPERABILITY of the components. If, however, any required component is inoperable, then it must be restored to OPERABLE status. In this case, a Surveillance may need to be performed to restore the component to OPERABLE status. Actions must continue until all required components are OPERABLE.

C.1 and C.2 If no RHR shutdown cooling subsystem is in operation, an alternate method of coolant circulation is required to be established within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months . The Completion Time is modified such that the 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months is applicable separately for each occurrence involving a loss of coolant circulation.

During the period when the reactor coolant is being circulated by an alternate method (other than by the required RHR shutdown cooling subsystem), the reactor coolant temperature must be periodically monitored to ensure proper functioning of the alternate method. The once per hour Completion Time is deemed appropriate.

SURVEILLANCE SR 3.9.7.1 REQUIREMENTS This Surveillance demonstrates that the required RHR shutdown cooling subsystem is in operation and circulating reactor coolant. The required flow rate is determined by the flow rate necessary to provide sufficient decay heat removal capability. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

SR 3.9.7.2 RHR Shutdown Cooling System piping and components have the potential to develop voids and pockets of entrained gases.

Preventing and managing gas intrusion and accumulation is necessary for proper operation of the required RHR shutdown (continued)

HATCH UNIT 1 B 3.9-22 REVISION r9-9 I to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR - High Water Level B 3.9.7 BASES SURVEILLANCE SR 3.9.7.2 (continued)

REQUIREMENTS cooling subsystem(s) and may also prevent water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel.

Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The RHR Shutdown Cooling System is OPERABLE when it is sufficiently filled with water. For the RHR SDC piping on the discharge side of the RHR pump, acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume in the RHR SDC piping on the discharge side of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water),

the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits. Since the RHR SDC piping on the discharge side of the pump is the same as the Low Pressure Coolant Injection piping, performances of surveillances for ECCS TS may satisfy the requirements of this surveillance. For the RHR SDC piping on the suction side of the RHR pump, the surveillance is met by virtue of the performance of operating procedures that ensure that the RHR SDC suction piping is adequately filled and vented. The performance of these manual actions ensures that the surveillance is met.

RHR SDC System locations on the discharge side of the RHR pump susceptible to gas accumulation are monitored and, if gas is found, the gas volume is compared to the acceptance criteria for the location.

Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety.

(continued)

HATCH UNIT 1 B 3.9-23 REVISION 69 1 to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR - High Water Level B 3.9.7 BASES SURVEILLANCE SR 3.9.7.2 (continued)

REQUIREMENTS For these locations alternative methods (e.g.. operating parameters, remote monitoring) may be used to monitor the susceptible location.

Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The SR can be met by virtue of having an RHR SDC subsystem in service in accordance with operating procedures.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

REFERENCES 1. 10 CFR 50, Appendix A, GDC 34.

2. Technical Requirements Manual, Section 8.0.

3. NRC No.93-102, "Final Policy Statement on Technical Specification Improvements," July 23, 1993.

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RHR - LowWater Level B 3.9.8 B 3.9 REFUELING OPERATIONS B 3.9.8 Residual Heat Removal (RHR) - LowWater Level BASES BACKGROUND The purpose of the RHR System in MODE 5 is to remove decay heat and sensible heat from the reactor coolant, as required by GDC 34 (Ref. 1). Each of the two shutdown cooling loops of the RHR System can provide the required decay heat removal. Each loop consists of two motor driven pumps, a heat exchanger, and associated piping and valves. Both loops have a common suction from the same recirculation loop. Each pump discharges the reactor coolant, after it has been cooled by circulation through the respective heat exchangers, to the reactor via the associated recirculation loop. The RHR heat exchangers transfer heat to the RHR Service Water System. The RHR shutdown cooling mode is manually controlled.

APPLICABLE With the unit in MODE 5, the RHR System is not required to SAFETY ANALYSES mitigate any events or accidents evaluated in the safety analyses.

The RHR System is required for removing decay heat to maintain the temperature of the reactor coolant.

The RHR System satisfies Criterion 4 of the NRC Policy Statement (Ref. 3).

LCO In MODE 5 with irradiated fuel in the reactor pressure vessel (RPV) and the water level < 22 ft 1/8 inches above the RPV flange, two RHR shutdown cooling subsystems must be OPERABLE.

An OPERABLE RHR shutdown cooling subsystem consists of an RHR pump and the associated heat exchanger, an RHRSW pump providing cooling to the heat exchanger with sufficient flow to maintain reactor coolant temperature in the desired range, valves, piping, instruments, and controls to ensure an OPERABLE flow path. The two required RHR shutdown cooling subsystems have a common suction source and are allowed to have a common heat exchanger and common discharge piping. Management of gas voids is important to RHR Shutdown Cooling System OPERABILITY.

Since the piping and heat exchangers are passive components that are assumed not to fail, they are allowed to be common to both subsystems. Thus, to meet the LCO, both RHR pumps in one loop or (continued)

HATCH UNIT 1 B 3.9-24 REVISION 4 1 to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR - Low Water Level B 3.9.8 BASES (continued)

SURVEILLANCE SR 3.9.8.1 REQUIREMENTS This Surveillance demonstrates that one required RHR shutdown cooling subsystem is in operation and circulating reactor coolant. The required flow rate is determined by the flow rate necessary to provide sufficient decay heat removal capability. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

SR 3.9.8.2 RHR Shutdown Cooling System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessaryfor proper operation of the RHR shutdown cooling subsystems and may also prevent water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel.

Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration.

Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The RHR Shutdown Cooling System is OPERABLE when it is sufficiently filled with water. For the RHR SDC piping on the discharge side of the RHR pump, acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume in the RHR SDC piping on the discharge side of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water),

the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits. Since the RHR SDC piping on the discharge side of the pump is the same as the Low Pressure Coolant Iniection piping, performances of surveillances for ECCS TS may satisfy the requirements of this (continued)

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RHR - LowWater Level B 3.9.8 BASES SURVEILLANCE SR 3.9.8.2 (continued)

REQUIREMENTS surveillance. For the RHR SDC piping on the suction side of the RHR pump, the surveillance is met by virtue of the performance of operating procedures that ensure that the RHR SDC suction piping is adequately filled and vented. The performance of these manual actions ensures that the surveillance is met.

RHR SDC System locations on the discharge side of the RHR pump susceptible to gas accumulation are monitored and, ifgas is found, the gas volume is compared to the acceptance criteria for the location.

Susceptible locations in the same system flow path which are subiect to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety.

For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location.

Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The SR can be met by virtue of having an RHR SDC subsystem in service in accordance with operating procedures.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

REFERENCES 1. 10 CFR 50, Appendix A, GDC 34.

