RC-15-0113, License Amendment Request LAR-08-001, 62Request to Revise Technical Specifications to Adopt Technical Specifications Task Force (TSTF)-523, Generic Letter 2008-01, Managing Gas Accumulation

License Amendment Request LAR-08-001, 62Request to Revise Technical Specifications to Adopt Technical Specifications Task Force (TSTF)-523, Generic Letter 2008-01, Managing Gas Accumulation

ML15275A089
Person / Time
Site:	Summer
Issue date:	09/29/2015
From:	Gatlin T South Carolina Electric & Gas Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
GL-2008-01, LAR-08-001, RC-15-0113
Download: ML15275A089 (44)

Text

Thomas D. Gatlin Vice President, Nuclear Operations 803.345.4342 A

CANA CMPAN September 29, 2015 RC-15-0113 U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555-0001

Subject:

VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) UNIT 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 LICENSE AMENDMENT REQUEST LAR-08-001 62 REQUEST TO REVISE TECHNICAL SPECIFICATIONS TO ADOPT TECHNICAL SPECIFICATIONS TASK FORCE (TSTF)-523 "GENERIC LETTER 2008-01, MANAGING GAS ACCUMULATION"

References:

1. Letter from Thomas D. Gatlin (SCE&G) to NRC Document Control Desk, "Notification of an Intended Change to a Commitment Date Associated with NRC Generic Letter 2008-01" dated March 5, 2015, (RC-15-0037) [ML15070A534]

2. NRC Generic Letter 2008-01, "Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems" dated January 11, 2008

[ML072910759]

In accordance with the provisions of Section 50.90 of Title 10 of the Code of Federal Regulations, South Carolina Electric & Gas Company (SCE&G), acting for itself and as agent for South Carolina Public Service Authority, requests Nuclear Regulatory Commission (NRC) review and approval to amend Operating License NPF-12 for VCSNS.

The proposed amendment would modify TS requirements to address NRC Generic Letter (GL) 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." VCSNS committed to submit a proposed change under Reference 1. provides a description and assessment of the proposed change. Attachment 2 provides the existing TS pages marked up to show the proposed change. Attachment 3 provides revised (clean) TS pages. Attachment 4 provides existing TS Bases pages marked to show the proposed change. Changes to the existing TS Bases, consistent with the technical and regulatory analyses, will be implemented under the Technical Specification Bases Control Program. They are provided in Attachment 4 for information only.

In accordance with 10 CFR 50.91, a copy of this application, with attachments, is being provided to the designated South Carolina Official.

V. C. Summer Nuclear Station; P.O0.

Box 88.' Jenkinsville, Sc.*

29065.* F (803) 941-9776

¶ Document Control Desk LAR/CR-08-001 62 RC-15-O0113 Page 2 of 2 SCE&G requests approval of the proposed changes within one year, with an implementation

date of 90 days after issuance of amendment, to permit program changes and training.

This proposed change has been reviewed and approved by both the VCSNS Plant Safety Review Committee and the VCSNS Nuclear Safety Review Committee.

This document contains no new commitments.

If you have any questions about this submittal, please contact Mr. Bruce L. Thompson at (803) 931-5042.

I certify under penalty of perjury that the information contained herein is true and correct.

xcu t d on" Thom s

. Gatlin RLPFI-DG/ts Attachments:

I.

Description and Assessment of the Proposed Change II.

TS Pages (Mark-Up)

Ill.

TS Pages (Clean)

IV. TS Bases (Mark-Up)

V.

TS BASES (Clean)

VI.

List of Regulatory Commitments c:

K. B. Marsh S. A. Byrne J. B. Archie N. S. Camns J. H. Hamilton J. W. Williams W. M. Cherry V. M. McCree S. A. Williams K. M. Sutton S. E. Jenkins Paulette Ledbetter NRC Resident Inspector NSRC RTS (LAR/CR-08-001 62)

File (813.20)

PRSF (RC-15-0113)

1[

'0 Document Control Desk LAR/CR-08-001 62 RC-15-O0113 Attachment I Page 1 of 5 VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) Unit 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 Attachment I Description and Assessment of the Proposed Change

Document Control Desk LAR/CR-08-001 62 RC-15-0113 Attachment I Page 2 of 5

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" (Reference 2).

The proposed amendment is consistent with TSTF-523, Revision 2, "Generic. Letter 2008-01, Managing Gas Accumulation."

2.0 ASSESSMENT

2.1 Applicability of Published Safety Evaluation VCSNS has reviewed the model safety evaluation dated January *15, 2014, as part of the Federal Register Notice of Availability. This review included a review of the NRC staff's evaluation, as well as the information provided in TSTF-523. As described in the subsequent paragraphs, Virgil C. Summer Nuclear Station (VCSNS) has concluded that the justifications presented in the TSTF-523 proposal and the model safety evaluation prepared by the NRC staff are applicable to VCSNS Unit 1 and justify this amendment for the incorporation of the changes

• to the VCSNS Technical Specifications (TS).

2.2 Optional Changes and Variations VCSNS 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.

The VCSNS TS utilize different numbering and titles than the Standard Technical Specifications on which TSTF-523 was based. Specifically, the difference in numbering and titles are provided in the table below.

NUREG-1 431 VCSNS Standard Technical Specifications Technical Specifications Westinghouse Plants 3.4.6, RCS LOOPS - Mode 4 3/4.4.1.3 Reactor Coolant System Hot Shutdown 3.4.7, ROS LOOPS.- Mode 5 Loops Filled 3/4.4.1.4.1 Reactor Coolant System Cold

~Shutdown

- Loops Filled 3.4.8, RCS LOOPS - Mode 5 Loops Not Filled 3/4.4.1.4.2 Reactor Coolant System Cold Shutdown-Loops Not Filled 3.5.2, ECCS 3/4.5.2 ECCS - Tava > 3500°F 3.6.6, Containment Spray and Cooling 3/4.6.2.1 Containment Systems Systems Depressurization and Cooling Systems Reactor Building Spray System 3.9.5, RHR and Coolant Circulation - High 3/4.9.7.1 Refueling Operations Residual Heat

Document Control Desk LAR/CR-08-001 62 RC-15-01 13 Attachment I Page 3 of 5 Water Level Removal and Coolant Circulation High Water Level 3.9.6, RHR and Coolant Circulation - Low 3/4.9.7.2 Refueling Operations Low Water Water Level Level These differences are administrative and do not affect the applicability of TSTF-523 to the VCSNS TS.

3.0 REGULATORY ANALYSIS

No Significant Hazards Consideration Determination VCSNS 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 VCSNS technical specifications (TS). 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.

VCSNS has evaluated whether or not a significant hazards consideration is involved with the proposed amendment 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 Reactor Cooling System (RCS), Residual Heat Removal (RHR) and Reactor Building (RB) Spray 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 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, RCS, RHR and RB Spray System are not rendered inoperable due to accumulated gas and to

Document Control Desk LAR/CR-08-001 62 RC-15-01 13 Attachment I Page 4 of 5 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, RCS, RHR and RB Spray 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, VCSNS 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 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 CER 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed change.

Document Control Desk LAR/CR-08-001 62 RC-15-01 13 Attachment I Page 5 of 5 5.0 PRECEDENTS

1. Seabrook Station Letter LAR-14-01, "Application to Revise Technical Specifications to

.Adopt Technical Specifications Task Force (TSTF) Traveler-523 "Generic Letter 2008-01, Managing Gas Accumulation," Using the Consolidated Line Item Improvement Process" dated June 24, 2014 [ML14177A503]

VCSNS follows the Seabrook Station Letter LAR 14-01.

