ML20236U826

Application for Amends to Licenses NPF-4 & NPF-7,revising Testing Acceptance Criteria to Demonstrate Operability of Casing Cooling & Outside Recirculation Spray Pumps

ML20236U826
Person / Time
Site:	North Anna
Issue date:	07/28/1998
From:	Ohanlon J VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20236U827	List: ML20236U826 ML20236U841
References
98-434, NUDOCS 9807310101
Download: ML20236U826 (10)

Text

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Vinoisir Ei. ice aiC AND Powr.n Cous ANY l RICIINIOND, YIRGINI A 232(il 1

July 28, 1998 l

l U.S. Nuclear Regulatory Commission Serial No.98-434 Attention: Document Control Desk NL&OS/GSS/ETS R0 5Nashington, D.C. 20555 Docket Nos. 50-338 50-339 License Nos. NPF-4 NPF-7 Gentlemen:

VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNITS 1 AND 2 PROPOSED TECHNICAL SPECIFICATION CHANGE CASING COOLING AND OUTSIDE RECIRCULATION SPRAY PUMPS REVISED SURVEILLANCE TESTING CRITERIA Pursuant to 10 CFR 50.90, Virginia Electric and Power Company requests amendments, in the form of changes to the Technical Specifications and to Facility

, Operating License Numbers NPF-4 and NPF-7 for North Anna Power Station Units 1 and 2, respectively. The proposed changes will revise the testing acceptance criteria to [g demonstrate operability of the casing cooling and outside recirculation spray pumps. A discussion of the proposed Technical Specifications changes is provided in Attachment 1 1-rf)OJ The proposed Technical Specifications changes have been reviewed and approved by the Station Nuclear Safety and Operating Committee and the Management Safety Review Committee. It has been determined that the proposed Technical Specifications changes do not involve an unreviewed safety question as defined in 10 CFR 50.59 or a significant hazards consideration as defined in 10 CFR 50.92. The proposed Technical Specifications changes are provided as a mark-up in Attachment 2 and as a typed version in Attachment 3. The basis for our determination that the changes do not involve a significant hazards consideration is provided in Attachment 4.

If you have any further questions, please contact us.

Very truly yours, James P. O'Hanlon Senior Vice President - Nuclear 9807310101 900728 PDR ADOCK 0500o338 p PDR l

. u Attachments

1. Discussion of Changes

2. Mark-up of Technical Specifications Changes

3. Proposed Technical Specifications Changes

4. Significant Hazards Consideration Determination Commitments made in this letter:

1. There are no commitments in this letter cc: U.S. Nuclear Regulatory Commission Region !!

Atlanta Federal Center  !

61 Forsyth Street, SW Suite 23T85 Atlanta, Georgia 30303 Mr. M. J. Morgan NRC Senior Resident inspector North Anna Power Station Commissioner i Department of Radiological Health )

Room 104A l 1500 East Main Street Richmond,VA 23219 I

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COMMONWEALTH OF VIRGINIA )

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COUNTY OF HENRICO )

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

Acknowledged before me thisOO day of LV ,19 .

My Commission Expires: March 31,2000.

-rwrit EmD

/ Notary Public (SEAL)

l Attachment 1 Discussion of Change North Anna Power Station Units 1 and 2 Virginia Electric and Power Company

DISCUSSION OF CHANGE Introduction Pursuant to 10 CFR 50.90, Virginia Electric and Power Company requests changes to Technical Specifications Surveillance Requirements (SR) 4.6.2.2.1.b which demonstrate operability of each containment recirculation spray and casing cooling subsystem for North Anna Power Station Units 1 and 2. SR 4.6.2.2.1.b requires verification, during recirculation flow, that each outside recirculation spray pump develops a discharge pressure of greater than or equal to 115 psig and that each Casing C oling pump develops a discharge pressure of greater the i or equal to 58 psig for Unit 1 and 46 psig for Unit 2 when tested. The proposed changes will revise the testing acceptance criteria being verified from discharge pressure :o the required developed head. The frequency of testing shall be in accordance with the Inservice Testing Program. These changes are consistent with the testing acceptance criteria specified in NUREG 1431, " Standard Technical Specifications, Westinghouse Plants."

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

J Background i Current Licensing Basis General Design Criteria 38, " Containment Heat Removal," 39, " Inspection of Containment Heat Removal Systems," and 40, " Testing of Containment Heat Removal l Systems" provide the system design, testing and inspection requirements to remove heat from the reactor containment. The safety function is to reduce rapidly, consistent with the functioning of other associated systems, the containment pressure and '

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

Based upon the results of the NRC's initial review and Safety Evaluation Report, it was J concluded that the design of the containment heat removal systems and the NAPS Technical Specifications provide the necessaiy surveillance requirements, testing frequencies, and desig;i basis to satisfy the General Design Criteria of 10,CFR50 Appendix A.

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. Design Basis The containment Recirculation Spray (RS) System, in conjunction with the Containment l 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 l subatmospheric pressure in less than 60 minutes. The RS System consists of four separate but parallel RS subsystems. Two RS pumps and moters are located inside the 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 water to the outside RS pumps to increase their net positive suction head.

Discussion i

The current Technical Specification Surveillance Requirements require the Casing Cooling and ORS pumps to develop a discharge pressure to demonstrate operability.

This is accomplished by verifying that on recirculation flow, each outside recirculation spray (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 or equal to 58 psig for Unit 1 and 46 psig for Unit 2.

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

Standard Technical Specifications Surveillance Requirement (NUREG-1431) for the Recirculation Spray System requires the verification of each RS and Casing Cooling pump's developed head at the flow test point to be greater than or equal to the required developed head. The proposed changes will revise the current verification requirements 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 during periodics testing will be capable of supplying the required design basis flow to containment during a Loss of Coolant Accident (LOCA) or a Main Steam Line Break (MSLB). The proposed changes to the Technical Specifications will ensure that the Casing Cooling and ORS pumps will supply the minimum or greater design basis fhws to containment during a LOCA or MSLB and refer to the Inservice Testing Program for testing frequency. There is no safety significance since the pump performance data obtained with the periodic test procedures are in agreement with the vendor's pump curves used in the system calculation. The data shows no trends for any pump degradation.

Specific Changes Proposed changes will delete the current Su veillance Requirement 4.6.2.2.1.b for Units 1 and 2 and replace it with the following:

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

Safety Significance  !

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

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 a DBA. I l

a) Operation under the proposed Technical Specification changes does not increase the probability of occurrence or the consequences of an accident or j malbnctica of equipment important to safety previously evaluated in the {

safety analysis report. {

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

accident.

Therefore, the proposed test sequence does not increase the probability of j l occurrence or the consequences of any previously ar:alyzed accident. J l

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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 pumps are properly tested at the frequency required by inservice Testing Program to 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 would there be a change in the method by which any safety related system performs its function. The design and operation of the Casing Cooling and ORS systems are not being changed. Also, the proposed changes do nct affect the design, operation or failure modes of the Casing Cooling and ORS pumps and other components within the Casing Cooling and ORS systems.

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

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

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

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

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l Attachment 2 Mark-up of Technical Specifications Changes i

North Anna .Nower Station Units 1 and 2 Virginia Electric and Power Company l

Unit 1 Mark-up of Technical Specifications Changes l  !

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