2. Technical Requirements Manual, Section 8.0.

3. NRC No.93-102, "Final Policy Statement on Technical HATCH UNIT 1 B 3.9-29 REVISION &9 1 to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR Shutdown Cooling System - Hot Shutdown B 3.4.7 BASES LCO decreased to < 212°F within the time limit specified in Regulatory (continued) Guide 1.139, "Guidance for Residual Heat Removal," assuming two RHRSW System pumps are in operation. OPERABILITY requirements for the RHRSW System in Mode 3 are addressed by LCO 3.7.1, "Residual Heat Removal Service Water (RHRSW)

System."

The two required RHR shutdown cooling subsystems have a common suction source and are allowed to have a common heat exchanger and common discharge piping. Since the piping and heat exchangers are passive components that are assumed not to fail, they are allowed to be common to both required subsystems. Thus, to meet the LCO, both RHR pumps in one loop or one RHR pump in each of the two loops must be OPERABLE. If the two required subsystems consist of an RHR pump in each loop, both heat exchangers, each with two OPERABLE RHRSW System pumps supplying cooling water, are required since one heat exchanger will not be common to both subsystems. Each shutdown cooling subsystem is considered OPERABLE if it can be manually aligned (remote or local) in the shutdown cooling mode for removal of decay heat. In MODE 3, one RHR shutdown cooling subsystem can provide the required cooling (sufficient to reduce and maintain reactor coolant temperature

< 212 0 F), but two subsystems are required to be OPERABLE to provide redundancy. Operation of one subsystem can maintain or reduce the reactor coolant temperature as required. However, to ensure adequate core flow to allow for accurate average reactor coolant temperature monitoring, nearly continuous operation is required. Management of gas voids is important to RHR Shutdown Cooling System OPERABILITY. In MODE 3, the RHR cross tie valve (2E1 1-FO10) may not be opened (per LCO 3.5.1) to allow pumps in one loop to discharge through the opposite recirculation loop.

Note 1 permits both RHR shutdown cooling subsystems and recirculation pumps to be shut down for a period of 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months in an 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months period. Note 2 allows one RHR shutdown cooling subsystem to be inoperable for up to 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months for performance of Surveillance tests. These tests may be on the affected RHR System or on some other plant system or component that necessitates placing the RHR System in an inoperable status during the performance. This is permitted because the core heat generation can be low enough and the heatup rate slow enough to allow some changes to the RHR subsystems or other operations requiring RHR flow interruption and loss of redundancy.

The LCO consists of two separate requirements. Either requirement can be not met (and the associated Condition entered) without necessarily affecting the other (and without necessarily entering the (continued)

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RHR Shutdown Cooling System - Hot Shutdown B 3.4.7 BASES SURVEILLANCE SR 3.4.7.1 (continued)

REQUIREMENTS This Surveillance is modified by a Note allowing sufficient time to align the RHR System for shutdown cooling operation after clearing the pressure interlock that isolates the system, or for placing a recirculation pump in operation. The Note takes exception to the requirements of the Surveillance being met (i.e., forced coolant circulation is not required for this initial 2 hour2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months period), which also allows entry into the Applicability of this Specification in accordance with SR 3.0.4 since the Surveillance will not be "not met" at the time of entry into the Applicability.

R 3.4.7.2 RHR Shutdown Cooling System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR shutdown cooling subsystems and may also prevent water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel.

Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The RHR Shutdown Cooling System is OPERABLE when it is sufficiently filled with water. For the RHR SDC piping on the discharge side of the RHR pump, acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume in the RHR SDC piping on the discharge side of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water),

the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits. Since the RHR SDC piping on the discharge side of the pump is the same as (continued)

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RHR Shutdown Cooling System - Hot Shutdown B 3.4.7 BASES SURVEILLANCE SR 3.4.7.2 (continued)

REQUIREMENTS the Low Pressure Coolant Iniection piping, performances of surveillances for ECCS TS may satisfy the requirements of this surveillance. For the RHR SDC piping on the suction side of the RHR pump, the surveillance is met by virtue of the performance of operating procedures that ensure that the RHR SDC suction piping is adequately filled and vented. The performance of these manual actions ensures that the surveillance is met.

RHR SDC System locations on the discharge side of the RHR pump susceptible to qas accumulation are monitored and, ifgas is found, the gas volume is compared to the acceptance criteria for the location.

Susceptible locations in the same system flow path which are subiect to the same gas intrusion mechanisms may be verified by monitorinq a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety.

For these locations alternative methods (e.g., operating parameters, remote monitorinq) may be used to monitor the susceptible location.

Monitorinq is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenqe system OPERABILITY. The accuracy of the method used for monitorinq the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The SR may be met for one RHR SDC subsystem by virtue of having a subsystem in service in accordance with operating procedures.

This SR is modified by a Note that states the SR is not required to be performed until 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam dome pressure is less than the RHR low pressure permissive pressure. In a rapid shutdown, there may be insufficient time to verify all susceptible locations prior to entering the Applicability.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

REFERENCES 1. NRC No.93-102, "Final Policy Statement on Technical Specification Improvements," July 23, 1993.

HATCH UNIT 2 B 3.4-35 REVISION 7-7 ý to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR Shutdown Cooling System - Cold Shutdown B 3.4.8 BASES LCO loops must be OPERABLE. Ifthe two required subsystems consist of (continued) an RHR pump in each loop, both heat exchangers are required since one heat exchanger will not be common to both subsystems. In MODE 4, the RHR cross tie valve (2E1 1-FO10) may be opened (per LCO 3.5.2) to allow pumps in one loop to discharge through the opposite recirculation loop to make a complete subsystem.

Similarly, to meet the LCO, the cooling supply for the heat exchanger(s) requires two RHRSW pumps (either one pump in each RHRSW loop or two pumps in one RHRSW loop). With one RHR heat exchanger common to both RHR shutdown cooling subsystems, each RHRSW pump is required to be capable of providing cooling to that heat exchanger (Note: the RHRSW cross tie valves may be open to allow the RHRSW pump(s) in one loop to provide cooling to a heat exchanger in the opposite loop to make a complete subsystem.), or with both heat exchangers required, each heat exchanger is required to have an RHRSW pump capable of providing coolant to that heat exchanger.

Additionally, each shutdown cooling subsystem is considered OPERABLE if it can be manually aligned (remote or local) in the shutdown cooling mode for removal of decay heat. In MODE 4, one RHR shutdown cooling subsystem can provide the required cooling (sufficient to maintain reactor coolant temperature < 212 0 F), but two subsystems are required to be OPERABLE to provide redundancy.