TS changes are similar with the exception section numbering and a few wording differences.

Document Control Desk LAR/CR-08-001 62 RC-15-01 13 Attachment II Page 1 of 8 VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) Unit 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 Attachment II TS Pages (Mark-Up)

REACTOR COOLANT SYSTEM SURVEILLANCE REQIJIRENENTS 4.4.1.3.1> The required Reactor Coolant pump(s), if not in op~eration, shall be determined OPERABI.E..qpce, per 7 days by verifyingoretreerainns and i ndicated power availiabil1ity.

9..r.c.breakr.alinment 4.4.1.3.2 The required steam generator(s) shall be determined OPERABLE by verifying secondary side water level to be greater than or equal to 10% of wide range indication at least once per. 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

4.4.1.3.3 At least one Reactor Coolant or RUR loop shall be verified to be in operation and circulating reactor coolant at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

Not required to be performed until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after entering MODE 4.

SUMNER -

UNIT 1

/ -

mnmn 3/4 4-4

[Amendment[

REACTOR COOLANT SYSTEM COLD SUTDOW -

LOOPS FILLED LIMITING CONDITION FOR OPERATION 3.4.1.4.1I At least one residual heat removal (RHR) loop shall andin operationt, and either:

a.

One additional RHR loop shall be OPERASLE?,

or

b.

The secondary side water level of at least two generators shall be greater than 10 percent of

• indication.

be OPERABLE J steam wide range APPLICABILITY:

ACTION:

MODE S with Reactor Coolant loops filled.r

a.

With less than the above required loops OPERABLE and/or with less than the required steam generator level, iediately initiate corrective, action to return the required loops to OPERABLE status or to restore the required level as soon as possible.

b.

With no residual heat removal loop-in operation, suspend all operations involving a reduction in boron concen-tration of the Reactor Coolant System and immdiately initiate corrective action to return the required residual heat removal loop to operation.

SURVEILLANCE REQUIREMENTS 4.4.1.4.1.1 The secondary side water level of at least two steam generators when required shall be determined to be within limits at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

4.4.1.4.1.2 At least one RHR loop shall be determined to be in operation and circulating reactor coolant.at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

O~ne residual heat removal loop may be inoperable for up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for surveillance testing provided the other RNR loop is OPERABLE and in operation.

• fAReactor Coolant pump shall not be started with one or more of the Re Coolant System cold leg temperatures less than or equal to 300°F unles:

1 m) the pressurizer water voluae is. less than 1288.cubic-feet and/or 2) secondary water temperature of each" steam generator is less than 500 F each of the Reactor Coolant System cold leg temperatures.

• The RHR pump maybe de-energized for up to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> provided 1) no opera are permitted that would cause dilution of the Reactor Coolant System concentration, and 2) core outlet temperature is maintained at least 1I below saturation temperature.

eSUMMIER UNIT 1 3/4 4-S

-Amendment No 4.4.1.4.1.3 Verify RHR loop locations susceptible to gas accumulation are sufficiently filled with water at least once per 31 days.

actor 5the above tions boron-O0 F

.- i-9

0)

COLD SNUTD~ -

LOOPS NOT FILLED

_LIMITING-CONDITION. FOR OPERATION.*

3.4.1,4.2 Two residual heat' removal (RHR) loops shall be'OPERABLEj and. at least one RHR loop shall be in operatiton. t APPLICABILITY:

MODE 5 wit.h Reactor Coolant, loops not filledl.

ACTION:

a.

With less than thle above required loops OPERABLE, inuediate1y initiate corrective action to return the required loops to OPERABLE status as soon as possible.

b.

With no RHR loop In operatiton, suspend all operat'ions involving a reduction in boron concentration of the Reactor Coolant System and tlediatuly inititee corrective actiton to return t~he required RHR loop t~o operati'on.

SURVEI LLANCE REQUIREMENTS_

4.4.1.4.2.1 At, least ant RHR loop shall be det~ermned to be in operation arid circulating reactor coolant at, least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

• _4.4.1.4.2.2 Verify RHR ioop locations susceptible to gas accumulation are "sufficiently filled with water at least once per 31 days.

C ene RHR loop-lmay be inoperale~t for up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for surve'ill'ance testing provided the* other WIR loop is OPERABLE and in operation.

xThe RHR pu.~may be dc-energized for up to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> providled 1) no operations are.permitted that would cause dilution of the Reactor Coolant Systes boron concentration, and 2) core outlet teiperature is maintained at least 100F below saturati on temperature.

SUJI~iR

-UNIT 1

3/4 4-6 JAmendmentI

2. Verify ECCS locations susceptible to gas accumulation are sufficiently filled with water.

,EM*.E.RGENCY CORE COOLING SYSTEMS S URVEiL..ANCE REQUIREMEFNTS 4.5.2 Each ECOS subsystem shall be demonstrated OPERABLE.:

a.

---At least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by verifying that the, folowing valves are in the indicated positons with power to the valve operators removed:

1; 3.

4-5.

6.

7-8.

9-10.

11.

12.

Valve Numnber 8BS6 8B886 8B888A 8889 8701A B701B 8702A 87O2B3 Bi133A 8133B 8108 Valve Function" HHSI kiot Leg injection HHSI Hot Leg Injection ULHSI Cold Leg Injection LHSI Cold Leg Injection LHSI Hot Leg Injection RHR inlet RH-R Inlet RH-R Inlet RHR inlet ChargingIHHSI Cross-Connect ChtargingIHHSI Cwoss-Connect Charging Mini-Row Header Isoati~on Valve Position Closed Closed Open Open Closed Closed Closed Closed Closed Open Open Open

b.

At least once per 31days by:

1.

Verifying that each valve (manual, power operated or automatic) in the flow path that is not ioclk.hald, or otherwise secured in position, is in its correct positibt: 3z*

2.

Ve1-fvin tha th ECC r~ia o

1 _ 4 _.vs..i.

J.- ECC I-*-~-

L--.t i -

L

=.

• pump cacin~ ano arcesciote ocamrgo ppmg nign point.

c.

By a visual inspeclon which verifies ti-at no loose debris (rags, trash, clothing, etc.) is present in the reactor building which could be transported to the RI-R and Spray Recirculation sumps and cause restrction of the pump suctions during LOCA conditions. This visual inspection shall be performed:

1.

For all accessible areas of the reactor building prior to establishing CONTAINMENT INTEGRITY, and

2.

01 the areas affected within the reactor building at the completion of each reactor building entry when CONTAINMENT INTEGRITY is established.

d.

At least once per 18 months by:;

1..

Verifying automatic interlock action of the RI-R system from the Reactor Coolant System by ensuring that, with a simulated or a*ctual Reactor Coolant System pressure signal greater than or equal to 425 psig, the interlocks prevent the valves from being opened.

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

I SUMMER - UNIT 1 3/4 5-4 Amendment No. eg.,

a. At least once per 31 days by:

1. Verifying that each valve (manual, power operated, or automatic) in the flow path that is not locked, sealed or otherwise secured in position is in its correct position*, and

2. Verifying Containment Spray locations susceptible to gas accumulation are

[sutticiently tilled with water.*"

CONTAINMENT SYSTEMS 3/4.6.2 DEFRESSUXIZATION A1ND COOLING SYSTEMS REACTOR BUILDING SPRAY S.YS.TE.M" LIMITINqG CONDITION FOR OPERATION 3.6.2.1 Two independent reactor buildiing spray systems shaflbe OPERABLE with each spray system capable of taking suction from the RWST and autbmaticafly transferring saction to the spray sump.

APPUICABLITY: MODES 1, 2, 3, and 4.

