ML20141F426

Responds to Request Re Credit Containment Overpressure to Satisfy Net Positive Suction Head Requirements & Subsequent Deferral of Review Request Based on 10CFR50.59 Evaluation

ML20141F426
Person / Time
Site:	Pilgrim
Issue date:	06/30/1997
From:	Milano P NRC (Affiliation Not Assigned)
To:	Boulette E BOSTON EDISON CO.
References
TAC-M97789, NUDOCS 9707020360
Download: ML20141F426 (4)

Text

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j .p* \ UNITED STATES l , g j NUCLEAR REGULATORY COMMISSION

[!

1 o WASHINGTON, D.C. 20066-0001

% June 30, 1997 i

Mr. E. Thomas Boulette, Ph.D

Senior Vice Freuuent - nuclear i Boston Edison Company i Pilgrim Nuclear Power Station RFD #1 Rocky Hill Road l Plymouth, MA 02360

SUBJECT:

REQUEST TO CREDIT CONTAINMENT OVERPRESSURE TO SATISFY NET POSITIVE

} SUCTION HEAD (NPSH) REQUIREMENTS, AND SUBSEQUENT DEFERRAL OF REVIEW j REQUEST BASED ON 10 CFR 50.59 EVALUATION - PILGRIM NUCLEAR POWER

,' STATION (TAC NO. M97789) l

Dear Mr. Boulette:

l By letters dated January 20 and January 30, 1997, the Boston Edison Company

, (BECo/the licensee) submitted an amendment request for the Pilgrim Nuclear

. Power Station (PNPS). The licensee requested to update the Updated Final Safety Analysis Report (UFSAR) to credit containment overpressure to satisfy Emergency Core Cooling System (ECCS) pump NPSH requirements, and also requested approval of revised containment pressure and suppression pool

temperature analyses for an increased ultimate heat sink temperature of 75 'F,

! versus the current 65 'F. The NRC staff had determined that the licensee's l need for containment overpressure constituted an Unreviewed Safety Question

(USQ) and approval of the amendment request was needed to support plant

! startup.

4 The licensee subsequently determined that because of the reduced head losses I

associated with new ECCS suction strainers installed during the refueling i outage 11, credit for containment overpressure, assuming a 65 'F ultimate heat i sink temperature, is no longer necessary to satisfy low-pressure coolant injection and core spray pump NPSH requirements. By letter dated April 11, s 1997, the licensee submitted a 10 CFR 50.59 safety evaluation supporting this i conclusion and committed to enter a " loss of containment cooling" limiting l condition for operation when the ultimate heat sink temperature exceeds 65 'F. By letter dated June 20, 1997, BEco revised the above commitment by changing the administrative limit from 65 *F to 68 'F. BECo has performed 4 analysis using a 68 'F seawater temperature and determined that credit for

. containment overpressure is not needed at this temperature. While we have not been able to perform an in depth review of your June 20, 1997, submittal the

10 CFR 50.59 safety evaluation appears to be consistent with the plant's

licensing basis. We acknowledge that BEco has concluded that overpressure is not necessary to satisfy NPSH requirements at 68 *F or less and that the

. change of the administrative limit on service water temperature has been fi implemented.

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) 9707020360 970630 PDR ADOCK 05000293 NRC FRE CENTER COPY P PDR

l E. Thomas Boulette  !

If you have any questions in this matter, please contact Mr. Alan Wang at (301) 415-1445.

Sincerely, Original signed by Patrick D. Milano, Acting Director Project Directorate I-3 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation Docket No. 50-293 cc: See next page Distribution

' Docket File AWang CBerlinger PUBLIC OGC RConte, RI PDI-3 RF ACRS SVarga GCarpenter PMilano HDawson JKudrick DOCUMENT NAME: G:\ PILGRIM \NPSH.592 Ti ,eeehe e sepy of this dessement,indeace in the ben: "C" = Coqy without attachmentlenclosure *E* = Copy with attachment / enclosure *N* = No copy 0FFICE PM:PDI-3 LA:PDI-10 V] (A)D:PDInh , l l NAME AWang idV SLittl F PMilano U N DATE 06/r/97 06/M/97 06/ 3 0 /97 0FFICIAL RECORD COPY l

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,a b E. Thomas Boulette Pilgrim Nuclear Power Station cc:

Mr. Leon J. Olivier Mr. Jeffery Keene Vice President of Nuclear Licensing Division Manager  !

Operations & Station Director Boston Edison Company  !

Pilgrim Nuclear Power Station 600 Rocky Hill Road l IFD #1 Rocky Hill Road Plymouth, MA 02360-5599 Plymouth, MA 02360 Ms. Nancy Desmond Resident Inspector Manager, Reg. Affairs Dept.

U. S. Nuclear Regulatory Commission Pilgrim Nuclear Power Station  !

Pilgrim Nuclear Power Station RFD #1 Rocky Hill Road j Post Office Box 867 Plymouth, MA 02360  ;

Plymouth, MA 02360  :

Mr. David F. Tarantino I Chairman, Board of Selectmen Nuclear Information Manager l 11 Lincoln Street Pilgrim Nuclear Power Station l Plymouth, MA 02360 RFD #1, Rocky Hill Road Plymouth, MA 02360 Chairman, Duxbury Board of Selectmen l Town Hall Ms. Kathleen M. O'Toole 878 Tremont Street Secretary of Public Safety Duxbury, MA 02332 Executive Office of :ublic Safety One Ashburton Place Office of the Commissioner Boston, MA 02108 Massachusetts Department of Environmental Protection Mr. Peter LaPorte, Director One Winter Street Attn: James Muckerheide Boston, MA 02108 Massachusetts Emergency Management Agency l Office of the Attorney General 400 Worcester Road l One Ashburton Place P.O. Box 1496 20th Floor Framingham, MA 01701-0317 Boston, MA 02108

! Chairman, Citizens Urging Mr. Robert M. Hallisey, Director Responsible Energy i Radiation Control Program P.O. Box 2621 Massachusetts Department of Duxbury, MA 02331 Public Health  ;

305 South Street Citizens at Risk

Boston, MA 02130 P.O. Box 3803

l. Plymouth, MA 02361 Regional Administrator, Region I U. S. Nuclear Regulatory Commission W.S. Stowe, Esquire 475 Allendale Road Boston Edison Company King of Prussia, PA 19406 800 Boylston St., 36th Floor Boston, MA 02199 Ms. Jane Fleming

, 8 Oceanwood Drive i Duxbury, MA 0233  ;

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cc: (cont.)

1 Chairman Nuclear Matters Conunittee l Town Hall l

.11 Lincoln Street l Plymouth, MA 02360 j

Mr. William D. Meinert Nuclear Engineer Massachusetts Municipal Wholesale Electric Company P.O. Box 426 l Ludlow, MA 01056-0426 1

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