Operation of one subsystem can maintain or reduce the reactor coolant temperature as required. However, to ensure adequate core flow to allow for accurate average reactor coolant temperature monitoring, nearly continuous operation is required. Management of gas voids is important to RHR Shutdown Cooling System OPERABILITY.

Note 1 permits both RHR shutdown cooling subsystems and recirculation pumps to be shut down for a period of 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months in an 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months period. Note 2 allows one RHR shutdown cooling subsystem to be inoperable for up to 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months for performance of Surveillance tests. These tests may be on the affected RHR System or on some other plant system or component that necessitates placing the RHR System in an inoperable status during the performance. This is permitted because the core heat generation can be low enough and the heatup rate slow enough to allow some changes to the RHR subsystems or other operations requiring RHR flow interruption and loss of redundancy.

The LCO consists of two separate requirements. Either requirement can be not met (and the associated Condition entered) without necessarily affecting the other (and without necessarily entering the (continued)

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RHR Shutdown Cooling System - Cold Shutdown B 3.4.8 BASES ACTIONS B.1 and B.2 (continued) function and is modified such that the 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months is applicable separately for each occurrence involving a loss of coolant circulation.

Furthermore, verification of the functioning of the alternate method must be reconfirmed every 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months thereafter. This will provide assurance of continued temperature monitoring capability.

During the period when the reactor coolant is being circulated by an alternate method (other than by the required RHR shutdown cooling subsystem or recirculation pump), the reactor coolant temperature and pressure must be periodically monitored to ensure proper function of the alternate method. The once per hour Completion Time is deemed appropriate.

SURVEILLANCE SR 3.4.8.1 REQUIREMENTS This Surveillance verifies that one RHR shutdown cooling subsystem or recirculation pump is in operation and circulating reactor coolant.

The required flow rate is determined by the flow rate necessary to provide sufficient decay heat removal capability. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

SR 3.4.8.2 RHR Shutdown Cooling System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR shutdown cooling subsystems and may also prevent water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel.

Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

(continued)

HATCH UNIT 2 B 3.4-39 REVISION 7-9 1 to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR Shutdown Cooling System - Cold Shutdown B 3.4.8 BASES SURVEILLANCE SR 3.4.8.2 (continued)

REQUIREMENTS The RHR Shutdown Cooling System is OPERABLE when it is sufficiently filled with water. For the RHR SDC piping on the discharge side of the RHR pump, acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume in the RHR SDC piping on the discharge side of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water),

the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits. Since the RHR SDC piping on the discharge side of the pump is the same as the Low Pressure Coolant Iniection piping, performances of surveillances for ECCS TS may satisfy the requirements of this surveillance. For the RHR SDC piping on the suction side of the RHR pump, the surveillance is met by virtue of the performance of operating procedures that ensure that the RHR SDC suction piping is adequately filled and vented. The performance of these manual actions ensures that the surveillance is met.

RHR Shutdown Cooling System locations susceptible to gas accumulation are monitored and, ifgas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subiect to the same gas intrusion mechanisms may be verified by monitoring a representative sub- set of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety.

For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location.

Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The SR may be met for one RHR SDC subsystem by virtue of having a subsystem in service in accordance with operating procedures.

(continued)

HATCH UNIT 2 B 3.4-40 REVISION 7-9 1 to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

RHR Shutdown Cooling System - Cold Shutdown B 3.4.8 BASES SURVEILLANCE SR 3.4.8.2 (continued)

REQUIREMENTS The Surveillance Frequency is controlled under the Surveillance Frequency Control Prog.ram. The Surveillance Frequency may vary by location susceptible to gas accumulation.

REFERENCES 1. NRC No.93-102, "Final Policy Statement on Technical Specification Improvements," July 23, 1993.

HATCH UNIT 2 B 3.4-41 REVISION 7-9 1 to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

ECCS - Operating B 3.5.1 BASES (continued)

APPLICABLE The ECCS performance is evaluated for the entire spectrum of SAFETY ANALYSES break sizes for a postulated LOCA. The accidents for which ECCS operation is required are presented in References 5, 6, and 7. The required analyses and assumptions are defined in Reference 8. The results of these analyses are also described in References 9 and 10.

This LCO helps to ensure that the following acceptance criteria for the ECCS, established by 10 CFR 50.46 (Ref. 11), will be met following a LOCA, assuming the worst case single active component failure in the ECCS:

a. Maximum fuel element cladding temperature is < 2200°F;

b. Maximum cladding oxidation is < 0.17 times the total cladding thickness before oxidation;

c. Maximum hydrogen generation from a zirconium water reaction is < 0.01 times the hypothetical amount that would be generated if all of the metal in the cladding surrounding the fuel, excluding the cladding surrounding the plenum volume, were to react;

d. The core is maintained in a coolable geometry; and e.

Adequate long term cooling capability is maintained. The limiting single failures are discussed in Reference 10. The remaining OPERABLE ECCS subsystems provide the capability to adequately cool the core and prevent excessive fuel damage.

The ECCS satisfy Criteria 3 and 4 of the NRC Policy Statement (Ref. 13).

LCO Each ECCS injection/spray subsystem and six of seven ADS valves are required to be OPERABLE. The ECCS injection/spray subsystems are defined as the two CS subsystems, the two LPCI subsystems, and one HPCI System. The low pressure ECCS injection/spray subsystems are defined as the two CS subsystems and the two LPCI subsystems. Management of gas voids is important to ECCS iniection/spray subsystem OPERABILITY.

With less than the required number of ECCS subsystems OPERABLE, the potential exists that during a limiting design basis LOCA concurrent with the worst case single failure, the limits specified in Reference 11 could be exceeded. All low pressure ECCS (continued)

HATCH UNIT 2 B 3.5-4 REVISION 43 1 to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

ECCS - Operating B 3.5.1 BASES (continued)

SURVEILLANCE SR 3.5.1.1 REQUIREMENTS The ECCS injection/spray subsystem flow path piping and components has have the potential to develop voids and pockets of entrained aifgases. Maintaining the pump discharge lines of the HPI System*,

GS System, and LIPCI subsystems full of Ater ensures that the-EGGS will perform properly, injecting its full Gapacity itnt the ROS upon demand. This "willals Preventing and managing gas intrusion and accumulation is necessary for proper operation of the ECCS iniection/spray subsystems and may also prevent a water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel. follo-ing an ECCS initiation signal. One accGeptable mcthod of, en.uring that,*the ine are.ful,ist vent at the high point-.

In addition, when HPCI is aligned to the suppression pool (instead of the CST), one acceptable method is to monitor pump suction pressure.

