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Vinoisir Ei. ice aiC AND Powr.n Cous ANY| RICIINIOND, YIRGINI A 232(il1

' ' July 28, 1998

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U.S. Nuclear Regulatory Commission Serial No. 98-434Attention: Document Control Desk NL&OS/GSS/ETS R05Nashington, D.C. 20555 Docket Nos. 50-338

50-339License Nos. NPF-4

NPF-7Gentlemen:

VIRGINIA ELECTRIC AND POWER COMPANYNORTH ANNA POWER STATION UNITS 1 AND 2PROPOSED TECHNICAL SPECIFICATION CHANGECASING COOLING AND OUTSIDE RECIRCULATION SPRAY PUMPSREVISED SURVEILLANCE TESTING CRITERIA

Pursuant to 10 CFR 50.90, Virginia Electric and Power Company requestsamendments, in the form of changes to the Technical Specifications and to FacilityOperating License Numbers NPF-4 and NPF-7 for North Anna Power Station Units 1,

[gand 2, respectively. The proposed changes will revise the testing acceptance criteria todemonstrate operability of the casing cooling and outside recirculation spray pumps. Adiscussion of the proposed Technical Specifications changes is provided in Attachment

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The proposed Technical Specifications changes have been reviewed and approved bythe Station Nuclear Safety and Operating Committee and the Management SafetyReview Committee. It has been determined that the proposed Technical Specificationschanges do not involve an unreviewed safety question as defined in 10 CFR 50.59 or asignificant hazards consideration as defined in 10 CFR 50.92. The proposed TechnicalSpecifications changes are provided as a mark-up in Attachment 2 and as a typedversion in Attachment 3. The basis for our determination that the changes do notinvolve a significant hazards consideration is provided in Attachment 4.

If you have any further questions, please contact us.

Very truly yours,

,

James P. O'HanlonSenior Vice President - Nuclear

9807310101 900728PDR ADOCK 0500o338p PDR

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Attachments

1. Discussion of Changes2. Mark-up of Technical Specifications Changes3. Proposed Technical Specifications Changes4. Significant Hazards Consideration Determination

Commitments made in this letter:

1. There are no commitments in this letter

cc: U.S. Nuclear Regulatory CommissionRegion !!Atlanta Federal Center !

61 Forsyth Street, SWSuite 23T85Atlanta, Georgia 30303

Mr. M. J. MorganNRC Senior Resident inspectorNorth Anna Power Station

Commissioner i

Department of Radiological Health )'

Room 104A |

1500 East Main StreetRichmond,VA 23219

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COMMONWEALTH OF VIRGINIA )! )

COUNTY OF HENRICO )

The foregoing document was acknowledged before me, in and for the Countyand Commonwealth aforesaid, today by J. P. O'Hanlon, who is Senior VicePresident - Nuclear, of Virginia Electric and Power Company. He has affirmedbefore me that he is duly authorized to execute and file the foregoing documentin behalf of that Company, and that the statements in the document are true tothe best of his knowledge and belief.

Acknowledged before me thisOO day of LV ,19 .

My Commission Expires: March 31,2000.

-rwrit EmD/ Notary Public

(SEAL)

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Attachment 1

Discussion of Change

North Anna Power StationUnits 1 and 2

Virginia Electric and Power Company

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DISCUSSION OF CHANGE--

Introduction

Pursuant to 10 CFR 50.90, Virginia Electric and Power Company requests changes toTechnical Specifications Surveillance Requirements (SR) 4.6.2.2.1.b whichdemonstrate operability of each containment recirculation spray and casing coolingsubsystem for North Anna Power Station Units 1 and 2. SR 4.6.2.2.1.b requiresverification, during recirculation flow, that each outside recirculation spray pumpdevelops a discharge pressure of greater than or equal to 115 psig and that eachCasing C oling pump develops a discharge pressure of greater the i or equal to 58 psigfor Unit 1 and 46 psig for Unit 2 when tested. The proposed changes will revise thetesting acceptance criteria being verified from discharge pressure :o the requireddeveloped head. The frequency of testing shall be in accordance with the InserviceTesting Program. These changes are consistent with the testing acceptance criteriaspecified in NUREG 1431, " Standard Technical Specifications, Westinghouse Plants."

The proposed changes will not affect the capability of the containment RS system toperform its intanded design functions. The sysicm performance will remain bounded bythe existing accident analysis basis. Therefore, the proposed changes to the testintfacceptance criteria for the Casing Cooling and outside recirculation pumps do notcreate an unreviewed safety question.

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Background i

Current Licensing Basis '

General Design Criteria 38, " Containment Heat Removal," 39, " Inspection ofContainment Heat Removal Systems," and 40, " Testing of Containment Heat Removal l

Systems" provide the system design, testing and inspection requirements to removeheat from the reactor containment. The safety function is to reduce rapidly, consistentwith the functioning of other associated systems, the containment pressure and '

temperature following any loss-of-coolant accident and maintain them at an acceptablelevel.

Based upon the results of the NRC's initial review and Safety Evaluation Report, it was Jconcluded that the design of the containment heat removal systems and the NAPSTechnical Specifications provide the necessaiy surveillance requirements, testingfrequencies, and desig;i basis to satisfy the General Design Criteria of 10,CFR50Appendix A.

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. Design Basis.

