ML20134D358

Responds to SER Confirmatory Item 47 Re Boron Dilution. Figure 2.2.1, Charging,Letdown & Seal Water, Referenced in ,Encl

ML20134D358
Person / Time
Site:	Vogtle
Issue date:	08/12/1985
From:	Bailey J GEORGIA POWER CO.
To:	Adensam E, Denton Office of Nuclear Reactor Regulation
References
0053V, 53V, GN-676, NUDOCS 8508190193
Download: ML20134D358 (2)

Text

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= ' Georgia Power Compar*y Routa 2, Box 299A

. Waynesboro, Georgia 30830

. Telephone 404 554 9961 404 724 8114 Southern Company Services, Inc.

Post Office Box 2625 Birmingham. Alabama 35202 Telephone 205 8704011 Vogtle Proj,ect August 12, 1985 Director of Nuclear Reactor Regulation File: X7BC35 Attention: Ms. Elinor G. Adensam, Chief Log: GN-676 Licensing Branch #4 Division of Licensing U.S. Nuclear Regulatory Commission Washington, D.C. 20555 REF: Bailey to Denton, GN-656, Dated 7/25/85 NRC DOCKET NUMBERS 50-424 AND 50-425 CONSTRUCTION PERMIT NUMBERS CPPR-108 AND CPPR-1209 V0GTLE ELECTRIC GENERATING PLANT - UNITS 1 AND 2 SER CONFIRMATORY ITEM-47: BORON DILUTION

Dear Mr. Denton:

The attachment to the referenced letter referred to " Figures 2-1 through 2-6;"

the figures were not in the attachment. The P&ID figures describing the CVCS system are found in FSAR Figure 9.3.4-1 sheets 1 through 6. Attached is a correction to the page of the referenced attachment.

P If your staff requires any additional information, please do not hesitate to ,

contact me.

Sincerely, pJ.A..4 Bailey '

Project Licensing Manager JAB /caa Attachment .-

xc: D. O. Foster G. Bockhold, Jr R. A. Thomas T. Johnson (W/o Att.)

J. E. Joiner, Esquire D. C. Teper (W/o Att.)

B. W. Churchill, Esquire L. Fowler M. A. Miller W. C. Ramsey B. Jones, Esquire (W/o Att.) Vogtle Project File L. T. Gucwa 0053V r i NR E

D f \g

N 2.2 GENERAL DESCRIPTION FSAR Figure 9.3.4-1 Sheets 1 through 6 shows the CVCS piping and instrumentation.

2.2.1 CHARGING, LETDOWN AND SEAL WATER The charging and letdown functions of the system are employed to maintain a prograsped water level in the reactor coplant system pressurizer, thus maintaining proper reactor coolant inventory during all phases of plant operation. This is achieved by means of a continuou's feed and bleed process during which time the feed rate is automatically controlled by pressurizer water level. The bleed rate can be chosen to suit various plant operational requirements by selecting the proper combination of letdown orifices in the letdown flow path. Reactor coolant is discharged to the CVCS from cold leg of the RCS; it then flows through the shell side of the regenerative heat exchanger where, during normal operation, its temperature is reduced to approximately 290*F. The coolant then experiences a large pressure reduction in passing through a letdown orifice (A, = 1700 psi) and after passing through the containment boundary it flows through the tube side of the letdown heat exchanger where its temperature is further reduced to about 115*F.

Downstream of the letdown heat exchanger a second pressure reduction occurs as the coolant flows to the purification system demineralizers. This pressure reduction is performed by the low-pressure letdown valve, which maintains an upstream pressure sufficient to prevent flashing downstream of the letdnwn orifices.

The coolant then normally flows through one of the mixed-bed demineralizers through the reactor coolant filter, and into the volume control tank via a diversion valve and finally a spray nozzle in the gas space of the tank. The gas space in the volume control tank is filled with hydrogen, which is regulated to a pressure of 15-20 psig during normal plant operation. The partial pressure of hydrogen in the volume control tank determines the concentration of hydrogen dissolved in the reactor coolant.

80260: 10/022285 3

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