Selection of ECCS iniection/spray subsystem locations susceptible to gas accumulation is based on a review of system design information including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations.

The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The ECCS iniection/spray subsystem is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the ECCS iniection/spray subsystems are not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.

ECCS iniection/spray subsystem locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are submect to the same gas intrusion mechanisms may be verified by monitoring a (continued)

HATCH UNIT 2 B 3.5-8 REVISION 7-9 ý to NL-14-1349 HNP Technical Specification Bases Marked Up Pages (for information only)

ECCS - Operating B 3.5.1 BASES SURVEILLANCE SR 3.5.1.1 (continued)

REQUIREMENTS representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant confiquration, or personnel safety.

For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location.

Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

SR 3.5.1.2 Verifying the correct alignment for manual, power operated, and automatic valves in the ECCS flow paths provides assurance that the proper flow paths will exist for ECCS operation. This SR does not apply to valves that are locked, sealed, or otherwise secured in position since these were verified to be in the correct position prior to locking, sealing, or securing. A valve that receives an initiation signal is allowed to be in a nonaccident position provided the valve will automatically reposition in the proper stroke time. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of potentially being mispositioned are in the correct position. This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.

For the HPCI System, this SR also includes the steam flow path for the turbine and the flow controller position.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

This SR is modified by a Note 1 that allows LPCI subsystems to be considered OPERABLE during alignment and operation for decay heat removal with reactor steam dome pressure less than the RHR low pressure permissive pressure in MODE 3, if capable of being manually realigned (remote or local) to the LPCI mode and not otherwise inoperable. This allows operation in the RHR shutdown cooling mode during MODE 3, if necessary.

(continued)

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ECCS - Operating B 3.5.1 BASES SURVEILLANCE SR 3.5.1.2 (continued)

REQUIREMENTS The Surveillance is also modified by a Note 2 which exempts system vent flow paths opened under administrative control. The administrative control should be proceduralized and include stationing a dedicated individual who can rapidly close the system vent flow path if directed SR 3.5.1.3 Verification that ADS air supply header pressure is > 90 psig ensures adequate air pressure for reliable ADS operation. The accumulator on each ADS valve provides pneumatic pressure for valve actuation.

The design pneumatic supply pressure requirements for the accumulator are such that, following a failure of the pneumatic supply to the accumulator, at least two valve actuations can occur with the drywell at 70% of design pressure (Ref. 12). The ECCS safety analysis assumes only one actuation to achieve the depressurization required for operation of the low pressure ECCS. This minimum required pressure of > 90 psig for one actuation is provided by the ADS instrument air supply. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

SR 3.5.1.4 Verification that the RHR System cross tie valve is closed and power to its operator is disconnected ensures that each LPCI subsystem remains independent and a failure of the flow path in one subsystem will not affect the flow path of the other LPCI subsystem. Acceptable methods of removing power to the operator include de-energizing breaker control power or racking out or removing the breaker. If the RHR System cross tie valve is open or power has not been removed from the valve operator, both LPCI subsystems must be considered inoperable. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

SR 3.5.1.5 (Not used.)

SR 3.5.1.6 Cycling the recirculation pump discharge valves through one complete cycle of full travel demonstrates that the valves are mechanically OPERABLE and will close when required. Upon initiation of an automatic LPCI subsystem injection signal, these valves are required (continued)

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ECCS - Shutdown B 3.5.2 B 3.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) AND REACTOR CORE ISOLATION COOLING (RCIC) SYSTEM B 3.5.2 ECCS - Shutdown BASES BACKGROUND A description of the Core Spray (CS) System and the low pressure coolant injection (LPCI) mode of the Residual Heat Removal (RHR)

System is provided in the Bases for LCO 3.5.1, "ECCS - Operating."

APPLICABLE The ECCS performance is evaluated for the entire spectrum of SAFETY ANALYSES break sizes for a postulated loss of coolant accident (LOCA). The long term cooling analysis following a design basis LOCA (Ref. 1) demonstrates that only one low pressure ECCS injection/spray subsystem is required, post LOCA, to maintain adequate reactor vessel water level in the event of an inadvertent vessel draindown. It is reasonable to assume, based on engineering judgment, that while in MODES 4 and 5, one low pressure ECCS injection/spray subsystem can maintain adequate reactor vessel water level. To provide redundancy, a minimum of two low pressure ECCS injection/spray subsystems are required to be OPERABLE in MODES 4 and 5.

The low pressure ECCS subsystems satisfy Criterion 3 of the NRC Policy Statement (Ref. 3).

LCO Two low pressure ECCS injection/spray subsystems are required to be OPERABLE. The low pressure ECCS injection/spray subsystems consist of two CS subsystems and two LPCI subsystems. Each CS subsystem consists of one motor driven pump, piping, and valves to transfer water from the suppression pool or condensate storage tank (CST) to the reactor pressure vessel (RPV). Each LPCI subsystem consists of one motor driven pump, piping, and valves to transfer water from the suppression pool to the RPV. Only a single LPCI pump is required per subsystem because of the larger injection capacity in relation to a CS subsystem. In MODES 4 and 5, the RHR System cross tie valve is not required to be closed. Management of

.gas voids is important to ECCS iniection/spray subsystem OPERABILITY. The necessary portions of the Plant Service Water System are also required to provide appropriate cooling to each required ECCS subsystem.

(continued)

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ECCS - Shutdown B 3.5.2 BASES SURVEILLANCE SR 3.5.2.3, SR 3.5.2.5, and SR 3.5.2.6 REQUIREMENTS (continued) The Bases provided for SR 3.5.1.1, SR 3.5.1.7, and SR 3.5.1.10 are applicable to SR 3.5.2.3, SR 3.5.2.5, and SR 3.5.2.6, respectively.

However, the LPCI flow rate requirement for SR 3.5.2.5 is based on a single pump, not the two pump flow rate requirement of SR 3.5.1.7.

SR 3.5.2.4 Verifying the correct alignment for manual, power operated, and automatic valves in the ECCS flow paths provides assurance that the proper flow paths will exist for ECCS operation. This SR does not apply to valves that are locked, sealed, or otherwise secured in position, since these valves were verified to be in the correct position prior to locking, sealing, or securing. A valve that receives an initiation signal is allowed to be in a nonaccident position provided the valve will automatically reposition in the proper stroke time. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of potentially being mispositioned are in the correct position. This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

In MODES 4 and 5, the RHR System may operate in the shutdown cooling mode to remove decay heat and sensible heat from the reactor. Therefore, RHR valves that are required for LPCI subsystem operation may be aligned for decay heat removal. Therefore, this SR is modified by a Note 1 that allows one LPCI subsystem of the RHR System to be considered OPERABLE for the ECCS function if all the required valves in the LPCI flow path can be manually realigned (remote or local) to allow injection into the RPV, and the system is not otherwise inoperable. This will ensure adequate core cooling if an inadvertent RPV draindown should occur.

