ML20214C416
| ML20214C416 | |
| Person / Time | |
|---|---|
| Site: | Fort Saint Vrain  |
| Issue date: | 11/17/1986 |
| From: | Robert Williams PUBLIC SERVICE CO. OF COLORADO |
| To: | Gagliardo J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| IEB-86-003, IEB-86-3, P-86625, NUDOCS 8611210094 | |
| Download: ML20214C416 (4) | |
Text
,
O Public Service ~
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P.o. Box 840 Denver, Co 80201-0840 November 17, 1986 R.O. WILLIAMS, JR.
EN Fort St. Vrain QPR,E$
R P TIONS Unit No. 1 P-86625 Regional Administrator Region IV U. S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76011 Attention: Mr. J. E. Gagliardo, Chief Reactor Projects Branch Docket No. 50-267
SUBJECT:
Response to IE Bulletin 86-03
REFERENCE:
IE Bulletin 86-03, dated October 8, 1986 (G-86539)
Dear Mr. Gagliardo:
This letter provides PSC's response to IE Bulletin 86-03, Potential Failure of Multiple ECCS Pumps due to Single Failure of Air-0perated Valve in Minimum Flow Recirculation Line, as applicable to Fort St.
Vrain. The individual actions required by IE Bulletin 86-03 have been addressed below.
- 1) ACTION REQUIRED:
Promptly det:emine whether or not your facility has a single failure vulnerability in the minimum flow recirculation line of any ECCS pump that could cause a failure of more than one ECCS train.
PSC RESPONSE:
The Fort St.
Vrain HTGR does not have systems that have been designated as ECCS.
For the purposes of this Bulletin, we have reviewed the FSV systems that can perform reactor core cooling functions. These systems may be used to assure forced cooling during normal shutdown, backup shutdown, or safe shutdown cooling.
Pumps which provide cooling water flow through the PCRV liner cooling tubes were also reviewed.
For these functions, PSC has performed evaluations for single failure vulnerability in minimum flow recirculation lines of pumps in the feedwater, condensate, reactor plant cooling water, firewater, circulating water make-up, and service water systems. The results of these investigations are as follows:
8611210094 861117
'N PDR ADOCK 05000267 G
PDR I o
t P-86625 Page 2 November 17, 1986 A.
Boiler Feed Pumps (3) - The three boiler feed pumps each have separate recirculation lines that do include air operated isolation valves.
These isolation valves fail open.
Any single failure would not preclude proper operation of the redundant pump (s).
B.
Condensate Pumps (4) - These pumps do not have or require recirculation capability and therefore, single failure vulnerability in a minimum flow recirculation line does not exist.
C.
Reactor Plant Cooling Water System Pumps (4) - The Reactor Plant Cooling Water System is a closed loop, two-train system with two 100% capacity pumps (one standby) per train, which precludes single failure vulnerability. Additionally, these pumps do not have or require minimum flow recirculation lines.
D.
Emergency Water Booster Pumps (2) - These pumps do not have or require recirculation capability and therefore, single failure vulnerability in a minimum flow recirculation line does not exist.
E.
Firewater Pumps (2)
- These pumps do not have or require recirculation capability and therefore single failure vulnerability in a minimum flow recirculation line does not exist.
F.
Circulating Water Make-Up Pumps (2) - These pumps do not have minimum flow recirculation lines.
- However, from the common discharge line of the pumps that normally provide make-up to the main cooling tower, there is a
16"
" recirculation" line, manually valved, that provides a redundant means of filling the circulating water tower basin by gravity feed. Since the function of this line does not serve to protect the pumps and is manually valved into operation, a single failure in this line would not disable the pumps.
G.
Service Water Pumps (3) - These pumps do not have or require recirculation capability and therefore, single failure vulnerability in a minimum flow recirculation line does not exist.
- 2) ACTION REQUIRED:
If the problem exists:
(a) promptly instruct all operating shifts of the problem and measures to recognize and mitigate the problem; (b) promptly develop and implement corrective actions which bring your facility into compliance with GDC 35.
\\
P-86625 Paga 3 November 17, 1986 PSC RESPONSE:
As described in the response to (1) above, the failures reported in IE Bulletin 86-03 do not represent a problem at Fort St.
Vrain.
- 3) ACTION REQUIRED:
Within 30 days of receipt of this bulletin, (a) provide a written report to the NRC which identifies whether or not this problem exists at your facility, (b) if the problem exists (or existed),
include in the report the justification for continued operation i
and identify the short-term modifications to plant operating procedures or hardware that have been or are being implemented to ensure safe plant operations.
PSC RESPONSE:
This letter is provided as the 30-day written report and, as previously evaluated in response to Action (1) above, the subject i
of IE Bulletin 86-03 does not represent a problem at Fort St.
Vrain, nor has it in the past for a minimum flow recirculation line.
- 4) ACTION REQUIRED:
If the problem exists (or existed), provide a written report within 90 days of receipt of this bulletin informing the NRC of the schedule for long-term resolution of this and/or any other significant problems that are identified as a result of this bulletin.
PSC RESPONSE:
As previously analyzed in Action (1) above, potential failure of multiple ECCS pumps due to single failure of an air-operated valve in a minimum flow recirculation line does not represent a i
problem at Fort St. Vrain. Therefore, this 30-day report is the only correspondence provided in accordance with the required action of IE Bulletin 86-03. No 90-day report will be submitted.
If you have any questions concerning this response, please contact M.
H. Holmes at (303) 480-6960.
Very truly yours, s
R. O. Williams, Jr., Vice President Nuclear Operations R0W/WMD:jmt cc:
U. S. Nuclear Regulatory Commission 4
l Document Control Desk Washington, D.C. 20555 i
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UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION In the Matter
)
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Public Service Company of Colorado
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Docket No. 50-267 Fort St. Vrain Unit No. 1
)
AFFIDAVIT R.
O.
- Williams, Jr., being first duly sworn, deposes and says:
That he is Vice President, Nuclear Operations, of Public Service Company of Colorado, the Licensee herein, that he has read the foregoing information and knows the contents thereof, and that the statements and matters set forth therein are true and correct to the best of his knowledge, information and belief.
s s
R. O. Williams, Jr.'
Vice President Nuclear Operations STATE OF d/y,a fhv
)
)
i COUNTY OF,6eatfuu
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i Subscribed and sworn to before me, a Notary Public on this 19 'E" day of Y)n u n?/u ;/
, 1986.
I (n}'h nup S, 0!!< //b !</W-sW Notary Public e<
My commission expires O/ / <7 /r 2 /~ '1')
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