ML20117M773

Forwards Requested Info to Support Review of Proposed TS Change TS 3.7.5,raising Minimum Water Level of Standby Nuclear SW Pond from 570 Feet to 571 Feet

ML20117M773
Person / Time
Site:	Catawba
Issue date:	09/10/1996
From:	Mccollum W DUKE POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20117M776	List: ML20117M773 ML20117M782 ML20117M791 ML20117M802
References
TAC-M94192, TAC-M94193, TAC-M95256, TAC-M95257, NUDOCS 9609180088
Download: ML20117M773 (5)

Text

f l ll l

^

Dbit>wer VI 'rry Wa.urtR. AkCxun JR.

duWebaNuEw. .neration Department ' Uce1%sident 4800 ConcordRoad N-(803)33b3300 office York, SC2976  ! (82)33b3D6Far l

,2 DUKE.*OWER September 10, 1996 l

! U.S. Nuclear Regulatory Commission-l Attention: Document Control Desk Washington, D.C. 20555 ,

j.  :

l

Subject:

Catawba Nuclear' Station, Units 1 and 2 ,

Docket Nos. 50-413 and 50-414 Proposed Technical Specification Change TS 3.7.5 Standby Nuclear Service Water Pond Supplemental Information (TAC M94192'and M94193) cM M 7f2f( , Al R2G r By letter dated Ncvember 15, 1995, Duke Power Company

! submitted a proposed Technical Specification change to TS '

l 3.7.5 to raise the minimum water level-'of the' standby nuclear service water pond (SNSWP) from 570 feet to 571  ;

l. feet.-

i l On August 21, 1996, a conference call took place between j l

Duke Power Company and NRC personnel. During that call  ;

j several additional pieces of information were requested in ,

l , support of review of'this amendment-' request. Enclosed are l four. attachments that supply the requested information. Due to the volume of material in the attachments,~a limited number of copies with attachments are provided.-

! If there are any questions regarding this information,

.please contact M.S.'Kitlan, Jr. at (803)/831-3205. J j

j Very truly yours,  :

l fff . jv b William R. McCollum, Jr. \j Attachments' l

5$N13 - C!f

.s. .

PDR ,

l

- .. I

Ik Document Control Desk Page 2 September 10, 1996 xc (w/o attachments):

S.D. Ebneter, Regional Administrator, Region II US Nuclear Regulatory Commission 101 Marietta Street, NW, Suite 2900 Atlanta, GA 30323 R.J. Freudenberger, Senior Resident Inspector Catawba Nuclear Station xc (with attachments)

P.S. Tam Senior Project Manager, ONRR 1

i M-i DUKE POWER COMPANY

[ CATAWBA NUCLEAR STATION t-

' Standby Nuclear Service Water Pond (SNSWP), Summary of Attached Information Attachments:

' l. . Standby Nuclear Service Water Pond - Thermal Analysis During One Unit LOCA and

' One Unit Shutdown, CNC-1150.01-00-0001, Rev 6.

i Revision 6 incorporates the effects ofincreasing the SNSWP minimum elevation from 570' MSL to 571' MSL, and the effects of changes to the area-volume curve,-

,[ heat loads, flow rates, and worst case meteorology. The SNSWP volume used as

an input to the thermal analysis takes into account inventory loss due to fuel pool

[ and auxiliary feedwater makeup. Changes to the heat loads on the SNSWP

included the addition of pump work. The uneven " flow split" between the short and long discharge flowpaths to the SNSWP has also been evaluated.

i

2. Catawba Standby Nuclear Service Water Pond Physical Testing During February j 1995., R.E. Baker.

L 2

Stratification and Dye testing was conducted on the SNSWP during a one-unit 4-planned shut down while the Nuclear Service water system supply and return were j aligned to the SNSWP. The testing was designed to verify the existence of

' l stratification in the SNSWP, verify that the heated surface layer spreads out over J

, the SNSWP, verify the heated layer is not withdrawn at the intake, and verify the l flow is not short-circuiting between the short-arm discharge and the intake. l 1

3. Catawba Nuclear Station, Standby Nuclear Service Water Pond Analysis, July 1995, Dr. B. L. Sill. l l

This is an assessment of the adequacy of the SNSWP thermal analysis computer j model (attachment 1), based on actual SNSWP test data (attachment 2) and a critique of the computer model and the calculations used in the computer model.

Report concludes computer model is adequate and physical testing confirms pond performed as predicted. Report did recommend enhancing the model by including i some initial mixing of the discharge. The incorporation of this enhancement is in I progress and should complete Fall of '96. '

4. Meteorological Data for Catawba Nuclear Station vs Charlotte Airport, Summer 1995.

Hourly meteorological data consisting of CNS dry bulb (T) and dew point (Td) and Charlotte Airport dry bulb (T) and dew point (Tdew) temperature for the .

I Summer of 1995 (June 30 through Sept 1).

l DUKE POWER COMPANY

! CATAWBA NUCLEAR STATION Standby Nuclear Service Water Pond (SNSWP), Summary of Attached Information l ' Attachments:

e r 1. Standby Nuclear Service Water Pond - Thermal Analysis During One Unit LOCA and j One Unit Shutdown, CNC-1150.01-00-0001, Rev 6.

' Revision 6 incorporates the effects ofincreasing the SNSWP minimum elevation

- from 570' MSL to 571' MSL, and the effects of changes to the area-volume curve, l heat loads, flow rates, and worst case meteorology. The SNSWP volume used as '

- an input to the thermal analysis takes into account inventory loss due to fuel pool and auxiliary feedwater makeup. Changes to the heat loads on the SNSWP -

. included the addition of pump work. The uneven " flow split" between the short

, and long discharge flowpaths to the SNSWP has also been evaluated.

2. Catawba Standby Nuclear Service Water Pond Physical Testing During February i 1995., R.E. Baker.

Stratification and Dye testing was conducted on the SNSWP during a one-unit planned shut down while the Nuclear Service water system supply and return were aligned to the SNSWP. The testing was designed to verify the existence of stratification in the SNSWP, verify that the heated surface layer spreads out over the SNSWP, verify the heated layer is not withdrawn at the intake, and verify the flo,w is not short-circuiting between the short-arm discharge and the intake.

3. Catawba Nuclear Station, Standby Nuclear Service Water Pond Analysis,' July 1995, I Dr. B. L. Sill.

This is an assessment of the adequacy of the SNSWP thermal analysis computer model (attachment 1), based on actual SNSWP test data (attachment 2) and a critique of the computer model and the calculations used in the computer model.

Report concludes computer model is adequate and physical testing confirms pond  !

performed as predicted. Report did recommend enhancing the model by including some initial mixing of the discharge. The incorporation of this enhancement is in progress and should complete Fall of '%.

4. Meteorological Data for Catawba Nuclear Station vs Charlotte Airport, Summer 1995.

Hourly meteorological data consisting of CNS dry bulb (T) and dew point (Td) and Charlotte Airport dry bulb (T) and dew point (Tdew) temperature for the Summer of 1995 (June 30 through Sept 1).

4 4

+ . , . .

l 1

ATTACHMENT 1 l l

1 l

l 1

l l

l l

i l

1 l

l l

l