The Surveillance is also modified by a Note 2 which exempts system vent flow paths opened under administrative control. The administrative control should be proceduralized and include stationing a dedicated individual who can rapidly close the system vent flow path ifdirected.

(continued)

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RCIC System B 3.5.3 BASES BACKGROUND when other discharge line valves are closed. To ensure rapid delivery (continued) of water to the RPV and to minimize water hammer effects, the RCIC System discharge piping is kept full of water. The RCIC System is normally aligned to the CST. The height of water in the CST is sufficient to maintain the piping full of water up to the first isolation valve. The relative height of the feedwater line connection for RCIC is such that the water in the feedwater lines keeps the remaining portion of the RCIC discharge line full of water. Therefore, RCIC does not require a "keep fill" system.

APPLICABLE The function of the RCIC System is to respond to transient events by SAFETY ANALYSES providing makeup coolant to the reactor. The RCIC System is not an Engineered Safety Feature System and no credit is taken in the safety analyses for RCIC System operation. Based on its contribution to the reduction of overall plant risk, however, the system satisfies Criterion 4 of the NRC Policy Statement (Ref. 5).

LCO The OPERABILITY of the RCIC System provides adequate core cooling such that actuation of any of the low pressure ECCS subsystems is not required in the event of RPV isolation accompanied by a loss of feedwater flow. The RCIC System has sufficient capacity for maintaining RPV inventory during an isolation event. Management of gas voids is important to RCIC System OPERABILITY.

APPLICABILITY The RCIC System is required to be OPERABLE during MODE 1, and MODES 2 and 3 with reactor steam dome pressure > 150 psig, since RCIC is the primary non-ECCS water source for core cooling when the reactor is isolated and pressurized. In MODES 2 and 3 with reactor steam dome pressure < 150 psig, and in MODES 4 and 5, RCIC is not required to be OPERABLE since the low pressure ECCS injection/spray subsystems can provide sufficient flow to the RPV.

ACTIONS A Note prohibits the application of LCO 3.0.4.b to an inoperable RCIC subsystem. There is an increased risk associated with entering a MODE or other specified condition in the Applicability with an inoperable RCIC subsystem, and the provisions of LCO 3.0.4.b, which allows entry into a MODE or other specified condition in the Applicability with the LCO not met after performance of a risk assessment addressing inoperable systems and components, should ot be applied in this circumstance.

(continued)

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RCIC System B 3.5.3 BASES (continued)

SURVEILLANCE SR 3.5.3.1 REQUIREMENTS The RCIC System flow path piping and components have has-the potential to develop voids and pockets of entrained airgases.

Maintaini* n the pump disc.harge lffine of the ROIC Sy*tem fuill of water ensur~es that the systemn will pertol~ properly, injecting its fullcpit into the Reac;rtor Coolant System; upon demand. This;A1 AIas revn a; wMatr hammer follow-ng an "*itiatiG- GýRal. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RCIC System and may also prevent a water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel. One acceptable method of ensuring the line is full when aligned to the CST- is to vent at the high poi;nt and, hen alignRed to the suppression pool, is by monitoring pump suction pressure.

Selection of RCIC System locations susceptible to gas accumulation is based on a self-assessment of the piping confiquration to identify where gases may accumulate and remain even after the system is filled and vented, and to identify vulnerable potential degassing flow paths. The review is supplemented by verification that installed hig'h-point vents are actually at the system high points, including field verification to ensure pipe shapes and construction tolerances have not inadvertently created additional high points. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The RCIC System is OPERABLE when it is sufficiently filled with water.

Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RCIC Systems are not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.

RCIC System locations susceptible to gas accumulation are monitored and, ifgas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative sub-set of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or Personnel safety. For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used (continued)

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RCIC System B 3.5.3 BASES SURVEILLANCE SR 3.5.3.1 (continued)

REQUIREMENTS to monitor the susceptible location. Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The Surveillance Frequency is controlled under the surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

SR 3.5.3.2 Verifying the correct alignment for manual, power operated, and automatic valves in the RCIC flow path provides assurance that the proper flow path will exist for RCIC operation. This SR does not apply to valves that are locked, sealed, or otherwise secured in position since these valves were verified to be in the correct position prior to locking, sealing, or securing. A valve that receives an initiation signal is allowed to be in a nonaccident position provided the valve will automatically reposition in the proper stroke time. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of potentially being mispositioned are in the correct position. This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.

For the RCIC System, this SR also includes the steam flow path for the turbine and the flow controller position.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

The Surveillance is modified by a Note which exempts system vent flow paths opened under administrative control. The administrative control should be proceduralized and include stationing a dedicated individual who can rapidly close the system vent flow path if directed.

SR 3.5.3.3 and SR 3.5.3.4 The RCIC pump flow rates ensure that the system can maintain reactor coolant inventory during pressurized conditions with the RPV isolated. The required flow rate (400 gpm) is the pump design flow (continued)

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RHR Suppression Pool Cooling B 3.6.2.3 BASES (continued)

LCO During a DBA, a minimum of one RHR suppression pool cooling subsystem is required to maintain the primary containment peak pressure and temperature below design limits (Ref. 1). To ensure that these requirements are met, two RHR suppression pool cooling subsystems must be OPERABLE with power from two safety related independent power supplies. Therefore, in the event of an accident, at least one subsystem is OPERABLE assuming the worst case single active failure. An RHR suppression pool cooling subsystem is OPERABLE when one of the pumps, the heat exchanger, and associated piping, valves, instrumentation, and controls are OPERABLE. Management of gas voids is important to RHR Suppression Pool Cooling System OPERABILITY. Each RHR suppression pool cooling subsystem is supported by an independent subsystem of the Residual Heat Removal Service Water (RHRSWV)

System. Specifically, two OPERABLE RHRSVV pumps and an OPERABLE flow path, as defined in the Bases for LCO 3.7.1, "Residual Heat Removal Service Water (RHRSW) System," are required to provide the necessary heat transfer from the heat exchanger and, thereby, support each suppression pool cooling subsystem.

APPLICABILITY In MODES 1, 2, and 3, a DBA could cause a release of radioactive material to primary containment and cause a heatup and pressurization of primary containment. In MODES 4 and 5, the probability and consequences of these events are reduced due to the pressure and temperature limitations in these MODES. Therefore, the RHR Suppression Pool Cooling System is not required to be OPERABLE in MODE 4 or 5.