ACTION:

With one reactor building spray system inoperable, restore the inoperable spray system to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANDBY within the nestS6 hours; restore the inoperable spray system to OPERABLE status within the nest 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or be in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

SURVEILLANCE REQUIREMENTS 4.6.2.1 Each reactor building spray system shall be demonstrated OPERABLE:

a.

At IeazA. once per 31 dayi by verifying that. each valve (manual,

b.

By verifying, that on recircuiation flow, each pump develops a discharge pressure of greater than or equal to 195 psig when tested pursuant to Specification 4.0.5.

c.

At least once per 18 months during shutdown, br.

1.

Verifying that each automatic valve in the flow path actuates to its correct position on each of the following test signals a Phase 'A', Reactor Buildinag Spray Actuation, and Containment Sump Recirculation.

2.

Verifying that each spray pump starts automatically on a Reactor Building Spray Actuaation test signal.

d.

At least once per 10 years by performing an air or smoke or equivalent flow test throujh each spray header and verifying each spray nozzle.

is umobstruced w_.I*Not required to be met for system vent flow paths opened under

[

administrative control SUMMER -UNIT 1 3/4 6-12 SlIMER UNT 1 /4 -12Amendment No.

mq

~REFUELING OPERATIONS

_3/4.9.7 RESIDUAL KEAT REMOVAL AND COOLANT CIRCULATION HIGH WATER LEVEL LIMITING CONDITION FOR OPERATION 3.9.7.1.,. At least one residual. heat removal (RIIR) loop shall be OPERABLE arnd i n operati on. 2 APPLICABILITYf:

MODE 6 when the water -level above the top of the reactor pressure vessei'flatnge is greater than or equal.to.23-eet.

ACTION:

With no residual heat removal loop OPERABLE and in operation, suspend all operations involving an increase in the reactor decay heat load or a reduction in boron concentration of the Reactor Coolant System and innediately initiate corrective action to return the required RHR loop t:o OPERABLE and operating status as soon as possible.

Close all containment penetrations providing direct access from the containment atm~osphere, to the outside atmosphere within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

0 SURVEILLANCE REQUIREMENTS 4.9.7.1'At least one residual heat removal loop shall be verified to be in operation and circulating reactor coolant at a flow rate of greater than or equal to 2800 gpu at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

k j4.9.7. 1.2 Verify required RHR ioop locations susceptible to gas accumulation are Isufficiently filled with water at least once per 31 days.

The residual heat removal loop may be removed from operation for up to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> per 8-hour period during thte performance of CORE ALTERATIONS in the "vicinity of the reactor pressure vessel hot legs.

SSUMM4ER

- UNIT 2.

3/4 9-7 IAmendment No.

REFUELING OPERATIONS LOW WATER LEVEL LIMITING CONDITION FOR OPERATION 3.9.7.2 Two independent Residual Heat Removal (RIIR) loops shall be OPERABLE, and at lea~st one RIR loop shall be in operation°t APPLICABILITY:

MOUE.,.6...hen *the water. level., above the top*.of the* reactor pressure vessel flange is less than 23 feet.-

ACTION:

a. With less than the required. RHR.-loops.-OPERABLE; immediately initiate corrective action to return the required RHR loops to OPERABLE status or to establish greater than or equal to 23 feet of water above the reactor pressure

]apaatshooq.sn as possible.

• --vesselI

b.

With no RJIR loop in operation, IU*~

all operations involving a reduction in boron concentration of the Reactor Coolant System and

.immediately initiate corrective action to return the required RIIR loop to operation.

Close all containment penetrations providing direct access from the containment atmosphere to the outside atmosphere within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

SURVEILLANCE REQUIREMENTS 4.9.7.2 At lleast one residual heat removal loop shall be verified in operation

• and circulating reactor coolant at a flow rate of greater than or equal to 2800 gpm at least once per 1Z hours.

ALTERATIONS' in the vicinity of the reactor pressure vessel hot legs.

SUMM4ER -

UNIT 1 3/4 9-8 IAmendment No.

i

Document Control Desk LAR/CR-08-00 162 RC-15-01 13 Attachment III Page 1 of 8 VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) Unit 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 Attachment III TS Pages (Clean)

Remove Pages Insert Pages

______TS Page 3/4-4-4 TS Page 3/4-4-4 TS Page 3/4-4-5 TS Page 3/4-4-5 TS Page 3/4-4-6 TS Page 3/4-4-6

.TS Page 3/4-5-4 TS Page 3/4-5-4 TS Page 3/4-6-12 TS Page 3/4-6-12 TS Page 3/4-9-7 TS Page 3/4-9-7 TS Page 3/4-9-8 TS Page 3/4-9-8

REACTOR COOLANT SYSTEM SURVEILLANCE REQUIREMENTS 4.4.1.3.1 The required Reactor Coolant pump(s), if not in operation, shall be determined OPERABLE once per 7 days by verifying correct breaker alignments and indicated power availability.

4.4.1.3.2 The required steam generator(s) shall be determined OPERABLE by verifying secondary side water level to be greater than or equal to 10% of wide range indication at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

4.4.1.3.3 At least one Reactor Coolant or RHR loop shall be verified to be in operation and circulating reactor coolant at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

4.4.1.3.4 Verify RHR loop locations susceptible to gas accumulation are sufficiently filled with water at least once per 31 days.*

• Not required to be performed until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after entering MODE 4.

SUMMER - UNIT 1

/

mnmn 3/4 4-4 Amendment

REACTOR COOLANT SYSTEM COLD SHUTDOWN - LOOPS FILLED LIMITING CONDITION FOR OPERATION 3.4.1.4.1 At least one residual heat removal (RHR) loop shall be OPERABLE and in operation*, and either:

a.

One additional RHR loop shall be OPERABLE#' or

b.

The secondary side water level of at least two steam generators shall be greater than 10 percent of wide range indication.

APPLICABILITY:

MODE 5 with Reactor Coolant loops filled##

ACTION:

a.

With less than the above required loops OPERABLE and/or with less than the required steam generator level, immediately initiate corrective action to return the required loops to OPERABLE status or to restore the required level as soon as possible.

b.

With no residual heat removal loop in operation, suspend all operations involving a reduction in boron concentration of the Reactor Coolant System and immediately initiate corrective action to return the required residual heat removal loop to operation.

SURVEILLANCE REQUIREMENTS 4.4.1.4.1.1 The secondary side water level of at least two steam generators when required shall be determined to be within limits at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

4.4.1.4.1.2 At least one RHR loop shall be determined to be in operation and circulating reactor coolant at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

4.4.1.4.1.3 Verify RHR loop locations susceptible to gas accumulation are sufficiently filled with water at least once per 31 days.

One residual heat removal loop may be inoperable for up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for surveillance testing provided the other RHR loop is OPERABLE and in operation.

1. 1. t A Reactor Coolant pump shall not be started with one or more of the Reactor Coolant System cold leg temperatures less than or equal to 300°F unless 1) the pressurizer water volume is less than 1288 cubic feet and/or 2) the secondary water temperature of each steam generator is less than 50°F above each of the Reactor Coolant System cold leg temperatures.

• The RHR pump may be de-energized for up to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> provided 1) no operations are permitted that would cause dilution of the Reactor Coolant System boron concentration, and 2) core outlet temperature is maintained at least 1 00F below saturation temperature.

SUMMER - UNIT 1

/

mnmn 19 3/4 4-5 Amendment

REACTOR COOLANT SYSTEM COLD SHUTDOWN - LOOPS NOT FILLED LIMITING CONDITION FOR OPERATION 3.4.1.4.2 Two residual heat removal (RHR) loops shall be OPERABLE# and at least one RHR loop shall be in operation.*

APPLI CABI LITY:

MODE 5 with Reactor Coolant loops not filled.

