ML20211F131

Forwards Rev 1 to Calculation Nedc 97-044, NPSH Margins for RHR & CS Pumps, in Support of 990615 Proposed Amend to DPR-46 Re Containment Overpressure Contribution to ECCS Pumps NPSH Requirements

ML20211F131
Person / Time
Site:	Cooper
Issue date:	08/24/1999
From:	Newman L NEBRASKA PUBLIC POWER DISTRICT
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20211F135	List: ML20211F131 ML20211F136
References
NLS990080, NUDOCS 9908300248
Download: ML20211F131 (5)

Text

N Nebraska Public Power District Nebraska's Energy Leader i

NLS990080 August 24,1999 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001 Gentlemen:

Subject:

Proposed License Amendment Containment Overpressure Contribution to ECCS Pump I

NPSH Requirement Post LOCA Response to Request for Supporting Documentatin Cooper Nuclear Station, NRC Docket 50-298, DPR-46

Reference:

Letter NLS990052 to USNRC from J. H. Swailes (NPPD) dated June 15,1999,

" Proposed License Amendment, Containment Overpressure Contribution to ECCS Pump NPSH Requirement Post LOCA, Cooper Nuclear Station, NRC Docket 50-298, DPR-46."

In the above reference, the Nebraska Public Power District (District) submitted to the Nuclear Regulatory Commission (NRC) a proposed change to the Cooper Nuclear Station (CNS)

Operating License concerning the Contaimnent Overpressure Contribution to Emergency Core Cooling System (ECCS) Pumps Net Positive Suction Head (NPSH) Requirements. In a telephone communication between the NRC Nuclear Reactor Regulation (NRR) Project Manager for CNS and the CNS Nuclear Licensing & Safety (NL&S) Manager on July 21,1999, the NRC NRR Project Manager requested that the NPSH and ECCS Pump suction strainer hydraulic sizing calculations be submitted to support review of this proposed Licensing Amendment. In accordance with this request, please find enclosed a copy of NEDC 97-044 which is the calculation of record for both of these issues.

Cooper Nuclear Station calculation NEDC 97-044 determines the NPSH margins and containment over pressure requirements for the Residual Heat Removal (RHR) and Core Spray pumps under a Design Basis Accident (DBA) Loss of Coolant Accident (LOCA). It also contains historical information as well as sensitivity cases for "Non - DBA" scenarios.

4 The information previously submitted to the NRC, per NLS990052, is based on the DBA LOCA scenario. Therefore, there is information in this calculation that does not pertain directly to the submittat The following information will help guide the NRC reviewers to the applicable sections ofNEDC 97-044:

8 g 001, t)P/(gOQ%

Cooper Nudear Station 999g g gg 99 g 4 u 98/ Brownville. NE 68321-0098 PDR ADOCK 05000398

'H"Q2)825'8"/f**H'02)825^52" P

PDR httpf/www.nppd (om iL

NLS990080 August 24,1999 Page 2 of 3 Main Body of Calculation (cover page thru page 11 of 11) - This lists the Purpose, Assumptions, References, Methodology, and Conclusions. The design basis assumptions, as well as assumptions for sensitivity cases are included here.

l Attachment B - This shows the " margins" between available containment over pressure and required containment over pressure for the design basis scenario. Absolute values of pressure are not shown. The curves and tables are provided for the two divisions (i.e., RHR and Core Spray Loop Division I, and then Division II). Tabular data is also provided.

Attachment E - The curves on page 1 of 12 and 2 of 12 are the design basis scenario and are based on the same data as presented in the License Amendment. Only the " worst case" division is shown. The curve is split into a short term curve ( 0 to 1,000 seconds) on a linear scale and long term curve (1,000 to 100,000 seconds) on a log scale. The License Amendment included 500 to 100,000 seconds, all on a single curve, log scale. Five hundred seconds was chosen for the submittal since the lowest " margin" occurs after 500 seconds.

Attachments II and I show the macro and cell equations, respectively, used in the Excel spreadsheet for calculating NPSH margins and pressure requirements. Attachment I also contains the tr.bular data for suppression pool temperature and wetwell pressure taken from the CNS containment analysis, GE report GENE-637-045-1293 (Note: this GE repon is contained in Cooper Nuclear Station calculation NEDC 94-034).

Attachment M - Tabular data for the design basis scenario. This was used to generate the curve in the License Amendment (NLS990052) and the curves on sheets 1 and 2 of Attachment E to this calculation.

Should you have any questions regarding this matter, please contact me.

Sincerely, b

Larry an NL&S Manager

/rar Enclosure cc: Regional Administrator w/ enclosure USNRC - Region IV I

Senior Project Manager w/ enclosure USNRC - NRR Project Directorate IV-1 r

e

7.

i NLS990080 August 24,1999 Page 3 of 3 Senior Resident Inspector w/ enclosure USNRC Environmental Health Division - Program Manager w/ enclosure Nebraska Department of Health NPG Distribution w/o enclosure l

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l ATTACHMEET 3 LIST OF NRC COMMITMEMTS l

Correspondence No: NLS990090 i

The following table identifies those actions committed to by the District in this document. Any other actions discussed in the submittal represent intended or l

planned actions by the District.

They are described to the NRC for the NRC's information and are not regulatory commitments.

Please notify the NL&S Manager at Cooper Nuclear Station of any questions regarding this document or any associated regulatory commitments.

COMMITTED DATE COMMITMENT OR OUTAGE l

None N/A l

PROCEDURE NUMBER 0.42 l

REVISION NUMBER 6 l

PAGE 9 OF 13 l

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