ACTIONS A.1 With one RHR suppression pool cooling subsystem inoperable, the inoperable subsystem must be restored to OPERABLE status within 7 days. In this Condition, the remaining RHR suppression pool cooling subsystem is adequate to perform the primary containment cooling function. However, the overall reliability is reduced because a single failure in the OPERABLE subsystem could result in reduced primary containment cooling capability. The 7 day Completion Time is acceptable in light of the redundant RHR suppression pool cooling capabilities afforded by the OPERABLE subsystem and the low probability of a DBA occurring during this period.

(continued)

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RHR Suppression Pool Cooling B 3.6.2.3 BASES SURVEILLANCE SR 3.6.2.3.2 REQUIREMENTS RHR Suppression Pool Cooling System piping and components have the potential to develop voids and pockets of entrained gases.

Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR suppression pool cooling subsystems and may also prevent water hammer and pump cavitation.

Selection of RHR Suppression Pool Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The RHR Suppression Pool Cooling System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Suppression Pool Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.

RHR Suppression Pool Cooling System locations susceptible to gas accumulation are monitored and, if gas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are submect to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety.

For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location.

Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations (continued)

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RHR Suppression Pool Cooling B 3.6.2.3 BASES SURVEILLANCE SR 3.6.2.3.2 (continued)

REQUIREMENTS and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

SR 3.6.2.3.3 Verifying that each required RHR pump develops a flow rate

> 7700 gpm while operating in the suppression pool cooling mode with flow through the associated heat exchanger ensures that pump performance has not degraded during the cycle. Flow is a normal test of centrifugal pump performance required by ASME Code,Section XI (Ref. 2). This test confirms one point on the pump design curve, and the results are indicative of overall performance. Such inservice tests confirm component OPERABILITY and detect incipient failures by indicating abnormal performance. The Frequency of this SR is in accordance with the Inservice Testing Program.

REFERENCES 1. FSAR, Section 6.2.2.

2. ASME, Boiler and Pressure Vessel Code,Section XI.

3. NRC No.93-102, "Final Policy Statement on Technical Specification Improvements," July 23, 1993.

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RHR Suppression Pool Spray B 3.6.2.4 BASES APPLICABLE containment conditions within design limits. The time history for SAFETY ANALYSES primary containment pressure is calculated to demonstrate that the (continued) maximum pressure remains below the design limit.

The RHR Suppression Pool Spray System satisfies Criterion 3 of the NRC Policy Statement (Ref. 2).

LCO In the event of a DBA, a minimum of one RHR suppression pool spray subsystem is required to mitigate potential bypass leakage paths and maintain the primary containment peak pressure below the design limits (Ref. 1). To ensure that these requirements are met, two RHR suppression pool spray subsystems must be OPERABLE with power from two safety related independent power supplies. Therefore, in the event of an accident, at least one subsystem is OPERABLE assuming the worst case single active failure. An RHR suppression pool spray subsystem is OPERABLE when one of the pumps, the heat exchanger, and associated piping, valves, instrumentation, and controls are OPERABLE. Management of gas voids is important to RHR Suppression Pool Spray System OPERABILITY. Each RHR suppression pool spray subsystem is supported by an independent subsystem of the Residual Heat Removal Service Water (RHRSW)

System. Specifically, two OPERABLE RHRSW pumps and an OPERABLE flow path, as defined in the Bases for LCO 3.7.1, "Residual Heat Removal Service Water (RHRSW) System," are required to provide the necessary heat transfer from the heat exchanger and, thereby, support each suppression pool spray subsystem.

APPLICABILITY In MODES 1, 2, and 3, a DBA could cause pressurization of primary containment. In MODES 4 and 5, the probability and consequences of these events are reduced due to the pressure and temperature limitations in these MODES. Therefore, maintaining RHR suppression pool spray subsystems OPERABLE is not required in MODE 4 or 5.

ACTIONS A.1 With one RHR suppression pool spray subsystem inoperable, the inoperable subsystem must be restored to OPERABLE status within 7 days. In this Condition, the remaining OPERABLE RHR (continued)

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RHR Suppression Pool Spray B 3.6.2.4 BASES SURVEILLANCE SR 3.6.2.4.1 (continued)

REQUIREMENTS accident analysis. This is acceptable since the RHR suppression pool cooling mode is manually initiated. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of being mispositioned are in the correct position. This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

SR 3.6.2.4.2 RHR Suppression Pool Spray System piping and components have the potential to develop voids and pockets of entrained gases.

Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR suppression pool spray subsystems and may also prevent water hammer and pump cavitation.

Selection of RHR Suppression Pool Spray System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations.

The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The RHR Suppression Pool Spray System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Suppression Pool Spray System is not rendered inoperable by the accumulated gas (i.e. the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.

(continued)

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RHR Suppression Pool Spray B 3.6.2.4 BASES SURVEILLANCE SR 3.6.2.4.2 (continued)

REQUIREMENTS RHR Suppression Pool Spray System locations susceptible to gas accumulation are monitored and, ifgas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative sub- set of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety.

For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location.

Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

SR 3.6.2.4.3 This Surveillance is performed every 10 years to verify that the spray nozzles are not obstructed and that flow will be provided when required. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

REFERENCES 1. FSAR, Section 6.2.

2. NRC No.93-102, "Final Policy Statement on Technical Specification Improvements," July 23, 1993.

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RHR Drywell Spray B 3.6.2.5 BASES (continued)

APPLICABLE The RHR Drywell Spray is credited post-LOCA for scrubbing inorganic SAFETY ANALYSES iodines and particulates from the primary containment atmosphere.

This function reduces the amount of airborne activity available for leakage from the primary containment. The RHR drywell spray also reduces the temperature and pressure in the drywell over time, thereby reducing the post-LOCA primary containment and main steam isolation valve leakage to within the assumptions of the Hatch radiological dose analysis. The RHR drywell spray system is not required to maintain the primary containment peak post-LOCA pressure within design limits.

Reference 2 contains the results of analyses used to predict the effects of drywell spray on the post accident primary containment atmosphere, as well as the primary containment leak rate analysis.

The RHR drywell spray system satisfies criterion 3 of the NRC Policy Statement (Reference 3).

LCO In the event of a LOCA, a minimum of one RHR drywell spray subsystem using one RHR pump is required to adequately scrub the inorganic iodines and particulates from the primary containment atmosphere. One RHR drywell spray system using one RHR pump is also adequate to reduce the primary containment temperature and pressure to maintain the primary containment and main steam isolation valve post-accident leakage rates within the limits assumed in the Hatch radiological dose analysis.