The containment Recirculation Spray (RS) System, in conjunction with the Containment |Quench Spray System, is designed to limit post-accident pressure and temperature i:the containment to less than the design values and to depressurize the containment to |

subatmospheric pressure in less than 60 minutes. The RS System consists of fourseparate but parallel RS subsystems. Two RS pumps and moters are located insidethe containment structure and two are located outside the containment. Following a ,

LOCA, water accumulates in the containment sump which provides a suction for the )four RS pumps. The water is continuously recirculated through the containment to,

remove heat from the reactor core and containment atmosphere sud to remove !radioiodine from the containment atmosphere, l

The Casing Cooling subsystem which is considered part of the outside RS subsystem i

consists of a casing cooling tank, two casing cooling recirculation pumps, two. refrigeration units, and two casing cooling pumps. This subsystem provides cool waterto the outside RS pumps to increase their net positive suction head.

Discussioni

The current Technical Specification Surveillance Requirements require the CasingCooling and ORS pumps to develop a discharge pressure to demonstrate operability.This is accomplished by verifying that on recirculation flow, each outside recirculationspray (ORS) pump develops a discharge pressure of greater than or equal to 115 psig,and that each casing cooling pump develops a discharge pressure of greater than orequal to 58 psig for Unit 1 and 46 psig for Unit 2.

In response to the recommended corrective actions to wation Deviation Reports andPotential Problem Reports which have shown that these discharge pressures wereincorrect, the proposed changes will provide new acceptance criteria based upon thecurrent plant conditions. Changes will verify operability that each RS and CasingCooling pump's developed head at the flow test point is greater or equal to the requireddeveloped head. This is consistent with the acceptance criteria specified in NUREG-1431, " Standard Technical Specifications. Westinghouse Plants" and provides a moreaccurate assessment of pump performance.

Standard Technical Specifications Surveillance Requirement (NUREG-1431) for theRecirculation Spray System requires the verification of each RS and Casing Coolingpump's developed head at the flow test point to be greater than or equal to the requireddeveloped head. The proposed changes will revise the current verificationrequirements for the ORS and the Casing Cooling pumps to be consistent with the

! Standard Technical Specifications.

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Casing Cooling and ORS pumps which meet the proposed acceptance criteria duringperiodics testing will be capable of supplying the required design basis flow tocontainment during a Loss of Coolant Accident (LOCA) or a Main Steam Line Break(MSLB). The proposed changes to the Technical Specifications will ensure that theCasing Cooling and ORS pumps will supply the minimum or greater design basis fhwsto containment during a LOCA or MSLB and refer to the Inservice Testing Program fortesting frequency. There is no safety significance since the pump performance dataobtained with the periodic test procedures are in agreement with the vendor's pumpcurves used in the system calculation. The data shows no trends for any pumpdegradation.

Specific Changes

Proposed changes will delete the current Su veillance Requirement 4.6.2.2.1.b for Units1 and 2 and replace it with the following:

" Verify each RS and Casing Cooling pump's developed head at the flow test pointis greater than or equal to the required developed head. The frequency shall bein accordance with the Inservice Testing Program."

Safety Significance !

Incorporating the required developed head and the Inservice Testing Program testfrequency into the Technical Specific itions does not affect plant operation ordesign. The use of this Casing Cooling and ORS test criteria will confirm that the

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Casing Coonng and ORS pumps are operating at or above pump dergn TDH'

curves and will ensure that the pumps deliver their design basis tiows during aDBA. I

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a) Operation under the proposed Technical Specification changes does notincrease the probability of occurrence or the consequences of an accident or jmalbnctica of equipment important to safety previously evaluated in the {safety analysis report. {

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The proposed changes will ensure that the Casing Cooling and ORS pumpswill perform properly with no unacceptable degradation by using the correctpump test acceptance criteria and refer to the Inservice Testing Program fortesting frequency. This does not increase the probability of a LOCA/MSLB >

accident.

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Therefore, the proposed test sequence does not increase the probability of j

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b) The proposed Technical Specifications do not create the possibility of an.

accident or malfunction of a different type than any evaluated previous!y in.

the safety analysis report.

The propsed changes will ensure that the Casing Cooling and ORS pumpsare properly tested at the frequency required by inservice Testing Programto confirm their ability to provide design basis flow during a LOCA/MSLB.This will not result in any physical alteration to any plant system, nor wouldthere be a change in the method by which any safety related systemperforms its function. The design and operation of the Casing Cooling andORS systems are not being changed. Also, the proposed changes do nctaffect the design, operation or failure modes of the Casing Cooling and ORSpumps and other components within the Casing Cooling and ORS systems.

Therefore, the proposed changes do not create the possibility of a new ordifferent kind of accident or malfunction previously evaluated.

c) The proposed Technical Spec:fications change does not result in a reductionin margin of safety as defined in the basis for any Technical Specifications.

Implementation of the proposed changes ensures that the Casing Cooling andORS pumps do not operate with unacceptable degraded f!ows during aLOCA/MSLB that are less than their conta:nment analysis design basis flow.

Therefore, the proposed changes would not reduce the margin of safety asdefined in the basis for any Technical Specification.

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Attachment 2

!Mark-up of Technical Specifications Changes

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North Anna .Nower StationUnits 1 and 2

Virginia Electric and Power Company|

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Unit 1

Mark-up of Technical Specifications Changes

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