ML20050B117
| ML20050B117 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 03/26/1982 |
| From: | Nichols T SOUTH CAROLINA ELECTRIC & GAS CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8204050017 | |
| Download: ML20050B117 (2) | |
Text
.
N SOUTH CAROLINA ELECTRIC a GAS COMPANY O
(b
,o u o,,.c
.o 7..
p CotunsiA, Souin CAnoLINA 29218 g
T C.Nicnots.Jn ves P.asesme a.o Geov. Esscun<t k"
March 26, 1982 R 021982M y
=
R NOW ri g m gagegg Mr. Harold R. Denton, Director g
M*n awsfun u TDC
/f Office of Nuclear Reactor Regulation g
U. S. Nuclear Regulatory Carmission Washington, D.C.
20555
Subject:
Virgil C. Sumter Nuclear Station Docket No. 50/395 Modified Response to FSAR Question 211.39
Dear Mr. Denton:
South Carolina Electric and Gas Ccmpany (SCE&G) herein provides an update to the FSAR discussion regardirg actions taken by the operator that would effect a IOCA during the time accumulator isolation valves are closed with power locked out.
This revision is shown on the attached FSAR page 211.39, Iten 2, and will be incorporated into the next anendment to the FSAR.
The change to the FSAR is consistant with current Technical Specification 3.5.3 and is still consistant with the analysis requested by Question 211.39.
If you have any questions, please let us know.
Very truly yours,
-k e
g T. C. Nichols, Jr.
RBC:'IG:lkb Attachttent cc:
V. C. Sumter (w/o attach.)
O. S. Bradham G. H. Fischer (w/o attach.)
A. R. Koon H. N. Cyrus M. N. Browne T. C. Nichols, Jr.
(w/o attach.)
G. J. Braddick M. B. Whitaker, Jr.
J. C. Ruoff J. P. O'Reilly J. L. Skolds H. T. Babb J. B. Knotts, Jr.
D. A. Nauman B. A. Bursey C. L. Ligon (NSRC)
NPCF W. A. Willians, Jr.
File R. B. Clary
[
8204050017 020326 SI l PDR ADOCK 05000395 PDR
211.N Assess the potential for, and consequences of, a LOCA
{
during the time the accumulator injection tanks are iso-lated with power locked out to valve operators.- (That is, during shutdown and startup operations.)
~
RESPONSE
During the shutdown the following operator actions pertain to the isola-tion of ECCS equipment and would effect a LOCA during the time accumula-tor isolation valves are closed with power locked out.
(Startup is not addressed since shutdown is more limiting due to the higher core decay heat generation):
1.
At 1900 poig the operator is instructed to manually block the auto-matic safety injection signal. This action disarms the safety in-jection signals from the pressurizer pressure transmitter along with the steam flow transmitters.
All other safety injection signals including containment high pressure and high steam line dif-ferential pressure are armed and will actuate safety injection if their setpoints are exceeded. Manual safety injection actuation is also available.
9 2.
At 1000 psig, the operator closes and locks out the safet injection At 00 Fs a-jl bv o n e.
-.; high 31 accumulator isola tion valves.4 also locks out __.
head charging pump.
At this time, two residual heat removal pumps
.(low head safety injection) would be available from either automatic or manual safety injection actuation.
3.
At less than 425 psig and 3500F, the operator aligns RHRS suction to the RCS. The valves in the line from the refueling water storage tank (RWST) are closed.
The significance of these actions on the mitigation of a LOCA when power is locked out to the isolation valves is that:
(
SI 211.39-1 AMENDMENT #
- c. = =,
A P Cl L, I'l T 2.
L
_ _ _ _ _ _ _ _