To ensure these requirements are met, two RHR drywell spray subsystems must be OPERABLE with power supplies from two safety related independent power supplies. Therefore, in the event of an accident, at least one subsystem is OPERABLE assuming the worst case single failure.

An RHR drywell spray subsystem is considered OPERABLE when one of the two pumps in the subsystem, the heat exchanger, associated piping, valves, instrumentation, and controls are OPERABLE. Management of gas voids is important to RHR Drywell Spray System OPERABILITY.

Each RHR drywell spray subsystem is supported by an independent subsystem of the RHRSW system. Specifically, two RHRSW pumps and an OPERABLE flow path are required to provide the necessary heat transfer from the heat exchanger and thereby support each drywell spray subsystem.

(continued)

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RHR Drywell Spray B 3.6.2.5 BASES (continued)

SURVEILLANCE SR 3.6.2.5.1 REQUIREMENTS Verifying the correct alignment for manual, power operated, and automatic valves in the RHR drywell spray flow path provides assurance that the proper flow paths will exist for system operation.

This SR does not apply to valves that are locked, sealed, or otherwise secured in position since these valves were verified to be in the correct position prior to locking, sealing, or securing.

A valve is also allowed to be in the non-accident position provided it can be aligned to the accident position within the time assumed in the accident analysis. This is acceptable since the RHR drywell spray mode is manually initiated. This SR does not require any testing or valve manipulation; rather, it involves verification that those valves capable of being mispositioned are in the correct position. This SR does not apply to valves that cannot be inadvertently misaligned, such as check valves.

The Frequency of 31 days is justified because the valves are operated under procedural control, improper valve position would affect only a single subsystem, the probability of an event requiring initiation of the system is low, and the subsystem is manually initiated. This Frequency has been shown to be acceptable based on operating experience.

SR 3.6.2.5.2 RHR Drywell Spray System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR Drywell Spray systems and may also prevent water hammer and pump cavitation.

Selection of RHR Drywell Spray System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

(continued)

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RHR Drywell Spray B 3.6.2.5 BASES (continued)

SURVEILLANCE SR 3.6.2.5.2 (continued)

REQUIREMENTS The RHR Drywell Spray System is OPERABLE when it is sufficiently filled with water. Acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume at the suction or discharge of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Drywell Spray System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water), the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits.

RHR Drywell Spray System locations susceptible to gas accumulation are monitored and, ifgas is found, the gas volume is compared to the acceptance criteria for the location. Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not be practical for locations that are inaccessible due to radiological or environmental conditions, the plant configuration, or personnel safety. For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location. Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

SR 3.6.2.5.3 This surveillance is performed following maintenance which could result in nozzle blockage to verify that the spray nozzles are not obstructed and that flow will be provided when required. The frequency is adequate to detect degradation in performance due to the passive nozzle design and its normally dry state and has been shown to be acceptable through operating experience.

(continued)

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RHR - High Water Level B 3.9.7 BASES LCO reactor coolant temperature in the desired range, valves, piping, (continued) instruments, and controls to ensure an OPERABLE flow path. In MODE 5, the RHR cross tie valve is not required to be closed; thus, the valve may be opened to allow RHR pumps in one loop to discharge through the opposite recirculation loop to make a complete subsystem. In addition, the RHRSW cross tie valves may be open to allow RHRSW pumps in one loop to provide cooling to a heat exchanger in the opposite loop to make a complete subsystem.

Management of gas voids is important to RHR Shutdown Cooling System OPERABILITY.

Additionally, each RHR shutdown cooling subsystem is considered OPERABLE if it can be manually aligned (remote or local) in the shutdown cooling mode for removal of decay heat. Operation (either continuous or intermittent) of one subsystem can maintain and reduce the reactor coolant temperature as required (sufficient to maintain reactor coolant temperature in the desired range). However, to ensure adequate core flow to allow for accurate average reactor coolant temperature monitoring, nearly continuous operation is required. A Note is provided to allow a 2 hour2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months exception to shut down the operating subsystem every 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months .

The LCO consists of two separate requirements. Either requirement can be not met (and the associated Condition entered) without necessarily affecting the other (and without necessarily entering the other associated Condition). For example, an operating RHR shutdown cooling subsystem can be removed from operation, yet remain OPERABLE for the decay heat removal function. (Manual alignment and operation can satisfy OPERABILITY.) Conversely, an RHR shutdown cooling subsystem (or recirculation pump) can remain in operation, circulating reactor coolant; however, if the RHR heat exchanger cannot remove decay heat, the subsystem is inoperable.

The LCO Notes follow this separation of requirements: an exception to circulating reactor coolant (Note 1) does not result in an exception to the OPERABILITY requirement, and an exception to the RHR shutdown cooling subsystem OPERABILITY requirements does not result in an exception to the requirement for circulating reactor coolant (Note 2).

APPLICABILITY One RHR shutdown cooling subsystem must be OPERABLE and in operation in MODE 5, with irradiated fuel in the RPV and the water level Ž 22 ft 1/8 inches above the top of the RPV flange, to provide decay heat removal. RHR shutdown cooling subsystem requirements in other MODES are covered by LCOs in Section 3.4, Reactor Coolant System (RCS). RHR Shutdown Cooling subsystem requirements in MODE 5 with irradiated fuel in the RPV and the water (continued)

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RHR - High Water Level B 3.9.7 BASES ACTIONS B.1, B.2, B.3, and B.4 (continued) isolation capability. The administrative controls can consist of stationing a dedicated operator, who is in continuous communication with the control room, at the controls of the isolation device. In this way, the penetration can be rapidly isolated when a need for secondary containment isolation is indicated.). This may be performed as an administrative check, by examining logs or other information to determine whether the components are out of service for maintenance or other reasons. It is not necessary to perform the Surveillances needed to demonstrate the OPERABILITY of the components. If, however, any required component is inoperable, then it must be restored to OPERABLE status. In this case, a Surveillance may need to be performed to restore the component to OPERABLE status. Actions must continue until all required components are OPERABLE.

C.1 and C.2 If no RHR shutdown cooling subsystem is in operation, an alternate method of coolant circulation is required to be established within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months . The Completion Time is modified such that the 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months is applicable separately for each occurrence involving a loss of coolant circulation.

During the period when the reactor coolant is being circulated by an alternate method (other than by the required RHR shutdown cooling subsystem), the reactor coolant temperature must be periodically monitored to ensure proper functioning of the alternate method. The once per hour Completion Time is deemed appropriate.