ACTION:

a.

With less than the above required loops OPERABLE, immediately initiate corrective action to return the required loops to OPERABLE status as soon as possible.

b.

With no RHR loop in operation, suspend all operations involving a reduction in boron concentration of the Reactor Coolant System and immediately initiate corrective action to return the required RHR loop to operation.

SURVEILLANCE REQUIREMENTS 4.4.1.4.2.1 At least one RHR loop shall be determined to be in operation and circulating reactor coolant at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

4.4.1.4.2.2 Verify RHR loop locations susceptible to gas accumulation are sufficiently filled with water at least once per 31 days.

One RHR loop may be inoperable for up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for surveillance testing provided the other RHR loop is OPERABLE and in operation.

• The RHR pump may be de-energized for up to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> provided 1) no operations are permitted that would cause dilution of the Reactor Coolant System boron concentration, and 2) core outlet temperature is maintained at least 1 0°F below saturation temperature.

SUMMER - UNIT 1

/

mnmn 3/4 4-6 Amendment

EMERGENCY CORE COOLING SYSTEMS SURVEILLANCE REQUIREMENTS 4.5.2 Each ECCS subsystem shall be demonstrated OPERABLE:

a.

At least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by verifying that the following valves are in the indicated positions with power to the valve operators removed:

1.2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

Valve Number 8884 8886 8888A 8888B 8889 8701A 8701B 8702A 8702B 8133A 8133B 8106 Valve Function HHSI Hot Leg Injection HHSI Hot Leg Injection LHSI Cold Leg Injection LHSI Cold Leg Injection LHSI Hot Leg Injection RHR Inlet RHR Inlet RHR Inlet RHR Inlet Charging/HHSI Cross-Connect Charging/HHSI Cross-Connect Charging Mini-Flow Header Isolation Valve Position Closed Closed Open Open Closed Closed Closed Closed Closed Open Open Open

b.

At least once per 31 days by:

1.

Verifying that each valve (manual, power operated or automatic) in the.

flow path that is not locked, sealed, or otherwise secured in position, is in its correct position*, and

2.

Verify ECCS locations susceptible to gas accumulation are sufficiently filled with water.

c.

By a visual inspection which verifies that no loose debris (rags, trash, clothing, etc.) is present in the reactor building which could be transported to the RHR and Spray Recirculation sumps and cause restriction of the pump suctions during LOCA conditions. This visual inspection shall be performed:

1.

For all accessible areas of the reactor building prior to establishing CONTAINMENT INTEGRITY, anid

2.

Of the areas affected with the reactor building at the completion of each reactor building entry when CONTAINMENT INTEGRITY is established.

• d.

At least once per 18 months by:

1.

Verifying automatic interlock action of the RHR system from the Reactor Coolant System by ensuring that, with a simulated or actual Reactor Coolant System pressure signal greater than or equal to 425 psig, the interlocks prevent the valves from being opened.

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

SUMMER-UNIT 1 3/4 5-4 SUMMR

- NIT 3/45-4Amendment No. 89 --

,423 6,

CONTAINMENT SYSTEMS 3/4.6.2 DEPRESSURIZATION AND COOLING SYSTEMS REACTOR BUILDING SPRAY SYSTEM LIMITING CONDITION FOR OPERATION 3.6.2.1 Two independent reactor building spray systems shall be OPERABLE with each spray system capable of taking suction from the RWST and automatically transferring suction to the spray sump.

APPLICABILITY:

MODES 1, 2, 3, and 4.

ACTION:

With one reactor building spray system inoperable, restore the inoperable spray system to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />; restore the inoperable spray system to OPERABLE status within the next 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> or be in COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.

SURVEILLANCE REQUIREMENTS 4.6.2.1 Each reactor building spray system shall be demonstrated OPERABLE:

a.

"At least once per 31 days by:

1. Verifying that each valve (manual, power operated, or automatic) in the flow path that is not locked, sealed or otherwise secured in position is in its correct position**, and

2. Verifying Containment Spray locations susceptible to gas accumulation are sufficiently filled with water.

b.

By verifying, that on recirculation flow, each pump develops a discharge pressure of greater than or equal to 195 psig when tested pursuant to Specification 4.0.5.

c.

At least once per 18 months during shutdown, by:

1. Verifying that each automatic valve in the flow path actuates to its correct position on each of the following test signals a Phase 'A', Reactor Building Spray Actuation, and Containment Sump Recirculation.

2. Verifying that each spray pump starts automatically on a Reactor Building Spray Actuation test signal.

d.

At least once per 10 years by performing an air or smoke or equivalent flow test through each spray header and verifying each spray nozzle is unobstructed.

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

SUMMER-UNIT 1 3/4 6-12 SUMMER-UNI I 3/ 6-12Amendment No.

2

REFUELING OPERATIONS 3/4.9.7 RESIDUAL HEAT REMOVAL AND COOLANT CIRCULATION HIGH WATER LEVEL LIMITING CONDITION FOR OPERATION 3.9.7.1 At least one residual heat removal (RHR) loop shall be OPERABLE and in operation.*

APPLICABILITY:

MODE 6 when the water level above the top of the reactor pressure vessel flange is greater than or equal to 23 feet.

ACTION:

With no residual heat removal loop OPERABLE and in operation, suspend all operations involving an increase in the reactor decay heat load or a reduction in boron concentration of the Reactor Coolant System and immediately initiate corrective action to return the required RHR loop to OPERABLE and operating status as soon as possible.. Close all containment penetrations providing direct access from the containment atmosphere to the outside atmosphere within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

SURVEILLANCE REQUIREMENTS 4.9.7.1.1 At least one residual heat removal loop shall be verified to be in operation and circulating reactor coolant at a flow rate of greater than or equal to 2800 gpm at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

4.9.7..1.2 Verify required RHR loop locations susceptible to gas accumulation are sufficiently filled with water at least once per 31 days.

The residual heat removal loop may be removed from operation for up to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> per 8-hour period during the performance of CORE ALTERATIONS in the: vicinity of the reactor pressure vessel hot legs.

SUMMER - UNIT 1

/

mnmn o

314 9-7 Amendment No.

REFUELING OPERATIONS LOW WATER LEVEL LIMITING CONDITION FOR OPERATION 3.9.7.2 Two independent Residual Heat Removal (RHR) loops shall be OPERABLE, and at least one RHR loop shall be in operation.*

APPLICABILITY:

MODE 6 when the water level above the top of the reactor pressure vessel flange is less than 23 feet.

ACTION:

a.

With less than the required RHR loops OPERABLE, immediately initiate corrective action to return the required RHR loops to OPERABLE status or to establish greater than or equal to 23 feet of water above the reactor pressure vessel flange, as soon as possible.

b.

With no RHR loop in operation, suspend all operations involving a reduction in boron concentration of the Reactor Coolant System and immediately initiate corrective action to return the required RHR loop to operation. Close all containment penetrations providing direct access from the containment atmosphere to the outside atmosphere within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

SURVEILLANCE REQUIREMENTS 4.9.7.2.1 At least one residual heat removal loop shall be verified in operation and circulating reactor coolant at a flow rate of greater than or equal to 2800 gpm at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

4.9.7.2.2 Verify required RHR loop locations susceptible to gas accumulation are sufficiently filled with water at least once per 31 days.

• • Prior to initial criticality the residual heat removal loop may be removed from operation for up to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> per 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> period during the performance of CORE ALTERATIONS in the vicinity of the reactor pressure vessel hot legs.

SUMMER - UNIT 13/9-AmnetNo 3/4 9-8 Amendment No.

