ML20141C000

Requests Addl Info on NRC Bulletin 96-003, Potential Plugging of ECC Suction Strainers by Debris in BWR, for Plant,Units 1 & 2

ML20141C000
Person / Time
Site:	Hatch
Issue date:	05/15/1997
From:	Jabbour K NRC (Affiliation Not Assigned)
To:	Sumner H SOUTHERN NUCLEAR OPERATING CO.
References
IEB-96-003, IEB-96-3, TAC-M96148, TAC-M96149, NUDOCS 9705160103
Download: ML20141C000 (4)

Text

._- . _ . _. _ _. _ _ _ __ __

1 May 15, 1997 i Mr. H. L. Sumner, Jr.

Vice President Southern Nuclear Operating Company, Inc.

P. O. Box 1295 Birmingham, Alabama 35201-1295

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION ON NRC BULLETIN 96-03 " POTENTIAL ,

PLUGGING OF EMERGENCY CORE COOLING SUCTION STRAINERS BY DEBRIS IN l BOILING-WATER REACTORS" - EDWIN I. HATCH NUCLEAR PLANT, UNITS 1 l

AND 2 (TAC NOS. M96148 AND M96149)

Dear Mr. Sumner:

By letters dated August 30 and October 1, 1996, and March 25, 1997, you l responded to NRC Bulletin 96-03 regarding the above subject. Based on our l

review, we find that additional information, in response to the comments  ;

outlined in the enclosure, is needed to enable the NRC staff to complete its  !

i review of your responses for Hatch Units 1 and 2. These comments were L

discussed with your staff via a telephone conference on May 13, 1997.

j Please provide the requested information as soon as'possible in order to allow sufficient time for the staff to review the requested information on a schedule compatible with your requested date. If you have any questions, i please contact me at (301) 415-1496. '

Sincerely, ORIGINAL SIGNED BY J. ZIMMERMAN FOR:

Kahtan N. Jabbour, Senior Project Manager Project Directorate II-2 l Division of Reactor Projects - I/II l Office of Nuclear Reactor Regulation Docket Nos. 50-321 and 50-366 l l l

Enclosure:

Request For Additional Information cc w/ encl: See next page l

l Distribution:

Docket File HBerkow OGC l PUBLIC LBerry ACRS PD II-2 Rdg. KJabbour JJohnson, RII 1 D

SVarga CBerlinger PSkinner, RII 1G0034 i F To receive a copy of this document, ind h% ir(.t x: "C" = copy without i

attachment /enslosure "E" = Copy with achment/enclosprijp"N"=Nocopy 0FFICE PM:PDhl/2 LA:PDII-(2A BC:SCSB: l SRJREM/ D:PDIP2 l NAME WXdABBdVR:cn LBE,RRY4\fk' CBERLINGER LPHILLIPS .J 11BER_KW DATEX f//// /97 6 / lL//97 (/ /if /97 f" / / 9 /9 f i / /# /97 '

/ /97 W.lMFN1 NAME:' G:\ HATCH \STRAINEA 0FFICIAL RECORD COPY l E P228a n g88aga1 NRC RLE CEHER COPY e -

pa rerg l g k UNITED STATES s* j 2

NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20066 J001

,/ May 15,1997 k .. ..

Mr. H. L. Sumner, Jr.

Vice President Southern Nuclear Operating Company, Inc.

P. O. Box 1295 Birmingham, Alabama 35201-1295 l

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION ON NRC BULLETIN 96-03 " POTENTIAL PLUGGING OF EMERGENCY CORE COOLING SUCTION STRAINERS BY DEBRIS IN BOILING-WATER REACTORS" - EDWIN I. HATCH NUCLEAR PLANT, UNITS 1 AND 2 (TAC NOS. M96148 AND M96149)

Dear Mr. Sumner:

By letters dated August 30 and October 1, 1996, and March 25, 1997, you responded to NRC Bulletin 96-03 regarding the above subject. Based on our review, we find that additional information, in response to the comments outlined in the enclosure, is needed to enable the NRC staff to complete its review of your responses for Hatch Units 1 and 2. These comments were discussed with your staff via a telephone conference on May 13, 1997.

Please provide the requested information as soon as possible in order to allow sufficient time for the staff to review the requested information on a l schedule compatible with your requested date. If you have any questions, please contact me at (301) 415-1496.