SURVEILLANCE SR 3.9.7.1 REQUIREMENTS This Surveillance demonstrates that the required RHR shutdown cooling subsystem is in operation and circulating reactor coolant. The required flow rate is determined by the flow rate necessary to provide sufficient decay heat removal capability. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

SR 3.9.7.2 RHR Shutdown Cooling System piping and components have the potential to develop voids and pockets of entrained gases.

Preventing and managing -gasintrusion and accumulation is necessary for proper operation of the req uired RHR shutdown (continued)

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RHR - High Water Level B 3.9.7 BASES SURVEILLANCE SR 3.9.7.2 (continued)

REQUIREMENTS cooling subsystem(s) and may also prevent water hammer, pump cavitation, and pumping of noncondensible _gas into the reactor vessel.

Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a review of system design information, includinq piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The RHR Shutdown Cooling System is OPERABLE when it is sufficiently filled with water. For the RHR SDC piping on the discharge side of the RHR pump, acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume in the RHR SDC piping on the discharge side of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water),

the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits. Since the RHR SDC piping on the discharge side of the pump is the same as the Low Pressure Coolant Iniection piping, performances of surveillances for ECCS TS may satisfy the requirements of this surveillance. For the RHR SDC piping on the suction side of the RHR pump, the surveillance is met by virtue of the performance of operating procedures that ensure that the RHR SDC suction piping is adequately filled and vented. The performance of these manual actions ensures that the surveillance is met.

RHR SDC System locations on the discharge side of the RHR pump susceptible to gas accumulation are monitored and, ifgas is found, the gas volume is compared to the acceptance criteria for the location.

Susceptible locations in the same system flow path which are subject to the same gas intrusion mechanisms may be verified by monitoring a representative subset of susceptible locations. Monitoring may not (continued)

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RHR - High Water Level B 3.9.7 BASES SURVEILLANCE SR 3.9.7.2 (continued)

REQUIREMENTS be practical for locations that are inaccessible due to radiological or environmental conditions, the plant confiauration. or personnel safety.

For these locations alternative methods (e.g., operating parameters, remote monitoring) may be used to monitor the susceptible location.

Monitoring is not required for susceptible locations where the maximum potential accumulated gas void volume has been evaluated and determined to not challenge system OPERABILITY. The accuracy of the method used for monitoring the susceptible locations and trending of the results should be sufficient to assure system OPERABILITY during the Surveillance interval.

The SR can be met by virtue of having an RHR SDC subsystem in service in accordance with operating procedures.

The Surveillance Frequency is controlled under the Surveillance Frequency Control Program. The Surveillance Frequency may vary by location susceptible to gas accumulation.

REFERENCES 1. 10 CFR 50, Appendix A, GDC 34.

2. Technical Requirements Manual, Section 8.0.

3. NRC NO.93-102, "Final Policy Statement on Technical Specification Improvements," July 23, 1993.

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RHR - Low Water Level B 3.9.8 B 3.9 REFUELING OPERATIONS B 3.9.8 Residual Heat Removal (RHR) - LowWater Level BASES BACKGROUND The purpose of the RHR System in MODE 5 is to remove decay heat and sensible heat from the reactor coolant, as required by GDC 34 (Ref. 1). Each of the two shutdown cooling loops of the RHR System can provide the required decay heat removal. Each loop consists of two motor driven pumps, a heat exchanger, and associated piping and valves. Both loops have a common suction from the same recirculation loop. Each pump discharges the reactor coolant, after it has been cooled by circulation through the respective heat exchangers, to the reactor via the associated recirculation loop. The RHR heat exchangers transfer heat to the RHR Service Water System. The RHR shutdown cooling mode is manually controlled.

APPLICABLE With the unit in MODE 5, the RHR System is not required to SAFETY ANALYSES mitigate any events or accidents evaluated in the safety analyses.

The RHR System is required for removing decay heat to maintain the temperature of the reactor coolant.

The RHR System satisfies Criterion 4 of the NRC Policy Statement (Ref. 3).

LCO In MODE 5 with irradiated fuel in the reactor pressure vessel (RPV) and the water level < 22 ft 1/8 inches above the RPV flange, two RHR shutdown cooling subsystems must be OPERABLE.

An OPERABLE RHR shutdown cooling subsystem consists of an RHR pump and the associated heat exchanger, an RHRSW pump providing cooling to the heat exchanger with sufficient flow to maintain reactor coolant temperature in the desired range, valves, piping, instruments, and controls to ensure an OPERABLE flow path. The two required RHR shutdown cooling subsystems have a common suction source and are allowed to have a common heat exchanger and common discharge piping. Management of gas voids is important to RHR Shutdown Cooling System OPERABILITY.

Since the piping and heat exchangers are passive components that are assumed not to fail, they are allowed to be common to both subsystems. Thus, to meet the LCO, both RHR pumps in one loop or (continued)

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RHR - Low Water Level B 3.9.8 BASES (continued)

SURVEILLANCE SR 3.9.8.1 REQUIREMENTS This Surveillance demonstrates that one required RHR shutdown cooling subsystem is in operation and circulating reactor coolant. The required flow rate is determined by the flow rate necessary to provide sufficient decay heat removal capability. The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.

SR 3.9.8.2 RHR Shutdown Cooling System piping and components have the potential to develop voids and pockets of entrained gases. Preventing and managing gas intrusion and accumulation is necessary for proper operation of the RHR shutdown cooling subsystems and may also prevent water hammer, pump cavitation, and pumping of noncondensible gas into the reactor vessel.

Selection of RHR Shutdown Cooling System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrumentation drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walk downs to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or could otherwise cause gas to be trapped or difficult to remove during system maintenance or restoration.

Susceptible locations depend on plant and system configuration, such as stand-by versus operating conditions.

The RHR Shutdown Cooling System is OPERABLE when it is sufficiently filled with water. For the RHR SDC piping on the discharge side of the RHR pump, acceptance criteria are established for the volume of accumulated gas at susceptible locations. If accumulated gas is discovered that exceeds the acceptance criteria for the susceptible location (or the volume of accumulated gas at one or more susceptible locations exceeds an acceptance criteria for gas volume in the RHR SDC piping on the discharge side of a pump), the Surveillance is not met. If it is determined by subsequent evaluation that the RHR Shutdown Cooling System is not rendered inoperable by the accumulated gas (i.e., the system is sufficiently filled with water),

the Surveillance may be declared met. Accumulated gas should be eliminated or brought within the acceptance criteria limits. Since the RHR SDC piping on the discharge side of the pump is the same as the Low Pressure Coolant Iniection piping, performances of surveillances for ECCS TS may satisfy the requirements of this (continued)

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