Document Control Desk LAR/CR-08-001 62 RC-15-01 13 Attachment IV Page 1 of 10 VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) Unit 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 Attachment IV TS Bases (Mark-Up)

3/4.4 REACTOR COOLANT SYSTEM I

BASES 3/4.4.1 REACTOR COOLANT LOOPS AND COOLANT CIRCULATION The plant is designed to operate with all reactor coolant loops in operation, and maintain DNBR in the core at or above the design limit during all normal operations and anticipated transients.

In MODES 1 and 2 with one reactor coolant loop not in operation this specification requires that the plant be in at least HOT STANDBY within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />.

In MODE 3, a single reactor coolant loop provides sufficient heat removal capability for removing decay heat; however, single failure considerations require that two loops be OPERABLE.

In MODE 4, and in MODE 5 with reactor coolant loops filled, a single reactor coolant loop or RHR loop provides sufficient heat removal capability for removing decay heat; but single failure considerations require that at least two loops (either RHR or RCS) be OPERABLE.

In MODE 5 with reactor coolant loops not filled, a single RHR loop provides

sufficient heat removal capability for removing decay heat; but single failure considerations,*and the unavailability of the steam generators as a heat

.removing component,. require that at least two RHR loops be OPERABLE.

The operation of one Reactor Coolant Pump or one RHR pupprovides adequate S flow to ensure mixing, prevent stratification and produce gradual reactivity changes during boron concentration reductions in the Reactor Coolant System.

The' reactivity change rate associated with boron reduction will, therefore, be within the capability of operator recognition and control.

The restrictions on starting a Reactor Coolant Pump with one or more RCS. cold legs less than or equal to 3000F are provided to prevent RCS pressure transients, caused by energy additions from the secondary system, which could exceed the limits of Appendix G to 10 CFR Part 50.

The RCS will be protected against overpressure transients and will not exceed the limits of Appendix G by either (1) restricting the water volume in the pressurizer and thereby providing a volume for the primary coolant to expand into, or (2) by restricting starting of the RCPs to when the secondary water temperature of each steam generator is less than 500F above each of the RCS cold leg temperatures.

~Insert 1I Management of gas voids is important to RHR System

0)

OPERABILITY.

I.

SUMMER -

UNIT 1 B 3/4 4-1 Amendment No.

Insert 1 REACTOR COOLANT LOOPS AND COOLANT CIRCULATION (Continued)

RHiR 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 RIHR

• loops and may also prevent water hanuner, pump cavitation, and pumping of non-condensable gas into the reactor vessel.

Selection of RIHR System~locations susceptible to gas accumulation is based on a review of system design information, including piping and instrument drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walkdowns to validate the system high points and to confirm the location and orientation of important components that can become sources of gas or couldotherwise cause gas to be trapped or difficult to remove during system maintenance or restoration. Susceptible locations depend on plant and system configuration, such as standby versus operating conditions.

The RHIR 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 RHIR 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.

RHiR 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 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, 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.

Surveillance Requirement 4.4.1.3.4 is modified by a Note that states the Surveillance Requirement is not required to be performed until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after entering MODE 4. In a rapid shutdown, there may be insufficient time to verify, all susceptible locations prior to entering MODE 4.

The 31 day frequency for ensuring locations are sufficiently filled with water takes into consideration the gradual nature of gas accumulation in the RHIR System piping and the procedural controls governing system operation.

314. 5 EMERGENCY CORE COOLING SYSTEMS BASES 314.5.1 ACCUMULATORS aThe :OPERABILITY of each Reactor Coolant System (RCS) accumu~lator ensureg that asufficient volume of borated water will be immediately *forced into the reactor core through each of the cold legs in the event the RCS pressure falls below the pressure of. the,.accuimulators..

This initial surge..of wkter into the core provides the initial cooling mechanism during large RCS ri'Pe"tuptures..

in addition, the borated water serves to limit the maximum power which may be reached during large secondary pipe ruptures.

The limits on accumulator volume, boron concentration and pressure ensure

.that the assumptions used for accumulator injection in the safety analysis are met.

The accumulator power operated isolation valves are considered to be

" operating bypasses" in the context of IEEE Std. 279-1971, which requires that

• bypasses. of a protective.functidn be removed automatically whenever permissive conditions are not met.. In additton, las these* accumulator isolation valves

• fail to meet single failure criteria, removal of power to the valves is required.

The limits for operation with an accumul'ator inoperable for any reason except an isolation valve closed minimizes the time exposure of the plant to a LOCA event occurring concurrent with failure of an additional accumulator which may result in unacceptable peak cladding temperatures.

If a closed isolation valve cannot be immediately opened, the full capability of one accumulator is not available and prompt action is required to place the reactor in a mode where this capability is not required.

3/4.5.2 and 3/4.5.3 EMERGENCY CORE COOLING SYSTEM (ECCS)

SUBSYSTEMS The OPERABILITY of two independent ECCS subsystems ensures that sufficient emergency core cooling capability will be available in the event of a LOCA assuming the loss of one subsystem through any single failure consideration.

Either subsystem operating in conjunction with the accumulators is capable of supplying sufficient core cooling to limit the peak cladding temperatures within acceptable limits for all postulated break sizes ranging from the double ended break of the largest RCS cold leg pipe downward.

In addition, each ECCS subsystem provides long term core cooling capability in the

• recirculation mode during the accident recovery period.

With the RCS temperature below 3500 F, one OPERABLE ECCS subsystem is, acceptable without single failure consideration on the basis of the stable*

reactivity condition of the reactor and the limited core cooling requirements..

IECOS OPERABILITY.

SUMMER-UNIT I B 3/4 5-1 SUMME

- UIT 1.B 3/ 5-1Amendment No. ?

EMERGENCY CORE COOLING SYSTEMS BASES ECCS SUBSYSTEMS (Continued)

'The limitation f or a maximum of one centrifugal charging pump to be" OPERABL.E and the Surveillance Requirement to verify, all charging pumps except the reqitired OPERABLE charging pump to be inoperable below 300°F provides-assurance that.a'euas..

ddition pressure transient can be relieved by the operation of a single RHR' suctioii relitf valveo T

The Surveillance Requirements provided to ensure OPERABILITY of each component ensures that at 'a minimum, the assumptions used in the safety analyses are met and that subsystem OPERABILITY is maintained.

Surveillance requirements for throttle valve position stops and flow balance testing provide assurance that proper ECES f~lows will be maintained in the event of a LOCA.

Maintenance of proper flow resistance.and pressure drop in the piping system to each injection point is necessary to:

(1) prevent total pump flow from exceeding runout conditions when the system is in its minimum resistance configuration, (2) provide the proper flow split between injection points In accordance with the assumptions used. in the ECCS-L.OCA analyses, and (3) provide en acceptable.

level of total.ECCS flow to all injection points equal to or above that assumed in.the ECCS-LOCA analyses.

IISET a

3/4.5.4 REFUELING WATLER STORAGE TANK-The OPERABILITY of the Refueling Water Storage Tank (RUST) as part of the ECCS ensures that a sufficient supply of borated water is available for injection by the ECOS in the event of either a LOCAL, a steamline break or inadvertent RCS depressurization.

The limits of RU*ST minluam volume and boron concentration ensure 1) that sufficient water is available within contaitnent to permit re-circulation cooling flow to the core; 2) that the reactor will remain subcrltl-cal in the cold condition (68 to 212 degrees-F) following a small break LOCA assuming complete mixing of the RUST, RCS, Spray Additive Tank (SAT), contain-ment spray system piping and ECCS water volumes with all control rods inserted except the roost reactive control rod assembly (ARI-1), 3) that the reactor will remain subcritical in the cold condition following a large break LOCA (break flow area >3.0 sq. ft.) assuming complete mixing of the RUST, RCS, ECCS water and other sources of water that may eventually reside in the sump post-LOCA with all control rods assumed to be out (ARO),

4) long term subcrlticality fol-

• lowing a steamline break assuming ARI-1 and preclude fuel failure.