Sincerely, A

tan N. our, Senio Project Manager Project Directorate II-2 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation Docket Nos. 50-321 and 50-366

Enclosure:

Request For Additional Information '

cc w/ encl: See next page 1

1 Edwin I. Hatch Nuclear Plant l Units 1 and 2 i cc: .

Mr. Ernest L. Blake, Jr. Mr. Thomas P. Mozingo l Shaw, Pittman, Potts and Trowbridge Program Manager i 2300 N Street, NW. Nuclear Operations Washington, DC 20037 Oglethorpe Power Corporation 2100 East Exchange Place Mr. D. M. Crowe P. O. Box 1349 l Manager, Licensing Tucker, Georgia 30085-1349 i Southern Nuclear-Operating Company, Inc. Charles A. Patrizia, Esquire P. O. Box 1295 Paul, Hastings, Janofsky & Walker Birmingham, Alabama 35201-1295 loth Floor 1299 Pennsylvania Avenue Resident Inspector Washington, DC 20004-9500 U.S. Nuclear Regulatory Commission '

11030 Hatch Parkway North. Chairman Baxley, Georgia 31513 Appling County Commissioners County Courthouse Regional Administrator, Region II Baxley, Georgia 31513 U.S. Nuclear Regulatory Commission Atlanta Federal Center Mr. W. G. Harriston, III 61 Forsyth Street, S.W., Suite 23T85 President and Chief Executive )

Atlanta, Georgia 30303 Officer Southern Nuclear Operating Mr. Charles H. Badger Company, Inc. i Office of Planning and Budget P. O. Box 1295 I Room 610 ' Birmingham, Alabama 35201-1295 270 Washington Street, SW.

Atlanta, Georgia 30334 Mr. J. D. Woodard Executive Vice President Harold Reheis, Director Southern Nuclear Operating Department of Natural Resources Company, Inc.

205 Butler Street, SE., Suite 1252 P. O. Box 1295 Atlanta, Georgia 30334 Birmingham, Alabama 35201-1295 Steven M. Jackson Mr. P. W. Wells Senior Engineer - Power Supply General Manager, Edwin I. Hatch Municipal Electric Authority Nuclear Plant of Georgia Southern Nuclear Operating 1470 Riveredge Parkway, NW Company, Inc.

Atlanta, Georgia 30328-4684 11030 Hatch Parkway North Baxley, Georgia 31513 1

l l

_ __.__m . _ _ _ _ . _ _ _. _ . __ _ - _ __ _. _ .._. . . _ _ _ _ _ . __

REQUEST FOR ADDITIONAL INFORMATION ON NRC BULLETIN 96-03 " POTENTIAL PLUGGING OF EMERGENCY CORE  :

COOLING SUCTION STRAINERS BY DEBRIS IN BOILING-WATER REACTORS" DOCKET NOS. 50-321 AND 50-366 I

1. Your estimates of debris generated / transported do not include either I calcium silicate or urethane. Please provide your justification for not including them.

1

2. Have you conducted parametric evaluations to demonstrate that the head j loss is maximized for the selected break? Your March 25, 1997,  ;

submittal appears to focus entirely on maximizing the quantity of i fibrous insulation.  !

l

3. Please describe the transportable materials, and discuss how they were incorporated into the head loss estimate?

4. Please discuss whether or not you intend to have a dedicated strainer-for each pump such that one residual' heat removal strainer and two core spray strainers can handle 100 percent of all debris generated /

transported? If not, do' you intend to use a common header? Please provide sufficient details of your design.

I

5. Using the generic methodology provided in the_ General Electric report as applied to Hatch, describe the characteristics, including the sizes, of the strainers proposed for use at Hatch. What is the actual size of the strainer used in the GE testing? In particular, please provide details regarding the crevices (troughs), etc.

6. What is the fraction of the insulation contained below the grating in l the " worst-case" break?

7. During a call with the licensee on May 13, 1997, the licensee stated that it will maintain the margin with regards to minimum containment l pressure available and low-pressure coolant injection (LPCI) net l positive suction head required. This is described in the Hatch Unit 1 i Final Safety Analysis Report (FSAR) on page 14.4-15. However, this  !

statement is not consistent to the statements with regard to the'use of i containment overpressure on page E-2 of the March 25, 1997, submittal.

In particular, the staff's licensing safety evaluation and the FSAR for l Hatch, Unit 1, indicate that credit was taken for 1 psig of containment i overpressure for the LPCI pumps, and that no overpressure was taken for i the core spray pumps. Please reconcile the docketed information with the information provided in the phone conference.

Enclosure l

, -