ML20054K568
| ML20054K568 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 06/28/1982 |
| From: | Dixon O SOUTH CAROLINA ELECTRIC & GAS CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0588, RTR-NUREG-588 NUDOCS 8207020332 | |
| Download: ML20054K568 (2) | |
Text
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SOUTH CAROLINA Electric & GAS COMPANY eoer carece som v..
Cocuus A. SouvM CAROuNA 29218 O. W. DI AON, JM.
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June 28, 1982 o
Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Connission Washington, D.C.
20555
Subject:
Virgil C. Stener Nuclear Station Docket No. 50/395 NURH3 0588 Report Question
Dear Mr. Denton:
South Carolina Electric and Gas Coupany hereby provides a response to a question from the NRC staff concerning safety classification of the letdown line in the Chenical Volume and Control System (CVCS) as discussed in Revision 4 of our NUREG 0588 Report (see Attachment).
If you have additional questions, please let us know.
Very truly yours,
/
- o. W.
- ixon, NEC:OWD,jr:lkb Attachment cc:
V. C. Sumter (w/o attach.)
G. H. Fischer (w/o attach.)
H. N. Cyrus T. C. Nichols, Jr.
(w/o attach.)
M. B. Whitaker, Jr.
J. P. O'Reilly H. T. Babb D. A. Nauman l
C. L. Ligon (NSRC)
(
W. A. Williams, Jr.
R. B. Clary
- o. S. Bradham A. R. Koon l
M. N. Browne G. J. Braddick J. L. Skolds J. B. Knotts, Jr.
B. A. Bursey NPCF I
File
@207020332 820628
~~
PDR ADOCK 05000395 A
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ATPACHMENP Question:
The staff requested that the applicant provide justification why the letdown portion of the Chenical and Volume Control System (listed in Appendix D) is not considered safety-related. The applicant should review the applicability of Information Notice No. 79-22 and address the conpleteness of the safety-system lists with the above exenption.
Response
The letdown portion is considered as safety-related with respect to ASME Code requirements for the piping.
It is assumed that the NRC staff is referring to Class lE equignent designations. The letdom portion of the chemical and volune control system is required for only one (No. 2) of the following safety-related functions.
- 1) Emergency Reactor Shutdown
- 2) Containment Isolation
- 3) Reactor Core Cooling
- 4) Containment Heat Renoval
- 5) Core Residual Heat Removal
- 6) Prevention of Significant Release of Radioactive Material to the Environment As indicated, the letdown portion is only required to perform a containment isolation function for accident mitigation. The containment isolation valves are therfore considered safety-related and are designated as Class lE.
The following valves are involved.
8149 A, B, C (Inside Containment) 8152 (Outside Containment)
These valves were reviewed and qualified under the NUREG 0588 Review.
This is documented in Rev. 4 to the Virgil C. Suntner NLREG 0588 submittal dated February 19, 1982.
SCE&G subnitted the evaluation of Information Notice (IEN) 79-22 to the NRC on February 26, 1982. This submittal addressed both environmental interaction and control system failures.
In synopsis, the evaluation determined that Chapter 15 of the FSAR adequately bounded the consequences of such failures. SCE&G does not consider it necessary to re-evaluate the classification of the letdown system components based upon the above information. Therefore, the safety-system lists are considered to be conplete and accurate.
_e.
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