->The maximumn allowable value for the RWST boron concentration forms the basis for determining the time (Post-LOCA) at which operator action is required to switch over the ECCS to hot leg recirculation in order to avoid precipitation of the soluble boron.

The contained water volume limit includes an allowance for water not usable because of tank discharge line location or other physical characteristics]

0 SWIMER -

UHIT 1 B 314 5-2 Amendment No, 4/*6/

'.4

INSERT 2 ECCS SUBSYSTEMS (Continued)

ECCS 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 ECCS and may also prevent a water hammer, pump cavitation, and pumping of non-condensable gas into the reactor vessel..

Selection of ECCS locations susceptible to gas accumulation is based on a review of system design information, including piping and instrument drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walkdowns 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 standby versus operating conditions.

The ECCS 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 evaluationthat the ECCS is not rendered*

inoperable by the accumulatedgas (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.

EGGS 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 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, 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 riot 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.

Surveillance Requirement 4.5.2.b. 1) 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 at the system vent path who is in continuous communication with the operators in the control room. The individual will have a method to rapidly close the system vent flow path if directed.

The 31 day frequency for Surveillance Requirement 4.5.2.b.2) takes into consideration the gradual nature of gas accumulation in the ECCS piping and the procedural controls governing system operation.

CONTAIYMENT SYSTEMS BASES 3 14.6.1.7 REACTOR BUILDING VENTILATION SYSTEM The 36-inch conta~inment purge supply and exhaust isolation valves are.

required to be closed during plant operation since these valves have not been demonstrated capable of closing during a LOCAL or steam line break accident.

Maintaini*.,these:,valves closed during plant operations eb~ires that excessive quantities of radioactive materials will not be releasedvia~te containment purge system. To provide assurance that the 36-inch valves cannot be inadvert-ently opened, they are sealed closed in accordance with the Standard Review Plan 6.2.4 which includes mechanical devices to seal or lock the valve closed, or prevent power from being supplied to the valve operator.

The use of the containment purge lines is restricted to the 6 inch purge supply and exhaust isolation valves since unlike the 36 inch valves the 6 inch valves will close during a LOCA or steam line break accident and therefore the site boundary dose guidelines of 10 0TR 100 would not be exceeded in the event of an accident during purging operations."

Periodic leakage integrity tests for purge supply and exhaust isolation"

• valves with resilient material seals will be performed in accordance with the I

Containment Leakage Rate Testing Program.

3/4.6.2. DEPRESSURIZATION AND COOLING SYSTEMS 3/4.6.2.1 REACTOR BUILDING SPRAY SYSTEM The OPERABIITY of the reactor building spray system ensures that reactor building depresurztion and cooling capability will be available in the event of a steam line break. The pressut'e reduction and resultant lower containment leakage rate are consistent with the assumptions used in the accident analyses.

The reactor building spray system and the reactor building cooling, system are redundant to each other in providing post accident cooling of the reactor building atmosphere. However, the reactor building spray system also provides a mechanism for removing iodine from the reactor building atmosphere, and therefore the time requirements for restoring an inoperable spray system to OPERABLE status have been maintained consistent with that assigned other inoperable ESF equipment.L-.

Management of gas

/

voids is important to

/

Containment Spray l

System OPERABILITY.

lINSERT 3

SUMMER - UNIT I B 3/4 6-3 AmendmentNo. 9 INSERT 3 REACTOR BUILDING SPRAY SYSTEM (Continued)

Containment Spray System flow path 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 containment spray trains and may also prevent a water hammer and pump cavitation.

Selection of Containment Spray System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrument drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walkdowns 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 standby versus operating conditions.

• The Containment 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 discoveredthat 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 Containment 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.

Containment 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 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, plant conffiguration, or personnel safety. For these locations, altemnative 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 31 day frequency for Surveillance Requirement 4.6.2.1.a. 1) takes into consideration the gradual nature of gas accumulation in the Containment Spray System piping and the procedural controls governing system operation.

Surveillance Requirement 4.6.2.1.a. 1) 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 at the system vent path who is in continuous communication with the operators in the control room. The individual will have a method to rapidly close the system vent flow path if directed.

REFUELING OPERATIONS BASES 3/4.9.6 MANIPULATOR CRANE The-OPERABILITY requirements for the manipulator cranes ensure that:

" :1) manipulator cranes will be used for movement of control rods and fuel assemblies,,

.. *2) each crane has sufficient load capacity to lift a control rod and fuel assembly, and.

• ' 3) the core internals and pressure vessel are protected from excessive lifting force in the

• event they are inadvertently engaged during lifting operations.

3/4.9.7 RESIDUAL HEAT REMOVAL AND COOLANT.CIRCULATION The requirement that at least one residual heat. removal loop be in operation ensures that 1).sufficient cooling capacity is available to remove decay heat and maintain the water in the reactor pressure vessel below 140°F as required during the REFUELING MODE, and S, 2) sufficient coolant circulation is maintained through the reactor core to minimize the effects I

of a boron dilution incident and prevent boron stratification.

.The requirement to have two RHR loops OPERABLE when there is less than 23 feet of water above the reactor pressure vessel flange ensures that a single failure of the.

.operating RHR loop will not result in a complete loss of residual heat~removal capability.

....-With the reactor vessel head removed and at least 23 feet. of water above the reactor pressure vessel flange, a large heat sink is available for core cooling. Thus, in the event of a "failure of the operating RHR loop, adequate time is provided to initiate emergency procedures to cool the core.

• ~INSERT 41 3/4.9.8 DELETED BY AMENDMENT 183 3/4.9.9 WATER LEVEL - REACTOR VESSEL The restrictions on minimum water level ensure that sufficient water depth is available to: remove 99.5% of the assumed 16% 1-131 and 10% other halogens gap activity

,released from the rupture of an irradiated fuel assembly. The minimum water depth is consistent with the assumptions of the accident analysis.

• is important to RHR SUMMER - UNIT 1 B 3/4 9-2 Amendment No. 40 BRN-1 1-001

IINSERT 4 RESIDUlAL HEAT REMOVAL AND COOLANT CIRCULATION (Continued)

RI{A 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 loops and may also prevent water hammer, pump cavitation, and pumping of non-condensible gas into the reactor vessel.

Selection of RHR System locations susceptible to gas accumulation is based on a review of system design information; including piping and instrument drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walkdowns 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 standby versus operating conditions.

• The RHR System is OPERABLE when it is sufficiently filledwith 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 thae 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 detenmined by subsequent. evaluation that the RHR~ 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.

RHRl~ 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 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, 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 31 day frequency for ensuring locations are sufficiently filled with water takes into consideraition the gradual nature of gas accumulation in the RHR System piping and the procedural controls governing system operation.

Document Control Desk LAR/CR-08-001 62 RC-15-01 13 Attachment V Page 1 of 10 VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) Unit 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 Attachment V TS Bases (Clean)

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-Insert Pages TS Bases Page 3/4-4-1

"*TS Bases Page 3/4-4-1 TS Bases Page 3/4-4-1 a TS Bases Page 3/4-5-1 TS Bases Page 3/4-5-1

-. TS Bases Page 3/4-5-2 TS Bases Page 3/4-5-2

-- *TS Bases Page 3/4-5 -2 a TS Bases Page 3/4-6-3 TS Bases Page 3/4-6-3 TS Bases Page 3/4-6-3a TS Bases Page 3/4-9-2 TS Bases Page 3/4-9-2 TS Bases Page 3/4-9-3 TS Bases Page 3/4-9-3

3.4.4 REACTOR COOLANT SYSTEM BASES 3/4.4.1 REACTOR COOLANT LOOPS AND COOLANT CIRCULATION The plant is designed to operate with all reactor coolant loops in operation, and maintain DNBR in the core at or above the design limit during all normal operations and anticipated transients. In MODES 1 and 2 with one reactor coolant loop not in operation this specification requires that the plant be in at least HOT STANDBY within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />.

In MODE 3, a single reactor coolant loop provides sufficient heat removal capability for removing decay heat; however, single failure considerations require that two loops be OPERABLE.

In MODE 4, and in MODE 5 with reactor coolant loops filled, a single reactor coolant loop or RHR loop provides sufficient heat removal capability for removing decay heat; but single failure considerations require that at least two loops (either RHR or RCS) be OPERABLE. Management of gas voids is important to RHR System OPERABILITY.

In MODE 5 with reactor coolant loops not filled, a single RHR loop provides sufficient heat removal capability for removing decay heat; but single failure

• considerations, and the unavailability of the steam generators as a heat removing component, require that at least two RHR loops be OPERABLE. Management of gas voids is important to RHR System OPERABILITY.

The operation of one Reactor Coolant Pump or one RHR pump provides adequate flow to ensure mixing, prevent stratification and produce gradual reactivity changes during boron concentration reductions in the Reactor Coolant System. The reactivity change rate associated with boron reduction will, therefore, be within the capability of operator recognition and control.

The restrictions on starting a Reactor Coolant Pump with one or more RCS cold legs less than or equal to 300°F are provided to prevent RCS pressure transients, caused by energy additions from the secondary system, which could exceed the limits of Appendix G to 10 CFR Part 50. The RCS will be protected against overpressure transients and will not exceed the limits of Appendix G by either (1) restricting the water volume in the pressurizer and thereby providing a volume for the primary coolant to expand into, or (2) by restricting starting of the RCPs to when the secondary water temperature of each steam generator is less than 50°F above each of the RCS cold leg temperatures.

SUMMER-UNIT 1 B 3/4 4-1 SUMMR

- NIT B 344-1Amendment No.

REACTOR COOLANT SYSTEM BASES REACTOR COOLANT LOOPS AND COOLANT CIRCULATION (Continued)

RHR 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 loops and may also prevent water hammer, pump cavitation, and pumping of non-condensable gas into the reactor vessel.

Selection of RHR System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrument drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walkdowns 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 standby versus operating conditions.

The RHR 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 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 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 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, 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.

Surveillance Requirement 4.4.1.3.4 is modified by a Note that states the Surveillance Requirement is not required to be performed until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after entering MODE 4. In a rapid shutdown, there may be insufficient time to verify all susceptible locations prior to entering MODE 4.

The 31 day frequency for ensuring locations are sufficiently filled with water takes into consideration the gradual nature of gas accumulation in the RHR System piping and the procedural controls governing system operation.

SUMMER - UNIT 1 B344l mnmn o

B 3/4 4-1a Amendment No.

3/4.5 EMERGENCY CORE COOLING SYSTEMS BASES 3/4.5.1 ACCUMULATORS The OPERABILITY of each Reactor Coolant System (RCS) accumulator ensures that a sufficient volume of borated water will be immediately forced into the reactor core through each of the cold legs in the event the RCS pressure falls below the pressure of the accumulators. This initial surge of water into the core provides the initial cooling mechanism during large RCS pipe ruptures. In addition, the borated water serves to limit the maximum power which may be reached during large secondary pipe ruptures.

The limits on accumulator volume, boron concentration and pressure ensure that the assumptions used for accumulator injection in the safety analysis are met.

The accumulator power operated isolation valves were originally considered to be "operating bypasses". in the context of IEEE Std. 279-1971, which requires that bypasses of a protective function be removed automatically whenever permissive conditions are not met.

In addition, as these accumulator isolation valves fail to meet single failure criteria, removal of power to the valves is required.

The limits for operation with an accumulator inoperable for any reason except an isolation valve closed minimizes the time exposure of the plant to a LOCA event occurring concurrent with failure of an additional accumulator which may result in unacceptable peak cladding temperatures. If a closed isolation valve cannot be immediately opened, the full capability of one accumulator is not available and prompt action is required to place the reactor in a mode where this capability is not required.

3/4.5.2 and 3/4.5.3 EMERGENCY CORE COOLING SYSTEM (ECCS) SUBSYSTEMS The OPERABILITY of two independent ECCS subsystems ensures that sufficient.

emergency core cooling capability will be available in the event of a LOCA assuming the loss of one subsystem through any single failure consideration. Either subsystem operating in conjunction with the accumulators is capable of supplying sufficient core cooling to limit the peak cladding temperatures within acceptable limits for all postulated break sizes ranging from the double ended break of the largest RCS cold leg pipe downward. In addition, each ECCS subsystem provides long term core cooling capability in the recirculation mode during the accident recovery period. Management of gas voids is important to ECCS OPERABILITY.

With the RCS temperature below 350°F, one OPERABLE ECCS subsystem is acceptable without single failure consideration on the basis of the stable reactivity condition of the reactor and the limited core cooling requirements.

SUMMER-UNIT 1 B 3/4 5-1 SUMME

- UIT 1B 3/ 5-1Amendment No. 7-5,

4 m

EMERGENCY CORE COOLING SYSTEMS BASES ECCS SUBSYSTEMS (Continued)

The limitation for a maximum of one centrifugal charging pump to be OPERABLE and the Surveillance Requirement to verify all charging pumps except the. required OPERABLE

• charging pump to be inoperable below 300°F provides assurance that a mass addition pressure transient can be relieved by the operation of a single RHR suction relief valve.

The Surveillance Requirements provided to ensure OPERABILITY of each component ensures that at a minimum, the assumptions used in the safety analyses are met and that subsystem OPERABILITY is maintained. Surveillance requirements for throttle valve position stops and flow balance testing provide assurance that proper ECCS flowswill be maintained in the event of a LOCA. Maintenance of proper flow resistance and pressure drop in the piping system to each injection point is necessary to: (1) prevent total pump flow from exceeding runout conditions when the system is in its minimum resistance configuratiOn, (2) provide the proper flow split between injection points in accordance with the assumptions used in the ECCS-LOCA analyses, and (3) provide an acceptable level of total ECCS flow to all injection points equal to or above that assumed in the ECCS-LOCA analyses.

ECCS 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 ECCS and may also prevent water hammer, pump cavitation, and pumping of non-condensable gas into the reactor vessel.

Selection of ECCS locations susceptible to gas accumulation is based on a review of system design information, including piping and instrument drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walkdowns 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 standby versus operating conditions.

The ECCS is.OPERABLE when it is sufficiently filled with water. *Acceptance criteria are established for the volume of accumulated gas at susceptible locationis. 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 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.

ECCS 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 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, plant configuration, or personnel safety. For these locations, alternative methods SUMMER-UNIT 1 B 3/4 5-2 SUMMR

-UNI I B3/45-2Amendment No.4A4-2.

EMERGENCY CORE COOLING SYSTEMS BASES ECCS SUBSYSTEMS (Continued)

(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.

Surveillance Requirement 4.5.2.b.1) 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 at the system vent path who is in continuous communication with the operators in the control room. The individual will have a method to rapidly close the system vent flow path if directed.

The 31 day frequency for Surveillance Requirement 4.5.2.b.2) taken into consideration the gradual nature of gas accumulation in the ECCS piping and the procedural controls governing system operation.

3/4.5.4 REFUELING WATER STORAGE TANK The OPERABILITY of the Refueling Water Storage Tank (RWST) as part of the ECCS ensures that a sufficient supply of borated water is available for injection by the ECCS in the event of either a LOCA, a steamline break or inadvertent RCS depressurization. The limits of RWST minimum volume and boron concentration ensure 1) that sufficient water is available within containment to permit recirculation cooling flow to the core, 2) that the reactor will remain subcritical in the cold condition (68 to 212 degrees-F) following a small break LOCA assuming complete mixing of the RWST, RCS, Spray Additive Tank (SAT), containment spray system piping and ECCS water volumes with all control rods inserted except the most reactive control rod assembly (ARI-1), 3) that the reactor will remain subcritical in the cold condition following a large break LOCA (break flow area > 3.0 sq. ft.) assuming complete mixing of the RWST, RCS, ECCS water and other sources of water that may eventually reside in the sump post-LOCA with all control rods assumed to be out (ARO), 4) long term subcriticality following a steamline break assuming ARI-1 and preclude fuel failure.

The maximum allowable value for the RWST boron concentration forms the basis for determining the time (Post-LOCA) at which operator action is required to switch over the ECCS to hot leg recirculation in order to avoid precipitation of the soluble boron.

The contained water volume limit includes an allowance for water not usable because of tank discharge line location or other physical characteristics.

SUMMER - UNIT 1

/ -aAmnmn o

B 3/4 5-2a Amendment No.

CONTAINMENT SYSTEMS BASES 3/4.6.1.7 REACTOR BUILDING VENTILATION SYSTEM The 36-inch containment purge supply and exhaust isolation valves are required to be closed during plant operation since these valves have not been demonstrated capable of closing during a LOCA or steam line break accident. Maintaining these valves closed during plant operations ensures that excessive quantities of radioactive materials will not be released via the containment purge system. To provide assurance that the 36-inch valves cannot be inadvertently opened, they are sealed closed in accordance with Standard Review Plan 6.2.4 which includes mechanical devices to seal or lock the valve closed, or prevent power from being supplied to the valve operator.

The use of the containment purge lines is restricted to the 6 inch purge supply and exhaust isolation valves since unlike the 36 inch valves the 6 inch valves will close during a LOCA or steam line break accident and therefore the site boundary dose guidelines of 10 CFR 100 would not be exceeded in the event of an accident during purging operations.

Periodic leakage integrity tests for purge supply and exhaust isolation valves with resilient material seals will be performed in accordance with the Containment Leakage Rate Testing Program.

3/4.6.2 DEPRESSURIZATION AND COOLING SYSTEMS 3/4.6.1.1 REACTOR BUILDING SPRAY SYSTEM The OPERABILITY of the reactor building spray system ensures that reactor building depressurization and cooling capability will be available in the event of a steam line break. The pressure reduction and resultant lower containment leakage rate are consistent with the assumptions used in the accident analyses.

The reactor building spray system and the reactor building cooling system are redundant to each other in providing post accident cooling of the reactor building atmosphere. However, the reactor building spray system also provides a mechanism for removing iodine from the reactor building atmosphere and therefore the time requirements for restoring an inoperable spray system to OPERABLE status have been maintained consistent with that assigned other inoperable ESF equipment.

Management of gas voids is important to Containment Spray System OPERABILITY.

SUMMER-UNIT 1 B 3/4 6-3 SUMME

- UIT 1B 3/

6-3 Amendment No. 45

.1r i,*,

CONTAI NMENT SYSTEMS BASES REACTOR BUILDING SPRAY SYSTEM (Continued)

S Containment Spray System flow path 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 containment spray

..,trains and may also prevent a water hammer and pump cavitation.

Selection of Containment Spray System locations susceptible to gas "accumulation is based on a review of system design information, including piping and instrument drawings, isometric drawings, plan and elevation drawings, and calculations.

The design review is supplemented by system walkdowns 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 standby versus operating conditions.

The Containment 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 S: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 Containment 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.

Containment 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 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, plant configuration, or

• personnel safety. For these locations, alternative methods (e.g., operating parameters, Sremote.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 31 day frequency for Surveillance Requirement 4.6.2.1.a.1) takes into

• consideration the gradual nature of gas accumulation in the Containment Spray System piping and the procedural controls governing system operation.

Surveillance Requirement 4.6.2.1.a.1) 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 at the system vent path who is in continuous communication with the operators in the control room.

The individual will have a method to rapidly close the system vent flow path if directed.

SUMMER-UNIT 1 B 3/4 6-3a Amendment No.

REFUELING OPERATIONS BASES 3/4.9.6 MANIPULATOR CRANE The OPERABILITY requirements for the manipulator cranes ensure that:

1) manipulator cranes will be used for movement of control rods and fuel assemblies,

2) each crane has sufficient load capacity to lift a control rod and fuel assembly, and

3) the core internals and pressure vessel are protected from excessive lifting force in the event they are inadvertently engaged during lifting operations.

3/4.9.7 RESIDUAL HEAT REMOVAL AND COOLANT CIRCULATION The requirement that at least one residual heat removal loop be in operation ensures that 1) sufficient cooling capacity is available to remove decay heat and maintain the water in the reactor pressure vessel below 1400°F as required during the REFUELING MODE, and

2) sufficient coolant circulation is maintained through the reactor core to minimize the effects of a boron dilution incident and prevent boron stratification. Management of gas voids is important to RHR System OPERABILITY.

The requirement to have two RHR loops OPERABLE when there is less than 23 feet of water above the reactor pressure vessel flange ensures that a single failure of the operating RHR loop will not result in a complete loss of residual heat removal capability.

With the reactor vessel head removed and at least 23 feet of water above the reactor pressure vessel flange, a large heat sink is available for core cooling. Thus, in the event of a failure of the operating RHR loop, adequate time is provided to initiate emergency procedures to cool the core.

RHR System flow path 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 containment spray trains and may also prevent a water hammer and pump cavitation.

Selection of RHR System locations susceptible to gas accumulation is based on a review of system design information, including piping and instrument drawings, isometric drawings, plan and elevation drawings, and calculations. The design review is supplemented by system walkdowns 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 standby versus operating conditions.

SUMMER-UNIT 1 B 3/4 9-2 SUMMER-UNI I B 34 9-2Amendment No.

60

REFUELING OPERATIONS BASES RESIDUAL HEAT REMOVAL AND COOLANT CIRCULATION (Continued)

The RHR 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 Containment 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 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 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, 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 31 day frequency for ensuring locations are sufficiently filled with water takes into consideration the gradual nature of gas accumulation in the RHR System piping and the procedural controls governing system operation.

3/4.9.8 DELETED BY AMENDMENT 183 3/4.9.9 WATER LEVEL - REACTOR VESSEL The restrictions on minimum water level ensure that sufficient water depth is available to remove 99.5% of the assumed 16% 1-131 and 10% other halogens gap activity released from the rupture of an irradiated fuel assembly. The minimum water depth is consistent with the assumptions of the accident analysis.

SUMMER - UNIT 1 B 3/4 9-3 Amendment No. 4 3

8RN ! 09!,

~1

-g Document Control Desk LAR/CR-08-001 62 RC-15-01 13 Attachment VI Page 1 of I VIRGIL C. SUMMER NUCLEAR STATION (VCSNS) Unit 1 DOCKET NO. 50-395 OPERATING LICENSE NO. NPF-12 Attachment V LIST OF REGULATORY COMMITMENTS This document contains no new commitments.